(* Lightweight thread library for OCaml
 * http://www.ocsigen.org/lwt
 * Interface Lwt_pqueue
 * Copyright (C) 1999-2004 Jérôme Vouillon
 * Laboratoire PPS - CNRS Université Paris Diderot
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU Lesser General Public License as
 * published by the Free Software Foundation, with linking exceptions;
 * either version 2.1 of the License, or (at your option) any later
 * version. See COPYING file for details.
 *
 * This program 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.  See the GNU
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with this program; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA
 * 02111-1307, USA.
 *)

module type OrderedType =
  sig
    type t
    val compare: t -> t -> int
  end

module type S =
  sig
    type elt
    type t
    val empty: t
    val is_empty: t -> bool
    val add: elt -> t -> t
    val union: t -> t -> t
    val find_min: t -> elt
    val lookup_min: t -> elt option
    val remove_min: t -> t
    val size: t -> int
  end

module Make(Ord: OrderedType) : S with type elt = Ord.t
