--- /dev/null
+(* 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/.
+ *)
+
+(* $Id$ *)
+
+module C = Cic
+module U = UriManager
+module PET = ProofEngineTypes
+module PER = ProofEngineReduction
+module PEH = ProofEngineHelpers
+module PESR = ProofEngineStructuralRules
+module P = PrimitiveTactics
+module T = Tacticals
+module R = CicReduction
+module S = CicSubstitution
+module TC = CicTypeChecker
+module LO = LibraryObjects
+module DTI = DoubleTypeInference
+module HEL = HExtlib
+
+let rec rewrite_tac ~direction ~pattern:(wanted,hyps_pat,concl_pat) equality =
+ let _rewrite_tac status =
+ assert (wanted = None); (* this should be checked syntactically *)
+ let proof,goal = status in
+ let curi, metasenv, _subst, pbo, pty, attrs = proof in
+ let (metano,context,gty) = CicUtil.lookup_meta goal metasenv in
+ let gsort,_ =
+ CicTypeChecker.type_of_aux' metasenv context gty CicUniv.oblivion_ugraph in
+ match hyps_pat with
+ he::(_::_ as tl) ->
+ PET.apply_tactic
+ (T.then_
+ (rewrite_tac ~direction
+ ~pattern:(None,[he],None) equality)
+ (rewrite_tac ~direction ~pattern:(None,tl,concl_pat)
+ (S.lift 1 equality))
+ ) status
+ | [_] as hyps_pat when concl_pat <> None ->
+ PET.apply_tactic
+ (T.then_
+ (rewrite_tac ~direction
+ ~pattern:(None,hyps_pat,None) equality)
+ (rewrite_tac ~direction ~pattern:(None,[],concl_pat)
+ (S.lift 1 equality))
+ ) status
+ | _ ->
+ let arg,dir2,tac,concl_pat,gty =
+ match hyps_pat with
+ [] -> None,true,(fun ~term _ -> P.exact_tac term),concl_pat,gty
+ | [name,pat] ->
+ let rec find_hyp n =
+ function
+ [] -> assert false
+ | Some (Cic.Name s,Cic.Decl ty)::_ when name = s ->
+ Cic.Rel n, S.lift n ty
+ | Some (Cic.Name s,Cic.Def _)::_ when name = s -> assert false (*CSC: not implemented yet! But does this make any sense?*)
+ | _::tl -> find_hyp (n+1) tl
+ in
+ let arg,gty = find_hyp 1 context in
+ let dummy = "dummy" in
+ Some arg,false,
+ (fun ~term typ ->
+ T.seq
+ ~tactics:
+ [PESR.rename [name] [dummy];
+ P.letin_tac
+ ~mk_fresh_name_callback:(fun _ _ _ ~typ -> Cic.Name name) term;
+ PESR.clearbody name;
+ ReductionTactics.change_tac
+ ~pattern:
+ (None,[name,Cic.Implicit (Some `Hole)], None)
+ (ProofEngineTypes.const_lazy_term typ);
+ PESR.clear [dummy]
+ ]),
+ Some pat,gty
+ | _::_ -> assert false
+ in
+ let if_right_to_left do_not_change a b =
+ match direction with
+ | `RightToLeft -> if do_not_change then a else b
+ | `LeftToRight -> if do_not_change then b else a
+ in
+ let ty_eq,ugraph =
+ CicTypeChecker.type_of_aux' metasenv context equality
+ CicUniv.empty_ugraph in
+ let (ty_eq,metasenv',arguments,fresh_meta) =
+ TermUtil.saturate_term
+ (ProofEngineHelpers.new_meta_of_proof proof) metasenv context ty_eq 0 in
+ let equality =
+ if List.length arguments = 0 then
+ equality
+ else
+ C.Appl (equality :: arguments) in
+ (* t1x is t2 if we are rewriting in an hypothesis *)
+ let eq_ind, ty, t1, t2, t1x =
+ match ty_eq with
+ | C.Appl [C.MutInd (uri, 0, []); ty; t1; t2]
+ when LibraryObjects.is_eq_URI uri ->
+ let ind_uri =
+ match gsort with
