X-Git-Url: http://matita.cs.unibo.it/gitweb/?a=blobdiff_plain;f=helm%2Focaml%2Fparamodulation%2Findexing.ml;h=84559b22247fdde62f74f2485562eb34fef34cbb;hb=a89f7271e79dc7dc81dc868a75125669c8decc16;hp=5c08d906d07bb5b6f94b9d5793dc7533ac347e87;hpb=50b01988edd12788a59aea3fb0f6704d5fd2bb69;p=helm.git

diff --git a/helm/ocaml/paramodulation/indexing.ml b/helm/ocaml/paramodulation/indexing.ml
index 5c08d906d..84559b222 100644
--- a/helm/ocaml/paramodulation/indexing.ml
+++ b/helm/ocaml/paramodulation/indexing.ml
@@ -1,8 +1,3 @@
-(* type naif_indexing =
-    (Cic.term * ((bool * Inference.equality) list)) list 
-;; *)
-
-type pos = Left | Right ;;
 
 let head_of_term = function
   | Cic.Appl (hd::tl) -> hd
@@ -10,6 +5,12 @@ let head_of_term = function
 ;;
 
 
+(*
+let empty_table () =
+  Hashtbl.create 10
+;;
+
+
 let index table eq =
   let _, (_, l, r, ordering), _, _ = eq in
   let hl = head_of_term l in
@@ -21,13 +22,13 @@ let index table eq =
   let _ = 
     match ordering with
     | Utils.Gt ->
-        index hl Left
+        index hl Utils.Left
     | Utils.Lt ->
-        index hr Right
-    | _ -> index hl Left; index hr Right
+        index hr Utils.Right
+    | _ -> index hl Utils.Left; index hr Utils.Right
   in
-(*   index hl Left; *)
-(*   index hr Right; *)
+(*   index hl Utils.Left; *)
+(*   index hr Utils.Right; *)
   table
 ;;
 
@@ -41,13 +42,22 @@ let remove_index table eq =
     let newentry = List.filter (fun e -> e <> (pos, eq)) x_entry in
     Hashtbl.replace table x newentry
   in
-  remove_index hl Left;
-  remove_index hr Right;
+  remove_index hl Utils.Left;
+  remove_index hr Utils.Right;
   table
 ;;
+*)
 
 
-let rec find_matches unif_fun metasenv context ugraph lift_amount term =
+let empty_table () =
+  Path_indexing.PSTrie.empty
+;;
+
+let index = Path_indexing.index
+and remove_index = Path_indexing.remove_index;;
+  
+
+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
@@ -55,70 +65,169 @@ let rec find_matches unif_fun metasenv context ugraph lift_amount term =
   let module HL = HelmLibraryObjects in
   let cmp = !Utils.compare_terms in
   let names = Utils.names_of_context context in
-  Printf.printf "CHIAMO find_matches (%s) su: %s\n"
-    (if unif_fun == Inference.matching then "MATCHING"
-     else if unif_fun == CicUnification.fo_unif then "UNIFICATION"
-     else "??????????")
-    (CicPp.pp term names);
   function
     | [] -> None
-    | (pos, (proof, (ty, left, right, o), metas, args))::tl ->
+    | candidate::tl ->
+        let pos, (proof, (ty, left, right, o), metas, args) = candidate in
         let do_match c other eq_URI =
-          Printf.printf "provo con %s: %s, %s\n\n"
-            (if unif_fun == Inference.matching then "MATCHING"
-             else if unif_fun == CicUnification.fo_unif then "UNIFICATION"
-             else "??????????")
-            (CicPp.pp term names)
-            (CicPp.pp (S.lift lift_amount c) names);
           let subst', metasenv', ugraph' =
-(*             Inference.matching (metasenv @ metas) context term *)
-(*               (S.lift lift_amount c) ugraph *)
-            unif_fun (metasenv @ metas) context
+            Inference.matching (metasenv @ metas) context
               term (S.lift lift_amount c) ugraph
           in
-(*           let names = U.names_of_context context in *)
-          Printf.printf "MATCH FOUND: %s, %s\n"
-            (CicPp.pp term names) (CicPp.pp (S.lift lift_amount c) names);
           Some (C.Rel (1 + lift_amount), subst', metasenv', ugraph',
-                (proof, ty, c, other, eq_URI))
+                (candidate, eq_URI))
         in
         let c, other, eq_URI =
-          if pos = Left then left, right, HL.Logic.eq_ind_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
-            print_endline "SONO QUI!";
-            let res = do_match c other eq_URI in
-            print_endline "RITORNO RES";
-            res
+            do_match c other eq_URI
           with e ->
-            Printf.printf "ERRORE!: %s\n" (Printexc.to_string e);
-            find_matches unif_fun metasenv context ugraph lift_amount term tl
+            find_matches metasenv context ugraph lift_amount term tl
         else
-          let res =
-            try
-              let res = do_match c other eq_URI in
-              print_endline "RITORNO RES 2";
-              res
-            with e -> None in
+          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
-              Printf.printf "c': %s\nother': %s\norder: %s\n\n"
-                (CicPp.pp c' names) (CicPp.pp other' names)
-                (U.string_of_comparison order);
-(*               if cmp (M.apply_subst s c) (M.apply_subst s other) = U.Gt then *)
               if order = U.Gt then
                 res
               else
-                find_matches unif_fun metasenv context ugraph
-                  lift_amount term tl
+                find_matches metasenv context ugraph lift_amount term tl
           | None ->
-              find_matches unif_fun metasenv context ugraph lift_amount term tl
+              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
+;;
+
+
+type retrieval_mode = Matching | Unification;;
+
+(*
+let get_candidates mode table term =
+  try Hashtbl.find table (head_of_term term) with Not_found -> []
+;;
+*)
+
+
+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 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
 ;;
 
