* http://cs.unibo.it/helm/.
*)
-let rewrite_tac ~direction ~pattern equality =
- let rewrite_tac ~direction ~pattern:(wanted,hyps_pat,concl_pat) equality status
+let rec rewrite_tac ~direction ~pattern equality =
+ let _rewrite_tac ~direction ~pattern:(wanted,hyps_pat,concl_pat) equality status
=
let module C = Cic in
let module U = UriManager in
let module PEH = ProofEngineHelpers in
let module PT = PrimitiveTactics in
assert (wanted = None); (* this should be checked syntactically *)
- assert (hyps_pat = []); (*CSC: not implemented yet! *)
let proof,goal = status in
- let if_right_to_left a b =
- match direction with
- | `RightToLeft -> a
- | `LeftToRight -> b
- in
let curi, metasenv, pbo, pty = proof in
let (metano,context,gty) as conjecture = CicUtil.lookup_meta goal metasenv in
+ match hyps_pat with
+ he::(_::_ as tl) ->
+ PET.apply_tactic
+ (Tacticals.then_
+ (rewrite_tac ~direction
+ ~pattern:(None,[he],Cic.Implicit None) equality)
+ (rewrite_tac ~direction ~pattern:(None,tl,concl_pat) equality)
+ ) status
+ | [_] as hyps_pat when concl_pat <> Cic.Implicit None ->
+ PET.apply_tactic
+ (Tacticals.then_
+ (rewrite_tac ~direction
+ ~pattern:(None,hyps_pat,Cic.Implicit None) equality)
+ (rewrite_tac ~direction ~pattern:(None,[],concl_pat) equality)
+ ) status
+ | _ ->
+ let arg,dir2,tac,concl_pat,gty =
+ match hyps_pat with
+ [] -> None,true,(fun ~term _ -> PT.exact_tac term),concl_pat,gty
+ | [name,pat] ->
+ let rec find_hyp n =
+ function
+ [] -> assert false
+ | Some (Cic.Name s,Cic.Decl ty)::_ when name = s ->
+ Cic.Rel n, CicSubstitution.lift n ty
+ | Some (Cic.Name s,Cic.Def _)::_ -> assert false (*CSC: not implemented yet! But does this make any sense?*)
+ | _::tl -> find_hyp (n+1) tl
+ in
+ let arg,gty = find_hyp 1 context in
+ let last_hyp_name_of_status (proof,goal) =
+ let curi, metasenv, pbo, pty = proof in
+ let metano,context,gty = CicUtil.lookup_meta goal metasenv in
+ match context with
+ (Some (Cic.Name s,_))::_ -> s
+ | _ -> assert false
+ in
+ let dummy = "dummy" in
+ Some arg,false,
+ (fun ~term typ ->
+ Tacticals.seq
+ ~tactics:
+ [ProofEngineStructuralRules.rename name dummy;
+ PT.letin_tac
+ ~mk_fresh_name_callback:(fun _ _ _ ~typ -> Cic.Name name) term;
+ ProofEngineStructuralRules.clearbody name;
+ ReductionTactics.change_tac
+ ~pattern:
+ (None,[name,Cic.Implicit (Some `Hole)],Cic.Implicit None)
+ (ProofEngineTypes.const_lazy_term typ);
+ ProofEngineStructuralRules.clear dummy
+ ]),
+ pat,gty
+ | _::_ -> assert false
+ in
+ let if_right_to_left do_not_change a b =
+ match direction with
+ | `RightToLeft -> if do_not_change then a else b
+ | `LeftToRight -> if do_not_change then b else a
+ in
let ty_eq,ugraph =
CicTypeChecker.type_of_aux' metasenv context equality
CicUniv.empty_ugraph in
equality
else
C.Appl (equality :: arguments) in
- let eq_ind, ty, t1, t2 =
+ (* t1x is t2 if we are rewriting in an hypothesis *)
+ let eq_ind, ty, t1, t2, t1x =
match ty_eq with
| C.Appl [C.MutInd (uri, 0, []); ty; t1; t2]
when LibraryObjects.is_eq_URI uri ->
let ind_uri =
- if_right_to_left LibraryObjects.eq_ind_URI LibraryObjects.eq_ind_r_URI
+ if_right_to_left dir2
+ LibraryObjects.eq_ind_URI LibraryObjects.eq_ind_r_URI
in
let eq_ind = C.Const (ind_uri uri,[]) in
