diff options
Diffstat (limited to 'ext/json')
| -rw-r--r-- | ext/json/LICENSE.MIT | 17 | ||||
| -rw-r--r-- | ext/json/README.md | 566 | ||||
| -rw-r--r-- | ext/json/json.hpp | 15313 |
3 files changed, 10531 insertions, 5365 deletions
diff --git a/ext/json/LICENSE.MIT b/ext/json/LICENSE.MIT index e2ac4891..00599afe 100644 --- a/ext/json/LICENSE.MIT +++ b/ext/json/LICENSE.MIT @@ -1,14 +1,13 @@ -The library is licensed under the MIT License -<http://opensource.org/licenses/MIT>: +MIT License -Copyright (c) 2013-2016 Niels Lohmann +Copyright (c) 2013-2017 Niels Lohmann -Permission is hereby granted, free of charge, to any person obtaining a copy of -this software and associated documentation files (the "Software"), to deal in -the Software without restriction, including without limitation the rights to -use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies -of the Software, and to permit persons to whom the Software is furnished to do -so, subject to the following conditions: +Permission is hereby granted, free of charge, to any person obtaining a copy +of this software and associated documentation files (the "Software"), to deal +in the Software without restriction, including without limitation the rights +to use, copy, modify, merge, publish, distribute, sublicense, and/or sell +copies of the Software, and to permit persons to whom the Software is +furnished to do so, subject to the following conditions: The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software. diff --git a/ext/json/README.md b/ext/json/README.md index cb05d744..256409e3 100644 --- a/ext/json/README.md +++ b/ext/json/README.md @@ -1,30 +1,53 @@ - +[](https://github.com/nlohmann/json/releases) [](https://travis-ci.org/nlohmann/json) -[](https://ci.appveyor.com/project/nlohmann/json) +[](https://ci.appveyor.com/project/nlohmann/json) [](https://coveralls.io/r/nlohmann/json) [](https://scan.coverity.com/projects/nlohmann-json) -[](http://melpon.org/wandbox/permlink/wuiuqYiYqRTdI3rG) +[](https://www.codacy.com/app/nlohmann/json?utm_source=github.com&utm_medium=referral&utm_content=nlohmann/json&utm_campaign=Badge_Grade) +[](https://wandbox.org/permlink/Op57X0V7fTf2tdwl) [](http://nlohmann.github.io/json) [](https://raw.githubusercontent.com/nlohmann/json/master/LICENSE.MIT) [](https://github.com/nlohmann/json/releases) [](http://github.com/nlohmann/json/issues) +[](http://isitmaintained.com/project/nlohmann/json "Average time to resolve an issue") +[](https://bestpractices.coreinfrastructure.org/projects/289) + +- [Design goals](#design-goals) +- [Integration](#integration) +- [Examples](#examples) + - [JSON as first-class data type](#json-as-first-class-data-type) + - [Serialization / Deserialization](#serialization--deserialization) + - [STL-like access](#stl-like-access) + - [Conversion from STL containers](#conversion-from-stl-containers) + - [JSON Pointer and JSON Patch](#json-pointer-and-json-patch) + - [Implicit conversions](#implicit-conversions) + - [Conversions to/from arbitrary types](#arbitrary-types-conversions) + - [Binary formats (CBOR and MessagePack)](#binary-formats-cbor-and-messagepack) +- [Supported compilers](#supported-compilers) +- [License](#license) +- [Contact](#contact) +- [Thanks](#thanks) +- [Used third-party tools](#used-third-party-tools) +- [Projects using JSON for Modern C++](#projects-using-json-for-modern-c) +- [Notes](#notes) +- [Execute unit tests](#execute-unit-tests) ## Design goals There are myriads of [JSON](http://json.org) libraries out there, and each may even have its reason to exist. Our class had these design goals: -- **Intuitive syntax**. In languages such as Python, JSON feels like a first class data type. We used all the operator magic of modern C++ to achieve the same feeling in your code. Check out the [examples below](#examples) and you know, what I mean. +- **Intuitive syntax**. In languages such as Python, JSON feels like a first class data type. We used all the operator magic of modern C++ to achieve the same feeling in your code. Check out the [examples below](#examples) and you'll know what I mean. - **Trivial integration**. Our whole code consists of a single header file [`json.hpp`](https://github.com/nlohmann/json/blob/develop/src/json.hpp). That's it. No library, no subproject, no dependencies, no complex build system. The class is written in vanilla C++11. All in all, everything should require no adjustment of your compiler flags or project settings. -- **Serious testing**. Our class is heavily [unit-tested](https://github.com/nlohmann/json/blob/master/test/src/unit.cpp) and covers [100%](https://coveralls.io/r/nlohmann/json) of the code, including all exceptional behavior. Furthermore, we checked with [Valgrind](http://valgrind.org) that there are no memory leaks. +- **Serious testing**. Our class is heavily [unit-tested](https://github.com/nlohmann/json/blob/master/test/src/unit.cpp) and covers [100%](https://coveralls.io/r/nlohmann/json) of the code, including all exceptional behavior. Furthermore, we checked with [Valgrind](http://valgrind.org) that there are no memory leaks. To maintain high quality, the project is following the [Core Infrastructure Initiative (CII) best practices](https://bestpractices.coreinfrastructure.org/projects/289). Other aspects were not so important to us: - **Memory efficiency**. Each JSON object has an overhead of one pointer (the maximal size of a union) and one enumeration element (1 byte). The default generalization uses the following C++ data types: `std::string` for strings, `int64_t`, `uint64_t` or `double` for numbers, `std::map` for objects, `std::vector` for arrays, and `bool` for Booleans. However, you can template the generalized class `basic_json` to your needs. -- **Speed**. We currently implement the parser as naive [recursive descent parser](http://en.wikipedia.org/wiki/Recursive_descent_parser) with hand coded string handling. It is fast enough, but a [LALR-parser](http://en.wikipedia.org/wiki/LALR_parser) with a decent regular expression processor should be even faster (but would consist of more files which makes the integration harder). +- **Speed**. There are certainly [faster JSON libraries](https://github.com/miloyip/nativejson-benchmark#parsing-time) out there. However, if your goal is to speed up your development by adding JSON support with a single header, then this library is the way to go. If you know how to use a `std::vector` or `std::map`, you are already set. See the [contribution guidelines](https://github.com/nlohmann/json/blob/master/.github/CONTRIBUTING.md#please-dont) for more information. @@ -44,9 +67,21 @@ to the files you want to use JSON objects. That's it. Do not forget to set the n :beer: If you are using OS X and [Homebrew](http://brew.sh), just type `brew tap nlohmann/json` and `brew install nlohmann_json` and you're set. If you want the bleeding edge rather than the latest release, use `brew install nlohmann_json --HEAD`. +If you are using the [Meson Build System](http://mesonbuild.com), then you can wrap this repo as a subproject. + +If you are using [Conan](https://www.conan.io/) to manage your dependencies, merely add `jsonformoderncpp/x.y.z@vthiery/stable` to your `conanfile.py`'s requires, where `x.y.z` is the release version you want to use. Please file issues [here](https://github.com/vthiery/conan-jsonformoderncpp/issues) if you experience problems with the packages. + +If you are using [hunter](https://github.com/ruslo/hunter/) on your project for external dependencies, then you can use the [nlohmann_json package](https://docs.hunter.sh/en/latest/packages/pkg/nlohmann_json.html). Please see the hunter project for any issues regarding the packaging. + +If you are using [vcpkg](https://github.com/Microsoft/vcpkg/) on your project for external dependencies, then you can use the [nlohmann-json package](https://github.com/Microsoft/vcpkg/tree/master/ports/nlohmann-json). Please see the vcpkg project for any issues regarding the packaging. + ## Examples +Beside the examples below, you may want to check the [documentation](https://nlohmann.github.io/json/) where each function contains a separate code example (e.g., check out [`emplace()`](https://nlohmann.github.io/json/classnlohmann_1_1basic__json_a602f275f0359ab181221384989810604.html#a602f275f0359ab181221384989810604)). All [example files](https://github.com/nlohmann/json/tree/develop/doc/examples) can be compiled and executed on their own (e.g., file [emplace.cpp](https://github.com/nlohmann/json/blob/develop/doc/examples/emplace.cpp)). + +### JSON as first-class data type + Here are some examples to give you an idea how to use the class. Assume you want to create the JSON object @@ -123,12 +158,14 @@ json empty_object_implicit = json({}); json empty_object_explicit = json::object(); // a way to express an _array_ of key/value pairs [["currency", "USD"], ["value", 42.99]] -json array_not_object = { json::array({"currency", "USD"}), json::array({"value", 42.99}) }; +json array_not_object = json::array({ {"currency", "USD"}, {"value", 42.99} }); ``` ### Serialization / Deserialization +#### To/from strings + You can create an object (deserialization) by appending `_json` to a string literal: ```cpp @@ -142,8 +179,14 @@ auto j2 = R"( "pi": 3.141 } )"_json; +``` + +Note that without appending the `_json` suffix, the passed string literal is not parsed, but just used as JSON string value. That is, `json j = "{ \"happy\": true, \"pi\": 3.141 }"` would just store the string `"{ "happy": true, "pi": 3.141 }"` rather than parsing the actual object. -// or explicitly +The above example can also be expressed explicitly using `json::parse()`: + +```cpp +// parse explicitly auto j3 = json::parse("{ \"happy\": true, \"pi\": 3.141 }"); ``` @@ -162,6 +205,31 @@ std::cout << j.dump(4) << std::endl; // } ``` +Note the difference between serialization and assignment: + +```cpp +// store a string in a JSON value +json j_string = "this is a string"; + +// retrieve the string value (implicit JSON to std::string conversion) +std::string cpp_string = j_string; +// retrieve the string value (explicit JSON to std::string conversion) +auto cpp_string2 = j_string.get<std::string>(); + +// retrieve the serialized value (explicit JSON serialization) +std::string serialized_string = j_string.dump(); + +// output of original string +std::cout << cpp_string << " == " << cpp_string2 << " == " << j_string.get<std::string>() << '\n'; +// output of serialized value +std::cout << j_string << " == " << serialized_string << std::endl; +``` + +`.dump()` always returns the serialized value, and `.get<std::string>()` returns the originally stored string value. + + +#### To/from streams (e.g. files, string streams) + You can also use streams to serialize and deserialize: ```cpp @@ -176,10 +244,37 @@ std::cout << j; std::cout << std::setw(4) << j << std::endl; ``` -These operators work for any subclasses of `std::istream` or `std::ostream`. +These operators work for any subclasses of `std::istream` or `std::ostream`. Here is the same example with files: + +```cpp +// read a JSON file +std::ifstream i("file.json"); +json j; +i >> j; + +// write prettified JSON to another file +std::ofstream o("pretty.json"); +o << std::setw(4) << j << std::endl; +``` Please note that setting the exception bit for `failbit` is inappropriate for this use case. It will result in program termination due to the `noexcept` specifier in use. +#### Read from iterator range + +You can also read JSON from an iterator range; that is, from any container accessible by iterators whose content is stored as contiguous byte sequence, for instance a `std::vector<std::uint8_t>`: + +```cpp +std::vector<std::uint8_t> v = {'t', 'r', 'u', 'e'}; +json j = json::parse(v.begin(), v.end()); +``` + +You may leave the iterators for the range [begin, end): + +```cpp +std::vector<std::uint8_t> v = {'t', 'r', 'u', 'e'}; +json j = json::parse(v); +``` + ### STL-like access @@ -192,6 +287,9 @@ j.push_back("foo"); j.push_back(1); j.push_back(true); +// also use emplace_back +j.emplace_back(1.78); + // iterate the array for (json::iterator it = j.begin(); it != j.end(); ++it) { std::cout << *it << '\n'; @@ -207,6 +305,9 @@ const std::string tmp = j[0]; j[1] = 42; bool foo = j.at(2); +// comparison +j == "[\"foo\", 1, true]"_json; // true + // other stuff j.size(); // 3 entries j.empty(); // false @@ -221,15 +322,15 @@ j.is_object(); j.is_array(); j.is_string(); -// comparison -j == "[\"foo\", 1, true]"_json; // true - // create an object json o; o["foo"] = 23; o["bar"] = false; o["baz"] = 3.141; +// also use emplace +o.emplace("weather", "sunny"); + // special iterator member functions for objects for (json::iterator it = o.begin(); it != o.end(); ++it) { std::cout << it.key() << " : " << it.value() << "\n"; @@ -251,7 +352,7 @@ o.erase("foo"); ### Conversion from STL containers -Any sequence container (`std::array`, `std::vector`, `std::deque`, `std::forward_list`, `std::list`) whose values can be used to construct JSON types (e.g., integers, floating point numbers, Booleans, string types, or again STL containers described in this section) can be used to create a JSON array. The same holds for similar associative containers (`std::set`, `std::multiset`, `std::unordered_set`, `std::unordered_multiset`), but in these cases the order of the elements of the array depends how the elements are ordered in the respective STL container. +Any sequence container (`std::array`, `std::vector`, `std::deque`, `std::forward_list`, `std::list`) whose values can be used to construct JSON types (e.g., integers, floating point numbers, Booleans, string types, or again STL containers described in this section) can be used to create a JSON array. The same holds for similar associative containers (`std::set`, `std::multiset`, `std::unordered_set`, `std::unordered_multiset`), but in these cases the order of the elements of the array depends on how the elements are ordered in the respective STL container. ```cpp std::vector<int> c_vector {1, 2, 3, 4}; @@ -283,15 +384,15 @@ json j_uset(c_uset); // only one entry for "one" is used // maybe ["two", "three", "four", "one"] std::multiset<std::string> c_mset {"one", "two", "one", "four"}; -json j_mset(c_mset); // only one entry for "one" is used -// maybe ["one", "two", "four"] +json j_mset(c_mset); // both entries for "one" are used +// maybe ["one", "two", "one", "four"] std::unordered_multiset<std::string> c_umset {"one", "two", "one", "four"}; json j_umset(c_umset); // both entries for "one" are used // maybe ["one", "two", "one", "four"] ``` -Likewise, any associative key-value containers (`std::map`, `std::multimap`, `std::unordered_map`, `std::unordered_multimap`) whose keys are can construct an `std::string` and whose values can be used to construct JSON types (see examples above) can be used to to create a JSON object. Note that in case of multimaps only one key is used in the JSON object and the value depends on the internal order of the STL container. +Likewise, any associative key-value containers (`std::map`, `std::multimap`, `std::unordered_map`, `std::unordered_multimap`) whose keys can construct an `std::string` and whose values can be used to construct JSON types (see examples above) can be used to create a JSON object. Note that in case of multimaps only one key is used in the JSON object and the value depends on the internal order of the STL container. ```cpp std::map<std::string, int> c_map { {"one", 1}, {"two", 2}, {"three", 3} }; @@ -323,7 +424,7 @@ json j_original = R"({ })"_json; // access members with a JSON pointer (RFC 6901) -j_original["/baz/2"_json_pointer]; +j_original["/baz/1"_json_pointer]; // "two" // a JSON patch (RFC 6902) @@ -344,8 +445,8 @@ json j_result = j_original.patch(j_patch); json::diff(j_result, j_original); // [ // { "op":" replace", "path": "/baz", "value": ["one", "two", "three"] }, -// { "op":"remove","path":"/hello" }, -// { "op":"add","path":"/foo","value":"bar" } +// { "op": "remove","path": "/hello" }, +// { "op": "add", "path": "/foo", "value": "bar" } // ] ``` @@ -383,14 +484,266 @@ int vi = jn.get<int>(); // etc. ``` +### Arbitrary types conversions + +Every type can be serialized in JSON, not just STL-containers and scalar types. Usually, you would do something along those lines: + +```cpp +namespace ns { + // a simple struct to model a person + struct person { + std::string name; + std::string address; + int age; + }; +} + +ns::person p = {"Ned Flanders", "744 Evergreen Terrace", 60}; + +// convert to JSON: copy each value into the JSON object +json j; +j["name"] = p.name; +j["address"] = p.address; +j["age"] = p.age; + +// ... + +// convert from JSON: copy each value from the JSON object +ns::person p { + j["name"].get<std::string>(), + j["address"].get<std::string>(), + j["age"].get<int>() +}; +``` + +It works, but that's quite a lot of boilerplate... Fortunately, there's a better way: + +```cpp +// create a person +ns::person p {"Ned Flanders", "744 Evergreen Terrace", 60}; + +// conversion: person -> json +json j = p; + +std::cout << j << std::endl; +// {"address":"744 Evergreen Terrace","age":60,"name":"Ned Flanders"} + +// conversion: json -> person +ns::person p2 = j; + +// that's it +assert(p == p2); +``` + +#### Basic usage + +To make this work with one of your types, you only need to provide two functions: + +```cpp +using nlohmann::json; + +namespace ns { + void to_json(json& j, const person& p) { + j = json{{"name", p.name}, {"address", p.address}, {"age", p.age}}; + } + + void from_json(const json& j, person& p) { + p.name = j.at("name").get<std::string>(); + p.address = j.at("address").get<std::string>(); + p.age = j.at("age").get<int>(); + } +} // namespace ns +``` + +That's all! When calling the `json` constructor with your type, your custom `to_json` method will be automatically called. +Likewise, when calling `get<your_type>()`, the `from_json` method will be called. + +Some important things: + +* Those methods **MUST** be in your type's namespace (which can be the global namespace), or the library will not be able to locate them (in this example, they are in namespace `ns`, where `person` is defined). +* When using `get<your_type>()`, `your_type` **MUST** be [DefaultConstructible](http://en.cppreference.com/w/cpp/concept/DefaultConstructible). (There is a way to bypass this requirement described later.) +* In function `from_json`, use function [`at()`](https://nlohmann.github.io/json/classnlohmann_1_1basic__json_a93403e803947b86f4da2d1fb3345cf2c.html#a93403e803947b86f4da2d1fb3345cf2c) to access the object values rather than `operator[]`. In case a key does not exist, `at` throws an exception that you can handle, whereas `operator[]` exhibits undefined behavior. +* In case your type contains several `operator=` definitions, code like `your_variable = your_json;` [may not compile](https://github.com/nlohmann/json/issues/667). You need to write `your_variable = your_json.get<decltype your_variable>();` instead. +* You do not need to add serializers or deserializers for STL types like `std::vector`: the library already implements these. +* Be careful with the definition order of the `from_json`/`to_json` functions: If a type `B` has a member of type `A`, you **MUST** define `to_json(A)` before `to_json(B)`. Look at [issue 561](https://github.com/nlohmann/json/issues/561) for more details. + + +#### How do I convert third-party types? + +This requires a bit more advanced technique. But first, let's see how this conversion mechanism works: + +The library uses **JSON Serializers** to convert types to json. +The default serializer for `nlohmann::json` is `nlohmann::adl_serializer` (ADL means [Argument-Dependent Lookup](http://en.cppreference.com/w/cpp/language/adl)). + +It is implemented like this (simplified): + +```cpp +template <typename T> +struct adl_serializer { + static void to_json(json& j, const T& value) { + // calls the "to_json" method in T's namespace + } + + static void from_json(const json& j, T& value) { + // same thing, but with the "from_json" method + } +}; +``` + +This serializer works fine when you have control over the type's namespace. However, what about `boost::optional`, or `std::filesystem::path` (C++17)? Hijacking the `boost` namespace is pretty bad, and it's illegal to add something other than template specializations to `std`... + +To solve this, you need to add a specialization of `adl_serializer` to the `nlohmann` namespace, here's an example: + +```cpp +// partial specialization (full specialization works too) +namespace nlohmann { + template <typename T> + struct adl_serializer<boost::optional<T>> { + static void to_json(json& j, const boost::optional<T>& opt) { + if (opt == boost::none) { + j = nullptr; + } else { + j = *opt; // this will call adl_serializer<T>::to_json which will + // find the free function to_json in T's namespace! + } + } + + static void from_json(const json& j, boost::optional<T>& opt) { + if (j.is_null()) { + opt = boost::none; + } else { + opt = j.get<T>(); // same as above, but with + // adl_serializer<T>::from_json + } + } + }; +} +``` + +#### How can I use `get()` for non-default constructible/non-copyable types? + +There is a way, if your type is [MoveConstructible](http://en.cppreference.com/w/cpp/concept/MoveConstructible). You will need to specialize the `adl_serializer` as well, but with a special `from_json` overload: + +```cpp +struct move_only_type { + move_only_type() = delete; + move_only_type(int ii): i(ii) {} + move_only_type(const move_only_type&) = delete; + move_only_type(move_only_type&&) = default; + + int i; +}; + +namespace nlohmann { + template <> + struct adl_serializer<move_only_type> { + // note: the return type is no longer 'void', and the method only takes + // one argument + static move_only_type from_json(const json& j) { + return {j.get<int>()}; + } + + // Here's the catch! You must provide a to_json method! Otherwise you + // will not be able to convert move_only_type to json, since you fully + // specialized adl_serializer on that type + static void to_json(json& j, move_only_type t) { + j = t.i; + } + }; +} +``` + +#### Can I write my own serializer? (Advanced use) + +Yes. You might want to take a look at [`unit-udt.cpp`](https://github.com/nlohmann/json/blob/develop/test/src/unit-udt.cpp) in the test suite, to see a few examples. + +If you write your own serializer, you'll need to do a few things: + +* use a different `basic_json` alias than `nlohmann::json` (the last template parameter of `basic_json` is the `JSONSerializer`) +* use your `basic_json` alias (or a template parameter) in all your `to_json`/`from_json` methods +* use `nlohmann::to_json` and `nlohmann::from_json` when you need ADL + +Here is an example, without simplifications, that only accepts types with a size <= 32, and uses ADL. + +```cpp +// You should use void as a second template argument +// if you don't need compile-time checks on T +template<typename T, typename SFINAE = typename std::enable_if<sizeof(T) <= 32>::type> +struct less_than_32_serializer { + template <typename BasicJsonType> + static void to_json(BasicJsonType& j, T value) { + // we want to use ADL, and call the correct to_json overload + using nlohmann::to_json; // this method is called by adl_serializer, + // this is where the magic happens + to_json(j, value); + } + + template <typename BasicJsonType> + static void from_json(const BasicJsonType& j, T& value) { + // same thing here + using nlohmann::from_json; + from_json(j, value); + } +}; +``` + +Be **very** careful when reimplementing your serializer, you can stack overflow if you don't pay attention: + +```cpp +template <typename T, void> +struct bad_serializer +{ + template <typename BasicJsonType> + static void to_json(BasicJsonType& j, const T& value) { + // this calls BasicJsonType::json_serializer<T>::to_json(j, value); + // if BasicJsonType::json_serializer == bad_serializer ... oops! + j = value; + } + + template <typename BasicJsonType> + static void to_json(const BasicJsonType& j, T& value) { + // this calls BasicJsonType::json_serializer<T>::from_json(j, value); + // if BasicJsonType::json_serializer == bad_serializer ... oops! + value = j.template get<T>(); // oops! + } +}; +``` + +### Binary formats (CBOR and MessagePack) + +Though JSON is a ubiquitous data format, it is not a very compact format suitable for data exchange, for instance over a network. Hence, the library supports [CBOR](http://cbor.io) (Concise Binary Object Representation) and [MessagePack](http://msgpack.org) to efficiently encode JSON values to byte vectors and to decode such vectors. + +```cpp +// create a JSON value +json j = R"({"compact": true, "schema": 0})"_json; + +// serialize to CBOR +std::vector<std::uint8_t> v_cbor = json::to_cbor(j); + +// 0xa2, 0x67, 0x63, 0x6f, 0x6d, 0x70, 0x61, 0x63, 0x74, 0xf5, 0x66, 0x73, 0x63, 0x68, 0x65, 0x6d, 0x61, 0x00 + +// roundtrip +json j_from_cbor = json::from_cbor(v_cbor); + +// serialize to MessagePack +std::vector<std::uint8_t> v_msgpack = json::to_msgpack(j); + +// 0x82, 0xa7, 0x63, 0x6f, 0x6d, 0x70, 0x61, 0x63, 0x74, 0xc3, 0xa6, 0x73, 0x63, 0x68, 0x65, 0x6d, 0x61, 0x00 + +// roundtrip +json j_from_msgpack = json::from_msgpack(v_msgpack); +``` + ## Supported compilers -Though it's 2016 already, the support for C++11 is still a bit sparse. Currently, the following compilers are known to work: +Though it's 2017 already, the support for C++11 is still a bit sparse. Currently, the following compilers are known to work: -- GCC 4.9 - 6.0 (and possibly later) -- Clang 3.4 - 3.9 (and possibly later) -- Microsoft Visual C++ 2015 / 14.0 (and possibly later) +- GCC 4.9 - 7.2 (and possibly later) +- Clang 3.4 - 5.0 (and possibly later) +- Intel C++ Compiler 17.0.2 (and possibly later) +- Microsoft Visual C++ 2015 / Build Tools 14.0.25123.0 (and possibly later) +- Microsoft Visual C++ 2017 / Build Tools 15.5.180.51428 (and possibly later) I would be happy to learn about other compilers/versions. @@ -413,20 +766,28 @@ The following compilers are currently used in continuous integration at [Travis] | Compiler | Operating System | Version String | |-----------------|------------------------------|----------------| -| GCC 4.9.3 | Ubuntu 14.04.4 LTS | g++-4.9 (Ubuntu 4.9.3-8ubuntu2~14.04) 4.9.3 | -| GCC 5.3.0 | Ubuntu 14.04.4 LTS | g++-5 (Ubuntu 5.3.0-3ubuntu1~14.04) 5.3.0 20151204 | -| GCC 6.1.1 | Ubuntu 14.04.4 LTS | g++-6 (Ubuntu 6.1.1-3ubuntu11~14.04.1) 6.1.1 20160511 | -| Clang 3.8.0 | Ubuntu 14.04.4 LTS | clang version 3.8.0 (tags/RELEASE_380/final) | -| Clang Xcode 6.1 | Darwin Kernel Version 13.4.0 (OSX 10.9.5) | Apple LLVM version 6.0 (clang-600.0.54) (based on LLVM 3.5svn) | -| Clang Xcode 6.2 | Darwin Kernel Version 13.4.0 (OSX 10.9.5) | Apple LLVM version 6.0 (clang-600.0.57) (based on LLVM 3.5svn) | -| Clang Xcode 6.3 | Darwin Kernel Version 14.3.0 (OSX 10.10.3) | Apple LLVM version 6.1.0 (clang-602.0.49) (based on LLVM 3.6.0svn) | +| GCC 4.9.4 | Ubuntu 14.04.5 LTS | g++-4.9 (Ubuntu 4.9.4-2ubuntu1~14.04.1) 4.9.4 | +| GCC 5.4.1 | Ubuntu 14.04.5 LTS | g++-5 (Ubuntu 5.4.1-2ubuntu1~14.04) 5.4.1 20160904 | +| GCC 6.3.0 | Ubuntu 14.04.5 LTS | g++-6 (Ubuntu/Linaro 6.3.0-18ubuntu2~14.04) 6.3.0 20170519 | +| GCC 7.1.0 | Ubuntu 14.04.5 LTS | g++-7 (Ubuntu 7.1.0-5ubuntu2~14.04) 7.1.0 +| Clang 3.5.0 | Ubuntu 14.04.5 LTS | clang version 3.5.0-4ubuntu2~trusty2 (tags/RELEASE_350/final) | +| Clang 3.6.2 | Ubuntu 14.04.5 LTS | clang version 3.6.2-svn240577-1~exp1 (branches/release_36) | +| Clang 3.7.1 | Ubuntu 14.04.5 LTS | clang version 3.7.1-svn253571-1~exp1 (branches/release_37) | +| Clang 3.8.0 | Ubuntu 14.04.5 LTS | clang version 3.8.0-2ubuntu3~trusty5 (tags/RELEASE_380/final) | +| Clang 3.9.1 | Ubuntu 14.04.5 LTS | clang version 3.9.1-4ubuntu3~14.04.2 (tags/RELEASE_391/rc2) | +| Clang 4.0.1 | Ubuntu 14.04.5 LTS | clang version 4.0.1-svn305264-1~exp1 (branches/release_40) | +| Clang 5.0.0 | Ubuntu 14.04.5 LTS | clang version 5.0.0-svn310902-1~exp1 (branches/release_50) | | Clang Xcode 6.4 | Darwin Kernel Version 14.3.0 (OSX 10.10.3) | Apple LLVM version 6.1.0 (clang-602.0.53) (based on LLVM 3.6.0svn) | -| Clang Xcode 7.1 | Darwin Kernel Version 14.5.0 (OSX 10.10.5) | Apple LLVM version 7.0.0 (clang-700.1.76) | -| Clang Xcode 7.2 | Darwin Kernel Version 15.0.0 (OSX 10.10.5) | Apple LLVM version 7.0.2 (clang-700.1.81) | | Clang Xcode 7.3 | Darwin Kernel Version 15.0.0 (OSX 10.10.5) | Apple LLVM version 7.3.0 (clang-703.0.29) | -| Clang Xcode 8.0 | Darwin Kernel Version 15.5.0 (OSX 10.11.5) | Apple LLVM version 8.0.0 (clang-800.0.24.1) | -| Visual Studio 14 2015 | Windows Server 2012 R2 (x64) | Microsoft (R) Build Engine version 14.0.25123.0 | - +| Clang Xcode 8.0 | Darwin Kernel Version 15.6.0 | Apple LLVM version 8.0.0 (clang-800.0.38) | +| Clang Xcode 8.1 | Darwin Kernel Version 16.1.0 (macOS 10.12.1) | Apple LLVM version 8.0.0 (clang-800.0.42.1) | +| Clang Xcode 8.2 | Darwin Kernel Version 16.1.0 (macOS 10.12.1) | Apple LLVM version 8.0.0 (clang-800.0.42.1) | +| Clang Xcode 8.3 | Darwin Kernel Version 16.5.0 (macOS 10.12.4) | Apple LLVM version 8.1.0 (clang-802.0.38) | +| Clang Xcode 9.0 | Darwin Kernel Version 16.7.0 (macOS 10.12.6) | Apple LLVM version 9.0.0 (clang-900.0.37) | +| Clang Xcode 9.1 | Darwin Kernel Version 16.7.0 (macOS 10.12.6) | Apple LLVM version 9.0.0 (clang-900.0.38) | +| Clang Xcode 9.2 | Darwin Kernel Version 16.7.0 (macOS 10.12.6) | Apple LLVM version 8.1.0 (clang-900.0.39.2) | +| Visual Studio 14 2015 | Windows Server 2012 R2 (x64) | Microsoft (R) Build Engine version 14.0.25420.1, MSVC 19.0.24215.1 | +| Visual Studio 2017 | Windows Server 2016 | Microsoft (R) Build Engine version 15.5.180.51428, MSVC 19.12.25830.2 | ## License @@ -434,7 +795,7 @@ The following compilers are currently used in continuous integration at [Travis] The class is licensed under the [MIT License](http://opensource.org/licenses/MIT): -Copyright © 2013-2016 [Niels Lohmann](http://nlohmann.me) +Copyright © 2013-2017 [Niels Lohmann](http://nlohmann.me) Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the “Software”), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions: @@ -442,11 +803,23 @@ The above copyright notice and this permission notice shall be included in all c THE SOFTWARE IS PROVIDED “AS IS”, WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. +* * * + +The class contains the UTF-8 Decoder from Bjoern Hoehrmann which is licensed under the [MIT License](http://opensource.org/licenses/MIT) (see above). Copyright © 2008-2009 [Björn Hoehrmann](http://bjoern.hoehrmann.de/) <bjoern@hoehrmann.de> + +## Contact + +If you have questions regarding the library, I would like to invite you to [open an issue at Github](https://github.com/nlohmann/json/issues/new). Please describe your request, problem, or question as detailed as possible, and also mention the version of the library you are using as well as the version of your compiler and operating system. Opening an issue at Github allows other users and contributors to this library to collaborate. For instance, I have little experience with MSVC, and most issues in this regard have been solved by a growing community. If you have a look at the [closed issues](https://github.com/nlohmann/json/issues?q=is%3Aissue+is%3Aclosed), you will see that we react quite timely in most cases. + +Only if your request would contain confidential information, please [send me an email](mailto:mail@nlohmann.me). For encrypted messages, please use [this key](https://keybase.io/nlohmann/pgp_keys.asc). + ## Thanks I deeply appreciate the help of the following people. + + - [Teemperor](https://github.com/Teemperor) implemented CMake support and lcov integration, realized escape and Unicode handling in the string parser, and fixed the JSON serialization. - [elliotgoodrich](https://github.com/elliotgoodrich) fixed an issue with double deletion in the iterator classes. - [kirkshoop](https://github.com/kirkshoop) made the iterators of the class composable to other libraries. @@ -459,7 +832,7 @@ I deeply appreciate the help of the following people. - [Eric Cornelius](https://github.com/EricMCornelius) pointed out a bug in the handling with NaN and infinity values. He also improved the performance of the string escaping. - [易思龙](https://github.com/likebeta) implemented a conversion from anonymous enums. - [kepkin](https://github.com/kepkin) patiently pushed forward the support for Microsoft Visual studio. -- [gregmarr](https://github.com/gregmarr) simplified the implementation of reverse iterators and helped with numerous hints and improvements. +- [gregmarr](https://github.com/gregmarr) simplified the implementation of reverse iterators and helped with numerous hints and improvements. In particular, he pushed forward the implementation of user-defined types. - [Caio Luppi](https://github.com/caiovlp) fixed a bug in the Unicode handling. - [dariomt](https://github.com/dariomt) fixed some typos in the examples. - [Daniel Frey](https://github.com/d-frey) cleaned up some pointers and implemented exception-safe memory allocation. @@ -483,14 +856,117 @@ I deeply appreciate the help of the following people. - [Róbert Márki](https://github.com/robertmrk) added a fix to use move iterators and improved the integration via CMake. - [Chris Kitching](https://github.com/ChrisKitching) cleaned up the CMake files. - [Tom Needham](https://github.com/06needhamt) fixed a subtle bug with MSVC 2015 which was also proposed by [Michael K.](https://github.com/Epidal). - -Thanks a lot for helping out! +- [Mário Feroldi](https://github.com/thelostt) fixed a small typo. +- [duncanwerner](https://github.com/duncanwerner) found a really embarrassing performance regression in the 2.0.0 release. +- [Damien](https://github.com/dtoma) fixed one of the last conversion warnings. +- [Thomas Braun](https://github.com/t-b) fixed a warning in a test case. +- [Théo DELRIEU](https://github.com/theodelrieu) patiently and constructively oversaw the long way toward [iterator-range parsing](https://github.com/nlohmann/json/issues/290). He also implemented the magic behind the serialization/deserialization of user-defined types. +- [Stefan](https://github.com/5tefan) fixed a minor issue in the documentation. +- [Vasil Dimov](https://github.com/vasild) fixed the documentation regarding conversions from `std::multiset`. +- [ChristophJud](https://github.com/ChristophJud) overworked the CMake files to ease project inclusion. +- [Vladimir Petrigo](https://github.com/vpetrigo) made a SFINAE hack more readable and added Visual Studio 17 to the build matrix. +- [Denis Andrejew](https://github.com/seeekr) fixed a grammar issue in the README file. +- [Pierre-Antoine Lacaze](https://github.com/palacaze) found a subtle bug in the `dump()` function. +- [TurpentineDistillery](https://github.com/TurpentineDistillery) pointed to [`std::locale::classic()`](http://en.cppreference.com/w/cpp/locale/locale/classic) to avoid too much locale joggling, found some nice performance improvements in the parser, improved the benchmarking code, and realized locale-independent number parsing and printing. +- [cgzones](https://github.com/cgzones) had an idea how to fix the Coverity scan. +- [Jared Grubb](https://github.com/jaredgrubb) silenced a nasty documentation warning. +- [Yixin Zhang](https://github.com/qwename) fixed an integer overflow check. +- [Bosswestfalen](https://github.com/Bosswestfalen) merged two iterator classes into a smaller one. +- [Daniel599](https://github.com/Daniel599) helped to get Travis execute the tests with Clang's sanitizers. +- [Jonathan Lee](https://github.com/vjon) fixed an example in the README file. +- [gnzlbg](https://github.com/gnzlbg) supported the implementation of user-defined types. +- [Alexej Harm](https://github.com/qis) helped to get the user-defined types working with Visual Studio. +- [Jared Grubb](https://github.com/jaredgrubb) supported the implementation of user-defined types. +- [EnricoBilla](https://github.com/EnricoBilla) noted a typo in an example. +- [Martin Hořeňovský](https://github.com/horenmar) found a way for a 2x speedup for the compilation time of the test suite. +- [ukhegg](https://github.com/ukhegg) found proposed an improvement for the examples section. +- [rswanson-ihi](https://github.com/rswanson-ihi) noted a typo in the README. +- [Mihai Stan](https://github.com/stanmihai4) fixed a bug in the comparison with `nullptr`s. +- [Tushar Maheshwari](https://github.com/tusharpm) added [cotire](https://github.com/sakra/cotire) support to speed up the compilation. +- [TedLyngmo](https://github.com/TedLyngmo) noted a typo in the README, removed unnecessary bit arithmetic, and fixed some `-Weffc++` warnings. +- [Krzysztof Woś](https://github.com/krzysztofwos) made exceptions more visible. +- [ftillier](https://github.com/ftillier) fixed a compiler warning. +- [tinloaf](https://github.com/tinloaf) made sure all pushed warnings are properly popped. +- [Fytch](https://github.com/Fytch) found a bug in the documentation. +- [Jay Sistar](https://github.com/Type1J) implemented a Meson build description. +- [Henry Lee](https://github.com/HenryRLee) fixed a warning in ICC and improved the iterator implementation. +- [Vincent Thiery](https://github.com/vthiery) maintains a package for the Conan package manager. +- [Steffen](https://github.com/koemeet) fixed a potential issue with MSVC and `std::min`. +- [Mike Tzou](https://github.com/Chocobo1) fixed some typos. +- [amrcode](https://github.com/amrcode) noted a missleading documentation about comparison of floats. +- [Oleg Endo](https://github.com/olegendo) reduced the memory consumption by replacing `<iostream>` with `<iosfwd>`. +- [dan-42](https://github.com/dan-42) cleaned up the CMake files to simplify including/reusing of the library. +- [Nikita Ofitserov](https://github.com/himikof) allowed for moving values from initializer lists. +- [Greg Hurrell](https://github.com/wincent) fixed a typo. +- [Dmitry Kukovinets](https://github.com/DmitryKuk) fixed a typo. +- [kbthomp1](https://github.com/kbthomp1) fixed an issue related to the Intel OSX compiler. +- [Markus Werle](https://github.com/daixtrose) fixed a typo. +- [WebProdPP](https://github.com/WebProdPP) fixed a subtle error in a precondition check. +- [Alex](https://github.com/leha-bot) noted an error in a code sample. +- [Tom de Geus](https://github.com/tdegeus) reported some warnings with ICC and helped fixing them. +- [Perry Kundert](https://github.com/pjkundert) simplified reading from input streams. +- [Sonu Lohani](https://github.com/sonulohani) fixed a small compilation error. +- [Jamie Seward](https://github.com/jseward) fixed all MSVC warnings. +- [Nate Vargas](https://github.com/eld00d) added a Doxygen tag file. +- [pvleuven](https://github.com/pvleuven) helped fixing a warning in ICC. +- [Pavel](https://github.com/crea7or) helped fixing some warnings in MSVC. +- [Jamie Seward](https://github.com/jseward) avoided unneccessary string copies in `find()` and `count()`. +- [Mitja](https://github.com/Itja) fixed some typos. +- [Jorrit Wronski](https://github.com/jowr) updated the Hunter package links. +- [Matthias Möller](https://github.com/TinyTinni) added a `.natvis` for the MSVC debug view. +- [bogemic](https://github.com/bogemic) fixed some C++17 deprecation warnings. +- [Eren Okka](https://github.com/erengy) fixed some MSVC warnings. + + +Thanks a lot for helping out! Please [let me know](mailto:mail@nlohmann.me) if I forgot someone. + + +## Used third-party tools + +The library itself contains of a single header file licensed under the MIT license. However, it is built, tested, documented, and whatnot using a lot of third-party tools and services. Thanks a lot! + +- [**American fuzzy lop**](http://lcamtuf.coredump.cx/afl/) for fuzz testing +- [**AppVeyor**](https://www.appveyor.com) for [continuous integration](https://ci.appveyor.com/project/nlohmann/json) on Windows +- [**Artistic Style**](http://astyle.sourceforge.net) for automatic source code identation +- [**benchpress**](https://github.com/sbs-ableton/benchpress) to benchmark the code +- [**Catch**](https://github.com/philsquared/Catch) for the unit tests +- [**Clang**](http://clang.llvm.org) for compilation with code sanitizers +- [**Cmake**](https://cmake.org) for build automation +- [**Codacity**](https://www.codacy.com) for further [code analysis](https://www.codacy.com/app/nlohmann/json) +- [**Coveralls**](https://coveralls.io) to measure [code coverage](https://coveralls.io/github/nlohmann/json) +- [**Coverity Scan**](https://scan.coverity.com) for [static analysis](https://scan.coverity.com/projects/nlohmann-json) +- [**cppcheck**](http://cppcheck.sourceforge.net) for static analysis +- [**cxxopts**](https://github.com/jarro2783/cxxopts) to let benchpress parse command-line parameters +- [**Doxygen**](http://www.stack.nl/~dimitri/doxygen/) to generate [documentation](https://nlohmann.github.io/json/) +- [**git-update-ghpages**](https://github.com/rstacruz/git-update-ghpages) to upload the documentation to gh-pages +- [**Github Changelog Generator**](https://github.com/skywinder/github-changelog-generator) to generate the [ChangeLog](https://github.com/nlohmann/json/blob/develop/ChangeLog.md) +- [**libFuzzer**](http://llvm.org/docs/LibFuzzer.html) to implement fuzz testing for OSS-Fuzz +- [**OSS-Fuzz**](https://github.com/google/oss-fuzz) for continuous fuzz testing of the library +- [**Probot**](https://probot.github.io) for automating maintainer tasks such as closing stale issues, requesting missing information, or detecting toxic comments. +- [**send_to_wandbox**](https://github.com/nlohmann/json/blob/develop/doc/scripts/send_to_wandbox.py) to send code examples to [Wandbox](http://melpon.org/wandbox) +- [**Travis**](https://travis-ci.org) for [continuous integration](https://travis-ci.org/nlohmann/json) on Linux and macOS +- [**Valgrind**](http://valgrind.org) to check for correct memory management +- [**Wandbox**](http://melpon.org/wandbox) for [online examples](https://wandbox.org/permlink/Op57X0V7fTf2tdwl) + + +## Projects using JSON for Modern C++ + +The library is currently used in Apple macOS Sierra and iOS 10. I am not sure what they are using the library for, but I am happy that it runs on so many devices. ## Notes -- The code contains numerous debug **assertions** which can be switched off by defining the preprocessor macro `NDEBUG`, see the [documentation of `assert`](http://en.cppreference.com/w/cpp/error/assert). +- The code contains numerous debug **assertions** which can be switched off by defining the preprocessor macro `NDEBUG`, see the [documentation of `assert`](http://en.cppreference.com/w/cpp/error/assert). In particular, note [`operator[]`](https://nlohmann.github.io/json/classnlohmann_1_1basic__json_a2e26bd0b0168abb61f67ad5bcd5b9fa1.html#a2e26bd0b0168abb61f67ad5bcd5b9fa1) implements **unchecked access** for const objects: If the given key is not present, the behavior is undefined (think of a dereferenced null pointer) and yields an [assertion failure](https://github.com/nlohmann/json/issues/289) if assertions are switched on. If you are not sure whether an element in an object exists, use checked access with the [`at()` function](https://nlohmann.github.io/json/classnlohmann_1_1basic__json_a674de1ee73e6bf4843fc5dc1351fb726.html#a674de1ee73e6bf4843fc5dc1351fb726). - As the exact type of a number is not defined in the [JSON specification](http://rfc7159.net/rfc7159), this library tries to choose the best fitting C++ number type automatically. As a result, the type `double` may be used to store numbers which may yield [**floating-point exceptions**](https://github.com/nlohmann/json/issues/181) in certain rare situations if floating-point exceptions have been unmasked in the calling code. These exceptions are not caused by the library and need to be fixed in the calling code, such as by re-masking the exceptions prior to calling library functions. +- The library supports **Unicode input** as follows: + - Only **UTF-8** encoded input is supported which is the default encoding for JSON according to [RFC 7159](http://rfc7159.net/rfc7159#rfc.section.8.1). + - Other encodings such as Latin-1, UTF-16, or UTF-32 are not supported and will yield parse or serialization errors. + - [Unicode noncharacters](http://www.unicode.org/faq/private_use.html#nonchar1) will not be replaced by the library. + - Invalid surrogates (e.g., incomplete pairs such as `\uDEAD`) will yield parse errors. + - The strings stored in the library are UTF-8 encoded. When using the default string type (`std::string`), note that its length/size functions return the number of stored bytes rather than the number of characters or glyphs. +- The code can be compiled without C++ **runtime type identification** features; that is, you can use the `-fno-rtti` compiler flag. +- **Exceptions** are used widely within the library. They can, however, be switched off with either using the compiler flag `-fno-exceptions` or by defining the symbol `JSON_NOEXCEPTION`. In this case, exceptions are replaced by an `abort()` call. +- By default, the library does not preserve the **insertion order of object elements**. This is standards-compliant, as the [JSON standard](https://tools.ietf.org/html/rfc7159.html) defines objects as "an unordered collection of zero or more name/value pairs". If you do want to preserve the insertion order, you can specialize the object type with containers like [`tsl::ordered_map`](https://github.com/Tessil/ordered-map) ([integration](https://github.com/nlohmann/json/issues/546#issuecomment-304447518)) or [`nlohmann::fifo_map`](https://github.com/nlohmann/fifo_map) ([integration](https://github.com/nlohmann/json/issues/485#issuecomment-333652309)). ## Execute unit tests @@ -498,11 +974,11 @@ Thanks a lot for helping out! To compile and run the tests, you need to execute ```sh -$ make -$ ./json_unit "*" - -=============================================================================== -All tests passed (5568721 assertions in 32 test cases) +$ mkdir build +$ cd build +$ cmake .. +$ cmake --build . +$ ctest --output-on-failure ``` For more information, have a look at the file [.travis.yml](https://github.com/nlohmann/json/blob/master/.travis.yml). diff --git a/ext/json/json.hpp b/ext/json/json.hpp index 9d6687dd..5b0b0ea5 100644 --- a/ext/json/json.hpp +++ b/ext/json/json.hpp @@ -1,11 +1,11 @@ /* __ _____ _____ _____ __| | __| | | | JSON for Modern C++ -| | |__ | | | | | | version 2.0.0 +| | |__ | | | | | | version 3.0.1 |_____|_____|_____|_|___| https://github.com/nlohmann/json Licensed under the MIT License <http://opensource.org/licenses/MIT>. -Copyright (c) 2013-2016 Niels Lohmann <http://nlohmann.me>. +Copyright (c) 2013-2017 Niels Lohmann <http://nlohmann.me>. Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal @@ -29,29 +29,44 @@ SOFTWARE. #ifndef NLOHMANN_JSON_HPP #define NLOHMANN_JSON_HPP -#include <algorithm> -#include <array> -#include <cassert> -#include <cerrno> -#include <ciso646> -#include <cmath> -#include <cstddef> -#include <cstdio> -#include <cstdlib> -#include <functional> -#include <initializer_list> -#include <iomanip> -#include <iostream> -#include <iterator> -#include <limits> -#include <map> -#include <memory> -#include <sstream> -#include <stdexcept> -#include <string> -#include <type_traits> -#include <utility> -#include <vector> +#include <algorithm> // all_of, copy, fill, find, for_each, generate_n, none_of, remove, reverse, transform +#include <array> // array +#include <cassert> // assert +#include <ciso646> // and, not, or +#include <clocale> // lconv, localeconv +#include <cmath> // isfinite, labs, ldexp, signbit +#include <cstddef> // nullptr_t, ptrdiff_t, size_t +#include <cstdint> // int64_t, uint64_t +#include <cstdlib> // abort, strtod, strtof, strtold, strtoul, strtoll, strtoull +#include <cstring> // memcpy, strlen +#include <forward_list> // forward_list +#include <functional> // function, hash, less +#include <initializer_list> // initializer_list +#include <iomanip> // hex +#include <iosfwd> // istream, ostream +#include <iterator> // advance, begin, back_inserter, bidirectional_iterator_tag, distance, end, inserter, iterator, iterator_traits, next, random_access_iterator_tag, reverse_iterator +#include <limits> // numeric_limits +#include <locale> // locale +#include <map> // map +#include <memory> // addressof, allocator, allocator_traits, unique_ptr +#include <numeric> // accumulate +#include <sstream> // stringstream +#include <string> // getline, stoi, string, to_string +#include <type_traits> // add_pointer, conditional, decay, enable_if, false_type, integral_constant, is_arithmetic, is_base_of, is_const, is_constructible, is_convertible, is_default_constructible, is_enum, is_floating_point, is_integral, is_nothrow_move_assignable, is_nothrow_move_constructible, is_pointer, is_reference, is_same, is_scalar, is_signed, remove_const, remove_cv, remove_pointer, remove_reference, true_type, underlying_type +#include <utility> // declval, forward, make_pair, move, pair, swap +#include <valarray> // valarray +#include <vector> // vector + +// exclude unsupported compilers +#if defined(__clang__) + #if (__clang_major__ * 10000 + __clang_minor__ * 100 + __clang_patchlevel__) < 30400 + #error "unsupported Clang version - see https://github.com/nlohmann/json#supported-compilers" + #endif +#elif defined(__GNUC__) && !(defined(__ICC) || defined(__INTEL_COMPILER)) + #if (__GNUC__ * 10000 + __GNUC_MINOR__ * 100 + __GNUC_PATCHLEVEL__) < 40900 + #error "unsupported GCC version - see https://github.com/nlohmann/json#supported-compilers" + #endif +#endif // disable float-equal warnings on GCC/clang #if defined(__clang__) || defined(__GNUC__) || defined(__GNUG__) @@ -59,6 +74,49 @@ SOFTWARE. #pragma GCC diagnostic ignored "-Wfloat-equal" #endif +// disable documentation warnings on clang +#if defined(__clang__) + #pragma GCC diagnostic push + #pragma GCC diagnostic ignored "-Wdocumentation" +#endif + +// allow for portable deprecation warnings +#if defined(__clang__) || defined(__GNUC__) || defined(__GNUG__) + #define JSON_DEPRECATED __attribute__((deprecated)) +#elif defined(_MSC_VER) + #define JSON_DEPRECATED __declspec(deprecated) +#else + #define JSON_DEPRECATED +#endif + +// allow to disable exceptions +#if (defined(__cpp_exceptions) || defined(__EXCEPTIONS) || defined(_CPPUNWIND)) && not defined(JSON_NOEXCEPTION) + #define JSON_THROW(exception) throw exception + #define JSON_TRY try + #define JSON_CATCH(exception) catch(exception) +#else + #define JSON_THROW(exception) std::abort() + #define JSON_TRY if(true) + #define JSON_CATCH(exception) if(false) +#endif + +// manual branch prediction +#if defined(__clang__) || defined(__GNUC__) || defined(__GNUG__) + #define JSON_LIKELY(x) __builtin_expect(!!(x), 1) + #define JSON_UNLIKELY(x) __builtin_expect(!!(x), 0) +#else + #define JSON_LIKELY(x) x + #define JSON_UNLIKELY(x) x +#endif + +// C++ language standard detection +#if (defined(__cplusplus) && __cplusplus >= 201703L) || (defined(_HAS_CXX17) && _HAS_CXX17 == 1) // fix for issue #464 + #define JSON_HAS_CPP_17 + #define JSON_HAS_CPP_14 +#elif (defined(__cplusplus) && __cplusplus >= 201402L) || (defined(_HAS_CXX14) && _HAS_CXX14 == 1) + #define JSON_HAS_CPP_14 +#endif + /*! @brief namespace for Niels Lohmann @see https://github.com/nlohmann @@ -66,43 +124,7163 @@ SOFTWARE. */ namespace nlohmann { +template<typename = void, typename = void> +struct adl_serializer; + +// forward declaration of basic_json (required to split the class) +template<template<typename, typename, typename...> class ObjectType = std::map, + template<typename, typename...> class ArrayType = std::vector, + class StringType = std::string, class BooleanType = bool, + class NumberIntegerType = std::int64_t, + class NumberUnsignedType = std::uint64_t, + class NumberFloatType = double, + template<typename> class AllocatorType = std::allocator, + template<typename, typename = void> class JSONSerializer = adl_serializer> +class basic_json; + +// Ugly macros to avoid uglier copy-paste when specializing basic_json. They +// may be removed in the future once the class is split. + +#define NLOHMANN_BASIC_JSON_TPL_DECLARATION \ + template<template<typename, typename, typename...> class ObjectType, \ + template<typename, typename...> class ArrayType, \ + class StringType, class BooleanType, class NumberIntegerType, \ + class NumberUnsignedType, class NumberFloatType, \ + template<typename> class AllocatorType, \ + template<typename, typename = void> class JSONSerializer> + +#define NLOHMANN_BASIC_JSON_TPL \ + basic_json<ObjectType, ArrayType, StringType, BooleanType, \ + NumberIntegerType, NumberUnsignedType, NumberFloatType, \ + AllocatorType, JSONSerializer> /*! @brief unnamed namespace with internal helper functions + +This namespace collects some functions that could not be defined inside the +@ref basic_json class. + +@since version 2.1.0 +*/ +namespace detail +{ +//////////////// +// exceptions // +//////////////// + +/*! +@brief general exception of the @ref basic_json class + +This class is an extension of `std::exception` objects with a member @a id for +exception ids. It is used as the base class for all exceptions thrown by the +@ref basic_json class. This class can hence be used as "wildcard" to catch +exceptions. + +Subclasses: +- @ref parse_error for exceptions indicating a parse error +- @ref invalid_iterator for exceptions indicating errors with iterators +- @ref type_error for exceptions indicating executing a member function with + a wrong type +- @ref out_of_range for exceptions indicating access out of the defined range +- @ref other_error for exceptions indicating other library errors + +@internal +@note To have nothrow-copy-constructible exceptions, we internally use + `std::runtime_error` which can cope with arbitrary-length error messages. + Intermediate strings are built with static functions and then passed to + the actual constructor. +@endinternal + +@liveexample{The following code shows how arbitrary library exceptions can be +caught.,exception} + +@since version 3.0.0 +*/ +class exception : public std::exception +{ + public: + /// returns the explanatory string + const char* what() const noexcept override + { + return m.what(); + } + + /// the id of the exception + const int id; + + protected: + exception(int id_, const char* what_arg) : id(id_), m(what_arg) {} + + static std::string name(const std::string& ename, int id_) + { + return "[json.exception." + ename + "." + std::to_string(id_) + "] "; + } + + private: + /// an exception object as storage for error messages + std::runtime_error m; +}; + +/*! +@brief exception indicating a parse error + +This exception is thrown by the library when a parse error occurs. Parse errors +can occur during the deserialization of JSON text, CBOR, MessagePack, as well +as when using JSON Patch. + +Member @a byte holds the byte index of the last read character in the input +file. + +Exceptions have ids 1xx. + +name / id | example message | description +------------------------------ | --------------- | ------------------------- +json.exception.parse_error.101 | parse error at 2: unexpected end of input; expected string literal | This error indicates a syntax error while deserializing a JSON text. The error message describes that an unexpected token (character) was encountered, and the member @a byte indicates the error position. +json.exception.parse_error.102 | parse error at 14: missing or wrong low surrogate | JSON uses the `\uxxxx` format to describe Unicode characters. Code points above above 0xFFFF are split into two `\uxxxx` entries ("surrogate pairs"). This error indicates that the surrogate pair is incomplete or contains an invalid code point. +json.exception.parse_error.103 | parse error: code points above 0x10FFFF are invalid | Unicode supports code points up to 0x10FFFF. Code points above 0x10FFFF are invalid. +json.exception.parse_error.104 | parse error: JSON patch must be an array of objects | [RFC 6902](https://tools.ietf.org/html/rfc6902) requires a JSON Patch document to be a JSON document that represents an array of objects. +json.exception.parse_error.105 | parse error: operation must have string member 'op' | An operation of a JSON Patch document must contain exactly one "op" member, whose value indicates the operation to perform. Its value must be one of "add", "remove", "replace", "move", "copy", or "test"; other values are errors. +json.exception.parse_error.106 | parse error: array index '01' must not begin with '0' | An array index in a JSON Pointer ([RFC 6901](https://tools.ietf.org/html/rfc6901)) may be `0` or any number without a leading `0`. +json.exception.parse_error.107 | parse error: JSON pointer must be empty or begin with '/' - was: 'foo' | A JSON Pointer must be a Unicode string containing a sequence of zero or more reference tokens, each prefixed by a `/` character. +json.exception.parse_error.108 | parse error: escape character '~' must be followed with '0' or '1' | In a JSON Pointer, only `~0` and `~1` are valid escape sequences. +json.exception.parse_error.109 | parse error: array index 'one' is not a number | A JSON Pointer array index must be a number. +json.exception.parse_error.110 | parse error at 1: cannot read 2 bytes from vector | When parsing CBOR or MessagePack, the byte vector ends before the complete value has been read. +json.exception.parse_error.112 | parse error at 1: error reading CBOR; last byte: 0xF8 | Not all types of CBOR or MessagePack are supported. This exception occurs if an unsupported byte was read. +json.exception.parse_error.113 | parse error at 2: expected a CBOR string; last byte: 0x98 | While parsing a map key, a value that is not a string has been read. + +@note For an input with n bytes, 1 is the index of the first character and n+1 + is the index of the terminating null byte or the end of file. This also + holds true when reading a byte vector (CBOR or MessagePack). + +@liveexample{The following code shows how a `parse_error` exception can be +caught.,parse_error} + +@sa @ref exception for the base class of the library exceptions +@sa @ref invalid_iterator for exceptions indicating errors with iterators +@sa @ref type_error for exceptions indicating executing a member function with + a wrong type +@sa @ref out_of_range for exceptions indicating access out of the defined range +@sa @ref other_error for exceptions indicating other library errors + +@since version 3.0.0 +*/ +class parse_error : public exception +{ + public: + /*! + @brief create a parse error exception + @param[in] id_ the id of the exception + @param[in] byte_ the byte index where the error occurred (or 0 if the + position cannot be determined) + @param[in] what_arg the explanatory string + @return parse_error object + */ + static parse_error create(int id_, std::size_t byte_, const std::string& what_arg) + { + std::string w = exception::name("parse_error", id_) + "parse error" + + (byte_ != 0 ? (" at " + std::to_string(byte_)) : "") + + ": " + what_arg; + return parse_error(id_, byte_, w.c_str()); + } + + /*! + @brief byte index of the parse error + + The byte index of the last read character in the input file. + + @note For an input with n bytes, 1 is the index of the first character and + n+1 is the index of the terminating null byte or the end of file. + This also holds true when reading a byte vector (CBOR or MessagePack). + */ + const std::size_t byte; + + private: + parse_error(int id_, std::size_t byte_, const char* what_arg) + : exception(id_, what_arg), byte(byte_) {} +}; + +/*! +@brief exception indicating errors with iterators + +This exception is thrown if iterators passed to a library function do not match +the expected semantics. + +Exceptions have ids 2xx. + +name / id | example message | description +----------------------------------- | --------------- | ------------------------- +json.exception.invalid_iterator.201 | iterators are not compatible | The iterators passed to constructor @ref basic_json(InputIT first, InputIT last) are not compatible, meaning they do not belong to the same container. Therefore, the range (@a first, @a last) is invalid. +json.exception.invalid_iterator.202 | iterator does not fit current value | In an erase or insert function, the passed iterator @a pos does not belong to the JSON value for which the function was called. It hence does not define a valid position for the deletion/insertion. +json.exception.invalid_iterator.203 | iterators do not fit current value | Either iterator passed to function @ref erase(IteratorType first, IteratorType last) does not belong to the JSON value from which values shall be erased. It hence does not define a valid range to delete values from. +json.exception.invalid_iterator.204 | iterators out of range | When an iterator range for a primitive type (number, boolean, or string) is passed to a constructor or an erase function, this range has to be exactly (@ref begin(), @ref end()), because this is the only way the single stored value is expressed. All other ranges are invalid. +json.exception.invalid_iterator.205 | iterator out of range | When an iterator for a primitive type (number, boolean, or string) is passed to an erase function, the iterator has to be the @ref begin() iterator, because it is the only way to address the stored value. All other iterators are invalid. +json.exception.invalid_iterator.206 | cannot construct with iterators from null | The iterators passed to constructor @ref basic_json(InputIT first, InputIT last) belong to a JSON null value and hence to not define a valid range. +json.exception.invalid_iterator.207 | cannot use key() for non-object iterators | The key() member function can only be used on iterators belonging to a JSON object, because other types do not have a concept of a key. +json.exception.invalid_iterator.208 | cannot use operator[] for object iterators | The operator[] to specify a concrete offset cannot be used on iterators belonging to a JSON object, because JSON objects are unordered. +json.exception.invalid_iterator.209 | cannot use offsets with object iterators | The offset operators (+, -, +=, -=) cannot be used on iterators belonging to a JSON object, because JSON objects are unordered. +json.exception.invalid_iterator.210 | iterators do not fit | The iterator range passed to the insert function are not compatible, meaning they do not belong to the same container. Therefore, the range (@a first, @a last) is invalid. +json.exception.invalid_iterator.211 | passed iterators may not belong to container | The iterator range passed to the insert function must not be a subrange of the container to insert to. +json.exception.invalid_iterator.212 | cannot compare iterators of different containers | When two iterators are compared, they must belong to the same container. +json.exception.invalid_iterator.213 | cannot compare order of object iterators | The order of object iterators cannot be compared, because JSON objects are unordered. +json.exception.invalid_iterator.214 | cannot get value | Cannot get value for iterator: Either the iterator belongs to a null value or it is an iterator to a primitive type (number, boolean, or string), but the iterator is different to @ref begin(). + +@liveexample{The following code shows how an `invalid_iterator` exception can be +caught.,invalid_iterator} + +@sa @ref exception for the base class of the library exceptions +@sa @ref parse_error for exceptions indicating a parse error +@sa @ref type_error for exceptions indicating executing a member function with + a wrong type +@sa @ref out_of_range for exceptions indicating access out of the defined range +@sa @ref other_error for exceptions indicating other library errors + +@since version 3.0.0 +*/ +class invalid_iterator : public exception +{ + public: + static invalid_iterator create(int id_, const std::string& what_arg) + { + std::string w = exception::name("invalid_iterator", id_) + what_arg; + return invalid_iterator(id_, w.c_str()); + } + + private: + invalid_iterator(int id_, const char* what_arg) + : exception(id_, what_arg) {} +}; + +/*! +@brief exception indicating executing a member function with a wrong type + +This exception is thrown in case of a type error; that is, a library function is +executed on a JSON value whose type does not match the expected semantics. + +Exceptions have ids 3xx. + +name / id | example message | description +----------------------------- | --------------- | ------------------------- +json.exception.type_error.301 | cannot create object from initializer list | To create an object from an initializer list, the initializer list must consist only of a list of pairs whose first element is a string. When this constraint is violated, an array is created instead. +json.exception.type_error.302 | type must be object, but is array | During implicit or explicit value conversion, the JSON type must be compatible to the target type. For instance, a JSON string can only be converted into string types, but not into numbers or boolean types. +json.exception.type_error.303 | incompatible ReferenceType for get_ref, actual type is object | To retrieve a reference to a value stored in a @ref basic_json object with @ref get_ref, the type of the reference must match the value type. For instance, for a JSON array, the @a ReferenceType must be @ref array_t&. +json.exception.type_error.304 | cannot use at() with string | The @ref at() member functions can only be executed for certain JSON types. +json.exception.type_error.305 | cannot use operator[] with string | The @ref operator[] member functions can only be executed for certain JSON types. +json.exception.type_error.306 | cannot use value() with string | The @ref value() member functions can only be executed for certain JSON types. +json.exception.type_error.307 | cannot use erase() with string | The @ref erase() member functions can only be executed for certain JSON types. +json.exception.type_error.308 | cannot use push_back() with string | The @ref push_back() and @ref operator+= member functions can only be executed for certain JSON types. +json.exception.type_error.309 | cannot use insert() with | The @ref insert() member functions can only be executed for certain JSON types. +json.exception.type_error.310 | cannot use swap() with number | The @ref swap() member functions can only be executed for certain JSON types. +json.exception.type_error.311 | cannot use emplace_back() with string | The @ref emplace_back() member function can only be executed for certain JSON types. +json.exception.type_error.312 | cannot use update() with string | The @ref update() member functions can only be executed for certain JSON types. +json.exception.type_error.313 | invalid value to unflatten | The @ref unflatten function converts an object whose keys are JSON Pointers back into an arbitrary nested JSON value. The JSON Pointers must not overlap, because then the resulting value would not be well defined. +json.exception.type_error.314 | only objects can be unflattened | The @ref unflatten function only works for an object whose keys are JSON Pointers. +json.exception.type_error.315 | values in object must be primitive | The @ref unflatten function only works for an object whose keys are JSON Pointers and whose values are primitive. +json.exception.type_error.316 | invalid UTF-8 byte at index 10: 0x7E | The @ref dump function only works with UTF-8 encoded strings; that is, if you assign a `std::string` to a JSON value, make sure it is UTF-8 encoded. | + +@liveexample{The following code shows how a `type_error` exception can be +caught.,type_error} + +@sa @ref exception for the base class of the library exceptions +@sa @ref parse_error for exceptions indicating a parse error +@sa @ref invalid_iterator for exceptions indicating errors with iterators +@sa @ref out_of_range for exceptions indicating access out of the defined range +@sa @ref other_error for exceptions indicating other library errors + +@since version 3.0.0 +*/ +class type_error : public exception +{ + public: + static type_error create(int id_, const std::string& what_arg) + { + std::string w = exception::name("type_error", id_) + what_arg; + return type_error(id_, w.c_str()); + } + + private: + type_error(int id_, const char* what_arg) : exception(id_, what_arg) {} +}; + +/*! +@brief exception indicating access out of the defined range + +This exception is thrown in case a library function is called on an input +parameter that exceeds the expected range, for instance in case of array +indices or nonexisting object keys. + +Exceptions have ids 4xx. + +name / id | example message | description +------------------------------- | --------------- | ------------------------- +json.exception.out_of_range.401 | array index 3 is out of range | The provided array index @a i is larger than @a size-1. +json.exception.out_of_range.402 | array index '-' (3) is out of range | The special array index `-` in a JSON Pointer never describes a valid element of the array, but the index past the end. That is, it can only be used to add elements at this position, but not to read it. +json.exception.out_of_range.403 | key 'foo' not found | The provided key was not found in the JSON object. +json.exception.out_of_range.404 | unresolved reference token 'foo' | A reference token in a JSON Pointer could not be resolved. +json.exception.out_of_range.405 | JSON pointer has no parent | The JSON Patch operations 'remove' and 'add' can not be applied to the root element of the JSON value. +json.exception.out_of_range.406 | number overflow parsing '10E1000' | A parsed number could not be stored as without changing it to NaN or INF. + +@liveexample{The following code shows how an `out_of_range` exception can be +caught.,out_of_range} + +@sa @ref exception for the base class of the library exceptions +@sa @ref parse_error for exceptions indicating a parse error +@sa @ref invalid_iterator for exceptions indicating errors with iterators +@sa @ref type_error for exceptions indicating executing a member function with + a wrong type +@sa @ref other_error for exceptions indicating other library errors + +@since version 3.0.0 +*/ +class out_of_range : public exception +{ + public: + static out_of_range create(int id_, const std::string& what_arg) + { + std::string w = exception::name("out_of_range", id_) + what_arg; + return out_of_range(id_, w.c_str()); + } + + private: + out_of_range(int id_, const char* what_arg) : exception(id_, what_arg) {} +}; + +/*! +@brief exception indicating other library errors + +This exception is thrown in case of errors that cannot be classified with the +other exception types. + +Exceptions have ids 5xx. + +name / id | example message | description +------------------------------ | --------------- | ------------------------- +json.exception.other_error.501 | unsuccessful: {"op":"test","path":"/baz", "value":"bar"} | A JSON Patch operation 'test' failed. The unsuccessful operation is also printed. + +@sa @ref exception for the base class of the library exceptions +@sa @ref parse_error for exceptions indicating a parse error +@sa @ref invalid_iterator for exceptions indicating errors with iterators +@sa @ref type_error for exceptions indicating executing a member function with + a wrong type +@sa @ref out_of_range for exceptions indicating access out of the defined range + +@liveexample{The following code shows how an `other_error` exception can be +caught.,other_error} + +@since version 3.0.0 +*/ +class other_error : public exception +{ + public: + static other_error create(int id_, const std::string& what_arg) + { + std::string w = exception::name("other_error", id_) + what_arg; + return other_error(id_, w.c_str()); + } + + private: + other_error(int id_, const char* what_arg) : exception(id_, what_arg) {} +}; + + + +/////////////////////////// +// JSON type enumeration // +/////////////////////////// + +/*! +@brief the JSON type enumeration + +This enumeration collects the different JSON types. It is internally used to +distinguish the stored values, and the functions @ref basic_json::is_null(), +@ref basic_json::is_object(), @ref basic_json::is_array(), +@ref basic_json::is_string(), @ref basic_json::is_boolean(), +@ref basic_json::is_number() (with @ref basic_json::is_number_integer(), +@ref basic_json::is_number_unsigned(), and @ref basic_json::is_number_float()), +@ref basic_json::is_discarded(), @ref basic_json::is_primitive(), and +@ref basic_json::is_structured() rely on it. + +@note There are three enumeration entries (number_integer, number_unsigned, and +number_float), because the library distinguishes these three types for numbers: +@ref basic_json::number_unsigned_t is used for unsigned integers, +@ref basic_json::number_integer_t is used for signed integers, and +@ref basic_json::number_float_t is used for floating-point numbers or to +approximate integers which do not fit in the limits of their respective type. + +@sa @ref basic_json::basic_json(const value_t value_type) -- create a JSON +value with the default value for a given type + @since version 1.0.0 */ -namespace +enum class value_t : uint8_t { + null, ///< null value + object, ///< object (unordered set of name/value pairs) + array, ///< array (ordered collection of values) + string, ///< string value + boolean, ///< boolean value + number_integer, ///< number value (signed integer) + number_unsigned, ///< number value (unsigned integer) + number_float, ///< number value (floating-point) + discarded ///< discarded by the the parser callback function +}; + +/*! +@brief comparison operator for JSON types + +Returns an ordering that is similar to Python: +- order: null < boolean < number < object < array < string +- furthermore, each type is not smaller than itself +- discarded values are not comparable + +@since version 1.0.0 +*/ +inline bool operator<(const value_t lhs, const value_t rhs) noexcept +{ + static constexpr std::array<uint8_t, 8> order = {{ + 0 /* null */, 3 /* object */, 4 /* array */, 5 /* string */, + 1 /* boolean */, 2 /* integer */, 2 /* unsigned */, 2 /* float */ + } + }; + + const auto l_index = static_cast<std::size_t>(lhs); + const auto r_index = static_cast<std::size_t>(rhs); + return l_index < order.size() and r_index < order.size() and order[l_index] < order[r_index]; +} + + +///////////// +// helpers // +///////////// + +template<typename> struct is_basic_json : std::false_type {}; + +NLOHMANN_BASIC_JSON_TPL_DECLARATION +struct is_basic_json<NLOHMANN_BASIC_JSON_TPL> : std::true_type {}; + +// alias templates to reduce boilerplate +template<bool B, typename T = void> +using enable_if_t = typename std::enable_if<B, T>::type; + +template<typename T> +using uncvref_t = typename std::remove_cv<typename std::remove_reference<T>::type>::type; + +// implementation of C++14 index_sequence and affiliates +// source: https://stackoverflow.com/a/32223343 +template<std::size_t... Ints> +struct index_sequence +{ + using type = index_sequence; + using value_type = std::size_t; + static constexpr std::size_t size() noexcept + { + return sizeof...