-(* type naif_indexing =
- (Cic.term * ((bool * Inference.equality) list)) list
-;; *)
-
-type pos = Left | Right
-;;
-
-let head_of_term =
- function
- | Cic.Appl hd::tl -> hd
- | t -> t
-;;
-
-let index table eq =
- let (_,(_,l,r,ordering),_,_) = eq in
- let hl = head_of_term l in
- let hr = head_of_term r in
- let index x pos =
- let x_entry =
- try Hashtbl.find table x
- with Not_found -> [] in
- Hashtbl.replace table x (pos,eq)::x_entry in
- (match ordering with
- | Utils.Gt ->
- index hl Left
- | Utils.Lt ->
- index hr Right
- | _ -> index hl Left;
- index hr Right);
- table
-;;
-
-let demodulate_term env table cmp term =
- let hd_term = head_of_term term in
- let candidates = Hashtbl.find table hd_term in
-
-
-
-
+
+type retrieval_mode = Matching | Unification;;
+
+
+let empty_table () =
+ Path_indexing.PSTrie.empty
+;;
+
+let index = Path_indexing.index
+and remove_index = Path_indexing.remove_index
+and in_index = Path_indexing.in_index;;
+let get_candidates mode trie term =
+ let s =
+ match mode with
+ | Matching -> Path_indexing.retrieve_generalizations trie term
+ | Unification -> Path_indexing.retrieve_unifiables trie term
+ in
+ Path_indexing.PosEqSet.elements s
+;;
+
+
+(*
+let empty_table () =
+ Discrimination_tree.DiscriminationTree.empty
+;;
+
+let index = Discrimination_tree.index
+and remove_index = Discrimination_tree.remove_index
+and in_index = Discrimination_tree.in_index;;
+
+let get_candidates mode tree term =
+ match mode with
+ | Matching -> Discrimination_tree.retrieve_generalizations tree term
+ | Unification -> Discrimination_tree.retrieve_unifiables tree term
+;;
+*)
+
+
+let rec find_matches metasenv context ugraph lift_amount term =
+ let module C = Cic in
+ let module U = Utils in
+ let module S = CicSubstitution in
+ let module M = CicMetaSubst in
+ let module HL = HelmLibraryObjects in
+ let cmp = !Utils.compare_terms in
+ let names = Utils.names_of_context context in
+ function
+ | [] -> None
+ | candidate::tl ->
+ let pos, (proof, (ty, left, right, o), metas, args) = candidate in
+ let do_match c other eq_URI =
+ let subst', metasenv', ugraph' =
+ Inference.matching (metasenv @ metas) context
+ term (S.lift lift_amount c) ugraph
+ in
+ Some (C.Rel (1 + lift_amount), subst', metasenv', ugraph',
+ (candidate, eq_URI))
+ in
+ let c, other, eq_URI =
+ if pos = Utils.Left then left, right, HL.Logic.eq_ind_URI
+ else right, left, HL.Logic.eq_ind_r_URI
+ in
+ if o <> U.Incomparable then
+ try
+ do_match c other eq_URI
+ with e ->
+ find_matches metasenv context ugraph lift_amount term tl
+ else
+ let res = try do_match c other eq_URI with e -> None in
+ match res with
+ | Some (_, s, _, _, _) ->
+ let c' = M.apply_subst s c
+ and other' = M.apply_subst s other in
+ let order = cmp c' other' in
+ let names = U.names_of_context context in
+ if order = U.Gt then
+ res
+ else
+ find_matches metasenv context ugraph lift_amount term tl
+ | None ->
+ find_matches metasenv context ugraph lift_amount term tl
+;;
+
+
+let rec find_all_matches ?(unif_fun=CicUnification.fo_unif)
+ metasenv context ugraph lift_amount term =
+ let module C = Cic in
+ let module U = Utils in
