1 (* Copyright (C) 2002, HELM Team.
3 * This file is part of HELM, an Hypertextual, Electronic
4 * Library of Mathematics, developed at the Computer Science
5 * Department, University of Bologna, Italy.
7 * HELM is free software; you can redistribute it and/or
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9 * as published by the Free Software Foundation; either version 2
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13 * but WITHOUT ANY WARRANTY; without even the implied warranty of
14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15 * GNU General Public License for more details.
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19 * Foundation, Inc., 59 Temple Place - Suite 330, Boston,
22 * For details, see the HELM World-Wide-Web page,
23 * http://cs.unibo.it/helm/.
28 let rec rewrite_tac ~direction ~(pattern: ProofEngineTypes.lazy_pattern) equality =
29 let _rewrite_tac ~direction ~pattern:(wanted,hyps_pat,concl_pat) equality status
32 let module U = UriManager in
33 let module PET = ProofEngineTypes in
34 let module PER = ProofEngineReduction in
35 let module PEH = ProofEngineHelpers in
36 let module PT = PrimitiveTactics in
37 assert (wanted = None); (* this should be checked syntactically *)
38 let proof,goal = status in
39 let curi, metasenv, pbo, pty = proof in
40 let (metano,context,gty) = CicUtil.lookup_meta goal metasenv in
45 (rewrite_tac ~direction
46 ~pattern:(None,[he],None) equality)
47 (rewrite_tac ~direction ~pattern:(None,tl,concl_pat) equality)
49 | [_] as hyps_pat when concl_pat <> None ->
52 (rewrite_tac ~direction
53 ~pattern:(None,hyps_pat,None) equality)
54 (rewrite_tac ~direction ~pattern:(None,[],concl_pat) equality)
57 let arg,dir2,tac,concl_pat,gty =
59 [] -> None,true,(fun ~term _ -> PT.exact_tac term),concl_pat,gty
64 | Some (Cic.Name s,Cic.Decl ty)::_ when name = s ->
65 Cic.Rel n, CicSubstitution.lift n ty
66 | Some (Cic.Name s,Cic.Def _)::_ -> assert false (*CSC: not implemented yet! But does this make any sense?*)
67 | _::tl -> find_hyp (n+1) tl
69 let arg,gty = find_hyp 1 context in
70 let dummy = "dummy" in
75 [ProofEngineStructuralRules.rename name dummy;
77 ~mk_fresh_name_callback:(fun _ _ _ ~typ -> Cic.Name name) term;
78 ProofEngineStructuralRules.clearbody name;
79 ReductionTactics.change_tac
81 (None,[name,Cic.Implicit (Some `Hole)], None)
82 (ProofEngineTypes.const_lazy_term typ);
83 ProofEngineStructuralRules.clear dummy
86 | _::_ -> assert false
88 let if_right_to_left do_not_change a b =
90 | `RightToLeft -> if do_not_change then a else b
91 | `LeftToRight -> if do_not_change then b else a
94 CicTypeChecker.type_of_aux' metasenv context equality
95 CicUniv.empty_ugraph in
96 let (ty_eq,metasenv',arguments,fresh_meta) =
97 ProofEngineHelpers.saturate_term
98 (ProofEngineHelpers.new_meta_of_proof proof) metasenv context ty_eq 0 in
100 if List.length arguments = 0 then
103 C.Appl (equality :: arguments) in
104 (* t1x is t2 if we are rewriting in an hypothesis *)
105 let eq_ind, ty, t1, t2, t1x =
107 | C.Appl [C.MutInd (uri, 0, []); ty; t1; t2]
108 when LibraryObjects.is_eq_URI uri ->
110 if_right_to_left dir2
111 LibraryObjects.eq_ind_URI LibraryObjects.eq_ind_r_URI
113 let eq_ind = C.Const (ind_uri uri,[]) in
115 if_right_to_left true (eq_ind,ty,t2,t1,t2) (eq_ind,ty,t1,t2,t1)
117 if_right_to_left true (eq_ind,ty,t1,t2,t2) (eq_ind,ty,t2,t1,t1)
118 | _ -> raise (PET.Fail (lazy "Rewrite: argument is not a proof of an equality")) in
119 (* now we always do as if direction was `LeftToRight *)
121 FreshNamesGenerator.mk_fresh_name
122 ~subst:[] metasenv' context C.Anonymous ~typ:ty in
123 let lifted_t1 = CicSubstitution.lift 1 t1x in
