`sig
type 'a out_value
type ('key, 'data) t = private
('key, 'data Fold_map.S2.out_value) Core.Std.Map.Poly.t
type 'a _in_value = 'a
type 'a _out_value = 'a Fold_map.S2.out_value
type ('a, 'b) _t = ('a, 'b) Fold_map.S2.t
val empty : ('a, 'b) Fold_map.S2.t
val singleton : 'a -> 'b -> ('a, 'b) Fold_map.S2.t
val is_empty : ('a, 'b) Fold_map.S2.t -> bool
val length : ('a, 'b) Fold_map.S2.t -> int
val add :
key:'a -> data:'b -> ('a, 'b) Fold_map.S2.t -> ('a, 'b) Fold_map.S2.t
val find : ('a, 'b) Fold_map.S2.t -> 'a -> 'b Fold_map.S2.out_value
val remove : ('a, 'b) Fold_map.S2.t -> 'a -> ('a, 'b) Fold_map.S2.t
val set :
key:'a ->
data:'b Fold_map.S2.out_value ->
('a, 'b) Fold_map.S2.t -> ('a, 'b) Fold_map.S2.t
val mem : ('a, 'b) Fold_map.S2.t -> 'a -> bool
val iter :
('a, 'b) Fold_map.S2.t ->
f:(key:'a -> data:'b Fold_map.S2.out_value -> unit) -> unit
val fold :
('a, 'b) Fold_map.S2.t ->
init:'c -> f:(key:'a -> data:'b Fold_map.S2.out_value -> 'c -> 'c) -> 'c
val filter :
('a, 'b) Fold_map.S2.t ->
f:(key:'a -> data:'b Fold_map.S2.out_value -> bool) ->
('a, 'b) Fold_map.S2.t
val keys : ('a, 'b) Fold_map.S2.t -> 'a list
val data : ('a, 'b) Fold_map.S2.t -> 'b Fold_map.S2.out_value list
val to_alist :
('a, 'b) Fold_map.S2.t -> ('a * 'b Fold_map.S2.out_value) list
val of_list : ('a * 'b) list -> ('a, 'b) Fold_map.S2.t
val for_all :
('a, 'b) Fold_map.S2.t -> f:('b Fold_map.S2.out_value -> bool) -> bool
val exists :
('a, 'b) Fold_map.S2.t -> f:('b Fold_map.S2.out_value -> bool) -> bool
val to_map :
('a, 'b) Fold_map.S2.t ->
('a, 'b Fold_map.S2.out_value) Core.Std.Map.Poly.t
val of_map :
('a, 'b Fold_map.S2.out_value) Core.Std.Map.Poly.t ->
('a, 'b) Fold_map.S2.t
end`