(Ints); + } +}; + +template<class Sequence1, class Sequence2> +struct merge_and_renumber; + +template<std::size_t... I1, std::size_t... I2> +struct merge_and_renumber<index_sequence<I1...>, index_sequence<I2...>> + : index_sequence < I1..., (sizeof...(I1) + I2)... > {}; + +template<std::size_t N> +struct make_index_sequence + : merge_and_renumber < typename make_index_sequence < N / 2 >::type, + typename make_index_sequence < N - N / 2 >::type > {}; + +template<> struct make_index_sequence<0> : index_sequence<> {}; +template<> struct make_index_sequence<1> : index_sequence<0> {}; + +template<typename... Ts> +using index_sequence_for = make_index_sequence<sizeof...(Ts)>; + +/* +Implementation of two C++17 constructs: conjunction, negation. This is needed +to avoid evaluating all the traits in a condition + +For example: not std::is_same<void, T>::value and has_value_type<T>::value +will not compile when T = void (on MSVC at least). Whereas +conjunction<negation<std::is_same<void, T>>, has_value_type<T>>::value will +stop evaluating if negation<...>::value == false + +Please note that those constructs must be used with caution, since symbols can +become very long quickly (which can slow down compilation and cause MSVC +internal compiler errors). Only use it when you have to (see example ahead). +*/ +template<class...> struct conjunction : std::true_type {}; +template<class B1> struct conjunction<B1> : B1 {}; +template<class B1, class... Bn> +struct conjunction<B1, Bn...> : std::conditional<bool(B1::value), conjunction<Bn...>, B1>::type {}; + +template<class B> struct negation : std::integral_constant<bool, not B::value> {}; + +// dispatch utility (taken from ranges-v3) +template<unsigned N> struct priority_tag : priority_tag < N - 1 > {}; +template<> struct priority_tag<0> {}; + + +////////////////// +// constructors // +////////////////// + +template<value_t> struct external_constructor; + +template<> +struct external_constructor<value_t::boolean> +{ + template<typename BasicJsonType> + static void construct(BasicJsonType& j, typename BasicJsonType::boolean_t b) noexcept + { + j.m_type = value_t::boolean; + j.m_value = b; + j.assert_invariant(); + } +}; + +template<> +struct external_constructor<value_t::string> +{ + template<typename BasicJsonType> + static void construct(BasicJsonType& j, const typename BasicJsonType::string_t& s) + { + j.m_type = value_t::string; + j.m_value = s; + j.assert_invariant(); + } + + template<typename BasicJsonType> + static void construct(BasicJsonType& j, typename BasicJsonType::string_t&& s) + { + j.m_type = value_t::string; + j.m_value = std::move(s); + j.assert_invariant(); + } +}; + +template<> +struct external_constructor<value_t::number_float> +{ + template<typename BasicJsonType> + static void construct(BasicJsonType& j, typename BasicJsonType::number_float_t val) noexcept + { + j.m_type = value_t::number_float; + j.m_value = val; + j.assert_invariant(); + } +}; + +template<> +struct external_constructor<value_t::number_unsigned> +{ + template<typename BasicJsonType> + static void construct(BasicJsonType& j, typename BasicJsonType::number_unsigned_t val) noexcept + { + j.m_type = value_t::number_unsigned; + j.m_value = val; + j.assert_invariant(); + } +}; + +template<> +struct external_constructor<value_t::number_integer> +{ + template<typename BasicJsonType> + static void construct(BasicJsonType& j, typename BasicJsonType::number_integer_t val) noexcept + { + j.m_type = value_t::number_integer; + j.m_value = val; + j.assert_invariant(); + } +}; + +template<> +struct external_constructor<value_t::array> +{ + template<typename BasicJsonType> + static void construct(BasicJsonType& j, const typename BasicJsonType::array_t& arr) + { + j.m_type = value_t::array; + j.m_value = arr; + j.assert_invariant(); + } + + template<typename BasicJsonType> + static void construct(BasicJsonType& j, typename BasicJsonType::array_t&& arr) + { + j.m_type = value_t::array; + j.m_value = std::move(arr); + j.assert_invariant(); + } + + template<typename BasicJsonType, typename CompatibleArrayType, + enable_if_t<not std::is_same<CompatibleArrayType, typename BasicJsonType::array_t>::value, + int> = 0> + static void construct(BasicJsonType& j, const CompatibleArrayType& arr) + { + using std::begin; + using std::end; + j.m_type = value_t::array; + j.m_value.array = j.template create<typename BasicJsonType::array_t>(begin(arr), end(arr)); + j.assert_invariant(); + } + + template<typename BasicJsonType> + static void construct(BasicJsonType& j, const std::vector<bool>& arr) + { + j.m_type = value_t::array; + j.m_value = value_t::array; + j.m_value.array->reserve(arr.size()); + for (const bool x : arr) + { + j.m_value.array->push_back(x); + } + j.assert_invariant(); + } + + template<typename BasicJsonType, typename T, + enable_if_t<std::is_convertible<T, BasicJsonType>::value, int> = 0> + static void construct(BasicJsonType& j, const std::valarray<T>& arr) + { + j.m_type = value_t::array; + j.m_value = value_t::array; + j.m_value.array->resize(arr.size()); + std::copy(std::begin(arr), std::end(arr), j.m_value.array->begin()); + j.assert_invariant(); + } +}; + +template<> +struct external_constructor<value_t::object> +{ + template<typename BasicJsonType> + static void construct(BasicJsonType& j, const typename BasicJsonType::object_t& obj) + { + j.m_type = value_t::object; + j.m_value = obj; + j.assert_invariant(); + } + + template<typename BasicJsonType> + static void construct(BasicJsonType& j, typename BasicJsonType::object_t&& obj) + { + j.m_type = value_t::object; + j.m_value = std::move(obj); + j.assert_invariant(); + } + + template<typename BasicJsonType, typename CompatibleObjectType, + enable_if_t<not std::is_same<CompatibleObjectType, typename BasicJsonType::object_t>::value, int> = 0> + static void construct(BasicJsonType& j, const CompatibleObjectType& obj) + { + using std::begin; + using std::end; + + j.m_type = value_t::object; + j.m_value.object = j.template create<typename BasicJsonType::object_t>(begin(obj), end(obj)); + j.assert_invariant(); + } +}; + + +//////////////////////// +// has_/is_ functions // +//////////////////////// + /*! @brief Helper to determine whether there's a key_type for T. + +This helper is used to tell associative containers apart from other containers +such as sequence containers. For instance, `std::map` passes the test as it +contains a `mapped_type`, whereas `std::vector` fails the test. + @sa http://stackoverflow.com/a/7728728/266378 +@since version 1.0.0, overworked in version 2.0.6 */ +#define NLOHMANN_JSON_HAS_HELPER(type) \ + template<typename T> struct has_##type { \ + private: \ + template<typename U, typename = typename U::type> \ + static int detect(U &&); \ + static void detect(...); \ + public: \ + static constexpr bool value = \ + std::is_integral<decltype(detect(std::declval<T>()))>::value; \ + } + +NLOHMANN_JSON_HAS_HELPER(mapped_type); +NLOHMANN_JSON_HAS_HELPER(key_type); +NLOHMANN_JSON_HAS_HELPER(value_type); +NLOHMANN_JSON_HAS_HELPER(iterator); + +#undef NLOHMANN_JSON_HAS_HELPER + + +template<bool B, class RealType, class CompatibleObjectType> +struct is_compatible_object_type_impl : std::false_type {}; + +template<class RealType, class CompatibleObjectType> +struct is_compatible_object_type_impl<true, RealType, CompatibleObjectType> +{ + static constexpr auto value = + std::is_constructible<typename RealType::key_type, typename CompatibleObjectType::key_type>::value and + std::is_constructible<typename RealType::mapped_type, typename CompatibleObjectType::mapped_type>::value; +}; + +template<class BasicJsonType, class CompatibleObjectType> +struct is_compatible_object_type +{ + static auto constexpr value = is_compatible_object_type_impl < + conjunction<negation<std::is_same<void, CompatibleObjectType>>, + has_mapped_type<CompatibleObjectType>, + has_key_type<CompatibleObjectType>>::value, + typename BasicJsonType::object_t, CompatibleObjectType >::value; +}; + +template<typename BasicJsonType, typename T> +struct is_basic_json_nested_type +{ + static auto constexpr value = std::is_same<T, typename BasicJsonType::iterator>::value or + std::is_same<T, typename BasicJsonType::const_iterator>::value or + std::is_same<T, typename BasicJsonType::reverse_iterator>::value or + std::is_same<T, typename BasicJsonType::const_reverse_iterator>::value; +}; + +template<class BasicJsonType, class CompatibleArrayType> +struct is_compatible_array_type +{ + static auto constexpr value = + conjunction<negation<std::is_same<void, CompatibleArrayType>>, + negation<is_compatible_object_type< + BasicJsonType, CompatibleArrayType>>, + negation<std::is_constructible<typename BasicJsonType::string_t, + CompatibleArrayType>>, + negation<is_basic_json_nested_type<BasicJsonType, CompatibleArrayType>>, + has_value_type<CompatibleArrayType>, + has_iterator<CompatibleArrayType>>::value; +}; + +template<bool, typename, typename> +struct is_compatible_integer_type_impl : std::false_type {}; + +template<typename RealIntegerType, typename CompatibleNumberIntegerType> +struct is_compatible_integer_type_impl<true, RealIntegerType, CompatibleNumberIntegerType> +{ + // is there an assert somewhere on overflows? + using RealLimits = std::numeric_limits<RealIntegerType>; + using CompatibleLimits = std::numeric_limits<CompatibleNumberIntegerType>; + + static constexpr auto value = + std::is_constructible<RealIntegerType, CompatibleNumberIntegerType>::value and + CompatibleLimits::is_integer and + RealLimits::is_signed == CompatibleLimits::is_signed; +}; + +template<typename RealIntegerType, typename CompatibleNumberIntegerType> +struct is_compatible_integer_type +{ + static constexpr auto value = + is_compatible_integer_type_impl < + std::is_integral<CompatibleNumberIntegerType>::value and + not std::is_same<bool, CompatibleNumberIntegerType>::value, + RealIntegerType, CompatibleNumberIntegerType >::value; +}; + + +// trait checking if JSONSerializer<T>::from_json(json const&, udt&) exists +template<typename BasicJsonType, typename T> +struct has_from_json +{ + private: + // also check the return type of from_json + template<typename U, typename = enable_if_t<std::is_same<void, decltype(uncvref_t<U>::from_json( + std::declval<BasicJsonType>(), std::declval<T&>()))>::value>> + static int detect(U&&); + static void detect(...); + + public: + static constexpr bool value = std::is_integral<decltype( + detect(std::declval<typename BasicJsonType::template json_serializer<T, void>>()))>::value; +}; + +// This trait checks if JSONSerializer<T>::from_json(json const&) exists +// this overload is used for non-default-constructible user-defined-types +template<typename BasicJsonType, typename T> +struct has_non_default_from_json +{ + private: + template<typename U, typename = + enable_if_t<std::is_same<T, decltype(uncvref_t<U>::from_json(std::declval<BasicJsonType>()))>::value>> + static int detect(U&&); + static void detect(...); + + public: + static constexpr bool value = std::is_integral<decltype(detect( + std::declval<typename BasicJsonType::template json_serializer<T, void>>()))>::value; +}; + +// This trait checks if BasicJsonType::json_serializer<T>::to_json exists +template<typename BasicJsonType, typename T> +struct has_to_json +{ + private: + template<typename U, typename = decltype(uncvref_t<U>::to_json( + std::declval<BasicJsonType&>(), std::declval<T>()))> + static int detect(U&&); + static void detect(...); + + public: + static constexpr bool value = std::is_integral<decltype(detect( + std::declval<typename BasicJsonType::template json_serializer<T, void>>()))>::value; +}; + + +///////////// +// to_json // +///////////// + +template<typename BasicJsonType, typename T, + enable_if_t<std::is_same<T, typename BasicJsonType::boolean_t>::value, int> = 0> +void to_json(BasicJsonType& j, T b) noexcept +{ + external_constructor<value_t::boolean>::construct(j, b); +} + +template<typename BasicJsonType, typename CompatibleString, + enable_if_t<std::is_constructible<typename BasicJsonType::string_t, CompatibleString>::value, int> = 0> +void to_json(BasicJsonType& j, const CompatibleString& s) +{ + external_constructor<value_t::string>::construct(j, s); +} + +template<typename BasicJsonType> +void to_json(BasicJsonType& j, typename BasicJsonType::string_t&& s) +{ + external_constructor<value_t::string>::construct(j, std::move(s)); +} + +template<typename BasicJsonType, typename FloatType, + enable_if_t<std::is_floating_point<FloatType>::value, int> = 0> +void to_json(BasicJsonType& j, FloatType val) noexcept +{ + external_constructor<value_t::number_float>::construct(j, static_cast<typename BasicJsonType::number_float_t>(val)); +} + +template<typename BasicJsonType, typename CompatibleNumberUnsignedType, + enable_if_t<is_compatible_integer_type<typename BasicJsonType::number_unsigned_t, CompatibleNumberUnsignedType>::value, int> = 0> +void to_json(BasicJsonType& j, CompatibleNumberUnsignedType val) noexcept +{ + external_constructor<value_t::number_unsigned>::construct(j, static_cast<typename BasicJsonType::number_unsigned_t>(val)); +} + +template<typename BasicJsonType, typename CompatibleNumberIntegerType, + enable_if_t<is_compatible_integer_type<typename BasicJsonType::number_integer_t, CompatibleNumberIntegerType>::value, int> = 0> +void to_json(BasicJsonType& j, CompatibleNumberIntegerType val) noexcept +{ + external_constructor<value_t::number_integer>::construct(j, static_cast<typename BasicJsonType::number_integer_t>(val)); +} + +template<typename BasicJsonType, typename EnumType, + enable_if_t<std::is_enum<EnumType>::value, int> = 0> +void to_json(BasicJsonType& j, EnumType e) noexcept +{ + using underlying_type = typename std::underlying_type<EnumType>::type; + external_constructor<value_t::number_integer>::construct(j, static_cast<underlying_type>(e)); +} + +template<typename BasicJsonType> +void to_json(BasicJsonType& j, const std::vector<bool>& e) +{ + external_constructor<value_t::array>::construct(j, e); +} + +template<typename BasicJsonType, typename CompatibleArrayType, + enable_if_t<is_compatible_array_type<BasicJsonType, CompatibleArrayType>::value or + std::is_same<typename BasicJsonType::array_t, CompatibleArrayType>::value, + int> = 0> +void to_json(BasicJsonType& j, const CompatibleArrayType& arr) +{ + external_constructor<value_t::array>::construct(j, arr); +} + +template<typename BasicJsonType, typename T, + enable_if_t<std::is_convertible<T, BasicJsonType>::value, int> = 0> +void to_json(BasicJsonType& j, std::valarray<T> arr) +{ + external_constructor<value_t::array>::construct(j, std::move(arr)); +} + +template<typename BasicJsonType> +void to_json(BasicJsonType& j, typename BasicJsonType::array_t&& arr) +{ + external_constructor<value_t::array>::construct(j, std::move(arr)); +} + +template<typename BasicJsonType, typename CompatibleObjectType, + enable_if_t<is_compatible_object_type<BasicJsonType, CompatibleObjectType>::value, int> = 0> +void to_json(BasicJsonType& j, const CompatibleObjectType& obj) +{ + external_constructor<value_t::object>::construct(j, obj); +} + +template<typename BasicJsonType> +void to_json(BasicJsonType& j, typename BasicJsonType::object_t&& obj) +{ + external_constructor<value_t::object>::construct(j, std::move(obj)); +} + +template<typename BasicJsonType, typename T, std::size_t N, + enable_if_t<not std::is_constructible<typename BasicJsonType::string_t, T (&)[N]>::value, int> = 0> +void to_json(BasicJsonType& j, T (&arr)[N]) +{ + external_constructor<value_t::array>::construct(j, arr); +} + +template<typename BasicJsonType, typename... Args> +void to_json(BasicJsonType& j, const std::pair<Args...>& p) +{ + j = {p.first, p.second}; +} + +template<typename BasicJsonType, typename Tuple, std::size_t... Idx> +void to_json_tuple_impl(BasicJsonType& j, const Tuple& t, index_sequence<Idx...>) +{ + j = {std::get<Idx>(t)...}; +} + +template<typename BasicJsonType, typename... Args> +void to_json(BasicJsonType& j, const std::tuple<Args...>& t) +{ + to_json_tuple_impl(j, t, index_sequence_for<Args...> {}); +} + +/////////////// +// from_json // +/////////////// + +// overloads for basic_json template parameters +template<typename BasicJsonType, typename ArithmeticType, + enable_if_t<std::is_arithmetic<ArithmeticType>::value and + not std::is_same<ArithmeticType, typename BasicJsonType::boolean_t>::value, + int> = 0> +void get_arithmetic_value(const BasicJsonType& j, ArithmeticType& val) +{ + switch (static_cast<value_t>(j)) + { + case value_t::number_unsigned: + { + val = static_cast<ArithmeticType>(*j.template get_ptr<const typename BasicJsonType::number_unsigned_t*>()); + break; + } + case value_t::number_integer: + { + val = static_cast<ArithmeticType>(*j.template get_ptr<const typename BasicJsonType::number_integer_t*>()); + break; + } + case value_t::number_float: + { + val = static_cast<ArithmeticType>(*j.template get_ptr<const typename BasicJsonType::number_float_t*>()); + break; + } + + default: + JSON_THROW(type_error::create(302, "type must be number, but is " + std::string(j.type_name()))); + } +} + +template<typename BasicJsonType> +void from_json(const BasicJsonType& j, typename BasicJsonType::boolean_t& b) +{ + if (JSON_UNLIKELY(not j.is_boolean())) + { + JSON_THROW(type_error::create(302, "type must be boolean, but is " + std::string(j.type_name()))); + } + b = *j.template get_ptr<const typename BasicJsonType::boolean_t*>(); +} + +template<typename BasicJsonType> +void from_json(const BasicJsonType& j, typename BasicJsonType::string_t& s) +{ + if (JSON_UNLIKELY(not j.is_string())) + { + JSON_THROW(type_error::create(302, "type must be string, but is " + std::string(j.type_name()))); + } + s = *j.template get_ptr<const typename BasicJsonType::string_t*>(); +} + +template<typename BasicJsonType> +void from_json(const BasicJsonType& j, typename BasicJsonType::number_float_t& val) +{ + get_arithmetic_value(j, val); +} + +template<typename BasicJsonType> +void from_json(const BasicJsonType& j, typename BasicJsonType::number_unsigned_t& val) +{ + get_arithmetic_value(j, val); +} + +template<typename BasicJsonType> +void from_json(const BasicJsonType& j, typename BasicJsonType::number_integer_t& val) +{ + get_arithmetic_value(j, val); +} + +template<typename BasicJsonType, typename EnumType, + enable_if_t<std::is_enum<EnumType>::value, int> = 0> +void from_json(const BasicJsonType& j, EnumType& e) +{ + typename std::underlying_type<EnumType>::type val; + get_arithmetic_value(j, val); + e = static_cast<EnumType>(val); +} + +template<typename BasicJsonType> +void from_json(const BasicJsonType& j, typename BasicJsonType::array_t& arr) +{ + if (JSON_UNLIKELY(not j.is_array())) + { + JSON_THROW(type_error::create(302, "type must be array, but is " + std::string(j.type_name()))); + } + arr = *j.template get_ptr<const typename BasicJsonType::array_t*>(); +} + +// forward_list doesn't have an insert method +template<typename BasicJsonType, typename T, typename Allocator, + enable_if_t<std::is_convertible<BasicJsonType, T>::value, int> = 0> +void from_json(const BasicJsonType& j, std::forward_list<T, Allocator>& l) +{ + if (JSON_UNLIKELY(not j.is_array())) + { + JSON_THROW(type_error::create(302, "type must be array, but is " + std::string(j.type_name()))); + } + std::transform(j.rbegin(), j.rend(), + std::front_inserter(l), [](const BasicJsonType & i) + { + return i.template get<T>(); + }); +} + +// valarray doesn't have an insert method +template<typename BasicJsonType, typename T, + enable_if_t<std::is_convertible<BasicJsonType, T>::value, int> = 0> +void from_json(const BasicJsonType& j, std::valarray<T>& l) +{ + if (JSON_UNLIKELY(not j.is_array())) + { + JSON_THROW(type_error::create(302, "type must be array, but is " + std::string(j.type_name()))); + } + l.resize(j.size()); + std::copy(j.m_value.array->begin(), j.m_value.array->end(), std::begin(l)); +} + +template<typename BasicJsonType, typename CompatibleArrayType> +void from_json_array_impl(const BasicJsonType& j, CompatibleArrayType& arr, priority_tag<0> /*unused*/) +{ + using std::end; + + std::transform(j.begin(), j.end(), + std::inserter(arr, end(arr)), [](const BasicJsonType & i) + { + // get<BasicJsonType>() returns *this, this won't call a from_json + // method when value_type is BasicJsonType + return i.template get<typename CompatibleArrayType::value_type>(); + }); +} + +template<typename BasicJsonType, typename CompatibleArrayType> +auto from_json_array_impl(const BasicJsonType& j, CompatibleArrayType& arr, priority_tag<1> /*unused*/) +-> decltype( + arr.reserve(std::declval<typename CompatibleArrayType::size_type>()), + void()) +{ + using std::end; + + arr.reserve(j.size()); + std::transform(j.begin(), j.end(), + std::inserter(arr, end(arr)), [](const BasicJsonType & i) + { + // get<BasicJsonType>() returns *this, this won't call a from_json + // method when value_type is BasicJsonType + return i.template get<typename CompatibleArrayType::value_type>(); + }); +} + +template<typename BasicJsonType, typename T, std::size_t N> +void from_json_array_impl(const BasicJsonType& j, std::array<T, N>& arr, priority_tag<2> /*unused*/) +{ + for (std::size_t i = 0; i < N; ++i) + { + arr[i] = j.at(i).template get<T>(); + } +} + +template<typename BasicJsonType, typename CompatibleArrayType, + enable_if_t<is_compatible_array_type<BasicJsonType, CompatibleArrayType>::value and + std::is_convertible<BasicJsonType, typename CompatibleArrayType::value_type>::value and + not std::is_same<typename BasicJsonType::array_t, CompatibleArrayType>::value, int> = 0> +void from_json(const BasicJsonType& j, CompatibleArrayType& arr) +{ + if (JSON_UNLIKELY(not j.is_array())) + { + JSON_THROW(type_error::create(302, "type must be array, but is " + std::string(j.type_name()))); + } + + from_json_array_impl(j, arr, priority_tag<2> {}); +} + +template<typename BasicJsonType, typename CompatibleObjectType, + enable_if_t<is_compatible_object_type<BasicJsonType, CompatibleObjectType>::value, int> = 0> +void from_json(const BasicJsonType& j, CompatibleObjectType& obj) +{ + if (JSON_UNLIKELY(not j.is_object())) + { + JSON_THROW(type_error::create(302, "type must be object, but is " + std::string(j.type_name()))); + } + + auto inner_object = j.template get_ptr<const typename BasicJsonType::object_t*>(); + using value_type = typename CompatibleObjectType::value_type; + std::transform( + inner_object->begin(), inner_object->end(), + std::inserter(obj, obj.begin()), + [](typename BasicJsonType::object_t::value_type const & p) + { + return value_type(p.first, p.second.template get<typename CompatibleObjectType::mapped_type>()); + }); +} + +// overload for arithmetic types, not chosen for basic_json template arguments +// (BooleanType, etc..); note: Is it really necessary to provide explicit +// overloads for boolean_t etc. in case of a custom BooleanType which is not +// an arithmetic type? +template<typename BasicJsonType, typename ArithmeticType, + enable_if_t < + std::is_arithmetic<ArithmeticType>::value and + not std::is_same<ArithmeticType, typename BasicJsonType::number_unsigned_t>::value and + not std::is_same<ArithmeticType, typename BasicJsonType::number_integer_t>::value and + not std::is_same<ArithmeticType, typename BasicJsonType::number_float_t>::value and + not std::is_same<ArithmeticType, typename BasicJsonType::boolean_t>::value, + int> = 0> +void from_json(const BasicJsonType& j, ArithmeticType& val) +{ + switch (static_cast<value_t>(j)) + { + case value_t::number_unsigned: + { + val = static_cast<ArithmeticType>(*j.template get_ptr<const typename BasicJsonType::number_unsigned_t*>()); + break; + } + case value_t::number_integer: + { + val = static_cast<ArithmeticType>(*j.template get_ptr<const typename BasicJsonType::number_integer_t*>()); + break; + } + case value_t::number_float: + { + val = static_cast<ArithmeticType>(*j.template get_ptr<const typename BasicJsonType::number_float_t*>()); + break; + } + case value_t::boolean: + { + val = static_cast<ArithmeticType>(*j.template get_ptr<const typename BasicJsonType::boolean_t*>()); + break; + } + + default: + JSON_THROW(type_error::create(302, "type must be number, but is " + std::string(j.type_name()))); + } +} + +template<typename BasicJsonType, typename A1, typename A2> +void from_json(const BasicJsonType& j, std::pair<A1, A2>& p) +{ + p = {j.at(0).template get<A1>(), j.at(1).template get<A2>()}; +} + +template<typename BasicJsonType, typename Tuple, std::size_t... Idx> +void from_json_tuple_impl(const BasicJsonType& j, Tuple& t, index_sequence<Idx...>) +{ + t = std::make_tuple(j.at(Idx).template get<typename std::tuple_element<Idx, Tuple>::type>()...); +} + +template<typename BasicJsonType, typename... Args> +void from_json(const BasicJsonType& j, std::tuple<Args...>& t) +{ + from_json_tuple_impl(j, t, index_sequence_for<Args...> {}); +} + +struct to_json_fn +{ + private: + template<typename BasicJsonType, typename T> + auto call(BasicJsonType& j, T&& val, priority_tag<1> /*unused*/) const noexcept(noexcept(to_json(j, std::forward<T>(val)))) + -> decltype(to_json(j, std::forward<T>(val)), void()) + { + return to_json(j, std::forward<T>(val)); + } + + template<typename BasicJsonType, typename T> + void call(BasicJsonType& /*unused*/, T&& /*unused*/, priority_tag<0> /*unused*/) const noexcept + { + static_assert(sizeof(BasicJsonType) == 0, + "could not find to_json() method in T's namespace"); + +#ifdef _MSC_VER + // MSVC does not show a stacktrace for the above assert + using decayed = uncvref_t<T>; + static_assert(sizeof(typename decayed::force_msvc_stacktrace) == 0, + "forcing MSVC stacktrace to show which T we're talking about."); +#endif + } + + public: + template<typename BasicJsonType, typename T> + void operator()(BasicJsonType& j, T&& val) const + noexcept(noexcept(std::declval<to_json_fn>().call(j, std::forward<T>(val), priority_tag<1> {}))) + { + return call(j, std::forward<T>(val), priority_tag<1> {}); + } +}; + +struct from_json_fn +{ + private: + template<typename BasicJsonType, typename T> + auto call(const BasicJsonType& j, T& val, priority_tag<1> /*unused*/) const + noexcept(noexcept(from_json(j, val))) + -> decltype(from_json(j, val), void()) + { + return from_json(j, val); + } + + template<typename BasicJsonType, typename T> + void call(const BasicJsonType& /*unused*/, T& /*unused*/, priority_tag<0> /*unused*/) const noexcept + { + static_assert(sizeof(BasicJsonType) == 0, + "could not find from_json() method in T's namespace"); +#ifdef _MSC_VER + // MSVC does not show a stacktrace for the above assert + using decayed = uncvref_t<T>; + static_assert(sizeof(typename decayed::force_msvc_stacktrace) == 0, + "forcing MSVC stacktrace to show which T we're talking about."); +#endif + } + + public: + template<typename BasicJsonType, typename T> + void operator()(const BasicJsonType& j, T& val) const + noexcept(noexcept(std::declval<from_json_fn>().call(j, val, priority_tag<1> {}))) + { + return call(j, val, priority_tag<1> {}); + } +}; + +// taken from ranges-v3 +template<typename T> +struct static_const +{ + static constexpr T value{}; +}; + template<typename T> -struct has_mapped_type +constexpr T static_const<T>::value; + +//////////////////// +// input adapters // +//////////////////// + +/*! +@brief abstract input adapter interface + +Produces a stream of std::char_traits<char>::int_type characters from a +std::istream, a buffer, or some other input type. Accepts the return of exactly +one non-EOF character for future input. The int_type characters returned +consist of all valid char values as positive values (typically unsigned char), +plus an EOF value outside that range, specified by the value of the function +std::char_traits<char>::eof(). This value is typically -1, but could be any +arbitrary value which is not a valid char value. +*/ +struct input_adapter_protocol +{ + /// get a character [0,255] or std::char_traits<char>::eof(). + virtual std::char_traits<char>::int_type get_character() = 0; + /// restore the last non-eof() character to input + virtual void unget_character() = 0; + virtual ~input_adapter_protocol() = default; +}; + +/// a type to simplify interfaces +using input_adapter_t = std::shared_ptr<input_adapter_protocol>; + +/*! +Input adapter for a (caching) istream. Ignores a UFT Byte Order Mark at +beginning of input. Does not support changing the underlying std::streambuf +in mid-input. Maintains underlying std::istream and std::streambuf to support +subsequent use of standard std::istream operations to process any input +characters following those used in parsing the JSON input. Clears the +std::istream flags; any input errors (e.g., EOF) will be detected by the first +subsequent call for input from the std::istream. +*/ +class input_stream_adapter : public input_adapter_protocol +{ + public: + ~input_stream_adapter() override + { + // clear stream flags; we use underlying streambuf I/O, do not + // maintain ifstream flags + is.clear(); + } + + explicit input_stream_adapter(std::istream& i) + : is(i), sb(*i.rdbuf()) + { + // skip byte order mark + std::char_traits<char>::int_type c; + if ((c = get_character()) == 0xEF) + { + if ((c = get_character()) == 0xBB) + { + if ((c = get_character()) == 0xBF) + { + return; // Ignore BOM + } + else if (c != std::char_traits<char>::eof()) + { + is.unget(); + } + is.putback('\xBB'); + } + else if (c != std::char_traits<char>::eof()) + { + is.unget(); + } + is.putback('\xEF'); + } + else if (c != std::char_traits<char>::eof()) + { + is.unget(); // no byte order mark; process as usual + } + } + + // delete because of pointer members + input_stream_adapter(const input_stream_adapter&) = delete; + input_stream_adapter& operator=(input_stream_adapter&) = delete; + + // std::istream/std::streambuf use std::char_traits<char>::to_int_type, to + // ensure that std::char_traits<char>::eof() and the character 0xFF do not + // end up as the same value, eg. 0xFFFFFFFF. + std::char_traits<char>::int_type get_character() override + { + return sb.sbumpc(); + } + + void unget_character() override + { + sb.sungetc(); // is.unget() avoided for performance + } + + private: + /// the associated input stream + std::istream& is; + std::streambuf& sb; +}; + +/// input adapter for buffer input +class input_buffer_adapter : public input_adapter_protocol { + public: + input_buffer_adapter(const char* b, const std::size_t l) + : cursor(b), limit(b + l), start(b) + { + // skip byte order mark + if (l >= 3 and b[0] == '\xEF' and b[1] == '\xBB' and b[2] == '\xBF') + { + cursor += 3; + } + } + + // delete because of pointer members + input_buffer_adapter(const input_buffer_adapter&) = delete; + input_buffer_adapter& operator=(input_buffer_adapter&) = delete; + + std::char_traits<char>::int_type get_character() noexcept override + { + if (JSON_LIKELY(cursor < limit)) + { + return std::char_traits<char>::to_int_type(*(cursor++)); + } + + return std::char_traits<char>::eof(); + } + + void unget_character() noexcept override + { + if (JSON_LIKELY(cursor > start)) + { + --cursor; + } + } + private: - template<typename C> static char test(typename C::mapped_type*); - template<typename C> static char (&test(...))[2]; + /// pointer to the current character + const char* cursor; + /// pointer past the last character + const char* limit; + /// pointer to the first character + const char* start; +}; + +class input_adapter +{ public: - static constexpr bool value = sizeof(test<T>(0)) == 1; + // native support + + /// input adapter for input stream + input_adapter(std::istream& i) + : ia(std::make_shared<input_stream_adapter>(i)) {} + + /// input adapter for input stream + input_adapter(std::istream&& i) + : ia(std::make_shared<input_stream_adapter>(i)) {} + + /// input adapter for buffer + template<typename CharT, + typename std::enable_if< + std::is_pointer<CharT>::value and + std::is_integral<typename std::remove_pointer<CharT>::type>::value and + sizeof(typename std::remove_pointer<CharT>::type) == 1, + int>::type = 0> + input_adapter(CharT b, std::size_t l) + : ia(std::make_shared<input_buffer_adapter>(reinterpret_cast<const char*>(b), l)) {} + + // derived support + + /// input adapter for string literal + template<typename CharT, + typename std::enable_if< + std::is_pointer<CharT>::value and + std::is_integral<typename std::remove_pointer<CharT>::type>::value and + sizeof(typename std::remove_pointer<CharT>::type) == 1, + int>::type = 0> + input_adapter(CharT b) + : input_adapter(reinterpret_cast<const char*>(b), + std::strlen(reinterpret_cast<const char*>(b))) {} + + /// input adapter for iterator range with contiguous storage + template<class IteratorType, + typename std::enable_if< + std::is_same<typename std::iterator_traits<IteratorType>::iterator_category, std::random_access_iterator_tag>::value, + int>::type = 0> + input_adapter(IteratorType first, IteratorType last) + { + // assertion to check that the iterator range is indeed contiguous, + // see http://stackoverflow.com/a/35008842/266378 for more discussion + assert(std::accumulate( + first, last, std::pair<bool, int>(true, 0), + [&first](std::pair<bool, int> res, decltype(*first) val) + { + res.first &= (val == *(std::next(std::addressof(*first), res.second++))); + return res; + }).first); + + // assertion to check that each element is 1 byte long + static_assert( + sizeof(typename std::iterator_traits<IteratorType>::value_type) == 1, + "each element in the iterator range must have the size of 1 byte"); + + const auto len = static_cast<size_t>(std::distance(first, last)); + if (JSON_LIKELY(len > 0)) + { + // there is at least one element: use the address of first + ia = std::make_shared<input_buffer_adapter>(reinterpret_cast<const char*>(&(*first)), len); + } + else + { + // the address of first cannot be used: use nullptr + ia = std::make_shared<input_buffer_adapter>(nullptr, len); + } + } + + /// input adapter for array + template<class T, std::size_t N> + input_adapter(T (&array)[N]) + : input_adapter(std::begin(array), std::end(array)) {} + + /// input adapter for contiguous container + template<class ContiguousContainer, typename + std::enable_if<not std::is_pointer<ContiguousContainer>::value and + std::is_base_of<std::random_access_iterator_tag, typename std::iterator_traits<decltype(std::begin(std::declval<ContiguousContainer const>()))>::iterator_category>::value, + int>::type = 0> + input_adapter(const ContiguousContainer& c) + : input_adapter(std::begin(c), std::end(c)) {} + + operator input_adapter_t() + { + return ia; + } + + private: + /// the actual adapter + input_adapter_t ia = nullptr; }; +////////////////////// +// lexer and parser // +////////////////////// + /*! -@brief helper class to create locales with decimal point -@sa https://github.com/nlohmann/json/issues/51#issuecomment-86869315 +@brief lexical analysis + +This class organizes the lexical analysis during JSON deserialization. */ -class DecimalSeparator : public std::numpunct<char> +template<typename BasicJsonType> +class lexer { - protected: - char do_decimal_point() const + using number_integer_t = typename BasicJsonType::number_integer_t; + using number_unsigned_t = typename BasicJsonType::number_unsigned_t; + using number_float_t = typename BasicJsonType::number_float_t; + + public: + /// token types for the parser + enum class token_type + { + uninitialized, ///< indicating the scanner is uninitialized + literal_true, ///< the `true` literal + literal_false, ///< the `false` literal + literal_null, ///< the `null` literal + value_string, ///< a string -- use get_string() for actual value + value_unsigned, ///< an unsigned integer -- use get_number_unsigned() for actual value + value_integer, ///< a signed integer -- use get_number_integer() for actual value + value_float, ///< an floating point number -- use get_number_float() for actual value + begin_array, ///< the character for array begin `[` + begin_object, ///< the character for object begin `{` + end_array, ///< the character for array end `]` + end_object, ///< the character for object end `}` + name_separator, ///< the name separator `:` + value_separator, ///< the value separator `,` + parse_error, ///< indicating a parse error + end_of_input, ///< indicating the end of the input buffer + literal_or_value ///< a literal or the begin of a value (only for diagnostics) + }; + + /// return name of values of type token_type (only used for errors) + static const char* token_type_name(const token_type t) noexcept + { + switch (t) + { + case token_type::uninitialized: + return "<uninitialized>"; + case token_type::literal_true: + return "true literal"; + case token_type::literal_false: + return "false literal"; + case token_type::literal_null: + return "null literal"; + case token_type::value_string: + return "string literal"; + case lexer::token_type::value_unsigned: + case lexer::token_type::value_integer: + case lexer::token_type::value_float: + return "number literal"; + case token_type::begin_array: + return "'['"; + case token_type::begin_object: + return "'{'"; + case token_type::end_array: + return "']'"; + case token_type::end_object: + return "'}'"; + case token_type::name_separator: + return "':'"; + case token_type::value_separator: + return "','"; + case token_type::parse_error: + return "<parse error>"; + case token_type::end_of_input: + return "end of input"; + case token_type::literal_or_value: + return "'[', '{', or a literal"; + default: // catch non-enum values + return "unknown token"; // LCOV_EXCL_LINE + } + } + + explicit lexer(detail::input_adapter_t adapter) + : ia(std::move(adapter)), decimal_point_char(get_decimal_point()) {} + + // delete because of pointer members + lexer(const lexer&) = delete; + lexer& operator=(lexer&) = delete; + + private: + ///////////////////// + // locales + ///////////////////// + + /// return the locale-dependent decimal point + static char get_decimal_point() noexcept + { + const auto loc = localeconv(); + assert(loc != nullptr); + return (loc->decimal_point == nullptr) ? '.' : *(loc->decimal_point); + } + + ///////////////////// + // scan functions + ///////////////////// + + /*! + @brief get codepoint from 4 hex characters following `\u` + + For input "\u c1 c2 c3 c4" the codepoint is: + (c1 * 0x1000) + (c2 * 0x0100) + (c3 * 0x0010) + c4 + = (c1 << 12) + (c2 << 8) + (c3 << 4) + (c4 << 0) + + Furthermore, the possible characters '0'..'9', 'A'..'F', and 'a'..'f' + must be converted to the integers 0x0..0x9, 0xA..0xF, 0xA..0xF, resp. The + conversion is done by subtracting the offset (0x30, 0x37, and 0x57) + between the ASCII value of the character and the desired integer value. + + @return codepoint (0x0000..0xFFFF) or -1 in case of an error (e.g. EOF or + non-hex character) + */ + int get_codepoint() + { + // this function only makes sense after reading `\u` + assert(current == 'u'); + int codepoint = 0; + + const auto factors = { 12, 8, 4, 0 }; + for (const auto factor : factors) + { + get(); + + if (current >= '0' and current <= '9') + { + codepoint += ((current - 0x30) << factor); + } + else if (current >= 'A' and current <= 'F') + { + codepoint += ((current - 0x37) << factor); + } + else if (current >= 'a' and current <= 'f') + { + codepoint += ((current - 0x57) << factor); + } + else + { + return -1; + } + } + + assert(0x0000 <= codepoint and codepoint <= 0xFFFF); + return codepoint; + } + + /*! + @brief check if the next byte(s) are inside a given range + + Adds the current byte and, for each passed range, reads a new byte and + checks if it is inside the range. If a violation was detected, set up an + error message and return false. Otherwise, return true. + + @param[in] ranges list of integers; interpreted as list of pairs of + inclusive lower and upper bound, respectively + + @pre The passed list @a ranges must have 2, 4, or 6 elements; that is, + 1, 2, or 3 pairs. This precondition is enforced by an assertion. + + @return true if and only if no range violation was detected + */ + bool next_byte_in_range(std::initializer_list<int> ranges) + { + assert(ranges.size() == 2 or ranges.size() == 4 or ranges.size() == 6); + add(current); + + for (auto range = ranges.begin(); range != ranges.end(); ++range) + { + get(); + if (JSON_LIKELY(*range <= current and current <= *(++range))) + { + add(current); + } + else + { + error_message = "invalid string: ill-formed UTF-8 byte"; + return false; + } + } + + return true; + } + + /*! + @brief scan a string literal + + This function scans a string according to Sect. 7 of RFC 7159. While + scanning, bytes are escaped and copied into buffer yytext. Then the function + returns successfully, yytext is *not* null-terminated (as it may contain \0 + bytes), and yytext.size() is the number of bytes in the string. + + @return token_type::value_string if string could be successfully scanned, + token_type::parse_error otherwise + + @note In case of errors, variable error_message contains a textual + description. + */ + token_type scan_string() + { + // reset yytext (ignore opening quote) + reset(); + + // we entered the function by reading an open quote + assert(current == '\"'); + + while (true) + { + // get next character + switch (get()) + { + // end of file while parsing string + case std::char_traits<char>::eof(): + { + error_message = "invalid string: missing closing quote"; + return token_type::parse_error; + } + + // closing quote + case '\"': + { + return token_type::value_string; + } + + // escapes + case '\\': + { + switch (get()) + { + // quotation mark + case '\"': + add('\"'); + break; + // reverse solidus + case '\\': + add('\\'); + break; + // solidus + case '/': + add('/'); + break; + // backspace + case 'b': + add('\b'); + break; + // form feed + case 'f': + add('\f'); + break; + // line feed + case 'n': + add('\n'); + break; + // carriage return + case 'r': + add('\r'); + break; + // tab + case 't': + add('\t'); + break; + + // unicode escapes + case 'u': + { + const int codepoint1 = get_codepoint(); + int codepoint = codepoint1; // start with codepoint1 + + if (JSON_UNLIKELY(codepoint1 == -1)) + { + error_message = "invalid string: '\\u' must be followed by 4 hex digits"; + return token_type::parse_error; + } + + // check if code point is a high surrogate + if (0xD800 <= codepoint1 and codepoint1 <= 0xDBFF) + { + // expect next \uxxxx entry + if (JSON_LIKELY(get() == '\\' and get() == 'u')) + { + const int codepoint2 = get_codepoint(); + + if (JSON_UNLIKELY(codepoint2 == -1)) + { + error_message = "invalid string: '\\u' must be followed by 4 hex digits"; + return token_type::parse_error; + } + + // check if codepoint2 is a low surrogate + if (JSON_LIKELY(0xDC00 <= codepoint2 and codepoint2 <= 0xDFFF)) + { + // overwrite codepoint + codepoint = + // high surrogate occupies the most significant 22 bits + (codepoint1 << 10) + // low surrogate occupies the least significant 15 bits + + codepoint2 + // there is still the 0xD800, 0xDC00 and 0x10000 noise + // in the result so we have to subtract with: + // (0xD800 << 10) + DC00 - 0x10000 = 0x35FDC00 + - 0x35FDC00; + } + else + { + error_message = "invalid string: surrogate U+DC00..U+DFFF must be followed by U+DC00..U+DFFF"; + return token_type::parse_error; + } + } + else + { + error_message = "invalid string: surrogate U+DC00..U+DFFF must be followed by U+DC00..U+DFFF"; + return token_type::parse_error; + } + } + else + { + if (JSON_UNLIKELY(0xDC00 <= codepoint1 and codepoint1 <= 0xDFFF)) + { + error_message = "invalid string: surrogate U+DC00..U+DFFF must follow U+D800..U+DBFF"; + return token_type::parse_error; + } + } + + // result of the above calculation yields a proper codepoint + assert(0x00 <= codepoint and codepoint <= 0x10FFFF); + + // translate codepoint into bytes + if (codepoint < 0x80) + { + // 1-byte characters: 0xxxxxxx (ASCII) + add(codepoint); + } + else if (codepoint <= 0x7FF) + { + // 2-byte characters: 110xxxxx 10xxxxxx + add(0xC0 | (codepoint >> 6)); + add(0x80 | (codepoint & 0x3F)); + } + else if (codepoint <= 0xFFFF) + { + // 3-byte characters: 1110xxxx 10xxxxxx 10xxxxxx + add(0xE0 | (codepoint >> 12)); + add(0x80 | ((codepoint >> 6) & 0x3F)); + add(0x80 | (codepoint & 0x3F)); + } + else + { + // 4-byte characters: 11110xxx 10xxxxxx 10xxxxxx 10xxxxxx + add(0xF0 | (codepoint >> 18)); + add(0x80 | ((codepoint >> 12) & 0x3F)); + add(0x80 | ((codepoint >> 6) & 0x3F)); + add(0x80 | (codepoint & 0x3F)); + } + + break; + } + + // other characters after escape + default: + error_message = "invalid string: forbidden character after backslash"; + return token_type::parse_error; + } + + break; + } + + // invalid control characters + case 0x00: + case 0x01: + case 0x02: + case 0x03: + case 0x04: + case 0x05: + case 0x06: + case 0x07: + case 0x08: + case 0x09: + case 0x0A: + case 0x0B: + case 0x0C: + case 0x0D: + case 0x0E: + case 0x0F: + case 0x10: + case 0x11: + case 0x12: + case 0x13: + case 0x14: + case 0x15: + case 0x16: + case 0x17: + case 0x18: + case 0x19: + case 0x1A: + case 0x1B: + case 0x1C: + case 0x1D: + case 0x1E: + case 0x1F: + { + error_message = "invalid string: control character must be escaped"; + return token_type::parse_error; + } + + // U+0020..U+007F (except U+0022 (quote) and U+005C (backspace)) + case 0x20: + case 0x21: + case 0x23: + case 0x24: + case 0x25: + case 0x26: + case 0x27: + case 0x28: + case 0x29: + case 0x2A: + case 0x2B: + case 0x2C: + case 0x2D: + case 0x2E: + case 0x2F: + case 0x30: + case 0x31: + case 0x32: + case 0x33: + case 0x34: + case 0x35: + case 0x36: + case 0x37: + case 0x38: + case 0x39: + case 0x3A: + case 0x3B: + case 0x3C: + case 0x3D: + case 0x3E: + case 0x3F: + case 0x40: + case 0x41: + case 0x42: + case 0x43: + case 0x44: + case 0x45: + case 0x46: + case 0x47: + case 0x48: + case 0x49: + case 0x4A: + case 0x4B: + case 0x4C: + case 0x4D: + case 0x4E: + case 0x4F: + case 0x50: + case 0x51: + case 0x52: + case 0x53: + case 0x54: + case 0x55: + case 0x56: + case 0x57: + case 0x58: + case 0x59: + case 0x5A: + case 0x5B: + case 0x5D: + case 0x5E: + case 0x5F: + case 0x60: + case 0x61: + case 0x62: + case 0x63: + case 0x64: + case 0x65: + case 0x66: + case 0x67: + case 0x68: + case 0x69: + case 0x6A: + case 0x6B: + case 0x6C: + case 0x6D: + case 0x6E: + case 0x6F: + case 0x70: + case 0x71: + case 0x72: + case 0x73: + case 0x74: + case 0x75: + case 0x76: + case 0x77: + case 0x78: + case 0x79: + case 0x7A: + case 0x7B: + case 0x7C: + case 0x7D: + case 0x7E: + case 0x7F: + { + add(current); + break; + } + + // U+0080..U+07FF: bytes C2..DF 80..BF + case 0xC2: + case 0xC3: + case 0xC4: + case 0xC5: + case 0xC6: + case 0xC7: + case 0xC8: + case 0xC9: + case 0xCA: + case 0xCB: + case 0xCC: + case 0xCD: + case 0xCE: + case 0xCF: + case 0xD0: + case 0xD1: + case 0xD2: + case 0xD3: + case 0xD4: + case 0xD5: + case 0xD6: + case 0xD7: + case 0xD8: + case 0xD9: + case 0xDA: + case 0xDB: + case 0xDC: + case 0xDD: + case 0xDE: + case 0xDF: + { + if (JSON_UNLIKELY(not next_byte_in_range({0x80, 0xBF}))) + { + return token_type::parse_error; + } + break; + } + + // U+0800..U+0FFF: bytes E0 A0..BF 80..BF + case 0xE0: + { + if (JSON_UNLIKELY(not (next_byte_in_range({0xA0, 0xBF, 0x80, 0xBF})))) + { + return token_type::parse_error; + } + break; + } + + // U+1000..U+CFFF: bytes E1..EC 80..BF 80..BF + // U+E000..U+FFFF: bytes EE..EF 80..BF 80..BF + case 0xE1: + case 0xE2: + case 0xE3: + case 0xE4: + case 0xE5: + case 0xE6: + case 0xE7: + case 0xE8: + case 0xE9: + case 0xEA: + case 0xEB: + case 0xEC: + case 0xEE: + case 0xEF: + { + if (JSON_UNLIKELY(not (next_byte_in_range({0x80, 0xBF, 0x80, 0xBF})))) + { + return token_type::parse_error; + } + break; + } + + // U+D000..U+D7FF: bytes ED 80..9F 80..BF + case 0xED: + { + if (JSON_UNLIKELY(not (next_byte_in_range({0x80, 0x9F, 0x80, 0xBF})))) + { + return token_type::parse_error; + } + break; + } + + // U+10000..U+3FFFF F0 90..BF 80..BF 80..BF + case 0xF0: + { + if (JSON_UNLIKELY(not (next_byte_in_range({0x90, 0xBF, 0x80, 0xBF, 0x80, 0xBF})))) + { + return token_type::parse_error; + } + break; + } + + // U+40000..U+FFFFF F1..F3 80..BF 80..BF 80..BF + case 0xF1: + case 0xF2: + case 0xF3: + { + if (JSON_UNLIKELY(not (next_byte_in_range({0x80, 0xBF, 0x80, 0xBF, 0x80, 0xBF})))) + { + return token_type::parse_error; + } + break; + } + + // U+100000..U+10FFFF F4 80..8F 80..BF 80..BF + case 0xF4: + { + if (JSON_UNLIKELY(not (next_byte_in_range({0x80, 0x8F, 0x80, 0xBF, 0x80, 0xBF})))) + { + return token_type::parse_error; + } + break; + } + + // remaining bytes (80..C1 and F5..FF) are ill-formed + default: + { + error_message = "invalid string: ill-formed UTF-8 byte"; + return token_type::parse_error; + } + } + } + } + + static void strtof(float& f, const char* str, char** endptr) noexcept + { + f = std::strtof(str, endptr); + } + + static void strtof(double& f, const char* str, char** endptr) noexcept + { + f = std::strtod(str, endptr); + } + + static void strtof(long double& f, const char* str, char** endptr) noexcept + { + f = std::strtold(str, endptr); + } + + /*! + @brief scan a number literal + + This function scans a string according to Sect. 6 of RFC 7159. + + The function is realized with a deterministic finite state machine derived + from the grammar described in RFC 7159. Starting in state "init", the + input is read and used to determined the next state. Only state "done" + accepts the number. State "error" is a trap state to model errors. In the + table below, "anything" means any character but the ones listed before. + + state | 0 | 1-9 | e E | + | - | . | anything + ---------|----------|----------|----------|---------|---------|----------|----------- + init | zero | any1 | [error] | [error] | minus | [error] | [error] + minus | zero | any1 | [error] | [error] | [error] | [error] | [error] + zero | done | done | exponent | done | done | decimal1 | done + any1 | any1 | any1 | exponent | done | done | decimal1 | done + decimal1 | decimal2 | [error] | [error] | [error] | [error] | [error] | [error] + decimal2 | decimal2 | decimal2 | exponent | done | done | done | done + exponent | any2 | any2 | [error] | sign | sign | [error] | [error] + sign | any2 | any2 | [error] | [error] | [error] | [error] | [error] + any2 | any2 | any2 | done | done | done | done | done + + The state machine is realized with one label per state (prefixed with + "scan_number_") and `goto` statements between them. The state machine + contains cycles, but any cycle can be left when EOF is read. Therefore, + the function is guaranteed to terminate. + + During scanning, the read bytes are stored in yytext. This string is + then converted to a signed integer, an unsigned integer, or a + floating-point number. + + @return token_type::value_unsigned, token_type::value_integer, or + token_type::value_float if number could be successfully scanned, + token_type::parse_error otherwise + + @note The scanner is independent of the current locale. Internally, the + locale's decimal point is used instead of `.` to work with the + locale-dependent converters. + */ + token_type scan_number() + { + // reset yytext to store the number's bytes + reset(); + + // the type of the parsed number; initially set to unsigned; will be + // changed if minus sign, decimal point or exponent is read + token_type number_type = token_type::value_unsigned; + + // state (init): we just found out we need to scan a number + switch (current) + { + case '-': + { + add(current); + goto scan_number_minus; + } + + case '0': + { + add(current); + goto scan_number_zero; + } + + case '1': + case '2': + case '3': + case '4': + case '5': + case '6': + case '7': + case '8': + case '9': + { + add(current); + goto scan_number_any1; + } + + default: + { + // all other characters are rejected outside scan_number() + assert(false); // LCOV_EXCL_LINE + } + } + +scan_number_minus: + // state: we just parsed a leading minus sign + number_type = token_type::value_integer; + switch (get()) + { + case '0': + { + add(current); + goto scan_number_zero; + } + + case '1': + case '2': + case '3': + case '4': + case '5': + case '6': + case '7': + case '8': + case '9': + { + add(current); + goto scan_number_any1; + } + + default: + { + error_message = "invalid number; expected digit after '-'"; + return token_type::parse_error; + } + } + +scan_number_zero: + // state: we just parse a zero (maybe with a leading minus sign) + switch (get()) + { + case '.': + { + add(decimal_point_char); + goto scan_number_decimal1; + } + + case 'e': + case 'E': + { + add(current); + goto scan_number_exponent; + } + + default: + goto scan_number_done; + } + +scan_number_any1: + // state: we just parsed a number 0-9 (maybe with a leading minus sign) + switch (get()) + { + case '0': + case '1': + case '2': + case '3': + case '4': + case '5': + case '6': + case '7': + case '8': + case '9': + { + add(current); + goto scan_number_any1; + } + + case '.': + { + add(decimal_point_char); + goto scan_number_decimal1; + } + + case 'e': + case 'E': + { + add(current); + goto scan_number_exponent; + } + + default: + goto scan_number_done; + } + +scan_number_decimal1: + // state: we just parsed a decimal point + number_type = token_type::value_float; + switch (get()) + { + case '0': + case '1': + case '2': + case '3': + case '4': + case '5': + case '6': + case '7': + case '8': + case '9': + { + add(current); + goto scan_number_decimal2; + } + + default: + { + error_message = "invalid number; expected digit after '.'"; + return token_type::parse_error; + } + } + +scan_number_decimal2: + // we just parsed at least one number after a decimal point + switch (get()) + { + case '0': + case '1': + case '2': + case '3': + case '4': + case '5': + case '6': + case '7': + case '8': + case '9': + { + add(current); + goto scan_number_decimal2; + } + + case 'e': + case 'E': + { + add(current); + goto scan_number_exponent; + } + + default: + goto scan_number_done; + } + +scan_number_exponent: + // we just parsed an exponent + number_type = token_type::value_float; + switch (get()) + { + case '+': + case '-': + { + add(current); + goto scan_number_sign; + } + + case '0': + case '1': + case '2': + case '3': + case '4': + case '5': + case '6': + case '7': + case '8': + case '9': + { + add(current); + goto scan_number_any2; + } + + default: + { + error_message = + "invalid number; expected '+', '-', or digit after exponent"; + return token_type::parse_error; + } + } + +scan_number_sign: + // we just parsed an exponent sign + switch (get()) + { + case '0': + case '1': + case '2': + case '3': + case '4': + case '5': + case '6': + case '7': + case '8': + case '9': + { + add(current); + goto scan_number_any2; + } + + default: + { + error_message = "invalid number; expected digit after exponent sign"; + return token_type::parse_error; + } + } + +scan_number_any2: + // we just parsed a number after the exponent or exponent sign + switch (get()) + { + case '0': + case '1': + case '2': + case '3': + case '4': + case '5': + case '6': + case '7': + case '8': + case '9': + { + add(current); + goto scan_number_any2; + } + + default: + goto scan_number_done; + } + +scan_number_done: + // unget the character after the number (we only read it to know that + // we are done scanning a number) + unget(); + + char* endptr = nullptr; + errno = 0; + + // try to parse integers first and fall back to floats + if (number_type == token_type::value_unsigned) + { + const auto x = std::strtoull(yytext.data(), &endptr, 10); + + // we checked the number format before + assert(endptr == yytext.data() + yytext.size()); + + if (errno == 0) + { + value_unsigned = static_cast<number_unsigned_t>(x); + if (value_unsigned == x) + { + return token_type::value_unsigned; + } + } + } + else if (number_type == token_type::value_integer) + { + const auto x = std::strtoll(yytext.data(), &endptr, 10); + + // we checked the number format before + assert(endptr == yytext.data() + yytext.size()); + + if (errno == 0) + { + value_integer = static_cast<number_integer_t>(x); + if (value_integer == x) + { + return token_type::value_integer; + } + } + } + + // this code is reached if we parse a floating-point number or if an + // integer conversion above failed + strtof(value_float, yytext.data(), &endptr); + + // we checked the number format before + assert(endptr == yytext.data() + yytext.size()); + + return token_type::value_float; + } + + /*! + @param[in] literal_text the literal text to expect + @param[in] length the length of the passed literal text + @param[in] return_type the token type to return on success + */ + token_type scan_literal(const char* literal_text, const std::size_t length, + token_type return_type) + { + assert(current == literal_text[0]); + for (std::size_t i = 1; i < length; ++i) + { + if (JSON_UNLIKELY(get() != literal_text[i])) + { + error_message = "invalid literal"; + return token_type::parse_error; + } + } + return return_type; + } + + ///////////////////// + // input management + ///////////////////// + + /// reset yytext; current character is beginning of token + void reset() noexcept + { + yytext.clear(); + token_string.clear(); + token_string.push_back(std::char_traits<char>::to_char_type(current)); + } + + /* + @brief get next character from the input + + This function provides the interface to the used input adapter. It does + not throw in case the input reached EOF, but returns a + `std::char_traits<char>::eof()` in that case. Stores the scanned characters + for use in error messages. + + @return character read from the input + */ + std::char_traits<char>::int_type get() + { + ++chars_read; + current = ia->get_character(); + if (JSON_LIKELY(current != std::char_traits<char>::eof())) + { + token_string.push_back(std::char_traits<char>::to_char_type(current)); + } + return current; + } + + /// unget current character (return it again on next get) + void unget() + { + --chars_read; + if (JSON_LIKELY(current != std::char_traits<char>::eof())) + { + ia->unget_character(); + assert(token_string.size() != 0); + token_string.pop_back(); + } + } + + /// add a character to yytext + void add(int c) + { + yytext.push_back(std::char_traits<char>::to_char_type(c)); + } + + public: + ///////////////////// + // value getters + ///////////////////// + + /// return integer value + constexpr number_integer_t get_number_integer() const noexcept + { + return value_integer; + } + + /// return unsigned integer value + constexpr number_unsigned_t get_number_unsigned() const noexcept + { + return value_unsigned; + } + + /// return floating-point value + constexpr number_float_t get_number_float() const noexcept + { + return value_float; + } + + /// return current string value (implicitly resets the token; useful only once) + std::string move_string() + { + return std::move(yytext); + } + + ///////////////////// + // diagnostics + ///////////////////// + + /// return position of last read token + constexpr std::size_t get_position() const noexcept + { + return chars_read; + } + + /// return the last read token (for errors only). Will never contain EOF + /// (an arbitrary value that is not a valid char value, often -1), because + /// 255 may legitimately occur. May contain NUL, which should be escaped. + std::string get_token_string() const + { + // escape control characters + std::string result; + for (const auto c : token_string) + { + if ('\x00' <= c and c <= '\x1F') + { + // escape control characters + std::stringstream ss; + ss << "<U+" << std::setw(4) << std::uppercase << std::setfill('0') + << std::hex << static_cast<int>(c) << ">"; + result += ss.str(); + } + else + { + // add character as is + result.push_back(c); + } + } + + return result; + } + + /// return syntax error message + constexpr const char* get_error_message() const noexcept + { + return error_message; + } + + ///////////////////// + // actual scanner + ///////////////////// + + token_type scan() + { + // read next character and ignore whitespace + do + { + get(); + } + while (current == ' ' or current == '\t' or current == '\n' or current == '\r'); + + switch (current) + { + // structural characters + case '[': + return token_type::begin_array; + case ']': + return token_type::end_array; + case '{': + return token_type::begin_object; + case '}': + return token_type::end_object; + case ':': + return token_type::name_separator; + case ',': + return token_type::value_separator; + + // literals + case 't': + return scan_literal("true", 4, token_type::literal_true); + case 'f': + return scan_literal("false", 5, token_type::literal_false); + case 'n': + return scan_literal("null", 4, token_type::literal_null); + + // string + case '\"': + return scan_string(); + + // number + case '-': + case '0': + case '1': + case '2': + case '3': + case '4': + case '5': + case '6': + case '7': + case '8': + case '9': + return scan_number(); + + // end of input (the null byte is needed when parsing from + // string literals) + case '\0': + case std::char_traits<char>::eof(): + return token_type::end_of_input; + + // error + default: + error_message = "invalid literal"; + return token_type::parse_error; + } + } + + private: + /// input adapter + detail::input_adapter_t ia = nullptr; + + /// the current character + std::char_traits<char>::int_type current = std::char_traits<char>::eof(); + + /// the number of characters read + std::size_t chars_read = 0; + + /// raw input token string (for error messages) + std::vector<char> token_string {}; + + /// buffer for variable-length tokens (numbers, strings) + std::string yytext {}; + + /// a description of occurred lexer errors + const char* error_message = ""; + + // number values + number_integer_t value_integer = 0; + number_unsigned_t value_unsigned = 0; + number_float_t value_float = 0; + + /// the decimal point + const char decimal_point_char = '.'; +}; + +/*! +@brief syntax analysis + +This class implements a recursive decent parser. +*/ +template<typename BasicJsonType> +class parser +{ + using number_integer_t = typename BasicJsonType::number_integer_t; + using number_unsigned_t = typename BasicJsonType::number_unsigned_t; + using number_float_t = typename BasicJsonType::number_float_t; + using lexer_t = lexer<BasicJsonType>; + using token_type = typename lexer_t::token_type; + + public: + enum class parse_event_t : uint8_t + { + /// the parser read `{` and started to process a JSON object + object_start, + /// the parser read `}` and finished processing a JSON object + object_end, + /// the parser read `[` and started to process a JSON array + array_start, + /// the parser read `]` and finished processing a JSON array + array_end, + /// the parser read a key of a value in an object + key, + /// the parser finished reading a JSON value + value + }; + + using parser_callback_t = + std::function<bool(int depth, parse_event_t event, BasicJsonType& parsed)>; + + /// a parser reading from an input adapter + explicit parser(detail::input_adapter_t adapter, + const parser_callback_t cb = nullptr, + const bool allow_exceptions_ = true) + : callback(cb), m_lexer(adapter), allow_exceptions(allow_exceptions_) + {} + + /*! + @brief public parser interface + + @param[in] strict whether to expect the last token to be EOF + @param[in,out] result parsed JSON value + + @throw parse_error.101 in case of an unexpected token + @throw parse_error.102 if to_unicode fails or surrogate error + @throw parse_error.103 if to_unicode fails + */ + void parse(const bool strict, BasicJsonType& result) + { + // read first token + get_token(); + + parse_internal(true, result); + result.assert_invariant(); + + // in strict mode, input must be completely read + if (strict) + { + get_token(); + expect(token_type::end_of_input); + } + + // in case of an error, return discarded value + if (errored) + { + result = value_t::discarded; + return; + } + + // set top-level value to null if it was discarded by the callback + // function + if (result.is_discarded()) + { + result = nullptr; + } + } + + /*! + @brief public accept interface + + @param[in] strict whether to expect the last token to be EOF + @return whether the input is a proper JSON text + */ + bool accept(const bool strict = true) + { + // read first token + get_token(); + + if (not accept_internal()) + { + return false; + } + + // strict => last token must be EOF + return not strict or (get_token() == token_type::end_of_input); + } + + private: + /*! + @brief the actual parser + @throw parse_error.101 in case of an unexpected token + @throw parse_error.102 if to_unicode fails or surrogate error + @throw parse_error.103 if to_unicode fails + */ + void parse_internal(bool keep, BasicJsonType& result) + { + // never parse after a parse error was detected + assert(not errored); + + // start with a discarded value + if (not result.is_discarded()) + { + result.m_value.destroy(result.m_type); + result.m_type = value_t::discarded; + } + + switch (last_token) + { + case token_type::begin_object: + { + if (keep) + { + if (callback) + { + keep = callback(depth++, parse_event_t::object_start, result); + } + + if (not callback or keep) + { + // explicitly set result to object to cope with {} + result.m_type = value_t::object; + result.m_value = value_t::object; + } + } + + // read next token + get_token(); + + // closing } -> we are done + if (last_token == token_type::end_object) + { + if (keep and callback and not callback(--depth, parse_event_t::object_end, result)) + { + result.m_value.destroy(result.m_type); + result.m_type = value_t::discarded; + } + break; + } + + // parse values + std::string key; + BasicJsonType value; + while (true) + { + // store key + if (not expect(token_type::value_string)) + { + return; + } + key = m_lexer.move_string(); + + bool keep_tag = false; + if (keep) + { + if (callback) + { + BasicJsonType k(key); + keep_tag = callback(depth, parse_event_t::key, k); + } + else + { + keep_tag = true; + } + } + + // parse separator (:) + get_token(); + if (not expect(token_type::name_separator)) + { + return; + } + + // parse and add value + get_token(); + value.m_value.destroy(value.m_type); + value.m_type = value_t::discarded; + parse_internal(keep, value); + + if (JSON_UNLIKELY(errored)) + { + return; + } + + if (keep and keep_tag and not value.is_discarded()) + { + result.m_value.object->emplace(std::move(key), std::move(value)); + } + + // comma -> next value + get_token(); + if (last_token == token_type::value_separator) + { + get_token(); + continue; + } + + // closing } + if (not expect(token_type::end_object)) + { + return; + } + break; + } + + if (keep and callback and not callback(--depth, parse_event_t::object_end, result)) + { + result.m_value.destroy(result.m_type); + result.m_type = value_t::discarded; + } + break; + } + + case token_type::begin_array: + { + if (keep) + { + if (callback) + { + keep = callback(depth++, parse_event_t::array_start, result); + } + + if (not callback or keep) + { + // explicitly set result to array to cope with [] + result.m_type = value_t::array; + result.m_value = value_t::array; + } + } + + // read next token + get_token(); + + // closing ] -> we are done + if (last_token == token_type::end_array) + { + if (callback and not callback(--depth, parse_event_t::array_end, result)) + { + result.m_value.destroy(result.m_type); + result.m_type = value_t::discarded; + } + break; + } + + // parse values + BasicJsonType value; + while (true) + { + // parse value + value.m_value.destroy(value.m_type); + value.m_type = value_t::discarded; + parse_internal(keep, value); + + if (JSON_UNLIKELY(errored)) + { + return; + } + + if (keep and not value.is_discarded()) + { + result.m_value.array->push_back(std::move(value)); + } + + // comma -> next value + get_token(); + if (last_token == token_type::value_separator) + { + get_token(); + continue; + } + + // closing ] + if (not expect(token_type::end_array)) + { + return; + } + break; + } + + if (keep and callback and not callback(--depth, parse_event_t::array_end, result)) + { + result.m_value.destroy(result.m_type); + result.m_type = value_t::discarded; + } + break; + } + + case token_type::literal_null: + { + result.m_type = value_t::null; + break; + } + + case token_type::value_string: + { + result.m_type = value_t::string; + result.m_value = m_lexer.move_string(); + break; + } + + case token_type::literal_true: + { + result.m_type = value_t::boolean; + result.m_value = true; + break; + } + + case token_type::literal_false: + { + result.m_type = value_t::boolean; + result.m_value = false; + break; + } + + case token_type::value_unsigned: + { + result.m_type = value_t::number_unsigned; + result.m_value = m_lexer.get_number_unsigned(); + break; + } + + case token_type::value_integer: + { + result.m_type = value_t::number_integer; + result.m_value = m_lexer.get_number_integer(); + break; + } + + case token_type::value_float: + { + result.m_type = value_t::number_float; + result.m_value = m_lexer.get_number_float(); + + // throw in case of infinity or NAN + if (JSON_UNLIKELY(not std::isfinite(result.m_value.number_float))) + { + if (allow_exceptions) + { + JSON_THROW(out_of_range::create(406, "number overflow parsing '" + + m_lexer.get_token_string() + "'")); + } + expect(token_type::uninitialized); + } + break; + } + + case token_type::parse_error: + { + // using "uninitialized" to avoid "expected" message + if (not expect(token_type::uninitialized)) + { + return; + } + break; // LCOV_EXCL_LINE + } + + default: + { + // the last token was unexpected; we expected a value + if (not expect(token_type::literal_or_value)) + { + return; + } + break; // LCOV_EXCL_LINE + } + } + + if (keep and callback and not callback(depth, parse_event_t::value, result)) + { + result.m_type = value_t::discarded; + } + } + + /*! + @brief the actual acceptor + + @invariant 1. The last token is not yet processed. Therefore, the caller + of this function must make sure a token has been read. + 2. When this function returns, the last token is processed. + That is, the last read character was already considered. + + This invariant makes sure that no token needs to be "unput". + */ + bool accept_internal() + { + switch (last_token) + { + case token_type::begin_object: + { + // read next token + get_token(); + + // closing } -> we are done + if (last_token == token_type::end_object) + { + return true; + } + + // parse values + while (true) + { + // parse key + if (last_token != token_type::value_string) + { + return false; + } + + // parse separator (:) + get_token(); + if (last_token != token_type::name_separator) + { + return false; + } + + // parse value + get_token(); + if (not accept_internal()) + { + return false; + } + + // comma -> next value + get_token(); + if (last_token == token_type::value_separator) + { + get_token(); + continue; + } + + // closing } + return (last_token == token_type::end_object); + } + } + + case token_type::begin_array: + { + // read next token + get_token(); + + // closing ] -> we are done + if (last_token == token_type::end_array) + { + return true; + } + + // parse values + while (true) + { + // parse value + if (not accept_internal()) + { + return false; + } + + // comma -> next value + get_token(); + if (last_token == token_type::value_separator) + { + get_token(); + continue; + } + + // closing ] + return (last_token == token_type::end_array); + } + } + + case token_type::value_float: + { + // reject infinity or NAN + return std::isfinite(m_lexer.get_number_float()); + } + + case token_type::literal_false: + case token_type::literal_null: + case token_type::literal_true: + case token_type::value_integer: + case token_type::value_string: + case token_type::value_unsigned: + return true; + + default: // the last token was unexpected + return false; + } + } + + /// get next token from lexer + token_type get_token() + { + return (last_token = m_lexer.scan()); + } + + /*! + @throw parse_error.101 if expected token did not occur + */ + bool expect(token_type t) + { + if (JSON_UNLIKELY(t != last_token)) + { + errored = true; + expected = t; + if (allow_exceptions) + { + throw_exception(); + } + else + { + return false; + } + } + + return true; + } + + [[noreturn]] void throw_exception() const + { + std::string error_msg = "syntax error - "; + if (last_token == token_type::parse_error) + { + error_msg += std::string(m_lexer.get_error_message()) + "; last read: '" + + m_lexer.get_token_string() + "'"; + } + else + { + error_msg += "unexpected " + std::string(lexer_t::token_type_name(last_token)); + } + + if (expected != token_type::uninitialized) + { + error_msg += "; expected " + std::string(lexer_t::token_type_name(expected)); + } + + JSON_THROW(parse_error::create(101, m_lexer.get_position(), error_msg)); + } + + private: + /// current level of recursion + int depth = 0; + /// callback function + const parser_callback_t callback = nullptr; + /// the type of the last read token + token_type last_token = token_type::uninitialized; + /// the lexer + lexer_t m_lexer; + /// whether a syntax error occurred + bool errored = false; + /// possible reason for the syntax error + token_type expected = token_type::uninitialized; + /// whether to throw exceptions in case of errors + const bool allow_exceptions = true; +}; + +/////////////// +// iterators // +/////////////// + +/*! +@brief an iterator for primitive JSON types + +This class models an iterator for primitive JSON types (boolean, number, +string). It's only purpose is to allow the iterator/const_iterator classes +to "iterate" over primitive values. Internally, the iterator is modeled by +a `difference_type` variable. Value begin_value (`0`) models the begin, +end_value (`1`) models past the end. +*/ +class primitive_iterator_t +{ + public: + using difference_type = std::ptrdiff_t; + + constexpr difference_type get_value() const noexcept + { + return m_it; + } + + /// set iterator to a defined beginning + void set_begin() noexcept + { + m_it = begin_value; + } + + /// set iterator to a defined past the end + void set_end() noexcept + { + m_it = end_value; + } + + /// return whether the iterator can be dereferenced + constexpr bool is_begin() const noexcept + { + return m_it == begin_value; + } + + /// return whether the iterator is at end + constexpr bool is_end() const noexcept + { + return m_it == end_value; + } + + friend constexpr bool operator==(primitive_iterator_t lhs, primitive_iterator_t rhs) noexcept + { + return lhs.m_it == rhs.m_it; + } + + friend constexpr bool operator<(primitive_iterator_t lhs, primitive_iterator_t rhs) noexcept + { + return lhs.m_it < rhs.m_it; + } + + primitive_iterator_t operator+(difference_type i) + { + auto result = *this; + result += i; + return result; + } + + friend constexpr difference_type operator-(primitive_iterator_t lhs, primitive_iterator_t rhs) noexcept + { + return lhs.m_it - rhs.m_it; + } + + friend std::ostream& operator<<(std::ostream& os, primitive_iterator_t it) + { + return os << it.m_it; + } + + primitive_iterator_t& operator++() + { + ++m_it; + return *this; + } + + primitive_iterator_t const operator++(int) + { + auto result = *this; + m_it++; + return result; + } + + primitive_iterator_t& operator--() + { + --m_it; + return *this; + } + + primitive_iterator_t const operator--(int) + { + auto result = *this; + m_it--; + return result; + } + + primitive_iterator_t& operator+=(difference_type n) + { + m_it += n; + return *this; + } + + primitive_iterator_t& operator-=(difference_type n) + { + m_it -= n; + return *this; + } + + private: + static constexpr difference_type begin_value = 0; + static constexpr difference_type end_value = begin_value + 1; + + /// iterator as signed integer type + difference_type m_it = (std::numeric_limits<std::ptrdiff_t>::min)(); +}; + +/*! +@brief an iterator value + +@note This structure could easily be a union, but MSVC currently does not allow +unions members with complex constructors, see https://github.com/nlohmann/json/pull/105. +*/ +template<typename BasicJsonType> struct internal_iterator +{ + /// iterator for JSON objects + typename BasicJsonType::object_t::iterator object_iterator {}; + /// iterator for JSON arrays + typename BasicJsonType::array_t::iterator array_iterator {}; + /// generic iterator for all other types + primitive_iterator_t primitive_iterator {}; +}; + +template<typename IteratorType> class iteration_proxy; + +/*! +@brief a template for a bidirectional iterator for the @ref basic_json class + +This class implements a both iterators (iterator and const_iterator) for the +@ref basic_json class. + +@note An iterator is called *initialized* when a pointer to a JSON value has + been set (e.g., by a constructor or a copy assignment). If the iterator is + default-constructed, it is *uninitialized* and most methods are undefined. + **The library uses assertions to detect calls on uninitialized iterators.** + +@requirement The class satisfies the following concept requirements: +- +[BidirectionalIterator](http://en.cppreference.com/w/cpp/concept/BidirectionalIterator): + The iterator that can be moved can be moved in both directions (i.e. + incremented and decremented). + +@since version 1.0.0, simplified in version 2.0.9, change to bidirectional + iterators in version 3.0.0 (see https://github.com/nlohmann/json/issues/593) +*/ +template<typename BasicJsonType> +class iter_impl +{ + /// allow basic_json to access private members + friend iter_impl<typename std::conditional<std::is_const<BasicJsonType>::value, typename std::remove_const<BasicJsonType>::type, const BasicJsonType>::type>; + friend BasicJsonType; + friend iteration_proxy<iter_impl>; + + using object_t = typename BasicJsonType::object_t; + using array_t = typename BasicJsonType::array_t; + // make sure BasicJsonType is basic_json or const basic_json + static_assert(is_basic_json<typename std::remove_const<BasicJsonType>::type>::value, + "iter_impl only accepts (const) basic_json"); + + public: + + /// The std::iterator class template (used as a base class to provide typedefs) is deprecated in C++17. + /// The C++ Standard has never required user-defined iterators to derive from std::iterator. + /// A user-defined iterator should provide publicly accessible typedefs named + /// iterator_category, value_type, difference_type, pointer, and reference. + /// Note that value_type is required to be non-const, even for constant iterators. + using iterator_category = std::bidirectional_iterator_tag; + + /// the type of the values when the iterator is dereferenced + using value_type = typename BasicJsonType::value_type; + /// a type to represent differences between iterators + using difference_type = typename BasicJsonType::difference_type; + /// defines a pointer to the type iterated over (value_type) + using pointer = typename std::conditional<std::is_const<BasicJsonType>::value, + typename BasicJsonType::const_pointer, + typename BasicJsonType::pointer>::type; + /// defines a reference to the type iterated over (value_type) + using reference = + typename std::conditional<std::is_const<BasicJsonType>::value, + typename BasicJsonType::const_reference, + typename BasicJsonType::reference>::type; + + /// default constructor + iter_impl() = default; + + /*! + @brief constructor for a given JSON instance + @param[in] object pointer to a JSON object for this iterator + @pre object != nullptr + @post The iterator is initialized; i.e. `m_object != nullptr`. + */ + explicit iter_impl(pointer object) noexcept : m_object(object) + { + assert(m_object != nullptr); + + switch (m_object->m_type) + { + case value_t::object: + { + m_it.object_iterator = typename object_t::iterator(); + break; + } + + case value_t::array: + { + m_it.array_iterator = typename array_t::iterator(); + break; + } + + default: + { + m_it.primitive_iterator = primitive_iterator_t(); + break; + } + } + } + + /*! + @note The conventional copy constructor and copy assignment are implicitly + defined. Combined with the following converting constructor and + assignment, they support: (1) copy from iterator to iterator, (2) + copy from const iterator to const iterator, and (3) conversion from + iterator to const iterator. However conversion from const iterator + to iterator is not defined. + */ + + /*! + @brief converting constructor + @param[in] other non-const iterator to copy from + @note It is not checked whether @a other is initialized. + */ + iter_impl(const iter_impl<typename std::remove_const<BasicJsonType>::type>& other) noexcept + : m_object(other.m_object), m_it(other.m_it) {} + + /*! + @brief converting assignment + @param[in,out] other non-const iterator to copy from + @return const/non-const iterator + @note It is not checked whether @a other is initialized. + */ + iter_impl& operator=(const iter_impl<typename std::remove_const<BasicJsonType>::type>& other) noexcept + { + m_object = other.m_object; + m_it = other.m_it; + return *this; + } + + private: + /*! + @brief set the iterator to the first value + @pre The iterator is initialized; i.e. `m_object != nullptr`. + */ + void set_begin() noexcept + { + assert(m_object != nullptr); + + switch (m_object->m_type) + { + case value_t::object: + { + m_it.object_iterator = m_object->m_value.object->begin(); + break; + } + + case value_t::array: + { + m_it.array_iterator = m_object->m_value.array->begin(); + break; + } + + case value_t::null: + { + // set to end so begin()==end() is true: null is empty + m_it.primitive_iterator.set_end(); + break; + } + + default: + { + m_it.primitive_iterator.set_begin(); + break; + } + } + } + + /*! + @brief set the iterator past the last value + @pre The iterator is initialized; i.e. `m_object != nullptr`. + */ + void set_end() noexcept + { + assert(m_object != nullptr); + + switch (m_object->m_type) + { + case value_t::object: + { + m_it.object_iterator = m_object->m_value.object->end(); + break; + } + + case value_t::array: + { + m_it.array_iterator = m_object->m_value.array->end(); + break; + } + + default: + { + m_it.primitive_iterator.set_end(); + break; + } + } + } + + public: + /*! + @brief return a reference to the value pointed to by the iterator + @pre The iterator is initialized; i.e. `m_object != nullptr`. + */ + reference operator*() const + { + assert(m_object != nullptr); + + switch (m_object->m_type) + { + case value_t::object: + { + assert(m_it.object_iterator != m_object->m_value.object->end()); + return m_it.object_iterator->second; + } + + case value_t::array: + { + assert(m_it.array_iterator != m_object->m_value.array->end()); + return *m_it.array_iterator; + } + + case value_t::null: + JSON_THROW(invalid_iterator::create(214, "cannot get value")); + + default: + { + if (JSON_LIKELY(m_it.primitive_iterator.is_begin())) + { + return *m_object; + } + + JSON_THROW(invalid_iterator::create(214, "cannot get value")); + } + } + } + + /*! + @brief dereference the iterator + @pre The iterator is initialized; i.e. `m_object != nullptr`. + */ + pointer operator->() const + { + assert(m_object != nullptr); + + switch (m_object->m_type) + { + case value_t::object: + { + assert(m_it.object_iterator != m_object->m_value.object->end()); + return &(m_it.object_iterator->second); + } + + case value_t::array: + { + assert(m_it.array_iterator != m_object->m_value.array->end()); + return &*m_it.array_iterator; + } + + default: + { + if (JSON_LIKELY(m_it.primitive_iterator.is_begin())) + { + return m_object; + } + + JSON_THROW(invalid_iterator::create(214, "cannot get value")); + } + } + } + + /*! + @brief post-increment (it++) + @pre The iterator is initialized; i.e. `m_object != nullptr`. + */ + iter_impl const operator++(int) + { + auto result = *this; + ++(*this); + return result; + } + + /*! + @brief pre-increment (++it) + @pre The iterator is initialized; i.e. `m_object != nullptr`. + */ + iter_impl& operator++() + { + assert(m_object != nullptr); + + switch (m_object->m_type) + { + case value_t::object: + { + std::advance(m_it.object_iterator, 1); + break; + } + + case value_t::array: + { + std::advance(m_it.array_iterator, 1); + break; + } + + default: + { + ++m_it.primitive_iterator; + break; + } + } + + return *this; + } + + /*! + @brief post-decrement (it--) + @pre The iterator is initialized; i.e. `m_object != nullptr`. + */ + iter_impl const operator--(int) + { + auto result = *this; + --(*this); + return result; + } + + /*! + @brief pre-decrement (--it) + @pre The iterator is initialized; i.e. `m_object != nullptr`. + */ + iter_impl& operator--() + { + assert(m_object != nullptr); + + switch (m_object->m_type) + { + case value_t::object: + { + std::advance(m_it.object_iterator, -1); + break; + } + + case value_t::array: + { + std::advance(m_it.array_iterator, -1); + break; + } + + default: + { + --m_it.primitive_iterator; + break; + } + } + + return *this; + } + + /*! + @brief comparison: equal + @pre The iterator is initialized; i.e. `m_object != nullptr`. + */ + bool operator==(const iter_impl& other) const + { + // if objects are not the same, the comparison is undefined + if (JSON_UNLIKELY(m_object != other.m_object)) + { + JSON_THROW(invalid_iterator::create(212, "cannot compare iterators of different containers")); + } + + assert(m_object != nullptr); + + switch (m_object->m_type) + { + case value_t::object: + return (m_it.object_iterator == other.m_it.object_iterator); + + case value_t::array: + return (m_it.array_iterator == other.m_it.array_iterator); + + default: + return (m_it.primitive_iterator == other.m_it.primitive_iterator); + } + } + + /*! + @brief comparison: not equal + @pre The iterator is initialized; i.e. `m_object != nullptr`. + */ + bool operator!=(const iter_impl& other) const + { + return not operator==(other); + } + + /*! + @brief comparison: smaller + @pre The iterator is initialized; i.e. `m_object != nullptr`. + */ + bool operator<(const iter_impl& other) const + { + // if objects are not the same, the comparison is undefined + if (JSON_UNLIKELY(m_object != other.m_object)) + { + JSON_THROW(invalid_iterator::create(212, "cannot compare iterators of different containers")); + } + + assert(m_object != nullptr); + + switch (m_object->m_type) + { + case value_t::object: + JSON_THROW(invalid_iterator::create(213, "cannot compare order of object iterators")); + + case value_t::array: + return (m_it.array_iterator < other.m_it.array_iterator); + + default: + return (m_it.primitive_iterator < other.m_it.primitive_iterator); + } + } + + /*! + @brief comparison: less than or equal + @pre The iterator is initialized; i.e. `m_object != nullptr`. + */ + bool operator<=(const iter_impl& other) const + { + return not other.operator < (*this); + } + + /*! + @brief comparison: greater than + @pre The iterator is initialized; i.e. `m_object != nullptr`. + */ + bool operator>(const iter_impl& other) const + { + return not operator<=(other); + } + + /*! + @brief comparison: greater than or equal + @pre The iterator is initialized; i.e. `m_object != nullptr`. + */ + bool operator>=(const iter_impl& other) const + { + return not operator<(other); + } + + /*! + @brief add to iterator + @pre The iterator is initialized; i.e. `m_object != nullptr`. + */ + iter_impl& operator+=(difference_type i) + { + assert(m_object != nullptr); + + switch (m_object->m_type) + { + case value_t::object: + JSON_THROW(invalid_iterator::create(209, "cannot use offsets with object iterators")); + + case value_t::array: + { + std::advance(m_it.array_iterator, i); + break; + } + + default: + { + m_it.primitive_iterator += i; + break; + } + } + + return *this; + } + + /*! + @brief subtract from iterator + @pre The iterator is initialized; i.e. `m_object != nullptr`. + */ + iter_impl& operator-=(difference_type i) + { + return operator+=(-i); + } + + /*! + @brief add to iterator + @pre The iterator is initialized; i.e. `m_object != nullptr`. + */ + iter_impl operator+(difference_type i) const + { + auto result = *this; + result += i; + return result; + } + + /*! + @brief addition of distance and iterator + @pre The iterator is initialized; i.e. `m_object != nullptr`. + */ + friend iter_impl operator+(difference_type i, const iter_impl& it) + { + auto result = it; + result += i; + return result; + } + + /*! + @brief subtract from iterator + @pre The iterator is initialized; i.e. `m_object != nullptr`. + */ + iter_impl operator-(difference_type i) const + { + auto result = *this; + result -= i; + return result; + } + + /*! + @brief return difference + @pre The iterator is initialized; i.e. `m_object != nullptr`. + */ + difference_type operator-(const iter_impl& other) const + { + assert(m_object != nullptr); + + switch (m_object->m_type) + { + case value_t::object: + JSON_THROW(invalid_iterator::create(209, "cannot use offsets with object iterators")); + + case value_t::array: + return m_it.array_iterator - other.m_it.array_iterator; + + default: + return m_it.primitive_iterator - other.m_it.primitive_iterator; + } + } + + /*! + @brief access to successor + @pre The iterator is initialized; i.e. `m_object != nullptr`. + */ + reference operator[](difference_type n) const + { + assert(m_object != nullptr); + + switch (m_object->m_type) + { + case value_t::object: + JSON_THROW(invalid_iterator::create(208, "cannot use operator[] for object iterators")); + + case value_t::array: + return *std::next(m_it.array_iterator, n); + + case value_t::null: + JSON_THROW(invalid_iterator::create(214, "cannot get value")); + + default: + { + if (JSON_LIKELY(m_it.primitive_iterator.get_value() == -n)) + { + return *m_object; + } + + JSON_THROW(invalid_iterator::create(214, "cannot get value")); + } + } + } + + /*! + @brief return the key of an object iterator + @pre The iterator is initialized; i.e. `m_object != nullptr`. + */ + typename object_t::key_type key() const + { + assert(m_object != nullptr); + + if (JSON_LIKELY(m_object->is_object())) + { + return m_it.object_iterator->first; + } + + JSON_THROW(invalid_iterator::create(207, "cannot use key() for non-object iterators")); + } + + /*! + @brief return the value of an iterator + @pre The iterator is initialized; i.e. `m_object != nullptr`. + */ + reference value() const + { + return operator*(); + } + + private: + /// associated JSON instance + pointer m_object = nullptr; + /// the actual iterator of the associated instance + internal_iterator<typename std::remove_const<BasicJsonType>::type> m_it = {}; +}; + +/// proxy class for the iterator_wrapper functions +template<typename IteratorType> class iteration_proxy +{ + private: + /// helper class for iteration + class iteration_proxy_internal + { + private: + /// the iterator + IteratorType anchor; + /// an index for arrays (used to create key names) + std::size_t array_index = 0; + + public: + explicit iteration_proxy_internal(IteratorType it) noexcept : anchor(it) {} + + /// dereference operator (needed for range-based for) + iteration_proxy_internal& operator*() + { + return *this; + } + + /// increment operator (needed for range-based for) + iteration_proxy_internal& operator++() + { + ++anchor; + ++array_index; + + return *this; + } + + /// inequality operator (needed for range-based for) + bool operator!=(const iteration_proxy_internal& o) const noexcept + { + return anchor != o.anchor; + } + + /// return key of the iterator + std::string key() const + { + assert(anchor.m_object != nullptr); + + switch (anchor.m_object->type()) + { + // use integer array index as key + case value_t::array: + return std::to_string(array_index); + + // use key from the object + case value_t::object: + return anchor.key(); + + // use an empty key for all primitive types + default: + return ""; + } + } + + /// return value of the iterator + typename IteratorType::reference value() const + { + return anchor.value(); + } + }; + + /// the container to iterate + typename IteratorType::reference container; + + public: + /// construct iteration proxy from a container + explicit iteration_proxy(typename IteratorType::reference cont) + : container(cont) {} + + /// return iterator begin (needed for range-based for) + iteration_proxy_internal begin() noexcept + { + return iteration_proxy_internal(container.begin()); + } + + /// return iterator end (needed for range-based for) + iteration_proxy_internal end() noexcept + { + return iteration_proxy_internal(container.end()); + } +}; + +/*! +@brief a template for a reverse iterator class + +@tparam Base the base iterator type to reverse. Valid types are @ref +iterator (to create @ref reverse_iterator) and @ref const_iterator (to +create @ref const_reverse_iterator). + +@requirement The class satisfies the following concept requirements: +- +[BidirectionalIterator](http://en.cppreference.com/w/cpp/concept/BidirectionalIterator): + The iterator that can be moved can be moved in both directions (i.e. + incremented and decremented). +- [OutputIterator](http://en.cppreference.com/w/cpp/concept/OutputIterator): + It is possible to write to the pointed-to element (only if @a Base is + @ref iterator). + +@since version 1.0.0 +*/ +template<typename Base> +class json_reverse_iterator : public std::reverse_iterator<Base> +{ + public: + using difference_type = std::ptrdiff_t; + /// shortcut to the reverse iterator adapter + using base_iterator = std::reverse_iterator<Base>; + /// the reference type for the pointed-to element + using reference = typename Base::reference; + + /// create reverse iterator from iterator + json_reverse_iterator(const typename base_iterator::iterator_type& it) noexcept + : base_iterator(it) {} + + /// create reverse iterator from base class + json_reverse_iterator(const base_iterator& it) noexcept : base_iterator(it) {} + + /// post-increment (it++) + json_reverse_iterator const operator++(int) + { + return static_cast<json_reverse_iterator>(base_iterator::operator++(1)); + } + + /// pre-increment (++it) + json_reverse_iterator& operator++() + { + return static_cast<json_reverse_iterator&>(base_iterator::operator++()); + } + + /// post-decrement (it--) + json_reverse_iterator const operator--(int) + { + return static_cast<json_reverse_iterator>(base_iterator::operator--(1)); + } + + /// pre-decrement (--it) + json_reverse_iterator& operator--() + { + return static_cast<json_reverse_iterator&>(base_iterator::operator--()); + } + + /// add to iterator + json_reverse_iterator& operator+=(difference_type i) + { + return static_cast<json_reverse_iterator&>(base_iterator::operator+=(i)); + } + + /// add to iterator + json_reverse_iterator operator+(difference_type i) const + { + return static_cast<json_reverse_iterator>(base_iterator::operator+(i)); + } + + /// subtract from iterator + json_reverse_iterator operator-(difference_type i) const + { + return static_cast<json_reverse_iterator>(base_iterator::operator-(i)); + } + + /// return difference + difference_type operator-(const json_reverse_iterator& other) const + { + return base_iterator(*this) - base_iterator(other); + } + + /// access to successor + reference operator[](difference_type n) const + { + return *(this->operator+(n)); + } + + /// return the key of an object iterator + auto key() const -> decltype(std::declval<Base>().key()) + { + auto it = --this->base(); + return it.key(); + } + + /// return the value of an iterator + reference value() const + { + auto it = --this->base(); + return it.operator * (); + } +}; + +///////////////////// +// output adapters // +///////////////////// + +/// abstract output adapter interface +template<typename CharType> struct output_adapter_protocol +{ + virtual void write_character(CharType c) = 0; + virtual void write_characters(const CharType* s, std::size_t length) = 0; + virtual ~output_adapter_protocol() = default; +}; + +/// a type to simplify interfaces +template<typename CharType> +using output_adapter_t = std::shared_ptr<output_adapter_protocol<CharType>>; + +/// output adapter for byte vectors +template<typename CharType> +class output_vector_adapter : public output_adapter_protocol<CharType> +{ + public: + explicit output_vector_adapter(std::vector<CharType>& vec) : v(vec) {} + + void write_character(CharType c) override + { + v.push_back(c); + } + + void write_characters(const CharType* s, std::size_t length) override + { + std::copy(s, s + length, std::back_inserter(v)); + } + + private: + std::vector<CharType>& v; +}; + +/// output adapter for output streams +template<typename CharType> +class output_stream_adapter : public output_adapter_protocol<CharType> +{ + public: + explicit output_stream_adapter(std::basic_ostream<CharType>& s) : stream(s) {} + + void write_character(CharType c) override + { + stream.put(c); + } + + void write_characters(const CharType* s, std::size_t length) override + { + stream.write(s, static_cast<std::streamsize>(length)); + } + + private: + std::basic_ostream<CharType>& stream; +}; + +/// output adapter for basic_string +template<typename CharType> +class output_string_adapter : public output_adapter_protocol<CharType> +{ + public: + explicit output_string_adapter(std::basic_string<CharType>& s) : str(s) {} + + void write_character(CharType c) override + { + str.push_back(c); + } + + void write_characters(const CharType* s, std::size_t length) override + { + str.append(s, length); + } + + private: + std::basic_string<CharType>& str; +}; + +template<typename CharType> +class output_adapter +{ + public: + output_adapter(std::vector<CharType>& vec) + : oa(std::make_shared<output_vector_adapter<CharType>>(vec)) {} + + output_adapter(std::basic_ostream<CharType>& s) + : oa(std::make_shared<output_stream_adapter<CharType>>(s)) {} + + output_adapter(std::basic_string<CharType>& s) + : oa(std::make_shared<output_string_adapter<CharType>>(s)) {} + + operator output_adapter_t<CharType>() + { + return oa; + } + + private: + output_adapter_t<CharType> oa = nullptr; +}; + +////////////////////////////// +// binary reader and writer // +////////////////////////////// + +/*! +@brief deserialization of CBOR and MessagePack values +*/ +template<typename BasicJsonType> +class binary_reader +{ + using number_integer_t = typename BasicJsonType::number_integer_t; + using number_unsigned_t = typename BasicJsonType::number_unsigned_t; + + public: + /*! + @brief create a binary reader + + @param[in] adapter input adapter to read from + */ + explicit binary_reader(input_adapter_t adapter) : ia(std::move(adapter)) + { + assert(ia); + } + + /*! + @brief create a JSON value from CBOR input + + @param[in] strict whether to expect the input to be consumed completed + @return JSON value created from CBOR input + + @throw parse_error.110 if input ended unexpectedly or the end of file was + not reached when @a strict was set to true + @throw parse_error.112 if unsupported byte was read + */ + BasicJsonType parse_cbor(const bool strict) + { + const auto res = parse_cbor_internal(); + if (strict) + { + get(); + check_eof(true); + } + return res; + } + + /*! + @brief create a JSON value from MessagePack input + + @param[in] strict whether to expect the input to be consumed completed + @return JSON value created from MessagePack input + + @throw parse_error.110 if input ended unexpectedly or the end of file was + not reached when @a strict was set to true + @throw parse_error.112 if unsupported byte was read + */ + BasicJsonType parse_msgpack(const bool strict) + { + const auto res = parse_msgpack_internal(); + if (strict) + { + get(); + check_eof(true); + } + return res; + } + + /*! + @brief determine system byte order + + @return true if and only if system's byte order is little endian + + @note from http://stackoverflow.com/a/1001328/266378 + */ + static constexpr bool little_endianess(int num = 1) noexcept + { + return (*reinterpret_cast<char*>(&num) == 1); + } + + private: + /*! + @param[in] get_char whether a new character should be retrieved from the + input (true, default) or whether the last read + character should be considered instead + */ + BasicJsonType parse_cbor_internal(const bool get_char = true) + { + switch (get_char ? get() : current) + { + // EOF + case std::char_traits<char>::eof(): + JSON_THROW(parse_error::create(110, chars_read, "unexpected end of input")); + + // Integer 0x00..0x17 (0..23) + case 0x00: + case 0x01: + case 0x02: + case 0x03: + case 0x04: + case 0x05: + case 0x06: + case 0x07: + case 0x08: + case 0x09: + case 0x0A: + case 0x0B: + case 0x0C: + case 0x0D: + case 0x0E: + case 0x0F: + case 0x10: + case 0x11: + case 0x12: + case 0x13: + case 0x14: + case 0x15: + case 0x16: + case 0x17: + return static_cast<number_unsigned_t>(current); + + case 0x18: // Unsigned integer (one-byte uint8_t follows) + return get_number<uint8_t>(); + + case 0x19: // Unsigned integer (two-byte uint16_t follows) + return get_number<uint16_t>(); + + case 0x1A: // Unsigned integer (four-byte uint32_t follows) + return get_number<uint32_t>(); + + case 0x1B: // Unsigned integer (eight-byte uint64_t follows) + return get_number<uint64_t>(); + + // Negative integer -1-0x00..-1-0x17 (-1..-24) + case 0x20: + case 0x21: + case 0x22: + case 0x23: + case 0x24: + case 0x25: + case 0x26: + case 0x27: + case 0x28: + case 0x29: + case 0x2A: + case 0x2B: + case 0x2C: + case 0x2D: + case 0x2E: + case 0x2F: + case 0x30: + case 0x31: + case 0x32: + case 0x33: + case 0x34: + case 0x35: + case 0x36: + case 0x37: + return static_cast<int8_t>(0x20 - 1 - current); + + case 0x38: // Negative integer (one-byte uint8_t follows) + { + // must be uint8_t ! + return static_cast<number_integer_t>(-1) - get_number<uint8_t>(); + } + + case 0x39: // Negative integer -1-n (two-byte uint16_t follows) + { + return static_cast<number_integer_t>(-1) - get_number<uint16_t>(); + } + + case 0x3A: // Negative integer -1-n (four-byte uint32_t follows) + { + return static_cast<number_integer_t>(-1) - get_number<uint32_t>(); + } + + case 0x3B: // Negative integer -1-n (eight-byte uint64_t follows) + { + return static_cast<number_integer_t>(-1) - + static_cast<number_integer_t>(get_number<uint64_t>()); + } + + // UTF-8 string (0x00..0x17 bytes follow) + case 0x60: + case 0x61: + case 0x62: + case 0x63: + case 0x64: + case 0x65: + case 0x66: + case 0x67: + case 0x68: + case 0x69: + case 0x6A: + case 0x6B: + case 0x6C: + case 0x6D: + case 0x6E: + case 0x6F: + case 0x70: + case 0x71: + case 0x72: + case 0x73: + case 0x74: + case 0x75: + case 0x76: + case 0x77: + case 0x78: // UTF-8 string (one-byte uint8_t for n follows) + case 0x79: // UTF-8 string (two-byte uint16_t for n follow) + case 0x7A: // UTF-8 string (four-byte uint32_t for n follow) + case 0x7B: // UTF-8 string (eight-byte uint64_t for n follow) + case 0x7F: // UTF-8 string (indefinite length) + { + return get_cbor_string(); + } + + // array (0x00..0x17 data items follow) + case 0x80: + case 0x81: + case 0x82: + case 0x83: + case 0x84: + case 0x85: + case 0x86: + case 0x87: + case 0x88: + case 0x89: + case 0x8A: + case 0x8B: + case 0x8C: + case 0x8D: + case 0x8E: + case 0x8F: + case 0x90: + case 0x91: + case 0x92: + case 0x93: + case 0x94: + case 0x95: + case 0x96: + case 0x97: + { + return get_cbor_array(current & 0x1F); + } + + case 0x98: // array (one-byte uint8_t for n follows) + { + return get_cbor_array(get_number<uint8_t>()); + } + + case 0x99: // array (two-byte uint16_t for n follow) + { + return get_cbor_array(get_number<uint16_t>()); + } + + case 0x9A: // array (four-byte uint32_t for n follow) + { + return get_cbor_array(get_number<uint32_t>()); + } + + case 0x9B: // array (eight-byte uint64_t for n follow) + { + return get_cbor_array(get_number<uint64_t>()); + } + + case 0x9F: // array (indefinite length) + { + BasicJsonType result = value_t::array; + while (get() != 0xFF) + { + result.push_back(parse_cbor_internal(false)); + } + return result; + } + + // map (0x00..0x17 pairs of data items follow) + case 0xA0: + case 0xA1: + case 0xA2: + case 0xA3: + case 0xA4: + case 0xA5: + case 0xA6: + case 0xA7: + case 0xA8: + case 0xA9: + case 0xAA: + case 0xAB: + case 0xAC: + case 0xAD: + case 0xAE: + case 0xAF: + case 0xB0: + case 0xB1: + case 0xB2: + case 0xB3: + case 0xB4: + case 0xB5: + case 0xB6: + case 0xB7: + { + return get_cbor_object(current & 0x1F); + } + + case 0xB8: // map (one-byte uint8_t for n follows) + { + return get_cbor_object(get_number<uint8_t>()); + } + + case 0xB9: // map (two-byte uint16_t for n follow) + { + return get_cbor_object(get_number<uint16_t>()); + } + + case 0xBA: // map (four-byte uint32_t for n follow) + { + return get_cbor_object(get_number<uint32_t>()); + } + + case 0xBB: // map (eight-byte uint64_t for n follow) + { + return get_cbor_object(get_number<uint64_t>()); + } + + case 0xBF: // map (indefinite length) + { + BasicJsonType result = value_t::object; + while (get() != 0xFF) + { + auto key = get_cbor_string(); + result[key] = parse_cbor_internal(); + } + return result; + } + + case 0xF4: // false + { + return false; + } + + case 0xF5: // true + { + return true; + } + + case 0xF6: // null + { + return value_t::null; + } + + case 0xF9: // Half-Precision Float (two-byte IEEE 754) + { + const int byte1 = get(); + check_eof(); + const int byte2 = get(); + check_eof(); + + // code from RFC 7049, Appendix D, Figure 3: + // As half-precision floating-point numbers were only added + // to IEEE 754 in 2008, today's programming platforms often + // still only have limited support for them. It is very + // easy to include at least decoding support for them even + // without such support. An example of a small decoder for + // half-precision floating-point numbers in the C language + // is shown in Fig. 3. + const int half = (byte1 << 8) + byte2; + const int exp = (half >> 10) & 0x1F; + const int mant = half & 0x3FF; + double val; + if (exp == 0) + { + val = std::ldexp(mant, -24); + } + else if (exp != 31) + { + val = std::ldexp(mant + 1024, exp - 25); + } + else + { + val = (mant == 0) ? std::numeric_limits<double>::infinity() + : std::numeric_limits<double>::quiet_NaN(); + } + return (half & 0x8000) != 0 ? -val : val; + } + + case 0xFA: // Single-Precision Float (four-byte IEEE 754) + { + return get_number<float>(); + } + + case 0xFB: // Double-Precision Float (eight-byte IEEE 754) + { + return get_number<double>(); + } + + default: // anything else (0xFF is handled inside the other types) + { + std::stringstream ss; + ss << std::setw(2) << std::uppercase << std::setfill('0') << std::hex << current; + JSON_THROW(parse_error::create(112, chars_read, "error reading CBOR; last byte: 0x" + ss.str())); + } + } + } + + BasicJsonType parse_msgpack_internal() + { + switch (get()) + { + // EOF + case std::char_traits<char>::eof(): + JSON_THROW(parse_error::create(110, chars_read, "unexpected end of input")); + + // positive fixint + case 0x00: + case 0x01: + case 0x02: + case 0x03: + case 0x04: + case 0x05: + case 0x06: + case 0x07: + case 0x08: + case 0x09: + case 0x0A: + case 0x0B: + case 0x0C: + case 0x0D: + case 0x0E: + case 0x0F: + case 0x10: + case 0x11: + case 0x12: + case 0x13: + case 0x14: + case 0x15: + case 0x16: + case 0x17: + case 0x18: + case 0x19: + case 0x1A: + case 0x1B: + case 0x1C: + case 0x1D: + case 0x1E: + case 0x1F: + case 0x20: + case 0x21: + case 0x22: + case 0x23: + case 0x24: + case 0x25: + case 0x26: + case 0x27: + case 0x28: + case 0x29: + case 0x2A: + case 0x2B: + case 0x2C: + case 0x2D: + case 0x2E: + case 0x2F: + case 0x30: + case 0x31: + case 0x32: + case 0x33: + case 0x34: + case 0x35: + case 0x36: + case 0x37: + case 0x38: + case 0x39: + case 0x3A: + case 0x3B: + case 0x3C: + case 0x3D: + case 0x3E: + case 0x3F: + case 0x40: + case 0x41: + case 0x42: + case 0x43: + case 0x44: + case 0x45: + case 0x46: + case 0x47: + case 0x48: + case 0x49: + case 0x4A: + case 0x4B: + case 0x4C: + case 0x4D: + case 0x4E: + case 0x4F: + case 0x50: + case 0x51: + case 0x52: + case 0x53: + case 0x54: + case 0x55: + case 0x56: + case 0x57: + case 0x58: + case 0x59: + case 0x5A: + case 0x5B: + case 0x5C: + case 0x5D: + case 0x5E: + case 0x5F: + case 0x60: + case 0x61: + case 0x62: + case 0x63: + case 0x64: + case 0x65: + case 0x66: + case 0x67: + case 0x68: + case 0x69: + case 0x6A: + case 0x6B: + case 0x6C: + case 0x6D: + case 0x6E: + case 0x6F: + case 0x70: + case 0x71: + case 0x72: + case 0x73: + case 0x74: + case 0x75: + case 0x76: + case 0x77: + case 0x78: + case 0x79: + case 0x7A: + case 0x7B: + case 0x7C: + case 0x7D: + case 0x7E: + case 0x7F: + return static_cast<number_unsigned_t>(current); + + // fixmap + case 0x80: + case 0x81: + case 0x82: + case 0x83: + case 0x84: + case 0x85: + case 0x86: + case 0x87: + case 0x88: + case 0x89: + case 0x8A: + case 0x8B: + case 0x8C: + case 0x8D: + case 0x8E: + case 0x8F: + { + return get_msgpack_object(current & 0x0F); + } + + // fixarray + case 0x90: + case 0x91: + case 0x92: + case 0x93: + case 0x94: + case 0x95: + case 0x96: + case 0x97: + case 0x98: + case 0x99: + case 0x9A: + case 0x9B: + case 0x9C: + case 0x9D: + case 0x9E: + case 0x9F: + { + return get_msgpack_array(current & 0x0F); + } + + // fixstr + case 0xA0: + case 0xA1: + case 0xA2: + case 0xA3: + case 0xA4: + case 0xA5: + case 0xA6: + case 0xA7: + case 0xA8: + case 0xA9: + case 0xAA: + case 0xAB: + case 0xAC: + case 0xAD: + case 0xAE: + case 0xAF: + case 0xB0: + case 0xB1: + case 0xB2: + case 0xB3: + case 0xB4: + case 0xB5: + case 0xB6: + case 0xB7: + case 0xB8: + case 0xB9: + case 0xBA: + case 0xBB: + case 0xBC: + case 0xBD: + case 0xBE: + case 0xBF: + return get_msgpack_string(); + + case 0xC0: // nil + return value_t::null; + + case 0xC2: // false + return false; + + case 0xC3: // true + return true; + + case 0xCA: // float 32 + return get_number<float>(); + + case 0xCB: // float 64 + return get_number<double>(); + + case 0xCC: // uint 8 + return get_number<uint8_t>(); + + case 0xCD: // uint 16 + return get_number<uint16_t>(); + + case 0xCE: // uint 32 + return get_number<uint32_t>(); + + case 0xCF: // uint 64 + return get_number<uint64_t>(); + + case 0xD0: // int 8 + return get_number<int8_t>(); + + case 0xD1: // int 16 + return get_number<int16_t>(); + + case 0xD2: // int 32 + return get_number<int32_t>(); + + case 0xD3: // int 64 + return get_number<int64_t>(); + + case 0xD9: // str 8 + case 0xDA: // str 16 + case 0xDB: // str 32 + return get_msgpack_string(); + + case 0xDC: // array 16 + { + return get_msgpack_array(get_number<uint16_t>()); + } + + case 0xDD: // array 32 + { + return get_msgpack_array(get_number<uint32_t>()); + } + + case 0xDE: // map 16 + { + return get_msgpack_object(get_number<uint16_t>()); + } + + case 0xDF: // map 32 + { + return get_msgpack_object(get_number<uint32_t>()); + } + + // positive fixint + case 0xE0: + case 0xE1: + case 0xE2: + case 0xE3: + case 0xE4: + case 0xE5: + case 0xE6: + case 0xE7: + case 0xE8: + case 0xE9: + case 0xEA: + case 0xEB: + case 0xEC: + case 0xED: + case 0xEE: + case 0xEF: + case 0xF0: + case 0xF1: + case 0xF2: + case 0xF3: + case 0xF4: + case 0xF5: + case 0xF6: + case 0xF7: + case 0xF8: + case 0xF9: + case 0xFA: + case 0xFB: + case 0xFC: + case 0xFD: + case 0xFE: + case 0xFF: + return static_cast<int8_t>(current); + + default: // anything else + { + std::stringstream ss; + ss << std::setw(2) << std::uppercase << std::setfill('0') << std::hex << current; + JSON_THROW(parse_error::create(112, chars_read, + "error reading MessagePack; last byte: 0x" + ss.str())); + } + } + } + + /*! + @brief get next character from the input + + This function provides the interface to the used input adapter. It does + not throw in case the input reached EOF, but returns a -'ve valued + `std::char_traits<char>::eof()` in that case. + + @return character read from the input + */ + int get() + { + ++chars_read; + return (current = ia->get_character()); + } + + /* + @brief read a number from the input + + @tparam NumberType the type of the number + + @return number of type @a NumberType + + @note This function needs to respect the system's endianess, because + bytes in CBOR and MessagePack are stored in network order (big + endian) and therefore need reordering on little endian systems. + + @throw parse_error.110 if input has less than `sizeof(NumberType)` bytes + */ + template<typename NumberType> NumberType get_number() + { + // step 1: read input into array with system's byte order + std::array<uint8_t, sizeof(NumberType)> vec; + for (std::size_t i = 0; i < sizeof(NumberType); ++i) + { + get(); + check_eof(); + + // reverse byte order prior to conversion if necessary + if (is_little_endian) + { + vec[sizeof(NumberType) - i - 1] = static_cast<uint8_t>(current); + } + else + { + vec[i] = static_cast<uint8_t>(current); // LCOV_EXCL_LINE + } + } + + // step 2: convert array into number of type T and return + NumberType result; + std::memcpy(&result, vec.data(), sizeof(NumberType)); + return result; + } + + /*! + @brief create a string by reading characters from the input + + @param[in] len number of bytes to read + + @note We can not reserve @a len bytes for the result, because @a len + may be too large. Usually, @ref check_eof() detects the end of + the input before we run out of string memory. + + @return string created by reading @a len bytes + + @throw parse_error.110 if input has less than @a len bytes + */ + template<typename NumberType> + std::string get_string(const NumberType len) + { + std::string result; + std::generate_n(std::back_inserter(result), len, [this]() + { + get(); + check_eof(); + return static_cast<char>(current); + }); + return result; + } + + /*! + @brief reads a CBOR string + + This function first reads starting bytes to determine the expected + string length and then copies this number of bytes into a string. + Additionally, CBOR's strings with indefinite lengths are supported. + + @return string + + @throw parse_error.110 if input ended + @throw parse_error.113 if an unexpected byte is read + */ + std::string get_cbor_string() + { + check_eof(); + + switch (current) + { + // UTF-8 string (0x00..0x17 bytes follow) + case 0x60: + case 0x61: + case 0x62: + case 0x63: + case 0x64: + case 0x65: + case 0x66: + case 0x67: + case 0x68: + case 0x69: + case 0x6A: + case 0x6B: + case 0x6C: + case 0x6D: + case 0x6E: + case 0x6F: + case 0x70: + case 0x71: + case 0x72: + case 0x73: + case 0x74: + case 0x75: + case 0x76: + case 0x77: + { + return get_string(current & 0x1F); + } + + case 0x78: // UTF-8 string (one-byte uint8_t for n follows) + { + return get_string(get_number<uint8_t>()); + } + + case 0x79: // UTF-8 string (two-byte uint16_t for n follow) + { + return get_string(get_number<uint16_t>()); + } + + case 0x7A: // UTF-8 string (four-byte uint32_t for n follow) + { + return get_string(get_number<uint32_t>()); + } + + case 0x7B: // UTF-8 string (eight-byte uint64_t for n follow) + { + return get_string(get_number<uint64_t>()); + } + + case 0x7F: // UTF-8 string (indefinite length) + { + std::string result; + while (get() != 0xFF) + { + check_eof(); + result.push_back(static_cast<char>(current)); + } + return result; + } + + default: + { + std::stringstream ss; + ss << std::setw(2) << std::uppercase << std::setfill('0') << std::hex << current; + JSON_THROW(parse_error::create(113, chars_read, "expected a CBOR string; last byte: 0x" + ss.str())); + } + } + } + + template<typename NumberType> + BasicJsonType get_cbor_array(const NumberType len) + { + BasicJsonType result = value_t::array; + std::generate_n(std::back_inserter(*result.m_value.array), len, [this]() + { + return parse_cbor_internal(); + }); + return result; + } + + template<typename NumberType> + BasicJsonType get_cbor_object(const NumberType len) + { + BasicJsonType result = value_t::object; + std::generate_n(std::inserter(*result.m_value.object, + result.m_value.object->end()), + len, [this]() + { + get(); + auto key = get_cbor_string(); + auto val = parse_cbor_internal(); + return std::make_pair(std::move(key), std::move(val)); + }); + return result; + } + + /*! + @brief reads a MessagePack string + + This function first reads starting bytes to determine the expected + string length and then copies this number of bytes into a string. + + @return string + + @throw parse_error.110 if input ended + @throw parse_error.113 if an unexpected byte is read + */ + std::string get_msgpack_string() + { + check_eof(); + + switch (current) + { + // fixstr + case 0xA0: + case 0xA1: + case 0xA2: + case 0xA3: + case 0xA4: + case 0xA5: + case 0xA6: + case 0xA7: + case 0xA8: + case 0xA9: + case 0xAA: + case 0xAB: + case 0xAC: + case 0xAD: + case 0xAE: + case 0xAF: + case 0xB0: + case 0xB1: + case 0xB2: + case 0xB3: + case 0xB4: + case 0xB5: + case 0xB6: + case 0xB7: + case 0xB8: + case 0xB9: + case 0xBA: + case 0xBB: + case 0xBC: + case 0xBD: + case 0xBE: + case 0xBF: + { + return get_string(current & 0x1F); + } + + case 0xD9: // str 8 + { + return get_string(get_number<uint8_t>()); + } + + case 0xDA: // str 16 + { + return get_string(get_number<uint16_t>()); + } + + case 0xDB: // str 32 + { + return get_string(get_number<uint32_t>()); + } + + default: + { + std::stringstream ss; + ss << std::setw(2) << std::uppercase << std::setfill('0') << std::hex << current; + JSON_THROW(parse_error::create(113, chars_read, + "expected a MessagePack string; last byte: 0x" + ss.str())); + } + } + } + + template<typename NumberType> + BasicJsonType get_msgpack_array(const NumberType len) + { + BasicJsonType result = value_t::array; + std::generate_n(std::back_inserter(*result.m_value.array), len, [this]() + { + return parse_msgpack_internal(); + }); + return result; + } + + template<typename NumberType> + BasicJsonType get_msgpack_object(const NumberType len) + { + BasicJsonType result = value_t::object; + std::generate_n(std::inserter(*result.m_value.object, + result.m_value.object->end()), + len, [this]() + { + get(); + auto key = get_msgpack_string(); + auto val = parse_msgpack_internal(); + return std::make_pair(std::move(key), std::move(val)); + }); + return result; + } + + /*! + @brief check if input ended + @throw parse_error.110 if input ended + */ + void check_eof(const bool expect_eof = false) const + { + if (expect_eof) + { + if (JSON_UNLIKELY(current != std::char_traits<char>::eof())) + { + JSON_THROW(parse_error::create(110, chars_read, "expected end of input")); + } + } + else + { + if (JSON_UNLIKELY(current == std::char_traits<char>::eof())) + { + JSON_THROW(parse_error::create(110, chars_read, "unexpected end of input")); + } + } + } + + private: + /// input adapter + input_adapter_t ia = nullptr; + + /// the current character + int current = std::char_traits<char>::eof(); + + /// the number of characters read + std::size_t chars_read = 0; + + /// whether we can assume little endianess + const bool is_little_endian = little_endianess(); +}; + +/*! +@brief serialization to CBOR and MessagePack values +*/ +template<typename BasicJsonType, typename CharType> +class binary_writer +{ + public: + /*! + @brief create a binary writer + + @param[in] adapter output adapter to write to + */ + explicit binary_writer(output_adapter_t<CharType> adapter) : oa(adapter) + { + assert(oa); + } + + /*! + @brief[in] j JSON value to serialize + */ + void write_cbor(const BasicJsonType& j) + { + switch (j.type()) + { + case value_t::null: + { + oa->write_character(static_cast<CharType>(0xF6)); + break; + } + + case value_t::boolean: + { + oa->write_character(j.m_value.boolean + ? static_cast<CharType>(0xF5) + : static_cast<CharType>(0xF4)); + break; + } + + case value_t::number_integer: + { + if (j.m_value.number_integer >= 0) + { + // CBOR does not differentiate between positive signed + // integers and unsigned integers. Therefore, we used the + // code from the value_t::number_unsigned case here. + if (j.m_value.number_integer <= 0x17) + { + write_number(static_cast<uint8_t>(j.m_value.number_integer)); + } + else if (j.m_value.number_integer <= (std::numeric_limits<uint8_t>::max)()) + { + oa->write_character(static_cast<CharType>(0x18)); + write_number(static_cast<uint8_t>(j.m_value.number_integer)); + } + else if (j.m_value.number_integer <= (std::numeric_limits<uint16_t>::max)()) + { + oa->write_character(static_cast<CharType>(0x19)); + write_number(static_cast<uint16_t>(j.m_value.number_integer)); + } + else if (j.m_value.number_integer <= (std::numeric_limits<uint32_t>::max)()) + { + oa->write_character(static_cast<CharType>(0x1A)); + write_number(static_cast<uint32_t>(j.m_value.number_integer)); + } + else + { + oa->write_character(static_cast<CharType>(0x1B)); + write_number(static_cast<uint64_t>(j.m_value.number_integer)); + } + } + else + { + // The conversions below encode the sign in the first + // byte, and the value is converted to a positive number. + const auto positive_number = -1 - j.m_value.number_integer; + if (j.m_value.number_integer >= -24) + { + write_number(static_cast<uint8_t>(0x20 + positive_number)); + } + else if (positive_number <= (std::numeric_limits<uint8_t>::max)()) + { + oa->write_character(static_cast<CharType>(0x38)); + write_number(static_cast<uint8_t>(positive_number)); + } + else if (positive_number <= (std::numeric_limits<uint16_t>::max)()) + { + oa->write_character(static_cast<CharType>(0x39)); + write_number(static_cast<uint16_t>(positive_number)); + } + else if (positive_number <= (std::numeric_limits<uint32_t>::max)()) + { + oa->write_character(static_cast<CharType>(0x3A)); + write_number(static_cast<uint32_t>(positive_number)); + } + else + { + oa->write_character(static_cast<CharType>(0x3B)); + write_number(static_cast<uint64_t>(positive_number)); + } + } + break; + } + + case value_t::number_unsigned: + { + if (j.m_value.number_unsigned <= 0x17) + { + write_number(static_cast<uint8_t>(j.m_value.number_unsigned)); + } + else if (j.m_value.number_unsigned <= (std::numeric_limits<uint8_t>::max)()) + { + oa->write_character(static_cast<CharType>(0x18)); + write_number(static_cast<uint8_t>(j.m_value.number_unsigned)); + } + else if (j.m_value.number_unsigned <= (std::numeric_limits<uint16_t>::max)()) + { + oa->write_character(static_cast<CharType>(0x19)); + write_number(static_cast<uint16_t>(j.m_value.number_unsigned)); + } + else if (j.m_value.number_unsigned <= (std::numeric_limits<uint32_t>::max)()) + { + oa->write_character(static_cast<CharType>(0x1A)); + write_number(static_cast<uint32_t>(j.m_value.number_unsigned)); + } + else + { + oa->write_character(static_cast<CharType>(0x1B)); + write_number(static_cast<uint64_t>(j.m_value.number_unsigned)); + } + break; + } + + case value_t::number_float: // Double-Precision Float + { + oa->write_character(static_cast<CharType>(0xFB)); + write_number(j.m_value.number_float); + break; + } + + case value_t::string: + { + // step 1: write control byte and the string length + const auto N = j.m_value.string->size(); + if (N <= 0x17) + { + write_number(static_cast<uint8_t>(0x60 + N)); + } + else if (N <= 0xFF) + { + oa->write_character(static_cast<CharType>(0x78)); + write_number(static_cast<uint8_t>(N)); + } + else if (N <= 0xFFFF) + { + oa->write_character(static_cast<CharType>(0x79)); + write_number(static_cast<uint16_t>(N)); + } + else if (N <= 0xFFFFFFFF) + { + oa->write_character(static_cast<CharType>(0x7A)); + write_number(static_cast<uint32_t>(N)); + } + // LCOV_EXCL_START + else if (N <= 0xFFFFFFFFFFFFFFFF) + { + oa->write_character(static_cast<CharType>(0x7B)); + write_number(static_cast<uint64_t>(N)); + } + // LCOV_EXCL_STOP + + // step 2: write the string + oa->write_characters( + reinterpret_cast<const CharType*>(j.m_value.string->c_str()), + j.m_value.string->size()); + break; + } + + case value_t::array: + { + // step 1: write control byte and the array size + const auto N = j.m_value.array->size(); + if (N <= 0x17) + { + write_number(static_cast<uint8_t>(0x80 + N)); + } + else if (N <= 0xFF) + { + oa->write_character(static_cast<CharType>(0x98)); + write_number(static_cast<uint8_t>(N)); + } + else if (N <= 0xFFFF) + { + oa->write_character(static_cast<CharType>(0x99)); + write_number(static_cast<uint16_t>(N)); + } + else if (N <= 0xFFFFFFFF) + { + oa->write_character(static_cast<CharType>(0x9A)); + write_number(static_cast<uint32_t>(N)); + } + // LCOV_EXCL_START + else if (N <= 0xFFFFFFFFFFFFFFFF) + { + oa->write_character(static_cast<CharType>(0x9B)); + write_number(static_cast<uint64_t>(N)); + } + // LCOV_EXCL_STOP + + // step 2: write each element + for (const auto& el : *j.m_value.array) + { + write_cbor(el); + } + break; + } + + case value_t::object: + { + // step 1: write control byte and the object size + const auto N = j.m_value.object->size(); + if (N <= 0x17) + { + write_number(static_cast<uint8_t>(0xA0 + N)); + } + else if (N <= 0xFF) + { + oa->write_character(static_cast<CharType>(0xB8)); + write_number(static_cast<uint8_t>(N)); + } + else if (N <= 0xFFFF) + { + oa->write_character(static_cast<CharType>(0xB9)); + write_number(static_cast<uint16_t>(N)); + } + else if (N <= 0xFFFFFFFF) + { + oa->write_character(static_cast<CharType>(0xBA)); + write_number(static_cast<uint32_t>(N)); + } + // LCOV_EXCL_START + else if (N <= 0xFFFFFFFFFFFFFFFF) + { + oa->write_character(static_cast<CharType>(0xBB)); + write_number(static_cast<uint64_t>(N)); + } + // LCOV_EXCL_STOP + + // step 2: write each element + for (const auto& el : *j.m_value.object) + { + write_cbor(el.first); + write_cbor(el.second); + } + break; + } + + default: + break; + } + } + + /*! + @brief[in] j JSON value to serialize + */ + void write_msgpack(const BasicJsonType& j) + { + switch (j.type()) + { + case value_t::null: // nil + { + oa->write_character(static_cast<CharType>(0xC0)); + break; + } + + case value_t::boolean: // true and false + { + oa->write_character(j.m_value.boolean + ? static_cast<CharType>(0xC3) + : static_cast<CharType>(0xC2)); + break; + } + + case value_t::number_integer: + { + if (j.m_value.number_integer >= 0) + { + // MessagePack does not differentiate between positive + // signed integers and unsigned integers. Therefore, we used + // the code from the value_t::number_unsigned case here. + if (j.m_value.number_unsigned < 128) + { + // positive fixnum + write_number(static_cast<uint8_t>(j.m_value.number_integer)); + } + else if (j.m_value.number_unsigned <= (std::numeric_limits<uint8_t>::max)()) + { + // uint 8 + oa->write_character(static_cast<CharType>(0xCC)); + write_number(static_cast<uint8_t>(j.m_value.number_integer)); + } + else if (j.m_value.number_unsigned <= (std::numeric_limits<uint16_t>::max)()) + { + // uint 16 + oa->write_character(static_cast<CharType>(0xCD)); + write_number(static_cast<uint16_t>(j.m_value.number_integer)); + } + else if (j.m_value.number_unsigned <= (std::numeric_limits<uint32_t>::max)()) + { + // uint 32 + oa->write_character(static_cast<CharType>(0xCE)); + write_number(static_cast<uint32_t>(j.m_value.number_integer)); + } + else if (j.m_value.number_unsigned <= (std::numeric_limits<uint64_t>::max)()) + { + // uint 64 + oa->write_character(static_cast<CharType>(0xCF)); + write_number(static_cast<uint64_t>(j.m_value.number_integer)); + } + } + else + { + if (j.m_value.number_integer >= -32) + { + // negative fixnum + write_number(static_cast<int8_t>(j.m_value.number_integer)); + } + else if (j.m_value.number_integer >= (std::numeric_limits<int8_t>::min)() and + j.m_value.number_integer <= (std::numeric_limits<int8_t>::max)()) + { + // int 8 + oa->write_character(static_cast<CharType>(0xD0)); + write_number(static_cast<int8_t>(j.m_value.number_integer)); + } + else if (j.m_value.number_integer >= (std::numeric_limits<int16_t>::min)() and + j.m_value.number_integer <= (std::numeric_limits<int16_t>::max)()) + { + // int 16 + oa->write_character(static_cast<CharType>(0xD1)); + write_number(static_cast<int16_t>(j.m_value.number_integer)); + } + else if (j.m_value.number_integer >= (std::numeric_limits<int32_t>::min)() and + j.m_value.number_integer <= (std::numeric_limits<int32_t>::max)()) + { + // int 32 + oa->write_character(static_cast<CharType>(0xD2)); + write_number(static_cast<int32_t>(j.m_value.number_integer)); + } + else if (j.m_value.number_integer >= (std::numeric_limits<int64_t>::min)() and + j.m_value.number_integer <= (std::numeric_limits<int64_t>::max)()) + { + // int 64 + oa->write_character(static_cast<CharType>(0xD3)); + write_number(static_cast<int64_t>(j.m_value.number_integer)); + } + } + break; + } + + case value_t::number_unsigned: + { + if (j.m_value.number_unsigned < 128) + { + // positive fixnum + write_number(static_cast<uint8_t>(j.m_value.number_integer)); + } + else if (j.m_value.number_unsigned <= (std::numeric_limits<uint8_t>::max)()) + { + // uint 8 + oa->write_character(static_cast<CharType>(0xCC)); + write_number(static_cast<uint8_t>(j.m_value.number_integer)); + } + else if (j.m_value.number_unsigned <= (std::numeric_limits<uint16_t>::max)()) + { + // uint 16 + oa->write_character(static_cast<CharType>(0xCD)); + write_number(static_cast<uint16_t>(j.m_value.number_integer)); + } + else if (j.m_value.number_unsigned <= (std::numeric_limits<uint32_t>::max)()) + { + // uint 32 + oa->write_character(static_cast<CharType>(0xCE)); + write_number(static_cast<uint32_t>(j.m_value.number_integer)); + } + else if (j.m_value.number_unsigned <= (std::numeric_limits<uint64_t>::max)()) + { + // uint 64 + oa->write_character(static_cast<CharType>(0xCF)); + write_number(static_cast<uint64_t>(j.m_value.number_integer)); + } + break; + } + + case value_t::number_float: // float 64 + { + oa->write_character(static_cast<CharType>(0xCB)); + write_number(j.m_value.number_float); + break; + } + + case value_t::string: + { + // step 1: write control byte and the string length + const auto N = j.m_value.string->size(); + if (N <= 31) + { + // fixstr + write_number(static_cast<uint8_t>(0xA0 | N)); + } + else if (N <= 255) + { + // str 8 + oa->write_character(static_cast<CharType>(0xD9)); + write_number(static_cast<uint8_t>(N)); + } + else if (N <= 65535) + { + // str 16 + oa->write_character(static_cast<CharType>(0xDA)); + write_number(static_cast<uint16_t>(N)); + } + else if (N <= 4294967295) + { + // str 32 + oa->write_character(static_cast<CharType>(0xDB)); + write_number(static_cast<uint32_t>(N)); + } + + // step 2: write the string + oa->write_characters( + reinterpret_cast<const CharType*>(j.m_value.string->c_str()), + j.m_value.string->size()); + break; + } + + case value_t::array: + { + // step 1: write control byte and the array size + const auto N = j.m_value.array->size(); + if (N <= 15) + { + // fixarray + write_number(static_cast<uint8_t>(0x90 | N)); + } + else if (N <= 0xFFFF) + { + // array 16 + oa->write_character(static_cast<CharType>(0xDC)); + write_number(static_cast<uint16_t>(N)); + } + else if (N <= 0xFFFFFFFF) + { + // array 32 + oa->write_character(static_cast<CharType>(0xDD)); + write_number(static_cast<uint32_t>(N)); + } + + // step 2: write each element + for (const auto& el : *j.m_value.array) + { + write_msgpack(el); + } + break; + } + + case value_t::object: + { + // step 1: write control byte and the object size + const auto N = j.m_value.object->size(); + if (N <= 15) + { + // fixmap + write_number(static_cast<uint8_t>(0x80 | (N & 0xF))); + } + else if (N <= 65535) + { + // map 16 + oa->write_character(static_cast<CharType>(0xDE)); + write_number(static_cast<uint16_t>(N)); + } + else if (N <= 4294967295) + { + // map 32 + oa->write_character(static_cast<CharType>(0xDF)); + write_number(static_cast<uint32_t>(N)); + } + + // step 2: write each element + for (const auto& el : *j.m_value.object) + { + write_msgpack(el.first); + write_msgpack(el.second); + } + break; + } + + default: + break; + } + } + + private: + /* + @brief write a number to output input + + @param[in] n number of type @a NumberType + @tparam NumberType the type of the number + + @note This function needs to respect the system's endianess, because bytes + in CBOR and MessagePack are stored in network order (big endian) and + therefore need reordering on little endian systems. + */ + template<typename NumberType> void write_number(NumberType n) { - return '.'; + // step 1: write number to array of length NumberType + std::array<CharType, sizeof(NumberType)> vec; + std::memcpy(vec.data(), &n, sizeof(NumberType)); + + // step 2: write array to output (with possible reordering) + if (is_little_endian) + { + // reverse byte order prior to conversion if necessary + std::reverse(vec.begin(), vec.end()); + } + + oa->write_characters(vec.data(), sizeof(NumberType)); } + + private: + /// whether we can assume little endianess + const bool is_little_endian = binary_reader<BasicJsonType>::little_endianess(); + + /// the output + output_adapter_t<CharType> oa = nullptr; }; +/////////////////// +// serialization // +/////////////////// + +template<typename BasicJsonType> +class serializer +{ + using string_t = typename BasicJsonType::string_t; + using number_float_t = typename BasicJsonType::number_float_t; + using number_integer_t = typename BasicJsonType::number_integer_t; + using number_unsigned_t = typename BasicJsonType::number_unsigned_t; + public: + /*! + @param[in] s output stream to serialize to + @param[in] ichar indentation character to use + */ + serializer(output_adapter_t<char> s, const char ichar) + : o(std::move(s)), loc(std::localeconv()), + thousands_sep(loc->thousands_sep == nullptr ? '\0' : * (loc->thousands_sep)), + decimal_point(loc->decimal_point == nullptr ? '\0' : * (loc->decimal_point)), + indent_char(ichar), indent_string(512, indent_char) {} + + // delete because of pointer members + serializer(const serializer&) = delete; + serializer& operator=(const serializer&) = delete; + + /*! + @brief internal implementation of the serialization function + + This function is called by the public member function dump and organizes + the serialization internally. The indentation level is propagated as + additional parameter. In case of arrays and objects, the function is + called recursively. + + - strings and object keys are escaped using `escape_string()` + - integer numbers are converted implicitly via `operator<<` + - floating-point numbers are converted to a string using `"%g"` format + + @param[in] val value to serialize + @param[in] pretty_print whether the output shall be pretty-printed + @param[in] indent_step the indent level + @param[in] current_indent the current indent level (only used internally) + */ + void dump(const BasicJsonType& val, const bool pretty_print, + const bool ensure_ascii, + const unsigned int indent_step, + const unsigned int current_indent = 0) + { + switch (val.m_type) + { + case value_t::object: + { + if (val.m_value.object->empty()) + { + o->write_characters("{}", 2); + return; + } + + if (pretty_print) + { + o->write_characters("{\n", 2); + + // variable to hold indentation for recursive calls + const auto new_indent = current_indent + indent_step; + if (JSON_UNLIKELY(indent_string.size() < new_indent)) + { + indent_string.resize(indent_string.size() * 2, ' '); + } + + // first n-1 elements + auto i = val.m_value.object->cbegin(); + for (std::size_t cnt = 0; cnt < val.m_value.object->size() - 1; ++cnt, ++i) + { + o->write_characters(indent_string.c_str(), new_indent); + o->write_character('\"'); + dump_escaped(i->first, ensure_ascii); + o->write_characters("\": ", 3); + dump(i->second, true, ensure_ascii, indent_step, new_indent); + o->write_characters(",\n", 2); + } + + // last element + assert(i != val.m_value.object->cend()); + assert(std::next(i) == val.m_value.object->cend()); + o->write_characters(indent_string.c_str(), new_indent); + o->write_character('\"'); + dump_escaped(i->first, ensure_ascii); + o->write_characters("\": ", 3); + dump(i->second, true, ensure_ascii, indent_step, new_indent); + + o->write_character('\n'); + o->write_characters(indent_string.c_str(), current_indent); + o->write_character('}'); + } + else + { + o->write_character('{'); + + // first n-1 elements + auto i = val.m_value.object->cbegin(); + for (std::size_t cnt = 0; cnt < val.m_value.object->size() - 1; ++cnt, ++i) + { + o->write_character('\"'); + dump_escaped(i->first, ensure_ascii); + o->write_characters("\":", 2); + dump(i->second, false, ensure_ascii, indent_step, current_indent); + o->write_character(','); + } + + // last element + assert(i != val.m_value.object->cend()); + assert(std::next(i) == val.m_value.object->cend()); + o->write_character('\"'); + dump_escaped(i->first, ensure_ascii); + o->write_characters("\":", 2); + dump(i->second, false, ensure_ascii, indent_step, current_indent); + + o->write_character('}'); + } + + return; + } + + case value_t::array: + { + if (val.m_value.array->empty()) + { + o->write_characters("[]", 2); + return; + } + + if (pretty_print) + { + o->write_characters("[\n", 2); + + // variable to hold indentation for recursive calls + const auto new_indent = current_indent + indent_step; + if (JSON_UNLIKELY(indent_string.size() < new_indent)) + { + indent_string.resize(indent_string.size() * 2, ' '); + } + + // first n-1 elements + for (auto i = val.m_value.array->cbegin(); + i != val.m_value.array->cend() - 1; ++i) + { + o->write_characters(indent_string.c_str(), new_indent); + dump(*i, true, ensure_ascii, indent_step, new_indent); + o->write_characters(",\n", 2); + } + + // last element + assert(not val.m_value.array->empty()); + o->write_characters(indent_string.c_str(), new_indent); + dump(val.m_value.array->back(), true, ensure_ascii, indent_step, new_indent); + + o->write_character('\n'); + o->write_characters(indent_string.c_str(), current_indent); + o->write_character(']'); + } + else + { + o->write_character('['); + + // first n-1 elements + for (auto i = val.m_value.array->cbegin(); + i != val.m_value.array->cend() - 1; ++i) + { + dump(*i, false, ensure_ascii, indent_step, current_indent); + o->write_character(','); + } + + // last element + assert(not val.m_value.array->empty()); + dump(val.m_value.array->back(), false, ensure_ascii, indent_step, current_indent); + + o->write_character(']'); + } + + return; + } + + case value_t::string: + { + o->write_character('\"'); + dump_escaped(*val.m_value.string, ensure_ascii); + o->write_character('\"'); + return; + } + + case value_t::boolean: + { + if (val.m_value.boolean) + { + o->write_characters("true", 4); + } + else + { + o->write_characters("false", 5); + } + return; + } + + case value_t::number_integer: + { + dump_integer(val.m_value.number_integer); + return; + } + + case value_t::number_unsigned: + { + dump_integer(val.m_value.number_unsigned); + return; + } + + case value_t::number_float: + { + dump_float(val.m_value.number_float); + return; + } + + case value_t::discarded: + { + o->write_characters("<discarded>", 11); + return; + } + + case value_t::null: + { + o->write_characters("null", 4); + return; + } + } + } + + private: + /*! + @brief returns the number of expected bytes following in UTF-8 string + + @param[in] u the first byte of a UTF-8 string + @return the number of expected bytes following + */ + static constexpr std::size_t bytes_following(const uint8_t u) + { + return ((u <= 127) ? 