X-Git-Url: http://matita.cs.unibo.it/gitweb/?a=blobdiff_plain;f=helm%2Fsoftware%2Fcomponents%2Ftactics%2FdiscriminationTactics.ml;h=9d83ad595e8af2dfa6712afcfb04b0415f6fb7ae;hb=58c0db9bcf83591115445a538bee028d3260fdf7;hp=69739a4b0ccd1f70a128c085b39914b720c3fcf4;hpb=1e461f3fb714667cf97e593eef48781b0f2e9b7d;p=helm.git diff --git a/helm/software/components/tactics/discriminationTactics.ml b/helm/software/components/tactics/discriminationTactics.ml index 69739a4b0..9d83ad595 100644 --- a/helm/software/components/tactics/discriminationTactics.ml +++ b/helm/software/components/tactics/discriminationTactics.ml @@ -25,291 +25,15 @@ (* $Id$ *) -let debug_print = fun _ -> () - -let rec injection_tac ~first_time ~term ~liftno ~continuation = - let injection_tac ~term status = - let (proof, goal) = status in - let module C = Cic in - let module U = UriManager in - let module P = PrimitiveTactics in - let module T = Tacticals in - let _,metasenv,_,_ = proof in - let _,context,_ = CicUtil.lookup_meta goal metasenv in - let term = CicSubstitution.lift liftno term in - let termty,_ = (* TASSI: FIXME *) - CicTypeChecker.type_of_aux' metasenv context term CicUniv.empty_ugraph - in - ProofEngineTypes.apply_tactic - (match termty with - (C.Appl [(C.MutInd (equri, 0, [])) ; tty ; t1 ; t2]) - when LibraryObjects.is_eq_URI equri -> - begin - match tty with - (C.MutInd (turi,typeno,exp_named_subst)) - | (C.Appl (C.MutInd (turi,typeno,exp_named_subst)::_)) -> - begin - match t1,t2 with - ((C.MutConstruct (uri1,typeno1,consno1,exp_named_subst1)), - (C.MutConstruct (uri2,typeno2,consno2,exp_named_subst2))) - when (uri1 = uri2) && (typeno1 = typeno2) && - (consno1 = consno2) && - (exp_named_subst1 = exp_named_subst2) - -> - if first_time then - raise - (ProofEngineTypes.Fail (lazy "Injection: nothing to do")) - else - continuation ~liftno - | C.Appl - ((C.MutConstruct - (uri1,typeno1,consno1,exp_named_subst1))::applist1), - C.Appl - ((C.MutConstruct - (uri2,typeno2,consno2,exp_named_subst2))::applist2) - when (uri1 = uri2) && (typeno1 = typeno2) && - (consno1 = consno2) && - (exp_named_subst1 = exp_named_subst2) - -> - let rec traverse_list i l1 l2 = - match l1,l2 with - [],[] -> - if first_time then - continuation - else - (match term with - C.Rel n -> - (match List.nth context (n-1) with - Some (C.Name id,_) -> - fun ~liftno -> - T.then_ - ~start: - (ProofEngineStructuralRules.clear - ~hyps:[id]) - ~continuation:(continuation ~liftno) - | _ -> assert false) - | _ -> assert false) - | hd1::tl1,hd2::tl2 -> - if - fst - (CicReduction.are_convertible ~metasenv - context hd1 hd2 CicUniv.empty_ugraph) - then - traverse_list (i+1) tl1 tl2 - else - injection1_tac ~i ~term - ~continuation:(traverse_list (i+1) tl1 tl2) - | _ -> raise (ProofEngineTypes.Fail (lazy "Discriminate: i 2 termini hanno in testa lo stesso costruttore, ma applicato a un numero diverso di termini. possibile???")) - in - traverse_list 1 applist1 applist2 ~liftno - | ((C.MutConstruct (uri1,typeno1,consno1,exp_named_subst1)), - (C.MutConstruct (uri2,typeno2,consno2,exp_named_subst2))) - | ((C.MutConstruct (uri1,typeno1,consno1,exp_named_subst1)), - (C.Appl ((C.MutConstruct (uri2,typeno2,consno2,exp_named_subst2))::_))) - | ((C.Appl ((C.MutConstruct (uri1,typeno1,consno1,exp_named_subst1))::_)), - (C.MutConstruct (uri2,typeno2,consno2,exp_named_subst2))) - | ((C.Appl ((C.MutConstruct (uri1,typeno1,consno1,exp_named_subst1))::_)), - (C.Appl ((C.MutConstruct (uri2,typeno2,consno2,exp_named_subst2))::_))) - when (consno1 <> consno2) || (exp_named_subst1 <> exp_named_subst2) -> - raise (ProofEngineTypes.Fail (lazy "Injection: not a projectable equality but