Merge of the V7_3_new_exportation branch.

[helm.git] / helm / ocaml / tactics / negationTactics.ml

diff --git a/helm/ocaml/tactics/negationTactics.ml b/helm/ocaml/tactics/negationTactics.ml
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+(* Copyright (C) 2002, 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/.
+ *)
+
+
+let absurd_tac ~term ~status:((proof,goal) as status) =
+  let module C = Cic in
+  let module U = UriManager in
+  let module P = PrimitiveTactics in
+   let _,metasenv,_,_ = proof in
+    let _,context,ty = List.find (function (m,_,_) -> m=goal) metasenv in
+     if ((CicTypeChecker.type_of_aux' metasenv context term) = (C.Sort C.Prop)) (* ma questo controllo serve?? *)
+      then P.apply_tac 
+              ~term:(C.Appl [(C.Const ((U.uri_of_string "cic:/Coq/Init/Logic/absurd.con") , [] )) ; term ; ty]) ~status
+      else raise (ProofEngineTypes.Fail "Absurd: Not a Proposition")
+;;
+
+
+let contradiction_tac ~status =
+  let module C = Cic in
+  let module U = UriManager in
+  let module P = PrimitiveTactics in
+  let module T = Tacticals in
+   try
+    T.then_
+      ~start:(P.intros_tac ())
+      ~continuation:(
+        T.then_
+           ~start:
+             (EliminationTactics.elim_type_tac 
+                ~term:
+                  (C.MutInd ((U.uri_of_string "cic:/Coq/Init/Logic/False.ind"), 0, [])))
+           ~continuation: VariousTactics.assumption_tac)
+    ~status
+   with 
+    (ProofEngineTypes.Fail "Assumption: No such assumption") -> raise (ProofEngineTypes.Fail "Contradiction: No such assumption")
+    (* sarebbe piu' elegante se Assumtion sollevasse un'eccezione tutta sua che questa cattura, magari con l'aiuto di try_tactics *)
+;;
+
+(* Questa era in fourierR.ml
+(* !!!!! fix !!!!!!!!!! *)
+let contradiction_tac ~status:(proof,goal)=
+        Tacticals.then_
+                ~start:(PrimitiveTactics.intros_tac ~name:"bo?" ) (*inutile sia questo che quello prima  della chiamata*)
+                ~continuation:(Tacticals.then_
+                        ~start:(VariousTactics.elim_type_tac ~term:_False)
+                        ~continuation:(assumption_tac))
+        ~status:(proof,goal)
+;;
+*)
+
+