+ C.Sort C.Prop ->
+ if_right_to_left dir2
+ LibraryObjects.eq_ind_URI LibraryObjects.eq_ind_r_URI
+ | C.Sort C.Set ->
+ if_right_to_left dir2
+ LibraryObjects.eq_rec_URI LibraryObjects.eq_rec_r_URI
+ | _ ->
+ if_right_to_left dir2
+ LibraryObjects.eq_rect_URI LibraryObjects.eq_rect_r_URI
+ in
+ let eq_ind = C.Const (ind_uri uri,[]) in
+ if dir2 then
+ if_right_to_left true (eq_ind,ty,t2,t1,t2) (eq_ind,ty,t1,t2,t1)
+ else
+ if_right_to_left true (eq_ind,ty,t1,t2,t2) (eq_ind,ty,t2,t1,t1)
+ | _ -> raise (PET.Fail (lazy "Rewrite: argument is not a proof of an equality")) in
+ (* now we always do as if direction was `LeftToRight *)
+ let fresh_name =
+ FreshNamesGenerator.mk_fresh_name
+ ~subst:[] metasenv' context C.Anonymous ~typ:ty in
+ let lifted_t1 = S.lift 1 t1x in
+ let lifted_gty = S.lift 1 gty in
+ let lifted_conjecture =
+ metano,(Some (fresh_name,Cic.Decl ty))::context,lifted_gty in
+ let lifted_pattern =
+ let lifted_concl_pat =
+ match concl_pat with
+ | None -> None
+ | Some term -> Some (S.lift 1 term) in
+ Some (fun c m u ->
+ let distance = pred (List.length c - List.length context) in
+ S.lift distance lifted_t1, m, u),[],lifted_concl_pat
+ in
+ let subst,metasenv',ugraph,_,selected_terms_with_context =
+ ProofEngineHelpers.select
+ ~metasenv:metasenv' ~ugraph ~conjecture:lifted_conjecture
+ ~pattern:lifted_pattern in
+ let metasenv' = CicMetaSubst.apply_subst_metasenv subst metasenv' in
+ let what,with_what =
+ (* Note: Rel 1 does not live in the context context_of_t *)
+ (* The replace_lifting_csc 0 function will take care of lifting it *)
+ (* to context_of_t *)
+ List.fold_right
+ (fun (context_of_t,t) (l1,l2) -> t::l1, Cic.Rel 1::l2)
+ selected_terms_with_context ([],[]) in
+ let t1 = CicMetaSubst.apply_subst subst t1 in
+ let t2 = CicMetaSubst.apply_subst subst t2 in
+ let ty = CicMetaSubst.apply_subst subst ty in
+ let pbo = CicMetaSubst.apply_subst subst pbo in
+ let pty = CicMetaSubst.apply_subst subst pty in
+ let equality = CicMetaSubst.apply_subst subst equality in
+ let abstr_gty =
+ ProofEngineReduction.replace_lifting_csc 0
+ ~equality:(==) ~what ~with_what:with_what ~where:lifted_gty in
+ if lifted_gty = abstr_gty then
+ raise (ProofEngineTypes.Fail (lazy "nothing to do"));
+ let abstr_gty = CicMetaSubst.apply_subst subst abstr_gty in
+ let pred = C.Lambda (fresh_name, ty, abstr_gty) in
+ (* The argument is either a meta if we are rewriting in the conclusion
+ or the hypothesis if we are rewriting in an hypothesis *)
+ let metasenv',arg,newtyp =
+ match arg with
+ None ->
+ let gty' = S.subst t2 abstr_gty in
+ let irl =
+ CicMkImplicit.identity_relocation_list_for_metavariable context in
+ let metasenv' = (fresh_meta,context,gty')::metasenv' in
+ metasenv', C.Meta (fresh_meta,irl), Cic.Rel (-1) (* dummy term, never used *)
+ | Some arg ->
+ let gty' = S.subst t1 abstr_gty in
+ metasenv',arg,gty'
+ in
+ let exact_proof =
+ C.Appl [eq_ind ; ty ; t2 ; pred ; arg ; t1 ;equality]
+ in
+ try
+ let (proof',goals) =
+ PET.apply_tactic