a discriminable one")) - | _ -> - if first_time then - raise (ProofEngineTypes.Fail (lazy "Injection: not a projectable equality")) - else - continuation ~liftno - end - | _ -> - if first_time then - raise (ProofEngineTypes.Fail (lazy "Injection: not a projectable equality")) - else - continuation ~liftno - end - | _ -> raise (ProofEngineTypes.Fail (lazy "Injection: not an equation")) - ) status - in - ProofEngineTypes.mk_tactic (injection_tac ~term) - -and injection1_tac ~term ~i ~liftno ~continuation = - let injection1_tac ~term ~i status = - let (proof, goal) = status in - (* precondizione: t1 e t2 hanno in testa lo stesso costruttore ma differiscono (o potrebbero differire?) nell'i-esimo parametro del costruttore *) - let module C = Cic in - let module S = CicSubstitution in - let module U = UriManager in - let module P = PrimitiveTactics in - let module T = Tacticals in - let term = CicSubstitution.lift liftno term in - let _,metasenv,_,_ = proof in - let _,context,_ = CicUtil.lookup_meta goal metasenv in - let termty,_ = (* TASSI: FIXME *) - CicTypeChecker.type_of_aux' metasenv context term CicUniv.empty_ugraph - in - match termty with (* an equality *) - (C.Appl [(C.MutInd (equri, 0, [])) ; tty ; t1 ; t2]) - when LibraryObjects.is_eq_URI equri -> ( - match tty with (* some inductive type *) - (C.MutInd (turi,typeno,exp_named_subst)) - | (C.Appl (C.MutInd (turi,typeno,exp_named_subst)::_)) -> - let t1',t2',consno = (* sono i due sottotermini che differiscono *) - match t1,t2 with - ((C.Appl ((C.MutConstruct (uri1,typeno1,consno1,exp_named_subst1))::applist1)), - (C.Appl ((C.MutConstruct (uri2,typeno2,consno2,exp_named_subst2))::applist2))) - when (uri1 = uri2) && (typeno1 = typeno2) && (consno1 = consno2) && (exp_named_subst1 = exp_named_subst2) -> (* controllo ridondante *) - (List.nth applist1 (i-1)),(List.nth applist2 (i-1)),consno2 - | _ -> assert false - in - let tty',_ = - CicTypeChecker.type_of_aux' metasenv context t1' - CicUniv.empty_ugraph in - let patterns,outtype = - match - fst (CicEnvironment.get_obj CicUniv.empty_ugraph turi) - with - C.InductiveDefinition (ind_type_list,_,paramsno,_)-> - let _,_,_,constructor_list = - List.nth ind_type_list typeno in - let i_constr_id,_ = - List.nth constructor_list (consno - 1) in - let seed = ref 0 in - let patterns = - List.map - (function (id,cty) -> - let reduced_cty = CicReduction.whd context cty in - let rec aux t k = - match t with - C.Prod (_,_,target) when k <= paramsno -> - aux target (k+1) - | C.Prod (binder,source,target) when k > paramsno -> - let binder' = - match binder with - C.Name _ -> binder - | C.Anonymous -> - C.Name - (incr seed; "y" ^ string_of_int !seed) - in - C.Lambda (binder',source,(aux target (k+1))) - | _ -> - let nr_param_constr = k - 1 - paramsno in - if id = i_constr_id - then C.Rel (k - i) - else S.lift (nr_param_constr + 1) t1' (* + 1 per liftare anche il lambda aggiunto esternamente al case *) - in aux reduced_cty 1 - ) constructor_list in - let outtype = - let seed = ref 0 in - let rec to_lambdas te head = - match CicReduction.whd context te with - | C.Prod (binder,so,ta) -> - let binder' = - match binder with - C.Name _ -> binder - | C.Anonymous -> - C.Name (incr seed; "d" ^ string_of_int !seed) - in - C.Lambda (binder',so,to_lambdas ta head) - | _ -> head in - let rec skip_prods n te = - match n, CicReduction.whd context te with - 0, _ -> te - | n, C.Prod (_,_,ta) -> skip_prods (n - 1) ta - | _, _ -> assert false - in - let abstracted_tty = - match CicSubstitution.lift (paramsno + 1) tty with - C.MutInd _ as tty' -> tty' - | C.Appl l -> - let keep,abstract = - HExtlib.split_nth (paramsno +1) l in - let rec mk_rels = - function - 0 -> [] - | n -> C.Rel n :: (mk_rels (n - 1)) - in - C.Appl (keep@mk_rels (List.length abstract)) - | _ -> assert false - in - match ind_type_list with - [] -> assert false - | (_,_,ty,_)::_ -> - to_lambdas (skip_prods paramsno ty) - (C.Lambda (C.Name "x", abstracted_tty, - S.lift (2+paramsno) tty')) - in - patterns,outtype - | _ -> raise (ProofEngineTypes.Fail (lazy "Discriminate: object is not an Inductive Definition: it's imposible")) - in - ProofEngineTypes.apply_tactic - (T.thens - ~start: - (P.cut_tac - (C.Appl [C.MutInd (equri,0,[]) ; tty' ; t1' ; t2'])) - ~continuations: - [ injection_tac ~first_time:false ~liftno:0 - ~term:(C.Rel 1) - (* here I need to lift all the continuations by 1; - since I am setting back liftno to 0, I actually - need to lift all the continuations by liftno + 1 *) - ~continuation: - (fun ~liftno:x -> - continuation ~liftno:(liftno + 1 + x)) ; - T.then_ - ~start:(ProofEngineTypes.mk_tactic - (fun status -> - let (proof, goal) = status in - let _,metasenv,_,_ = proof in - let _,context,gty = - CicUtil.lookup_meta goal metasenv - in - let new_t1' = - match gty with - (C.Appl (C.MutInd (_,_,_)::arglist)) -> - List.nth arglist 1 - | _ -> - raise - (ProofEngineTypes.Fail - (lazy - "Injection: goal after cut is not correct")) - in - ProofEngineTypes.apply_tactic - (ReductionTactics.change_tac - ~pattern:(ProofEngineTypes.conclusion_pattern - (Some new_t1')) - (fun _ m u -> - C.Appl [ - C.Lambda - (C.Name "x", - tty, - C.MutCase - (turi,typeno,outtype,C.Rel 1,patterns)) ; - t1], - m, u)) - status - )) - ~continuation: - (T.then_ - ~start: - (EqualityTactics.rewrite_simpl_tac - ~direction:`LeftToRight - ~pattern:(ProofEngineTypes.conclusion_pattern None) - term) - ~continuation:EqualityTactics.reflexivity_tac) - ]) - status - | _ -> raise (ProofEngineTypes.Fail (lazy "Injection: not an equality over elements of an inductive type")) - ) - | _ -> raise (ProofEngineTypes.Fail (lazy "Injection: not an equality")) - in - ProofEngineTypes.mk_tactic (injection1_tac ~term ~i) -;; - -let injection_tac = - injection_tac ~first_time:true ~liftno:0 ~continuation:(fun ~liftno -> Tacticals.id_tac) +let debug = false +let debug_print = + if debug then (fun x -> prerr_endline (Lazy.force x)) else (fun _ -> ()) ;; (* term ha tipo t1=t2; funziona solo se t1 e t2 hanno in testa costruttori diversi *) -let discriminate'_tac ~term = +let discriminate_tac ~term = let module C = Cic in let module U = UriManager in let module P = PrimitiveTactics in @@ -421,7 +145,7 @@ let discriminate'_tac ~term = in let discriminate'_tac ~term status = let (proof, goal) = status in - let _,metasenv,_,_ = proof in + let _,metasenv,_subst,_,_, _ = proof in let _,context,_ = CicUtil.lookup_meta goal metasenv in let termty,_ = CicTypeChecker.type_of_aux' metasenv context term CicUniv.empty_ugraph @@ -465,19 +189,330 @@ let discriminate'_tac ~term = (EqualityTactics.rewrite_simpl_tac ~direction:`RightToLeft ~pattern:(ProofEngineTypes.conclusion_pattern None) - term) + term []) ~continuation: (IntroductionTactics.constructor_tac ~n:1)))) status | _ -> fail "not an equality" in ProofEngineTypes.mk_tactic (discriminate'_tac ~term) +;; + +let exn_nonproj = + ProofEngineTypes.Fail (lazy "Injection: not a projectable equality");; +let exn_noneq = + ProofEngineTypes.Fail (lazy "Injection: not an equality");; +let exn_nothingtodo = + ProofEngineTypes.Fail (lazy "Nothing to do");; +let exn_discrnonind = + ProofEngineTypes.Fail (lazy "Discriminate: object is not an Inductive Definition: it's imposible");; +let exn_injwronggoal = + ProofEngineTypes.Fail (lazy "Injection: