* http://cs.unibo.it/helm/.
*)
-(*
-let reduction_tac ~reduction ~status:(proof,goal) =
- let curi,metasenv,pbo,pty = proof in
- let metano,context,ty = List.find (function (m,_,_) -> m=goal) metasenv in
- let new_ty = reduction context ty in
- let new_metasenv =
- List.map
- (function
- (n,_,_) when n = metano -> (metano,context,new_ty)
+open ProofEngineTypes
+
+(* 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) as conjecture = CicUtil.lookup_meta goal metasenv in
+ let change subst where terms metasenv ugraph =
+ if terms = [] then where, metasenv, ugraph
+ else
+ let pairs, metasenv, ugraph =
+ List.fold_left
+ (fun (pairs, metasenv, ugraph) (context, t) ->
+ let reduction, metasenv, ugraph = reduction context metasenv ugraph in
+ ((t, reduction context t) :: pairs), metasenv, ugraph)
+ ([], metasenv, ugraph)
+ terms
+ in
+ let terms, terms' = List.split pairs in
+ let where' =
+ ProofEngineReduction.replace ~equality:(==) ~what:terms ~with_what:terms'
+ ~where:where
+ in
+ CicMetaSubst.apply_subst subst where', metasenv, ugraph
+ in
+ let (subst,metasenv,ugraph,selected_context,selected_ty) =
+ ProofEngineHelpers.select ~metasenv ~ugraph:CicUniv.empty_ugraph
+ ~conjecture ~pattern
+ in
+ let ty', metasenv, ugraph = change subst ty selected_ty metasenv ugraph in
+ let context', metasenv, ugraph =
+ List.fold_right2
+ (fun entry selected_entry (context', metasenv, ugraph) ->
+ match entry,selected_entry with
+ None,None -> None::context', metasenv, ugraph
+ | Some (name,Cic.Decl ty),Some (`Decl selected_ty) ->
+ let ty', metasenv, ugraph =
+ change subst ty selected_ty metasenv ugraph
+ in
+ Some (name,Cic.Decl ty')::context', metasenv, ugraph
+ | Some (name,Cic.Def (bo,ty)),Some (`Def (selected_bo,selected_ty)) ->
+ let bo', metasenv, ugraph =
+ change subst bo selected_bo metasenv ugraph
+ in
+ let ty', metasenv, ugraph =
+ match ty,selected_ty with
+ None,None -> None, metasenv, ugraph
+ | Some ty,Some selected_ty ->
+ let ty', metasenv, ugraph =
+ change subst ty selected_ty metasenv ugraph
+ in
+ Some ty', metasenv, ugraph
+ | _,_ -> assert false
+ in
+ (Some (name,Cic.Def (bo',ty'))::context'), metasenv, ugraph
+ | _,_ -> assert false
+ ) context selected_context ([], metasenv, ugraph) in
+ let metasenv' =
+ List.map (function
+ | (n,_,_) when n = metano -> (metano,context',ty')
| _ as t -> t
) metasenv
- in
- (curi,new_metasenv,pbo,pty), [metano]
+ in
+ (curi,metasenv',pbo,pty), [metano]
;;
-*)
-(* The default of term is the thesis of the goal to be prooved *)
-let reduction_tac ~also_in_hypotheses ~reduction ~terms ~status:(proof,goal) =
- let curi,metasenv,pbo,pty = proof in
- let metano,context,ty = List.find (function (m,_,_) -> m=goal) metasenv in
- let terms =
- match terms with None -> [ty] | Some l -> l
+let simpl_tac ~pattern =
+ mk_tactic (reduction_tac
+ ~reduction:(const_lazy_reduction ProofEngineReduction.simpl) ~pattern)
+
+let reduce_tac ~pattern =
+ mk_tactic (reduction_tac
+ ~reduction:(const_lazy_reduction ProofEngineReduction.reduce) ~pattern)
+
+let unfold_tac what ~pattern =
+ let reduction =
+ match what with
+ | None -> const_lazy_reduction (ProofEngineReduction.unfold ?what:None)
+ | Some lazy_term ->
+ (fun context metasenv ugraph ->
+ let what, metasenv, ugraph = lazy_term context metasenv ugraph in
+ ProofEngineReduction.unfold ~what, metasenv, ugraph)
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=
-(*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' = List.map (reduction context) terms in
- ProofEngineReduction.replace ~equality:(==) ~what:terms ~with_what:terms'
- ~where:where
- with
- _ -> where
- in
- let ty' = replace context ty in
- let context' =
- if also_in_hypotheses then
- List.fold_right
- (fun entry context ->
- match entry with
- Some (name,Cic.Def t) ->
- (Some (name,Cic.Def (replace context t)))::context
- | Some (name,Cic.Decl t) ->
