functor (Key1 : Key) (Key2 : Key) ->
sig
type 'data t = (Key1.t, Key2.t, 'data) t
val equal : 'a Core.Std.Equal.equal -> 'a t Core.Std.Equal.equal
val create : unit -> 'data Hashtbl2.t
val sexp_of_t :
('data -> Sexplib.Sexp.t) -> 'data Hashtbl2.t -> Sexplib.Sexp.t
end