124 let lifted_gty = CicSubstitution.lift 1 gty in
125 let lifted_conjecture =
126 metano,(Some (fresh_name,Cic.Decl ty))::context,lifted_gty in
128 let lifted_concl_pat =
131 | Some term -> Some (CicSubstitution.lift 1 term) in
132 Some (fun _ m u -> lifted_t1, m, u),[],lifted_concl_pat
134 let subst,metasenv',ugraph,_,selected_terms_with_context =
135 ProofEngineHelpers.select
136 ~metasenv:metasenv' ~ugraph ~conjecture:lifted_conjecture
137 ~pattern:lifted_pattern in
138 let metasenv' = CicMetaSubst.apply_subst_metasenv subst metasenv' in
140 (* Note: Rel 1 does not live in the context context_of_t *)
141 (* The replace_lifting_csc 0 function will take care of lifting it *)
142 (* to context_of_t *)
144 (fun (context_of_t,t) (l1,l2) -> t::l1, Cic.Rel 1::l2)
145 selected_terms_with_context ([],[]) in
146 let t1 = CicMetaSubst.apply_subst subst t1 in
147 let t2 = CicMetaSubst.apply_subst subst t2 in
148 let equality = CicMetaSubst.apply_subst subst equality in
150 ProofEngineReduction.replace_lifting_csc 0
151 ~equality:(==) ~what ~with_what:with_what ~where:lifted_gty in
152 let abstr_gty = CicMetaSubst.apply_subst subst abstr_gty in
153 let pred = C.Lambda (fresh_name, ty, abstr_gty) in
154 (* The argument is either a meta if we are rewriting in the conclusion
155 or the hypothesis if we are rewriting in an hypothesis *)
156 let metasenv',arg,newtyp =
159 let gty' = CicSubstitution.subst t2 abstr_gty in
161 CicMkImplicit.identity_relocation_list_for_metavariable context in
162 let metasenv' = (fresh_meta,context,gty')::metasenv' in
163 metasenv', C.Meta (fresh_meta,irl), Cic.Rel (-1) (* dummy term, never used *)
165 let gty' = CicSubstitution.subst t1 abstr_gty in
169 C.Appl [eq_ind ; ty ; t2 ; pred ; arg ; t1 ;equality]
173 (tac ~term:exact_proof newtyp) ((curi,metasenv',pbo,pty),goal)
176 goals@(ProofEngineHelpers.compare_metasenvs ~oldmetasenv:metasenv
177 ~newmetasenv:metasenv')
181 ProofEngineTypes.mk_tactic (_rewrite_tac ~direction ~pattern equality)
184 let rewrite_simpl_tac ~direction ~pattern equality =
185 let rewrite_simpl_tac ~direction ~pattern equality status =
186 ProofEngineTypes.apply_tactic
188 ~start:(rewrite_tac ~direction ~pattern equality)
190 (ReductionTactics.simpl_tac
191 ~pattern:(ProofEngineTypes.conclusion_pattern None)))
194 ProofEngineTypes.mk_tactic (rewrite_simpl_tac ~direction ~pattern equality)
197 let replace_tac ~(pattern: ProofEngineTypes.lazy_pattern) ~with_what =
198 let replace_tac ~(pattern: ProofEngineTypes.lazy_pattern) ~with_what status =
199 let _wanted, hyps_pat, concl_pat = pattern in
200 let (proof, goal) = status in
201 let module C = Cic in
202 let module U = UriManager in
203 let module P = PrimitiveTactics in
204 let module T = Tacticals in
205 let uri,metasenv,pbo,pty = proof in
206 let (_,context,ty) as conjecture = CicUtil.lookup_meta goal metasenv in
207 assert (hyps_pat = []); (*CSC: not implemented yet *)
208 let context_len = List.length context in
209 let subst,metasenv,u,_,selected_terms_with_context =
210 ProofEngineHelpers.select ~metasenv ~ugraph:CicUniv.empty_ugraph
211 ~conjecture ~pattern in
212 let metasenv = CicMetaSubst.apply_subst_metasenv subst metasenv in
213 let with_what, metasenv, u = with_what context metasenv u in
214 let with_what = CicMetaSubst.apply_subst subst with_what in
215 let pbo = CicMetaSubst.apply_subst subst pbo in
216 let pty = CicMetaSubst.apply_subst subst pty in
217 let status = (uri,metasenv,pbo,pty),goal in
218 let ty_of_with_what,u =
219 CicTypeChecker.type_of_aux'
220 metasenv context with_what CicUniv.empty_ugraph in
222 match selected_terms_with_context with
