(* Copyright (C) 2000, HELM Team.
 * 
 * This file is part of HELM, an Hypertextual, Electronic
 * Library of Mathematics, developed at the Computer Science
 * Department, University of Bologna, Italy.
 * 
 * HELM is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License
 * as published by the Free Software Foundation; either version 2
 * of the License, or (at your option) any later version.
 * 
 * HELM 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 General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with HELM; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place - Suite 330, Boston,
 * MA  02111-1307, USA.
 * 
 * For details, see the HELM World-Wide-Web page,
 * http://cs.unibo.it/helm/.
 *)

(*  AUTOR: Ferruccio Guidi <fguidi@cs.unibo.it>
 *)

val text_of_query  : (string -> unit) -> MathQL.query -> string -> unit

val text_of_result : (string -> unit) -> MathQL.result -> string -> unit

val query_of_text  : Lexing.lexbuf -> MathQL.query

val result_of_text : Lexing.lexbuf -> MathQL.result

type time

val start_time : unit -> time

val stop_time  : time -> string

type 'a comparison = Lt 
                   | Gt
		   | Eq of 'a

val list_join : ('a -> 'a -> 'a comparison) -> 'a list -> 'a list -> 'a list 

val list_meet : ('a -> 'a -> 'a comparison) -> 'a list -> 'a list -> 'a list