`sig
type key
type 'a t
val create : int -> 'a Hashtbl.S.t
val clear : 'a Hashtbl.S.t -> unit
val reset : 'a Hashtbl.S.t -> unit
val copy : 'a Hashtbl.S.t -> 'a Hashtbl.S.t
val add : 'a Hashtbl.S.t -> Hashtbl.S.key -> 'a -> unit
val remove : 'a Hashtbl.S.t -> Hashtbl.S.key -> unit
val find : 'a Hashtbl.S.t -> Hashtbl.S.key -> 'a
val find_opt : 'a Hashtbl.S.t -> Hashtbl.S.key -> 'a option
val find_all : 'a Hashtbl.S.t -> Hashtbl.S.key -> 'a list
val replace : 'a Hashtbl.S.t -> Hashtbl.S.key -> 'a -> unit
val mem : 'a Hashtbl.S.t -> Hashtbl.S.key -> bool
val iter : (Hashtbl.S.key -> 'a -> unit) -> 'a Hashtbl.S.t -> unit
val filter_map_inplace :
(Hashtbl.S.key -> 'a -> 'a option) -> 'a Hashtbl.S.t -> unit
val fold : (Hashtbl.S.key -> 'a -> 'b -> 'b) -> 'a Hashtbl.S.t -> 'b -> 'b
val length : 'a Hashtbl.S.t -> int
val stats : 'a Hashtbl.S.t -> Hashtbl.statistics
val to_seq : 'a Hashtbl.S.t -> (Hashtbl.S.key * 'a) Stdlib.Seq.t
val to_seq_keys : 'a Hashtbl.S.t -> Hashtbl.S.key Stdlib.Seq.t
val to_seq_values : 'a Hashtbl.S.t -> 'a Stdlib.Seq.t
val add_seq : 'a Hashtbl.S.t -> (Hashtbl.S.key * 'a) Stdlib.Seq.t -> unit
val replace_seq :
'a Hashtbl.S.t -> (Hashtbl.S.key * 'a) Stdlib.Seq.t -> unit
val of_seq : (Hashtbl.S.key * 'a) Stdlib.Seq.t -> 'a Hashtbl.S.t
end`