+ let module S = CicSubstitution in
+ let module M = CicMetaSubst in
+ let module HL = HelmLibraryObjects in
+ let cmp = !Utils.compare_terms in
+ let names = Utils.names_of_context context in
+ function
+ | [] -> []
+ | candidate::tl ->
+ let pos, (proof, (ty, left, right, o), metas, args) = candidate in
+ let do_match c other eq_URI =
+ let subst', metasenv', ugraph' =
+ unif_fun (metasenv @ metas) context
+ term (S.lift lift_amount c) ugraph
+ in
+ (C.Rel (1 + lift_amount), subst', metasenv', ugraph',
+ (candidate, eq_URI))
+ in
+ let c, other, eq_URI =
+ if pos = Utils.Left then left, right, HL.Logic.eq_ind_URI
+ else right, left, HL.Logic.eq_ind_r_URI
+ in
+ if o <> U.Incomparable then
+ try
+ let res = do_match c other eq_URI in
+ res::(find_all_matches ~unif_fun metasenv context ugraph
+ lift_amount term tl)
+ with e ->
+ find_all_matches ~unif_fun metasenv context ugraph
+ lift_amount term tl
+ else
+ try
+ let res = do_match c other eq_URI in
+ match res with
+ | _, s, _, _, _ ->
+ let c' = M.apply_subst s c
+ and other' = M.apply_subst s other in
+ let order = cmp c' other' in
+ let names = U.names_of_context context in
+ if order <> U.Lt && order <> U.Le then
+ res::(find_all_matches ~unif_fun metasenv context ugraph
+ lift_amount term tl)
+ else
+ find_all_matches ~unif_fun metasenv context ugraph
+ lift_amount term tl
+ with e ->
+ find_all_matches ~unif_fun metasenv context ugraph
+ lift_amount term tl
+;;
+
+
+let subsumption env table target =
+ let _, (ty, tl, tr, _), tmetas, _ = target in
+ let metasenv, context, ugraph = env in
+ let metasenv = metasenv @ tmetas in
+ let samesubst subst subst' =
+ let tbl = Hashtbl.create (List.length subst) in
+ List.iter (fun (m, (c, t1, t2)) -> Hashtbl.add tbl m (c, t1, t2)) subst;
+ List.for_all
+ (fun (m, (c, t1, t2)) ->
+ try
+ let c', t1', t2' = Hashtbl.find tbl m in
+ if (c = c') && (t1 = t1') && (t2 = t2') then true
+ else false
+ with Not_found ->
+ true)
+ subst'
+ in
+ let subsaux left right =
+ let leftc = get_candidates Matching table left in
+ let leftr =
+ find_all_matches ~unif_fun:Inference.matching
+ metasenv context ugraph 0 left leftc
+ in
+ let ok what (_, subst, menv, ug, ((pos, (_, (_, l, r, o), _, _)), _)) =
+ try
+ let other = if pos = Utils.Left then r else l in
+ let subst', menv', ug' =
+ Inference.matching metasenv context what other ugraph in
+ samesubst subst subst'
+ with e ->
+ false
+ in
+ let r = List.exists (ok right) leftr in
+ if r then
+ true
+ else
+ let rightc = get_candidates Matching table right in
+ let rightr =
+ find_all_matches ~unif_fun:Inference.matching
+ metasenv context ugraph 0 right rightc
+ in
+ List.exists (ok left) rightr
+ in
+ let res = subsaux tl tr in
+ if res then (
+ Printf.printf "subsumption!:\ntarget: %s\n"
+ (Inference.string_of_equality ~env target);
+ print_newline ();
+ );
+ res
+;;
+
+
+let rec demodulate_term metasenv context ugraph table lift_amount term =
+ let module C = Cic in
+ let module S = CicSubstitution in
+ let module M = CicMetaSubst in
+ let module HL = HelmLibraryObjects in
+ let candidates = get_candidates Matching table term in
+ match term with
+ | C.Meta _ -> None
+ | term ->
