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From: =?utf-8?Q?S=C3=A9bastien?= Hinderer <Sebastien.Hinderer@inria.fr>
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Subject: [Caml-list] Polymorphic hash tables

Hi,

Is there a way to just replace OCaml's standard hash function for some
tables?

Here is an example:

module MyHashedType : Hashtbl.HashedType = struct
  type t
  let my_n = 20
  let my_m = 30
  let equal = (=)
  let hash = Hashtbl.hash_param my_n my_m
end

module MyHashtbl = Hashtbl.Make(MyHashedType)

let (mytbl : int MyHashtbl.t) = MyHashtbl.create 100

With this example polymorphism seems to be lost and the compiler does
not accept something like
type t = 'a
to retrieve a generic type as for the standard hash tables.

Any suggestion?

Thanks a lot.
Sébastien.