- (Some (name,Cic.Decl (replace context t)))::context
- | None -> None::context
- ) context []
- else
- context
+ mk_tactic (reduction_tac ~reduction ~pattern)
+
+let whd_tac ~pattern =
+ mk_tactic (reduction_tac
+ ~reduction:(const_lazy_reduction CicReduction.whd) ~pattern)
+
+let normalize_tac ~pattern =
+ mk_tactic (reduction_tac
+ ~reduction:(const_lazy_reduction CicReduction.normalize) ~pattern)
+
+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) as conjecture = CicUtil.lookup_meta goal metasenv in
+ let change subst where terms metasenv ugraph =
+ if terms = [] then where, metasenv, ugraph
+ else
+ let pairs, metasenv, ugraph =
+ List.fold_left
+ (fun (pairs, metasenv, ugraph) (context_of_t, t) ->
+ let with_what, metasenv, ugraph =
+ with_what context_of_t metasenv ugraph
+ in
+ let _,u =
+ CicTypeChecker.type_of_aux' metasenv context_of_t with_what ugraph
+ in
+ let b,_ =
+ CicReduction.are_convertible ~metasenv context_of_t t with_what u
+ in
+ if b then
+ ((t, with_what) :: pairs), metasenv, ugraph
+ else
+ raise NotConvertible)
+ ([], metasenv, ugraph)
+ terms
in
- let metasenv' =
- List.map
- (function
- (n,_,_) when n = metano -> (metano,context',ty')
- | _ as t -> t
- ) metasenv
+ let terms, terms' = List.split pairs in
+ let where' =
+ ProofEngineReduction.replace ~equality:(==) ~what:terms ~with_what:terms'
+ ~where:where
in
- (curi,metasenv',pbo,pty), [metano]
-;;
+ CicMetaSubst.apply_subst subst where', metasenv, ugraph
+ in
+ let (subst,metasenv,ugraph,selected_context,selected_ty) =
+ ProofEngineHelpers.select ~metasenv ~ugraph:CicUniv.empty_ugraph ~conjecture
+ ~pattern in
+ let ty', metasenv, ugraph = change subst ty selected_ty metasenv ugraph in
+ let context', metasenv, ugraph =
+ List.fold_right2
+ (fun entry selected_entry (context', metasenv, ugraph) ->
+ match entry,selected_entry with
+ None,None -> (None::context'), metasenv, ugraph
+ | Some (name,Cic.Decl ty),Some (`Decl selected_ty) ->
+ let ty', metasenv, ugraph =
+ change subst ty selected_ty metasenv ugraph
+ in
+ (Some (name,Cic.Decl ty')::context'), metasenv, ugraph
+ | Some (name,Cic.Def (bo,ty)),Some (`Def (selected_bo,selected_ty)) ->
+ let bo', metasenv, ugraph =
+ change subst bo selected_bo metasenv ugraph
+ in
+ let ty', metasenv, ugraph =
+ match ty,selected_ty with
+ None,None -> None, metasenv, ugraph
+ | Some ty,Some selected_ty ->
+ let ty', metasenv, ugraph =
+ change subst ty selected_ty metasenv ugraph
+ in
+ Some ty', metasenv, ugraph
+ | _,_ -> assert false
+ in
+ (Some (name,Cic.Def (bo',ty'))::context'), metasenv, ugraph
+ | _,_ -> assert false
+ ) context selected_context ([], metasenv, ugraph) 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 simpl_tac = reduction_tac ~reduction:ProofEngineReduction.simpl ;;
-let reduce_tac = reduction_tac ~reduction:ProofEngineReduction.reduce ;;
-let whd_tac = reduction_tac ~reduction:CicReduction.whd ;;
+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 reduced_term =
+ (fun context metasenv ugraph ->
+ let term, metasenv, ugraph = term context metasenv ugraph in
+ let reduction, metasenv, ugraph = reduction context metasenv ugraph in
+ reduction context term, metasenv, ugraph)
+ in
+ apply_tactic
+ (change_tac ~pattern:(Some reduced_term,hyps_pat,concl_pat) term) status
+ in
+ mk_tactic (fold_tac ~reduction ~term ~pattern)
-let fold_tac ~reduction ~also_in_hypotheses ~term ~status:(proof,goal) =
- let curi,metasenv,pbo,pty = proof in
- let metano,context,ty = List.find (function (m,_,_) -> m=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]
- 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) -> Some (n,Cic.Def (replace t))
- | None -> None
- ) context
- else
- context
- in
- List.map
- (function
- (n,_,_) when n = metano -> (metano,context',ty')
- | _ as t -> t
- ) metasenv
-
- in
- (curi,metasenv',pbo,pty), [metano]
-;;