0 + : ((192 <= u and u <= 223) ? 1 + : ((224 <= u and u <= 239) ? 2 + : ((240 <= u and u <= 247) ? 3 : std::string::npos)))); + } + + /*! + @brief calculates the extra space to escape a JSON string + + @param[in] s the string to escape + @param[in] ensure_ascii whether to escape non-ASCII characters with + \uXXXX sequences + @return the number of characters required to escape string @a s + + @complexity Linear in the length of string @a s. + */ + static std::size_t extra_space(const string_t& s, + const bool ensure_ascii) noexcept + { + std::size_t res = 0; + + for (std::size_t i = 0; i < s.size(); ++i) + { + switch (s[i]) + { + // control characters that can be escaped with a backslash + case '"': + case '\\': + case '\b': + case '\f': + case '\n': + case '\r': + case '\t': + { + // from c (1 byte) to \x (2 bytes) + res += 1; + break; + } + + // control characters that need \uxxxx escaping + case 0x00: + case 0x01: + case 0x02: + case 0x03: + case 0x04: + case 0x05: + case 0x06: + case 0x07: + case 0x0B: + case 0x0E: + case 0x0F: + case 0x10: + case 0x11: + case 0x12: + case 0x13: + case 0x14: + case 0x15: + case 0x16: + case 0x17: + case 0x18: + case 0x19: + case 0x1A: + case 0x1B: + case 0x1C: + case 0x1D: + case 0x1E: + case 0x1F: + { + // from c (1 byte) to \uxxxx (6 bytes) + res += 5; + break; + } + + default: + { + if (ensure_ascii and (s[i] & 0x80 or s[i] == 0x7F)) + { + const auto bytes = bytes_following(static_cast<uint8_t>(s[i])); + // invalid characters will be detected by throw_if_invalid_utf8 + assert (bytes != std::string::npos); + + if (bytes == 3) + { + // codepoints that need 4 bytes (i.e., 3 additional + // bytes) in UTF-8 need a surrogate pair when \u + // escaping is used: from 4 bytes to \uxxxx\uxxxx + // (12 bytes) + res += (12 - bytes - 1); + } + else + { + // from x bytes to \uxxxx (6 bytes) + res += (6 - bytes - 1); + } + + // skip the additional bytes + i += bytes; + } + break; + } + } + } + + return res; + } + + static void escape_codepoint(int codepoint, string_t& result, std::size_t& pos) + { + // expecting a proper codepoint + assert(0x00 <= codepoint and codepoint <= 0x10FFFF); + + // the last written character was the backslash before the 'u' + assert(result[pos] == '\\'); + + // write the 'u' + result[++pos] = 'u'; + + // convert a number 0..15 to its hex representation (0..f) + static const std::array<char, 16> hexify = + { + { + '0', '1', '2', '3', '4', '5', '6', '7', + '8', '9', 'a', 'b', 'c', 'd', 'e', 'f' + } + }; + + if (codepoint < 0x10000) + { + // codepoints U+0000..U+FFFF can be represented as \uxxxx. + result[++pos] = hexify[(codepoint >> 12) & 0x0F]; + result[++pos] = hexify[(codepoint >> 8) & 0x0F]; + result[++pos] = hexify[(codepoint >> 4) & 0x0F]; + result[++pos] = hexify[codepoint & 0x0F]; + } + else + { + // codepoints U+10000..U+10FFFF need a surrogate pair to be + // represented as \uxxxx\uxxxx. + // http://www.unicode.org/faq/utf_bom.html#utf16-4 + codepoint -= 0x10000; + const int high_surrogate = 0xD800 | ((codepoint >> 10) & 0x3FF); + const int low_surrogate = 0xDC00 | (codepoint & 0x3FF); + result[++pos] = hexify[(high_surrogate >> 12) & 0x0F]; + result[++pos] = hexify[(high_surrogate >> 8) & 0x0F]; + result[++pos] = hexify[(high_surrogate >> 4) & 0x0F]; + result[++pos] = hexify[high_surrogate & 0x0F]; + ++pos; // backslash is already in output + result[++pos] = 'u'; + result[++pos] = hexify[(low_surrogate >> 12) & 0x0F]; + result[++pos] = hexify[(low_surrogate >> 8) & 0x0F]; + result[++pos] = hexify[(low_surrogate >> 4) & 0x0F]; + result[++pos] = hexify[low_surrogate & 0x0F]; + } + + ++pos; + } + + /*! + @brief dump escaped string + + Escape a string by replacing certain special characters by a sequence of an + escape character (backslash) and another character and other control + characters by a sequence of "\u" followed by a four-digit hex + representation. The escaped string is written to output stream @a o. + + @param[in] s the string to escape + @param[in] ensure_ascii whether to escape non-ASCII characters with + \uXXXX sequences + + @complexity Linear in the length of string @a s. + */ + void dump_escaped(const string_t& s, const bool ensure_ascii) const + { + throw_if_invalid_utf8(s); + + const auto space = extra_space(s, ensure_ascii); + if (space == 0) + { + o->write_characters(s.c_str(), s.size()); + return; + } + + // create a result string of necessary size + string_t result(s.size() + space, '\\'); + std::size_t pos = 0; + + for (std::size_t i = 0; i < s.size(); ++i) + { + switch (s[i]) + { + case '"': // quotation mark (0x22) + { + result[pos + 1] = '"'; + pos += 2; + break; + } + + case '\\': // reverse solidus (0x5C) + { + // nothing to change + pos += 2; + break; + } + + case '\b': // backspace (0x08) + { + result[pos + 1] = 'b'; + pos += 2; + break; + } + + case '\f': // formfeed (0x0C) + { + result[pos + 1] = 'f'; + pos += 2; + break; + } + + case '\n': // newline (0x0A) + { + result[pos + 1] = 'n'; + pos += 2; + break; + } + + case '\r': // carriage return (0x0D) + { + result[pos + 1] = 'r'; + pos += 2; + break; + } + + case '\t': // horizontal tab (0x09) + { + result[pos + 1] = 't'; + pos += 2; + break; + } + + default: + { + // escape control characters (0x00..0x1F) or, if + // ensure_ascii parameter is used, non-ASCII characters + if ((0x00 <= s[i] and s[i] <= 0x1F) or + (ensure_ascii and (s[i] & 0x80 or s[i] == 0x7F))) + { + const auto bytes = bytes_following(static_cast<uint8_t>(s[i])); + // invalid characters will be detected by throw_if_invalid_utf8 + assert (bytes != std::string::npos); + + // check that the additional bytes are present + assert(i + bytes < s.size()); + + // to use \uxxxx escaping, we first need to calculate + // the codepoint from the UTF-8 bytes + int codepoint = 0; + + // bytes is unsigned type: + assert(bytes <= 3); + switch (bytes) + { + case 0: + { + codepoint = s[i] & 0xFF; + break; + } + + case 1: + { + codepoint = ((s[i] & 0x3F) << 6) + + (s[i + 1] & 0x7F); + break; + } + + case 2: + { + codepoint = ((s[i] & 0x1F) << 12) + + ((s[i + 1] & 0x7F) << 6) + + (s[i + 2] & 0x7F); + break; + } + + case 3: + { + codepoint = ((s[i] & 0xF) << 18) + + ((s[i + 1] & 0x7F) << 12) + + ((s[i + 2] & 0x7F) << 6) + + (s[i + 3] & 0x7F); + break; + } + + default: + break; // LCOV_EXCL_LINE + } + + escape_codepoint(codepoint, result, pos); + i += bytes; + } + else + { + // all other characters are added as-is + result[pos++] = s[i]; + } + break; + } + } + } + + assert(pos == result.size()); + o->write_characters(result.c_str(), result.size()); + } + + /*! + @brief dump an integer + + Dump a given integer to output stream @a o. Works internally with + @a number_buffer. + + @param[in] x integer number (signed or unsigned) to dump + @tparam NumberType either @a number_integer_t or @a number_unsigned_t + */ + template<typename NumberType, detail::enable_if_t< + std::is_same<NumberType, number_unsigned_t>::value or + std::is_same<NumberType, number_integer_t>::value, + int> = 0> + void dump_integer(NumberType x) + { + // special case for "0" + if (x == 0) + { + o->write_character('0'); + return; + } + + const bool is_negative = (x <= 0) and (x != 0); // see issue #755 + std::size_t i = 0; + + while (x != 0) + { + // spare 1 byte for '\0' + assert(i < number_buffer.size() - 1); + + const auto digit = std::labs(static_cast<long>(x % 10)); + number_buffer[i++] = static_cast<char>('0' + digit); + x /= 10; + } + + if (is_negative) + { + // make sure there is capacity for the '-' + assert(i < number_buffer.size() - 2); + number_buffer[i++] = '-'; + } + + std::reverse(number_buffer.begin(), number_buffer.begin() + i); + o->write_characters(number_buffer.data(), i); + } + + /*! + @brief dump a floating-point number + + Dump a given floating-point number to output stream @a o. Works internally + with @a number_buffer. + + @param[in] x floating-point number to dump + */ + void dump_float(number_float_t x) + { + // NaN / inf + if (not std::isfinite(x) or std::isnan(x)) + { + o->write_characters("null", 4); + return; + } + + // get number of digits for a text -> float -> text round-trip + static constexpr auto d = std::numeric_limits<number_float_t>::digits10; + + // the actual conversion + std::ptrdiff_t len = snprintf(number_buffer.data(), number_buffer.size(), "%.*g", d, x); + + // negative value indicates an error + assert(len > 0); + // check if buffer was large enough + assert(static_cast<std::size_t>(len) < number_buffer.size()); + + // erase thousands separator + if (thousands_sep != '\0') + { + const auto end = std::remove(number_buffer.begin(), + number_buffer.begin() + len, thousands_sep); + std::fill(end, number_buffer.end(), '\0'); + assert((end - number_buffer.begin()) <= len); + len = (end - number_buffer.begin()); + } + + // convert decimal point to '.' + if (decimal_point != '\0' and decimal_point != '.') + { + const auto dec_pos = std::find(number_buffer.begin(), number_buffer.end(), decimal_point); + if (dec_pos != number_buffer.end()) + { + *dec_pos = '.'; + } + } + + o->write_characters(number_buffer.data(), static_cast<std::size_t>(len)); + + // determine if need to append ".0" + const bool value_is_int_like = + std::none_of(number_buffer.begin(), number_buffer.begin() + len + 1, + [](char c) + { + return (c == '.' or c == 'e'); + }); + + if (value_is_int_like) + { + o->write_characters(".0", 2); + } + } + + /*! + @brief check whether a string is UTF-8 encoded + + The function checks each byte of a string whether it is UTF-8 encoded. The + result of the check is stored in the @a state parameter. The function must + be called initially with state 0 (accept). State 1 means the string must + be rejected, because the current byte is not allowed. If the string is + completely processed, but the state is non-zero, the string ended + prematurely; that is, the last byte indicated more bytes should have + followed. + + @param[in,out] state the state of the decoding + @param[in] byte next byte to decode + + @note The function has been edited: a std::array is used and the code + point is not calculated. + + @copyright Copyright (c) 2008-2009 Bjoern Hoehrmann <bjoern@hoehrmann.de> + @sa http://bjoern.hoehrmann.de/utf-8/decoder/dfa/ + */ + static void decode(uint8_t& state, const uint8_t byte) + { + static const std::array<uint8_t, 400> utf8d = + { + { + 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, // 00..1F + 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, // 20..3F + 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, // 40..5F + 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, // 60..7F + 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, // 80..9F + 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, // A0..BF + 8, 8, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, // C0..DF + 0xA, 0x3, 0x3, 0x3, 0x3, 0x3, 0x3, 0x3, 0x3, 0x3, 0x3, 0x3, 0x3, 0x4, 0x3, 0x3, // E0..EF + 0xB, 0x6, 0x6, 0x6, 0x5, 0x8, 0x8, 0x8, 0x8, 0x8, 0x8, 0x8, 0x8, 0x8, 0x8, 0x8, // F0..FF + 0x0, 0x1, 0x2, 0x3, 0x5, 0x8, 0x7, 0x1, 0x1, 0x1, 0x4, 0x6, 0x1, 0x1, 0x1, 0x1, // s0..s0 + 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 1, 1, 1, 1, 1, 0, 1, 0, 1, 1, 1, 1, 1, 1, // s1..s2 + 1, 2, 1, 1, 1, 1, 1, 2, 1, 2, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 2, 1, 1, 1, 1, 1, 1, 1, 1, // s3..s4 + 1, 2, 1, 1, 1, 1, 1, 1, 1, 2, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 3, 1, 3, 1, 1, 1, 1, 1, 1, // s5..s6 + 1, 3, 1, 1, 1, 1, 1, 3, 1, 3, 1, 1, 1, 1, 1, 1, 1, 3, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1 // s7..s8 + } + }; + + const uint8_t type = utf8d[byte]; + state = utf8d[256u + state * 16u + type]; + } + + /*! + @brief throw an exception if a string is not UTF-8 encoded + + @param[in] str UTF-8 string to check + @throw type_error.316 if passed string is not UTF-8 encoded + + @since version 3.0.0 + */ + static void throw_if_invalid_utf8(const std::string& str) + { + // start with state 0 (= accept) + uint8_t state = 0; + + for (size_t i = 0; i < str.size(); ++i) + { + const auto byte = static_cast<uint8_t>(str[i]); + decode(state, byte); + if (state == 1) + { + // state 1 means reject + std::stringstream ss; + ss << std::setw(2) << std::uppercase << std::setfill('0') << std::hex << static_cast<int>(byte); + JSON_THROW(type_error::create(316, "invalid UTF-8 byte at index " + std::to_string(i) + ": 0x" + ss.str())); + } + } + + if (state != 0) + { + // we finish reading, but do not accept: string was incomplete + std::stringstream ss; + ss << std::setw(2) << std::uppercase << std::setfill('0') << std::hex << static_cast<int>(static_cast<uint8_t>(str.back())); + JSON_THROW(type_error::create(316, "incomplete UTF-8 string; last byte: 0x" + ss.str())); + } + } + + private: + /// the output of the serializer + output_adapter_t<char> o = nullptr; + + /// a (hopefully) large enough character buffer + std::array<char, 64> number_buffer{{}}; + + /// the locale + const std::lconv* loc = nullptr; + /// the locale's thousand separator character + const char thousands_sep = '\0'; + /// the locale's decimal point character + const char decimal_point = '\0'; + + /// the indentation character + const char indent_char; + + /// the indentation string + string_t indent_string; +}; + +template<typename BasicJsonType> +class json_ref +{ + public: + using value_type = BasicJsonType; + + json_ref(value_type&& value) + : owned_value(std::move(value)), value_ref(&owned_value), is_rvalue(true) + {} + + json_ref(const value_type& value) + : value_ref(const_cast<value_type*>(&value)), is_rvalue(false) + {} + + json_ref(std::initializer_list<json_ref> init) + : owned_value(init), value_ref(&owned_value), is_rvalue(true) + {} + + template<class... Args> + json_ref(Args&& ... args) + : owned_value(std::forward<Args>(args)...), value_ref(&owned_value), is_rvalue(true) + {} + + // class should be movable only + json_ref(json_ref&&) = default; + json_ref(const json_ref&) = delete; + json_ref& operator=(const json_ref&) = delete; + + value_type moved_or_copied() const + { + if (is_rvalue) + { + return std::move(*value_ref); + } + return *value_ref; + } + + value_type const& operator*() const + { + return *static_cast<value_type const*>(value_ref); + } + + value_type const* operator->() const + { + return static_cast<value_type const*>(value_ref); + } + + private: + mutable value_type owned_value = nullptr; + value_type* value_ref = nullptr; + const bool is_rvalue; +}; + +} // namespace detail + +/// namespace to hold default `to_json` / `from_json` functions +namespace +{ +constexpr const auto& to_json = detail::static_const<detail::to_json_fn>::value; +constexpr const auto& from_json = detail::static_const<detail::from_json_fn>::value; } + +/*! +@brief default JSONSerializer template argument + +This serializer ignores the template arguments and uses ADL +([argument-dependent lookup](http://en.cppreference.com/w/cpp/language/adl)) +for serialization. +*/ +template<typename, typename> +struct adl_serializer +{ + /*! + @brief convert a JSON value to any value type + + This function is usually called by the `get()` function of the + @ref basic_json class (either explicit or via conversion operators). + + @param[in] j JSON value to read from + @param[in,out] val value to write to + */ + template<typename BasicJsonType, typename ValueType> + static void from_json(BasicJsonType&& j, ValueType& val) noexcept( + noexcept(::nlohmann::from_json(std::forward<BasicJsonType>(j), val))) + { + ::nlohmann::from_json(std::forward<BasicJsonType>(j), val); + } + + /*! + @brief convert any value type to a JSON value + + This function is usually called by the constructors of the @ref basic_json + class. + + @param[in,out] j JSON value to write to + @param[in] val value to read from + */ + template<typename BasicJsonType, typename ValueType> + static void to_json(BasicJsonType& j, ValueType&& val) noexcept( + noexcept(::nlohmann::to_json(j, std::forward<ValueType>(val)))) + { + ::nlohmann::to_json(j, std::forward<ValueType>(val)); + } +}; + +/*! +@brief JSON Pointer + +A JSON pointer defines a string syntax for identifying a specific value +within a JSON document. It can be used with functions `at` and +`operator[]`. Furthermore, JSON pointers are the base for JSON patches. + +@sa [RFC 6901](https://tools.ietf.org/html/rfc6901) + +@since version 2.0.0 +*/ +class json_pointer +{ + /// allow basic_json to access private members + NLOHMANN_BASIC_JSON_TPL_DECLARATION + friend class basic_json; + + public: + /*! + @brief create JSON pointer + + Create a JSON pointer according to the syntax described in + [Section 3 of RFC6901](https://tools.ietf.org/html/rfc6901#section-3). + + @param[in] s string representing the JSON pointer; if omitted, the empty + string is assumed which references the whole JSON value + + @throw parse_error.107 if the given JSON pointer @a s is nonempty and + does not begin with a slash (`/`); see example below + + @throw parse_error.108 if a tilde (`~`) in the given JSON pointer @a s + is not followed by `0` (representing `~`) or `1` (representing `/`); + see example below + + @liveexample{The example shows the construction several valid JSON + pointers as well as the exceptional behavior.,json_pointer} + + @since version 2.0.0 + */ + explicit json_pointer(const std::string& s = "") : reference_tokens(split(s)) {} + + /*! + @brief return a string representation of the JSON pointer + + @invariant For each JSON pointer `ptr`, it holds: + @code {.cpp} + ptr == json_pointer(ptr.to_string()); + @endcode + + @return a string representation of the JSON pointer + + @liveexample{The example shows the result of `to_string`., + json_pointer__to_string} + + @since version 2.0.0 + */ + std::string to_string() const noexcept + { + return std::accumulate(reference_tokens.begin(), reference_tokens.end(), + std::string{}, + [](const std::string & a, const std::string & b) + { + return a + "/" + escape(b); + }); + } + + /// @copydoc to_string() + operator std::string() const + { + return to_string(); + } + + /*! + @param[in] s reference token to be converted into an array index + + @return integer representation of @a s + + @throw out_of_range.404 if string @a s could not be converted to an integer + */ + static int array_index(const std::string& s) + { + size_t processed_chars = 0; + const int res = std::stoi(s, &processed_chars); + + // check if the string was completely read + if (JSON_UNLIKELY(processed_chars != s.size())) + { + JSON_THROW(detail::out_of_range::create(404, "unresolved reference token '" + s + "'")); + } + + return res; + } + + private: + /*! + @brief remove and return last reference pointer + @throw out_of_range.405 if JSON pointer has no parent + */ + std::string pop_back() + { + if (JSON_UNLIKELY(is_root())) + { + JSON_THROW(detail::out_of_range::create(405, "JSON pointer has no parent")); + } + + auto last = reference_tokens.back(); + reference_tokens.pop_back(); + return last; + } + + /// return whether pointer points to the root document + bool is_root() const + { + return reference_tokens.empty(); + } + + json_pointer top() const + { + if (JSON_UNLIKELY(is_root())) + { + JSON_THROW(detail::out_of_range::create(405, "JSON pointer has no parent")); + } + + json_pointer result = *this; + result.reference_tokens = {reference_tokens[0]}; + return result; + } + + /*! + @brief create and return a reference to the pointed to value + + @complexity Linear in the number of reference tokens. + + @throw parse_error.109 if array index is not a number + @throw type_error.313 if value cannot be unflattened + */ + NLOHMANN_BASIC_JSON_TPL_DECLARATION + NLOHMANN_BASIC_JSON_TPL& get_and_create(NLOHMANN_BASIC_JSON_TPL& j) const; + + /*! + @brief return a reference to the pointed to value + + @note This version does not throw if a value is not present, but tries to + create nested values instead. For instance, calling this function + with pointer `"/this/that"` on a null value is equivalent to calling + `operator[]("this").operator[]("that")` on that value, effectively + changing the null value to an object. + + @param[in] ptr a JSON value + + @return reference to the JSON value pointed to by the JSON pointer + + @complexity Linear in the length of the JSON pointer. + + @throw parse_error.106 if an array index begins with '0' + @throw parse_error.109 if an array index was not a number + @throw out_of_range.404 if the JSON pointer can not be resolved + */ + NLOHMANN_BASIC_JSON_TPL_DECLARATION + NLOHMANN_BASIC_JSON_TPL& get_unchecked(NLOHMANN_BASIC_JSON_TPL* ptr) const; + + /*! + @throw parse_error.106 if an array index begins with '0' + @throw parse_error.109 if an array index was not a number + @throw out_of_range.402 if the array index '-' is used + @throw out_of_range.404 if the JSON pointer can not be resolved + */ + NLOHMANN_BASIC_JSON_TPL_DECLARATION + NLOHMANN_BASIC_JSON_TPL& get_checked(NLOHMANN_BASIC_JSON_TPL* ptr) const; + + /*! + @brief return a const reference to the pointed to value + + @param[in] ptr a JSON value + + @return const reference to the JSON value pointed to by the JSON + pointer + + @throw parse_error.106 if an array index begins with '0' + @throw parse_error.109 if an array index was not a number + @throw out_of_range.402 if the array index '-' is used + @throw out_of_range.404 if the JSON pointer can not be resolved + */ + NLOHMANN_BASIC_JSON_TPL_DECLARATION + const NLOHMANN_BASIC_JSON_TPL& get_unchecked(const NLOHMANN_BASIC_JSON_TPL* ptr) const; + + /*! + @throw parse_error.106 if an array index begins with '0' + @throw parse_error.109 if an array index was not a number + @throw out_of_range.402 if the array index '-' is used + @throw out_of_range.404 if the JSON pointer can not be resolved + */ + NLOHMANN_BASIC_JSON_TPL_DECLARATION + const NLOHMANN_BASIC_JSON_TPL& get_checked(const NLOHMANN_BASIC_JSON_TPL* ptr) const; + + /*! + @brief split the string input to reference tokens + + @note This function is only called by the json_pointer constructor. + All exceptions below are documented there. + + @throw parse_error.107 if the pointer is not empty or begins with '/' + @throw parse_error.108 if character '~' is not followed by '0' or '1' + */ + static std::vector<std::string> split(const std::string& reference_string) + { + std::vector<std::string> result; + + // special case: empty reference string -> no reference tokens + if (reference_string.empty()) + { + return result; + } + + // check if nonempty reference string begins with slash + if (JSON_UNLIKELY(reference_string[0] != '/')) + { + JSON_THROW(detail::parse_error::create(107, 1, + "JSON pointer must be empty or begin with '/' - was: '" + + reference_string + "'")); + } + + // extract the reference tokens: + // - slash: position of the last read slash (or end of string) + // - start: position after the previous slash + for ( + // search for the first slash after the first character + std::size_t slash = reference_string.find_first_of('/', 1), + // set the beginning of the first reference token + start = 1; + // we can stop if start == string::npos+1 = 0 + start != 0; + // set the beginning of the next reference token + // (will eventually be 0 if slash == std::string::npos) + start = slash + 1, + // find next slash + slash = reference_string.find_first_of('/', start)) + { + // use the text between the beginning of the reference token + // (start) and the last slash (slash). + auto reference_token = reference_string.substr(start, slash - start); + + // check reference tokens are properly escaped + for (std::size_t pos = reference_token.find_first_of('~'); + pos != std::string::npos; + pos = reference_token.find_first_of('~', pos + 1)) + { + assert(reference_token[pos] == '~'); + + // ~ must be followed by 0 or 1 + if (JSON_UNLIKELY(pos == reference_token.size() - 1 or + (reference_token[pos + 1] != '0' and + reference_token[pos + 1] != '1'))) + { + JSON_THROW(detail::parse_error::create(108, 0, "escape character '~' must be followed with '0' or '1'")); + } + } + + // finally, store the reference token + unescape(reference_token); + result.push_back(reference_token); + } + + return result; + } + + /*! + @brief replace all occurrences of a substring by another string + + @param[in,out] s the string to manipulate; changed so that all + occurrences of @a f are replaced with @a t + @param[in] f the substring to replace with @a t + @param[in] t the string to replace @a f + + @pre The search string @a f must not be empty. **This precondition is + enforced with an assertion.** + + @since version 2.0.0 + */ + static void replace_substring(std::string& s, const std::string& f, + const std::string& t) + { + assert(not f.empty()); + for (auto pos = s.find(f); // find first occurrence of f + pos != std::string::npos; // make sure f was found + s.replace(pos, f.size(), t), // replace with t, and + pos = s.find(f, pos + t.size())) // find next occurrence of f + {} + } + + /// escape "~"" to "~0" and "/" to "~1" + static std::string escape(std::string s) + { + replace_substring(s, "~", "~0"); + replace_substring(s, "/", "~1"); + return s; + } + + /// unescape "~1" to tilde and "~0" to slash (order is important!) + static void unescape(std::string& s) + { + replace_substring(s, "~1", "/"); + replace_substring(s, "~0", "~"); + } + + /*! + @param[in] reference_string the reference string to the current value + @param[in] value the value to consider + @param[in,out] result the result object to insert values to + + @note Empty objects or arrays are flattened to `null`. + */ + NLOHMANN_BASIC_JSON_TPL_DECLARATION + static void flatten(const std::string& reference_string, + const NLOHMANN_BASIC_JSON_TPL& value, + NLOHMANN_BASIC_JSON_TPL& result); + + /*! + @param[in] value flattened JSON + + @return unflattened JSON + + @throw parse_error.109 if array index is not a number + @throw type_error.314 if value is not an object + @throw type_error.315 if object values are not primitive + @throw type_error.313 if value cannot be unflattened + */ + NLOHMANN_BASIC_JSON_TPL_DECLARATION + static NLOHMANN_BASIC_JSON_TPL + unflatten(const NLOHMANN_BASIC_JSON_TPL& value); + + friend bool operator==(json_pointer const& lhs, + json_pointer const& rhs) noexcept; + + friend bool operator!=(json_pointer const& lhs, + json_pointer const& rhs) noexcept; + + /// the reference tokens + std::vector<std::string> reference_tokens; +}; + /*! @brief a class to store JSON values @@ -122,11 +7300,14 @@ default; will be used in @ref number_integer_t) default; will be used in @ref number_float_t) @tparam AllocatorType type of the allocator to use (`std::allocator` by default) +@tparam JSONSerializer the serializer to resolve internal calls to `to_json()` +and `from_json()` (@ref adl_serializer by default) @requirement The class satisfies the following concept requirements: - Basic - [DefaultConstructible](http://en.cppreference.com/w/cpp/concept/DefaultConstructible): - JSON values can be default constructed. The result will be a JSON null value. + JSON values can be default constructed. The result will be a JSON null + value. - [MoveConstructible](http://en.cppreference.com/w/cpp/concept/MoveConstructible): A JSON value can be constructed from an rvalue argument. - [CopyConstructible](http://en.cppreference.com/w/cpp/concept/CopyConstructible): @@ -141,8 +7322,8 @@ default) - [StandardLayoutType](http://en.cppreference.com/w/cpp/concept/StandardLayoutType): JSON values have [standard layout](http://en.cppreference.com/w/cpp/language/data_members#Standard_layout): - All non-static data members are private and standard layout types, the class - has no virtual functions or (virtual) base classes. + All non-static data members are private and standard layout types, the + class has no virtual functions or (virtual) base classes. - Library-wide - [EqualityComparable](http://en.cppreference.com/w/cpp/concept/EqualityComparable): JSON values can be compared with `==`, see @ref @@ -163,6 +7344,13 @@ default) JSON values can be used like STL containers and provide reverse iterator access. +@invariant The member variables @a m_value and @a m_type have the following +relationship: +- If `m_type == value_t::object`, then `m_value.object != nullptr`. +- If `m_type == value_t::array`, then `m_value.array != nullptr`. +- If `m_type == value_t::string`, then `m_value.string != nullptr`. +The invariants are checked by member function assert_invariant(). + @internal @note ObjectType trick from http://stackoverflow.com/a/9860911 @endinternal @@ -174,39 +7362,85 @@ Format](http://rfc7159.net/rfc7159) @nosubgrouping */ -template < - template<typename U, typename V, typename... Args> class ObjectType = std::map, - template<typename U, typename... Args> class ArrayType = std::vector, - class StringType = std::string, - class BooleanType = bool, - class NumberIntegerType = std::int64_t, - class NumberUnsignedType = std::uint64_t, - class NumberFloatType = double, - template<typename U> class AllocatorType = std::allocator - > +NLOHMANN_BASIC_JSON_TPL_DECLARATION class basic_json { private: + template<detail::value_t> friend struct detail::external_constructor; + friend ::nlohmann::json_pointer; + friend ::nlohmann::detail::parser<basic_json>; + friend ::nlohmann::detail::serializer<basic_json>; + template<typename BasicJsonType> + friend class ::nlohmann::detail::iter_impl; + template<typename BasicJsonType, typename CharType> + friend class ::nlohmann::detail::binary_writer; + template<typename BasicJsonType> + friend class ::nlohmann::detail::binary_reader; + /// workaround type for MSVC - using basic_json_t = basic_json<ObjectType, - ArrayType, - StringType, - BooleanType, - NumberIntegerType, - NumberUnsignedType, - NumberFloatType, - AllocatorType>; + using basic_json_t = NLOHMANN_BASIC_JSON_TPL; + + // convenience aliases for types residing in namespace detail; + using lexer = ::nlohmann::detail::lexer<basic_json>; + using parser = ::nlohmann::detail::parser<basic_json>; + + using primitive_iterator_t = ::nlohmann::detail::primitive_iterator_t; + template<typename BasicJsonType> + using internal_iterator = ::nlohmann::detail::internal_iterator<BasicJsonType>; + template<typename BasicJsonType> + using iter_impl = ::nlohmann::detail::iter_impl<BasicJsonType>; + template<typename Iterator> + using iteration_proxy = ::nlohmann::detail::iteration_proxy<Iterator>; + template<typename Base> using json_reverse_iterator = ::nlohmann::detail::json_reverse_iterator<Base>; + + template<typename CharType> + using output_adapter_t = ::nlohmann::detail::output_adapter_t<CharType>; + + using binary_reader = ::nlohmann::detail::binary_reader<basic_json>; + template<typename CharType> using binary_writer = ::nlohmann::detail::binary_writer<basic_json, CharType>; + + using serializer = ::nlohmann::detail::serializer<basic_json>; public: - // forward declarations - template<typename Base> class json_reverse_iterator; - class json_pointer; + using value_t = detail::value_t; + /// @copydoc nlohmann::json_pointer + using json_pointer = ::nlohmann::json_pointer; + template<typename T, typename SFINAE> + using json_serializer = JSONSerializer<T, SFINAE>; + /// helper type for initializer lists of basic_json values + using initializer_list_t = std::initializer_list<detail::json_ref<basic_json>>; + + //////////////// + // exceptions // + //////////////// + + /// @name exceptions + /// Classes to implement user-defined exceptions. + /// @{ + + /// @copydoc detail::exception + using exception = detail::exception; + /// @copydoc detail::parse_error + using parse_error = detail::parse_error; + /// @copydoc detail::invalid_iterator + using invalid_iterator = detail::invalid_iterator; + /// @copydoc detail::type_error + using type_error = detail::type_error; + /// @copydoc detail::out_of_range + using out_of_range = detail::out_of_range; + /// @copydoc detail::other_error + using other_error = detail::other_error; + + /// @} + ///////////////////// // container types // ///////////////////// /// @name container types + /// The canonic container types to use @ref basic_json like any other STL + /// container. /// @{ /// the type of elements in a basic_json container @@ -231,9 +7465,9 @@ class basic_json using const_pointer = typename std::allocator_traits<allocator_type>::const_pointer; /// an iterator for a basic_json container - class iterator; + using iterator = iter_impl<basic_json>; /// a const iterator for a basic_json container - class const_iterator; + using const_iterator = iter_impl<const basic_json>; /// a reverse iterator for a basic_json container using reverse_iterator = json_reverse_iterator<typename basic_json::iterator>; /// a const reverse iterator for a basic_json container @@ -250,14 +7484,102 @@ class basic_json return allocator_type(); } + /*! + @brief returns version information on the library + + This function returns a JSON object with information about the library, + including the version number and information on the platform and compiler. + + @return JSON object holding version information + key | description + ----------- | --------------- + `compiler` | Information on the used compiler. It is an object with the following keys: `c++` (the used C++ standard), `family` (the compiler family; possible values are `clang`, `icc`, `gcc`, `ilecpp`, `msvc`, `pgcpp`, `sunpro`, and `unknown`), and `version` (the compiler version). + `copyright` | The copyright line for the library as string. + `name` | The name of the library as string. + `platform` | The used platform as string. Possible values are `win32`, `linux`, `apple`, `unix`, and `unknown`. + `url` | The URL of the project as string. + `version` | The version of the library. It is an object with the following keys: `major`, `minor`, and `patch` as defined by [Semantic Versioning](http://semver.org), and `string` (the version string). + + @liveexample{The following code shows an example output of the `meta()` + function.,meta} + + @exceptionsafety Strong guarantee: if an exception is thrown, there are no + changes to any JSON value. + + @complexity Constant. + + @since 2.1.0 + */ + static basic_json meta() + { + basic_json result; + + result["copyright"] = "(C) 2013-2017 Niels Lohmann"; + result["name"] = "JSON for Modern C++"; + result["url"] = "https://github.com/nlohmann/json"; + result["version"] = + { + {"string", "3.0.1"}, {"major", 3}, {"minor", 0}, {"patch", 1} + }; + +#ifdef _WIN32 + result["platform"] = "win32"; +#elif defined __linux__ + result["platform"] = "linux"; +#elif defined __APPLE__ + result["platform"] = "apple"; +#elif defined __unix__ + result["platform"] = "unix"; +#else + result["platform"] = "unknown"; +#endif + +#if defined(__ICC) || defined(__INTEL_COMPILER) + result["compiler"] = {{"family", "icc"}, {"version", __INTEL_COMPILER}}; +#elif defined(__clang__) + result["compiler"] = {{"family", "clang"}, {"version", __clang_version__}}; +#elif defined(__GNUC__) || defined(__GNUG__) + result["compiler"] = {{"family", "gcc"}, {"version", std::to_string(__GNUC__) + "." + std::to_string(__GNUC_MINOR__) + "." + std::to_string(__GNUC_PATCHLEVEL__)}}; +#elif defined(__HP_cc) || defined(__HP_aCC) + result["compiler"] = "hp" +#elif defined(__IBMCPP__) + result["compiler"] = {{"family", "ilecpp"}, {"version", __IBMCPP__}}; +#elif defined(_MSC_VER) + result["compiler"] = {{"family", "msvc"}, {"version", _MSC_VER}}; +#elif defined(__PGI) + result["compiler"] = {{"family", "pgcpp"}, {"version", __PGI}}; +#elif defined(__SUNPRO_CC) + result["compiler"] = {{"family", "sunpro"}, {"version", __SUNPRO_CC}}; +#else + result["compiler"] = {{"family", "unknown"}, {"version", "unknown"}}; +#endif + +#ifdef __cplusplus + result["compiler"]["c++"] = std::to_string(__cplusplus); +#else + result["compiler"]["c++"] = "unknown"; +#endif + return result; + } + /////////////////////////// // JSON value data types // /////////////////////////// /// @name JSON value data types + /// The data types to store a JSON value. These types are derived from + /// the template arguments passed to class @ref basic_json. /// @{ +#if defined(JSON_HAS_CPP_14) + // Use transparent comparator if possible, combined with perfect forwarding + // on find() and count() calls prevents unnecessary string construction. + using object_comparator_t = std::less<>; +#else + using object_comparator_t = std::less<StringType>; +#endif + /*! @brief a type for an object @@ -318,7 +7640,7 @@ class basic_json [RFC 7159](http://rfc7159.net/rfc7159) specifies: > An implementation may set limits on the maximum depth of nesting. - In this class, the object's limit of nesting is not constraint explicitly. + In this class, the object's limit of nesting is not explicitly constrained. However, a maximum depth of nesting may be introduced by the compiler or runtime environment. A theoretical limit can be queried by calling the @ref max_size function of a JSON object. @@ -343,7 +7665,7 @@ class basic_json */ using object_t = ObjectType<StringType, basic_json, - std::less<StringType>, + object_comparator_t, AllocatorType<std::pair<const StringType, basic_json>>>; @@ -358,7 +7680,7 @@ class basic_json @tparam ArrayType container type to store arrays (e.g., `std::vector` or `std::list`) - @tparam AllocatorType allocator to use for arrays (e.g., `std::allocator`) + @tparam AllocatorType allocator to use for arrays (e.g., `std::allocator`) #### Default type @@ -377,7 +7699,7 @@ class basic_json [RFC 7159](http://rfc7159.net/rfc7159) specifies: > An implementation may set limits on the maximum depth of nesting. - In this class, the array's limit of nesting is not constraint explicitly. + In this class, the array's limit of nesting is not explicitly constrained. However, a maximum depth of nesting may be introduced by the compiler or runtime environment. A theoretical limit can be queried by calling the @ref max_size function of a JSON array. @@ -415,6 +7737,12 @@ class basic_json std::string @endcode + #### Encoding + + Strings are stored in UTF-8 encoding. Therefore, functions like + `std::string::size()` or `std::string::length()` return the number of + bytes in the string rather than the number of characters or glyphs. + #### String comparison [RFC 7159](http://rfc7159.net/rfc7159) states: @@ -595,15 +7923,14 @@ class basic_json > that implementations will agree exactly on their numeric values. As this range is a subrange (when considered in conjunction with the - number_integer_t type) of the exactly supported range [0, UINT64_MAX], this - class's integer type is interoperable. + number_integer_t type) of the exactly supported range [0, UINT64_MAX], + this class's integer type is interoperable. #### Storage Integer number values are stored directly inside a @ref basic_json type. @sa @ref number_float_t -- type for number values (floating-point) - @sa @ref number_integer_t -- type for number values (integer) @since version 2.0.0 @@ -680,115 +8007,22 @@ class basic_json /// @} - - /////////////////////////// - // JSON type enumeration // - /////////////////////////// - - /*! - @brief the JSON type enumeration - - This enumeration collects the different JSON types. It is internally used - to distinguish the stored values, and the functions @ref is_null(), @ref - is_object(), @ref is_array(), @ref is_string(), @ref is_boolean(), @ref - is_number(), and @ref is_discarded() rely on it. - - @since version 1.0.0 - */ - enum class value_t : uint8_t - { - null, ///< null value - object, ///< object (unordered set of name/value pairs) - array, ///< array (ordered collection of values) - string, ///< string value - boolean, ///< boolean value - number_integer, ///< number value (integer) - number_unsigned, ///< number value (unsigned integer) - number_float, ///< number value (floating-point) - discarded ///< discarded by the the parser callback function - }; - - private: - /*! - @brief a type to hold JSON type information - - This bitfield type holds information about JSON types. It is internally - used to hold the basic JSON type enumeration, as well as additional - information in the case of values that have been parsed from a string - including whether of not it was created directly or parsed, and in the - case of floating point numbers the number of significant figures in the - original representaiton and if it was in exponential form, if a '+' was - included in the exponent and the capitilization of the exponent marker. - The sole purpose of this information is to permit accurate round trips. - - @since version 2.0.0 - */ - union type_data_t - { - struct - { - /// the type of the value (@ref value_t) - uint16_t type : 4; - /// whether the number was parsed from a string - uint16_t parsed : 1; - /// whether parsed number contained an exponent ('e'/'E') - uint16_t has_exp : 1; - /// whether parsed number contained a plus in the exponent - uint16_t exp_plus : 1; - /// whether parsed number's exponent was capitalized ('E') - uint16_t exp_cap : 1; - /// the number of figures for a parsed number - uint16_t precision : 8; - } bits; - uint16_t data; - - /// return the type as value_t - operator value_t() const - { - return static_cast<value_t>(bits.type); - } - - /// test type for equality (ignore other fields) - bool operator==(const value_t& rhs) const - { - return static_cast<value_t>(bits.type) == rhs; - } - - /// assignment - type_data_t& operator=(value_t rhs) - { - bits.type = static_cast<uint16_t>(rhs) & 15; // avoid overflow - return *this; - } - - /// construct from value_t - type_data_t(value_t t) noexcept - { - *reinterpret_cast<uint16_t*>(this) = 0; - bits.type = static_cast<uint16_t>(t) & 15; // avoid overflow - } - - /// default constructor - type_data_t() noexcept - { - data = 0; - bits.type = reinterpret_cast<uint16_t>(value_t::null); - } - }; - /// helper for exception-safe object creation template<typename T, typename... Args> static T* create(Args&& ... args) { AllocatorType<T> alloc; + using AllocatorTraits = std::allocator_traits<AllocatorType<T>>; + auto deleter = [&](T * object) { - alloc.deallocate(object, 1); + AllocatorTraits::deallocate(alloc, object, 1); }; - std::unique_ptr<T, decltype(deleter)> object(alloc.allocate(1), deleter); - alloc.construct(object.get(), std::forward<Args>(args)...); + std::unique_ptr<T, decltype(deleter)> object(AllocatorTraits::allocate(alloc, 1), deleter); + AllocatorTraits::construct(alloc, object.get(), std::forward<Args>(args)...); + assert(object != nullptr); return object.release(); } @@ -799,7 +8033,24 @@ class basic_json /*! @brief a JSON value - The actual storage for a JSON value of the @ref basic_json class. + The actual storage for a JSON value of the @ref basic_json class. This + union combines the different storage types for the JSON value types + defined in @ref value_t. + + JSON type | value_t type | used type + --------- | --------------- | ------------------------ + object | object | pointer to @ref object_t + array | array | pointer to @ref array_t + string | string | pointer to @ref string_t + boolean | boolean | @ref boolean_t + number | number_integer | @ref number_integer_t + number | number_unsigned | @ref number_unsigned_t + number | number_float | @ref number_float_t + null | null | *no value is stored* + + @note Variable-length types (objects, arrays, and strings) are stored as + pointers. The size of the union should not exceed 64 bits if the default + value types are used. @since version 1.0.0 */ @@ -877,8 +8128,19 @@ class basic_json break; } + case value_t::null: + { + object = nullptr; // silence warning, see #821 + break; + } + default: { + object = nullptr; // silence warning, see #821 + if (JSON_UNLIKELY(t == value_t::null)) + { + JSON_THROW(other_error::create(500, "961c151d2e87f2686a955a9be24d316f1362bf21 3.0.1")); // LCOV_EXCL_LINE + } break; } } @@ -890,19 +8152,87 @@ class basic_json string = create<string_t>(value); } + /// constructor for rvalue strings + json_value(string_t&& value) + { + string = create<string_t>(std::move(value)); + } + /// constructor for objects json_value(const object_t& value) { object = create<object_t>(value); } + /// constructor for rvalue objects + json_value(object_t&& value) + { + object = create<object_t>(std::move(value)); + } + /// constructor for arrays json_value(const array_t& value) { array = create<array_t>(value); } + + /// constructor for rvalue arrays + json_value(array_t&& value) + { + array = create<array_t>(std::move(value)); + } + + void destroy(value_t t) + { + switch (t) + { + case value_t::object: + { + AllocatorType<object_t> alloc; + std::allocator_traits<decltype(alloc)>::destroy(alloc, object); + std::allocator_traits<decltype(alloc)>::deallocate(alloc, object, 1); + break; + } + + case value_t::array: + { + AllocatorType<array_t> alloc; + std::allocator_traits<decltype(alloc)>::destroy(alloc, array); + std::allocator_traits<decltype(alloc)>::deallocate(alloc, array, 1); + break; + } + + case value_t::string: + { + AllocatorType<string_t> alloc; + std::allocator_traits<decltype(alloc)>::destroy(alloc, string); + std::allocator_traits<decltype(alloc)>::deallocate(alloc, string, 1); + break; + } + + default: + { + break; + } + } + } }; + /*! + @brief checks the class invariants + + This function asserts the class invariants. It needs to be called at the + end of every constructor to make sure that created objects respect the + invariant. Furthermore, it has to be called each time the type of a JSON + value is changed, because the invariant expresses a relationship between + @a m_type and @a m_value. + */ + void assert_invariant() const + { + assert(m_type != value_t::object or m_value.object != nullptr); + assert(m_type != value_t::array or m_value.array != nullptr); + assert(m_type != value_t::string or m_value.string != nullptr); + } public: ////////////////////////// @@ -910,39 +8240,31 @@ class basic_json ////////////////////////// /*! - @brief JSON callback events + @brief parser event types - This enumeration lists the parser events that can trigger calling a - callback function of type @ref parser_callback_t during parsing. + The parser callback distinguishes the following events: + - `object_start`: the parser read `{` and started to process a JSON object + - `key`: the parser read a key of a value in an object + - `object_end`: the parser read `}` and finished processing a JSON object + - `array_start`: the parser read `[` and started to process a JSON array + - `array_end`: the parser read `]` and finished processing a JSON array + - `value`: the parser finished reading a JSON value - @since version 1.0.0 + @image html callback_events.png "Example when certain parse events are triggered" + + @sa @ref parser_callback_t for more information and examples */ - enum class parse_event_t : uint8_t - { - /// the parser read `{` and started to process a JSON object - object_start, - /// the parser read `}` and finished processing a JSON object - object_end, - /// the parser read `[` and started to process a JSON array - array_start, - /// the parser read `]` and finished processing a JSON array - array_end, - /// the parser read a key of a value in an object - key, - /// the parser finished reading a JSON value - value - }; + using parse_event_t = typename parser::parse_event_t; /*! @brief per-element parser callback type With a parser callback function, the result of parsing a JSON text can be - influenced. When passed to @ref parse(std::istream&, parser_callback_t) or - @ref parse(const string_t&, parser_callback_t), it is called on certain - events (passed as @ref parse_event_t via parameter @a event) with a set - recursion depth @a depth and context JSON value @a parsed. The return - value of the callback function is a boolean indicating whether the element - that emitted the callback shall be kept or not. + influenced. When passed to @ref parse, it is called on certain events + (passed as @ref parse_event_t via parameter @a event) with a set recursion + depth @a depth and context JSON value @a parsed. The return value of the + callback function is a boolean indicating whether the element that emitted + the callback shall be kept or not. We distinguish six scenarios (determined by the event type) in which the callback function can be called. The following table describes the values @@ -957,6 +8279,8 @@ class basic_json parse_event_t::array_end | the parser read `]` and finished processing a JSON array | depth of the parent of the JSON array | the parsed JSON array parse_event_t::value | the parser finished reading a JSON value | depth of the value | the parsed JSON value + @image html callback_events.png "Example when certain parse events are triggered" + Discarding a value (i.e., returning `false`) has different effects depending on the context in which function was called: @@ -977,12 +8301,11 @@ class basic_json should be kept (`true`) or not (`false`). In the latter case, it is either skipped completely or replaced by an empty discarded object. - @sa @ref parse(std::istream&, parser_callback_t) or - @ref parse(const string_t&, parser_callback_t) for examples + @sa @ref parse for examples @since version 1.0.0 */ - using parser_callback_t = std::function<bool(int depth, parse_event_t event, basic_json& parsed)>; + using parser_callback_t = typename parser::parser_callback_t; ////////////////// @@ -990,6 +8313,8 @@ class basic_json ////////////////// /// @name constructors and destructors + /// Constructors of class @ref basic_json, copy/move constructor, copy + /// assignment, static functions creating objects, and the destructor. /// @{ /*! @@ -1007,66 +8332,31 @@ class basic_json object | `{}` array | `[]` - @param[in] value_type the type of the value to create + @param[in] v the type of the value to create @complexity Constant. - @throw std::bad_alloc if allocation for object, array, or string value - fails + @exceptionsafety Strong guarantee: if an exception is thrown, there are no + changes to any JSON value. @liveexample{The following code shows the constructor for different @ref value_t values,basic_json__value_t} - @sa @ref basic_json(std::nullptr_t) -- create a `null` value - @sa @ref basic_json(boolean_t value) -- create a boolean value - @sa @ref basic_json(const string_t&) -- create a string value - @sa @ref basic_json(const object_t&) -- create a object value - @sa @ref basic_json(const array_t&) -- create a array value - @sa @ref basic_json(const number_float_t) -- create a number - (floating-point) value - @sa @ref basic_json(const number_integer_t) -- create a number (integer) - value - @sa @ref basic_json(const number_unsigned_t) -- create a number (unsigned) - value + @sa @ref clear() -- restores the postcondition of this constructor @since version 1.0.0 */ - basic_json(const value_t value_type) - : m_type(value_type), m_value(value_type) - {} - - /*! - @brief create a null object (implicitly) - - Create a `null` JSON value. This is the implicit version of the `null` - value constructor as it takes no parameters. - - @complexity Constant. - - @exceptionsafety No-throw guarantee: this constructor never throws - exceptions. - - @requirement This function helps `basic_json` satisfying the - [Container](http://en.cppreference.com/w/cpp/concept/Container) - requirements: - - The complexity is constant. - - As postcondition, it holds: `basic_json().empty() == true`. - - @liveexample{The following code shows the constructor for a `null` JSON - value.,basic_json} - - @sa @ref basic_json(std::nullptr_t) -- create a `null` value - - @since version 1.0.0 - */ - basic_json() = default; + basic_json(const value_t v) + : m_type(v), m_value(v) + { + assert_invariant(); + } /*! - @brief create a null object (explicitly) + @brief create a null object - Create a `null` JSON value. This is the explicitly version of the `null` - value constructor as it takes a null pointer as parameter. It allows to - create `null` values by explicitly assigning a `nullptr` to a JSON value. + Create a `null` JSON value. It either takes a null pointer as parameter + (explicitly creating `null`) or no parameter (implicitly creating `null`). The passed null pointer itself is not read -- it is only used to choose the right constructor. @@ -1075,480 +8365,88 @@ class basic_json @exceptionsafety No-throw guarantee: this constructor never throws exceptions. - @liveexample{The following code shows the constructor with null pointer - parameter.,basic_json__nullptr_t} - - @sa @ref basic_json() -- default constructor (implicitly creating a `null` - value) + @liveexample{The following code shows the constructor with and without a + null pointer parameter.,basic_json__nullptr_t} @since version 1.0.0 */ - basic_json(std::nullptr_t) noexcept + basic_json(std::nullptr_t = nullptr) noexcept : basic_json(value_t::null) - {} - - /*! - @brief create an object (explicit) - - Create an object JSON value with a given content. - - @param[in] val a value for the object - - @complexity Linear in the size of the passed @a val. - - @throw std::bad_alloc if allocation for object value fails - - @liveexample{The following code shows the constructor with an @ref - object_t parameter.,basic_json__object_t} - - @sa @ref basic_json(const CompatibleObjectType&) -- create an object value - from a compatible STL container - - @since version 1.0.0 - */ - basic_json(const object_t& val) - : m_type(value_t::object), m_value(val) - {} - - /*! - @brief create an object (implicit) - - Create an object JSON value with a given content. This constructor allows - any type @a CompatibleObjectType that can be used to construct values of - type @ref object_t. - - @tparam CompatibleObjectType An object type whose `key_type` and - `value_type` is compatible to @ref object_t. Examples include `std::map`, - `std::unordered_map`, `std::multimap`, and `std::unordered_multimap` with - a `key_type` of `std::string`, and a `value_type` from which a @ref - basic_json value can be constructed. - - @param[in] val a value for the object - - @complexity Linear in the size of the passed @a val. - - @throw std::bad_alloc if allocation for object value fails - - @liveexample{The following code shows the constructor with several - compatible object type parameters.,basic_json__CompatibleObjectType} - - @sa @ref basic_json(const object_t&) -- create an object value - - @since version 1.0.0 - */ - template <class CompatibleObjectType, typename - std::enable_if< - std::is_constructible<typename object_t::key_type, typename CompatibleObjectType::key_type>::value and - std::is_constructible<basic_json, typename CompatibleObjectType::mapped_type>::value, int>::type - = 0> - basic_json(const CompatibleObjectType& val) - : m_type(value_t::object) { - using std::begin; - using std::end; - m_value.object = create<object_t>(begin(val), end(val)); + assert_invariant(); } /*! - @brief create an array (explicit) - - Create an array JSON value with a given content. - - @param[in] val a value for the array - - @complexity Linear in the size of the passed @a val. - - @throw std::bad_alloc if allocation for array value fails + @brief create a JSON value - @liveexample{The following code shows the constructor with an @ref array_t - parameter.,basic_json__array_t} + This is a "catch all" constructor for all compatible JSON types; that is, + types for which a `to_json()` method exists. The constructor forwards the + parameter @a val to that method (to `json_serializer<U>::to_json` method + with `U = uncvref_t<CompatibleType>`, to be exact). - @sa @ref basic_json(const CompatibleArrayType&) -- create an array value - from a compatible STL containers + Template type @a CompatibleType includes, but is not limited to, the + following types: + - **arrays**: @ref array_t and all kinds of compatible containers such as + `std::vector`, `std::deque`, `std::list`, `std::forward_list`, + `std::array`, `std::valarray`, `std::set`, `std::unordered_set`, + `std::multiset`, and `std::unordered_multiset` with a `value_type` from + which a @ref basic_json value can be constructed. + - **objects**: @ref object_t and all kinds of compatible associative + containers such as `std::map`, `std::unordered_map`, `std::multimap`, + and `std::unordered_multimap` with a `key_type` compatible to + @ref string_t and a `value_type` from which a @ref basic_json value can + be constructed. + - **strings**: @ref string_t, string literals, and all compatible string + containers can be used. + - **numbers**: @ref number_integer_t, @ref number_unsigned_t, + @ref number_float_t, and all convertible number types such as `int`, + `size_t`, `int64_t`, `float` or `double` can be used. + - **boolean**: @ref boolean_t / `bool` can be used. - @since version 1.0.0 - */ - basic_json(const array_t& val) - : m_type(value_t::array), m_value(val) - {} + See the examples below. - /*! - @brief create an array (implicit) - - Create an array JSON value with a given content. This constructor allows - any type @a CompatibleArrayType that can be used to construct values of - type @ref array_t. + @tparam CompatibleType a type such that: + - @a CompatibleType is not derived from `std::istream`, + - @a CompatibleType is not @ref basic_json (to avoid hijacking copy/move + constructors), + - @a CompatibleType is not a @ref basic_json nested type (e.g., + @ref json_pointer, @ref iterator, etc ...) + - @ref @ref json_serializer<U> has a + `to_json(basic_json_t&, CompatibleType&&)` method - @tparam CompatibleArrayType An object type whose `value_type` is - compatible to @ref array_t. Examples include `std::vector`, `std::deque`, - `std::list`, `std::forward_list`, `std::array`, `std::set`, - `std::unordered_set`, `std::multiset`, and `unordered_multiset` with a - `value_type` from which a @ref basic_json value can be constructed. + @tparam U = `uncvref_t<CompatibleType>` - @param[in] val a value for the array + @param[in] val the value to be forwarded to the respective constructor - @complexity Linear in the size of the passed @a val. + @complexity Usually linear in the size of the passed @a val, also + depending on the implementation of the called `to_json()` + method. - @throw std::bad_alloc if allocation for array value fails + @exceptionsafety Depends on the called constructor. For types directly + supported by the library (i.e., all types for which no `to_json()` function + was provided), strong guarantee holds: if an exception is thrown, there are + no changes to any JSON value. @liveexample{The following code shows the constructor with several - compatible array type parameters.,basic_json__CompatibleArrayType} - - @sa @ref basic_json(const array_t&) -- create an array value + compatible types.,basic_json__CompatibleType} - @since version 1.0.0 + @since version 2.1.0 */ - template <class CompatibleArrayType, typename - std::enable_if< - not std::is_same<CompatibleArrayType, typename basic_json_t::iterator>::value and - not std::is_same<CompatibleArrayType, typename basic_json_t::const_iterator>::value and - not std::is_same<CompatibleArrayType, typename basic_json_t::reverse_iterator>::value and - not std::is_same<CompatibleArrayType, typename basic_json_t::const_reverse_iterator>::value and - not std::is_same<CompatibleArrayType, typename array_t::iterator>::value and - not std::is_same<CompatibleArrayType, typename array_t::const_iterator>::value and - std::is_constructible<basic_json, typename CompatibleArrayType::value_type>::value, int>::type - = 0> - basic_json(const CompatibleArrayType& val) - : m_type(value_t::array) + template<typename CompatibleType, typename U = detail::uncvref_t<CompatibleType>, + detail::enable_if_t<not std::is_base_of<std::istream, U>::value and + not std::is_same<U, basic_json_t>::value and + not detail::is_basic_json_nested_type< + basic_json_t, U>::value and + detail::has_to_json<basic_json, U>::value, + int> = 0> + basic_json(CompatibleType && val) noexcept(noexcept(JSONSerializer<U>::to_json( + std::declval<basic_json_t&>(), std::forward<CompatibleType>(val)))) { - using std::begin; - using std::end; - m_value.array = create<array_t>(begin(val), end(val)); + JSONSerializer<U>::to_json(*this, std::forward<CompatibleType>(val)); + assert_invariant(); } /*! - @brief