(* 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>
 *)

exception NumberError of MathQL.result

val val_true      : MathQL.result

val val_false     : MathQL.result

val grp_make_x    : MathQL.path -> MathQL.value -> MathQL.group

val x_grp_make_x  : MathQL.path -> MathQL.result -> MathQL.group

val grp_iter      : ('a -> MathQL.group) -> 'a list -> MathQL.group

val grp_iter2     : ('a -> 'b -> MathQL.group) -> 
                    'a list -> 'b list -> MathQL.group 
		    
val make_x        : string -> MathQL.group list -> MathQL.result

val iter          : ('a -> MathQL.result) -> 'a list -> MathQL.result

val count         : MathQL.result -> int

val avs_of_bool   : bool -> MathQL.result 

val bool_of_avs    : MathQL.result -> bool

val avs_of_int    : int -> MathQL.result 

val int_of_avs    : MathQL.result -> int

val subj          : MathQL.value -> MathQL.result

val avs_of_string : string -> MathQL.result

val string_of_avs : MathQL.result -> string option