(* 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/.
 *)

(*  AUTORS: Ferruccio Guidi        <fguidi@cs.unibo.it>
 *          Claudio Sacerdoti Coen <sacerdot@cs.unibo.it> 
 *)

(* low level types  *********************************************************)

type uri = string
type position = MainHypothesis
              | InHypothesis
              | MainConclusion
              | InConclusion
              | InBody
type depth = int
type sort = Set
          | Prop
          | Type
	  | CProp
 
type spec = MustObj  of uri list * position list * depth list
          | MustSort of sort list * position list * depth list
	  | MustRel  of position list * depth list
	  | OnlyObj  of uri list * position list * depth list
          | OnlySort of sort list * position list * depth list
	  | OnlyRel  of position list * depth list
	  | Universe of position list 

(* high-level types  ********************************************************)

type optional_depth = int option

type full_position  = [ `MainHypothesis of optional_depth
                      | `MainConclusion of optional_depth
                      | `InHypothesis
                      | `InConclusion
                      | `InBody
                      ]

type main_position = [ `MainHypothesis of optional_depth
                     | `MainConclusion of optional_depth
                     ]
                   
type r_obj  = full_position * uri
type r_sort = main_position * sort
type r_rel  = main_position 

type must_restrictions = (r_obj list * r_rel list * r_sort list)
type only_restrictions =
   (r_obj list option * r_rel list option * r_sort list option)

type universe = position list