create a string (explicit) - - Create an string JSON value with a given content. - - @param[in] val a value for the string - - @complexity Linear in the size of the passed @a val. - - @throw std::bad_alloc if allocation for string value fails - - @liveexample{The following code shows the constructor with an @ref - string_t parameter.,basic_json__string_t} - - @sa @ref basic_json(const typename string_t::value_type*) -- create a - string value from a character pointer - @sa @ref basic_json(const CompatibleStringType&) -- create a string value - from a compatible string container - - @since version 1.0.0 - */ - basic_json(const string_t& val) - : m_type(value_t::string), m_value(val) - {} - - /*! - @brief create a string (explicit) - - Create a string JSON value with a given content. - - @param[in] val a literal value for the string - - @complexity Linear in the size of the passed @a val. - - @throw std::bad_alloc if allocation for string value fails - - @liveexample{The following code shows the constructor with string literal - parameter.,basic_json__string_t_value_type} - - @sa @ref basic_json(const string_t&) -- create a string value - @sa @ref basic_json(const CompatibleStringType&) -- create a string value - from a compatible string container - - @since version 1.0.0 - */ - basic_json(const typename string_t::value_type* val) - : basic_json(string_t(val)) - {} - - /*! - @brief create a string (implicit) - - Create a string JSON value with a given content. - - @param[in] val a value for the string - - @tparam CompatibleStringType an string type which is compatible to @ref - string_t, for instance `std::string`. - - @complexity Linear in the size of the passed @a val. - - @throw std::bad_alloc if allocation for string value fails - - @liveexample{The following code shows the construction of a string value - from a compatible type.,basic_json__CompatibleStringType} - - @sa @ref basic_json(const string_t&) -- create a string value - @sa @ref basic_json(const typename string_t::value_type*) -- create a - string value from a character pointer - - @since version 1.0.0 - */ - template <class CompatibleStringType, typename - std::enable_if< - std::is_constructible<string_t, CompatibleStringType>::value, int>::type - = 0> - basic_json(const CompatibleStringType& val) - : basic_json(string_t(val)) - {} - - /*! - @brief create a boolean (explicit) - - Creates a JSON boolean type from a given value. - - @param[in] val a boolean value to store - - @complexity Constant. - - @liveexample{The example below demonstrates boolean - values.,basic_json__boolean_t} - - @since version 1.0.0 - */ - basic_json(boolean_t val) noexcept - : m_type(value_t::boolean), m_value(val) - {} - - /*! - @brief create an integer number (explicit) - - Create an integer number JSON value with a given content. - - @tparam T A helper type to remove this function via SFINAE in case @ref - number_integer_t is the same as `int`. In this case, this constructor - would have the same signature as @ref basic_json(const int value). Note - the helper type @a T is not visible in this constructor's interface. - - @param[in] val an integer to create a JSON number from - - @complexity Constant. - - @liveexample{The example below shows the construction of an integer - number value.,basic_json__number_integer_t} - - @sa @ref basic_json(const int) -- create a number value (integer) - @sa @ref basic_json(const CompatibleNumberIntegerType) -- create a number - value (integer) from a compatible number type - - @since version 1.0.0 - */ - template<typename T, - typename std::enable_if< - not (std::is_same<T, int>::value) - and std::is_same<T, number_integer_t>::value - , int>::type - = 0> - basic_json(const number_integer_t val) noexcept - : m_type(value_t::number_integer), m_value(val) - {} - - /*! - @brief create an integer number from an enum type (explicit) - - Create an integer number JSON value with a given content. - - @param[in] val an integer to create a JSON number from - - @note This constructor allows to pass enums directly to a constructor. As - C++ has no way of specifying the type of an anonymous enum explicitly, we - can only rely on the fact that such values implicitly convert to int. As - int may already be the same type of number_integer_t, we may need to - switch off the constructor @ref basic_json(const number_integer_t). - - @complexity Constant. - - @liveexample{The example below shows the construction of an integer - number value from an anonymous enum.,basic_json__const_int} - - @sa @ref basic_json(const number_integer_t) -- create a number value - (integer) - @sa @ref basic_json(const CompatibleNumberIntegerType) -- create a number - value (integer) from a compatible number type - - @since version 1.0.0 - */ - basic_json(const int val) noexcept - : m_type(value_t::number_integer), - m_value(static_cast<number_integer_t>(val)) - {} - - /*! - @brief create an integer number (implicit) - - Create an integer number JSON value with a given content. This constructor - allows any type @a CompatibleNumberIntegerType that can be used to - construct values of type @ref number_integer_t. - - @tparam CompatibleNumberIntegerType An integer type which is compatible to - @ref number_integer_t. Examples include the types `int`, `int32_t`, - `long`, and `short`. - - @param[in] val an integer to create a JSON number from - - @complexity Constant. - - @liveexample{The example below shows the construction of several integer - number values from compatible - types.,basic_json__CompatibleIntegerNumberType} - - @sa @ref basic_json(const number_integer_t) -- create a number value - (integer) - @sa @ref basic_json(const int) -- create a number value (integer) - - @since version 1.0.0 - */ - template<typename CompatibleNumberIntegerType, typename - std::enable_if< - std::is_constructible<number_integer_t, CompatibleNumberIntegerType>::value and - std::numeric_limits<CompatibleNumberIntegerType>::is_integer and - std::numeric_limits<CompatibleNumberIntegerType>::is_signed, - CompatibleNumberIntegerType>::type - = 0> - basic_json(const CompatibleNumberIntegerType val) noexcept - : m_type(value_t::number_integer), - m_value(static_cast<number_integer_t>(val)) - {} - - /*! - @brief create an unsigned integer number (explicit) - - Create an unsigned integer number JSON value with a given content. - - @tparam T helper type to compare number_unsigned_t and unsigned int - (not visible in) the interface. - - @param[in] val an integer to create a JSON number from - - @complexity Constant. - - @sa @ref basic_json(const CompatibleNumberUnsignedType) -- create a number - value (unsigned integer) from a compatible number type - - @since version 2.0.0 - */ - template<typename T, - typename std::enable_if< - not (std::is_same<T, int>::value) - and std::is_same<T, number_unsigned_t>::value - , int>::type - = 0> - basic_json(const number_unsigned_t val) noexcept - : m_type(value_t::number_unsigned), m_value(val) - {} - - /*! - @brief create an unsigned number (implicit) - - Create an unsigned number JSON value with a given content. This - constructor allows any type @a CompatibleNumberUnsignedType that can be - used to construct values of type @ref number_unsigned_t. - - @tparam CompatibleNumberUnsignedType An integer type which is compatible - to @ref number_unsigned_t. Examples may include the types `unsigned int`, - `uint32_t`, or `unsigned short`. - - @param[in] val an unsigned integer to create a JSON number from - - @complexity Constant. - - @sa @ref basic_json(const number_unsigned_t) -- create a number value - (unsigned) - - @since version 2.0.0 - */ - template <typename CompatibleNumberUnsignedType, typename - std::enable_if < - std::is_constructible<number_unsigned_t, CompatibleNumberUnsignedType>::value and - std::numeric_limits<CompatibleNumberUnsignedType>::is_integer and - not std::numeric_limits<CompatibleNumberUnsignedType>::is_signed, - CompatibleNumberUnsignedType>::type - = 0> - basic_json(const CompatibleNumberUnsignedType val) noexcept - : m_type(value_t::number_unsigned), - m_value(static_cast<number_unsigned_t>(val)) - {} - - /*! - @brief create a floating-point number (explicit) - - Create a floating-point number JSON value with a given content. - - @param[in] val a floating-point value to create a JSON number from - - @note [RFC 7159](http://www.rfc-editor.org/rfc/rfc7159.txt), section 6 - disallows NaN values: - > Numeric values that cannot be represented in the grammar below (such as - > Infinity and NaN) are not permitted. - In case the parameter @a val is not a number, a JSON null value is - created instead. - - @complexity Constant. - - @liveexample{The following example creates several floating-point - values.,basic_json__number_float_t} - - @sa @ref basic_json(const CompatibleNumberFloatType) -- create a number - value (floating-point) from a compatible number type - - @since version 1.0.0 - */ - basic_json(const number_float_t val) noexcept - : m_type(value_t::number_float), m_value(val) - { - // replace infinity and NAN by null - if (not std::isfinite(val)) - { - m_type = value_t::null; - m_value = json_value(); - } - } - - /*! - @brief create an floating-point number (implicit) - - Create an floating-point number JSON value with a given content. This - constructor allows any type @a CompatibleNumberFloatType that can be used - to construct values of type @ref number_float_t. - - @tparam CompatibleNumberFloatType A floating-point type which is - compatible to @ref number_float_t. Examples may include the types `float` - or `double`. - - @param[in] val a floating-point to create a JSON number from - - @note [RFC 7159](http://www.rfc-editor.org/rfc/rfc7159.txt), section 6 - disallows NaN values: - > Numeric values that cannot be represented in the grammar below (such as - > Infinity and NaN) are not permitted. - In case the parameter @a val is not a number, a JSON null value is - created instead. - - @complexity Constant. - - @liveexample{The example below shows the construction of several - floating-point number values from compatible - types.,basic_json__CompatibleNumberFloatType} - - @sa @ref basic_json(const number_float_t) -- create a number value - (floating-point) - - @since version 1.0.0 - */ - template<typename CompatibleNumberFloatType, typename = typename - std::enable_if< - std::is_constructible<number_float_t, CompatibleNumberFloatType>::value and - std::is_floating_point<CompatibleNumberFloatType>::value>::type - > - basic_json(const CompatibleNumberFloatType val) noexcept - : basic_json(number_float_t(val)) - {} - - /*! @brief create a container (array or object) from an initializer list Creates a JSON value of type array or object from the passed initializer @@ -1558,29 +8456,29 @@ class basic_json 1. If the list is empty, an empty JSON object value `{}` is created. 2. If the list consists of pairs whose first element is a string, a JSON - object value is created where the first elements of the pairs are treated - as keys and the second elements are as values. + object value is created where the first elements of the pairs are + treated as keys and the second elements are as values. 3. In all other cases, an array is created. The rules aim to create the best fit between a C++ initializer list and JSON values. The rationale is as follows: 1. The empty initializer list is written as `{}` which is exactly an empty - JSON object. - 2. C++ has now way of describing mapped types other than to list a list of - pairs. As JSON requires that keys must be of type string, rule 2 is the - weakest constraint one can pose on initializer lists to interpret them as - an object. + JSON object. + 2. C++ has no way of describing mapped types other than to list a list of + pairs. As JSON requires that keys must be of type string, rule 2 is the + weakest constraint one can pose on initializer lists to interpret them + as an object. 3. In all other cases, the initializer list could not be interpreted as - JSON object type, so interpreting it as JSON array type is safe. + JSON object type, so interpreting it as JSON array type is safe. With the rules described above, the following JSON values cannot be expressed by an initializer list: - - the empty array (`[]`): use @ref array(std::initializer_list<basic_json>) + - the empty array (`[]`): use @ref array(initializer_list_t) with an empty initializer list in this case - arrays whose elements satisfy rule 2: use @ref - array(std::initializer_list<basic_json>) with the same initializer list + array(initializer_list_t) with the same initializer list in this case @note When used without parentheses around an empty initializer list, @ref @@ -1592,51 +8490,47 @@ class basic_json @param[in] type_deduction internal parameter; when set to `true`, the type of the JSON value is deducted from the initializer list @a init; when set to `false`, the type provided via @a manual_type is forced. This mode is - used by the functions @ref array(std::initializer_list<basic_json>) and - @ref object(std::initializer_list<basic_json>). + used by the functions @ref array(initializer_list_t) and + @ref object(initializer_list_t). @param[in] manual_type internal parameter; when @a type_deduction is set to `false`, the created JSON value will use the provided type (only @ref value_t::array and @ref value_t::object are valid); when @a type_deduction is set to `true`, this parameter has no effect - @throw std::domain_error if @a type_deduction is `false`, @a manual_type - is `value_t::object`, but @a init contains an element which is not a pair - whose first element is a string; example: `"cannot create object from - initializer list"` + @throw type_error.301 if @a type_deduction is `false`, @a manual_type is + `value_t::object`, but @a init contains an element which is not a pair + whose first element is a string. In this case, the constructor could not + create an object. If @a type_deduction would have be `true`, an array + would have been created. See @ref object(initializer_list_t) + for an example. @complexity Linear in the size of the initializer list @a init. + @exceptionsafety Strong guarantee: if an exception is thrown, there are no + changes to any JSON value. + @liveexample{The example below shows how JSON values are created from initializer lists.,basic_json__list_init_t} - @sa @ref array(std::initializer_list<basic_json>) -- create a JSON array + @sa @ref array(initializer_list_t) -- create a JSON array value from an initializer list - @sa @ref object(std::initializer_list<basic_json>) -- create a JSON object + @sa @ref object(initializer_list_t) -- create a JSON object value from an initializer list @since version 1.0.0 */ - basic_json(std::initializer_list<basic_json> init, + basic_json(initializer_list_t init, bool type_deduction = true, value_t manual_type = value_t::array) { - // the initializer list could describe an object - bool is_an_object = true; - // check if each element is an array with two elements whose first // element is a string - for (const auto& element : init) + bool is_an_object = std::all_of(init.begin(), init.end(), + [](const detail::json_ref<basic_json>& element_ref) { - if (not element.is_array() or element.size() != 2 - or not element[0].is_string()) - { - // we found an element that makes it impossible to use the - // initializer list as object - is_an_object = false; - break; - } - } + return (element_ref->is_array() and element_ref->size() == 2 and (*element_ref)[0].is_string()); + }); // adjust type if type deduction is not wanted if (not type_deduction) @@ -1648,9 +8542,9 @@ class basic_json } // if object is wanted but impossible, throw an exception - if (manual_type == value_t::object and not is_an_object) + if (JSON_UNLIKELY(manual_type == value_t::object and not is_an_object)) { - throw std::domain_error("cannot create object from initializer list"); + JSON_THROW(type_error::create(301, "cannot create object from initializer list")); } } @@ -1660,19 +8554,22 @@ class basic_json m_type = value_t::object; m_value = value_t::object; - assert(m_value.object != nullptr); - - for (auto& element : init) + std::for_each(init.begin(), init.end(), [this](const detail::json_ref<basic_json>& element_ref) { - m_value.object->emplace(*(element[0].m_value.string), element[1]); - } + auto element = element_ref.moved_or_copied(); + m_value.object->emplace( + std::move(*((*element.m_value.array)[0].m_value.string)), + std::move((*element.m_value.array)[1])); + }); } else { // the initializer list describes an array -> create array m_type = value_t::array; - m_value.array = create<array_t>(init); + m_value.array = create<array_t>(init.begin(), init.end()); } + + assert_invariant(); } /*! @@ -1684,7 +8581,7 @@ class basic_json @note This function is only needed to express two edge cases that cannot be realized with the initializer list constructor (@ref - basic_json(std::initializer_list<basic_json>, bool, value_t)). These cases + basic_json(initializer_list_t, bool, value_t)). These cases are: 1. creating an array whose elements are all pairs whose first element is a string -- in this case, the initializer list constructor would create an @@ -1699,18 +8596,20 @@ class basic_json @complexity Linear in the size of @a init. + @exceptionsafety Strong guarantee: if an exception is thrown, there are no + changes to any JSON value. + @liveexample{The following code shows an example for the `array` function.,array} - @sa @ref basic_json(std::initializer_list<basic_json>, bool, value_t) -- + @sa @ref basic_json(initializer_list_t, bool, value_t) -- create a JSON value from an initializer list - @sa @ref object(std::initializer_list<basic_json>) -- create a JSON object + @sa @ref object(initializer_list_t) -- create a JSON object value from an initializer list @since version 1.0.0 */ - static basic_json array(std::initializer_list<basic_json> init = - std::initializer_list<basic_json>()) + static basic_json array(initializer_list_t init = {}) { return basic_json(init, false, value_t::array); } @@ -1723,34 +8622,37 @@ class basic_json the initializer list is empty, the empty object `{}` is created. @note This function is only added for symmetry reasons. In contrast to the - related function @ref array(std::initializer_list<basic_json>), there are + related function @ref array(initializer_list_t), there are no cases which can only be expressed by this function. That is, any initializer list @a init can also be passed to the initializer list - constructor @ref basic_json(std::initializer_list<basic_json>, bool, - value_t). + constructor @ref basic_json(initializer_list_t, bool, value_t). @param[in] init initializer list to create an object from (optional) @return JSON object value - @throw std::domain_error if @a init is not a pair whose first elements are - strings; thrown by - @ref basic_json(std::initializer_list<basic_json>, bool, value_t) + @throw type_error.301 if @a init is not a list of pairs whose first + elements are strings. In this case, no object can be created. When such a + value is passed to @ref basic_json(initializer_list_t, bool, value_t), + an array would have been created from the passed initializer list @a init. + See example below. @complexity Linear in the size of @a init. + @exceptionsafety Strong guarantee: if an exception is thrown, there are no + changes to any JSON value. + @liveexample{The following code shows an example for the `object` function.,object} - @sa @ref basic_json(std::initializer_list<basic_json>, bool, value_t) -- + @sa @ref basic_json(initializer_list_t, bool, value_t) -- create a JSON value from an initializer list - @sa @ref array(std::initializer_list<basic_json>) -- create a JSON array + @sa @ref array(initializer_list_t) -- create a JSON array value from an initializer list @since version 1.0.0 */ - static basic_json object(std::initializer_list<basic_json> init = - std::initializer_list<basic_json>()) + static basic_json object(initializer_list_t init = {}) { return basic_json(init, false, value_t::object); } @@ -1759,14 +8661,18 @@ class basic_json @brief construct an array with count copies of given value Constructs a JSON array value by creating @a cnt copies of a passed value. - In case @a cnt is `0`, an empty array is created. As postcondition, - `std::distance(begin(),end()) == cnt` holds. + In case @a cnt is `0`, an empty array is created. @param[in] cnt the number of JSON copies of @a val to create @param[in] val the JSON value to copy + @post `std::distance(begin(),end()) == cnt` holds. + @complexity Linear in @a cnt. + @exceptionsafety Strong guarantee: if an exception is thrown, there are no + changes to any JSON value. + @liveexample{The following code shows examples for the @ref basic_json(size_type\, const basic_json&) constructor.,basic_json__size_type_basic_json} @@ -1777,6 +8683,7 @@ class basic_json : m_type(value_t::array) { m_value.array = create<array_t>(cnt, val); + assert_invariant(); } /*! @@ -1784,12 +8691,13 @@ class basic_json Constructs the JSON value with the contents of the range `[first, last)`. The semantics depends on the different types a JSON value can have: - - In case of primitive types (number, boolean, or string), @a first must - be `begin()` and @a last must be `end()`. In this case, the value is - copied. Otherwise, std::out_of_range is thrown. + - In case of a null type, invalid_iterator.206 is thrown. + - In case of other primitive types (number, boolean, or string), @a first + must be `begin()` and @a last must be `end()`. In this case, the value is + copied. Otherwise, invalid_iterator.204 is thrown. - In case of structured types (array, object), the constructor behaves as - similar versions for `std::vector`. - - In case of a null type, std::domain_error is thrown. + similar versions for `std::vector` or `std::map`; that is, a JSON array + or object is constructed from the values in the range. @tparam InputIT an input iterator type (@ref iterator or @ref const_iterator) @@ -1797,36 +8705,59 @@ class basic_json @param[in] first begin of the range to copy from (included) @param[in] last end of the range to copy from (excluded) - @throw std::domain_error if iterators are not compatible; that is, do not - belong to the same JSON value; example: `"iterators are not compatible"` - @throw std::out_of_range if iterators are for a primitive type (number, - boolean, or string) where an out of range error can be detected easily; - example: `"iterators out of range"` - @throw std::bad_alloc if allocation for object, array, or string fails - @throw std::domain_error if called with a null value; example: `"cannot - use construct with iterators from null"` + @pre Iterators @a first and @a last must be initialized. **This + precondition is enforced with an assertion (see warning).** If + assertions are switched off, a violation of this precondition yields + undefined behavior. + + @pre Range `[first, last)` is valid. Usually, this precondition cannot be + checked efficiently. Only certain edge cases are detected; see the + description of the exceptions below. A violation of this precondition + yields undefined behavior. + + @warning A precondition is enforced with a runtime assertion that will + result in calling `std::abort` if this precondition is not met. + Assertions can be disabled by defining `NDEBUG` at compile time. + See http://en.cppreference.com/w/cpp/error/assert for more + information. + + @throw invalid_iterator.201 if iterators @a first and @a last are not + compatible (i.e., do not belong to the same JSON value). In this case, + the range `[first, last)` is undefined. + @throw invalid_iterator.204 if iterators @a first and @a last belong to a + primitive type (number, boolean, or string), but @a first does not point + to the first element any more. In this case, the range `[first, last)` is + undefined. See example code below. + @throw invalid_iterator.206 if iterators @a first and @a last belong to a + null value. In this case, the range `[first, last)` is undefined. @complexity Linear in distance between @a first and @a last. + @exceptionsafety Strong guarantee: if an exception is thrown, there are no + changes to any JSON value. + @liveexample{The example below shows several ways to create JSON values by specifying a subrange with iterators.,basic_json__InputIt_InputIt} @since version 1.0.0 */ - template <class InputIT, typename - std::enable_if< - std::is_same<InputIT, typename basic_json_t::iterator>::value or - std::is_same<InputIT, typename basic_json_t::const_iterator>::value - , int>::type - = 0> - basic_json(InputIT first, InputIT last) : m_type(first.m_object->m_type) + template<class InputIT, typename std::enable_if< + std::is_same<InputIT, typename basic_json_t::iterator>::value or + std::is_same<InputIT, typename basic_json_t::const_iterator>::value, int>::type = 0> + basic_json(InputIT first, InputIT last) { + assert(first.m_object != nullptr); + assert(last.m_object != nullptr); + // make sure iterator fits the current value - if (first.m_object != last.m_object) + if (JSON_UNLIKELY(first.m_object != last.m_object)) { - throw std::domain_error("iterators are not compatible"); + JSON_THROW(invalid_iterator::create(201, "iterators are not compatible")); } + // copy type from first iterator + m_type = first.m_object->m_type; + // check if iterator range is complete for primitive values switch (m_type) { @@ -1836,105 +8767,82 @@ class basic_json case value_t::number_unsigned: case value_t::string: { - if (not first.m_it.primitive_iterator.is_begin() or not last.m_it.primitive_iterator.is_end()) + if (JSON_UNLIKELY(not first.m_it.primitive_iterator.is_begin() + or not last.m_it.primitive_iterator.is_end())) { - throw std::out_of_range("iterators out of range"); + JSON_THROW(invalid_iterator::create(204, "iterators out of range")); } break; } default: - { break; - } } switch (m_type) { case value_t::number_integer: { - assert(first.m_object != nullptr); m_value.number_integer = first.m_object->m_value.number_integer; break; } case value_t::number_unsigned: { - assert(first.m_object != nullptr); m_value.number_unsigned = first.m_object->m_value.number_unsigned; break; } case value_t::number_float: { - assert(first.m_object != nullptr); m_value.number_float = first.m_object->m_value.number_float; break; } case value_t::boolean: { - assert(first.m_object != nullptr); m_value.boolean = first.m_object->m_value.boolean; break; } case value_t::string: { - assert(first.m_object != nullptr); m_value = *first.m_object->m_value.string; break; } case value_t::object: { - m_value.object = create<object_t>(first.m_it.object_iterator, last.m_it.object_iterator); + m_value.object = create<object_t>(first.m_it.object_iterator, + last.m_it.object_iterator); break; } case value_t::array: { - m_value.array = create<array_t>(first.m_it.array_iterator, last.m_it.array_iterator); + m_value.array = create<array_t>(first.m_it.array_iterator, + last.m_it.array_iterator); break; } default: - { - assert(first.m_object != nullptr); - throw std::domain_error("cannot use construct with iterators from " + first.m_object->type_name()); - } + JSON_THROW(invalid_iterator::create(206, "cannot construct with iterators from " + + std::string(first.m_object->type_name()))); } - } - - /*! - @brief construct a JSON value given an input stream - - @param[in,out] i stream to read a serialized JSON value from - @param[in] cb a parser callback function of type @ref parser_callback_t - which is used to control the deserialization by filtering unwanted values - (optional) - - @complexity Linear in the length of the input. The parser is a predictive - LL(1) parser. The complexity can be higher if the parser callback function - @a cb has a super-linear complexity. - @note A UTF-8 byte order mark is silently ignored. - - @liveexample{The example below demonstrates constructing a JSON value from - a `std::stringstream` with and without callback - function.,basic_json__istream} - - @since version 2.0.0 - */ - explicit basic_json(std::istream& i, parser_callback_t cb = nullptr) - { - *this = parser(i, cb).parse(); + assert_invariant(); } + /////////////////////////////////////// // other constructors and destructor // /////////////////////////////////////// + /// @private + basic_json(const detail::json_ref<basic_json>& ref) + : basic_json(ref.moved_or_copied()) + {} + /*! @brief copy constructor @@ -1942,16 +8850,19 @@ class basic_json @param[in] other the JSON value to copy + @post `*this == other` + @complexity Linear in the size of @a other. + @exceptionsafety Strong guarantee: if an exception is thrown, there are no + changes to any JSON value. + @requirement This function helps `basic_json` satisfying the [Container](http://en.cppreference.com/w/cpp/concept/Container) requirements: - The complexity is linear. - As postcondition, it holds: `other == basic_json(other)`. - @throw std::bad_alloc if allocation for object, array, or string fails. - @liveexample{The following code shows an example for the copy constructor.,basic_json__basic_json} @@ -1960,25 +8871,25 @@ class basic_json basic_json(const basic_json& other) : m_type(other.m_type) { + // check of passed value is valid + other.assert_invariant(); + switch (m_type) { case value_t::object: { - assert(other.m_value.object != nullptr); m_value = *other.m_value.object; break; } case value_t::array: { - assert(other.m_value.array != nullptr); m_value = *other.m_value.array; break; } case value_t::string: { - assert(other.m_value.string != nullptr); m_value = *other.m_value.string; break; } @@ -2008,10 +8919,10 @@ class basic_json } default: - { break; - } } + + assert_invariant(); } /*! @@ -2023,10 +8934,18 @@ class basic_json @param[in,out] other value to move to this object - @post @a other is a JSON null value + @post `*this` has the same value as @a other before the call. + @post @a other is a JSON null value. @complexity Constant. + @exceptionsafety No-throw guarantee: this constructor never throws + exceptions. + + @requirement This function helps `basic_json` satisfying the + [MoveConstructible](http://en.cppreference.com/w/cpp/concept/MoveConstructible) + requirements. + @liveexample{The code below shows the move constructor explicitly called via std::move.,basic_json__moveconstructor} @@ -2036,9 +8955,14 @@ class basic_json : m_type(std::move(other.m_type)), m_value(std::move(other.m_value)) { + // check that passed value is valid + other.assert_invariant(); + // invalidate payload other.m_type = value_t::null; other.m_value = {}; + + assert_invariant(); } /*! @@ -2046,7 +8970,7 @@ class basic_json Copy assignment operator. Copies a JSON value via the "copy and swap" strategy: It is expressed in terms of the copy constructor, destructor, - and the swap() member function. + and the `swap()` member function. @param[in] other value to copy from @@ -2071,9 +8995,14 @@ class basic_json std::is_nothrow_move_assignable<json_value>::value ) { + // check that passed value is valid + other.assert_invariant(); + using std::swap; swap(m_type, other.m_type); swap(m_value, other.m_value); + + assert_invariant(); return *this; } @@ -2094,38 +9023,8 @@ class basic_json */ ~basic_json() { - switch (m_type) - { - case value_t::object: - { - AllocatorType<object_t> alloc; - alloc.destroy(m_value.object); - alloc.deallocate(m_value.object, 1); - break; - } - - case value_t::array: - { - AllocatorType<array_t> alloc; - alloc.destroy(m_value.array); - alloc.deallocate(m_value.array, 1); - break; - } - - case value_t::string: - { - AllocatorType<string_t> alloc; - alloc.destroy(m_value.string); - alloc.deallocate(m_value.string, 1); - break; - } - - default: - { - // all other types need no specific destructor - break; - } - } + assert_invariant(); + m_value.destroy(m_type); } /// @} @@ -2136,45 +9035,61 @@ class basic_json /////////////////////// /// @name object inspection + /// Functions to inspect the type of a JSON value. /// @{ /*! @brief serialization Serialization function for JSON values. The function tries to mimic - Python's @p json.dumps() function, and currently supports its @p indent - parameter. + Python's `json.dumps()` function, and currently supports its @a indent + and @a ensure_ascii parameters. - @param[in] indent if indent is nonnegative, then array elements and object + @param[in] indent If indent is nonnegative, then array elements and object members will be pretty-printed with that indent level. An indent level of - 0 will only insert newlines. -1 (the default) selects the most compact - representation + `0` will only insert newlines. `-1` (the default) selects the most compact + representation. + @param[in] indent_char The character to use for indentation if @a indent is + greater than `0`. The default is ` ` (space). + @param[in] ensure_ascii If @a ensure_ascii is true, all non-ASCII characters + in the output are escaped with `\uXXXX` sequences, and the result consists + of ASCII characters only. @return string containing the serialization of the JSON value + @throw type_error.316 if a string stored inside the JSON value is not + UTF-8 encoded + @complexity Linear. - @liveexample{The following example shows the effect of different @a indent - parameters to the result of the serialization.,dump} + @exceptionsafety Strong guarantee: if an exception is thrown, there are no + changes in the JSON value. + + @liveexample{The following example shows the effect of different @a indent\, + @a indent_char\, and @a ensure_ascii parameters to the result of the + serialization.,dump} @see https://docs.python.org/2/library/json.html#json.dump - @since version 1.0.0 + @since version 1.0.0; indentation character @a indent_char, option + @a ensure_ascii and exceptions added in version 3.0.0 */ - string_t dump(const int indent = -1) const + string_t dump(const int indent = -1, const char indent_char = ' ', + const bool ensure_ascii = false) const { - std::stringstream ss; + string_t result; + serializer s(detail::output_adapter<char>(result), indent_char); if (indent >= 0) { - dump(ss, true, static_cast<unsigned int>(indent)); + s.dump(*this, true, ensure_ascii, static_cast<unsigned int>(indent)); } else { - dump(ss, false, 0); + s.dump(*this, false, ensure_ascii, 0); } - return ss.str(); + return result; } /*! @@ -2184,6 +9099,17 @@ class basic_json enumeration. @return the type of the JSON value + Value type | return value + ------------------------- | ------------------------- + null | value_t::null + boolean | value_t::boolean + string | value_t::string + number (integer) | value_t::number_integer + number (unsigned integer) | value_t::number_unsigned + number (floating-point) | value_t::number_float + object | value_t::object + array | value_t::array + discarded | value_t::discarded @complexity Constant. @@ -2193,6 +9119,9 @@ class basic_json @liveexample{The following code exemplifies `type()` for all JSON types.,type} + @sa @ref operator value_t() -- return the type of the JSON value (implicit) + @sa @ref type_name() -- return the type as string + @since version 1.0.0 */ constexpr value_t type() const noexcept @@ -2203,8 +9132,8 @@ class basic_json /*! @brief return whether type is primitive - This function returns true iff the JSON type is primitive (string, number, - boolean, or null). + This function returns true if and only if the JSON type is primitive + (string, number, boolean, or null). @return `true` if type is primitive (string, number, boolean, or null), `false` otherwise. @@ -2233,8 +9162,8 @@ class basic_json /*! @brief return whether type is structured - This function returns true iff the JSON type is structured (array or - object). + This function returns true if and only if the JSON type is structured + (array or object). @return `true` if type is structured (array or object), `false` otherwise. @@ -2260,7 +9189,7 @@ class basic_json /*! @brief return whether value is null - This function returns true iff the JSON value is null. + This function returns true if and only if the JSON value is null. @return `true` if type is null, `false` otherwise. @@ -2276,13 +9205,13 @@ class basic_json */ constexpr bool is_null() const noexcept { - return m_type == value_t::null; + return (m_type == value_t::null); } /*! @brief return whether value is a boolean - This function returns true iff the JSON value is a boolean. + This function returns true if and only if the JSON value is a boolean. @return `true` if type is boolean, `false` otherwise. @@ -2298,14 +9227,14 @@ class basic_json */ constexpr bool is_boolean() const noexcept { - return m_type == value_t::boolean; + return (m_type == value_t::boolean); } /*! @brief return whether value is a number - This function returns true iff the JSON value is a number. This includes - both integer and floating-point values. + This function returns true if and only if the JSON value is a number. This + includes both integer (signed and unsigned) and floating-point values. @return `true` if type is number (regardless whether integer, unsigned integer or floating-type), `false` otherwise. @@ -2334,8 +9263,8 @@ class basic_json /*! @brief return whether value is an integer number - This function returns true iff the JSON value is an integer or unsigned - integer number. This excludes floating-point values. + This function returns true if and only if the JSON value is a signed or + unsigned integer number. This excludes floating-point values. @return `true` if type is an integer or unsigned integer number, `false` otherwise. @@ -2357,14 +9286,14 @@ class basic_json */ constexpr bool is_number_integer() const noexcept { - return m_type == value_t::number_integer or m_type == value_t::number_unsigned; + return (m_type == value_t::number_integer or m_type == value_t::number_unsigned); } /*! @brief return whether value is an unsigned integer number - This function returns true iff the JSON value is an unsigned integer - number. This excludes floating-point and (signed) integer values. + This function returns true if and only if the JSON value is an unsigned + integer number. This excludes floating-point and signed integer values. @return `true` if type is an unsigned integer number, `false` otherwise. @@ -2385,14 +9314,14 @@ class basic_json */ constexpr bool is_number_unsigned() const noexcept { - return m_type == value_t::number_unsigned; + return (m_type == value_t::number_unsigned); } /*! @brief return whether value is a floating-point number - This function returns true iff the JSON value is a floating-point number. - This excludes integer and unsigned integer values. + This function returns true if and only if the JSON value is a + floating-point number. This excludes signed and unsigned integer values. @return `true` if type is a floating-point number, `false` otherwise. @@ -2413,13 +9342,13 @@ class basic_json */ constexpr bool is_number_float() const noexcept { - return m_type == value_t::number_float; + return (m_type == value_t::number_float); } /*! @brief return whether value is an object - This function returns true iff the JSON value is an object. + This function returns true if and only if the JSON value is an object. @return `true` if type is object, `false` otherwise. @@ -2435,13 +9364,13 @@ class basic_json */ constexpr bool is_object() const noexcept { - return m_type == value_t::object; + return (m_type == value_t::object); } /*! @brief return whether value is an array - This function returns true iff the JSON value is an array. + This function returns true if and only if the JSON value is an array. @return `true` if type is array, `false` otherwise. @@ -2457,13 +9386,13 @@ class basic_json */ constexpr bool is_array() const noexcept { - return m_type == value_t::array; + return (m_type == value_t::array); } /*! @brief return whether value is a string - This function returns true iff the JSON value is a string. + This function returns true if and only if the JSON value is a string. @return `true` if type is string, `false` otherwise. @@ -2479,14 +9408,14 @@ class basic_json */ constexpr bool is_string() const noexcept { - return m_type == value_t::string; + return (m_type == value_t::string); } /*! @brief return whether value is discarded - This function returns true iff the JSON value was discarded during parsing - with a callback function (see @ref parser_callback_t). + This function returns true if and only if the JSON value was discarded + during parsing with a callback function (see @ref parser_callback_t). @note This function will always be `false` for JSON values after parsing. That is, discarded values can only occur during parsing, but will be @@ -2506,7 +9435,7 @@ class basic_json */ constexpr bool is_discarded() const noexcept { - return m_type == value_t::discarded; + return (m_type == value_t::discarded); } /*! @@ -2525,6 +9454,9 @@ class basic_json @liveexample{The following code exemplifies the @ref value_t operator for all JSON types.,operator__value_t} + @sa @ref type() -- return the type of the JSON value (explicit) + @sa @ref type_name() -- return the type as string + @since version 1.0.0 */ constexpr operator value_t() const noexcept @@ -2539,263 +9471,97 @@ class basic_json // value access // ////////////////// - /// get an object (explicit) - template <class T, typename - std::enable_if< - std::is_convertible<typename object_t::key_type, typename T::key_type>::value and - std::is_convertible<basic_json_t, typename T::mapped_type>::value - , int>::type = 0> - T get_impl(T*) const - { - if (is_object()) - { - assert(m_value.object != nullptr); - return T(m_value.object->begin(), m_value.object->end()); - } - else - { - throw std::domain_error("type must be object, but is " + type_name()); - } - } - - /// get an object (explicit) - object_t get_impl(object_t*) const - { - if (is_object()) - { - assert(m_value.object != nullptr); - return *(m_value.object); - } - else - { - throw std::domain_error("type must be object, but is " + type_name()); - } - } - - /// get an array (explicit) - template <class T, typename - std::enable_if< - std::is_convertible<basic_json_t, typename T::value_type>::value and - not std::is_same<basic_json_t, typename T::value_type>::value and - not std::is_arithmetic<T>::value and - not std::is_convertible<std::string, T>::value and - not has_mapped_type<T>::value - , int>::type = 0> - T get_impl(T*) const - { - if (is_array()) - { - T to_vector; - assert(m_value.array != nullptr); - std::transform(m_value.array->begin(), m_value.array->end(), - std::inserter(to_vector, to_vector.end()), [](basic_json i) - { - return i.get<typename T::value_type>(); - }); - return to_vector; - } - else - { - throw std::domain_error("type must be array, but is " + type_name()); - } - } - - /// get an array (explicit) - template <class T, typename - std::enable_if< - std::is_convertible<basic_json_t, T>::value and - not std::is_same<basic_json_t, T>::value - , int>::type = 0> - std::vector<T> get_impl(std::vector<T>*) const - { - if (is_array()) - { - std::vector<T> to_vector; - assert(m_value.array != nullptr); - to_vector.reserve(m_value.array->size()); - std::transform(m_value.array->begin(), m_value.array->end(), - std::inserter(to_vector, to_vector.end()), [](basic_json i) - { - return i.get<T>(); - }); - return to_vector; - } - else - { - throw std::domain_error("type must be array, but is " + type_name()); - } - } - - /// get an array (explicit) - template <class T, typename - std::enable_if< - std::is_same<basic_json, typename T::value_type>::value and - not has_mapped_type<T>::value - , int>::type = 0> - T get_impl(T*) const - { - if (is_array()) - { - assert(m_value.array != nullptr); - return T(m_value.array->begin(), m_value.array->end()); - } - else - { - throw std::domain_error("type must be array, but is " + type_name()); - } - } - - /// get an array (explicit) - array_t get_impl(array_t*) const - { - if (is_array()) - { - assert(m_value.array != nullptr); - return *(m_value.array); - } - else - { - throw std::domain_error("type must be array, but is " + type_name()); - } - } - - /// get a string (explicit) - template <typename T, typename - std::enable_if< - std::is_convertible<string_t, T>::value - , int>::type = 0> - T get_impl(T*) const - { - if (is_string()) - { - assert(m_value.string != nullptr); - return *m_value.string; - } - else - { - throw std::domain_error("type must be string, but is " + type_name()); - } - } - - /// get a number (explicit) - template<typename T, typename - std::enable_if< - std::is_arithmetic<T>::value - , int>::type = 0> - T get_impl(T*) const + /// get a boolean (explicit) + boolean_t get_impl(boolean_t* /*unused*/) const { - switch (m_type) + if (JSON_LIKELY(is_boolean())) { - case value_t::number_integer: - { - return static_cast<T>(m_value.number_integer); - } - - case value_t::number_unsigned: - { - return static_cast<T>(m_value.number_unsigned); - } - - case value_t::number_float: - { - return static_cast<T>(m_value.number_float); - } - - default: - { - throw std::domain_error("type must be number, but is " + type_name()); - } + return m_value.boolean; } - } - /// get a boolean (explicit) - constexpr boolean_t get_impl(boolean_t*) const - { - return is_boolean() - ? m_value.boolean - : throw std::domain_error("type must be boolean, but is " + type_name()); + JSON_THROW(type_error::create(302, "type must be boolean, but is " + std::string(type_name()))); } /// get a pointer to the value (object) - object_t* get_impl_ptr(object_t*) noexcept + object_t* get_impl_ptr(object_t* /*unused*/) noexcept { return is_object() ? m_value.object : nullptr; } /// get a pointer to the value (object) - constexpr const object_t* get_impl_ptr(const object_t*) const noexcept + constexpr const object_t* get_impl_ptr(const object_t* /*unused*/) const noexcept { return is_object() ? m_value.object : nullptr; } /// get a pointer to the value (array) - array_t* get_impl_ptr(array_t*) noexcept + array_t* get_impl_ptr(array_t* /*unused*/) noexcept { return is_array() ? m_value.array : nullptr; } /// get a pointer to the value (array) - constexpr const array_t* get_impl_ptr(const array_t*) const noexcept + constexpr const array_t* get_impl_ptr(const array_t* /*unused*/) const noexcept { return is_array() ? m_value.array : nullptr; } /// get a pointer to the value (string) - string_t* get_impl_ptr(string_t*) noexcept + string_t* get_impl_ptr(string_t* /*unused*/) noexcept { return is_string() ? m_value.string : nullptr; } /// get a pointer to the value (string) - constexpr const string_t* get_impl_ptr(const string_t*) const noexcept + constexpr const string_t* get_impl_ptr(const string_t* /*unused*/) const noexcept { return is_string() ? m_value.string : nullptr; } /// get a pointer to the value (boolean) - boolean_t* get_impl_ptr(boolean_t*) noexcept + boolean_t* get_impl_ptr(boolean_t* /*unused*/) noexcept { return is_boolean() ? &m_value.boolean : nullptr; } /// get a pointer to the value (boolean) - constexpr const boolean_t* get_impl_ptr(const boolean_t*) const noexcept + constexpr const boolean_t* get_impl_ptr(const boolean_t* /*unused*/) const noexcept { return is_boolean() ? &m_value.boolean : nullptr; } /// get a pointer to the value (integer number) - number_integer_t* get_impl_ptr(number_integer_t*) noexcept + number_integer_t* get_impl_ptr(number_integer_t* /*unused*/) noexcept { return is_number_integer() ? &m_value.number_integer : nullptr; } /// get a pointer to the value (integer number) - constexpr const number_integer_t* get_impl_ptr(const number_integer_t*) const noexcept + constexpr const number_integer_t* get_impl_ptr(const number_integer_t* /*unused*/) const noexcept { return is_number_integer() ? &m_value.number_integer : nullptr; } /// get a pointer to the value (unsigned number) - number_unsigned_t* get_impl_ptr(number_unsigned_t*) noexcept + number_unsigned_t* get_impl_ptr(number_unsigned_t* /*unused*/) noexcept { return is_number_unsigned() ? &m_value.number_unsigned : nullptr; } /// get a pointer to the value (unsigned number) - constexpr const number_unsigned_t* get_impl_ptr(const number_unsigned_t*) const noexcept + constexpr const number_unsigned_t* get_impl_ptr(const number_unsigned_t* /*unused*/) const noexcept { return is_number_unsigned() ? &m_value.number_unsigned : nullptr; } /// get a pointer to the value (floating-point number) - number_float_t* get_impl_ptr(number_float_t*) noexcept + number_float_t* get_impl_ptr(number_float_t* /*unused*/) noexcept { return is_number_float() ? &m_value.number_float : nullptr; } /// get a pointer to the value (floating-point number) - constexpr const number_float_t* get_impl_ptr(const number_float_t*) const noexcept + constexpr const number_float_t* get_impl_ptr(const number_float_t* /*unused*/) const noexcept { return is_number_float() ? &m_value.number_float : nullptr; } @@ -2803,52 +9569,84 @@ class basic_json /*! @brief helper function to implement get_ref() - This funcion helps to implement get_ref() without code duplication for + This function helps to implement get_ref() without code duplication for const and non-const overloads @tparam ThisType will be deduced as `basic_json` or `const basic_json` - @throw std::domain_error if ReferenceType does not match underlying value + @throw type_error.303 if ReferenceType does not match underlying value type of the current JSON */ template<typename ReferenceType, typename ThisType> static ReferenceType get_ref_impl(ThisType& obj) { // delegate the call to get_ptr<>() - using PointerType = typename std::add_pointer<ReferenceType>::type; - auto ptr = obj.template get_ptr<PointerType>(); + auto ptr = obj.template get_ptr<typename std::add_pointer<ReferenceType>::type>(); - if (ptr != nullptr) + if (JSON_LIKELY(ptr != nullptr)) { return *ptr; } - else - { - throw std::domain_error("incompatible ReferenceType for get_ref, actual type is " + - obj.type_name()); - } + + JSON_THROW(type_error::create(303, "incompatible ReferenceType for get_ref, actual type is " + std::string(obj.type_name()))); } public: - /// @name value access + /// Direct access to the stored value of a JSON value. /// @{ /*! + @brief get special-case overload + + This overloads avoids a lot of template boilerplate, it can be seen as the + identity method + + @tparam BasicJsonType == @ref basic_json + + @return a copy of *this + + @complexity Constant. + + @since version 2.1.0 + */ + template<typename BasicJsonType, detail::enable_if_t< + std::is_same<typename std::remove_const<BasicJsonType>::type, basic_json_t>::value, + int> = 0> + basic_json get() const + { + return *this; + } + + /*! @brief get a value (explicit) - Explicit type conversion between the JSON value and a compatible value. + Explicit type conversion between the JSON value and a compatible value + which is [CopyConstructible](http://en.cppreference.com/w/cpp/concept/CopyConstructible) + and [DefaultConstructible](http://en.cppreference.com/w/cpp/concept/DefaultConstructible). + The value is converted by calling the @ref json_serializer<ValueType> + `from_json()` method. - @tparam ValueType non-pointer type compatible to the JSON value, for - instance `int` for JSON integer numbers, `bool` for JSON booleans, or - `std::vector` types for JSON arrays + The function is equivalent to executing + @code {.cpp} + ValueType ret; + JSONSerializer<ValueType>::from_json(*this, ret); + return ret; + @endcode - @return copy of the JSON value, converted to type @a ValueType + This overloads is chosen if: + - @a ValueType is not @ref basic_json, + - @ref json_serializer<ValueType> has a `from_json()` method of the form + `void from_json(const basic_json&, ValueType&)`, and + - @ref json_serializer<ValueType> does not have a `from_json()` method of + the form `ValueType from_json(const basic_json&)` - @throw std::domain_error in case passed type @a ValueType is incompatible - to JSON; example: `"type must be object, but is null"` + @tparam ValueTypeCV the provided value type + @tparam ValueType the returned value type - @complexity Linear in the size of the JSON value. + @return copy of the JSON value, converted to @a ValueType + + @throw what @ref json_serializer<ValueType> `from_json()` method throws @liveexample{The example below shows several conversions from JSON values to other types. There a few things to note: (1) Floating-point numbers can @@ -2857,23 +9655,71 @@ class basic_json associative containers such as `std::unordered_map<std::string\, json>`.,get__ValueType_const} - @internal - The idea of using a casted null pointer to choose the correct - implementation is from <http://stackoverflow.com/a/8315197/266378>. - @endinternal + @since version 2.1.0 + */ + template<typename ValueTypeCV, typename ValueType = detail::uncvref_t<ValueTypeCV>, + detail::enable_if_t < + not std::is_same<basic_json_t, ValueType>::value and + detail::has_from_json<basic_json_t, ValueType>::value and + not detail::has_non_default_from_json<basic_json_t, ValueType>::value, + int> = 0> + ValueType get() const noexcept(noexcept( + JSONSerializer<ValueType>::from_json(std::declval<const basic_json_t&>(), std::declval<ValueType&>()))) + { + // we cannot static_assert on ValueTypeCV being non-const, because + // there is support for get<const basic_json_t>(), which is why we + // still need the uncvref + static_assert(not std::is_reference<ValueTypeCV>::value, + "get() cannot be used with reference types, you might want to use get_ref()"); + static_assert(std::is_default_constructible<ValueType>::value, + "types must be DefaultConstructible when used with get()"); - @sa @ref operator ValueType() const for implicit conversion - @sa @ref get() for pointer-member access + ValueType ret; + JSONSerializer<ValueType>::from_json(*this, ret); + return ret; + } - @since version 1.0.0 + /*! + @brief get a value (explicit); special case + + Explicit type conversion between the JSON value and a compatible value + which is **not** [CopyConstructible](http://en.cppreference.com/w/cpp/concept/CopyConstructible) + and **not** [DefaultConstructible](http://en.cppreference.com/w/cpp/concept/DefaultConstructible). + The value is converted by calling the @ref json_serializer<ValueType> + `from_json()` method. + + The function is equivalent to executing + @code {.cpp} + return JSONSerializer<ValueTypeCV>::from_json(*this); + @endcode + + This overloads is chosen if: + - @a ValueType is not @ref basic_json and + - @ref json_serializer<ValueType> has a `from_json()` method of the form + `ValueType from_json(const basic_json&)` + + @note If @ref json_serializer<ValueType> has both overloads of + `from_json()`, this one is chosen. + + @tparam ValueTypeCV the provided value type + @tparam ValueType the returned value type + + @return copy of the JSON value, converted to @a ValueType + + @throw what @ref json_serializer<ValueType> `from_json()` method throws + + @since version 2.1.0 */ - template<typename ValueType, typename - std::enable_if< - not std::is_pointer<ValueType>::value - , int>::type = 0> - ValueType get() const + template<typename ValueTypeCV, typename ValueType = detail::uncvref_t<ValueTypeCV>, + detail::enable_if_t<not std::is_same<basic_json_t, ValueType>::value and + detail::has_non_default_from_json<basic_json_t, ValueType>::value, + int> = 0> + ValueType get() const noexcept(noexcept( + JSONSerializer<ValueTypeCV>::from_json(std::declval<const basic_json_t&>()))) { - return get_impl(static_cast<ValueType*>(nullptr)); + static_assert(not std::is_reference<ValueTypeCV>::value, + "get() cannot be used with reference types, you might want to use get_ref()"); + return JSONSerializer<ValueTypeCV>::from_json(*this); } /*! @@ -2882,7 +9728,8 @@ class basic_json Explicit pointer access to the internally stored JSON value. No copies are made. - @warning The pointer becomes invalid if the underlying JSON object changes. + @warning The pointer becomes invalid if the underlying JSON object + changes. @tparam PointerType pointer type; must be a pointer to @ref array_t, @ref object_t, @ref string_t, @ref boolean_t, @ref number_integer_t, @@ -2902,10 +9749,8 @@ class basic_json @since version 1.0.0 */ - template<typename PointerType, typename - std::enable_if< - std::is_pointer<PointerType>::value - , int>::type = 0> + template<typename PointerType, typename std::enable_if< + std::is_pointer<PointerType>::value, int>::type = 0> PointerType get() noexcept { // delegate the call to get_ptr @@ -2916,10 +9761,8 @@ class basic_json @brief get a pointer value (explicit) @copydoc get() */ - template<typename PointerType, typename - std::enable_if< - std::is_pointer<PointerType>::value - , int>::type = 0> + template<typename PointerType, typename std::enable_if< + std::is_pointer<PointerType>::value, int>::type = 0> constexpr const PointerType get() const noexcept { // delegate the call to get_ptr @@ -2937,7 +9780,8 @@ class basic_json @tparam PointerType pointer type; must be a pointer to @ref array_t, @ref object_t, @ref string_t, @ref boolean_t, @ref number_integer_t, - @ref number_unsigned_t, or @ref number_float_t. + @ref number_unsigned_t, or @ref number_float_t. Enforced by a static + assertion. @return pointer to the internally stored JSON value if the requested pointer type @a PointerType fits to the JSON value; `nullptr` otherwise @@ -2951,12 +9795,25 @@ class basic_json @since version 1.0.0 */ - template<typename PointerType, typename - std::enable_if< - std::is_pointer<PointerType>::value - , int>::type = 0> + template<typename PointerType, typename std::enable_if< + std::is_pointer<PointerType>::value, int>::type = 0> PointerType get_ptr() noexcept { + // get the type of the PointerType (remove pointer and const) + using pointee_t = typename std::remove_const<typename + std::remove_pointer<typename + std::remove_const<PointerType>::type>::type>::type; + // make sure the type matches the allowed types + static_assert( + std::is_same<object_t, pointee_t>::value + or std::is_same<array_t, pointee_t>::value + or std::is_same<string_t, pointee_t>::value + or std::is_same<boolean_t, pointee_t>::value + or std::is_same<number_integer_t, pointee_t>::value + or std::is_same<number_unsigned_t, pointee_t>::value + or std::is_same<number_float_t, pointee_t>::value + , "incompatible pointer type"); + // delegate the call to get_impl_ptr<>() return get_impl_ptr(static_cast<PointerType>(nullptr)); } @@ -2965,21 +9822,34 @@ class basic_json @brief get a pointer value (implicit) @copydoc get_ptr() */ - template<typename PointerType, typename - std::enable_if< - std::is_pointer<PointerType>::value - and std::is_const<typename std::remove_pointer<PointerType>::type>::value - , int>::type = 0> + template<typename PointerType, typename std::enable_if< + std::is_pointer<PointerType>::value and + std::is_const<typename std::remove_pointer<PointerType>::type>::value, int>::type = 0> constexpr const PointerType get_ptr() const noexcept { + // get the type of the PointerType (remove pointer and const) + using pointee_t = typename std::remove_const<typename + std::remove_pointer<typename + std::remove_const<PointerType>::type>::type>::type; + // make sure the type matches the allowed types + static_assert( + std::is_same<object_t, pointee_t>::value + or std::is_same<array_t, pointee_t>::value + or std::is_same<string_t, pointee_t>::value + or std::is_same<boolean_t, pointee_t>::value + or std::is_same<number_integer_t, pointee_t>::value + or std::is_same<number_unsigned_t, pointee_t>::value + or std::is_same<number_float_t, pointee_t>::value + , "incompatible pointer type"); + // delegate the call to get_impl_ptr<>() const - return get_impl_ptr(static_cast<const PointerType>(nullptr)); + return get_impl_ptr(static_cast<PointerType>(nullptr)); } /*! @brief get a reference value (implicit) - Implict reference access to the internally stored JSON value. No copies + Implicit reference access to the internally stored JSON value. No copies are made. @warning Writing data to the referee of the result yields an undefined @@ -2987,14 +9857,14 @@ class basic_json @tparam ReferenceType reference type; must be a reference to @ref array_t, @ref object_t, @ref string_t, @ref boolean_t, @ref number_integer_t, or - @ref number_float_t. + @ref number_float_t. Enforced by static assertion. @return reference to the internally stored JSON value if the requested reference type @a ReferenceType fits to the JSON value; throws - std::domain_error otherwise + type_error.303 otherwise - @throw std::domain_error in case passed type @a ReferenceType is - incompatible with the stored JSON value + @throw type_error.303 in case passed type @a ReferenceType is incompatible + with the stored JSON value; see example below @complexity Constant. @@ -3002,10 +9872,8 @@ class basic_json @since version 1.1.0 */ - template<typename ReferenceType, typename - std::enable_if< - std::is_reference<ReferenceType>::value - , int>::type = 0> + template<typename ReferenceType, typename std::enable_if< + std::is_reference<ReferenceType>::value, int>::type = 0> ReferenceType get_ref() { // delegate call to get_ref_impl @@ -3016,11 +9884,9 @@ class basic_json @brief get a reference value (implicit) @copydoc get_ref() */ - template<typename ReferenceType, typename - std::enable_if< - std::is_reference<ReferenceType>::value - and std::is_const<typename std::remove_reference<ReferenceType>::type>::value - , int>::type = 0> + template<typename ReferenceType, typename std::enable_if< + std::is_reference<ReferenceType>::value and + std::is_const<typename std::remove_reference<ReferenceType>::type>::value, int>::type = 0> ReferenceType get_ref() const { // delegate call to get_ref_impl @@ -3041,8 +9907,9 @@ class basic_json @return copy of the JSON value, converted to type @a ValueType - @throw std::domain_error in case passed type @a ValueType is incompatible - to JSON, thrown by @ref get() const + @throw type_error.302 in case passed type @a ValueType is incompatible + to the JSON value type (e.g., the JSON value is of type boolean, but a + string is requested); see example below @complexity Linear in the size of the JSON value. @@ -3055,13 +9922,16 @@ class basic_json @since version 1.0.0 */ - template < typename ValueType, typename - std::enable_if < - not std::is_pointer<ValueType>::value - and not std::is_same<ValueType, typename string_t::value_type>::value -#ifndef _MSC_VER // Fix for issue #167 operator<< abiguity under VS2015 + template < typename ValueType, typename std::enable_if < + not std::is_pointer<ValueType>::value and + not std::is_same<ValueType, detail::json_ref<basic_json>>::value and + not std::is_same<ValueType, typename string_t::value_type>::value +#ifndef _MSC_VER // fix for issue #167 operator<< ambiguity under VS2015 and not std::is_same<ValueType, std::initializer_list<typename string_t::value_type>>::value #endif +#if defined(JSON_HAS_CPP_17) + and not std::is_same<ValueType, typename std::string_view>::value +#endif , int >::type = 0 > operator ValueType() const { @@ -3077,6 +9947,7 @@ class basic_json //////////////////// /// @name element access + /// Access to the JSON value. /// @{ /*! @@ -3089,37 +9960,40 @@ class basic_json @return reference to the element at index @a idx - @throw std::domain_error if the JSON value is not an array; example: - `"cannot use at() with string"` - @throw std::out_of_range if the index @a idx is out of range of the array; - that is, `idx >= size()`; example: `"array index 7 is out of range"` + @throw type_error.304 if the JSON value is not an array; in this case, + calling `at` with an index makes no sense. See example below. + @throw out_of_range.401 if the index @a idx is out of range of the array; + that is, `idx >= size()`. See example below. - @complexity Constant. + @exceptionsafety Strong guarantee: if an exception is thrown, there are no + changes in the JSON value. - @liveexample{The example below shows how array elements can be read and - written using `at()`.,at__size_type} + @complexity Constant. @since version 1.0.0 + + @liveexample{The example below shows how array elements can be read and + written using `at()`. It also demonstrates the different exceptions that + can be thrown.,at__size_type} */ reference at(size_type idx) { // at only works for arrays - if (is_array()) + if (JSON_LIKELY(is_array())) { - try + JSON_TRY { - assert(m_value.array != nullptr); return m_value.array->at(idx); } - catch (std::out_of_range&) + JSON_CATCH (std::out_of_range&) { // create better exception explanation - throw std::out_of_range("array index " + std::to_string(idx) + " is out of range"); + JSON_THROW(out_of_range::create(401, "array index " + std::to_string(idx) + " is out of range")); } } else { - throw std::domain_error("cannot use at() with " + type_name()); + JSON_THROW(type_error::create(304, "cannot use at() with " + std::string(type_name()))); } } @@ -3133,37 +10007,40 @@ class basic_json @return const reference to the element at index @a idx - @throw std::domain_error if the JSON value is not an array; example: - `"cannot use at() with string"` - @throw std::out_of_range if the index @a idx is out of range of the array; - that is, `idx >= size()`; example: `"array index 7 is out of range"` + @throw type_error.304 if the JSON value is not an array; in this case, + calling `at` with an index makes no sense. See example below. + @throw out_of_range.401 if the index @a idx is out of range of the array; + that is, `idx >= size()`. See example below. - @complexity Constant. + @exceptionsafety Strong guarantee: if an exception is thrown, there are no + changes in the JSON value. - @liveexample{The example below shows how array elements can be read using - `at()`.,at__size_type_const} + @complexity Constant. @since version 1.0.0 + + @liveexample{The example below shows how array elements can be read using + `at()`. It also demonstrates the different exceptions that can be thrown., + at__size_type_const} */ const_reference at(size_type idx) const { // at only works for arrays - if (is_array()) + if (JSON_LIKELY(is_array())) { - try + JSON_TRY { - assert(m_value.array != nullptr); return m_value.array->at(idx); } - catch (std::out_of_range&) + JSON_CATCH (std::out_of_range&) { // create better exception explanation - throw std::out_of_range("array index " + std::to_string(idx) + " is out of range"); + JSON_THROW(out_of_range::create(401, "array index " + std::to_string(idx) + " is out of range")); } } else { - throw std::domain_error("cannot use at() with " + type_name()); + JSON_THROW(type_error::create(304, "cannot use at() with " + std::string(type_name()))); } } @@ -3177,41 +10054,44 @@ class basic_json @return reference to the element at key @a key - @throw std::domain_error if the JSON value is not an object; example: - `"cannot use at() with boolean"` - @throw std::out_of_range if the key @a key is is not stored in the object; - that is, `find(key) == end()`; example: `"key "the fast" not found"` + @throw type_error.304 if the JSON value is not an object; in this case, + calling `at` with a key makes no sense. See example below. + @throw out_of_range.403 if the key @a key is is not stored in the object; + that is, `find(key) == end()`. See example below. - @complexity Logarithmic in the size of the container. + @exceptionsafety Strong guarantee: if an exception is thrown, there are no + changes in the JSON value. - @liveexample{The example below shows how object elements can be read and - written using `at()`.,at__object_t_key_type} + @complexity Logarithmic in the size of the container. @sa @ref operator[](const typename object_t::key_type&) for unchecked access by reference @sa @ref value() for access by value with a default value @since version 1.0.0 + + @liveexample{The example below shows how object elements can be read and + written using `at()`. It also demonstrates the different exceptions that + can be thrown.,at__object_t_key_type} */ reference at(const typename object_t::key_type& key) { // at only works for objects - if (is_object()) + if (JSON_LIKELY(is_object())) { - try + JSON_TRY { - assert(m_value.object != nullptr); return m_value.object->at(key); } - catch (std::out_of_range&) + JSON_CATCH (std::out_of_range&) { // create better exception explanation - throw std::out_of_range("key '" + key + "' not found"); + JSON_THROW(out_of_range::create(403, "key '" + key + "' not found")); } } else { - throw std::domain_error("cannot use at() with " + type_name()); + JSON_THROW(type_error::create(304, "cannot use at() with " + std::string(type_name()))); } } @@ -3225,41 +10105,44 @@ class basic_json @return const reference to the element at key @a key - @throw std::domain_error if the JSON value is not an object; example: - `"cannot use at() with boolean"` - @throw std::out_of_range if the key @a key is is not stored in the object; - that is, `find(key) == end()`; example: `"key "the fast" not found"` + @throw type_error.304 if the JSON value is not an object; in this case, + calling `at` with a key makes no sense. See example below. + @throw out_of_range.403 if the key @a key is is not stored in the object; + that is, `find(key) == end()`. See example below. - @complexity Logarithmic in the size of the container. + @exceptionsafety Strong guarantee: if an exception is thrown, there are no + changes in the JSON value. - @liveexample{The example below shows how object elements can be read using - `at()`.,at__object_t_key_type_const} + @complexity Logarithmic in the size of the container. @sa @ref operator[](const typename object_t::key_type&) for unchecked access by reference @sa @ref value() for access by value with a default value @since version 1.0.0 + + @liveexample{The example below shows how object elements can be read using + `at()`. It also demonstrates the different exceptions that can be thrown., + at__object_t_key_type_const} */ const_reference at(const typename object_t::key_type& key) const { // at only works for objects - if (is_object()) + if (JSON_LIKELY(is_object())) { - try + JSON_TRY { - assert(m_value.object != nullptr); return m_value.object->at(key); } - catch (std::out_of_range&) + JSON_CATCH (std::out_of_range&) { // create better exception explanation - throw std::out_of_range("key '" + key + "' not found"); + JSON_THROW(out_of_range::create(403, "key '" + key + "' not found")); } } else { - throw std::domain_error("cannot use at() with " + type_name()); + JSON_THROW(type_error::create(304, "cannot use at() with " + std::string(type_name()))); } } @@ -3276,8 +10159,8 @@ class basic_json @return reference to the element at index @a idx - @throw std::domain_error if JSON is not an array or null; example: - `"cannot use operator[] with string"` + @throw type_error.305 if the JSON value is not an array or null; in that + cases, using the [] operator with an index makes no sense. @complexity Constant if @a idx is in the range of the array. Otherwise linear in `idx - size()`. @@ -3295,24 +10178,24 @@ class basic_json { m_type = value_t::array; m_value.array = create<array_t>(); + assert_invariant(); } // operator[] only works for arrays - if (is_array()) + if (JSON_LIKELY(is_array())) { - // fill up array with null values until given idx is reached - assert(m_value.array != nullptr); - for (size_t i = m_value.array->size(); i <= idx; ++i) + // fill up array with null values if given idx is outside range + if (idx >= m_value.array->size()) { - m_value.array->push_back(basic_json()); + m_value.array->insert(m_value.array->end(), + idx - m_value.array->size() + 1, + basic_json()); } return m_value.array->operator[](idx); } - else - { - throw std::domain_error("cannot use operator[] with " + type_name()); - } + + JSON_THROW(type_error::create(305, "cannot use operator[] with " + std::string(type_name()))); } /*! @@ -3324,8 +10207,8 @@ class basic_json @return const reference to the element at index @a idx - @throw std::domain_error if JSON is not an array; example: `"cannot use - operator[] with null"` + @throw type_error.305 if the JSON value is not an array; in that case, + using the [] operator with an index makes no sense. @complexity Constant. @@ -3337,15 +10220,12 @@ class basic_json const_reference operator[](size_type idx) const { // const operator[] only works for arrays - if (is_array()) + if (JSON_LIKELY(is_array())) { - assert(m_value.array != nullptr); return m_value.array->operator[](idx); } - else - { - throw std::domain_error("cannot use operator[] with " + type_name()); - } + + JSON_THROW(type_error::create(305, "cannot use operator[] with " + std::string(type_name()))); } /*! @@ -3361,8 +10241,8 @@ class basic_json @return reference to the element at key @a key - @throw std::domain_error if JSON is not an object or null; example: - `"cannot use operator[] with string"` + @throw type_error.305 if the JSON value is not an object or null; in that + cases, using the [] operator with a key makes no sense. @complexity Logarithmic in the size of the container. @@ -3382,18 +10262,16 @@ class basic_json { m_type = value_t::object; m_value.object = create<object_t>(); + assert_invariant(); } // operator[] only works for objects - if (is_object()) + if (JSON_LIKELY(is_object())) { - assert(m_value.object != nullptr); return m_value.object->operator[](key); } - else - { - throw std::domain_error("cannot use operator[] with " + type_name()); - } + + JSON_THROW(type_error::create(305, "cannot use operator[] with " + std::string(type_name()))); } /*! @@ -3409,8 +10287,11 @@ class basic_json @return const reference to the element at key @a key - @throw std::domain_error if JSON is not an object; example: `"cannot use - operator[] with null"` + @pre The element with key @a key must exist. **This precondition is + enforced with an assertion.