+ let res =
+ find_matches metasenv context ugraph lift_amount term candidates
+ in
+ if res <> None then
+ res
+ else
+ match term with
+ | C.Appl l ->
+ let res, ll =
+ List.fold_left
+ (fun (res, tl) t ->
+ if res <> None then
+ (res, tl @ [S.lift 1 t])
+ else
+ let r =
+ demodulate_term metasenv context ugraph table
+ lift_amount t
+ in
+ match r with
+ | None -> (None, tl @ [S.lift 1 t])
+ | Some (rel, _, _, _, _) -> (r, tl @ [rel]))
+ (None, []) l
+ in (
+ match res with
+ | None -> None
+ | Some (_, subst, menv, ug, eq_found) ->
+ Some (C.Appl ll, subst, menv, ug, eq_found)
+ )
+ | C.Prod (nn, s, t) ->
+ let r1 =
+ demodulate_term metasenv context ugraph table lift_amount s in (
+ match r1 with
+ | None ->
+ let r2 =
+ demodulate_term metasenv
+ ((Some (nn, C.Decl s))::context) ugraph
+ table (lift_amount+1) t
+ in (
+ match r2 with
+ | None -> None
+ | Some (t', subst, menv, ug, eq_found) ->
+ Some (C.Prod (nn, (S.lift 1 s), t'),
+ subst, menv, ug, eq_found)
+ )
+ | Some (s', subst, menv, ug, eq_found) ->
+ Some (C.Prod (nn, s', (S.lift 1 t)),
+ subst, menv, ug, eq_found)
+ )
+ | t ->
+ None
+;;
+
+
+let rec demodulation newmeta env table target =
+ let module C = Cic in
+ let module S = CicSubstitution in
+ let module M = CicMetaSubst in
+ let module HL = HelmLibraryObjects in
+ let metasenv, context, ugraph = env in
+ let proof, (eq_ty, left, right, order), metas, args = target in
+ let metasenv' = metasenv @ metas in
+ let build_newtarget is_left (t, subst, menv, ug, (eq_found, eq_URI)) =
+ let pos, (proof', (ty, what, other, _), menv', args') = eq_found in
+ let what, other = if pos = Utils.Left then what, other else other, what in
+ let newterm, newproof =
+ let bo = M.apply_subst subst (S.subst other t) in
+ let bo'' =
+ C.Appl ([C.MutInd (HL.Logic.eq_URI, 0, []);
+ S.lift 1 eq_ty] @
+ if is_left then [bo; S.lift 1 right] else [S.lift 1 left; bo])
+ in
+ let t' = C.Lambda (C.Anonymous, ty, bo'') in
+ bo,
+ M.apply_subst subst (C.Appl [C.Const (eq_URI, []); ty; what; t';
+ proof; other; proof'])
+ in
+ let left, right = if is_left then newterm, right else left, newterm in
+ let m =
+ (Inference.metas_of_term left) @ (Inference.metas_of_term right)
+ in
+ let newmetasenv = List.filter (fun (i, _, _) -> List.mem i m) metas
+ and newargs =
+ List.filter
+ (function C.Meta (i, _) -> List.mem i m | _ -> assert false)
+ args
+ in
+ let ordering = !Utils.compare_terms left right in
+ newmeta, (newproof, (eq_ty, left, right, ordering), newmetasenv, newargs)
+ in
+ let res = demodulate_term metasenv' context ugraph table 0 left in
+ let build_identity (p, (t, l, r, o), m, a) =
+ match o with
+ | Utils.Gt -> (p, (t, r, r, Utils.Eq), m, a)
+ | _ -> (p, (t, l, l, Utils.Eq), m, a)
+ in
+ match res with
+ | Some t ->
+ let newmeta, newtarget = build_newtarget true t in
+ if (Inference.is_identity (metasenv', context, ugraph) newtarget) ||
+ (Inference.meta_convertibility_eq target newtarget) then
+ newmeta, newtarget
+ else
+ if subsumption env table newtarget then
+ newmeta, build_identity newtarget
+ else
+ demodulation newmeta env table newtarget
+ | None ->
+ let res = demodulate_term metasenv' context ugraph table 0 right in