- if_right_to_left (eq_ind, ty, t2, t1) (eq_ind, ty, t1, t2)
+ if dir2 then
+ if_right_to_left true (eq_ind,ty,t2,t1,t2) (eq_ind,ty,t1,t2,t1)
+ else
+ if_right_to_left true (eq_ind,ty,t1,t2,t2) (eq_ind,ty,t2,t1,t1)
| _ -> raise (PET.Fail (lazy "Rewrite: argument is not a proof of an equality")) in
(* now we always do as if direction was `LeftToRight *)
let fresh_name =
FreshNamesGenerator.mk_fresh_name
~subst:[] metasenv' context C.Anonymous ~typ:ty in
- let lifted_t1 = CicSubstitution.lift 1 t1 in
+ let lifted_t1 = CicSubstitution.lift 1 t1x in
let lifted_gty = CicSubstitution.lift 1 gty in
let lifted_conjecture =
metano,(Some (fresh_name,Cic.Decl ty))::context,lifted_gty in
let metasenv' = CicMetaSubst.apply_subst_metasenv subst metasenv' in
let what,with_what =
(* Note: Rel 1 does not live in the context context_of_t *)
- (* The replace_lifting_csc_0 function will take care of lifting it *)
+ (* The replace_lifting_csc 0 function will take care of lifting it *)
(* to context_of_t *)
List.fold_right
(fun (context_of_t,t) (l1,l2) -> t::l1, Cic.Rel 1::l2)
selected_terms_with_context ([],[]) in
+ let t1 = CicMetaSubst.apply_subst subst t1 in
+ let t2 = CicMetaSubst.apply_subst subst t2 in
+ let equality = CicMetaSubst.apply_subst subst equality in
let abstr_gty =
ProofEngineReduction.replace_lifting_csc 0
~equality:(==) ~what ~with_what:with_what ~where:lifted_gty in
let abstr_gty = CicMetaSubst.apply_subst subst abstr_gty in
- let t1 = CicMetaSubst.apply_subst subst t1 in
- let t2 = CicMetaSubst.apply_subst subst t2 in
- let equality = CicMetaSubst.apply_subst subst equality in
- let gty' = CicSubstitution.subst t2 abstr_gty in
- let irl = CicMkImplicit.identity_relocation_list_for_metavariable context in
- let metasenv' = (fresh_meta,context,gty')::metasenv' in
let pred = C.Lambda (fresh_name, ty, abstr_gty) in
+ (* The argument is either a meta if we are rewriting in the conclusion
+ or the hypothesis if we are rewriting in an hypothesis *)
+ let metasenv',arg,newtyp =
+ match arg with
+ None ->
+ let gty' = CicSubstitution.subst t2 abstr_gty in
+ let irl =
+ CicMkImplicit.identity_relocation_list_for_metavariable context in
+ let metasenv' = (fresh_meta,context,gty')::metasenv' in
+ metasenv', C.Meta (fresh_meta,irl), Cic.Rel (-1) (* dummy term, never used *)
+ | Some arg ->
+ let gty' = CicSubstitution.subst t1 abstr_gty in
+ metasenv,arg,gty'
+ in
let exact_proof =
- C.Appl [eq_ind ; ty ; t2 ; pred ; C.Meta (fresh_meta,irl) ; t1 ;equality]
+ C.Appl [eq_ind ; ty ; t2 ; pred ; arg ; t1 ;equality]
in
let (proof',goals) =
PET.apply_tactic
- (PT.exact_tac ~term:exact_proof) ((curi,metasenv',pbo,pty),goal)
+ (tac ~term:exact_proof newtyp) ((curi,metasenv',pbo,pty),goal)
in
- assert (List.length goals = 0) ;
let goals =
- ProofEngineHelpers.compare_metasenvs ~oldmetasenv:metasenv
- ~newmetasenv:metasenv'
+ goals@(ProofEngineHelpers.compare_metasenvs ~oldmetasenv:metasenv
+ ~newmetasenv:metasenv')
in
(proof',goals)
in
- ProofEngineTypes.mk_tactic (rewrite_tac ~direction ~pattern equality)
+ ProofEngineTypes.mk_tactic (_rewrite_tac ~direction ~pattern equality)
let rewrite_simpl_tac ~direction ~pattern equality =
projects / helm.git / blobdiff