(**************************************************************************)
(* *)
(* Copyright (C) Francois Bobot, Jean-Christophe Filliatre, *)
(* Johannes Kanig and Andrei Paskevich. *)
(* *)
(* This software is free software; you can redistribute it and/or *)
(* modify it under the terms of the GNU Library General Public *)
(* License version 2.1, with the special exception on linking *)
(* described in file LICENSE. *)
(* *)
(* This software is distributed in the hope that it will be useful, *)
(* but WITHOUT ANY WARRANTY; without even the implied warranty of *)
(* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. *)
(* *)
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(*s Hash tables for hash consing.
Hash consed values are of the
following type [hash_consed]. The field [tag] contains a unique
integer (for values hash consed with the same table). The field
[hkey] contains the hash key of the value (without modulo) for
possible use in other hash tables (and internally when hash
consing tables are resized). The field [node] contains the value
itself.
Hash consing tables are using weak pointers, so that values that are no
more referenced from anywhere else can be erased by the GC. *)
module type HashedType =
sig
type t
val equal : t -> t -> bool
val hash : t -> int
val tag : int -> t -> t
end
module type S =
sig
type t
val hashcons : t -> t
(** [hashcons n f] hash-cons the value [n] using function [f] i.e. returns
any existing value in the table equal to [n], if any;
otherwise, creates a new value with function [f], stores it
in the table and returns it. Function [f] is passed
the node [n] as first argument and the unique id as second argument.
*)
val iter : (t -> unit) -> unit
(** [iter f] iterates [f] over all elements of the table . *)
val stats : unit -> int * int * int * int * int * int
(** Return statistics on the table. The numbers are, in order:
table length, number of entries, sum of bucket lengths,
smallest bucket length, median bucket length, biggest
bucket length. *)
end
module Make(H : HashedType) : (S with type t = H.t)
(* helpers *)
val combine : int -> int -> int
val combine2 : int -> int -> int -> int
val combine3 : int -> int -> int -> int -> int
val combine_list : ('a -> int) -> int -> 'a list -> int