 
@@ -127,14 +236,12 @@ let rec demodulate_term metasenv context ugraph table lift_amount term =
   let module S = CicSubstitution in
   let module M = CicMetaSubst in
   let module HL = HelmLibraryObjects in
-  let hd_term = head_of_term term in
-  let candidates = try Hashtbl.find table hd_term with Not_found -> [] in
+  let candidates = get_candidates Matching table term in
   match term with
   | C.Meta _ -> None
   | term ->
       let res =
-        find_matches Inference.matching metasenv context ugraph
-          lift_amount term candidates
+        find_matches metasenv context ugraph lift_amount term candidates
       in
       if res <> None then
         res
@@ -158,8 +265,8 @@ let rec demodulate_term metasenv context ugraph table lift_amount term =
             in (
               match res with
               | None -> None
-              | Some (_, subst, menv, ug, info) ->
-                  Some (C.Appl ll, subst, menv, ug, info)
+              | Some (_, subst, menv, ug, eq_found) ->
+                  Some (C.Appl ll, subst, menv, ug, eq_found)
             )
         | C.Prod (nn, s, t) ->
             let r1 =
@@ -173,33 +280,32 @@ let rec demodulate_term metasenv context ugraph table lift_amount term =
                   in (
                     match r2 with
                     | None -> None
-                    | Some (t', subst, menv, ug, info) ->
+                    | Some (t', subst, menv, ug, eq_found) ->
                         Some (C.Prod (nn, (S.lift 1 s), t'),
-                              subst, menv, ug, info)
+                              subst, menv, ug, eq_found)
                   )
-              | Some (s', subst, menv, ug, info) ->
-                  Some (C.Prod (nn, s', (S.lift 1 t)), subst, menv, ug, info)
+              | Some (s', subst, menv, ug, eq_found) ->
+                  Some (C.Prod (nn, s', (S.lift 1 t)),
+                        subst, menv, ug, eq_found)
             )
         | t ->
-(*             Printf.printf "Ne` Appl ne` Prod: %s\n" *)
-(*               (CicPp.pp t (Utils.names_of_context context)); *)
             None
 ;;
 
 
-let rec demodulate newmeta env table target =
+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
-  print_endline "\n\ndemodulate";
   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, (proof', ty, what, other, eq_URI)) = 
+  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 = S.subst (M.apply_subst subst other) t in
+      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] @
@@ -210,39 +316,49 @@ let rec demodulate newmeta env table target =
       M.apply_subst subst (C.Appl [C.Const (eq_URI, []); ty; what; t';
                                    proof; other; proof'])
     in
-    let newmeta, newtarget =
-      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)
+    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
-    newmeta, newtarget
+    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 then
-        newmeta, newtarget
+      if (Inference.is_identity (metasenv', context, ugraph) newtarget) ||
+        (Inference.meta_convertibility_eq target newtarget) then
+          newmeta, newtarget
       else
-        demodulate newmeta env table newtarget
+        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 then
-            newmeta, newtarget
+          if (Inference.is_identity (metasenv', context, ugraph) newtarget) ||
+            (Inference.meta_convertibility_eq target newtarget) then
+              newmeta, newtarget
           else
-            demodulate newmeta env table newtarget
+            if subsumption env table newtarget then
+              newmeta, build_identity newtarget
+            else
+              demodulation newmeta env table newtarget
       | None ->
           newmeta, target
 ;;
@@ -253,17 +369,43 @@ let rec betaexpand_term metasenv context ugraph table lift_amount term =
   let module S = CicSubstitution in
   let module M = CicMetaSubst in
   let module HL = HelmLibraryObjects in
-  let hd_term = head_of_term term in
-  let candidates = try Hashtbl.find table hd_term with Not_found -> [] in
+  let candidates = get_candidates Unification table term in
   let res, lifted_term = 
     match term with
     | C.Meta (i, l) ->
-        let l = 
-          List.map (function
-                      | Some t -> Some (S.lift lift_amount t)
-                      | None -> None) 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
-        [], C.Meta (i, l)
+        e, C.Meta (i, lifted_l)
           
