X-Git-Url: http://matita.cs.unibo.it/gitweb/?a=blobdiff_plain;f=helm%2Focaml%2Ftactics%2FreductionTactics.ml;h=f5c82a9fe7da0be3f2702d90c5733a99cc3c6f4d;hb=91a095f0686ee569ba035e4e30c7d071588cb8e7;hp=c641cbf653af905c3b4689b5f4407dc6bdb6ecaa;hpb=caaca5ed51e45a023ccb1244fd5cbbb32d233e2e;p=helm.git diff --git a/helm/ocaml/tactics/reductionTactics.ml b/helm/ocaml/tactics/reductionTactics.ml index c641cbf65..f5c82a9fe 100644 --- a/helm/ocaml/tactics/reductionTactics.ml +++ b/helm/ocaml/tactics/reductionTactics.ml @@ -25,88 +25,45 @@ open ProofEngineTypes -(* -let reduction_tac ~reduction (proof,goal) = - let curi,metasenv,pbo,pty = proof in - let metano,context,ty = CicUtil.lookup_meta goal metasenv in - let new_ty = reduction context ty in - let new_metasenv = - List.map - (function - (n,_,_) when n = metano -> (metano,context,new_ty) - | _ as t -> t - ) metasenv - in - (curi,new_metasenv,pbo,pty), [metano] -;; -*) - -(* The default of term is the thesis of the goal to be prooved *) -let reduction_tac ~reduction ~pattern:(hyp_patterns,goal_pattern) (proof,goal) = +(* Note: this code is almost identical to change_tac and +* it could be unified by making the change function a callback *) +let reduction_tac ~reduction ~pattern (proof,goal) = let curi,metasenv,pbo,pty = proof in - let metano,context,ty = CicUtil.lookup_meta goal metasenv in - (* We don't know if [term] is a subterm of [ty] or a subterm of *) - (* the type of one metavariable. So we replace it everywhere. *) - (*CSC: Il vero problema e' che non sapendo dove sia il term non *) - (*CSC: sappiamo neppure quale sia il suo contesto!!!! Insomma, *) - (*CSC: e' meglio prima cercare il termine e scoprirne il *) - (*CSC: contesto, poi ridurre e infine rimpiazzare. *) - let replace context where terms = - (*CSC: Per il momento se la riduzione fallisce significa solamente che *) - (*CSC: siamo nel contesto errato. Metto il try, ma che schifo!!!! *) - (*CSC: Anche perche' cosi' catturo anche quelle del replace che non dovrei *) - try - let terms, terms' = - List.split - (List.map - (fun i, t -> t, - (let x, _, _ = CicMetaSubst.delift_rels [] metasenv i t in - let t' = reduction context x in - CicSubstitution.lift i t')) - terms) - in - ProofEngineReduction.replace ~equality:(==) ~what:terms ~with_what:terms' - ~where:where - (* FIXME this is a catch ALL... bad thing *) - with exc -> (*prerr_endline (Printexc.to_string exc);*) where - in - let find_pattern_for name = - try Some (snd(List.find (fun (n, pat) -> Cic.Name n = name) hyp_patterns)) - with Not_found -> None - in - let ty' = - match goal_pattern with - | None -> replace context ty [0,ty] - | Some pat -> - let terms = CicUtil.select ~term:ty ~context:pat in - replace context ty terms - in - let context' = - if hyp_patterns <> [] then - List.fold_right - (fun entry context -> - match entry with - | Some (name,Cic.Decl term) -> - (match find_pattern_for name with - | None -> entry::context - | Some pat -> - let terms = CicUtil.select ~term ~context:pat in - let where = replace context term terms in - let entry = Some (name,Cic.Decl where) in - entry::context) - | Some (name,Cic.Def (term, None)) -> - (match find_pattern_for name with - | None -> entry::context - | Some pat -> - let terms = CicUtil.select ~term ~context:pat in - let where = replace context term terms in - let entry = Some (name,Cic.Def (where,None)) in - entry::context) - | _ -> entry::context - ) context [] + let (metano,context,ty) as conjecture = CicUtil.lookup_meta goal metasenv in + let change subst where terms = + if terms = [] then where else - context - in + let terms, terms' = + List.split (List.map (fun (context, t) -> t, reduction context t) terms) + in + let where' = + ProofEngineReduction.replace ~equality:(==) ~what:terms ~with_what:terms' + ~where:where + in + CicMetaSubst.apply_subst subst where' in + let (subst,metasenv,ugraph,selected_context,selected_ty) = + ProofEngineHelpers.select ~metasenv ~ugraph:CicUniv.empty_ugraph + ~conjecture ~pattern in + let ty' = change subst ty selected_ty in + let context' = + List.fold_right2 + (fun entry selected_entry context' -> + match entry,selected_entry with + None,None -> None::context' + | Some (name,Cic.Decl ty),Some (`Decl selected_ty) -> + let ty' = change subst ty selected_ty in + Some (name,Cic.Decl ty')::context' + | Some (name,Cic.Def (bo,ty)),Some (`Def (selected_bo,selected_ty)) -> + let bo' = change subst bo selected_bo in + let ty' = + match ty,selected_ty with + None,None -> None + | Some ty,Some selected_ty -> Some (change subst ty selected_ty) + | _,_ -> assert false + in + Some (name,Cic.Def (bo',ty'))::context' + | _,_ -> assert false + ) context selected_context [] in let metasenv' = List.map (function | (n,_,_) when n = metano -> (metano,context',ty') @@ -116,52 +73,124 @@ let reduction_tac ~reduction ~pattern:(hyp_patterns,goal_pattern) (proof,goal) = (curi,metasenv',pbo,pty), [metano] ;; -let simpl_tac ~pattern = +let simpl_tac ~pattern = mk_tactic (reduction_tac ~reduction:ProofEngineReduction.simpl ~pattern);; -let reduce_tac ~pattern = +let reduce_tac ~pattern = mk_tactic (reduction_tac ~reduction:ProofEngineReduction.reduce ~pattern);; + +let unfold_tac what ~pattern = + mk_tactic (reduction_tac ~reduction:(ProofEngineReduction.unfold ?what) + ~pattern);; -let whd_tac ~pattern = +let whd_tac ~pattern = mk_tactic (reduction_tac ~reduction:CicReduction.whd ~pattern);; -let normalize_tac ~pattern = - mk_tactic (reduction_tac ~reduction:CicReduction.normalize ~pattern );; +let normalize_tac ~pattern = + mk_tactic (reduction_tac ~reduction:CicReduction.normalize ~pattern);; -let fold_tac ~reduction ~also_in_hypotheses ~term = - let fold_tac ~reduction ~also_in_hypotheses ~term (proof,goal) = +exception NotConvertible + +(* Note: this code is almost identical to reduction_tac and +* it could be unified by making the change function a callback *) +(* CSC: with_what is parsed in the context of the goal, but it should replace + something that lives in a completely different context. Thus we + perform a delift + lift phase to move it in the right context. However, + in this way the tactic is less powerful than expected: with_what cannot + reference variables that are local to the term that is going to be + replaced. To fix this we should parse with_what in the context of the + term(s) to be replaced. *) +let change_tac ~pattern with_what = + let change_tac ~pattern ~with_what (proof, goal) = let curi,metasenv,pbo,pty = proof in - let metano,context,ty = CicUtil.lookup_meta goal metasenv in - let term' = reduction context term in - (* We don't know if [term] is a subterm of [ty] or a subterm of *) - (* the type of one metavariable. So we replace it everywhere. *) - (*CSC: ma si potrebbe ovviare al problema. Ma non credo *) - (*CSC: che si guadagni nulla in fatto di efficienza. *) - let replace = - ProofEngineReduction.replace ~equality:(=) ~what:[term'] ~with_what:[term] + let (metano,context,ty) as conjecture = CicUtil.lookup_meta goal metasenv in + let context_len = List.length context in + let change subst context'_len where terms = + if terms = [] then where + else + let terms, terms' = + List.split + (List.map + (fun (context_of_t, t) -> + let context_of_t_len = List.length context_of_t in + let with_what_in_context' = + if context_len > context'_len then + begin + let with_what,subst,metasenv' = + CicMetaSubst.delift_rels [] metasenv + (context_len - context'_len) with_what + in + assert (subst = []); + assert (metasenv = metasenv'); + with_what + end + else + with_what in + let with_what_in_context_of_t = + if context_of_t_len > context'_len then + CicSubstitution.lift (context_of_t_len - context'_len) + with_what_in_context' + else + with_what in + let _,u = + CicTypeChecker.type_of_aux' metasenv context_of_t with_what + CicUniv.empty_ugraph in + let b,_ = + CicReduction.are_convertible ~metasenv context_of_t t with_what u in + if b then + t, with_what_in_context_of_t + else + raise NotConvertible) terms) in - let ty' = replace ty in - let metasenv' = - let context' = - if also_in_hypotheses then - List.map - (function - Some (n,Cic.Decl t) -> Some (n,Cic.Decl (replace t)) - | Some (n,Cic.Def (t,None)) -> Some (n,Cic.Def ((replace t),None)) - | None -> None - | Some (_,Cic.Def (_,Some _)) -> assert false - ) context - else - context - in - List.map - (function - (n,_,_) when n = metano -> (metano,context',ty') - | _ as t -> t - ) metasenv - + let where' = + ProofEngineReduction.replace ~equality:(==) ~what:terms ~with_what:terms' + ~where:where in - (curi,metasenv',pbo,pty), [metano] + CicMetaSubst.apply_subst subst where' in + let (subst,metasenv,ugraph,selected_context,selected_ty) = + ProofEngineHelpers.select ~metasenv ~ugraph:CicUniv.empty_ugraph ~conjecture + ~pattern in + let ty' = change subst context_len ty selected_ty in + let context' = + List.fold_right2 + (fun entry selected_entry context' -> + let context'_len = List.length context' in + match entry,selected_entry with + None,None -> None::context' + | Some (name,Cic.Decl ty),Some (`Decl selected_ty) -> + let ty' = change subst context'_len ty selected_ty in + Some (name,Cic.Decl ty')::context' + | Some (name,Cic.Def (bo,ty)),Some (`Def (selected_bo,selected_ty)) -> + let bo' = change subst context'_len bo selected_bo in + let ty' = + match ty,selected_ty with + None,None -> None + | Some ty,Some selected_ty -> + Some (change subst context'_len ty selected_ty) + | _,_ -> assert false + in + Some (name,Cic.Def (bo',ty'))::context' + | _,_ -> assert false + ) context selected_context [] in + let metasenv' = + List.map (function + | (n,_,_) when n = metano -> (metano,context',ty') + | _ as t -> t + ) metasenv + in + (curi,metasenv',pbo,pty), [metano] + in + mk_tactic (change_tac ~pattern ~with_what) + +let fold_tac ~reduction ~term ~pattern = + let fold_tac ~reduction ~term ~pattern:(wanted,hyps_pat,concl_pat) status = + assert (wanted = None); (* this should be checked syntactically *) + let proof,goal = status in + let _,metasenv,_,_ = proof in + let _,context,_ = CicUtil.lookup_meta goal metasenv in + let reduced_term = reduction context term in + apply_tactic + (change_tac ~pattern:(Some reduced_term,hyps_pat,concl_pat) term) status in - mk_tactic (fold_tac ~reduction ~also_in_hypotheses ~term) + mk_tactic (fold_tac ~reduction ~term ~pattern) ;;