X-Git-Url: http://matita.cs.unibo.it/gitweb/?a=blobdiff_plain;f=helm%2Fsoftware%2Fcomponents%2Fng_refiner%2FnCicUnification.ml;h=3000b7311dca621bcedfc3464380621c13d3e2a6;hb=e085135177f7b3b74b410d47a4f3bca1784b60b1;hp=d64fb005fe79805781ca0a79a10030d492ca2e8a;hpb=d174e54c365ab9df38367de9336c213a03be3c27;p=helm.git

diff --git a/helm/software/components/ng_refiner/nCicUnification.ml b/helm/software/components/ng_refiner/nCicUnification.ml
index d64fb005f..3000b7311 100644
--- a/helm/software/components/ng_refiner/nCicUnification.ml
+++ b/helm/software/components/ng_refiner/nCicUnification.ml
@@ -302,33 +302,34 @@ and unify hdb test_eq_only metasenv subst context t1 t2 =
                   unify hdb test_eq_only metasenv subst context term1 term2
               with NCicUtils.Subst_not_found _-> raise (UnificationFailure msg))
        
-       | NCic.Appl (NCic.Meta (i,l)::args), NCic.Meta (n, _) when 
-         not (NCicMetaSubst.flexible subst args) &&
-         is_locked n subst &&
-         not (List.mem_assoc i subst) 
-         ->
-           (* we verify that none of the args is a Meta, 
-              since beta expanding w.r.t a metavariable makes no sense  *)
-              let metasenv, lambda_Mj =
-                lambda_intros metasenv subst context t1 args
-              in
-              let metasenv, subst = 
-                unify hdb test_eq_only metasenv subst context 
-                  (C.Meta (i,l)) lambda_Mj
-              in
+       | _, NCic.Meta (n, _) when is_locked n subst ->
+           (let (metasenv, subst), i = 
+              match NCicReduction.whd ~subst context t1 with
+              | NCic.Appl (NCic.Meta (i,l)::args) when
+                  not (NCicMetaSubst.flexible subst args) 
+                ->
+                 let metasenv, lambda_Mj =
+                   lambda_intros metasenv subst context t1 args
+                 in
+                   unify hdb test_eq_only metasenv subst context 
+                    (C.Meta (i,l)) lambda_Mj,
+                   i
+              | NCic.Meta (i,_) -> (metasenv, subst), i
+              | _ -> assert false
+             in
               let t1 = NCicReduction.whd ~subst context t1 in
-              let i, l = 
-                match t1 with NCic.Meta (i,l) -> i, l | _ -> assert false
+              let j, lj = 
+                match t1 with NCic.Meta (j,l) -> j, l | _ -> assert false
               in
               let metasenv, subst = 
-                instantiate hdb test_eq_only metasenv subst context i l t2 true
+                instantiate hdb test_eq_only metasenv subst context j lj t2 true
               in
               (try
                 let name, ctx, term, ty = NCicUtils.lookup_subst i subst in
                 let term = eta_reduce subst term in
                 let subst = List.filter (fun (j,_) -> j <> i) subst in
                 metasenv, ((i, (name, ctx, term, ty)) :: subst)
-              with Not_found -> assert false)
+              with Not_found -> assert false))
 
        | C.Meta (n,lc), t -> 
            (try