(* Copyright (C) 2004, 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://helm.cs.unibo.it/
 *)

open CicTextualParser2

EXTEND
  term: LEVEL "add"
    [
      [ t1 = term; SYMBOL "+"; t2 = term ->
          return_term loc (CicAst.Appl [CicAst.Symbol ("plus", 0); t1; t2])
      | t1 = term; SYMBOL "-"; t2 = term ->
          return_term loc (CicAst.Appl [CicAst.Symbol ("minus", 0); t1; t2])
      ]
    ];
  term: LEVEL "mult"
    [
      [ t1 = term; SYMBOL "*"; t2 = term ->
          return_term loc (CicAst.Appl [CicAst.Symbol ("times", 0); t1; t2])
      | t1 = term; SYMBOL "/"; t2 = term ->
          return_term loc (CicAst.Appl [CicAst.Symbol ("divide", 0); t1; t2])
      ]
    ];
  term: LEVEL "inv"
    [
      [ SYMBOL "-"; t = term ->
        return_term loc (CicAst.Appl [CicAst.Symbol ("uminus", 0); t])
      ]
    ];
  term: LEVEL "relop"
    [
      [ t1 = term; SYMBOL <:unicode<leq>> (* ≤ *); t2 = term ->
          return_term loc (CicAst.Appl [CicAst.Symbol ("leq", 0); t1; t2])
      | t1 = term; SYMBOL <:unicode<geq>> (* ≥ *); t2 = term ->
          return_term loc (CicAst.Appl [CicAst.Symbol ("geq", 0); t1; t2])
      | t1 = term; SYMBOL "<"; t2 = term ->
          return_term loc (CicAst.Appl [CicAst.Symbol ("lt", 0); t1; t2])
      | t1 = term; SYMBOL ">"; t2 = term ->
          return_term loc (CicAst.Appl [CicAst.Symbol ("gt", 0); t1; t2])
      | t1 = term; SYMBOL <:unicode<ne>> (* ≠ *); t2 = term ->
          return_term loc (CicAst.Appl [CicAst.Symbol ("neq", 0); t1; t2])
      ]
    ];
END

let _ =
  let const s = Cic.Const (s, []) in
  let mutind s = Cic.MutInd (s, 0, []) in

  DisambiguateChoices.add_num_choice
    ("natural number",
      (fun _ num _ -> HelmLibraryObjects.build_nat (int_of_string num)));
  DisambiguateChoices.add_num_choice
    ("real number",
      (fun _ num _ -> HelmLibraryObjects.build_real (int_of_string num)));

  DisambiguateChoices.add_binary_op "plus" "natural plus"
    HelmLibraryObjects.Peano.plus;
  DisambiguateChoices.add_binary_op "plus" "real plus"
    HelmLibraryObjects.Reals.rplus;
  DisambiguateChoices.add_binary_op "minus" "natural minus"
    (const HelmLibraryObjects.Peano.minus_URI);
  DisambiguateChoices.add_binary_op "minus" "real minus"
    (const HelmLibraryObjects.Reals.rminus_URI);
  DisambiguateChoices.add_binary_op "times" "natural times"
    (const HelmLibraryObjects.Peano.mult_URI);
  DisambiguateChoices.add_binary_op "times" "real times"
    (const HelmLibraryObjects.Reals.rmult_URI);
  DisambiguateChoices.add_binary_op "divide" "real divide"
    (const HelmLibraryObjects.Reals.rdiv_URI);
  DisambiguateChoices.add_unary_op "uminus" "real unary minus"
    (const HelmLibraryObjects.Reals.ropp_URI);

  DisambiguateChoices.add_binary_op "leq" "natural 'less or equal to'"
    (mutind HelmLibraryObjects.Peano.le_URI);
  DisambiguateChoices.add_binary_op "leq" "real 'less or equal to'"
    (const HelmLibraryObjects.Reals.rle_URI);
  DisambiguateChoices.add_binary_op "geq" "natural 'greater or equal to'"
    (const HelmLibraryObjects.Peano.ge_URI);
  DisambiguateChoices.add_binary_op "geq" "real 'greater or equal to'"
    (const HelmLibraryObjects.Reals.rge_URI);
  DisambiguateChoices.add_binary_op "lt" "natural 'less than'"
    (const HelmLibraryObjects.Peano.lt_URI);
  DisambiguateChoices.add_binary_op "lt" "real 'less than'"
    (const HelmLibraryObjects.Reals.rlt_URI);
  DisambiguateChoices.add_binary_op "gt" "natural 'greater than'"
    (const HelmLibraryObjects.Peano.gt_URI);
  DisambiguateChoices.add_binary_op "gt" "real 'greater than'"
    (const HelmLibraryObjects.Reals.rgt_URI);
  DisambiguateChoices.add_symbol_choice "neq"
    ("not equal to (leibnitz)",
      (fun env _ args ->
        let t1, t2 =
          match args with 
          | [t1; t2] -> t1, t2
          | _ -> raise DisambiguateChoices.Invalid_choice
        in
        Cic.Appl [ const HelmLibraryObjects.Logic.not_URI;
          Cic.Appl [
            Cic.MutInd (HelmLibraryObjects.Logic.eq_URI, 0, []);
              Cic.Implicit (Some `Type); t1; t2 ] ]));
  DisambiguateChoices.add_symbol_choice "neq"
    ("not equal to (sort Type)",
      (fun env _ args ->
        let t1, t2 =
          match args with
          | [t1; t2] -> t1, t2
          | _ -> raise DisambiguateChoices.Invalid_choice
        in
        Cic.Appl [ const HelmLibraryObjects.Logic.not_URI;
          Cic.Appl [
            Cic.MutInd (HelmLibraryObjects.Logic_Type.eqt_URI, 0, []);
              Cic.Implicit (Some `Type); t1; t2 ] ]));