module type S = sig end
type key
type 'a
t
val create : int -> 'a t
val clear : 'a t -> unit
val copy : 'a t -> 'a t
val add : 'a t -> key:key -> data:'a -> unit
val remove : 'a t -> key -> unit
val find : 'a t -> key -> 'a
val find_all : 'a t -> key -> 'a list
val replace : 'a t -> key:key -> data:'a -> unit
val mem : 'a t -> key -> bool
val iter : f:(key:key -> data:'a -> unit) ->
'a t -> unit
val fold : f:(key:key -> data:'a -> 'b -> 'b) ->
'a t -> init:'b -> 'b