Ephemeron.K2val make : 'k1 -> 'k2 -> 'd -> ('k1, 'k2, 'd) tval query : ('k1, 'k2, 'd) t -> 'k1 -> 'k2 -> 'd optionmodule Make (H1 : Hashtbl.HashedType) (H2 : Hashtbl.HashedType) : sig ... endmodule MakeSeeded (H1 : sig ... end) (H2 : sig ... end) : sig ... endmodule Bucket : sig ... end