diff options
Diffstat (limited to 'src')
| -rw-r--r-- | src/vytree.ml | 25 | ||||
| -rw-r--r-- | src/vytree.mli | 3 |
2 files changed, 28 insertions, 0 deletions
diff --git a/src/vytree.ml b/src/vytree.ml index 7c4e4fb..6ecc867 100644 --- a/src/vytree.ml +++ b/src/vytree.ml @@ -306,3 +306,28 @@ let fold_tree_with_path f (p', a) t = List.fold_left (fold_func f) (f (p, a) t) c in (Util.drop_first p), snd res in snd (fold_func f (p', a) t) + +(** Allow function called in fold to maintain a list of values for each + depth level of tree. A simple example is for the the function to cons a + boolean value to the list v at each call of the depth-first traversal; + at the return to local root, the value for that level is restored. + Note that if the function returns the empty list, this function reduces + to fold_tree_with_path. + *) + +let fold_tree_with_path_and_list f ((p', v), a) t = + let rec fold_func f ((p', v), a) t = + let p = + match name_of_node t with + | "" -> p' + | name -> name :: p' + in + let children = children_of_node t in + match children with + | [] -> let res = + f ((p, v), a) t in + (Util.drop_first p, Util.drop_first (snd (fst res))), snd res + | c -> let res = + List.fold_left (fold_func f) (f ((p, v), a) t) c in + (Util.drop_first p, Util.drop_first (snd (fst res))), snd res + in snd (fold_func f ((p', v), a) t) diff --git a/src/vytree.mli b/src/vytree.mli index 023d967..448aa84 100644 --- a/src/vytree.mli +++ b/src/vytree.mli @@ -96,3 +96,6 @@ val is_terminal_path : 'a t -> string list -> bool [@@alert exn "Vytree.Empty_path"] val fold_tree_with_path: (string list * 'acc -> 'b t -> string list * 'acc) -> string list * 'acc -> 'b t -> 'acc + +val fold_tree_with_path_and_list: ((string list * bool list) * 'acc -> 'b t -> + (string list * bool list) * 'acc) -> (string list * bool list) * 'acc -> 'b t -> 'acc |