+ match res with
+ | Some t ->
+ let newmeta, newtarget = build_newtarget false t in
+ if (Inference.is_identity (metasenv', context, ugraph) newtarget) ||
+ (Inference.meta_convertibility_eq target newtarget) then
+ newmeta, newtarget
+ else
+ if subsumption env table newtarget then
+ newmeta, build_identity newtarget
+ else
+ demodulation newmeta env table newtarget
+ | None ->
+ newmeta, target
+;;
+
+
+let rec betaexpand_term metasenv context ugraph table lift_amount term =
+ let module C = Cic in
+ let module S = CicSubstitution in
+ let module M = CicMetaSubst in
+ let module HL = HelmLibraryObjects in
+ let candidates = get_candidates Unification table term in
+ let res, lifted_term =
+ match term with
+ | C.Meta (i, l) ->
+ let l', lifted_l =
+ List.fold_right
+ (fun arg (res, lifted_tl) ->
+ match arg with
+ | Some arg ->
+ let arg_res, lifted_arg =
+ betaexpand_term metasenv context ugraph table
+ lift_amount arg in
+ let l1 =
+ List.map
+ (fun (t, s, m, ug, eq_found) ->
+ (Some t)::lifted_tl, s, m, ug, eq_found)
+ arg_res
+ in
+ (l1 @
+ (List.map
+ (fun (l, s, m, ug, eq_found) ->
+ (Some lifted_arg)::l, s, m, ug, eq_found)
+ res),
+ (Some lifted_arg)::lifted_tl)
+ | None ->
+ (List.map
+ (fun (r, s, m, ug, eq_found) ->
+ None::r, s, m, ug, eq_found) res,
+ None::lifted_tl)
+ ) l ([], [])
+ in
+ let e =
+ List.map
+ (fun (l, s, m, ug, eq_found) ->
+ (C.Meta (i, l), s, m, ug, eq_found)) l'
+ in
+ e, C.Meta (i, lifted_l)
+
+ | C.Rel m ->
+ [], if m <= lift_amount then C.Rel m else C.Rel (m+1)
+
+ | C.Prod (nn, s, t) ->
+ let l1, lifted_s =
+ betaexpand_term metasenv context ugraph table lift_amount s in
+ let l2, lifted_t =
+ betaexpand_term metasenv ((Some (nn, C.Decl s))::context) ugraph
+ table (lift_amount+1) t in
+ let l1' =
+ List.map
+ (fun (t, s, m, ug, eq_found) ->
+ C.Prod (nn, t, lifted_t), s, m, ug, eq_found) l1
+ and l2' =
+ List.map
+ (fun (t, s, m, ug, eq_found) ->
+ C.Prod (nn, lifted_s, t), s, m, ug, eq_found) l2 in
+ l1' @ l2', C.Prod (nn, lifted_s, lifted_t)
+
+ | C.Appl l ->
+ let l', lifted_l =
+ List.fold_right
+ (fun arg (res, lifted_tl) ->
+ let arg_res, lifted_arg =
+ betaexpand_term metasenv context ugraph table lift_amount arg
+ in
+ let l1 =
+ List.map
+ (fun (a, s, m, ug, eq_found) ->
+ a::lifted_tl, s, m, ug, eq_found)
+ arg_res
+ in
+ (l1 @
+ (List.map
+ (fun (r, s, m, ug, eq_found) ->
+ lifted_arg::r, s, m, ug, eq_found)
+ res),
+ lifted_arg::lifted_tl)
+ ) l ([], [])
+ in
+ (List.map
+ (fun (l, s, m, ug, eq_found) -> (C.Appl l, s, m, ug, eq_found)) l',
+ C.Appl lifted_l)
+
+ | t -> [], (S.lift lift_amount t)
+ in
+ match term with
+ | C.Meta _ -> res, lifted_term
+ | term ->
+ let r =
+ find_all_matches metasenv context ugraph lift_amount term candidates
+ in
+ r @ res, lifted_term
+;;
+
+
+let superposition_left (metasenv, context, ugraph) table target =
+ let module C = Cic in
+ let module S = CicSubstitution in
+ let module M = CicMetaSubst in
+ let module HL = HelmLibraryObjects in
+ let module CR = CicReduction in
+ let module U = Utils in
+ let proof, (eq_ty, left, right, ordering), _, _ = target in
+ let expansions, _ =