goal after cut is not correct");; +let exn_noneqind = + ProofEngineTypes.Fail (lazy "Injection: not an equality over elements of an inductive type");; + +let pp ctx t = + let names = List.map (function Some (n,_) -> Some n | None -> None) ctx in + CicPp.pp t names +;; + +let rec injection_tac ~first_time ~term ~liftno ~continuation = + let module C = Cic in + let module CR = CicReduction in + let module U = UriManager in + let module P = PrimitiveTactics in + let module T = Tacticals in + let module PST = ProofEngineStructuralRules in + let module PET = ProofEngineTypes in + let are_convertible hd1 hd2 metasenv context = + fst (CR.are_convertible ~metasenv context hd1 hd2 CicUniv.empty_ugraph) + in + let injection_tac ~term status = + let (proof, goal) = status in + let _,metasenv,_subst, _,_, _ = proof in + let _,context,_ = CicUtil.lookup_meta goal metasenv in + let term = CicSubstitution.lift liftno term in + let termty,_ = + CicTypeChecker.type_of_aux' metasenv context term CicUniv.empty_ugraph + in + debug_print (lazy ("\ninjection su: " ^ pp context termty)); + let tac = + match termty with + | C.Appl [(C.MutInd (equri, 0, [])) ; tty ; t1 ; t2] + when LibraryObjects.is_eq_URI equri -> begin + match (CicReduction.whd ~delta:true context tty) with + | C.MutInd (turi,typeno,ens) + | C.Appl (C.MutInd (turi,typeno,ens)::_) -> begin + match t1,t2 with + | C.MutConstruct (uri1,typeno1,consno1,ens1), + C.MutConstruct (uri2,typeno2,consno2,ens2) + when (uri1 = uri2) && (typeno1 = typeno2) && + (consno1 = consno2) && (ens1 = ens2) -> + if first_time then raise exn_nothingtodo + else continuation ~liftno + | C.Appl ((C.MutConstruct (uri1,typeno1,consno1,ens1))::applist1), + C.Appl ((C.MutConstruct (uri2,typeno2,consno2,ens2))::applist2) + when (uri1 = uri2) && (typeno1 = typeno2) && + (consno1 = consno2) && (ens1 = ens2) -> + let rec traverse_list i l1 l2 = + match l1,l2 with + | [],[] when first_time -> continuation + | [],[] -> begin + match term with + | C.Rel n -> begin + match List.nth context (n-1) with + | Some (C.Name id,_) -> + fun ~liftno -> + T.then_ ~start:(PST.clear ~hyps:[id]) + ~continuation:(continuation ~liftno) + | _ -> assert false + end + | _ -> assert false + end + | hd1::tl1,hd2::tl2 -> + if are_convertible hd1 hd2 metasenv context then + traverse_list (i+1) tl1 tl2 + else + injection1_tac ~i ~term + ~continuation:(traverse_list (i+1) tl1 tl2) + | _ -> assert false + (* i 2 termini hanno in testa lo stesso costruttore, + * ma applicato a un numero diverso di termini *) + in + traverse_list 1 applist1 applist2 ~liftno + | C.MutConstruct (uri1,typeno1,consno1,ens1), + C.MutConstruct (uri2,typeno2,consno2,ens2) + | C.MutConstruct (uri1,typeno1,consno1,ens1), + C.Appl ((C.MutConstruct (uri2,typeno2,consno2,ens2))::_) + | C.Appl ((C.MutConstruct (uri1,typeno1,consno1,ens1))::_), + C.MutConstruct (uri2,typeno2,consno2,ens2) + | C.Appl ((C.MutConstruct (uri1,typeno1,consno1,ens1))::_), + C.Appl ((C.MutConstruct (uri2,typeno2,consno2,ens2))::_) + when (consno1 <> consno2) || (ens1 <> ens2) -> + discriminate_tac ~term + | _ when not first_time -> continuation ~liftno + | _ (* when first_time *) -> + match term with + | Cic.Rel i -> + let name = + match List.nth context (i-1) with + | Some (Cic.Name s, Cic.Def _) -> s + | Some (Cic.Name s, Cic.Decl _) -> s + | _ -> assert false + in + Tacticals.then_ + ~start:(ReductionTactics.simpl_tac + ~pattern:(None,[name,Cic.Implicit (Some `Hole)],None)) + ~continuation:(injection_tac ~first_time:false ~term ~liftno + ~continuation) + | _ -> raise exn_nonproj + end + | _ when not first_time -> continuation ~liftno + | _ (* when first_time *) -> raise exn_nonproj + end + | _ -> raise exn_nonproj + in + PET.apply_tactic tac status + in + PET.mk_tactic (injection_tac ~term) -let discriminate_tac ~term = - let discriminate_tac ~term status = - ProofEngineTypes.apply_tactic - (Tacticals.then_ - ~start:(* (injection_tac ~term) *) Tacticals.id_tac - ~continuation:(discriminate'_tac ~term)) (* NOOO!!! non term ma una (qualunque) delle nuove hyp introdotte da inject *) - status +and injection1_tac ~term ~i ~liftno ~continuation = + let module C = Cic in + let module CTC = CicTypeChecker in + let module CU = CicUniv in + let module S = CicSubstitution in + let module U = UriManager in + let module P = PrimitiveTactics in + let module PET = ProofEngineTypes in + let module T = Tacticals in + let give_name seed = function + | C.Name _ as name -> name + | C.Anonymous -> C.Name (incr seed; "y" ^ string_of_int !seed) in - ProofEngineTypes.mk_tactic (discriminate_tac ~term) + let rec mk_rels = function | 0 -> [] | n -> C.Rel n :: (mk_rels (n - 1)) in + let injection1_tac ~term ~i status = + let (proof, goal) = status in + (* precondizione: t1 e t2 hanno in testa lo stesso costruttore ma + * differiscono (o potrebbero differire?) nell'i-esimo parametro + * del costruttore *) + let term = CicSubstitution.lift liftno term in + let _,metasenv,_subst,_,_, _ = proof in + let _,context,_ = CicUtil.lookup_meta goal metasenv in + let termty,_ = + CicTypeChecker.type_of_aux' metasenv context term CicUniv.empty_ugraph + in + debug_print (lazy ("\ninjection1 su : " ^ pp context termty)); + match termty with (* an equality *) + | C.Appl [(C.MutInd (equri, 0, [])) ; tty ; t1 ; t2] + when LibraryObjects.is_eq_URI equri -> + let turi,typeno,ens,params = + match tty with (* some inductive type *) + | C.MutInd (turi,typeno,ens) -> turi,typeno,ens,[] + | C.Appl (C.MutInd (turi,typeno,ens)::params) -> turi,typeno,ens,params + | _ -> raise exn_noneqind + in + let t1',t2',consno = (* sono i due sottotermini che differiscono *) + match t1,t2 with + | C.Appl ((C.MutConstruct (uri1,typeno1,consno1,ens1))::applist1), + C.Appl ((C.MutConstruct (uri2,typeno2,consno2,ens2))::applist2) + when (uri1 = uri2) && (typeno1 = typeno2) && + (consno1 = consno2) && (ens1 = ens2) -> + (* controllo ridondante *) + List.nth applist1 (i-1),List.nth applist2 (i-1),consno2 + | _ -> assert false + in + let tty',_ = CTC.type_of_aux' metasenv context t1' CU.empty_ugraph in + let patterns,outtype = + match fst (CicEnvironment.get_obj CicUniv.empty_ugraph turi) with + | C.InductiveDefinition (ind_type_list,_,paramsno,_)-> + let left_params, right_params = HExtlib.split_nth paramsno params in + let _,_,_,constructor_list = List.nth ind_type_list typeno in + let i_constr_id,_ = List.nth constructor_list (consno - 1) in + let patterns = + let seed = ref 0 in + List.map + (function (id,cty) -> + let reduced_cty = CicReduction.whd context cty in + let rec aux k = function + | C.Prod (_,_,tgt) when k <= paramsno -> + let left = List.nth left_params (k-1) in + aux (k+1) (CicSubstitution.subst left tgt) + | C.Prod (binder,source,target) when k > paramsno -> + let binder' = give_name seed binder in + C.Lambda (binder',source,(aux (k+1) target)) + | _ -> + let nr_param_constr = k - paramsno - 1 in + if id = i_constr_id then C.Rel (k - i) + else S.lift nr_param_constr t1' + (* + 1 per liftare anche il lambda aggiunto + * esternamente al case *) + in CicSubstitution.lift 1 (aux 1 reduced_cty)) + constructor_list + in + (* this code should be taken from cases_tac *) + let outtype = + let seed = ref 0 in + let rec to_lambdas te head = + match CicReduction.whd context te with + | C.Prod (binder,so,ta) -> + let