** + + @throw type_error.305 if the JSON value is not an object; in that case, + using the [] operator with a key makes no sense. @complexity Logarithmic in the size of the container. @@ -3426,84 +10307,13 @@ class basic_json const_reference operator[](const typename object_t::key_type& key) const { // const operator[] only works for objects - if (is_object()) + if (JSON_LIKELY(is_object())) { - assert(m_value.object != nullptr); assert(m_value.object->find(key) != m_value.object->end()); return m_value.object->find(key)->second; } - else - { - throw std::domain_error("cannot use operator[] with " + type_name()); - } - } - - /*! - @brief access specified object element - - Returns a reference to the element at with specified key @a key. - - @note If @a key is not found in the object, then it is silently added to - the object and filled with a `null` value to make `key` a valid reference. - In case the value was `null` before, it is converted to an object. - - @param[in] key key of the element to access - - @return reference to the element at key @a key - - @throw std::domain_error if JSON is not an object or null; example: - `"cannot use operator[] with string"` - - @complexity Logarithmic in the size of the container. - - @liveexample{The example below shows how object elements can be read and - written using the `[]` operator.,operatorarray__key_type} - - @sa @ref at(const typename object_t::key_type&) for access by reference - with range checking - @sa @ref value() for access by value with a default value - - @since version 1.0.0 - */ - template<typename T, std::size_t n> - reference operator[](T * (&key)[n]) - { - return operator[](static_cast<const T>(key)); - } - - /*! - @brief read-only access specified object element - - Returns a const reference to the element at with specified key @a key. No - bounds checking is performed. - - @warning If the element with key @a key does not exist, the behavior is - undefined. - - @note This function is required for compatibility reasons with Clang. - - @param[in] key key of the element to access - - @return const reference to the element at key @a key - - @throw std::domain_error if JSON is not an object; example: `"cannot use - operator[] with null"` - @complexity Logarithmic in the size of the container. - - @liveexample{The example below shows how object elements can be read using - the `[]` operator.,operatorarray__key_type_const} - - @sa @ref at(const typename object_t::key_type&) for access by reference - with range checking - @sa @ref value() for access by value with a default value - - @since version 1.0.0 - */ - template<typename T, std::size_t n> - const_reference operator[](T * (&key)[n]) const - { - return operator[](static_cast<const T>(key)); + JSON_THROW(type_error::create(305, "cannot use operator[] with " + std::string(type_name()))); } /*! @@ -3519,8 +10329,8 @@ class basic_json @return reference to the element at key @a key - @throw std::domain_error if JSON is not an object or null; example: - `"cannot use operator[] with string"` + @throw type_error.305 if the JSON value is not an object or null; in that + cases, using the [] operator with a key makes no sense. @complexity Logarithmic in the size of the container. @@ -3541,18 +10351,16 @@ class basic_json { m_type = value_t::object; m_value = value_t::object; + assert_invariant(); } // at only works for objects - if (is_object()) + if (JSON_LIKELY(is_object())) { - assert(m_value.object != nullptr); return m_value.object->operator[](key); } - else - { - throw std::domain_error("cannot use operator[] with " + type_name()); - } + + JSON_THROW(type_error::create(305, "cannot use operator[] with " + std::string(type_name()))); } /*! @@ -3568,8 +10376,11 @@ class basic_json @return const reference to the element at key @a key - @throw std::domain_error if JSON is not an object; example: `"cannot use - operator[] with null"` + @pre The element with key @a key must exist. **This precondition is + enforced with an assertion.** + + @throw type_error.305 if the JSON value is not an object; in that case, + using the [] operator with a key makes no sense. @complexity Logarithmic in the size of the container. @@ -3586,29 +10397,26 @@ class basic_json const_reference operator[](T* key) const { // at only works for objects - if (is_object()) + if (JSON_LIKELY(is_object())) { - assert(m_value.object != nullptr); assert(m_value.object->find(key) != m_value.object->end()); return m_value.object->find(key)->second; } - else - { - throw std::domain_error("cannot use operator[] with " + type_name()); - } + + JSON_THROW(type_error::create(305, "cannot use operator[] with " + std::string(type_name()))); } /*! @brief access specified object element with default value - Returns either a copy of an object's element at the specified key @a key or - a given default value if no element with key @a key exists. + Returns either a copy of an object's element at the specified key @a key + or a given default value if no element with key @a key exists. The function is basically equivalent to executing @code {.cpp} try { return at(key); - } catch(std::out_of_range) { + } catch(out_of_range) { return default_value; } @endcode @@ -3631,8 +10439,8 @@ class basic_json @return copy of the element at key @a key or @a default_value if @a key is not found - @throw std::domain_error if JSON is not an object; example: `"cannot use - value() with null"` + @throw type_error.306 if the JSON value is not an object; in that case, + using `value()` with a key makes no sense. @complexity Logarithmic in the size of the container. @@ -3646,14 +10454,12 @@ class basic_json @since version 1.0.0 */ - template <class ValueType, typename - std::enable_if< - std::is_convertible<basic_json_t, ValueType>::value - , int>::type = 0> - ValueType value(const typename object_t::key_type& key, ValueType default_value) const + template<class ValueType, typename std::enable_if< + std::is_convertible<basic_json_t, ValueType>::value, int>::type = 0> + ValueType value(const typename object_t::key_type& key, const ValueType& default_value) const { // at only works for objects - if (is_object()) + if (JSON_LIKELY(is_object())) { // if key is found, return value and given default value otherwise const auto it = find(key); @@ -3661,24 +10467,91 @@ class basic_json { return *it; } - else + + return default_value; + } + + JSON_THROW(type_error::create(306, "cannot use value() with " + std::string(type_name()))); + } + + /*! + @brief overload for a default value of type const char* + @copydoc basic_json::value(const typename object_t::key_type&, ValueType) const + */ + string_t value(const typename object_t::key_type& key, const char* default_value) const + { + return value(key, string_t(default_value)); + } + + /*! + @brief access specified object element via JSON Pointer with default value + + Returns either a copy of an object's element at the specified key @a key + or a given default value if no element with key @a key exists. + + The function is basically equivalent to executing + @code {.cpp} + try { + return at(ptr); + } catch(out_of_range) { + return default_value; + } + @endcode + + @note Unlike @ref at(const json_pointer&), this function does not throw + if the given key @a key was not found. + + @param[in] ptr a JSON pointer to the element to access + @param[in] default_value the value to return if @a ptr found no value + + @tparam ValueType type compatible to JSON values, for instance `int` for + JSON integer numbers, `bool` for JSON booleans, or `std::vector` types for + JSON arrays. Note the type of the expected value at @a key and the default + value @a default_value must be compatible. + + @return copy of the element at key @a key or @a default_value if @a key + is not found + + @throw type_error.306 if the JSON value is not an objec; in that case, + using `value()` with a key makes no sense. + + @complexity Logarithmic in the size of the container. + + @liveexample{The example below shows how object elements can be queried + with a default value.,basic_json__value_ptr} + + @sa @ref operator[](const json_pointer&) for unchecked access by reference + + @since version 2.0.2 + */ + template<class ValueType, typename std::enable_if< + std::is_convertible<basic_json_t, ValueType>::value, int>::type = 0> + ValueType value(const json_pointer& ptr, const ValueType& default_value) const + { + // at only works for objects + if (JSON_LIKELY(is_object())) + { + // if pointer resolves a value, return it or use default value + JSON_TRY + { + return ptr.get_checked(this); + } + JSON_CATCH (out_of_range&) { return default_value; } } - else - { - throw std::domain_error("cannot use value() with " + type_name()); - } + + JSON_THROW(type_error::create(306, "cannot use value() with " + std::string(type_name()))); } /*! @brief overload for a default value of type const char* - @copydoc basic_json::value() + @copydoc basic_json::value(const json_pointer&, ValueType) const */ - string_t value(const typename object_t::key_type& key, const char* default_value) const + string_t value(const json_pointer& ptr, const char* default_value) const { - return value(key, string_t(default_value)); + return value(ptr, string_t(default_value)); } /*! @@ -3688,16 +10561,17 @@ class basic_json container `c`, the expression `c.front()` is equivalent to `*c.begin()`. @return In case of a structured type (array or object), a reference to the - first element is returned. In cast of number, string, or boolean values, a + first element is returned. In case of number, string, or boolean values, a reference to the value is returned. @complexity Constant. @pre The JSON value must not be `null` (would throw `std::out_of_range`) - or an empty array or object (undefined behavior, guarded by assertions). + or an empty array or object (undefined behavior, **guarded by + assertions**). @post The JSON value remains unchanged. - @throw std::out_of_range when called on `null` value + @throw invalid_iterator.214 when called on `null` value @liveexample{The following code shows an example for `front()`.,front} @@ -3730,16 +10604,18 @@ class basic_json @endcode @return In case of a structured type (array or object), a reference to the - last element is returned. In cast of number, string, or boolean values, a + last element is returned. In case of number, string, or boolean values, a reference to the value is returned. @complexity Constant. @pre The JSON value must not be `null` (would throw `std::out_of_range`) - or an empty array or object (undefined behavior, guarded by assertions). + or an empty array or object (undefined behavior, **guarded by + assertions**). @post The JSON value remains unchanged. - @throw std::out_of_range when called on `null` value. + @throw invalid_iterator.214 when called on a `null` value. See example + below. @liveexample{The following code shows an example for `back()`.,back} @@ -3778,29 +10654,30 @@ class basic_json @return Iterator following the last removed element. If the iterator @a pos refers to the last element, the `end()` iterator is returned. - @tparam InteratorType an @ref iterator or @ref const_iterator + @tparam IteratorType an @ref iterator or @ref const_iterator @post Invalidates iterators and references at or after the point of the erase, including the `end()` iterator. - @throw std::domain_error if called on a `null` value; example: `"cannot - use erase() with null"` - @throw std::domain_error if called on an iterator which does not belong to - the current JSON value; example: `"iterator does not fit current value"` - @throw std::out_of_range if called on a primitive type with invalid + @throw type_error.307 if called on a `null` value; example: `"cannot use + erase() with null"` + @throw invalid_iterator.202 if called on an iterator which does not belong + to the current JSON value; example: `"iterator does not fit current + value"` + @throw invalid_iterator.205 if called on a primitive type with invalid iterator (i.e., any iterator which is not `begin()`); example: `"iterator out of range"` @complexity The complexity depends on the type: - objects: amortized constant - - arrays: linear in distance between pos and the end of the container + - arrays: linear in distance between @a pos and the end of the container - strings: linear in the length of the string - other types: constant @liveexample{The example shows the result of `erase()` for different JSON types.,erase__IteratorType} - @sa @ref erase(InteratorType, InteratorType) -- removes the elements in + @sa @ref erase(IteratorType, IteratorType) -- removes the elements in the given range @sa @ref erase(const typename object_t::key_type&) -- removes the element from an object at the given key @@ -3809,21 +10686,19 @@ class basic_json @since version 1.0.0 */ - template <class InteratorType, typename - std::enable_if< - std::is_same<InteratorType, typename basic_json_t::iterator>::value or - std::is_same<InteratorType, typename basic_json_t::const_iterator>::value - , int>::type - = 0> - InteratorType erase(InteratorType pos) + template<class IteratorType, typename std::enable_if< + std::is_same<IteratorType, typename basic_json_t::iterator>::value or + std::is_same<IteratorType, typename basic_json_t::const_iterator>::value, int>::type + = 0> + IteratorType erase(IteratorType pos) { // make sure iterator fits the current value - if (this != pos.m_object) + if (JSON_UNLIKELY(this != pos.m_object)) { - throw std::domain_error("iterator does not fit current value"); + JSON_THROW(invalid_iterator::create(202, "iterator does not fit current value")); } - InteratorType result = end(); + IteratorType result = end(); switch (m_type) { @@ -3833,39 +10708,38 @@ class basic_json case value_t::number_unsigned: case value_t::string: { - if (not pos.m_it.primitive_iterator.is_begin()) + if (JSON_UNLIKELY(not pos.m_it.primitive_iterator.is_begin())) { - throw std::out_of_range("iterator out of range"); + JSON_THROW(invalid_iterator::create(205, "iterator out of range")); } if (is_string()) { - delete m_value.string; + AllocatorType<string_t> alloc; + std::allocator_traits<decltype(alloc)>::destroy(alloc, m_value.string); + std::allocator_traits<decltype(alloc)>::deallocate(alloc, m_value.string, 1); m_value.string = nullptr; } m_type = value_t::null; + assert_invariant(); break; } case value_t::object: { - assert(m_value.object != nullptr); result.m_it.object_iterator = m_value.object->erase(pos.m_it.object_iterator); break; } case value_t::array: { - assert(m_value.array != nullptr); result.m_it.array_iterator = m_value.array->erase(pos.m_it.array_iterator); break; } default: - { - throw std::domain_error("cannot use erase() with " + type_name()); - } + JSON_THROW(type_error::create(307, "cannot use erase() with " + std::string(type_name()))); } return result; @@ -3886,16 +10760,16 @@ class basic_json @return Iterator following the last removed element. If the iterator @a second refers to the last element, the `end()` iterator is returned. - @tparam InteratorType an @ref iterator or @ref const_iterator + @tparam IteratorType an @ref iterator or @ref const_iterator @post Invalidates iterators and references at or after the point of the erase, including the `end()` iterator. - @throw std::domain_error if called on a `null` value; example: `"cannot - use erase() with null"` - @throw std::domain_error if called on iterators which does not belong to - the current JSON value; example: `"iterators do not fit current value"` - @throw std::out_of_range if called on a primitive type with invalid + @throw type_error.307 if called on a `null` value; example: `"cannot use + erase() with null"` + @throw invalid_iterator.203 if called on iterators which does not belong + to the current JSON value; example: `"iterators do not fit current value"` + @throw invalid_iterator.204 if called on a primitive type with invalid iterators (i.e., if `first != begin()` and `last != end()`); example: `"iterators out of range"` @@ -3909,7 +10783,7 @@ class basic_json @liveexample{The example shows the result of `erase()` for different JSON types.,erase__IteratorType_IteratorType} - @sa @ref erase(InteratorType) -- removes the element at a given position + @sa @ref erase(IteratorType) -- removes the element at a given position @sa @ref erase(const typename object_t::key_type&) -- removes the element from an object at the given key @sa @ref erase(const size_type) -- removes the element from an array at @@ -3917,21 +10791,19 @@ class basic_json @since version 1.0.0 */ - template <class InteratorType, typename - std::enable_if< - std::is_same<InteratorType, typename basic_json_t::iterator>::value or - std::is_same<InteratorType, typename basic_json_t::const_iterator>::value - , int>::type - = 0> - InteratorType erase(InteratorType first, InteratorType last) + template<class IteratorType, typename std::enable_if< + std::is_same<IteratorType, typename basic_json_t::iterator>::value or + std::is_same<IteratorType, typename basic_json_t::const_iterator>::value, int>::type + = 0> + IteratorType erase(IteratorType first, IteratorType last) { // make sure iterator fits the current value - if (this != first.m_object or this != last.m_object) + if (JSON_UNLIKELY(this != first.m_object or this != last.m_object)) { - throw std::domain_error("iterators do not fit current value"); + JSON_THROW(invalid_iterator::create(203, "iterators do not fit current value")); } - InteratorType result = end(); + IteratorType result = end(); switch (m_type) { @@ -3941,24 +10813,27 @@ class basic_json case value_t::number_unsigned: case value_t::string: { - if (not first.m_it.primitive_iterator.is_begin() or not last.m_it.primitive_iterator.is_end()) + if (JSON_LIKELY(not first.m_it.primitive_iterator.is_begin() + or not last.m_it.primitive_iterator.is_end())) { - throw std::out_of_range("iterators out of range"); + JSON_THROW(invalid_iterator::create(204, "iterators out of range")); } if (is_string()) { - delete m_value.string; + AllocatorType<string_t> alloc; + std::allocator_traits<decltype(alloc)>::destroy(alloc, m_value.string); + std::allocator_traits<decltype(alloc)>::deallocate(alloc, m_value.string, 1); m_value.string = nullptr; } m_type = value_t::null; + assert_invariant(); break; } case value_t::object: { - assert(m_value.object != nullptr); result.m_it.object_iterator = m_value.object->erase(first.m_it.object_iterator, last.m_it.object_iterator); break; @@ -3966,16 +10841,13 @@ class basic_json case value_t::array: { - assert(m_value.array != nullptr); result.m_it.array_iterator = m_value.array->erase(first.m_it.array_iterator, last.m_it.array_iterator); break; } default: - { - throw std::domain_error("cannot use erase() with " + type_name()); - } + JSON_THROW(type_error::create(307, "cannot use erase() with " + std::string(type_name()))); } return result; @@ -3995,15 +10867,15 @@ class basic_json @post References and iterators to the erased elements are invalidated. Other references and iterators are not affected. - @throw std::domain_error when called on a type other than JSON object; + @throw type_error.307 when called on a type other than JSON object; example: `"cannot use erase() with null"` @complexity `log(size()) + count(key)` @liveexample{The example shows the effect of `erase()`.,erase__key_type} - @sa @ref erase(InteratorType) -- removes the element at a given position - @sa @ref erase(InteratorType, InteratorType) -- removes the elements in + @sa @ref erase(IteratorType) -- removes the element at a given position + @sa @ref erase(IteratorType, IteratorType) -- removes the elements in the given range @sa @ref erase(const size_type) -- removes the element from an array at the given index @@ -4013,15 +10885,12 @@ class basic_json size_type erase(const typename object_t::key_type& key) { // this erase only works for objects - if (is_object()) + if (JSON_LIKELY(is_object())) { - assert(m_value.object != nullptr); return m_value.object->erase(key); } - else - { - throw std::domain_error("cannot use erase() with " + type_name()); - } + + JSON_THROW(type_error::create(307, "cannot use erase() with " + std::string(type_name()))); } /*! @@ -4031,17 +10900,17 @@ class basic_json @param[in] idx index of the element to remove - @throw std::domain_error when called on a type other than JSON array; + @throw type_error.307 when called on a type other than JSON object; example: `"cannot use erase() with null"` - @throw std::out_of_range when `idx >= size()`; example: `"array index 17 + @throw out_of_range.401 when `idx >= size()`; example: `"array index 17 is out of range"` @complexity Linear in distance between @a idx and the end of the container. @liveexample{The example shows the effect of `erase()`.,erase__size_type} - @sa @ref erase(InteratorType) -- removes the element at a given position - @sa @ref erase(InteratorType, InteratorType) -- removes the elements in + @sa @ref erase(IteratorType) -- removes the element at a given position + @sa @ref erase(IteratorType, IteratorType) -- removes the elements in the given range @sa @ref erase(const typename object_t::key_type&) -- removes the element from an object at the given key @@ -4051,19 +10920,18 @@ class basic_json void erase(const size_type idx) { // this erase only works for arrays - if (is_array()) + if (JSON_LIKELY(is_array())) { - if (idx >= size()) + if (JSON_UNLIKELY(idx >= size())) { - throw std::out_of_range("array index " + std::to_string(idx) + " is out of range"); + JSON_THROW(out_of_range::create(401, "array index " + std::to_string(idx) + " is out of range")); } - assert(m_value.array != nullptr); m_value.array->erase(m_value.array->begin() + static_cast<difference_type>(idx)); } else { - throw std::domain_error("cannot use erase() with " + type_name()); + JSON_THROW(type_error::create(307, "cannot use erase() with " + std::string(type_name()))); } } @@ -4084,10 +10952,14 @@ class basic_json element is not found or the JSON value is not an object, end() is returned. - @param[in] key key value of the element to search for + @note This method always returns @ref end() when executed on a JSON type + that is not an object. + + @param[in] key key value of the element to search for. @return Iterator to an element with key equivalent to @a key. If no such - element is found, past-the-end (see end()) iterator is returned. + element is found or the JSON value is not an object, past-the-end (see + @ref end()) iterator is returned. @complexity Logarithmic in the size of the JSON object. @@ -4095,14 +10967,14 @@ class basic_json @since version 1.0.0 */ - iterator find(typename object_t::key_type key) + template<typename KeyT> + iterator find(KeyT&& key) { auto result = end(); if (is_object()) { - assert(m_value.object != nullptr); - result.m_it.object_iterator = m_value.object->find(key); + result.m_it.object_iterator = m_value.object->find(std::forward<KeyT>(key)); } return result; @@ -4110,16 +10982,16 @@ class basic_json /*! @brief find an element in a JSON object - @copydoc find(typename object_t::key_type) + @copydoc find(KeyT&&) */ - const_iterator find(typename object_t::key_type key) const + template<typename KeyT> + const_iterator find(KeyT&& key) const { auto result = cend(); if (is_object()) { - assert(m_value.object != nullptr); - result.m_it.object_iterator = m_value.object->find(key); + result.m_it.object_iterator = m_value.object->find(std::forward<KeyT>(key)); } return result; @@ -4132,6 +11004,9 @@ class basic_json default `std::map` type, the return value will always be `0` (@a key was not found) or `1` (@a key was found). + @note This method always returns `0` when executed on a JSON type that is + not an object. + @param[in] key key value of the element to count @return Number of elements with key @a key. If the JSON value is not an @@ -4143,11 +11018,11 @@ class basic_json @since version 1.0.0 */ - size_type count(typename object_t::key_type key) const + template<typename KeyT> + size_type count(KeyT&& key) const { // return 0 for all nonobject types - assert(not is_object() or m_value.object != nullptr); - return is_object() ? m_value.object->count(key) : 0; + return is_object() ? m_value.object->count(std::forward<KeyT>(key)) : 0; } /// @} @@ -4433,10 +11308,6 @@ class basic_json return const_reverse_iterator(cbegin()); } - private: - // forward declaration - template<typename IteratorType> class iteration_proxy; - public: /*! @brief wrapper to access iterator member functions in range-based for @@ -4446,20 +11317,62 @@ class basic_json reference to the JSON values is returned, so there is no access to the underlying iterator. + For loop without iterator_wrapper: + + @code{cpp} + for (auto it = j_object.begin(); it != j_object.end(); ++it) + { + std::cout << "key: " << it.key() << ", value:" << it.value() << '\n'; + } + @endcode + + Range-based for loop without iterator proxy: + + @code{cpp} + for (auto it : j_object) + { + // "it" is of type json::reference and has no key() member + std::cout << "value: " << it << '\n'; + } + @endcode + + Range-based for loop with iterator proxy: + + @code{cpp} + for (auto it : json::iterator_wrapper(j_object)) + { + std::cout << "key: " << it.key() << ", value:" << it.value() << '\n'; + } + @endcode + + @note When iterating over an array, `key()` will return the index of the + element as string (see example). + + @param[in] ref reference to a JSON value + @return iteration proxy object wrapping @a ref with an interface to use in + range-based for loops + + @liveexample{The following code shows how the wrapper is used,iterator_wrapper} + + @exceptionsafety Strong guarantee: if an exception is thrown, there are no + changes in the JSON value. + + @complexity Constant. + @note The name of this function is not yet final and may change in the future. */ - static iteration_proxy<iterator> iterator_wrapper(reference cont) + static iteration_proxy<iterator> iterator_wrapper(reference ref) { - return iteration_proxy<iterator>(cont); + return iteration_proxy<iterator>(ref); } /*! @copydoc iterator_wrapper(reference) */ - static iteration_proxy<const_iterator> iterator_wrapper(const_reference cont) + static iteration_proxy<const_iterator> iterator_wrapper(const_reference ref) { - return iteration_proxy<const_iterator>(cont); + return iteration_proxy<const_iterator>(ref); } /// @} @@ -4473,9 +11386,9 @@ class basic_json /// @{ /*! - @brief checks whether the container is empty + @brief checks whether the container is empty. - Checks if a JSON value has no elements. + Checks if a JSON value has no elements (i.e. whether its @ref size is `0`). @return The return value depends on the different types and is defined as follows: @@ -4488,19 +11401,27 @@ class basic_json object | result of function `object_t::empty()` array | result of function `array_t::empty()` + @liveexample{The following code uses `empty()` to check if a JSON + object contains any elements.,empty} + @complexity Constant, as long as @ref array_t and @ref object_t satisfy the Container concept; that is, their `empty()` functions have constant complexity. + @iterators No changes. + + @exceptionsafety No-throw guarantee: this function never throws exceptions. + + @note This function does not return whether a string stored as JSON value + is empty - it returns whether the JSON container itself is empty which is + false in the case of a string. + @requirement This function helps `basic_json` satisfying the [Container](http://en.cppreference.com/w/cpp/concept/Container) requirements: - The complexity is constant. - Has the semantics of `begin() == end()`. - @liveexample{The following code uses `empty()` to check if a JSON - object contains any elements.,empty} - @sa @ref size() -- returns the number of elements @since version 1.0.0 @@ -4517,13 +11438,13 @@ class basic_json case value_t::array: { - assert(m_value.array != nullptr); + // delegate call to array_t::empty() return m_value.array->empty(); } case value_t::object: { - assert(m_value.object != nullptr); + // delegate call to object_t::empty() return m_value.object->empty(); } @@ -4551,19 +11472,27 @@ class basic_json object | result of function object_t::size() array | result of function array_t::size() + @liveexample{The following code calls `size()` on the different value + types.,size} + @complexity Constant, as long as @ref array_t and @ref object_t satisfy the Container concept; that is, their size() functions have constant complexity. + @iterators No changes. + + @exceptionsafety No-throw guarantee: this function never throws exceptions. + + @note This function does not return the length of a string stored as JSON + value - it returns the number of elements in the JSON value which is 1 in + the case of a string. + @requirement This function helps `basic_json` satisfying the [Container](http://en.cppreference.com/w/cpp/concept/Container) requirements: - The complexity is constant. - Has the semantics of `std::distance(begin(), end())`. - @liveexample{The following code calls `size()` on the different value - types.,size} - @sa @ref empty() -- checks whether the container is empty @sa @ref max_size() -- returns the maximal number of elements @@ -4581,13 +11510,13 @@ class basic_json case value_t::array: { - assert(m_value.array != nullptr); + // delegate call to array_t::size() return m_value.array->size(); } case value_t::object: { - assert(m_value.object != nullptr); + // delegate call to object_t::size() return m_value.object->size(); } @@ -4617,10 +11546,17 @@ class basic_json object | result of function `object_t::max_size()` array | result of function `array_t::max_size()` + @liveexample{The following code calls `max_size()` on the different value + types. Note the output is implementation specific.,max_size} + @complexity Constant, as long as @ref array_t and @ref object_t satisfy the Container concept; that is, their `max_size()` functions have constant complexity. + @iterators No changes. + + @exceptionsafety No-throw guarantee: this function never throws exceptions. + @requirement This function helps `basic_json` satisfying the [Container](http://en.cppreference.com/w/cpp/concept/Container) requirements: @@ -4628,9 +11564,6 @@ class basic_json - Has the semantics of returning `b.size()` where `b` is the largest possible JSON value. - @liveexample{The following code calls `max_size()` on the different value - types. Note the output is implementation specific.,max_size} - @sa @ref size() -- returns the number of elements @since version 1.0.0 @@ -4641,13 +11574,13 @@ class basic_json { case value_t::array: { - assert(m_value.array != nullptr); + // delegate call to array_t::max_size() return m_value.array->max_size(); } case value_t::object: { - assert(m_value.object != nullptr); + // delegate call to object_t::max_size() return m_value.object->max_size(); } @@ -4673,7 +11606,8 @@ class basic_json @brief clears the contents Clears the content of a JSON value and resets it to the default value as - if @ref basic_json(value_t) would have been called: + if @ref basic_json(value_t) would have been called with the current value + type from @ref type(): Value type | initial value ----------- | ------------- @@ -4684,14 +11618,24 @@ class basic_json object | `{}` array | `[]` - @note Floating-point numbers are set to `0.0` which will be serialized to - `0`. The vale type remains @ref number_float_t. - - @complexity Linear in the size of the JSON value. + @post Has the same effect as calling + @code {.cpp} + *this = basic_json(type()); + @endcode @liveexample{The example below shows the effect of `clear()` to different JSON types.,clear} + @complexity Linear in the size of the JSON value. + + @iterators All iterators, pointers and references related to this container + are invalidated. + + @exceptionsafety No-throw guarantee: this function never throws exceptions. + + @sa @ref basic_json(value_t) -- constructor that creates an object with the + same value than calling `clear()` + @since version 1.0.0 */ void clear() noexcept @@ -4724,29 +11668,24 @@ class basic_json case value_t::string: { - assert(m_value.string != nullptr); m_value.string->clear(); break; } case value_t::array: { - assert(m_value.array != nullptr); m_value.array->clear(); break; } case value_t::object: { - assert(m_value.object != nullptr); m_value.object->clear(); break; } default: - { break; - } } } @@ -4759,7 +11698,7 @@ class basic_json @param[in] val the value to add to the JSON array - @throw std::domain_error when called on a type other than JSON array or + @throw type_error.308 when called on a type other than JSON array or null; example: `"cannot use push_back() with number"` @complexity Amortized constant. @@ -4773,9 +11712,9 @@ class basic_json void push_back(basic_json&& val) { // push_back only works for null objects or arrays - if (not(is_null() or is_array())) + if (JSON_UNLIKELY(not(is_null() or is_array()))) { - throw std::domain_error("cannot use push_back() with " + type_name()); + JSON_THROW(type_error::create(308, "cannot use push_back() with " + std::string(type_name()))); } // transform null object into an array @@ -4783,10 +11722,10 @@ class basic_json { m_type = value_t::array; m_value = value_t::array; + assert_invariant(); } // add element to array (move semantics) - assert(m_value.array != nullptr); m_value.array->push_back(std::move(val)); // invalidate object val.m_type = value_t::null; @@ -4809,9 +11748,9 @@ class basic_json void push_back(const basic_json& val) { // push_back only works for null objects or arrays - if (not(is_null() or is_array())) + if (JSON_UNLIKELY(not(is_null() or is_array()))) { - throw std::domain_error("cannot use push_back() with " + type_name()); + JSON_THROW(type_error::create(308, "cannot use push_back() with " + std::string(type_name()))); } // transform null object into an array @@ -4819,10 +11758,10 @@ class basic_json { m_type = value_t::array; m_value = value_t::array; + assert_invariant(); } // add element to array - assert(m_value.array != nullptr); m_value.array->push_back(val); } @@ -4845,7 +11784,7 @@ class basic_json @param[in] val the value to add to the JSON object - @throw std::domain_error when called on a type other than JSON object or + @throw type_error.308 when called on a type other than JSON object or null; example: `"cannot use push_back() with number"` @complexity Logarithmic in the size of the container, O(log(`size()`)). @@ -4859,9 +11798,9 @@ class basic_json void push_back(const typename object_t::value_type& val) { // push_back only works for null objects or objects - if (not(is_null() or is_object())) + if (JSON_UNLIKELY(not(is_null() or is_object()))) { - throw std::domain_error("cannot use push_back() with " + type_name()); + JSON_THROW(type_error::create(308, "cannot use push_back() with " + std::string(type_name()))); } // transform null object into an object @@ -4869,10 +11808,10 @@ class basic_json { m_type = value_t::object; m_value = value_t::object; + assert_invariant(); } // add element to array - assert(m_value.object != nullptr); m_value.object->insert(val); } @@ -4899,7 +11838,7 @@ class basic_json @ref push_back(const typename object_t::value_type&). Otherwise, @a init is converted to a JSON value and added using @ref push_back(basic_json&&). - @param init an initializer list + @param[in] init an initializer list @complexity Linear in the size of the initializer list @a init. @@ -4911,12 +11850,13 @@ class basic_json @liveexample{The example shows how initializer lists are treated as objects when possible.,push_back__initializer_list} */ - void push_back(std::initializer_list<basic_json> init) + void push_back(initializer_list_t init) { - if (is_object() and init.size() == 2 and init.begin()->is_string()) + if (is_object() and init.size() == 2 and (*init.begin())->is_string()) { - const string_t key = *init.begin(); - push_back(typename object_t::value_type(key, *(init.begin() + 1))); + basic_json&& key = init.begin()->moved_or_copied(); + push_back(typename object_t::value_type( + std::move(key.get_ref<string_t&>()), (init.begin() + 1)->moved_or_copied())); } else { @@ -4926,15 +11866,111 @@ class basic_json /*! @brief add an object to an object - @copydoc push_back(std::initializer_list<basic_json>) + @copydoc push_back(initializer_list_t) */ - reference operator+=(std::initializer_list<basic_json> init) + reference operator+=(initializer_list_t init) { push_back(init); return *this; } /*! + @brief add an object to an array + + Creates a JSON value from the passed parameters @a args to the end of the + JSON value. If the function is called on a JSON null value, an empty array + is created before appending the value created from @a args. + + @param[in] args arguments to forward to a constructor of @ref basic_json + @tparam Args compatible types to create a @ref basic_json object + + @throw type_error.311 when called on a type other than JSON array or + null; example: `"cannot use emplace_back() with number"` + + @complexity Amortized constant. + + @liveexample{The example shows how `push_back()` can be used to add + elements to a JSON array. Note how the `null` value was silently converted + to a JSON array.,emplace_back} + + @since version 2.0.8 + */ + template<class... Args> + void emplace_back(Args&& ... args) + { + // emplace_back only works for null objects or arrays + if (JSON_UNLIKELY(not(is_null() or is_array()))) + { + JSON_THROW(type_error::create(311, "cannot use emplace_back() with " + std::string(type_name()))); + } + + // transform null object into an array + if (is_null()) + { + m_type = value_t::array; + m_value = value_t::array; + assert_invariant(); + } + + // add element to array (perfect forwarding) + m_value.array->emplace_back(std::forward<Args>(args)...); + } + + /*! + @brief add an object to an object if key does not exist + + Inserts a new element into a JSON object constructed in-place with the + given @a args if there is no element with the key in the container. If the + function is called on a JSON null value, an empty object is created before + appending the value created from @a args. + + @param[in] args arguments to forward to a constructor of @ref basic_json + @tparam Args compatible types to create a @ref basic_json object + + @return a pair consisting of an iterator to the inserted element, or the + already-existing element if no insertion happened, and a bool + denoting whether the insertion took place. + + @throw type_error.311 when called on a type other than JSON object or + null; example: `"cannot use emplace() with number"` + + @complexity Logarithmic in the size of the container, O(log(`size()`)). + + @liveexample{The example shows how `emplace()` can be used to add elements + to a JSON object. Note how the `null` value was silently converted to a + JSON object. Further note how no value is added if there was already one + value stored with the same key.,emplace} + + @since version 2.0.8 + */ + template<class... Args> + std::pair<iterator, bool> emplace(Args&& ... args) + { + // emplace only works for null objects or arrays + if (JSON_UNLIKELY(not(is_null() or is_object()))) + { + JSON_THROW(type_error::create(311, "cannot use emplace() with " + std::string(type_name()))); + } + + // transform null object into an object + if (is_null()) + { + m_type = value_t::object; + m_value = value_t::object; + assert_invariant(); + } + + // add element to array (perfect forwarding) + auto res = m_value.object->emplace(std::forward<Args>(args)...); + // create result iterator and set iterator to the result of emplace + auto it = begin(); + it.m_it.object_iterator = res.first; + + // return pair of iterator and boolean + return {it, res.second}; + } + + /*! @brief inserts element Inserts element @a val before iterator @a pos. @@ -4944,13 +11980,13 @@ class basic_json @param[in] val element to insert @return iterator pointing to the inserted @a val. - @throw std::domain_error if called on JSON values other than arrays; + @throw type_error.309 if called on JSON values other than arrays; example: `"cannot use insert() with string"` - @throw std::domain_error if @a pos is not an iterator of *this; example: - `"iterator does not fit current value"` + @throw invalid_iterator.202 if @a pos is not an iterator of *this; + example: `"iterator does not fit current value"` - @complexity Constant plus linear in the distance between pos and end of the - container. + @complexity Constant plus linear in the distance between @a pos and end of + the container. @liveexample{The example shows how `insert()` is used.,insert} @@ -4959,24 +11995,21 @@ class basic_json iterator insert(const_iterator pos, const basic_json& val) { // insert only works for arrays - if (is_array()) + if (JSON_LIKELY(is_array())) { // check if iterator pos fits to this JSON value - if (pos.m_object != this) + if (JSON_UNLIKELY(pos.m_object != this)) { - throw std::domain_error("iterator does not fit current value"); + JSON_THROW(invalid_iterator::create(202, "iterator does not fit current value")); } // insert to array and return iterator iterator result(this); - assert(m_value.array != nullptr); result.m_it.array_iterator = m_value.array->insert(pos.m_it.array_iterator, val); return result; } - else - { - throw std::domain_error("cannot use insert() with " + type_name()); - } + + JSON_THROW(type_error::create(309, "cannot use insert() with " + std::string(type_name()))); } /*! @@ -5000,10 +12033,10 @@ class basic_json @return iterator pointing to the first element inserted, or @a pos if `cnt==0` - @throw std::domain_error if called on JSON values other than arrays; - example: `"cannot use insert() with string"` - @throw std::domain_error if @a pos is not an iterator of *this; example: - `"iterator does not fit current value"` + @throw type_error.309 if called on JSON values other than arrays; example: + `"cannot use insert() with string"` + @throw invalid_iterator.202 if @a pos is not an iterator of *this; + example: `"iterator does not fit current value"` @complexity Linear in @a cnt plus linear in the distance between @a pos and end of the container. @@ -5015,24 +12048,21 @@ class basic_json iterator insert(const_iterator pos, size_type cnt, const basic_json& val) { // insert only works for arrays - if (is_array()) + if (JSON_LIKELY(is_array())) { // check if iterator pos fits to this JSON value - if (pos.m_object != this) + if (JSON_UNLIKELY(pos.m_object != this)) { - throw std::domain_error("iterator does not fit current value"); + JSON_THROW(invalid_iterator::create(202, "iterator does not fit current value")); } // insert to array and return iterator iterator result(this); - assert(m_value.array != nullptr); result.m_it.array_iterator = m_value.array->insert(pos.m_it.array_iterator, cnt, val); return result; } - else - { - throw std::domain_error("cannot use insert() with " + type_name()); - } + + JSON_THROW(type_error::create(309, "cannot use insert() with " + std::string(type_name()))); } /*! @@ -5045,13 +12075,13 @@ class basic_json @param[in] first begin of the range of elements to insert @param[in] last end of the range of elements to insert - @throw std::domain_error if called on JSON values other than arrays; - example: `"cannot use insert() with string"` - @throw std::domain_error if @a pos is not an iterator of *this; example: - `"iterator does not fit current value"` - @throw std::domain_error if @a first and @a last do not belong to the same - JSON value; example: `"iterators do not fit"` - @throw std::domain_error if @a first or @a last are iterators into + @throw type_error.309 if called on JSON values other than arrays; example: + `"cannot use insert() with string"` + @throw invalid_iterator.202 if @a pos is not an iterator of *this; + example: `"iterator does not fit current value"` + @throw invalid_iterator.210 if @a first and @a last do not belong to the + same JSON value; example: `"iterators do not fit"` + @throw invalid_iterator.211 if @a first or @a last are iterators into container for which insert is called; example: `"passed iterators may not belong to container"` @@ -5068,31 +12098,30 @@ class basic_json iterator insert(const_iterator pos, const_iterator first, const_iterator last) { // insert only works for arrays - if (not is_array()) + if (JSON_UNLIKELY(not is_array())) { - throw std::domain_error("cannot use insert() with " + type_name()); + JSON_THROW(type_error::create(309, "cannot use insert() with " + std::string(type_name()))); } // check if iterator pos fits to this JSON value - if (pos.m_object != this) + if (JSON_UNLIKELY(pos.m_object != this)) { - throw std::domain_error("iterator does not fit current value"); + JSON_THROW(invalid_iterator::create(202, "iterator does not fit current value")); } // check if range iterators belong to the same JSON object - if (first.m_object != last.m_object) + if (JSON_UNLIKELY(first.m_object != last.m_object)) { - throw std::domain_error("iterators do not fit"); + JSON_THROW(invalid_iterator::create(210, "iterators do not fit")); } - if (first.m_object == this or last.m_object == this) + if (JSON_UNLIKELY(first.m_object == this)) { - throw std::domain_error("passed iterators may not belong to container"); + JSON_THROW(invalid_iterator::create(211, "passed iterators may not belong to container")); } // insert to array and return iterator iterator result(this); - assert(m_value.array != nullptr); result.m_it.array_iterator = m_value.array->insert( pos.m_it.array_iterator, first.m_it.array_iterator, @@ -5109,10 +12138,10 @@ class basic_json the end() iterator @param[in] ilist initializer list to insert the values from - @throw std::domain_error if called on JSON values other than arrays; - example: `"cannot use insert() with string"` - @throw std::domain_error if @a pos is not an iterator of *this; example: - `"iterator does not fit current value"` + @throw type_error.309 if called on JSON values other than arrays; example: + `"cannot use insert() with string"` + @throw invalid_iterator.202 if @a pos is not an iterator of *this; + example: `"iterator does not fit current value"` @return iterator pointing to the first element inserted, or @a pos if `ilist` is empty @@ -5124,28 +12153,177 @@ class basic_json @since version 1.0.0 */ - iterator insert(const_iterator pos, std::initializer_list<basic_json> ilist) + iterator insert(const_iterator pos, initializer_list_t ilist) { // insert only works for arrays - if (not is_array()) + if (JSON_UNLIKELY(not is_array())) { - throw std::domain_error("cannot use insert() with " + type_name()); + JSON_THROW(type_error::create(309, "cannot use insert() with " + std::string(type_name()))); } // check if iterator pos fits to this JSON value - if (pos.m_object != this) + if (JSON_UNLIKELY(pos.m_object != this)) { - throw std::domain_error("iterator does not fit current value"); + JSON_THROW(invalid_iterator::create(202, "iterator does not fit current value")); } // insert to array and return iterator iterator result(this); - assert(m_value.array != nullptr); - result.m_it.array_iterator = m_value.array->insert(pos.m_it.array_iterator, ilist); + result.m_it.array_iterator = m_value.array->insert(pos.m_it.array_iterator, ilist.begin(), ilist.end()); return result; } /*! + @brief inserts elements + + Inserts elements from range `[first, last)`. + + @param[in] first begin of the range of elements to insert + @param[in] last end of the range of elements to insert + + @throw type_error.309 if called on JSON values other than objects; example: + `"cannot use insert() with string"` + @throw invalid_iterator.202 if iterator @a first or @a last does does not + point to an object; example: `"iterators first and last must point to + objects"` + @throw invalid_iterator.210 if @a first and @a last do not belong to the + same JSON value; example: `"iterators do not fit"` + + @complexity Logarithmic: `O(N*log(size() + N))`, where `N` is the number + of elements to insert. + + @liveexample{The example shows how `insert()` is used.,insert__range_object} + + @since version 3.0.0 + */ + void insert(const_iterator first, const_iterator last) + { + // insert only works for objects + if (JSON_UNLIKELY(not is_object())) + { + JSON_THROW(type_error::create(309, "cannot use insert() with " + std::string(type_name()))); + } + + // check if range iterators belong to the same JSON object + if (JSON_UNLIKELY(first.m_object != last.m_object)) + { + JSON_THROW(invalid_iterator::create(210, "iterators do not fit")); + } + + // passed iterators must belong to objects + if (JSON_UNLIKELY(not first.m_object->is_object())) + { + JSON_THROW(invalid_iterator::create(202, "iterators first and last must point to objects")); + } + + m_value.object->insert(first.m_it.object_iterator, last.m_it.object_iterator); + } + + /*! + @brief updates a JSON object from another object, overwriting existing keys + + Inserts all values from JSON object @a j and overwrites existing keys. + + @param[in] j JSON object to read values from + + @throw type_error.312 if called on JSON values other than objects; example: + `"cannot use update() with string"` + + @complexity O(N*log(size() + N)), where N is the number of elements to + insert. + + @liveexample{The example shows how `update()` is used.,update} + + @sa https://docs.python.org/3.6/library/stdtypes.html#dict.update + + @since version 3.0.0 + */ + void update(const_reference j) + { + // implicitly convert null value to an empty object + if (is_null()) + { + m_type = value_t::object; + m_value.object = create<object_t>(); + assert_invariant(); + } + + if (JSON_UNLIKELY(not is_object())) + { + JSON_THROW(type_error::create(312, "cannot use update() with " + std::string(type_name()))); + } + if (JSON_UNLIKELY(not j.is_object())) + { + JSON_THROW(type_error::create(312, "cannot use update() with " + std::string(j.type_name()))); + } + + for (auto it = j.cbegin(); it != j.cend(); ++it) + { + m_value.object->operator[](it.key()) = it.value(); + } + } + + /*! + @brief updates a JSON object from another object, overwriting existing keys + + Inserts all values from from range `[first, last)` and overwrites existing + keys. + + @param[in] first begin of the range of elements to insert + @param[in] last end of the range of elements to insert + + @throw type_error.312 if called on JSON values other than objects; example: + `"cannot use update() with string"` + @throw invalid_iterator.202 if iterator @a first or @a last does does not + point to an object; example: `"iterators first and last must point to + objects"` + @throw invalid_iterator.210 if @a first and @a last do not belong to the + same JSON value; example: `"iterators do not fit"` + + @complexity O(N*log(size() + N)), where N is the number of elements to + insert. + + @liveexample{The example shows how `update()` is used__range.,update} + + @sa https://docs.python.org/3.6/library/stdtypes.html#dict.update + + @since version 3.0.0 + */ + void update(const_iterator first, const_iterator last) + { + // implicitly convert null value to an empty object + if (is_null()) + { + m_type = value_t::object; + m_value.object = create<object_t>(); + assert_invariant(); + } + + if (JSON_UNLIKELY(not is_object())) + { + JSON_THROW(type_error::create(312, "cannot use update() with " + std::string(type_name()))); + } + + // check if range iterators belong to the same JSON object + if (JSON_UNLIKELY(first.m_object != last.m_object)) + { + JSON_THROW(invalid_iterator::create(210, "iterators do not fit")); + } + + // passed iterators must belong to objects + if (JSON_UNLIKELY(not first.m_object->is_object() + or not first.m_object->is_object())) + { + JSON_THROW(invalid_iterator::create(202, "iterators first and last must point to objects")); + } + + for (auto it = first; it != last; ++it) + { + m_value.object->operator[](it.key()) = it.value(); + } + } + + /*! @brief exchanges the values Exchanges the contents of the JSON value with those of @a other. Does not @@ -5171,6 +12349,7 @@ class basic_json { std::swap(m_type, other.m_type); std::swap(m_value, other.m_value); + assert_invariant(); } /*! @@ -5183,7 +12362,7 @@ class basic_json @param[in,out] other array to exchange the contents with - @throw std::domain_error when JSON value is not an array; example: `"cannot + @throw type_error.310 when JSON value is not an array; example: `"cannot use swap() with string"` @complexity Constant. @@ -5196,14 +12375,13 @@ class basic_json void swap(array_t& other) { // swap only works for arrays - if (is_array()) + if (JSON_LIKELY(is_array())) { - assert(m_value.array != nullptr); std::swap(*(m_value.array), other); } else { - throw std::domain_error("cannot use swap() with " + type_name()); + JSON_THROW(type_error::create(310, "cannot use swap() with " + std::string(type_name()))); } } @@ -5217,7 +12395,7 @@ class basic_json @param[in,out] other object to exchange the contents with - @throw std::domain_error when JSON value is not an object; example: + @throw type_error.310 when JSON value is not an object; example: `"cannot use swap() with string"` @complexity Constant. @@ -5230,14 +12408,13 @@ class basic_json void swap(object_t& other) { // swap only works for objects - if (is_object()) + if (JSON_LIKELY(is_object())) { - assert(m_value.object != nullptr); std::swap(*(m_value.object), other); } else { - throw std::domain_error("cannot use swap() with " + type_name()); + JSON_THROW(type_error::create(310, "cannot use swap() with " + std::string(type_name()))); } } @@ -5251,7 +12428,7 @@ class basic_json @param[in,out] other string to exchange the contents with - @throw std::domain_error when JSON value is not a string; example: `"cannot + @throw type_error.310 when JSON value is not a string; example: `"cannot use swap() with boolean"` @complexity Constant. @@ -5264,20 +12441,19 @@ class basic_json void swap(string_t& other) { // swap only works for strings - if (is_string()) + if (JSON_LIKELY(is_string())) { - assert(m_value.string != nullptr); std::swap(*(m_value.string), other); } else { - throw std::domain_error("cannot use swap() with " + type_name()); + JSON_THROW(type_error::create(310, "cannot use swap() with " + std::string(type_name()))); } } /// @} - + public: ////////////////////////////////////////// // lexicographical comparison operators // ////////////////////////////////////////// @@ -5285,56 +12461,38 @@ class basic_json /// @name lexicographical comparison operators /// @{ - private: - /*! - @brief comparison operator for JSON types - - Returns an ordering that is similar to Python: - - order: null < boolean < number < object < array < string - - furthermore, each type is not smaller than itself - - @since version 1.0.0 - */ - friend bool operator<(const value_t lhs, const value_t rhs) noexcept - { - static constexpr std::array<uint8_t, 8> order = {{ - 0, // null - 3, // object - 4, // array - 5, // string - 1, // boolean - 2, // integer - 2, // unsigned - 2, // float - } - }; - - // discarded values are not comparable - if (lhs == value_t::discarded or rhs == value_t::discarded) - { - return false; - } - - return order[static_cast<std::size_t>(lhs)] < order[static_cast<std::size_t>(rhs)]; - } - - public: /*! @brief comparison: equal Compares two JSON values for equality according to the following rules: - Two JSON values are equal if (1) they are from the same type and (2) - their stored values are the same. + their stored values are the same according to their respective + `operator==`. - Integer and floating-point numbers are automatically converted before - comparison. Floating-point numbers are compared indirectly: two - floating-point numbers `f1` and `f2` are considered equal if neither - `f1 > f2` nor `f2 > f1` holds. + comparison. Note than two NaN values are always treated as unequal. - Two JSON null values are equal. + @note Floating-point inside JSON values numbers are compared with + `json::number_float_t::operator==` which is `double::operator==` by + default. To compare floating-point while respecting an epsilon, an alternative + [comparison function](https://github.com/mariokonrad/marnav/blob/master/src/marnav/math/floatingpoint.hpp#L34-#L39) + could be used, for instance + @code {.cpp} + template<typename T, typename = typename std::enable_if<std::is_floating_point<T>::value, T>::type> + inline bool is_same(T a, T b, T epsilon = std::numeric_limits<T>::epsilon()) noexcept + { + return std::abs(a - b) <= epsilon; + } + @endcode + + @note NaN values never compare equal to themselves or to other NaN values. + @param[in] lhs first JSON value to consider @param[in] rhs second JSON value to consider @return whether the values @a lhs and @a rhs are equal + @exceptionsafety No-throw guarantee: this function never throws exceptions. + @complexity Linear. @liveexample{The example demonstrates comparing several JSON @@ -5352,72 +12510,56 @@ class basic_json switch (lhs_type) { case value_t::array: - { - assert(lhs.m_value.array != nullptr); - assert(rhs.m_value.array != nullptr); - return *lhs.m_value.array == *rhs.m_value.array; - } + return (*lhs.m_value.array == *rhs.m_value.array); + case value_t::object: - { - assert(lhs.m_value.object != nullptr); - assert(rhs.m_value.object != nullptr); - return *lhs.m_value.object == *rhs.m_value.object; - } + return (*lhs.m_value.object == *rhs.m_value.object); + case value_t::null: - { return true; - } + case value_t::string: - { - assert(lhs.m_value.string != nullptr); - assert(rhs.m_value.string != nullptr); - return *lhs.m_value.string == *rhs.m_value.string; - } + return (*lhs.m_value.string == *rhs.m_value.string); + case value_t::boolean: - { - return lhs.m_value.boolean == rhs.m_value.boolean; - } + return (lhs.m_value.boolean == rhs.m_value.boolean); + case value_t::number_integer: - { - return lhs.m_value.number_integer == rhs.m_value.number_integer; - } + return (lhs.m_value.number_integer == rhs.m_value.number_integer); + case value_t::number_unsigned: - { - return lhs.m_value.number_unsigned == rhs.m_value.number_unsigned; - } + return (lhs.m_value.number_unsigned == rhs.m_value.number_unsigned); + case value_t::number_float: - { - return lhs.m_value.number_float == rhs.m_value.number_float; - } + return (lhs.m_value.number_float == rhs.m_value.number_float); + default: - { return false; - } } } else if (lhs_type == value_t::number_integer and rhs_type == value_t::number_float) { - return static_cast<number_float_t>(lhs.m_value.number_integer) == rhs.m_value.number_float; + return (static_cast<number_float_t>(lhs.m_value.number_integer) == rhs.m_value.number_float); } else if (lhs_type == value_t::number_float and rhs_type == value_t::number_integer) { - return lhs.m_value.number_float == static_cast<number_float_t>(rhs.m_value.number_integer); + return (lhs.m_value.number_float == static_cast<number_float_t>(rhs.m_value.number_integer)); } else if (lhs_type == value_t::number_unsigned and rhs_type == value_t::number_float) { - return static_cast<number_float_t>(lhs.m_value.number_unsigned) == rhs.m_value.number_float; + return (static_cast<number_float_t>(lhs.m_value.number_unsigned) == rhs.m_value.number_float); } else if (lhs_type == value_t::number_float and rhs_type == value_t::number_unsigned) { - return lhs.m_value.number_float == static_cast<number_float_t>(rhs.m_value.number_unsigned); + return (lhs.m_value.number_float == static_cast<number_float_t>(rhs.m_value.number_unsigned)); } else if (lhs_type == value_t::number_unsigned and rhs_type == value_t::number_integer) { - return static_cast<number_integer_t>(lhs.m_value.number_unsigned) == rhs.m_value.number_integer; + return (static_cast<number_integer_t>(lhs.m_value.number_unsigned) == rhs.m_value.number_integer); } else if (lhs_type == value_t::number_integer and rhs_type == value_t::number_unsigned) { - return lhs.m_value.number_integer == static_cast<number_integer_t>(rhs.m_value.number_unsigned); + return (lhs.m_value.number_integer == static_cast<number_integer_t>(rhs.m_value.number_unsigned)); } return false; @@ -5425,34 +12567,24 @@ class basic_json /*! @brief comparison: equal - - The functions compares the given JSON value against a null pointer. As the - null pointer can be used to initialize a JSON value to null, a comparison - of JSON value @a v with a null pointer should be equivalent to call - `v.is_null()`. - - @param[in] v JSON value to consider - @return whether @a v is null - - @complexity Constant. - - @liveexample{The example compares several JSON types to the null pointer. - ,operator__equal__nullptr_t} - - @since version 1.0.0 + @copydoc operator==(const_reference, const_reference) */ - friend bool operator==(const_reference v, std::nullptr_t) noexcept + template<typename ScalarType, typename std::enable_if< + std::is_scalar<ScalarType>::value, int>::type = 0> + friend bool operator==(const_reference lhs, const ScalarType rhs) noexcept { - return v.is_null(); + return (lhs == basic_json(rhs)); } /*! @brief comparison: equal - @copydoc operator==(const_reference, std::nullptr_t) + @copydoc operator==(const_reference, const_reference) */ - friend bool operator==(std::nullptr_t, const_reference v) noexcept + template<typename ScalarType, typename std::enable_if< + std::is_scalar<ScalarType>::value, int>::type = 0> + friend bool operator==(const ScalarType lhs, const_reference rhs) noexcept { - return v.is_null(); + return (basic_json(lhs) == rhs); } /*! @@ -5466,6 +12598,8 @@ class basic_json @complexity Linear. + @exceptionsafety No-throw guarantee: this function never throws exceptions. + @liveexample{The example demonstrates comparing several JSON types.,operator__notequal} @@ -5478,34 +12612,24 @@ class basic_json /*! @brief comparison: not equal - - The functions compares the given JSON value against a null pointer. As the - null pointer can be used to initialize a JSON value to null, a comparison - of JSON value @a v with a null pointer should be equivalent to call - `not v.is_null()`. - - @param[in] v JSON value to consider - @return whether @a v is not null - - @complexity Constant. - - @liveexample{The example compares several JSON types to the null pointer. - ,operator__notequal__nullptr_t} - - @since version 1.0.0 + @copydoc operator!=(const_reference, const_reference) */ - friend bool operator!=(const_reference v, std::nullptr_t) noexcept + template<typename ScalarType, typename std::enable_if< + std::is_scalar<ScalarType>::value, int>::type = 0> + friend bool operator!=(const_reference lhs, const ScalarType rhs) noexcept { - return not v.is_null(); + return (lhs != basic_json(rhs)); } /*! @brief comparison: not equal - @copydoc operator!=(const_reference, std::nullptr_t) + @copydoc operator!=(const_reference, const_reference) */ - friend bool operator!=(std::nullptr_t, const_reference v) noexcept + template<typename ScalarType, typename std::enable_if< + std::is_scalar<ScalarType>::value, int>::type = 0> + friend bool operator!