+ (tac ~term:exact_proof newtyp) ((curi,metasenv',_subst,pbo,pty, attrs),goal)
+ in
+ let goals =
+ goals@(ProofEngineHelpers.compare_metasenvs ~oldmetasenv:metasenv
+ ~newmetasenv:metasenv')
+ in
+ (proof',goals)
+ with (* FG: this should be PET.Fail _ *)
+ TC.TypeCheckerFailure _ ->
+ let msg = lazy "rewrite: nothing to rewrite" in
+ raise (PET.Fail msg)
+ in
+ PET.mk_tactic _rewrite_tac
+
+let rewrite_tac ~direction ~pattern equality names =
+ let _, hyps_pat, _ = pattern in
+ let froms = List.map fst hyps_pat in
+ let start = rewrite_tac ~direction ~pattern equality in
+ let continuation = PESR.rename ~froms ~tos:names in
+ if names = [] then start else T.then_ ~start ~continuation
+
+let rewrite_simpl_tac ~direction ~pattern equality names =
+ T.then_
+ ~start:(rewrite_tac ~direction ~pattern equality names)
+ ~continuation:
+ (ReductionTactics.simpl_tac
+ ~pattern:(ProofEngineTypes.conclusion_pattern None))
+
+
+let replace_tac ~(pattern: ProofEngineTypes.lazy_pattern) ~with_what =
+ let replace_tac ~(pattern: ProofEngineTypes.lazy_pattern) ~with_what status =
+ let _wanted, hyps_pat, concl_pat = pattern in
+ let (proof, goal) = status in
+ let uri,metasenv,_subst,pbo,pty, attrs = proof in
+ let (_,context,ty) as conjecture = CicUtil.lookup_meta goal metasenv in
+ assert (hyps_pat = []); (*CSC: not implemented yet *)
+ let eq_URI =
+ match LibraryObjects.eq_URI () with
+ Some uri -> uri
+ | None -> raise (ProofEngineTypes.Fail (lazy "You need to register the default equality first. Please use the \"default\" command"))
+ in
+ let context_len = List.length context in
+ let subst,metasenv,u,_,selected_terms_with_context =
+ ProofEngineHelpers.select ~metasenv ~ugraph:CicUniv.empty_ugraph
+ ~conjecture ~pattern in
+ let metasenv = CicMetaSubst.apply_subst_metasenv subst metasenv in
+ let with_what, metasenv, u = with_what context metasenv u in
+ let with_what = CicMetaSubst.apply_subst subst with_what in
+ let pbo = CicMetaSubst.apply_subst subst pbo in
+ let pty = CicMetaSubst.apply_subst subst pty in
+ let status = (uri,metasenv,_subst,pbo,pty, attrs),goal in
+ let ty_of_with_what,u =
+ CicTypeChecker.type_of_aux'
+ metasenv context with_what CicUniv.empty_ugraph in
+ let whats =
+ match selected_terms_with_context with
+ [] -> raise (ProofEngineTypes.Fail (lazy "Replace: no term selected"))
+ | l ->
+ List.map
+ (fun (context_of_t,t) ->
+ let t_in_context =
+ try
+ let context_of_t_len = List.length context_of_t in
+ if context_of_t_len = context_len then t
+ else
+ (let t_in_context,subst,metasenv' =
+ CicMetaSubst.delift_rels [] metasenv
+ (context_of_t_len - context_len) t
+ in
+ assert (subst = []);
+ assert (metasenv = metasenv');
+ t_in_context)
+ with
+ CicMetaSubst.DeliftingARelWouldCaptureAFreeVariable ->
+ (*CSC: we could implement something stronger by completely changing
+ the semantics of the tactic *)
+ raise (ProofEngineTypes.Fail
+ (lazy "Replace: one of the selected terms is not closed")) in
+ let ty_of_t_in_context,u = (* TASSI: FIXME *)
+ CicTypeChecker.type_of_aux' metasenv context t_in_context