binder' = give_name seed binder in + C.Lambda (binder',so,to_lambdas ta head) + | _ -> head + in + let rec skip_prods params te = + match params, CicReduction.whd context te with + | [], _ -> te + | left::tl, C.Prod (_,_,ta) -> + skip_prods tl (CicSubstitution.subst left ta) + | _, _ -> assert false + in + let abstracted_tty = + let tty = + List.fold_left (fun x y -> CicSubstitution.subst y x) tty left_params + in + (* non lift, ma subst coi left! *) + match S.lift 1 tty with + | C.MutInd _ as tty' -> tty' + | C.Appl l -> + let keep,abstract = HExtlib.split_nth (paramsno +1) l in + let keep = List.map (S.lift paramsno) keep in + C.Appl (keep@mk_rels (List.length abstract)) + | _ -> assert false + in + match ind_type_list with + | [] -> assert false + | (_,_,ty,_)::_ -> + (* this is in general wrong, do as in cases_tac *) + to_lambdas (skip_prods left_params ty) + (C.Lambda + (C.Name "cased", abstracted_tty, + (* here we should capture right parameters *) + (* 1 for his Lambda, one for the Lambda outside the match + * and then one for each to_lambda *) + S.lift (2+List.length right_params) tty')) + in + patterns,outtype + | _ -> raise exn_discrnonind + in + let cutted = C.Appl [C.MutInd (equri,0,[]) ; tty' ; t1' ; t2'] in + let changed = + C.Appl [ C.Lambda (C.Name "x", tty, + C.MutCase (turi,typeno,outtype,C.Rel 1,patterns)) ; t1] + in + (* check if cutted and changed are well typed and if t1' ~ changed *) + let go_on = + try + let _,g = CicTypeChecker.type_of_aux' metasenv context cutted + CicUniv.empty_ugraph + in + let _,g = CicTypeChecker.type_of_aux' metasenv context changed g in + fst (CicReduction.are_convertible ~metasenv context t1' changed g) + with + | CicTypeChecker.TypeCheckerFailure _ -> false + in + if not go_on then + PET.apply_tactic Tacticals.id_tac status + else + (debug_print (lazy ("CUT: " ^ pp context cutted)); + PET.apply_tactic + (T.thens ~start: (P.cut_tac cutted) + ~continuations: + [injection_tac ~first_time:false ~liftno:0 ~term:(C.Rel 1) + ~continuation: + (fun ~liftno:x -> continuation ~liftno:(liftno+1+x)) + (* here I need to lift all the continuations by 1; + since I am setting back liftno to 0, I actually + need to lift all the continuations by liftno + 1 *) + ;T.then_ + ~start:(PET.mk_tactic + (fun status -> + debug_print (lazy "riempo il cut"); + let (proof, goal) = status in + let _,metasenv,_subst,_,_, _ = proof in + let _,context,gty =CicUtil.lookup_meta goal metasenv in + let gty = Unshare.unshare gty in + let new_t1' = + match gty with + | (C.Appl (C.MutInd (_,_,_)::_::t::_)) -> t + | _ -> raise exn_injwronggoal + in + debug_print + (lazy ("metto questo: " ^ pp context changed)); + debug_print + (lazy ("al posto di questo: " ^ pp context new_t1')); + debug_print + (lazy ("nel goal: " ^ pp context gty)); + debug_print + (lazy ("nel contesto:\n" ^ CicPp.ppcontext context)); + debug_print + (lazy ("e poi rewrite con: "^pp context term)); + let rc = + PET.apply_tactic + (ReductionTactics.change_tac + ~pattern:(None, [], + Some (ProofEngineHelpers.pattern_of + ~term:gty [new_t1'])) + (fun _ m u -> changed,m,u)) + status + in rc + )) + ~continuation: + (T.then_ + ~start: + (EqualityTactics.rewrite_simpl_tac + ~direction:`LeftToRight + ~pattern:(PET.conclusion_pattern None) + term []) + ~continuation:EqualityTactics.reflexivity_tac) + ]) + status) + | _ -> raise exn_noneq + in + PET.mk_tactic (injection1_tac ~term ~i) +;; + +(* destruct performs either injection or discriminate *) +(* equivalent to Coq's "analyze equality" *) +let destruct_tac = + injection_tac + ~first_time:true ~liftno:0 ~continuation:(fun ~liftno -> Tacticals.id_tac) +;;