=(const ScalarType lhs, const_reference rhs) noexcept { - return not v.is_null(); + return (basic_json(lhs) != rhs); } /*! @@ -5527,6 +12651,8 @@ class basic_json @complexity Linear. + @exceptionsafety No-throw guarantee: this function never throws exceptions. + @liveexample{The example demonstrates comparing several JSON types.,operator__less} @@ -5542,47 +12668,31 @@ class basic_json switch (lhs_type) { case value_t::array: - { - assert(lhs.m_value.array != nullptr); - assert(rhs.m_value.array != nullptr); - return *lhs.m_value.array < *rhs.m_value.array; - } + return (*lhs.m_value.array) < (*rhs.m_value.array); + case value_t::object: - { - assert(lhs.m_value.object != nullptr); - assert(rhs.m_value.object != nullptr); return *lhs.m_value.object < *rhs.m_value.object; - } + case value_t::null: - { return false; - } + case value_t::string: - { - assert(lhs.m_value.string != nullptr); - assert(rhs.m_value.string != nullptr); return *lhs.m_value.string < *rhs.m_value.string; - } + case value_t::boolean: - { return lhs.m_value.boolean < rhs.m_value.boolean; - } + case value_t::number_integer: - { return lhs.m_value.number_integer < rhs.m_value.number_integer; - } + case value_t::number_unsigned: - { return lhs.m_value.number_unsigned < rhs.m_value.number_unsigned; - } + case value_t::number_float: - { return lhs.m_value.number_float < rhs.m_value.number_float; - } + default: - { return false; - } } } else if (lhs_type == value_t::number_integer and rhs_type == value_t::number_float) @@ -5617,6 +12727,28 @@ class basic_json } /*! + @brief comparison: less than + @copydoc operator<(const_reference, const_reference) + */ + template<typename ScalarType, typename std::enable_if< + std::is_scalar<ScalarType>::value, int>::type = 0> + friend bool operator<(const_reference lhs, const ScalarType rhs) noexcept + { + return (lhs < basic_json(rhs)); + } + + /*! + @brief comparison: less than + @copydoc operator<(const_reference, const_reference) + */ + template<typename ScalarType, typename std::enable_if< + std::is_scalar<ScalarType>::value, int>::type = 0> + friend bool operator<(const ScalarType lhs, const_reference rhs) noexcept + { + return (basic_json(lhs) < rhs); + } + + /*! @brief comparison: less than or equal Compares whether one JSON value @a lhs is less than or equal to another @@ -5628,6 +12760,8 @@ class basic_json @complexity Linear. + @exceptionsafety No-throw guarantee: this function never throws exceptions. + @liveexample{The example demonstrates comparing several JSON types.,operator__greater} @@ -5639,6 +12773,28 @@ class basic_json } /*! + @brief comparison: less than or equal + @copydoc operator<=(const_reference, const_reference) + */ + template<typename ScalarType, typename std::enable_if< + std::is_scalar<ScalarType>::value, int>::type = 0> + friend bool operator<=(const_reference lhs, const ScalarType rhs) noexcept + { + return (lhs <= basic_json(rhs)); + } + + /*! + @brief comparison: less than or equal + @copydoc operator<=(const_reference, const_reference) + */ + template<typename ScalarType, typename std::enable_if< + std::is_scalar<ScalarType>::value, int>::type = 0> + friend bool operator<=(const ScalarType lhs, const_reference rhs) noexcept + { + return (basic_json(lhs) <= rhs); + } + + /*! @brief comparison: greater than Compares whether one JSON value @a lhs is greater than another @@ -5650,6 +12806,8 @@ class basic_json @complexity Linear. + @exceptionsafety No-throw guarantee: this function never throws exceptions. + @liveexample{The example demonstrates comparing several JSON types.,operator__lessequal} @@ -5661,6 +12819,28 @@ class basic_json } /*! + @brief comparison: greater than + @copydoc operator>(const_reference, const_reference) + */ + template<typename ScalarType, typename std::enable_if< + std::is_scalar<ScalarType>::value, int>::type = 0> + friend bool operator>(const_reference lhs, const ScalarType rhs) noexcept + { + return (lhs > basic_json(rhs)); + } + + /*! + @brief comparison: greater than + @copydoc operator>(const_reference, const_reference) + */ + template<typename ScalarType, typename std::enable_if< + std::is_scalar<ScalarType>::value, int>::type = 0> + friend bool operator>(const ScalarType lhs, const_reference rhs) noexcept + { + return (basic_json(lhs) > rhs); + } + + /*! @brief comparison: greater than or equal Compares whether one JSON value @a lhs is greater than or equal to another @@ -5672,6 +12852,8 @@ class basic_json @complexity Linear. + @exceptionsafety No-throw guarantee: this function never throws exceptions. + @liveexample{The example demonstrates comparing several JSON types.,operator__greaterequal} @@ -5682,8 +12864,29 @@ class basic_json return not (lhs < rhs); } - /// @} + /*! + @brief comparison: greater than or equal + @copydoc operator>=(const_reference, const_reference) + */ + template<typename ScalarType, typename std::enable_if< + std::is_scalar<ScalarType>::value, int>::type = 0> + friend bool operator>=(const_reference lhs, const ScalarType rhs) noexcept + { + return (lhs >= basic_json(rhs)); + } + + /*! + @brief comparison: greater than or equal + @copydoc operator>=(const_reference, const_reference) + */ + template<typename ScalarType, typename std::enable_if< + std::is_scalar<ScalarType>::value, int>::type = 0> + friend bool operator>=(const ScalarType lhs, const_reference rhs) noexcept + { + return (basic_json(lhs) >= rhs); + } + /// @} /////////////////// // serialization // @@ -5696,23 +12899,32 @@ class basic_json @brief serialize to stream Serialize the given JSON value @a j to the output stream @a o. The JSON - value will be serialized using the @ref dump member function. The - indentation of the output can be controlled with the member variable - `width` of the output stream @a o. For instance, using the manipulator - `std::setw(4)` on @a o sets the indentation level to `4` and the - serialization result is the same as calling `dump(4)`. + value will be serialized using the @ref dump member function. + + - The indentation of the output can be controlled with the member variable + `width` of the output stream @a o. For instance, using the manipulator + `std::setw(4)` on @a o sets the indentation level to `4` and the + serialization result is the same as calling `dump(4)`. + + - The indentation character can be controlled with the member variable + `fill` of the output stream @a o. For instance, the manipulator + `std::setfill('\\t')` sets indentation to use a tab character rather than + the default space character. @param[in,out] o stream to serialize to @param[in] j JSON value to serialize @return the stream @a o + @throw type_error.316 if a string stored inside the JSON value is not + UTF-8 encoded + @complexity Linear. @liveexample{The example below shows the serialization with different parameters to `width` to adjust the indentation level.,operator_serialize} - @since version 1.0.0 + @since version 1.0.0; indentation character added in version 3.0.0 */ friend std::ostream& operator<<(std::ostream& o, const basic_json& j) { @@ -5724,14 +12936,20 @@ class basic_json o.width(0); // do the actual serialization - j.dump(o, pretty_print, static_cast<unsigned int>(indentation)); + serializer s(detail::output_adapter<char>(o), o.fill()); + s.dump(j, pretty_print, false, static_cast<unsigned int>(indentation)); return o; } /*! @brief serialize to stream - @copydoc operator<<(std::ostream&, const basic_json&) + @deprecated This stream operator is deprecated and will be removed in a + future version of the library. Please use + @ref operator<<(std::ostream&, const basic_json&) + instead; that is, replace calls like `j >> o;` with `o << j;`. + @since version 1.0.0; deprecated since version 3.0.0 */ + JSON_DEPRECATED friend std::ostream& operator>>(const basic_json& j, std::ostream& o) { return o << j; @@ -5748,69 +12966,179 @@ class basic_json /// @{ /*! - @brief deserialize from string - - @param[in] s string to read a serialized JSON value from - @param[in] cb a parser callback function of type @ref parser_callback_t + @brief deserialize from a compatible input + + This function reads from a compatible input. Examples are: + - an array of 1-byte values + - strings with character/literal type with size of 1 byte + - input streams + - container with contiguous storage of 1-byte values. Compatible container + types include `std::vector`, `std::string`, `std::array`, + `std::valarray`, and `std::initializer_list`. Furthermore, C-style + arrays can be used with `std::begin()`/`std::end()`. User-defined + containers can be used as long as they implement random-access iterators + and a contiguous storage. + + @pre Each element of the container has a size of 1 byte. Violating this + precondition yields undefined behavior. **This precondition is enforced + with a static assertion.** + + @pre The container storage is contiguous. Violating this precondition + yields undefined behavior. **This precondition is enforced with an + assertion.** + @pre Each element of the container has a size of 1 byte. Violating this + precondition yields undefined behavior. **This precondition is enforced + with a static assertion.** + + @warning There is no way to enforce all preconditions at compile-time. If + the function is called with a noncompliant container and with + assertions switched off, the behavior is undefined and will most + likely yield segmentation violation. + + @param[in] i input to read from + @param[in] cb a parser callback function of type @ref parser_callback_t which is used to control the deserialization by filtering unwanted values (optional) @return result of the deserialization + @throw parse_error.101 if a parse error occurs; example: `""unexpected end + of input; expected string literal""` + @throw parse_error.102 if to_unicode fails or surrogate error + @throw parse_error.103 if to_unicode fails + @complexity Linear in the length of the input. The parser is a predictive LL(1) parser. The complexity can be higher if the parser callback function @a cb has a super-linear complexity. @note A UTF-8 byte order mark is silently ignored. + @liveexample{The example below demonstrates the `parse()` function reading + from an array.,parse__array__parser_callback_t} + @liveexample{The example below demonstrates the `parse()` function with and without callback function.,parse__string__parser_callback_t} - @sa @ref parse(std::istream&, parser_callback_t) for a version that reads - from an input stream + @liveexample{The example below demonstrates the `parse()` function with + and without callback function.,parse__istream__parser_callback_t} + + @liveexample{The example below demonstrates the `parse()` function reading + from a contiguous container.,parse__contiguouscontainer__parser_callback_t} - @since version 1.0.0 + @since version 2.0.3 (contiguous containers) */ - static basic_json parse(const string_t& s, parser_callback_t cb = nullptr) + static basic_json parse(detail::input_adapter i, + const parser_callback_t cb = nullptr, + const bool allow_exceptions = true) { - return parser(s, cb).parse(); + basic_json result; + parser(i, cb, allow_exceptions).parse(true, result); + return result; } /*! - @brief deserialize from stream + @copydoc basic_json parse(detail::input_adapter, const parser_callback_t) + */ + static basic_json parse(detail::input_adapter& i, + const parser_callback_t cb = nullptr, + const bool allow_exceptions = true) + { + basic_json result; + parser(i, cb, allow_exceptions).parse(true, result); + return result; + } + + static bool accept(detail::input_adapter i) + { + return parser(i).accept(true); + } + + static bool accept(detail::input_adapter& i) + { + return parser(i).accept(true); + } - @param[in,out] i stream to read a serialized JSON value from - @param[in] cb a parser callback function of type @ref parser_callback_t + /*! + @brief deserialize from an iterator range with contiguous storage + + This function reads from an iterator range of a container with contiguous + storage of 1-byte values. Compatible container types include + `std::vector`, `std::string`, `std::array`, `std::valarray`, and + `std::initializer_list`. Furthermore, C-style arrays can be used with + `std::begin()`/`std::end()`. User-defined containers can be used as long + as they implement random-access iterators and a contiguous storage. + + @pre The iterator range is contiguous. Violating this precondition yields + undefined behavior. **This precondition is enforced with an assertion.** + @pre Each element in the range has a size of 1 byte. Violating this + precondition yields undefined behavior. **This precondition is enforced + with a static assertion.** + + @warning There is no way to enforce all preconditions at compile-time. If + the function is called with noncompliant iterators and with + assertions switched off, the behavior is undefined and will most + likely yield segmentation violation. + + @tparam IteratorType iterator of container with contiguous storage + @param[in] first begin of the range to parse (included) + @param[in] last end of the range to parse (excluded) + @param[in] cb a parser callback function of type @ref parser_callback_t which is used to control the deserialization by filtering unwanted values (optional) + @param[in] allow_exceptions whether to throw exceptions in case of a + parse error (optional, true by default) @return result of the deserialization + @throw parse_error.101 in case of an unexpected token + @throw parse_error.102 if to_unicode fails or surrogate error + @throw parse_error.103 if to_unicode fails + @complexity Linear in the length of the input. The parser is a predictive LL(1) parser. The complexity can be higher if the parser callback function @a cb has a super-linear complexity. @note A UTF-8 byte order mark is silently ignored. - @liveexample{The example below demonstrates the `parse()` function with - and without callback function.,parse__istream__parser_callback_t} - - @sa @ref parse(const string_t&, parser_callback_t) for a version that - reads from a string + @liveexample{The example below demonstrates the `parse()` function reading + from an iterator range.,parse__iteratortype__parser_callback_t} - @since version 1.0.0 + @since version 2.0.3 */ - static basic_json parse(std::istream& i, parser_callback_t cb = nullptr) + template<class IteratorType, typename std::enable_if< + std::is_base_of< + std::random_access_iterator_tag, + typename std::iterator_traits<IteratorType>::iterator_category>::value, int>::type = 0> + static basic_json parse(IteratorType first, IteratorType last, + const parser_callback_t cb = nullptr, + const bool allow_exceptions = true) + { + basic_json result; + parser(detail::input_adapter(first, last), cb, allow_exceptions).parse(true, result); + return result; + } + + template<class IteratorType, typename std::enable_if< + std::is_base_of< + std::random_access_iterator_tag, + typename std::iterator_traits<IteratorType>::iterator_category>::value, int>::type = 0> + static bool accept(IteratorType first, IteratorType last) { - return parser(i, cb).parse(); + return parser(detail::input_adapter(first, last)).accept(true); } /*! - @copydoc parse(std::istream&, parser_callback_t) + @brief deserialize from stream + @deprecated This stream operator is deprecated and will be removed in a + future version of the library. Please use + @ref operator>>(std::istream&, basic_json&) + instead; that is, replace calls like `j << i;` with `i >> j;`. + @since version 1.0.0; deprecated since version 3.0.0 */ - static basic_json parse(std::istream&& i, parser_callback_t cb = nullptr) + JSON_DEPRECATED + friend std::istream& operator<<(basic_json& j, std::istream& i) { - return parser(i, cb).parse(); + return operator>>(i, j); } /*! @@ -5821,7 +13149,9 @@ class basic_json @param[in,out] i input stream to read a serialized JSON value from @param[in,out] j JSON value to write the deserialized input to - @throw std::invalid_argument in case of parse errors + @throw parse_error.101 in case of an unexpected token + @throw parse_error.102 if to_unicode fails or surrogate error + @throw parse_error.103 if to_unicode fails @complexity Linear in the length of the input. The parser is a predictive LL(1) parser. @@ -5831,448 +13161,76 @@ class basic_json @liveexample{The example below shows how a JSON value is constructed by reading a serialization from a stream.,operator_deserialize} - @sa parse(std::istream&, parser_callback_t) for a variant with a parser - callback function to filter values while parsing + @sa parse(std::istream&, const parser_callback_t) for a variant with a + parser callback function to filter values while parsing @since version 1.0.0 */ - friend std::istream& operator<<(basic_json& j, std::istream& i) - { - j = parser(i).parse(); - return i; - } - - /*! - @brief deserialize from stream - @copydoc operator<<(basic_json&, std::istream&) - */ friend std::istream& operator>>(std::istream& i, basic_json& j) { - j = parser(i).parse(); + parser(detail::input_adapter(i)).parse(false, j); return i; } /// @} - - private: /////////////////////////// // convenience functions // /////////////////////////// - /// return the type as string - string_t type_name() const noexcept - { - switch (m_type) - { - case value_t::null: - return "null"; - case value_t::object: - return "object"; - case value_t::array: - return "array"; - case value_t::string: - return "string"; - case value_t::boolean: - return "boolean"; - case value_t::discarded: - return "discarded"; - default: - return "number"; - } - } - /*! - @brief calculates the extra space to escape a JSON string - - @param[in] s the string to escape - @return the number of characters required to escape string @a s - - @complexity Linear in the length of string @a s. - */ - static std::size_t extra_space(const string_t& s) noexcept - { - std::size_t result = 0; + @brief return the type as string - for (const auto& c : s) - { - switch (c) - { - case '"': - case '\\': - case '\b': - case '\f': - case '\n': - case '\r': - case '\t': - { - // from c (1 byte) to \x (2 bytes) - result += 1; - break; - } + Returns the type name as string to be used in error messages - usually to + indicate that a function was called on a wrong JSON type. - default: - { - if (c >= 0x00 and c <= 0x1f) - { - // from c (1 byte) to \uxxxx (6 bytes) - result += 5; - } - break; - } - } - } + @return a string representation of a the @a m_type member: + Value type | return value + ----------- | ------------- + null | `"null"` + boolean | `"boolean"` + string | `"string"` + number | `"number"` (for all number types) + object | `"object"` + array | `"array"` + discarded | `"discarded"` - return result; - } + @exceptionsafety No-throw guarantee: this function never throws exceptions. - /*! - @brief escape a string + @complexity Constant. - Escape a string by replacing certain special characters by a sequence of - an escape character (backslash) and another character and other control - characters by a sequence of "\u" followed by a four-digit hex - representation. + @liveexample{The following code exemplifies `type_name()` for all JSON + types.,type_name} - @param[in] s the string to escape - @return the escaped string + @sa @ref type() -- return the type of the JSON value + @sa @ref operator value_t() -- return the type of the JSON value (implicit) - @complexity Linear in the length of string @a s. + @since version 1.0.0, public since 2.1.0, `const char*` and `noexcept` + since 3.0.0 */ - static string_t escape_string(const string_t& s) + const char* type_name() const noexcept { - const auto space = extra_space(s); - if (space == 0) { - return s; - } - - // create a result string of necessary size - string_t result(s.size() + space, '\\'); - std::size_t pos = 0; - - for (const auto& c : s) - { - switch (c) + switch (m_type) { - // quotation mark (0x22) - case '"': - { - result[pos + 1] = '"'; - pos += 2; - break; - } - - // reverse solidus (0x5c) - case '\\': - { - // nothing to change - pos += 2; - break; - } - - // backspace (0x08) - case '\b': - { - result[pos + 1] = 'b'; - pos += 2; - break; - } - - // formfeed (0x0c) - case '\f': - { - result[pos + 1] = 'f'; - pos += 2; - break; - } - - // newline (0x0a) - case '\n': - { - result[pos + 1] = 'n'; - pos += 2; - break; - } - - // carriage return (0x0d) - case '\r': - { - result[pos + 1] = 'r'; - pos += 2; - break; - } - - // horizontal tab (0x09) - case '\t': - { - result[pos + 1] = 't'; - pos += 2; - break; - } - + case value_t::null: + return "null"; + case value_t::object: + return "object"; + case value_t::array: + return "array"; + case value_t::string: + return "string"; + case value_t::boolean: + return "boolean"; + case value_t::discarded: + return "discarded"; default: - { - if (c >= 0x00 and c <= 0x1f) - { - // convert a number 0..15 to its hex representation - // (0..f) - const auto hexify = [](const int v) -> char - { - return (v < 10) - ? ('0' + static_cast<char>(v)) - : ('a' + static_cast<char>((v - 10) & 0x1f)); - }; - - // print character c as \uxxxx - for (const char m : - { 'u', '0', '0', hexify(c >> 4), hexify(c & 0x0f) - }) - { - result[++pos] = m; - } - - ++pos; - } - else - { - // all other characters are added as-is - result[pos++] = c; - } - break; - } + return "number"; } } - - return result; } - /*! - @brief internal implementation of the serialization function - - This function is called by the public member function dump and organizes - the serialization internally. The indentation level is propagated as - additional parameter. In case of arrays and objects, the function is - called recursively. Note that - - - strings and object keys are escaped using `escape_string()` - - integer numbers are converted implicitly via `operator<<` - - floating-point numbers are converted to a string using `"%g"` format - - @param[out] o stream to write to - @param[in] pretty_print whether the output shall be pretty-printed - @param[in] indent_step the indent level - @param[in] current_indent the current indent level (only used internally) - */ - void dump(std::ostream& o, - const bool pretty_print, - const unsigned int indent_step, - const unsigned int current_indent = 0) const - { - // variable to hold indentation for recursive calls - unsigned int new_indent = current_indent; - - switch (m_type) - { - case value_t::object: - { - assert(m_value.object != nullptr); - - if (m_value.object->empty()) - { - o << "{}"; - return; - } - - o << "{"; - - // increase indentation - if (pretty_print) - { - new_indent += indent_step; - o << "\n"; - } - - for (auto i = m_value.object->cbegin(); i != m_value.object->cend(); ++i) - { - if (i != m_value.object->cbegin()) - { - o << (pretty_print ? ",\n" : ","); - } - o << string_t(new_indent, ' ') << "\"" - << escape_string(i->first) << "\":" - << (pretty_print ? " " : ""); - i->second.dump(o, pretty_print, indent_step, new_indent); - } - - // decrease indentation - if (pretty_print) - { - new_indent -= indent_step; - o << "\n"; - } - - o << string_t(new_indent, ' ') + "}"; - return; - } - - case value_t::array: - { - assert(m_value.array != nullptr); - - if (m_value.array->empty()) - { - o << "[]"; - return; - } - - o << "["; - - // increase indentation - if (pretty_print) - { - new_indent += indent_step; - o << "\n"; - } - - for (auto i = m_value.array->cbegin(); i != m_value.array->cend(); ++i) - { - if (i != m_value.array->cbegin()) - { - o << (pretty_print ? ",\n" : ","); - } - o << string_t(new_indent, ' '); - i->dump(o, pretty_print, indent_step, new_indent); - } - - // decrease indentation - if (pretty_print) - { - new_indent -= indent_step; - o << "\n"; - } - - o << string_t(new_indent, ' ') << "]"; - return; - } - - case value_t::string: - { - assert(m_value.string != nullptr); - o << string_t("\"") << escape_string(*m_value.string) << "\""; - return; - } - - case value_t::boolean: - { - o << (m_value.boolean ? "true" : "false"); - return; - } - - case value_t::number_integer: - { - o << m_value.number_integer; - return; - } - - case value_t::number_unsigned: - { - o << m_value.number_unsigned; - return; - } - - case value_t::number_float: - { - // check if number was parsed from a string - if (m_type.bits.parsed) - { - // check if parsed number had an exponent given - if (m_type.bits.has_exp) - { - // buffer size: precision (2^8-1 = 255) + other ('-.e-xxx' = 7) + null (1) - char buf[263]; - int len; - - // handle capitalization of the exponent - if (m_type.bits.exp_cap) - { - len = snprintf(buf, sizeof(buf), "%.*E", - m_type.bits.precision, m_value.number_float) + 1; - } - else - { - len = snprintf(buf, sizeof(buf), "%.*e", - m_type.bits.precision, m_value.number_float) + 1; - } - - // remove '+' sign from the exponent if necessary - if (not m_type.bits.exp_plus) - { - if (len > static_cast<int>(sizeof(buf))) - { - len = sizeof(buf); - } - for (int i = 0; i < len; i++) - { - if (buf[i] == '+') - { - for (; i + 1 < len; i++) - { - buf[i] = buf[i + 1]; - } - } - } - } - - o << buf; - } - else - { - // no exponent - output as a decimal - std::stringstream ss; - ss.imbue(std::locale(std::locale(), new DecimalSeparator)); // fix locale problems - ss << std::setprecision(m_type.bits.precision) - << std::fixed << m_value.number_float; - o << ss.str(); - } - } - else - { - if (m_value.number_float == 0) - { - // special case for zero to get "0.0"/"-0.0" - o << (std::signbit(m_value.number_float) ? "-0.0" : "0.0"); - } - else - { - // Otherwise 6, 15 or 16 digits of precision allows - // round-trip IEEE 754 string->float->string, - // string->double->string or string->long - // double->string; to be safe, we read this value from - // std::numeric_limits<number_float_t>::digits10 - std::stringstream ss; - ss.imbue(std::locale(std::locale(), new DecimalSeparator)); // fix locale problems - ss << std::setprecision(std::numeric_limits<double>::digits10) - << m_value.number_float; - o << ss.str(); - } - } - return; - } - - case value_t::discarded: - { - o << "<discarded>"; - return; - } - - case value_t::null: - { - o << "null"; - return; - } - } - } private: ////////////////////// @@ -6280,3163 +13238,412 @@ class basic_json ////////////////////// /// the type of the current element - type_data_t m_type = value_t::null; + value_t m_type = value_t::null; /// the value of the current element json_value m_value = {}; + ////////////////////////////////////////// + // binary serialization/deserialization // + ////////////////////////////////////////// - private: - /////////////// - // iterators // - /////////////// + /// @name binary serialization/deserialization support + /// @{ + public: /*! - @brief an iterator for primitive JSON types - - This class models an iterator for primitive JSON types (boolean, number, - string). It's only purpose is to allow the iterator/const_iterator classes - to "iterate" over primitive values. Internally, the iterator is modeled by - a `difference_type` variable. Value begin_value (`0`) models the begin, - end_value (`1`) models past the end. - */ - class primitive_iterator_t - { - public: - /// set iterator to a defined beginning - void set_begin() noexcept - { - m_it = begin_value; - } - - /// set iterator to a defined past the end - void set_end() noexcept - { - m_it = end_value; - } - - /// return whether the iterator can be dereferenced - constexpr bool is_begin() const noexcept - { - return (m_it == begin_value); - } - - /// return whether the iterator is at end - constexpr bool is_end() const noexcept - { - return (m_it == end_value); - } + @brief create a CBOR serialization of a given JSON value + + Serializes a given JSON value @a j to a byte vector using the CBOR (Concise + Binary Object Representation) serialization format. CBOR is a binary + serialization format which aims to be more compact than JSON itself, yet + more efficient to parse. + + The library uses the following mapping from JSON values types to + CBOR types according to the CBOR specification (RFC 7049): + + JSON value type | value/range | CBOR type | first byte + --------------- | ------------------------------------------ | ---------------------------------- | --------------- + null | `null` | Null | 0xF6 + boolean | `true` | True | 0xF5 + boolean | `false` | False | 0xF4 + number_integer | -9223372036854775808..-2147483649 | Negative integer (8 bytes follow) | 0x3B + number_integer | -2147483648..-32769 | Negative integer (4 bytes follow) | 0x3A + number_integer | -32768..-129 | Negative integer (2 bytes follow) | 0x39 + number_integer | -128..-25 | Negative integer (1 byte follow) | 0x38 + number_integer | -24..-1 | Negative integer | 0x20..0x37 + number_integer | 0..23 | Integer | 0x00..0x17 + number_integer | 24..255 | Unsigned integer (1 byte follow) | 0x18 + number_integer | 256..65535 | Unsigned integer (2 bytes follow) | 0x19 + number_integer | 65536..4294967295 | Unsigned integer (4 bytes follow) | 0x1A + number_integer | 4294967296..18446744073709551615 | Unsigned integer (8 bytes follow) | 0x1B + number_unsigned | 0..23 | Integer | 0x00..0x17 + number_unsigned | 24..255 | Unsigned integer (1 byte follow) | 0x18 + number_unsigned | 256..65535 | Unsigned integer (2 bytes follow) | 0x19 + number_unsigned | 65536..4294967295 | Unsigned integer (4 bytes follow) | 0x1A + number_unsigned | 4294967296..18446744073709551615 | Unsigned integer (8 bytes follow) | 0x1B + number_float | *any value* | Double-Precision Float | 0xFB + string | *length*: 0..23 | UTF-8 string | 0x60..0x77 + string | *length*: 23..255 | UTF-8 string (1 byte follow) | 0x78 + string | *length*: 256..65535 | UTF-8 string (2 bytes follow) | 0x79 + string | *length*: 65536..4294967295 | UTF-8 string (4 bytes follow) | 0x7A + string | *length*: 4294967296..18446744073709551615 | UTF-8 string (8 bytes follow) | 0x7B + array | *size*: 0..23 | array | 0x80..0x97 + array | *size*: 23..255 | array (1 byte follow) | 0x98 + array | *size*: 256..65535 | array (2 bytes follow) | 0x99 + array | *size*: 65536..4294967295 | array (4 bytes follow) | 0x9A + array | *size*: 4294967296..18446744073709551615 | array (8 bytes follow) | 0x9B + object | *size*: 0..23 | map | 0xA0..0xB7 + object | *size*: 23..255 | map (1 byte follow) | 0xB8 + object | *size*: 256..65535 | map (2 bytes follow) | 0xB9 + object | *size*: 65536..4294967295 | map (4 bytes follow) | 0xBA + object | *size*: 4294967296..18446744073709551615 | map (8 bytes follow) | 0xBB + + @note The mapping is **complete** in the sense that any JSON value type + can be converted to a CBOR value. + + @note If NaN or Infinity are stored inside a JSON number, they are + serialized properly. This behavior differs from the @ref dump() + function which serializes NaN or Infinity to `null`. + + @note The following CBOR types are not used in the conversion: + - byte strings (0x40..0x5F) + - UTF-8 strings terminated by "break" (0x7F) + - arrays terminated by "break" (0x9F) + - maps terminated by "break" (0xBF) + - date/time (0xC0..0xC1) + - bignum (0xC2..0xC3) + - decimal fraction (0xC4) + - bigfloat (0xC5) + - tagged items (0xC6..0xD4, 0xD8..0xDB) + - expected conversions (0xD5..0xD7) + - simple values (0xE0..0xF3, 0xF8) + - undefined (0xF7) + - half and single-precision floats (0xF9-0xFA) + - break (0xFF) - /// return reference to the value to change and compare - operator difference_type& () noexcept - { - return m_it; - } - - /// return value to compare - constexpr operator difference_type () const noexcept - { - return m_it; - } + @param[in] j JSON value to serialize + @return MessagePack serialization as byte vector - private: - static constexpr difference_type begin_value = 0; - static constexpr difference_type end_value = begin_value + 1; + @complexity Linear in the size of the JSON value @a j. - /// iterator as signed integer type - difference_type m_it = std::numeric_limits<std::ptrdiff_t>::denorm_min(); - }; + @liveexample{The example shows the serialization of a JSON value to a byte + vector in CBOR format.,to_cbor} - /*! - @brief an iterator value + @sa http://cbor.io + @sa @ref from_cbor(const std::vector<uint8_t>&, const size_t) for the + analogous deserialization + @sa @ref to_msgpack(const basic_json&) for the related MessagePack format - @note This structure could easily be a union, but MSVC currently does not - allow unions members with complex constructors, see - https://github.com/nlohmann/json/pull/105. + @since version 2.0.9 */ - struct internal_iterator - { - /// iterator for JSON objects - typename object_t::iterator object_iterator; - /// iterator for JSON arrays - typename array_t::iterator array_iterator; - /// generic iterator for all other types - primitive_iterator_t primitive_iterator; - - /// create an uninitialized internal_iterator - internal_iterator() noexcept - : object_iterator(), array_iterator(), primitive_iterator() - {} - }; - - /// proxy class for the iterator_wrapper functions - template<typename IteratorType> - class iteration_proxy + static std::vector<uint8_t> to_cbor(const basic_json& j) { - private: - /// helper class for iteration - class iteration_proxy_internal - { - private: - /// the iterator - IteratorType anchor; - /// an index for arrays (used to create key names) - size_t array_index = 0; - - public: - explicit iteration_proxy_internal(IteratorType it) noexcept - : anchor(it) - {} - - /// dereference operator (needed for range-based for) - iteration_proxy_internal& operator*() - { - return *this; - } - - /// increment operator (needed for range-based for) - iteration_proxy_internal& operator++() - { - ++anchor; - ++array_index; - - return *this; - } - - /// inequality operator (needed for range-based for) - bool operator!= (const iteration_proxy_internal& o) const - { - return anchor != o.anchor; - } - - /// return key of the iterator - typename basic_json::string_t key() const - { - assert(anchor.m_object != nullptr); - - switch (anchor.m_object->type()) - { - // use integer array index as key - case value_t::array: - { - return std::to_string(array_index); - } - - // use key from the object - case value_t::object: - { - return anchor.key(); - } - - // use an empty key for all primitive types - default: - { - return ""; - } - } - } - - /// return value of the iterator - typename IteratorType::reference value() const - { - return anchor.value(); - } - }; - - /// the container to iterate - typename IteratorType::reference container; - - public: - /// construct iteration proxy from a container - explicit iteration_proxy(typename IteratorType::reference cont) - : container(cont) - {} - - /// return iterator begin (needed for range-based for) - iteration_proxy_internal begin() noexcept - { - return iteration_proxy_internal(container.begin()); - } - - /// return iterator end (needed for range-based for) - iteration_proxy_internal end() noexcept - { - return iteration_proxy_internal(container.end()); - } - }; - - public: - /*! - @brief a const random access iterator for the @ref basic_json class - - This class implements a const iterator for the @ref basic_json class. From - this class, the @ref iterator class is derived. - - @requirement The class satisfies the following concept requirements: - - [RandomAccessIterator](http://en.cppreference.com/w/cpp/concept/RandomAccessIterator): - The iterator that can be moved to point (forward and backward) to any - element in constant time. + std::vector<uint8_t> result; + to_cbor(j, result); + return result; + } - @since version 1.0.0 - */ - class const_iterator : public std::iterator<std::random_access_iterator_tag, const basic_json> + static void to_cbor(const basic_json& j, detail::output_adapter<uint8_t> o) { - /// allow basic_json to access private members - friend class basic_json; - - public: - /// the type of the values when the iterator is dereferenced - using value_type = typename basic_json::value_type; - /// a type to represent differences between iterators - using difference_type = typename basic_json::difference_type; - /// defines a pointer to the type iterated over (value_type) - using pointer = typename basic_json::const_pointer; - /// defines a reference to the type iterated over (value_type) - using reference = typename basic_json::const_reference; - /// the category of the iterator - using iterator_category = std::bidirectional_iterator_tag; - - /// default constructor - const_iterator() = default; - - /// constructor for a given JSON instance - explicit const_iterator(pointer object) noexcept - : m_object(object) - { - assert(m_object != nullptr); - - switch (m_object->m_type) - { - case basic_json::value_t::object: - { - m_it.object_iterator = typename object_t::iterator(); - break; - } - - case basic_json::value_t::array: - { - m_it.array_iterator = typename array_t::iterator(); - break; - } - - default: - { - m_it.primitive_iterator = primitive_iterator_t(); - break; - } - } - } - - /// copy constructor given a nonconst iterator - explicit const_iterator(const iterator& other) noexcept - : m_object(other.m_object) - { - assert(m_object != nullptr); - - switch (m_object->m_type) - { - case basic_json::value_t::object: - { - m_it.object_iterator = other.m_it.object_iterator; - break; - } - - case basic_json::value_t::array: - { - m_it.array_iterator = other.m_it.array_iterator; - break; - } - - default: - { - m_it.primitive_iterator = other.m_it.primitive_iterator; - break; - } - } - } - - /// copy constructor - const_iterator(const const_iterator& other) noexcept - : m_object(other.m_object), m_it(other.m_it) - {} - - /// copy assignment - const_iterator& operator=(const_iterator other) noexcept( - std::is_nothrow_move_constructible<pointer>::value and - std::is_nothrow_move_assignable<pointer>::value and - std::is_nothrow_move_constructible<internal_iterator>::value and - std::is_nothrow_move_assignable<internal_iterator>::value - ) - { - std::swap(m_object, other.m_object); - std::swap(m_it, other.m_it); - return *this; - } - - private: - /// set the iterator to the first value - void set_begin() noexcept - { - assert(m_object != nullptr); - - switch (m_object->m_type) - { - case basic_json::value_t::object: - { - assert(m_object->m_value.object != nullptr); - m_it.object_iterator = m_object->m_value.object->begin(); - break; - } - - case basic_json::value_t::array: - { - assert(m_object->m_value.array != nullptr); - m_it.array_iterator = m_object->m_value.array->begin(); - break; - } - - case basic_json::value_t::null: - { - // set to end so begin()==end() is true: null is empty - m_it.primitive_iterator.set_end(); - break; - } - - default: - { - m_it.primitive_iterator.set_begin(); - break; - } - } - } - - /// set the iterator past the last value - void set_end() noexcept - { - assert(m_object != nullptr); - - switch (m_object->m_type) - { - case basic_json::value_t::object: - { - assert(m_object->m_value.object != nullptr); - m_it.object_iterator = m_object->m_value.object->end(); - break; - } - - case basic_json::value_t::array: - { - assert(m_object->m_value.array != nullptr); - m_it.array_iterator = m_object->m_value.array->end(); - break; - } - - default: - { - m_it.primitive_iterator.set_end(); - break; - } - } - } - - public: - /// return a reference to the value pointed to by the iterator - reference operator*() const - { - assert(m_object != nullptr); - - switch (m_object->m_type) - { - case basic_json::value_t::object: - { - assert(m_object->m_value.object); - assert(m_it.object_iterator != m_object->m_value.object->end()); - return m_it.object_iterator->second; - } - - case basic_json::value_t::array: - { - assert(m_object->m_value.array); - assert(m_it.array_iterator != m_object->m_value.array->end()); - return *m_it.array_iterator; - } - - case basic_json::value_t::null: - { - throw std::out_of_range("cannot get value"); - } - - default: - { - if (m_it.primitive_iterator.is_begin()) - { - return *m_object; - } - else - { - throw std::out_of_range("cannot get value"); - } - } - } - } - - /// dereference the iterator - pointer operator->() const - { - assert(m_object != nullptr); - - switch (m_object->m_type) - { - case basic_json::value_t::object: - { - assert(m_object->m_value.object); - assert(m_it.object_iterator != m_object->m_value.object->end()); - return &(m_it.object_iterator->second); - } - - case basic_json::value_t::array: - { - assert(m_object->m_value.array); - assert(m_it.array_iterator != m_object->m_value.array->end()); - return &*m_it.array_iterator; - } - - default: - { - if (m_it.primitive_iterator.is_begin()) - { - return m_object; - } - else - { - throw std::out_of_range("cannot get value"); - } - } - } - } - - /// post-increment (it++) - const_iterator operator++(int) - { - auto result = *this; - ++(*this); - return result; - } - - /// pre-increment (++it) - const_iterator& operator++() - { - assert(m_object != nullptr); - - switch (m_object->m_type) - { - case basic_json::value_t::object: - { - ++m_it.object_iterator; - break; - } - - case basic_json::value_t::array: - { - ++m_it.array_iterator; - break; - } - - default: - { - ++m_it.primitive_iterator; - break; - } - } - - return *this; - } - - /// post-decrement (it--) - const_iterator operator--(int) - { - auto result = *this; - --(*this); - return result; - } - - /// pre-decrement (--it) - const_iterator& operator--() - { - assert(m_object != nullptr); - - switch (m_object->m_type) - { - case basic_json::value_t::object: - { - --m_it.object_iterator; - break; - } - - case basic_json::value_t::array: - { - --m_it.array_iterator; - break; - } - - default: - { - --m_it.primitive_iterator; - break; - } - } - - return *this; - } - - /// comparison: equal - bool operator==(const const_iterator& other) const - { - // if objects are not the same, the comparison is undefined - if (m_object != other.m_object) - { - throw std::domain_error("cannot compare iterators of different containers"); - } - - assert(m_object != nullptr); - - switch (m_object->m_type) - { - case basic_json::value_t::object: - { - return (m_it.object_iterator == other.m_it.object_iterator); - } - - case basic_json::value_t::array: - { - return (m_it.array_iterator == other.m_it.array_iterator); - } - - default: - { - return (m_it.primitive_iterator == other.m_it.primitive_iterator); - } - } - } - - /// comparison: not equal - bool operator!=(const const_iterator& other) const - { - return not operator==(other); - } - - /// comparison: smaller - bool operator<(const const_iterator& other) const - { - // if objects are not the same, the comparison is undefined - if (m_object != other.m_object) - { - throw std::domain_error("cannot compare iterators of different containers"); - } - - assert(m_object != nullptr); - - switch (m_object->m_type) - { - case basic_json::value_t::object: - { - throw std::domain_error("cannot compare order of object iterators"); - } - - case basic_json::value_t::array: - { - return (m_it.array_iterator < other.m_it.array_iterator); - } - - default: - { - return (m_it.primitive_iterator < other.m_it.primitive_iterator); - } - } - } - - /// comparison: less than or equal - bool operator<=(const const_iterator& other) const - { - return not other.operator < (*this); - } - - /// comparison: greater than - bool operator>(const const_iterator& other) const - { - return not operator<=(other); - } - - /// comparison: greater than or equal - bool operator>=(const const_iterator& other) const - { - return not operator<(other); - } - - /// add to iterator - const_iterator& operator+=(difference_type i) - { - assert(m_object != nullptr); - - switch (m_object->m_type) - { - case basic_json::value_t::object: - { - throw std::domain_error("cannot use offsets with object iterators"); - } - - case basic_json::value_t::array: - { - m_it.array_iterator += i; - break; - } - - default: - { - m_it.primitive_iterator += i; - break; - } - } - - return *this; - } - - /// subtract from iterator - const_iterator& operator-=(difference_type i) - { - return operator+=(-i); - } - - /// add to iterator - const_iterator operator+(difference_type i) - { - auto result = *this; - result += i; - return result; - } - - /// subtract from iterator - const_iterator operator-(difference_type i) - { - auto result = *this; - result -= i; - return result; - } - - /// return difference - difference_type operator-(const const_iterator& other) const - { - assert(m_object != nullptr); - - switch (m_object->m_type) - { - case basic_json::value_t::object: - { - throw std::domain_error("cannot use offsets with object iterators"); - } - - case basic_json::value_t::array: - { - return m_it.array_iterator - other.m_it.array_iterator; - } - - default: - { - return m_it.primitive_iterator - other.m_it.primitive_iterator; - } - } - } - - /// access to successor - reference operator[](difference_type n) const - { - assert(m_object != nullptr); - - switch (m_object->m_type) - { - case basic_json::value_t::object: - { - throw std::domain_error("cannot use operator[] for object iterators"); - } - - case basic_json::value_t::array: - { - return *(m_it.array_iterator + n); - } - - case basic_json::value_t::null: - { - throw std::out_of_range("cannot get value"); - } - - default: - { - if (m_it.primitive_iterator == -n) - { - return *m_object; - } - else - { - throw std::out_of_range("cannot get value"); - } - } - } - } - - /// return the key of an object iterator - typename object_t::key_type key() const - { - assert(m_object != nullptr); - - if (m_object->is_object()) - { - return m_it.object_iterator->first; - } - else - { - throw std::domain_error("cannot use key() for non-object iterators"); - } - } - - /// return the value of an iterator - reference value() const - { - return operator*(); - } - - private: - /// associated JSON instance - pointer m_object = nullptr; - /// the actual iterator of the associated instance - internal_iterator m_it = internal_iterator(); - }; - - /*! - @brief a mutable random access iterator for the @ref basic_json class - - @requirement The class satisfies the following concept requirements: - - [RandomAccessIterator](http://en.cppreference.com/w/cpp/concept/RandomAccessIterator): - The iterator that can be moved to point (forward and backward) to any - element in constant time. - - [OutputIterator](http://en.cppreference.com/w/cpp/concept/OutputIterator): - It is possible to write to the pointed-to element. + binary_writer<uint8_t>(o).write_cbor(j); + } - @since version 1.0.0 - */ - class iterator : public const_iterator + static void to_cbor(const basic_json& j, detail::output_adapter<char> o) { - public: - using base_iterator = const_iterator; - using pointer = typename basic_json::pointer; - using reference = typename basic_json::reference; - - /// default constructor - iterator() = default; - - /// constructor for a given JSON instance - explicit iterator(pointer object) noexcept - : base_iterator(object) - {} - - /// copy constructor - iterator(const iterator& other) noexcept - : base_iterator(other) - {} - - /// copy assignment - iterator& operator=(iterator other) noexcept( - std::is_nothrow_move_constructible<pointer>::value and - std::is_nothrow_move_assignable<pointer>::value and - std::is_nothrow_move_constructible<internal_iterator>::value and - std::is_nothrow_move_assignable<internal_iterator>::value - ) - { - base_iterator::operator=(other); - return *this; - } - - /// return a reference to the value pointed to by the iterator - reference operator*() const - { - return const_cast<reference>(base_iterator::operator*()); - } - - /// dereference the iterator - pointer operator->() const - { - return const_cast<pointer>(base_iterator::operator->()); - } - - /// post-increment (it++) - iterator operator++(int) - { - iterator result = *this; - base_iterator::operator++(); - return result; - } - - /// pre-increment (++it) - iterator& operator++() - { - base_iterator::operator++(); - return *this; - } - - /// post-decrement (it--) - iterator operator--(int) - { - iterator result = *this; - base_iterator::operator--(); - return result; - } - - /// pre-decrement (--it) - iterator& operator--() - { - base_iterator::operator--(); - return *this; - } - - /// add to iterator - iterator& operator+=(difference_type i) - { - base_iterator::operator+=(i); - return *this; - } - - /// subtract from iterator - iterator& operator-=(difference_type i) - { - base_iterator::operator-=(i); - return *this; - } - - /// add to iterator - iterator operator+(difference_type i) - { - auto result = *this; - result += i; - return result; - } - - /// subtract from iterator - iterator operator-(difference_type i) - { - auto result = *this; - result -= i; - return result; - } - - /// return difference - difference_type operator-(const iterator& other) const - { - return base_iterator::operator-(other); - } - - /// access to successor - reference operator[](difference_type n) const - { - return const_cast<reference>(base_iterator::operator[](n)); - } - - /// return the value of an iterator - reference value() const - { - return const_cast<reference>(base_iterator::value()); - } - }; + binary_writer<char>(o).write_cbor(j); + } /*! - @brief a template for a reverse iterator class - - @tparam Base the base iterator type to reverse. Valid types are @ref - iterator (to create @ref reverse_iterator) and @ref const_iterator (to - create @ref const_reverse_iterator). - - @requirement The class satisfies the following concept requirements: - - [RandomAccessIterator](http://en.cppreference.com/w/cpp/concept/RandomAccessIterator): - The iterator that can be moved to point (forward and backward) to any - element in constant time. - - [OutputIterator](http://en.cppreference.com/w/cpp/concept/OutputIterator): - It is possible to write to the pointed-to element (only if @a Base is - @ref iterator). - - @since version 1.0.0 - */ - template<typename Base> - class json_reverse_iterator : public std::reverse_iterator<Base> - { - public: - /// shortcut to the reverse iterator adaptor - using base_iterator = std::reverse_iterator<Base>; - /// the reference type for the pointed-to element - using reference = typename Base::reference; - - /// create reverse iterator from iterator - json_reverse_iterator(const typename base_iterator::iterator_type& it) noexcept - : base_iterator(it) - {} - - /// create reverse iterator from base class - json_reverse_iterator(const base_iterator& it) noexcept - : base_iterator(it) - {} + @brief create a MessagePack serialization of a given JSON value - /// post-increment (it++) - json_reverse_iterator operator++(int) - { - return base_iterator::operator++(1); - } + Serializes a given JSON value @a j to a byte vector using the MessagePack + serialization format. MessagePack is a binary serialization format which + aims to be more compact than JSON itself, yet more efficient to parse. - /// pre-increment (++it) - json_reverse_iterator& operator++() - { - base_iterator::operator++(); - return *this; - } + The library uses the following mapping from JSON values types to + MessagePack types according to the MessagePack specification: - /// post-decrement (it--) - json_reverse_iterator operator--(int) - { - return base_iterator::operator--(1); - } + JSON value type | value/range | MessagePack type | first byte + --------------- | --------------------------------- | ---------------- | ---------- + null | `null` | nil | 0xC0 + boolean | `true` | true | 0xC3 + boolean | `false` | false | 0xC2 + number_integer | -9223372036854775808..-2147483649 | int64 | 0xD3 + number_integer | -2147483648..-32769 | int32 | 0xD2 + number_integer | -32768..-129 | int16 | 0xD1 + number_integer | -128..-33 | int8 | 0xD0 + number_integer | -32..-1 | negative fixint | 0xE0..0xFF + number_integer | 0..127 | positive fixint | 0x00..0x7F + number_integer | 128..255 | uint 8 | 0xCC + number_integer | 256..65535 | uint 16 | 0xCD + number_integer | 65536..4294967295 | uint 32 | 0xCE + number_integer | 4294967296..18446744073709551615 | uint 64 | 0xCF + number_unsigned | 0..127 | positive fixint | 0x00..0x7F + number_unsigned | 128..255 | uint 8 | 0xCC + number_unsigned | 256..65535 | uint 16 | 0xCD + number_unsigned | 65536..4294967295 | uint 32 | 0xCE + number_unsigned | 4294967296..18446744073709551615 | uint 64 | 0xCF + number_float | *any value* | float 64 | 0xCB + string | *length*: 0..31 | fixstr | 0xA0..0xBF + string | *length*: 32..255 | str 8 | 0xD9 + string | *length*: 256..65535 | str 16 | 0xDA + string | *length*: 65536..4294967295 | str 32 | 0xDB + array | *size*: 0..15 | fixarray | 0x90..0x9F + array | *size*: 16..65535 | array 16 | 0xDC + array | *size*: 65536..4294967295 | array 32 | 0xDD + object | *size*: 0..15 | fix map | 0x80..0x8F + object | *size*: 16..65535 | map 16 | 0xDE + object | *size*: 65536..4294967295 | map 32 | 0xDF - /// pre-decrement (--it) - json_reverse_iterator& operator--() - { - base_iterator::operator--(); - return *this; - } + @note The mapping is **complete** in the sense that any JSON value type + can be converted to a MessagePack value. - /// add to iterator - json_reverse_iterator& operator+=(difference_type i) - { - base_iterator::operator+=(i); - return *this; - } + @note The following values can **not** be converted to a MessagePack value: + - strings with more than 4294967295 bytes + - arrays with more than 4294967295 elements + - objects with more than 4294967295 elements - /// add to iterator - json_reverse_iterator operator+(difference_type i) const - { - auto result = *this; - result += i; - return result; - } + @note The following MessagePack types are not used in the conversion: + - bin 8 - bin 32 (0xC4..0xC6) + - ext 8 - ext 32 (0xC7..0xC9) + - float 32 (0xCA) + - fixext 1 - fixext 16 (0xD4..0xD8) - /// subtract from iterator - json_reverse_iterator operator-(difference_type i) const - { - auto result = *this; - result -= i; - return result; - } + @note Any MessagePack output created @ref to_msgpack can be successfully + parsed by @ref from_msgpack. - /// return difference - difference_type operator-(const json_reverse_iterator& other) const - { - return this->base() - other.base(); - } + @note If NaN or Infinity are stored inside a JSON number, they are + serialized properly. This behavior differs from the @ref dump() + function which serializes NaN or Infinity to `null`. - /// access to successor - reference operator[](difference_type n) const - { - return *(this->operator+(n)); - } - - /// return the key of an object iterator - typename object_t::key_type key() const - { - auto it = --this->base(); - return it.key(); - } + @param[in] j JSON value to serialize + @return MessagePack serialization as byte vector - /// return the value of an iterator - reference value() const - { - auto it = --this->base(); - return it.operator * (); - } - }; + @complexity Linear in the size of the JSON value @a j. + @liveexample{The example shows the serialization of a JSON value to a byte + vector in MessagePack format.,to_msgpack} - private: - ////////////////////// - // lexer and parser // - ////////////////////// + @sa http://msgpack.org + @sa @ref from_msgpack(const std::vector<uint8_t>&, const size_t) for the + analogous deserialization + @sa @ref to_cbor(const basic_json& for the related CBOR format - /*! - @brief lexical analysis - - This class organizes the lexical analysis during JSON deserialization. The - core of it is a scanner generated by [re2c](http://re2c.org) that - processes a buffer and recognizes tokens according to RFC 7159. + @since version 2.0.9 */ - class lexer + static std::vector<uint8_t> to_msgpack(const basic_json& j) { - public: - /// token types for the parser - enum class token_type - { - uninitialized, ///< indicating the scanner is uninitialized - literal_true, ///< the `true` literal - literal_false, ///< the `false` literal - literal_null, ///< the `null` literal - value_string, ///< a string -- use get_string() for actual value - value_number, ///< a number -- use get_number() for actual value - begin_array, ///< the character for array begin `[` - begin_object, ///< the character for object begin `{` - end_array, ///< the character for array end `]` - end_object, ///< the character for object end `}` - name_separator, ///< the name separator `:` - value_separator, ///< the value separator `,` - parse_error, ///< indicating a parse error - end_of_input ///< indicating the end of the input buffer - }; - - /// the char type to use in the lexer - using lexer_char_t = unsigned char; - - /// constructor with a given buffer - explicit lexer(const string_t& s) noexcept - : m_stream(nullptr), m_buffer(s) - { - m_content = reinterpret_cast<const lexer_char_t*>(s.c_str()); - assert(m_content != nullptr); - m_start = m_cursor = m_content; - m_limit = m_content + s.size(); - } - - /// constructor with a given stream - explicit lexer(std::istream* s) noexcept - : m_stream(s), m_buffer() - { - assert(m_stream != nullptr); - getline(*m_stream, m_buffer); - m_content = reinterpret_cast<const lexer_char_t*>(m_buffer.c_str()); - assert(m_content != nullptr); - m_start = m_cursor = m_content; - m_limit = m_content + m_buffer.size(); - } - - /// default constructor - lexer() = default; - - // switch off unwanted functions - lexer(const lexer&) = delete; - lexer operator=(const lexer&) = delete; - - /*! - @brief create a string from a Unicode code point - - @param[in] codepoint1 the code point (can be high surrogate) - @param[in] codepoint2 the code point (can be low surrogate or 0) - - @return string representation of the code point - - @throw std::out_of_range if code point is > 0x10ffff; example: `"code - points above 0x10FFFF are invalid"` - @throw std::invalid_argument if the low surrogate is invalid; example: - `""missing or wrong low surrogate""` - - @see <http://en.wikipedia.org/wiki/UTF-8#Sample_code> - */ - static string_t to_unicode(const std::size_t codepoint1, - const std::size_t codepoint2 = 0) - { - // calculate the codepoint from the given code points - std::size_t codepoint = codepoint1; - - // check if codepoint1 is a high surrogate - if (codepoint1 >= 0xD800 and codepoint1 <= 0xDBFF) - { - // check if codepoint2 is a low surrogate - if (codepoint2 >= 0xDC00 and codepoint2 <= 0xDFFF) - { - codepoint = - // high surrogate occupies the most significant 22 bits - (codepoint1 << 10) - // low surrogate occupies the least significant 15 bits - + codepoint2 - // there is still the 0xD800, 0xDC00 and 0x10000 noise - // in the result so we have to subtract with: - // (0xD800 << 10) + DC00 - 0x10000 = 0x35FDC00 - - 0x35FDC00; - } - else - { - throw std::invalid_argument("missing or wrong low surrogate"); - } - } - - string_t result; - - if (codepoint < 0x80) - { - // 1-byte characters: 0xxxxxxx (ASCII) - result.append(1, static_cast<typename string_t::value_type>(codepoint)); - } - else if (codepoint <= 0x7ff) - { - // 2-byte characters: 110xxxxx 10xxxxxx - result.append(1, static_cast<typename string_t::value_type>(0xC0 | ((codepoint >> 6) & 0x1F))); - result.append(1, static_cast<typename string_t::value_type>(0x80 | (codepoint & 0x3F))); - } - else if (codepoint <= 0xffff) - { - // 3-byte characters: 1110xxxx 10xxxxxx 10xxxxxx - result.append(1, static_cast<typename string_t::value_type>(0xE0 | ((codepoint >> 12) & 0x0F))); - result.append(1, static_cast<typename string_t::value_type>(0x80 | ((codepoint >> 6) & 0x3F))); - result.append(1, static_cast<typename string_t::value_type>(0x80 | (codepoint & 0x3F))); - } - else if (codepoint <= 0x10ffff) - { - // 4-byte characters: 11110xxx 10xxxxxx 10xxxxxx 10xxxxxx - result.append(1, static_cast<typename string_t::value_type>(0xF0 | ((codepoint >> 18) & 0x07))); - result.append(1, static_cast<typename string_t::value_type>(0x80 | ((codepoint >> 12) & 0x3F))); - result.append(1, static_cast<typename string_t::value_type>(0x80 | ((codepoint >> 6) & 0x3F))); - result.append(1, static_cast<typename string_t::value_type>(0x80 | (codepoint & 0x3F))); - } - else - { - throw std::out_of_range("code points above 0x10FFFF are invalid"); - } - - return result; - } - - /// return name of values of type token_type (only used for errors) - static std::string token_type_name(token_type t) - { - switch (t) - { - case token_type::uninitialized: - return "<uninitialized>"; - case token_type::literal_true: - return "true literal"; - case token_type::literal_false: - return "false literal"; - case token_type::literal_null: - return "null literal"; - case token_type::value_string: - return "string literal"; - case token_type::value_number: - return "number literal"; - case token_type::begin_array: - return "'['"; - case token_type::begin_object: - return "'{'"; - case token_type::end_array: - return "']'"; - case token_type::end_object: - return "'}'"; - case token_type::name_separator: - return "':'"; - case token_type::value_separator: - return "','"; - case token_type::parse_error: - return "<parse error>"; - case token_type::end_of_input: - return "end of input"; - default: - { - // catch non-enum values - return "unknown token"; // LCOV_EXCL_LINE - } - } - } - - /*! - This function implements a scanner for JSON. It is specified using - regular expressions that try to follow RFC 7159 as close as possible. - These regular expressions are then translated into a minimized - deterministic finite automaton (DFA) by the tool - [re2c](http://re2c.org). As a result, the translated code for this - function consists of a large block of code with `goto` jumps. - - @return the class of the next token read from the buffer - */ - token_type scan() noexcept - { - // pointer for backtracking information - m_marker = nullptr; - - // remember the begin of the token - m_start = m_cursor; - assert(m_start != nullptr); - - - { - lexer_char_t yych; - unsigned int yyaccept = 0; - static const unsigned char yybm[] = - { - 0, 0, 0, 0, 0, 0, 0, 0, - 0, 32, 32, 0, 0, 32, 0, 0, - 128, 128, 128, 128, 128, 128, 128, 128, - 128, 128, 128, 128, 128, 128, 128, 128, - 160, 128, 0, 128, 128, 128, 128, 128, - 128, 128, 128, 128, 128, 128, 128, 128, - 192, 192, 192, 192, 192, 192, 192, 192, - 192, 192, 128, 128, 128, 128, 128, 128, - 128, 128, 128, 128, 128, 128, 128, 128, - 128, 128, 128, 128, 128, 128, 128, 128, - 128, 128, 128, 128, 128, 128, 128, 128, - 128, 128, 128, 128, 0, 128, 128, 128, - 128, 128, 128, 128, 128, 128, 128, 128, - 128, 128, 128, 128, 128, 128, 128, 128, - 128, 128, 128, 128, 128, 128, 128, 128, - 128, 128, 128, 128, 128, 128, 128, 128, - 128, 128, 128, 128, 128, 128, 128, 128, - 128, 128, 128, 128, 128, 128, 128, 128, - 128, 128, 128, 128, 128, 128, 128, 128, - 128, 128, 128, 128, 128, 128, 128, 128, - 128, 128, 128, 128, 128, 128, 128, 128, - 128, 128, 128, 128, 128, 128, 128, 128, - 128, 128, 128, 128, 128, 128, 128, 128, - 128, 128, 128, 128, 128, 128, 128, 128, - 128, 128, 128, 128, 128, 128, 128, 128, - 128, 128, 128, 128, 128, 128, 128, 128, - 128, 128, 128, 128, 128, 128, 128, 128, - 128, 128, 128, 128, 128, 128, 128, 128, - 128, 128, 128, 128, 128, 128, 128, 128, - 128, 128, 128, 128, 128, 128, 128, 128, - 128, 128, 128, 128, 128, 128, 128, 128, - 128, 128, 128, 128, 128, 128, 128, 128, - }; - if ((m_limit - m_cursor) < 5) - { - yyfill(); // LCOV_EXCL_LINE; - } - yych = *m_cursor; - if (yybm[0 + yych] & 32) - { - goto basic_json_parser_6; - } - if (yych <= '\\') - { - if (yych <= '-') - { - if (yych <= '"') - { - if (yych <= 0x00) - { - goto basic_json_parser_2; - } - if (yych <= '!') - { - goto basic_json_parser_4; - } - goto basic_json_parser_9; - } - else - { - if (yych <= '+') - { - goto basic_json_parser_4; - } - if (yych <= ',') - { - goto basic_json_parser_10; - } - goto basic_json_parser_12; - } - } - else - { - if (yych <= '9') - { - if (yych <= '/') - { - goto basic_json_parser_4; - } - if (yych <= '0') - { - goto basic_json_parser_13; - } - goto basic_json_parser_15; - } - else - { - if (yych <= ':') - { - goto basic_json_parser_17; - } - if (yych == '[') - { - goto basic_json_parser_19; - } - goto basic_json_parser_4; - } - } - } - else - { - if (yych <= 't') - { - if (yych <= 'f') - { - if (yych <= ']') - { - goto basic_json_parser_21; - } - if (yych <= 'e') - { - goto basic_json_parser_4; - } - goto basic_json_parser_23; - } - else - { - if (yych == 'n') - { - goto basic_json_parser_24; - } - if (yych <= 's') - { - goto basic_json_parser_4; - } - goto basic_json_parser_25; - } - } - else - { - if (yych <= '|') - { - if (yych == '{') - { - goto basic_json_parser_26; - } - goto basic_json_parser_4; - } - else - { - if (yych <= '}') - { - goto basic_json_parser_28; - } - if (yych == 0xEF) - { - goto basic_json_parser_30; - } - goto basic_json_parser_4; - } - } - } -basic_json_parser_2: - ++m_cursor; - { - return token_type::end_of_input; - } -basic_json_parser_4: - ++m_cursor; -basic_json_parser_5: - { - return token_type::parse_error; - } -basic_json_parser_6: - ++m_cursor; - if (m_limit <= m_cursor) - { - yyfill(); // LCOV_EXCL_LINE; - } - yych = *m_cursor; - if (yybm[0 + yych] & 32) - { - goto basic_json_parser_6; - } - { - return scan(); - } -basic_json_parser_9: - yyaccept = 0; - yych = *(m_marker = ++m_cursor); - if (yych <= 0x0F) - { - goto basic_json_parser_5; - } - goto basic_json_parser_32; -basic_json_parser_10: - ++m_cursor; - { - return token_type::value_separator; - } -basic_json_parser_12: - yych = *++m_cursor; - if (yych <= '/') - { - goto basic_json_parser_5; - } - if (yych <= '0') - { - goto basic_json_parser_13; - } - if (yych <= '9') - { - goto basic_json_parser_15; - } - goto basic_json_parser_5; -basic_json_parser_13: - yyaccept = 1; - yych = *(m_marker = ++m_cursor); - if (yych <= 'D') - { - if (yych == '.') - { - goto basic_json_parser_37; - } - } - else - { - if (yych <= 'E') - { - goto basic_json_parser_38; - } - if (yych == 'e') - { - goto basic_json_parser_38; - } - } -basic_json_parser_14: - { - return token_type::value_number; - } -basic_json_parser_15: - yyaccept = 1; - m_marker = ++m_cursor; - if ((m_limit - m_cursor) < 3) - { - yyfill(); // LCOV_EXCL_LINE; - } - yych = *m_cursor; - if (yybm[0 + yych] & 64) - { - goto basic_json_parser_15; - } - if (yych <= 'D') - { - if (yych == '.') - { - goto basic_json_parser_37; - } - goto basic_json_parser_14; - } - else - { - if (yych <= 'E') - { - goto basic_json_parser_38; - } - if (yych == 'e') - { - goto basic_json_parser_38; - } - goto basic_json_parser_14; - } -basic_json_parser_17: - ++m_cursor; - { - return token_type::name_separator; - } -basic_json_parser_19: - ++m_cursor; - { - return token_type::begin_array; - } -basic_json_parser_21: - ++m_cursor; - { - return token_type::end_array; - } -basic_json_parser_23: - yyaccept = 0; - yych = *(m_marker = ++m_cursor); - if (yych == 'a') - { - goto basic_json_parser_39; - } - goto basic_json_parser_5; -basic_json_parser_24: - yyaccept = 0; - yych = *(m_marker = ++m_cursor); - if (yych == 'u') - { - goto basic_json_parser_40; - } - goto basic_json_parser_5; -basic_json_parser_25: - yyaccept = 0; - yych = *(m_marker = ++m_cursor); - if (yych == 'r') - { - goto basic_json_parser_41; - } - goto basic_json_parser_5; -basic_json_parser_26: - ++m_cursor; - { - return token_type::begin_object; - } -basic_json_parser_28: - ++m_cursor; - { - return token_type::end_object; - } -basic_json_parser_30: - yyaccept = 0; - yych = *(m_marker = ++m_cursor); - if (yych == 0xBB) - { - goto basic_json_parser_42; - } - goto basic_json_parser_5; -basic_json_parser_31: - ++m_cursor; - if (m_limit <= m_cursor) - { - yyfill(); // LCOV_EXCL_LINE; - } - yych = *m_cursor; -basic_json_parser_32: - if (yybm[0 + yych] & 128) - { - goto basic_json_parser_31; - } - if (yych <= 0x0F) - { - goto basic_json_parser_33; - } - if (yych <= '"') - { - goto basic_json_parser_34; - } - goto basic_json_parser_36; -basic_json_parser_33: - m_cursor = m_marker; - if (yyaccept == 0) - { - goto basic_json_parser_5; - } - else - { - goto basic_json_parser_14; - } -basic_json_parser_34: - ++m_cursor; - { - return token_type::value_string; - } -basic_json_parser_36: - ++m_cursor; - if (m_limit <= m_cursor) - { - yyfill(); // LCOV_EXCL_LINE; - } - yych = *m_cursor; - if (yych <= 'e') - { - if (yych <= '/') - { - if (yych == '"') - { - goto basic_json_parser_31; - } - if (yych <= '.') - { - goto basic_json_parser_33; - } - goto basic_json_parser_31; - } - else - { - if (yych <= '\\') - { - if (yych <= '[') - { - goto basic_json_parser_33; - } - goto basic_json_parser_31; - } - else - { - if (yych == 'b') - { - goto basic_json_parser_31; - } - goto basic_json_parser_33; - } - } - } - else - { - if (yych <= 'q') - { - if (yych <= 'f') - { - goto basic_json_parser_31; - } - if (yych == 'n') - { - goto basic_json_parser_31; - } - goto basic_json_parser_33; - } - else - { - if (yych <= 's') - { - if (yych <= 'r') - { - goto basic_json_parser_31; - } - goto basic_json_parser_33; - } - else - { - if (yych <= 't') - { - goto basic_json_parser_31; - } - if (yych <= 'u') - { - goto basic_json_parser_43; - } - goto basic_json_parser_33; - } - } - } -basic_json_parser_37: - yych = *++m_cursor; - if (yych <= '/') - { - goto basic_json_parser_33; - } - if (yych <= '9') - { - goto basic_json_parser_44; - } - goto basic_json_parser_33; -basic_json_parser_38: - yych = *++m_cursor; - if (yych <= ',') - { - if (yych == '+') - { - goto basic_json_parser_46; - } - goto basic_json_parser_33; - } - else - { - if (yych <= '-') - { - goto basic_json_parser_46; - } - if (yych <= '/') - { - goto basic_json_parser_33; - } - if (yych <= '9') - { - goto basic_json_parser_47; - } - goto basic_json_parser_33; - } -basic_json_parser_39: - yych = *++m_cursor; - if (yych == 'l') - { - goto basic_json_parser_49; - } - goto basic_json_parser_33; -basic_json_parser_40: - yych = *++m_cursor; - if (yych == 'l') - { - goto basic_json_parser_50; - } - goto basic_json_parser_33; -basic_json_parser_41: - yych = *++m_cursor; - if (yych == 'u') - { - goto basic_json_parser_51; - } - goto basic_json_parser_33; -basic_json_parser_42: - yych = *++m_cursor; - if (yych == 0xBF) - { - goto basic_json_parser_52; - } - goto basic_json_parser_33; -basic_json_parser_43: - ++m_cursor; - if (m_limit <= m_cursor) - { - yyfill(); // LCOV_EXCL_LINE; - } - yych = *m_cursor; - if (yych <= '@') - { - if (yych <= '/') - { - goto basic_json_parser_33; - } - if (yych <= '9') - { - goto basic_json_parser_54; - } - goto basic_json_parser_33; - } - else - { - if (yych <= 'F') - { - goto basic_json_parser_54; - } - if (yych <= '`') - { - goto basic_json_parser_33; - } - if (yych <= 'f') - { - goto basic_json_parser_54; - } - goto basic_json_parser_33; - } -basic_json_parser_44: - yyaccept = 1; - m_marker = ++m_cursor; - if ((m_limit - m_cursor) < 3) - { - yyfill(); // LCOV_EXCL_LINE; - } - yych = *m_cursor; - if (yych <= 'D') - { - if (yych <= '/') - { - goto basic_json_parser_14; - } - if (yych <= '9') - { - goto basic_json_parser_44; - } - goto basic_json_parser_14; - } - else - { - if (yych <= 'E') - { - goto basic_json_parser_38; - } - if (yych == 'e') - { - goto basic_json_parser_38; - } - goto basic_json_parser_14; - } -basic_json_parser_46: - yych = *++m_cursor; - if (yych <= '/') - { - goto basic_json_parser_33; - } - if (yych >= ':') - { - goto basic_json_parser_33; - } -basic_json_parser_47: - ++m_cursor; - if (m_limit <= m_cursor) - { - yyfill(); // LCOV_EXCL_LINE; - } - yych = *m_cursor; - if (yych <= '/') - { - goto basic_json_parser_14; - } - if (yych <= '9') - { - goto basic_json_parser_47; - } - goto basic_json_parser_14; -basic_json_parser_49: - yych = *++m_cursor; - if (yych == 's') - { - goto basic_json_parser_55; - } - goto basic_json_parser_33; -basic_json_parser_50: - yych = *++m_cursor; - if (yych == 'l') - { - goto basic_json_parser_56; - } - goto basic_json_parser_33; -basic_json_parser_51: - yych = *++m_cursor; - if (yych == 'e') - { - goto basic_json_parser_58; - } - goto basic_json_parser_33; -basic_json_parser_52: - ++m_cursor; - { - return scan(); - } -basic_json_parser_54: - ++m_cursor; - if (m_limit <= m_cursor) - { - yyfill(); // LCOV_EXCL_LINE; - } - yych = *m_cursor; - if (yych <= '@') - { - if (yych <= '/') - { - goto basic_json_parser_33; - } - if (yych <= '9') - { - goto basic_json_parser_60; - } - goto basic_json_parser_33; - } - else - { - if (yych <= 'F') - { - goto basic_json_parser_60; - } - if (yych <= '`') - { - goto basic_json_parser_33; - } - if (yych <= 'f') - { - goto basic_json_parser_60; - } - goto basic_json_parser_33; - } -basic_json_parser_55: - yych = *++m_cursor; - if (yych == 'e') - { - goto basic_json_parser_61; - } - goto basic_json_parser_33; -basic_json_parser_56: - ++m_cursor; - { - return token_type::literal_null; - } -basic_json_parser_58: - ++m_cursor; - { - return token_type::literal_true; - } -basic_json_parser_60: - ++m_cursor; - if (m_limit <= m_cursor) - { - yyfill(); // LCOV_EXCL_LINE; - } - yych = *m_cursor; - if (yych <= '@') - { - if (yych <= '/') - { - goto basic_json_parser_33; - } - if (yych <= '9') - { - goto basic_json_parser_63; - } - goto basic_json_parser_33; - } - else - { - if (yych <= 'F') - { - goto basic_json_parser_63; - } - if (yych <= '`') - { - goto basic_json_parser_33; - } - if (yych <= 'f') - { - goto basic_json_parser_63; - } - goto basic_json_parser_33; - } -basic_json_parser_61: - ++m_cursor; - { - return token_type::literal_false; - } -basic_json_parser_63: - ++m_cursor; - if (m_limit <= m_cursor) - { - yyfill(); // LCOV_EXCL_LINE; - } - yych = *m_cursor; - if (yych <= '@') - { - if (yych <= '/') - { - goto basic_json_parser_33; - } - if (yych <= '9') - { - goto basic_json_parser_31; - } - goto basic_json_parser_33; - } - else - { - if (yych <= 'F') - { - goto basic_json_parser_31; - } - if (yych <= '`') - { - goto basic_json_parser_33; - } - if (yych <= 'f') - { - goto basic_json_parser_31; - } - goto basic_json_parser_33; - } - } - - } - - /// append data from the stream to the internal buffer - void yyfill() noexcept - { - if (m_stream == nullptr or not * m_stream) - { - return; - } - - const auto offset_start = m_start - m_content; - const auto offset_marker = m_marker - m_start; - const auto offset_cursor = m_cursor - m_start; - - m_buffer.erase(0, static_cast<size_t>(offset_start)); - std::string line; - assert(m_stream != nullptr); - std::getline(*m_stream, line); - m_buffer += "\n" + line; // add line with newline symbol - - m_content = reinterpret_cast<const lexer_char_t*>(m_buffer.c_str()); - assert(m_content != nullptr); - m_start = m_content; - m_marker = m_start + offset_marker; - m_cursor = m_start + offset_cursor; - m_limit = m_start + m_buffer.size() - 1; - } - - /// return string representation of last read token - string_t get_token() const - { - assert(m_start != nullptr); - return string_t(reinterpret_cast<typename string_t::const_pointer>(m_start), - static_cast<size_t>(m_cursor - m_start)); - } - - /*! - @brief return string value for string tokens - - The function iterates the characters between the opening and closing - quotes of the string value. The complete string is the range - [m_start,m_cursor). Consequently, we iterate from m_start+1 to - m_cursor-1. - - We differentiate two cases: - - 1. Escaped characters. In this case, a new character is constructed - according to the nature of the escape. Some escapes create new - characters (e.g., `"\\n"` is replaced by `"\n"`), some are copied - as is (e.g., `"\\\\"`). Furthermore, Unicode escapes of the shape - `"\\uxxxx"` need special care. In this case, to_unicode takes care - of the construction of the values. - 2. Unescaped characters are copied as is. - - @return string value of current token without opening and closing - quotes - @throw std::out_of_range if to_unicode fails - */ - string_t get_string() const - { - string_t result; - result.reserve(static_cast<size_t>(m_cursor - m_start - 2)); - - // iterate the result between the quotes - for (const lexer_char_t* i = m_start + 1; i < m_cursor - 1; ++i) - { - // process escaped characters - if (*i == '\\') - { - // read next character - ++i; - - switch (*i) - { - // the default escapes - case 't': - { - result += "\t"; - break; - } - case 'b': - { - result += "\b"; - break; - } - case 'f': - { - result += "\f"; - break; - } - case 'n': - { - result += "\n"; - break; - } - case 'r': - { - result += "\r"; - break; - } - case '\\': - { - result += "\\"; - break; - } - case '/': - { - result += "/"; - break; - } - case '"': - { - result += "\""; - break; - } - - // unicode - case 'u': - { - // get code xxxx from uxxxx - auto codepoint = std::strtoul(std::string(reinterpret_cast<typename string_t::const_pointer>(i + 1), - 4).c_str(), nullptr, 16); - - // check if codepoint is a high surrogate - if (codepoint >= 0xD800 and codepoint <= 0xDBFF) - { - // make sure there is a subsequent unicode - if ((i + 6 >= m_limit) or * (i + 5) != '\\' or * (i + 6) != 'u') - { - throw std::invalid_argument("missing low surrogate"); - } - - // get code yyyy from uxxxx\uyyyy - auto codepoint2 = std::strtoul(std::string(reinterpret_cast<typename string_t::const_pointer> - (i + 7), 4).c_str(), nullptr, 16); - result += to_unicode(codepoint, codepoint2); - // skip the next 10 characters (xxxx\uyyyy) - i += 10; - } - else - { - // add unicode character(s) - result += to_unicode(codepoint); - // skip the next four characters (xxxx) - i += 4; - } - break; - } - } - } - else - { - // all other characters are just copied to the end of the - // string - result.append(1, static_cast<typename string_t::value_type>(*i)); - } - } - - return result; - } - - /*! - @brief parse floating point number - - This function (and its overloads) serves to select the most approprate - standard floating point number parsing function based on the type - supplied via the first parameter. Set this to @a - static_cast<number_float_t*>(nullptr). - - @param[in] type the @ref number_float_t in use - - @param[in,out] endptr recieves a pointer to the first character after - the number - - @return the floating point number - - @bug This function uses `std::strtof`, `std::strtod`, or `std::strtold` - which use the current C locale to determine which character is used as - decimal point character. This may yield to parse errors if the locale - does not used `.