-(* FG: subst tactic *********************************************************)
-
-(* FG: This should be replaced by T.try_tactic *)
-let try_tactic ~tactic =
- let try_tactic status =
- try PET.apply_tactic tactic status with
- | PET.Fail _ -> PET.apply_tactic T.id_tac status
- in
- PET.mk_tactic try_tactic
-
-let msg0 = lazy "Subst: not found in context"
-let msg1 = lazy "Subst: not a simple equality"
-let msg2 = lazy "Subst: recursive equation"
-
-let subst_tac ~hyp =
- let hole = C.Implicit (Some `Hole) in
- let subst_tac status =
- let (proof, goal) = status in
- let (_, metasenv, _, _) = proof in
- let _, context, _ = CicUtil.lookup_meta goal metasenv in
- let what = match PEH.get_rel context hyp with
- | Some t -> t
- | None -> raise (PET.Fail msg0)
- in
- let ty, _ = TC.type_of_aux' metasenv context what CicUniv.empty_ugraph in
- let direction, i, t = match ty with
- | (C.Appl [(C.MutInd (uri, 0, [])); _; C.Rel i; t])
- when LO.is_eq_URI uri -> `LeftToRight, i, t
- | (C.Appl [(C.MutInd (uri, 0, [])); _; t; C.Rel i])
- when LO.is_eq_URI uri -> `RightToLeft, i, t
- | _ -> raise (PET.Fail msg1)
- in
- let rewrite pattern =
- try_tactic ~tactic:(rewrite_tac ~direction ~pattern what)
- in
- let var = match PEH.get_name context i with
- | Some name -> name
- | None -> raise (PET.Fail msg0)
- in
- if DTI.does_not_occur i t then () else raise (PET.Fail msg2);
- let map self = function
- | Some (C.Name s, _) when s <> self ->
- Some (rewrite (None, [(s, hole)], None))
- | _ -> None
- in
- let rew_hips = PEH.list_rev_map_filter (map hyp) context in
- let rew_concl = rewrite (None, [], Some hole) in
- let clear = PESR.clear ~hyps:[hyp; var] in
- let tactics = List.rev_append (rew_concl :: rew_hips) [clear] in
- PET.apply_tactic (T.seq ~tactics) status
- in
- PET.mk_tactic subst_tac
-
-let subst_tac =
- let subst hyp = try_tactic ~tactic:(subst_tac hyp) in
- let map = function
- | Some (C.Name s, _) -> Some (subst s)
- | _ -> None
- in
- let subst_tac status =
- let (proof, goal) = status in
- let (_, metasenv, _, _) = proof in
- let _, context, _ = CicUtil.lookup_meta goal metasenv in
- let tactics = PEH.list_rev_map_filter map context in
- PET.apply_tactic (T.seq ~tactics) status
- in
- PET.mk_tactic subst_tac