+ 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 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