`. - */ - long double str_to_float_t(long double* /* type */, char** endptr) const - { - return std::strtold(reinterpret_cast<typename string_t::const_pointer>(m_start), endptr); - } - - /*! - @brief parse floating point number - - This function (and its overloads) serves to select the most approprate - standard floating point number parsing function based on the type - supplied via the first parameter. Set this to @a - static_cast<number_float_t*>(nullptr). - - @param[in] type the @ref number_float_t in use - - @param[in,out] endptr recieves a pointer to the first character after - the number - - @return the floating point number - */ - double str_to_float_t(double* /* type */, char** endptr) const - { - return std::strtod(reinterpret_cast<typename string_t::const_pointer>(m_start), endptr); - } - - /*! - @brief parse floating point number - - This function (and its overloads) serves to select the most approprate - standard floating point number parsing function based on the type - supplied via the first parameter. Set this to @a - static_cast<number_float_t*>(nullptr). - - @param[in] type the @ref number_float_t in use - - @param[in,out] endptr recieves a pointer to the first character after - the number - - @return the floating point number - */ - float str_to_float_t(float* /* type */, char** endptr) const - { - return std::strtof(reinterpret_cast<typename string_t::const_pointer>(m_start), endptr); - } - - /*! - @brief return number value for number tokens - - This function translates the last token into the most appropriate - number type (either integer, unsigned integer or floating point), - which is passed back to the caller via the result parameter. - - This function parses the integer component up to the radix point or - exponent while collecting information about the 'floating point - representation', which it stores in the result parameter. If there is - no radix point or exponent, and the number can fit into a @ref - number_integer_t or @ref number_unsigned_t then it sets the result - parameter accordingly. - - The 'floating point representation' includes the number of significant - figures after the radix point, whether the number is in exponential or - decimal form, the capitalization of the exponent marker, and if the - optional '+' is present in the exponent. This information is necessary - to perform accurate round trips of floating point numbers. - - If the number is a floating point number the number is then parsed - using @a std:strtod (or @a std:strtof or @a std::strtold). - - @param[out] result @ref basic_json object to receive the number, or - NAN if the conversion read past the current token. The latter case - needs to be treated by the caller function. - */ - void get_number(basic_json& result) const - { - assert(m_start != nullptr); - - const lexer::lexer_char_t* curptr = m_start; - - // remember this number was parsed (for later serialization) - result.m_type.bits.parsed = true; + std::vector<uint8_t> result; + to_msgpack(j, result); + return result; + } - // 'found_radix_point' will be set to 0xFF upon finding a radix - // point and later used to mask in/out the precision depending - // whether a radix is found i.e. 'precision &= found_radix_point' - uint8_t found_radix_point = 0; - uint8_t precision = 0; + static void to_msgpack(const basic_json& j, detail::output_adapter<uint8_t> o) + { + binary_writer<uint8_t>(o).write_msgpack(j); + } + + static void to_msgpack(const basic_json& j, detail::output_adapter<char> o) + { + binary_writer<char>(o).write_msgpack(j); + } + + /*! + @brief create a JSON value from an input in CBOR format + + Deserializes a given input @a i to a JSON value using the CBOR (Concise + Binary Object Representation) serialization format. - // accumulate the integer conversion result (unsigned for now) - number_unsigned_t value = 0; + The library maps CBOR types to JSON value types as follows: - // maximum absolute value of the relevant integer type - number_unsigned_t max; + CBOR type | JSON value type | first byte + ---------------------- | --------------- | ---------- + Integer | number_unsigned | 0x00..0x17 + Unsigned integer | number_unsigned | 0x18 + Unsigned integer | number_unsigned | 0x19 + Unsigned integer | number_unsigned | 0x1A + Unsigned integer | number_unsigned | 0x1B + Negative integer | number_integer | 0x20..0x37 + Negative integer | number_integer | 0x38 + Negative integer | number_integer | 0x39 + Negative integer | number_integer | 0x3A + Negative integer | number_integer | 0x3B + Negative integer | number_integer | 0x40..0x57 + UTF-8 string | string | 0x60..0x77 + UTF-8 string | string | 0x78 + UTF-8 string | string | 0x79 + UTF-8 string | string | 0x7A + UTF-8 string | string | 0x7B + UTF-8 string | string | 0x7F + array | array | 0x80..0x97 + array | array | 0x98 + array | array | 0x99 + array | array | 0x9A + array | array | 0x9B + array | array | 0x9F + map | object | 0xA0..0xB7 + map | object | 0xB8 + map | object | 0xB9 + map | object | 0xBA + map | object | 0xBB + map | object | 0xBF + False | `false` | 0xF4 + True | `true` | 0xF5 + Nill | `null` | 0xF6 + Half-Precision Float | number_float | 0xF9 + Single-Precision Float | number_float | 0xFA + Double-Precision Float | number_float | 0xFB + + @warning The mapping is **incomplete** in the sense that not all CBOR + types can be converted to a JSON value. The following CBOR types + are not supported and will yield parse errors (parse_error.112): + - byte strings (0x40..0x5F) + - date/time (0xC0..0xC1) + - bignum (0xC2..0xC3) + - decimal fraction (0xC4) + - bigfloat (0xC5) + - tagged items (0xC6..0xD4, 0xD8..0xDB) + - expected conversions (0xD5..0xD7) + - simple values (0xE0..0xF3, 0xF8) + - undefined (0xF7) + + @warning CBOR allows map keys of any type, whereas JSON only allows + strings as keys in object values. Therefore, CBOR maps with keys + other than UTF-8 strings are rejected (parse_error.113). + + @note Any CBOR output created @ref to_cbor can be successfully parsed by + @ref from_cbor. + + @param[in] i an input in CBOR format convertible to an input adapter + @param[in] strict whether to expect the input to be consumed until EOF + (true by default) + @return deserialized JSON value + + @throw parse_error.110 if the given input ends prematurely or the end of + file was not reached when @a strict was set to true + @throw parse_error.112 if unsupported features from CBOR were + used in the given input @a v or if the input is not valid CBOR + @throw parse_error.113 if a string was expected as map key, but not found + + @complexity Linear in the size of the input @a i. + + @liveexample{The example shows the deserialization of a byte vector in CBOR + format to a JSON value.,from_cbor} + + @sa http://cbor.io + @sa @ref to_cbor(const basic_json&) for the analogous serialization + @sa @ref from_msgpack(detail::input_adapter, const bool) for the + related MessagePack format + + @since version 2.0.9; parameter @a start_index since 2.1.1; changed to + consume input adapters, removed start_index parameter, and added + @a strict parameter since 3.0.0 + */ + static basic_json from_cbor(detail::input_adapter i, + const bool strict = true) + { + return binary_reader(i).parse_cbor(strict); + } + + /*! + @copydoc from_cbor(detail::input_adapter, const bool) + */ + template<typename A1, typename A2, + detail::enable_if_t<std::is_constructible<detail::input_adapter, A1, A2>::value, int> = 0> + static basic_json from_cbor(A1 && a1, A2 && a2, const bool strict = true) + { + return binary_reader(detail::input_adapter(std::forward<A1>(a1), std::forward<A2>(a2))).parse_cbor(strict); + } + + /*! + @brief create a JSON value from an input in MessagePack format + + Deserializes a given input @a i to a JSON value using the MessagePack + serialization format. + + The library maps MessagePack types to JSON value types as follows: + + MessagePack type | JSON value type | first byte + ---------------- | --------------- | ---------- + positive fixint | number_unsigned | 0x00..0x7F + fixmap | object | 0x80..0x8F + fixarray | array | 0x90..0x9F + fixstr | string | 0xA0..0xBF + nil | `null` | 0xC0 + false | `false` | 0xC2 + true | `true` | 0xC3 + float 32 | number_float | 0xCA + float 64 | number_float | 0xCB + uint 8 | number_unsigned | 0xCC + uint 16 | number_unsigned | 0xCD + uint 32 | number_unsigned | 0xCE + uint 64 | number_unsigned | 0xCF + int 8 | number_integer | 0xD0 + int 16 | number_integer | 0xD1 + int 32 | number_integer | 0xD2 + int 64 | number_integer | 0xD3 + str 8 | string | 0xD9 + str 16 | string | 0xDA + str 32 | string | 0xDB + array 16 | array | 0xDC + array 32 | array | 0xDD + map 16 | object | 0xDE + map 32 | object | 0xDF + negative fixint | number_integer | 0xE0-0xFF - // temporarily store the type to avoid unecessary bitfield access - value_t type; + @warning The mapping is **incomplete** in the sense that not all + MessagePack types can be converted to a JSON value. The following + MessagePack types are not supported and will yield parse errors: + - bin 8 - bin 32 (0xC4..0xC6) + - ext 8 - ext 32 (0xC7..0xC9) + - fixext 1 - fixext 16 (0xD4..0xD8) - // look for sign - if (*curptr == '-') - { - type = value_t::number_integer; - max = static_cast<uint64_t>((std::numeric_limits<number_integer_t>::max)()) + 1; - curptr++; - } - else - { - type = value_t::number_unsigned; - max = static_cast<uint64_t>((std::numeric_limits<number_unsigned_t>::max)()); - } + @note Any MessagePack output created @ref to_msgpack can be successfully + parsed by @ref from_msgpack. - // count the significant figures - for (; curptr < m_cursor; curptr++) - { - // quickly skip tests if a digit - if (*curptr < '0' || *curptr > '9') - { - if (*curptr == '.') - { - // don't count '.' but change to float - type = value_t::number_float; + @param[in] i an input in MessagePack format convertible to an input + adapter + @param[in] strict whether to expect the input to be consumed until EOF + (true by default) - // reset precision count - precision = 0; - found_radix_point = 0xFF; - continue; - } - // assume exponent (if not then will fail parse): change to - // float, stop counting and record exponent details - type = value_t::number_float; - result.m_type.bits.has_exp = true; + @throw parse_error.110 if the given input ends prematurely or the end of + file was not reached when @a strict was set to true + @throw parse_error.112 if unsupported features from MessagePack were + used in the given input @a i or if the input is not valid MessagePack + @throw parse_error.113 if a string was expected as map key, but not found - // exponent capitalization - result.m_type.bits.exp_cap = (*curptr == 'E'); + @complexity Linear in the size of the input @a i. - // exponent '+' sign - result.m_type.bits.exp_plus = (*(++curptr) == '+'); - break; - } + @liveexample{The example shows the deserialization of a byte vector in + MessagePack format to a JSON value.,from_msgpack} - // skip if definitely not an integer - if (type != value_t::number_float) - { - // multiply last value by ten and add the new digit - auto temp = value * 10 + *curptr - 0x30; + @sa http://msgpack.org + @sa @ref to_msgpack(const basic_json&) for the analogous serialization + @sa @ref from_cbor(detail::input_adapter, const bool) for the related CBOR + format - // test for overflow - if (temp < value || temp > max) - { - // overflow - type = value_t::number_float; - } - else - { - // no overflow - save it - value = temp; - } - } - ++precision; - } - - // If no radix point was found then precision would now be set to - // the number of digits, which is wrong - clear it. - result.m_type.bits.precision = precision & found_radix_point; - - // save the value (if not a float) - if (type == value_t::number_unsigned) - { - result.m_value.number_unsigned = value; - } - else if (type == value_t::number_integer) - { - result.m_value.number_integer = -static_cast<number_integer_t>(value); - } - else - { - // parse with strtod - result.m_value.number_float = str_to_float_t(static_cast<number_float_t*>(nullptr), NULL); - } - - // save the type - result.m_type = type; - } - - private: - /// optional input stream - std::istream* m_stream = nullptr; - /// the buffer - string_t m_buffer; - /// the buffer pointer - const lexer_char_t* m_content = nullptr; - /// pointer to the beginning of the current symbol - const lexer_char_t* m_start = nullptr; - /// pointer for backtracking information - const lexer_char_t* m_marker = nullptr; - /// pointer to the current symbol - const lexer_char_t* m_cursor = nullptr; - /// pointer to the end of the buffer - const lexer_char_t* m_limit = nullptr; - }; - - /*! - @brief syntax analysis - - This class implements a recursive decent parser. + @since version 2.0.9; parameter @a start_index since 2.1.1; changed to + consume input adapters, removed start_index parameter, and added + @a strict parameter since 3.0.0 */ - class parser + static basic_json from_msgpack(detail::input_adapter i, + const bool strict = true) { - public: - /// constructor for strings - parser(const string_t& s, parser_callback_t cb = nullptr) noexcept - : callback(cb), m_lexer(s) - { - // read first token - get_token(); - } - - /// a parser reading from an input stream - parser(std::istream& _is, parser_callback_t cb = nullptr) noexcept - : callback(cb), m_lexer(&_is) - { - // read first token - get_token(); - } - - /// public parser interface - basic_json parse() - { - basic_json result = parse_internal(true); - - expect(lexer::token_type::end_of_input); - - // return parser result and replace it with null in case the - // top-level value was discarded by the callback function - return result.is_discarded() ? basic_json() : result; - } - - private: - /// the actual parser - basic_json parse_internal(bool keep) - { - auto result = basic_json(value_t::discarded); - - switch (last_token) - { - case lexer::token_type::begin_object: - { - if (keep and (not callback or (keep = callback(depth++, parse_event_t::object_start, result)))) - { - // explicitly set result to object to cope with {} - result.m_type = value_t::object; - result.m_value = json_value(value_t::object); - } - - // read next token - get_token(); - - // closing } -> we are done - if (last_token == lexer::token_type::end_object) - { - get_token(); - if (keep and callback and not callback(--depth, parse_event_t::object_end, result)) - { - result = basic_json(value_t::discarded); - } - return result; - } - - // no comma is expected here - unexpect(lexer::token_type::value_separator); - - // otherwise: parse key-value pairs - do - { - // ugly, but could be fixed with loop reorganization - if (last_token == lexer::token_type::value_separator) - { - get_token(); - } - - // store key - expect(lexer::token_type::value_string); - const auto key = m_lexer.get_string(); - - bool keep_tag = false; - if (keep) - { - if (callback) - { - basic_json k(key); - keep_tag = callback(depth, parse_event_t::key, k); - } - else - { - keep_tag = true; - } - } - - // parse separator (:) - get_token(); - expect(lexer::token_type::name_separator); - - // parse and add value - get_token(); - auto value = parse_internal(keep); - if (keep and keep_tag and not value.is_discarded()) - { - result[key] = std::move(value); - } - } - while (last_token == lexer::token_type::value_separator); - - // closing } - expect(lexer::token_type::end_object); - get_token(); - if (keep and callback and not callback(--depth, parse_event_t::object_end, result)) - { - result = basic_json(value_t::discarded); - } - - return result; - } - - case lexer::token_type::begin_array: - { - if (keep and (not callback or (keep = callback(depth++, parse_event_t::array_start, result)))) - { - // explicitly set result to object to cope with [] - result.m_type = value_t::array; - result.m_value = json_value(value_t::array); - } - - // read next token - get_token(); - - // closing ] -> we are done - if (last_token == lexer::token_type::end_array) - { - get_token(); - if (callback and not callback(--depth, parse_event_t::array_end, result)) - { - result = basic_json(value_t::discarded); - } - return result; - } - - // no comma is expected here - unexpect(lexer::token_type::value_separator); - - // otherwise: parse values - do - { - // ugly, but could be fixed with loop reorganization - if (last_token == lexer::token_type::value_separator) - { - get_token(); - } - - // parse value - auto value = parse_internal(keep); - if (keep and not value.is_discarded()) - { - result.push_back(std::move(value)); - } - } - while (last_token == lexer::token_type::value_separator); - - // closing ] - expect(lexer::token_type::end_array); - get_token(); - if (keep and callback and not callback(--depth, parse_event_t::array_end, result)) - { - result = basic_json(value_t::discarded); - } - - return result; - } - - case lexer::token_type::literal_null: - { - get_token(); - result.m_type = value_t::null; - break; - } - - case lexer::token_type::value_string: - { - const auto s = m_lexer.get_string(); - get_token(); - result = basic_json(s); - break; - } - - case lexer::token_type::literal_true: - { - get_token(); - result.m_type = value_t::boolean; - result.m_value = true; - break; - } - - case lexer::token_type::literal_false: - { - get_token(); - result.m_type = value_t::boolean; - result.m_value = false; - break; - } - - case lexer::token_type::value_number: - { - m_lexer.get_number(result); - get_token(); - break; - } - - default: - { - // the last token was unexpected - unexpect(last_token); - } - } - - if (keep and callback and not callback(depth, parse_event_t::value, result)) - { - result = basic_json(value_t::discarded); - } - return result; - } - - /// get next token from lexer - typename lexer::token_type get_token() noexcept - { - last_token = m_lexer.scan(); - return last_token; - } - - void expect(typename lexer::token_type t) const - { - if (t != last_token) - { - std::string error_msg = "parse error - unexpected "; - error_msg += (last_token == lexer::token_type::parse_error ? ("'" + m_lexer.get_token() + "'") : - lexer::token_type_name(last_token)); - error_msg += "; expected " + lexer::token_type_name(t); - throw std::invalid_argument(error_msg); - } - } - - void unexpect(typename lexer::token_type t) const - { - if (t == last_token) - { - std::string error_msg = "parse error - unexpected "; - error_msg += (last_token == lexer::token_type::parse_error ? ("'" + m_lexer.get_token() + "'") : - lexer::token_type_name(last_token)); - throw std::invalid_argument(error_msg); - } - } - - private: - /// current level of recursion - int depth = 0; - /// callback function - parser_callback_t callback; - /// the type of the last read token - typename lexer::token_type last_token = lexer::token_type::uninitialized; - /// the lexer - lexer m_lexer; - }; + return binary_reader(i).parse_msgpack(strict); + } - public: /*! - @brief JSON Pointer - - A JSON pointer defines a string syntax for identifying a specific value - within a JSON document. It can be used with functions `at` and - `operator[]`. Furthermore, JSON pointers are the base for JSON patches. - - @sa [RFC 6901](https://tools.ietf.org/html/rfc6901) - - @since version 2.0.0 + @copydoc from_msgpack(detail::input_adapter, const bool) */ - class json_pointer + template<typename A1, typename A2, + detail::enable_if_t<std::is_constructible<detail::input_adapter, A1, A2>::value, int> = 0> + static basic_json from_msgpack(A1 && a1, A2 && a2, const bool strict = true) { - /// allow basic_json to access private members - friend class basic_json; - - public: - /*! - @brief create JSON pointer - - Create a JSON pointer according to the syntax described in - [Section 3 of RFC6901](https://tools.ietf.org/html/rfc6901#section-3). - - @param[in] s string representing the JSON pointer; if omitted, the - empty string is assumed which references the whole JSON - value - - @throw std::domain_error if reference token is nonempty and does not - begin with a slash (`/`); example: `"JSON pointer must be empty or - begin with /"` - @throw std::domain_error if a tilde (`~`) is not followed by `0` - (representing `~`) or `1` (representing `/`); example: `"escape error: - ~ must be followed with 0 or 1"` - - @liveexample{The example shows the construction several valid JSON - pointers as well as the exceptional behavior.,json_pointer} - - @since version 2.0.0 - */ - explicit json_pointer(const std::string& s = "") - : reference_tokens(split(s)) - {} - - /*! - @brief return a string representation of the JSON pointer - - @invariant For each JSON pointer `ptr`, it holds: - @code {.cpp} - ptr == json_pointer(ptr.to_string()); - @endcode - - @return a string representation of the JSON pointer - - @liveexample{The example shows the result of `to_string`., - json_pointer__to_string} - - @since version 2.0.0 - */ - std::string to_string() const noexcept - { - std::string result; - - for (const auto& reference_token : reference_tokens) - { - result += "/" + escape(reference_token); - } - - return result; - } - - /// @copydoc to_string() - operator std::string() const - { - return to_string(); - } - - private: - /// remove and return last reference pointer - std::string pop_back() - { - if (is_root()) - { - throw std::domain_error("JSON pointer has no parent"); - } - - auto last = reference_tokens.back(); - reference_tokens.pop_back(); - return last; - } - - /// return whether pointer points to the root document - bool is_root() const - { - return reference_tokens.empty(); - } - - json_pointer top() const - { - if (is_root()) - { - throw std::domain_error("JSON pointer has no parent"); - } - - json_pointer result = *this; - result.reference_tokens = {reference_tokens[0]}; - return result; - } - - /*! - @brief create and return a reference to the pointed to value - */ - reference get_and_create(reference j) const - { - pointer result = &j; - - // in case no reference tokens exist, return a reference to the - // JSON value j which will be overwritten by a primitive value - for (const auto& reference_token : reference_tokens) - { - switch (result->m_type) - { - case value_t::null: - { - if (reference_token == "0") - { - // start a new array if reference token is 0 - result = &result->operator[](0); - } - else - { - // start a new object otherwise - result = &result->operator[](reference_token); - } - break; - } - - case value_t::object: - { - // create an entry in the object - result = &result->operator[](reference_token); - break; - } - - case value_t::array: - { - // create an entry in the array - result = &result->operator[](static_cast<size_type>(std::stoi(reference_token))); - break; - } - - /* - The following code is only reached if there exists a - reference token _and_ the current value is primitive. In - this case, we have an error situation, because primitive - values may only occur as single value; that is, with an - empty list of reference tokens. - */ - default: - { - throw std::domain_error("invalid value to unflatten"); - } - } - } - - return *result; - } - - /*! - @brief return a reference to the pointed to value - - @param[in] ptr a JSON value - - @return reference to the JSON value pointed to by the JSON pointer - - @complexity Linear in the length of the JSON pointer. - - @throw std::out_of_range if the JSON pointer can not be resolved - @throw std::domain_error if an array index begins with '0' - @throw std::invalid_argument if an array index was not a number - */ - reference get_unchecked(pointer ptr) const - { - for (const auto& reference_token : reference_tokens) - { - switch (ptr->m_type) - { - case value_t::object: - { - // use unchecked object access - ptr = &ptr->operator[](reference_token); - break; - } - - case value_t::array: - { - // error condition (cf. RFC 6901, Sect. 4) - if (reference_token.size() > 1 and reference_token[0] == '0') - { - throw std::domain_error("array index must not begin with '0'"); - } - - if (reference_token == "-") - { - // explicityly treat "-" as index beyond the end - ptr = &ptr->operator[](ptr->m_value.array->size()); - } - else - { - // convert array index to number; unchecked access - ptr = &ptr->operator[](static_cast<size_type>(std::stoi(reference_token))); - } - break; - } - - default: - { - throw std::out_of_range("unresolved reference token '" + reference_token + "'"); - } - } - } - - return *ptr; - } - - reference get_checked(pointer ptr) const - { - for (const auto& reference_token : reference_tokens) - { - switch (ptr->m_type) - { - case value_t::object: - { - // note: at performs range check - ptr = &ptr->at(reference_token); - break; - } - - case value_t::array: - { - if (reference_token == "-") - { - // "-" always fails the range check - throw std::out_of_range("array index '-' (" + - std::to_string(ptr->m_value.array->size()) + - ") is out of range"); - } - - // error condition (cf. RFC 6901, Sect. 4) - if (reference_token.size() > 1 and reference_token[0] == '0') - { - throw std::domain_error("array index must not begin with '0'"); - } - - // note: at performs range check - ptr = &ptr->at(static_cast<size_type>(std::stoi(reference_token))); - break; - } - - default: - { - throw std::out_of_range("unresolved reference token '" + reference_token + "'"); - } - } - } - - return *ptr; - } - - /*! - @brief return a const reference to the pointed to value - - @param[in] ptr a JSON value - - @return const reference to the JSON value pointed to by the JSON - pointer - */ - const_reference get_unchecked(const_pointer ptr) const - { - for (const auto& reference_token : reference_tokens) - { - switch (ptr->m_type) - { - case value_t::object: - { - // use unchecked object access - ptr = &ptr->operator[](reference_token); - break; - } - - case value_t::array: - { - if (reference_token == "-") - { - // "-" cannot be used for const access - throw std::out_of_range("array index '-' (" + - std::to_string(ptr->m_value.array->size()) + - ") is out of range"); - } - - // error condition (cf. RFC 6901, Sect. 4) - if (reference_token.size() > 1 and reference_token[0] == '0') - { - throw std::domain_error("array index must not begin with '0'"); - } - - // use unchecked array access - ptr = &ptr->operator[](static_cast<size_type>(std::stoi(reference_token))); - break; - } - - default: - { - throw std::out_of_range("unresolved reference token '" + reference_token + "'"); - } - } - } - - return *ptr; - } - - const_reference get_checked(const_pointer ptr) const - { - for (const auto& reference_token : reference_tokens) - { - switch (ptr->m_type) - { - case value_t::object: - { - // note: at performs range check - ptr = &ptr->at(reference_token); - break; - } - - case value_t::array: - { - if (reference_token == "-") - { - // "-" always fails the range check - throw std::out_of_range("array index '-' (" + - std::to_string(ptr->m_value.array->size()) + - ") is out of range"); - } - - // error condition (cf. RFC 6901, Sect. 4) - if (reference_token.size() > 1 and reference_token[0] == '0') - { - throw std::domain_error("array index must not begin with '0'"); - } - - // note: at performs range check - ptr = &ptr->at(static_cast<size_type>(std::stoi(reference_token))); - break; - } - - default: - { - throw std::out_of_range("unresolved reference token '" + reference_token + "'"); - } - } - } - - return *ptr; - } - - /// split the string input to reference tokens - static std::vector<std::string> split(std::string reference_string) - { - std::vector<std::string> result; - - // special case: empty reference string -> no reference tokens - if (reference_string.empty()) - { - return result; - } - - // check if nonempty reference string begins with slash - if (reference_string[0] != '/') - { - throw std::domain_error("JSON pointer must be empty or begin with '/'"); - } - - // extract the reference tokens: - // - slash: position of the last read slash (or end of string) - // - start: position after the previous slash - for ( - // search for the first slash after the first character - size_t slash = reference_string.find_first_of("/", 1), - // set the beginning of the first reference token - start = 1; - // we can stop if start == string::npos+1 = 0 - start != 0; - // set the beginning of the next reference token - // (will eventually be 0 if slash == std::string::npos) - start = slash + 1, - // find next slash - slash = reference_string.find_first_of("/", start)) - { - // use the text between the beginning of the reference token - // (start) and the last slash (slash). - auto reference_token = reference_string.substr(start, slash - start); - - // check reference tokens are properly escaped - for (size_t pos = reference_token.find_first_of("~"); - pos != std::string::npos; - pos = reference_token.find_first_of("~", pos + 1)) - { - assert(reference_token[pos] == '~'); - - // ~ must be followed by 0 or 1 - if (pos == reference_token.size() - 1 or - (reference_token[pos + 1] != '0' and - reference_token[pos + 1] != '1')) - { - throw std::domain_error("escape error: '~' must be followed with '0' or '1'"); - } - } - - // finally, store the reference token - unescape(reference_token); - result.push_back(reference_token); - } - - return result; - } - - private: - /*! - @brief replace all occurrences of a substring by another string - - @param[in,out] s the string to manipulate - @param[in] f the substring to replace with @a t - @param[out] t the string to replace @a f - - @return The string @a s where all occurrences of @a f are replaced - with @a t. - - @pre The search string @a f must not be empty. - - @since version 2.0.0 - */ - static void replace_substring(std::string& s, - const std::string& f, - const std::string& t) - { - assert(not f.empty()); - - for ( - size_t pos = s.find(f); // find first occurrence of f - pos != std::string::npos; // make sure f was found - s.replace(pos, f.size(), t), // replace with t - pos = s.find(f, pos + t.size()) // find next occurrence of f - ); - } - - /// escape tilde and slash - static std::string escape(std::string s) - { - // escape "~"" to "~0" and "/" to "~1" - replace_substring(s, "~", "~0"); - replace_substring(s, "/", "~1"); - return s; - } - - /// unescape tilde and slash - static void unescape(std::string& s) - { - // first transform any occurrence of the sequence '~1' to '/' - replace_substring(s, "~1", "/"); - // then transform any occurrence of the sequence '~0' to '~' - replace_substring(s, "~0", "~"); - } - - /*! - @param[in] reference_string the reference string to the current value - @param[in] value the value to consider - @param[in,out] result the result object to insert values to - - @note Empty objects or arrays are flattened to `null`. - */ - static void flatten(const std::string& reference_string, - const basic_json& value, - basic_json& result) - { - switch (value.m_type) - { - case value_t::array: - { - if (value.m_value.array->empty()) - { - // flatten empty array as null - result[reference_string] = nullptr; - } - else - { - // iterate array and use index as reference string - for (size_t i = 0; i < value.m_value.array->size(); ++i) - { - flatten(reference_string + "/" + std::to_string(i), - value.m_value.array->operator[](i), result); - } - } - break; - } - - case value_t::object: - { - if (value.m_value.object->empty()) - { - // flatten empty object as null - result[reference_string] = nullptr; - } - else - { - // iterate object and use keys as reference string - for (const auto& element : *value.m_value.object) - { - flatten(reference_string + "/" + escape(element.first), - element.second, result); - } - } - break; - } - - default: - { - // add primitive value with its reference string - result[reference_string] = value; - break; - } - } - } - - /*! - @param[in] value flattened JSON - - @return unflattened JSON - */ - static basic_json unflatten(const basic_json& value) - { - if (not value.is_object()) - { - throw std::domain_error("only objects can be unflattened"); - } - - basic_json result; - - // iterate the JSON object values - for (const auto& element : *value.m_value.object) - { - if (not element.second.is_primitive()) - { - throw std::domain_error("values in object must be primitive"); - } - - // assign value to reference pointed to by JSON pointer; Note - // that if the JSON pointer is "" (i.e., points to the whole - // value), function get_and_create returns a reference to - // result itself. An assignment will then create a primitive - // value. - json_pointer(element.first).get_and_create(result) = element.second; - } - - return result; - } + return binary_reader(detail::input_adapter(std::forward<A1>(a1), std::forward<A2>(a2))).parse_msgpack(strict); + } - private: - /// the reference tokens - std::vector<std::string> reference_tokens {}; - }; + /// @} ////////////////////////// // JSON Pointer support // @@ -9470,9 +13677,9 @@ basic_json_parser_63: @complexity Constant. - @throw std::out_of_range if the JSON pointer can not be resolved - @throw std::domain_error if an array index begins with '0' - @throw std::invalid_argument if an array index was not a number + @throw parse_error.106 if an array index begins with '0' + @throw parse_error.109 if an array index was not a number + @throw out_of_range.404 if the JSON pointer can not be resolved @liveexample{The behavior is shown in the example.,operatorjson_pointer} @@ -9497,9 +13704,10 @@ basic_json_parser_63: @complexity Constant. - @throw std::out_of_range if the JSON pointer can not be resolved - @throw std::domain_error if an array index begins with '0' - @throw std::invalid_argument if an array index was not a number + @throw parse_error.106 if an array index begins with '0' + @throw parse_error.109 if an array index was not a number + @throw out_of_range.402 if the array index '-' is used + @throw out_of_range.404 if the JSON pointer can not be resolved @liveexample{The behavior is shown in the example.,operatorjson_pointer_const} @@ -9520,15 +13728,33 @@ basic_json_parser_63: @return reference to the element pointed to by @a ptr - @complexity Constant. + @throw parse_error.106 if an array index in the passed JSON pointer @a ptr + begins with '0'. See example below. - @throw std::out_of_range if the JSON pointer can not be resolved - @throw std::domain_error if an array index begins with '0' - @throw std::invalid_argument if an array index was not a number + @throw parse_error.109 if an array index in the passed JSON pointer @a ptr + is not a number. See example below. - @liveexample{The behavior is shown in the example.,at_json_pointer} + @throw out_of_range.401 if an array index in the passed JSON pointer @a ptr + is out of range. See example below. + + @throw out_of_range.402 if the array index '-' is used in the passed JSON + pointer @a ptr. As `at` provides checked access (and no elements are + implicitly inserted), the index '-' is always invalid. See example below. + + @throw out_of_range.403 if the JSON pointer describes a key of an object + which cannot be found. See example below. + + @throw out_of_range.404 if the JSON pointer @a ptr can not be resolved. + See example below. + + @exceptionsafety Strong guarantee: if an exception is thrown, there are no + changes in the JSON value. + + @complexity Constant. @since version 2.0.0 + + @liveexample{The behavior is shown in the example.,at_json_pointer} */ reference at(const json_pointer& ptr) { @@ -9545,15 +13771,33 @@ basic_json_parser_63: @return reference to the element pointed to by @a ptr - @complexity Constant. + @throw parse_error.106 if an array index in the passed JSON pointer @a ptr + begins with '0'. See example below. - @throw std::out_of_range if the JSON pointer can not be resolved - @throw std::domain_error if an array index begins with '0' - @throw std::invalid_argument if an array index was not a number + @throw parse_error.109 if an array index in the passed JSON pointer @a ptr + is not a number. See example below. - @liveexample{The behavior is shown in the example.,at_json_pointer_const} + @throw out_of_range.401 if an array index in the passed JSON pointer @a ptr + is out of range. See example below. + + @throw out_of_range.402 if the array index '-' is used in the passed JSON + pointer @a ptr. As `at` provides checked access (and no elements are + implicitly inserted), the index '-' is always invalid. See example below. + + @throw out_of_range.403 if the JSON pointer describes a key of an object + which cannot be found. See example below. + + @throw out_of_range.404 if the JSON pointer @a ptr can not be resolved. + See example below. + + @exceptionsafety Strong guarantee: if an exception is thrown, there are no + changes in the JSON value. + + @complexity Constant. @since version 2.0.0 + + @liveexample{The behavior is shown in the example.,at_json_pointer_const} */ const_reference at(const json_pointer& ptr) const { @@ -9568,7 +13812,7 @@ basic_json_parser_63: primitive. The original JSON value can be restored using the @ref unflatten() function. - @return an object that maps JSON pointers to primitve values + @return an object that maps JSON pointers to primitive values @note Empty objects and arrays are flattened to `null` and will not be reconstructed correctly by the @ref unflatten() function. @@ -9609,6 +13853,9 @@ basic_json_parser_63: @complexity Linear in the size the JSON value. + @throw type_error.314 if value is not an object + @throw type_error.315 if object values are not primitive + @liveexample{The following code shows how a flattened JSON object is unflattened into the original nested JSON object.,unflatten} @@ -9635,7 +13882,7 @@ basic_json_parser_63: [JSON Patch](http://jsonpatch.com) defines a JSON document structure for expressing a sequence of operations to apply to a JSON) document. With - this funcion, a JSON Patch is applied to the current JSON value by + this function, a JSON Patch is applied to the current JSON value by executing all operations from the patch. @param[in] json_patch JSON patch document @@ -9646,12 +13893,23 @@ basic_json_parser_63: any case, the original value is not changed: the patch is applied to a copy of the value. - @throw std::out_of_range if a JSON pointer inside the patch could not - be resolved successfully in the current JSON value; example: `"key baz - not found"` - @throw invalid_argument if the JSON patch is malformed (e.g., mandatory + @throw parse_error.104 if the JSON patch does not consist of an array of + objects + + @throw parse_error.105 if the JSON patch is malformed (e.g., mandatory attributes are missing); example: `"operation add must have member path"` + @throw out_of_range.401 if an array index is out of range. + + @throw out_of_range.403 if a JSON pointer inside the patch could not be + resolved successfully in the current JSON value; example: `"key baz not + found"` + + @throw out_of_range.405 if JSON pointer has no parent ("add", "remove", + "move") + + @throw other_error.501 if "test" operation was unsuccessful + @complexity Linear in the size of the JSON value and the length of the JSON patch. As usually only a fraction of the JSON value is affected by the patch, the complexity can usually be neglected. @@ -9674,7 +13932,7 @@ basic_json_parser_63: // the valid JSON Patch operations enum class patch_operations {add, remove, replace, move, copy, test, invalid}; - const auto get_op = [](const std::string op) + const auto get_op = [](const std::string & op) { if (op == "add") { @@ -9718,7 +13976,7 @@ basic_json_parser_63: json_pointer top_pointer = ptr.top(); if (top_pointer != ptr) { - basic_json& x = result.at(top_pointer); + result.at(top_pointer); } // get reference to parent of JSON pointer ptr @@ -9744,11 +14002,11 @@ basic_json_parser_63: } else { - const auto idx = std::stoi(last_path); - if (static_cast<size_type>(idx) > parent.size()) + const auto idx = json_pointer::array_index(last_path); + if (JSON_UNLIKELY(static_cast<size_type>(idx) > parent.size())) { // avoid undefined behavior - throw std::out_of_range("array index " + std::to_string(idx) + " is out of range"); + JSON_THROW(out_of_range::create(401, "array index " + std::to_string(idx) + " is out of range")); } else { @@ -9780,30 +14038,29 @@ basic_json_parser_63: { // perform range check auto it = parent.find(last_path); - if (it != parent.end()) + if (JSON_LIKELY(it != parent.end())) { parent.erase(it); } else { - throw std::out_of_range("key '" + last_path + "' not found"); + JSON_THROW(out_of_range::create(403, "key '" + last_path + "' not found")); } } else if (parent.is_array()) { // note erase performs range check - parent.erase(static_cast<size_type>(std::stoi(last_path))); + parent.erase(static_cast<size_type>(json_pointer::array_index(last_path))); } }; - // type check - if (not json_patch.is_array()) + // type check: top level value must be an array + if (JSON_UNLIKELY(not json_patch.is_array())) { - // a JSON patch must be an array of objects - throw std::invalid_argument("JSON patch must be an array of objects"); + JSON_THROW(parse_error::create(104, 0, "JSON patch must be an array of objects")); } - // iterate and apply th eoperations + // iterate and apply the operations for (const auto& val : json_patch) { // wrapper to get a value for an operation @@ -9818,25 +14075,25 @@ basic_json_parser_63: const auto error_msg = (op == "op") ? "operation" : "operation '" + op + "'"; // check if desired value is present - if (it == val.m_value.object->end()) + if (JSON_UNLIKELY(it == val.m_value.object->end())) { - throw std::invalid_argument(error_msg + " must have member '" + member + "'"); + JSON_THROW(parse_error::create(105, 0, error_msg + " must have member '" + member + "'")); } // check if result is of type string - if (string_type and not it->second.is_string()) + if (JSON_UNLIKELY(string_type and not it->second.is_string())) { - throw std::invalid_argument(error_msg + " must have string member '" + member + "'"); + JSON_THROW(parse_error::create(105, 0, error_msg + " must have string member '" + member + "'")); } // no error: return value return it->second; }; - // type check - if (not val.is_object()) + // type check: every element of the array must be an object + if (JSON_UNLIKELY(not val.is_object())) { - throw std::invalid_argument("JSON patch must be an array of objects"); + JSON_THROW(parse_error::create(104, 0, "JSON patch must be an array of objects")); } // collect mandatory members @@ -9884,32 +14141,37 @@ basic_json_parser_63: case patch_operations::copy: { - const std::string from_path = get_value("copy", "from", true);; + const std::string from_path = get_value("copy", "from", true); const json_pointer from_ptr(from_path); // the "from" location must exist - use at() - result[ptr] = result.at(from_ptr); + basic_json v = result.at(from_ptr); + + // The copy is functionally identical to an "add" + // operation at the target location using the value + // specified in the "from" member. + operation_add(ptr, v); break; } case patch_operations::test: { bool success = false; - try + JSON_TRY { // check if "value" matches the one at "path" // the "path" location must exist - use at() success = (result.at(ptr) == get_value("test", "value", false)); } - catch (std::out_of_range&) + JSON_CATCH (out_of_range&) { // ignore out of range errors: success remains false } // throw an exception if test fails - if (not success) + if (JSON_UNLIKELY(not success)) { - throw std::domain_error("unsuccessful: " + val.dump()); + JSON_THROW(other_error::create(501, "unsuccessful: " + val.dump())); } break; @@ -9919,7 +14181,7 @@ basic_json_parser_63: { // op must be "add", "remove", "replace", "move", "copy", or // "test" - throw std::invalid_argument("operation value '" + op + "' is invalid"); + JSON_THROW(parse_error::create(105, 0, "operation value '" + op + "' is invalid")); } } } @@ -9942,8 +14204,8 @@ basic_json_parser_63: @note Currently, only `remove`, `add`, and `replace` operations are generated. - @param[in] source JSON value to copare from - @param[in] target JSON value to copare against + @param[in] source JSON value to compare from + @param[in] target JSON value to compare against @param[in] path helper value to create JSON pointers @return a JSON patch to convert the @a source to @a target @@ -9959,9 +14221,8 @@ basic_json_parser_63: @since version 2.0.0 */ - static basic_json diff(const basic_json& source, - const basic_json& target, - std::string path = "") + static basic_json diff(const basic_json& source, const basic_json& target, + const std::string& path = "") { // the patch basic_json result(value_t::array); @@ -9977,9 +14238,7 @@ basic_json_parser_63: // different types: replace value result.push_back( { - {"op", "replace"}, - {"path", path}, - {"value", target} + {"op", "replace"}, {"path", path}, {"value", target} }); } else @@ -9989,7 +14248,7 @@ basic_json_parser_63: case value_t::array: { // first pass: traverse common elements - size_t i = 0; + std::size_t i = 0; while (i < source.size() and i < target.size()) { // recursive call to compare array values at index i @@ -10002,9 +14261,12 @@ basic_json_parser_63: // in a second pass, traverse the remaining elements // remove my remaining elements + const auto end_index = static_cast<difference_type>(result.size()); while (i < source.size()) { - result.push_back(object( + // add operations in reverse order to avoid invalid + // indices + result.insert(result.begin() + end_index, object( { {"op", "remove"}, {"path", path + "/" + std::to_string(i)} @@ -10030,7 +14292,7 @@ basic_json_parser_63: case value_t::object: { // first pass: traverse this object's elements - for (auto it = source.begin(); it != source.end(); ++it) + for (auto it = source.cbegin(); it != source.cend(); ++it) { // escape the key name to be used in a JSON patch const auto key = json_pointer::escape(it.key()); @@ -10046,14 +14308,13 @@ basic_json_parser_63: // found a key that is not in o -> remove it result.push_back(object( { - {"op", "remove"}, - {"path", path + "/" + key} + {"op", "remove"}, {"path", path + "/" + key} })); } } // second pass: traverse other object's elements - for (auto it = target.begin(); it != target.end(); ++it) + for (auto it = target.cbegin(); it != target.cend(); ++it) { if (source.find(it.key()) == source.end()) { @@ -10061,8 +14322,7 @@ basic_json_parser_63: const auto key = json_pointer::escape(it.key()); result.push_back( { - {"op", "add"}, - {"path", path + "/" + key}, + {"op", "add"}, {"path", path + "/" + key}, {"value", it.value()} }); } @@ -10076,9 +14336,7 @@ basic_json_parser_63: // both primitive type: replace value result.push_back( { - {"op", "replace"}, - {"path", path}, - {"value", target} + {"op", "replace"}, {"path", path}, {"value", target} }); break; } @@ -10091,7 +14349,6 @@ basic_json_parser_63: /// @} }; - ///////////// // presets // ///////////// @@ -10105,8 +14362,402 @@ uses the standard template types. @since version 1.0.0 */ using json = basic_json<>; + +////////////////// +// json_pointer // +////////////////// + +NLOHMANN_BASIC_JSON_TPL_DECLARATION +NLOHMANN_BASIC_JSON_TPL& +json_pointer::get_and_create(NLOHMANN_BASIC_JSON_TPL& j) const +{ + using size_type = typename NLOHMANN_BASIC_JSON_TPL::size_type; + auto result = &j; + + // in case no reference tokens exist, return a reference to the JSON value + // j which will be overwritten by a primitive value + for (const auto& reference_token : reference_tokens) + { + switch (result->m_type) + { + case detail::value_t::null: + { + if (reference_token == "0") + { + // start a new array if reference token is 0 + result = &result->operator[](0); + } + else + { + // start a new object otherwise + result = &result->operator[](reference_token); + } + break; + } + + case detail::value_t::object: + { + // create an entry in the object + result = &result->operator[](reference_token); + break; + } + + case detail::value_t::array: + { + // create an entry in the array + JSON_TRY + { + result = &result->operator[](static_cast<size_type>(array_index(reference_token))); + } + JSON_CATCH(std::invalid_argument&) + { + JSON_THROW(detail::parse_error::create(109, 0, "array index '" + reference_token + "' is not a number")); + } + break; + } + + /* + The following code is only reached if there exists a reference + token _and_ the current value is primitive. In this case, we have + an error situation, because primitive values may only occur as + single value; that is, with an empty list of reference tokens. + */ + default: + JSON_THROW(detail::type_error::create(313, "invalid value to unflatten")); + } + } + + return *result; +} + +NLOHMANN_BASIC_JSON_TPL_DECLARATION +NLOHMANN_BASIC_JSON_TPL& +json_pointer::get_unchecked(NLOHMANN_BASIC_JSON_TPL* ptr) const +{ + using size_type = typename NLOHMANN_BASIC_JSON_TPL::size_type; + for (const auto& reference_token : reference_tokens) + { + // convert null values to arrays or objects before continuing + if (ptr->m_type == detail::value_t::null) + { + // check if reference token is a number + const bool nums = + std::all_of(reference_token.begin(), reference_token.end(), + [](const char x) + { + return (x >= '0' and x <= '9'); + }); + + // change value to array for numbers or "-" or to object otherwise + *ptr = (nums or reference_token == "-") + ? detail::value_t::array + : detail::value_t::object; + } + + switch (ptr->m_type) + { + case detail::value_t::object: + { + // use unchecked object access + ptr = &ptr->operator[](reference_token); + break; + } + + case detail::value_t::array: + { + // error condition (cf. RFC 6901, Sect. 4) + if (JSON_UNLIKELY(reference_token.size() > 1 and reference_token[0] == '0')) + { + JSON_THROW(detail::parse_error::create(106, 0, + "array index '" + reference_token + + "' must not begin with '0'")); + } + + if (reference_token == "-") + { + // explicitly treat "-" as index beyond the end + ptr = &ptr->operator[](ptr->m_value.array->size()); + } + else + { + // convert array index to number; unchecked access + JSON_TRY + { + ptr = &ptr->operator[]( + static_cast<size_type>(array_index(reference_token))); + } + JSON_CATCH(std::invalid_argument&) + { + JSON_THROW(detail::parse_error::create(109, 0, "array index '" + reference_token + "' is not a number")); + } + } + break; + } + + default: + JSON_THROW(detail::out_of_range::create(404, "unresolved reference token '" + reference_token + "'")); + } + } + + return *ptr; +} + +NLOHMANN_BASIC_JSON_TPL_DECLARATION +NLOHMANN_BASIC_JSON_TPL& +json_pointer::get_checked(NLOHMANN_BASIC_JSON_TPL* ptr) const +{ + using size_type = typename NLOHMANN_BASIC_JSON_TPL::size_type; + for (const auto& reference_token : reference_tokens) + { + switch (ptr->m_type) + { + case detail::value_t::object: + { + // note: at performs range check + ptr = &ptr->at(reference_token); + break; + } + + case detail::value_t::array: + { + if (JSON_UNLIKELY(reference_token == "-")) + { + // "-" always fails the range check + JSON_THROW(detail::out_of_range::create(402, + "array index '-' (" + std::to_string(ptr->m_value.array->size()) + + ") is out of range")); + } + + // error condition (cf. RFC 6901, Sect. 4) + if (JSON_UNLIKELY(reference_token.size() > 1 and reference_token[0] == '0')) + { + JSON_THROW(detail::parse_error::create(106, 0, + "array index '" + reference_token + + "' must not begin with '0'")); + } + + // note: at performs range check + JSON_TRY + { + ptr = &ptr->at(static_cast<size_type>(array_index(reference_token))); + } + JSON_CATCH(std::invalid_argument&) + { + JSON_THROW(detail::parse_error::create(109, 0, "array index '" + reference_token + "' is not a number")); + } + break; + } + + default: + JSON_THROW(detail::out_of_range::create(404, "unresolved reference token '" + reference_token + "'")); + } + } + + return *ptr; +} + +NLOHMANN_BASIC_JSON_TPL_DECLARATION +const NLOHMANN_BASIC_JSON_TPL& +json_pointer::get_unchecked(const NLOHMANN_BASIC_JSON_TPL* ptr) const +{ + using size_type = typename NLOHMANN_BASIC_JSON_TPL::size_type; + for (const auto& reference_token : reference_tokens) + { + switch (ptr->m_type) + { + case detail::value_t::object: + { + // use unchecked object access + ptr = &ptr->operator[](reference_token); + break; + } + + case detail::value_t::array: + { + if (JSON_UNLIKELY(reference_token == "-")) + { + // "-" cannot be used for const access + JSON_THROW(detail::out_of_range::create(402, + "array index '-' (" + std::to_string(ptr->m_value.array->size()) + + ") is out of range")); + } + + // error condition (cf. RFC 6901, Sect. 4) + if (JSON_UNLIKELY(reference_token.size() > 1 and reference_token[0] == '0')) + { + JSON_THROW(detail::parse_error::create(106, 0, + "array index '" + reference_token + + "' must not begin with '0'")); + } + + // use unchecked array access + JSON_TRY + { + ptr = &ptr->operator[]( + static_cast<size_type>(array_index(reference_token))); + } + JSON_CATCH(std::invalid_argument&) + { + JSON_THROW(detail::parse_error::create(109, 0, "array index '" + reference_token + "' is not a number")); + } + break; + } + + default: + JSON_THROW(detail::out_of_range::create(404, "unresolved reference token '" + reference_token + "'")); + } + } + + return *ptr; +} + +NLOHMANN_BASIC_JSON_TPL_DECLARATION +const NLOHMANN_BASIC_JSON_TPL& +json_pointer::get_checked(const NLOHMANN_BASIC_JSON_TPL* ptr) const +{ + using size_type = typename NLOHMANN_BASIC_JSON_TPL::size_type; + for (const auto& reference_token : reference_tokens) + { + switch (ptr->m_type) + { + case detail::value_t::object: + { + // note: at performs range check + ptr = &ptr->at(reference_token); + break; + } + + case detail::value_t::array: + { + if (JSON_UNLIKELY(reference_token == "-")) + { + // "-" always fails the range check + JSON_THROW(detail::out_of_range::create(402, + "array index '-' (" + std::to_string(ptr->m_value.array->size()) + + ") is out of range")); + } + + // error condition (cf. RFC 6901, Sect. 4) + if (JSON_UNLIKELY(reference_token.size() > 1 and reference_token[0] == '0')) + { + JSON_THROW(detail::parse_error::create(106, 0, + "array index '" + reference_token + + "' must not begin with '0'")); + } + + // note: at performs range check + JSON_TRY + { + ptr = &ptr->at(static_cast<size_type>(array_index(reference_token))); + } + JSON_CATCH(std::invalid_argument&) + { + JSON_THROW(detail::parse_error::create(109, 0, "array index '" + reference_token + "' is not a number")); + } + break; + } + + default: + JSON_THROW(detail::out_of_range::create(404, "unresolved reference token '" + reference_token + "'")); + } + } + + return *ptr; +} + +NLOHMANN_BASIC_JSON_TPL_DECLARATION +void json_pointer::flatten(const std::string& reference_string, + const NLOHMANN_BASIC_JSON_TPL& value, + NLOHMANN_BASIC_JSON_TPL& result) +{ + switch (value.m_type) + { + case detail::value_t::array: + { + if (value.m_value.array->empty()) + { + // flatten empty array as null + result[reference_string] = nullptr; + } + else + { + // iterate array and use index as reference string + for (std::size_t i = 0; i < value.m_value.array->size(); ++i) + { + flatten(reference_string + "/" + std::to_string(i), + value.m_value.array->operator[](i), result); + } + } + break; + } + + case detail::value_t::object: + { + if (value.m_value.object->empty()) + { + // flatten empty object as null + result[reference_string] = nullptr; + } + else + { + // iterate object and use keys as reference string + for (const auto& element : *value.m_value.object) + { + flatten(reference_string + "/" + escape(element.first), element.second, result); + } + } + break; + } + + default: + { + // add primitive value with its reference string + result[reference_string] = value; + break; + } + } } +NLOHMANN_BASIC_JSON_TPL_DECLARATION +NLOHMANN_BASIC_JSON_TPL +json_pointer::unflatten(const NLOHMANN_BASIC_JSON_TPL& value) +{ + if (JSON_UNLIKELY(not value.is_object())) + { + JSON_THROW(detail::type_error::create(314, "only objects can be unflattened")); + } + + NLOHMANN_BASIC_JSON_TPL result; + + // iterate the JSON object values + for (const auto& element : *value.m_value.object) + { + if (JSON_UNLIKELY(not element.second.is_primitive())) + { + JSON_THROW(detail::type_error::create(315, "values in object must be primitive")); + } + + // assign value to reference pointed to by JSON pointer; Note that if + // the JSON pointer is "" (i.e., points to the whole value), function + // get_and_create returns a reference to result itself. An assignment + // will then create a primitive value. + json_pointer(element.first).get_and_create(result) = element.second; + } + + return result; +} + +inline bool operator==(json_pointer const& lhs, json_pointer const& rhs) noexcept +{ + return (lhs.reference_tokens == rhs.reference_tokens); +} + +inline bool operator!=(json_pointer const& lhs, json_pointer const& rhs) noexcept +{ + return not (lhs == rhs); +} +} // namespace nlohmann + /////////////////////// // nonmember support // @@ -10120,7 +14771,7 @@ namespace std @since version 1.0.0 */ -template <> +template<> inline void swap(nlohmann::json& j1, nlohmann::json& j2) noexcept( is_nothrow_move_constructible<nlohmann::json>::value and @@ -10131,7 +14782,7 @@ inline void swap(nlohmann::json& j1, } /// hash value for JSON objects -template <> +template<> struct hash<nlohmann::json> { /*! @@ -10146,38 +14797,78 @@ struct hash<nlohmann::json> return h(j.dump()); } }; -} + +/// specialization for std::less<value_t> +/// @note: do not remove the space after '<', +/// see https://github.com/nlohmann/json/pull/679 +template<> +struct less< ::nlohmann::detail::value_t> +{ + /*! + @brief compare two value_t enum values + @since version 3.0.0 + */ + bool operator()(nlohmann::detail::value_t lhs, + nlohmann::detail::value_t rhs) const noexcept + { + return nlohmann::detail::operator<(lhs, rhs); + } +}; + +} // namespace std /*! @brief user-defined string literal for JSON values This operator implements a user-defined string literal for JSON objects. It -can be used by adding \p "_json" to a string literal and returns a JSON object +can be used by adding `"_json"` to a string literal and returns a JSON object if no parse error occurred. @param[in] s a string representation of a JSON object +@param[in] n the length of string @a s @return a JSON object @since version 1.0.0 */ -inline nlohmann::json operator "" _json(const char* s, std::size_t) +inline nlohmann::json operator "" _json(const char* s, std::size_t n) { - return nlohmann::json::parse(reinterpret_cast<const nlohmann::json::string_t::value_type*>(s)); + return nlohmann::json::parse(s, s + n); } /*! @brief user-defined string literal for JSON pointer +This operator implements a user-defined string literal for JSON Pointers. It +can be used by adding `"_json_pointer"` to a string literal and returns a JSON pointer +object if no parse error occurred. + +@param[in] s a string representation of a JSON Pointer +@param[in] n the length of string @a s +@return a JSON pointer object + @since version 2.0.0 */ -inline nlohmann::json::json_pointer operator "" _json_pointer(const char* s, std::size_t) +inline nlohmann::json::json_pointer operator "" _json_pointer(const char* s, std::size_t n) { - return nlohmann::json::json_pointer(s); + return nlohmann::json::json_pointer(std::string(s, n)); } // restore GCC/clang diagnostic settings #if defined(__clang__) || defined(__GNUC__) || defined(__GNUG__) #pragma GCC diagnostic pop #endif +#if defined(__clang__) + #pragma GCC diagnostic pop +#endif + +// clean up +#undef JSON_CATCH +#undef JSON_THROW +#undef JSON_TRY +#undef JSON_LIKELY +#undef JSON_UNLIKELY +#undef JSON_DEPRECATED +#undef NLOHMANN_BASIC_JSON_TPL_DECLARATION +#undef NLOHMANN_BASIC_JSON_TPL #endif |