+ let term = if ordering = U.Gt then left else right in
+ betaexpand_term metasenv context ugraph table 0 term
+ in
+ let build_new (bo, s, m, ug, (eq_found, eq_URI)) =
+ let pos, (proof', (ty, what, other, _), menv', args') = eq_found in
+ let what, other = if pos = Utils.Left then what, other else other, what in
+ let newgoal, newproof =
+ let bo' = M.apply_subst s (S.subst other bo) in
+ let bo'' =
+ C.Appl (
+ [C.MutInd (HL.Logic.eq_URI, 0, []);
+ S.lift 1 eq_ty] @
+ if ordering = U.Gt then [bo'; S.lift 1 right]
+ else [S.lift 1 left; bo'])
+ in
+ let t' = C.Lambda (C.Anonymous, ty, bo'') in
+ bo',
+ M.apply_subst s
+ (C.Appl [C.Const (eq_URI, []); ty; what; t';
+ proof; other; proof'])
+ in
+ let left, right =
+ if ordering = U.Gt then newgoal, right else left, newgoal in
+ let neworder = !Utils.compare_terms left right in
+ (newproof, (eq_ty, left, right, neworder), [], [])
+ in
+ List.map build_new expansions
+;;
+
+
+let superposition_right newmeta (metasenv, context, ugraph) table target =
+ let module C = Cic in
+ let module S = CicSubstitution in
+ let module M = CicMetaSubst in
+ let module HL = HelmLibraryObjects in
+ let module CR = CicReduction in
+ let module U = Utils in
+ let eqproof, (eq_ty, left, right, ordering), newmetas, args = target in
+ let metasenv' = metasenv @ newmetas in
+ let maxmeta = ref newmeta in
+ let res1, res2 =
+ match ordering with
+ | U.Gt -> fst (betaexpand_term metasenv' context ugraph table 0 left), []
+ | U.Lt -> [], fst (betaexpand_term metasenv' context ugraph table 0 right)
+ | _ ->
+ let res l r =
+ List.filter
+ (fun (_, subst, _, _, _) ->
+ let subst = M.apply_subst subst in
+ let o = !Utils.compare_terms (subst l) (subst r) in
+ o <> U.Lt && o <> U.Le)
+ (fst (betaexpand_term metasenv' context ugraph table 0 l))
+ in
+ (res left right), (res right left)
+ in
+ let build_new ordering (bo, s, m, ug, (eq_found, eq_URI)) =
+ let pos, (proof', (ty, what, other, _), menv', args') = eq_found in
+ let what, other = if pos = Utils.Left then what, other else other, what in
+ let newgoal, newproof =
+ let bo' = M.apply_subst s (S.subst other bo) in
+ let bo'' =
+ C.Appl (
+ [C.MutInd (HL.Logic.eq_URI, 0, []); S.lift 1 eq_ty] @
+ if ordering = U.Gt then [bo'; S.lift 1 right]
+ else [S.lift 1 left; bo'])
+ in
+ let t' = C.Lambda (C.Anonymous, ty, bo'') in
+ bo',
+ M.apply_subst s
+ (C.Appl [C.Const (eq_URI, []); ty; what; t';
+ eqproof; other; proof'])
+ in
+ let newmeta, newequality =
+ let left, right =
+ if ordering = U.Gt then newgoal, M.apply_subst s right
+ else M.apply_subst s left, newgoal in
+ let neworder = !Utils.compare_terms left right
+ and newmenv = newmetas @ menv'
+ and newargs = args @ args' in
+ let eq' = (newproof, (eq_ty, left, right, neworder), newmenv, newargs)
+ and env = (metasenv, context, ugraph) in
+ let newm, eq' = Inference.fix_metas !maxmeta eq' in
+ newm, eq'
+ in
+ maxmeta := newmeta;
+ newequality
+ in
+ let new1 = List.map (build_new U.Gt) res1
+ and new2 = List.map (build_new U.Lt) res2 in
+ let ok = function
+ | _, (_, left, right, _), _, _ ->
+ not (fst (CR.are_convertible context left right ugraph))
+ in
+ (!maxmeta,
+ (List.filter ok (new1 @ new2)))
+;;