223 [] -> raise (ProofEngineTypes.Fail (lazy "Replace: no term selected"))
226 (fun (context_of_t,t) ->
229 let context_of_t_len = List.length context_of_t in
230 if context_of_t_len = context_len then t
232 (let t_in_context,subst,metasenv' =
233 CicMetaSubst.delift_rels [] metasenv
234 (context_of_t_len - context_len) t
237 assert (metasenv = metasenv');
240 CicMetaSubst.DeliftingARelWouldCaptureAFreeVariable ->
241 (*CSC: we could implement something stronger by completely changing
242 the semantics of the tactic *)
243 raise (ProofEngineTypes.Fail
244 (lazy "Replace: one of the selected terms is not closed")) in
245 let ty_of_t_in_context,u = (* TASSI: FIXME *)
246 CicTypeChecker.type_of_aux' metasenv context t_in_context
247 CicUniv.empty_ugraph in
248 let b,u = CicReduction.are_convertible ~metasenv context
249 ty_of_with_what ty_of_t_in_context u in
251 let concl_pat_for_t = ProofEngineHelpers.pattern_of ~term:ty [t] in
252 let pattern_for_t = None,[],Some concl_pat_for_t in
253 t_in_context,pattern_for_t
256 (ProofEngineTypes.Fail
257 (lazy "Replace: one of the selected terms and the term to be replaced with have not convertible types"))
259 let rec aux n whats status =
261 [] -> ProofEngineTypes.apply_tactic T.id_tac status
262 | (what,lazy_pattern)::tl ->
263 let what = CicSubstitution.lift n what in
264 let with_what = CicSubstitution.lift n with_what in
265 let ty_of_with_what = CicSubstitution.lift n ty_of_with_what in
266 ProofEngineTypes.apply_tactic
271 (C.MutInd (LibraryObjects.eq_URI (), 0, [])) ;
278 rewrite_tac ~direction:`LeftToRight ~pattern:lazy_pattern (C.Rel 1))
282 ProofEngineTypes.mk_tactic
283 (function ((proof,goal) as status) ->
284 let _,metasenv,_,_ = proof in
285 let _,context,_ = CicUtil.lookup_meta goal metasenv in
288 match List.hd context with
289 Some (Cic.Name name,_) -> name
291 with (Failure "hd") -> assert false
293 ProofEngineTypes.apply_tactic
294 (ProofEngineStructuralRules.clear ~hyp) status))
295 ~continuation:(aux_tac (n + 1) tl));
298 and aux_tac n tl = ProofEngineTypes.mk_tactic (aux n tl) in
301 ProofEngineTypes.mk_tactic (replace_tac ~pattern ~with_what)
305 (* All these tacs do is applying the right constructor/theorem *)
307 let reflexivity_tac =
308 IntroductionTactics.constructor_tac ~n:1
312 let symmetry_tac (proof, goal) =
313 let module C = Cic in
314 let module R = CicReduction in
315 let module U = UriManager in
316 let (_,metasenv,_,_) = proof in
317 let metano,context,ty = CicUtil.lookup_meta goal metasenv in
318 match (R.whd context ty) with
319 (C.Appl [(C.MutInd (uri, 0, [])); _; _; _])
320 when LibraryObjects.is_eq_URI uri ->
321 ProofEngineTypes.apply_tactic
322 (PrimitiveTactics.apply_tac
323 ~term: (C.Const (LibraryObjects.sym_eq_URI uri, [])))
326 | _ -> raise (ProofEngineTypes.Fail (lazy "Symmetry failed"))
328 ProofEngineTypes.mk_tactic symmetry_tac
331 let transitivity_tac ~term =
332 let transitivity_tac ~term status =
333 let (proof, goal) = status in
334 let module C = Cic in
335 let module R = CicReduction in
336 let module U = UriManager in
337 let module T = Tacticals in
338 let (_,metasenv,_,_) = proof in
339 let metano,context,ty = CicUtil.lookup_meta goal metasenv in
340 match (R.whd context ty) with
341 (C.Appl [(C.MutInd (uri, 0, [])); _; _; _])
342 when LibraryObjects.is_eq_URI uri ->
343 ProofEngineTypes.apply_tactic
345 ~start:(PrimitiveTactics.apply_tac
346 ~term: (C.Const (LibraryObjects.trans_eq_URI uri, [])))
348 [PrimitiveTactics.exact_tac ~term ; T.id_tac ; T.id_tac])
351 | _ -> raise (ProofEngineTypes.Fail (lazy "Transitivity failed"))
353 ProofEngineTypes.mk_tactic (transitivity_tac ~term)