     | C.Rel m ->
         [], if m <= lift_amount then C.Rel m else C.Rel (m+1)
@@ -276,12 +418,12 @@ let rec betaexpand_term metasenv context ugraph table lift_amount term =
             table (lift_amount+1) t in
         let l1' =
           List.map
-            (fun (t, s, m, ug, info) ->
-               C.Prod (nn, t, lifted_t), s, m, ug, info) l1
+            (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, info) ->
-               C.Prod (nn, lifted_s, t), s, m, ug, info) l2 in
+            (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 ->
@@ -293,35 +435,31 @@ let rec betaexpand_term metasenv context ugraph table lift_amount term =
                in
                let l1 =
                  List.map
-                   (fun (a, s, m, ug, info) -> a::lifted_tl, s, m, ug, info)
+                   (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, info) -> lifted_arg::r, s, m, ug, info)
+                     (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, info) -> (C.Appl l, s, m, ug, info)) l',
+        (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
-  | _ ->
-(*       let names = Utils.names_of_context context in *)
-(*       Printf.printf "CHIAMO find_matches su: %s\n" (CicPp.pp term names); *)
-      match
-        find_matches CicUnification.fo_unif metasenv context ugraph
-          lift_amount term candidates
-      with
-      | None -> res, lifted_term
-      | Some r ->
-(*           let _, _, _, _, (_, _, what, _, _) = r in *)
-(*           Printf.printf "OK, aggiungo a res: %s\n" (CicPp.pp what names); *)
-          r::res, lifted_term
+  | term ->
+      let r = 
+        find_all_matches metasenv context ugraph lift_amount term candidates
+      in
+      r @ res, lifted_term
 ;;
 
 
@@ -332,24 +470,16 @@ let superposition_left (metasenv, context, ugraph) table target =
   let module HL = HelmLibraryObjects in
   let module CR = CicReduction in
   let module U = Utils in
-  print_endline "\n\nsuperposition_left";
   let proof, (eq_ty, left, right, ordering), _, _ = target in
   let expansions, _ =
     let term = if ordering = U.Gt then left else right in
-    let res = 
-      betaexpand_term metasenv context ugraph table 0 term in
-(*     let names = U.names_of_context context in *)
-(*     Printf.printf "\n\nsuperposition_left: %s\n%s\n" *)
-(*       (CicPp.pp term names) *)
-(*       (String.concat "\n" *)
-(*          (List.map *)
-(*             (fun (_, _, _, _, (_, _, what, _, _)) -> CicPp.pp what names) *)
-(*             (fst res))); *)
-    res
+    betaexpand_term metasenv context ugraph table 0 term
   in
-  let build_new (bo, s, m, ug, (proof', ty, what, other, eq_URI)) =
+  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' = S.subst (M.apply_subst s other) bo in
+      let bo' = M.apply_subst s (S.subst other bo) in
       let bo'' =
         C.Appl (
           [C.MutInd (HL.Logic.eq_URI, 0, []);
@@ -358,18 +488,15 @@ let superposition_left (metasenv, context, ugraph) table target =
             else [S.lift 1 left; bo'])
       in
       let t' = C.Lambda (C.Anonymous, ty, bo'') in
-      S.subst (M.apply_subst s other) bo,
+      bo',
       M.apply_subst s
         (C.Appl [C.Const (eq_URI, []); ty; what; t';
                  proof; other; proof'])
     in
-    let left, right, newordering =
-      if ordering = U.Gt then
-        newgoal, right, !Utils.compare_terms newgoal right
-      else
-        left, newgoal, !Utils.compare_terms left newgoal
-    in
-    (newproof, (eq_ty, left, right, ordering), [], [])
+    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
 ;;
@@ -382,7 +509,6 @@ let superposition_right newmeta (metasenv, context, ugraph) table target =
   let module HL = HelmLibraryObjects in
   let module CR = CicReduction in
   let module U = Utils in
-  print_endline "\n\nsuperposition_right";
   let eqproof, (eq_ty, left, right, ordering), newmetas, args = target in
   let metasenv' = metasenv @ newmetas in
   let maxmeta = ref newmeta in
@@ -401,31 +527,34 @@ let superposition_right newmeta (metasenv, context, ugraph) table target =
         in
         (res left right), (res right left)
   in
-  let build_new ordering (bo, s, m, ug, (proof', ty, what, other, eq_URI)) =
+  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' = S.subst (M.apply_subst s other) bo in
+      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] @
+          [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
-      S.subst (M.apply_subst s other) bo,
+      bo',
       M.apply_subst s
         (C.Appl [C.Const (eq_URI, []); ty; what; t';
                  eqproof; other; proof'])
     in
     let newmeta, newequality = 
-      let left, right, newordering =
-        if ordering = U.Gt then
-          newgoal, right, !Utils.compare_terms newgoal right
-        else
-          left, newgoal, !Utils.compare_terms left newgoal
-      in
-      Inference.fix_metas !maxmeta
-        (newproof, (eq_ty, left, right, ordering), [], [])
+      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