+ CicUniv.empty_ugraph in
+ let b,u = CicReduction.are_convertible ~metasenv context
+ ty_of_with_what ty_of_t_in_context u in
+ if b then
+ let concl_pat_for_t = ProofEngineHelpers.pattern_of ~term:ty [t] in
+ let pattern_for_t = None,[],Some concl_pat_for_t in
+ t_in_context,pattern_for_t
+ else
+ raise
+ (ProofEngineTypes.Fail
+ (lazy "Replace: one of the selected terms and the term to be replaced with have not convertible types"))
+ ) l in
+ let rec aux n whats (status : ProofEngineTypes.status) =
+ match whats with
+ [] -> ProofEngineTypes.apply_tactic T.id_tac status
+ | (what,lazy_pattern)::tl ->
+ let what = S.lift n what in
+ let with_what = S.lift n with_what in
+ let ty_of_with_what = S.lift n ty_of_with_what in
+ ProofEngineTypes.apply_tactic
+ (T.thens
+ ~start:(
+ P.cut_tac
+ (C.Appl [
+ (C.MutInd (eq_URI, 0, [])) ;
+ ty_of_with_what ;
+ what ;
+ with_what]))
+ ~continuations:[
+ T.then_
+ ~start:(
+ rewrite_tac ~direction:`LeftToRight ~pattern:lazy_pattern (C.Rel 1) [])
+ ~continuation:(
+ T.then_
+ ~start:(
+ ProofEngineTypes.mk_tactic
+ (function ((proof,goal) as status) ->
+ let _,metasenv,_subst,_,_, _ = proof in
+ let _,context,_ = CicUtil.lookup_meta goal metasenv in
+ let hyps =
+ try
+ match List.hd context with
+ Some (Cic.Name name,_) -> [name]
+ | _ -> assert false
+ with (Failure "hd") -> assert false
+ in
+ ProofEngineTypes.apply_tactic
+ (PESR.clear ~hyps) status))
+ ~continuation:(aux_tac (n + 1) tl));
+ T.id_tac])
+ status
+ and aux_tac n tl = ProofEngineTypes.mk_tactic (aux n tl) in
+ aux 0 whats (status : ProofEngineTypes.status)
+ in
+ ProofEngineTypes.mk_tactic (replace_tac ~pattern ~with_what)
+;;
+
+
+(* All these tacs do is applying the right constructor/theorem *)
+
+let reflexivity_tac =
+ IntroductionTactics.constructor_tac ~n:1
+;;
+
+let symmetry_tac =
+ let symmetry_tac (proof, goal) =
+ let (_,metasenv,_subst,_,_, _) = proof in
+ let metano,context,ty = CicUtil.lookup_meta goal metasenv in
+ match (R.whd context ty) with
+ (C.Appl [(C.MutInd (uri, 0, [])); _; _; _])
+ when LibraryObjects.is_eq_URI uri ->
+ ProofEngineTypes.apply_tactic
+ (PrimitiveTactics.apply_tac
+ ~term: (C.Const (LibraryObjects.sym_eq_URI uri, [])))
+ (proof,goal)
+
+ | _ -> raise (ProofEngineTypes.Fail (lazy "Symmetry failed"))
+ in
+ ProofEngineTypes.mk_tactic symmetry_tac
+;;
+
+let transitivity_tac ~term =
+ let transitivity_tac ~term status =
+ let (proof, goal) = status in
+ let (_,metasenv,_subst,_,_, _) = proof in
+ let metano,context,ty = CicUtil.lookup_meta goal metasenv in
+ match (R.whd context ty) with
+ (C.Appl [(C.MutInd (uri, 0, [])); _; _; _])
+ when LibraryObjects.is_eq_URI uri ->
+ ProofEngineTypes.apply_tactic
+ (T.thens
+ ~start:(PrimitiveTactics.apply_tac
+ ~term: (C.Const (LibraryObjects.trans_eq_URI uri, [])))
+ ~continuations:
+ [PrimitiveTactics.exact_tac ~term ; T.id_tac ; T.id_tac])
+ status
+
+ | _ -> raise (ProofEngineTypes.Fail (lazy "Transitivity failed"))
+ in
+ ProofEngineTypes.mk_tactic (transitivity_tac ~term)
+;;
+