X-Git-Url: http://matita.cs.unibo.it/gitweb/?a=blobdiff_plain;f=matita%2Fcomponents%2Fng_tactics%2FnDestructTac.ml;h=be991484079afe4510396a93d27bde7d237f55cc;hb=e4328c9691fa85434acfb24eaedcb15ea2263b28;hp=c9e46dc2af1b8523109f4b594705afb33c7435f7;hpb=432d0f324b7246c91f20545867c0da4bd25f588e;p=helm.git

diff --git a/matita/components/ng_tactics/nDestructTac.ml b/matita/components/ng_tactics/nDestructTac.ml
index c9e46dc2a..be9914840 100644
--- a/matita/components/ng_tactics/nDestructTac.ml
+++ b/matita/components/ng_tactics/nDestructTac.ml
@@ -471,7 +471,9 @@ let subst_tac ~context ~dir skip cur_eq =
       | _ -> cascade_select_in_ctx status ~subst:(get_subst status) context skip cur_eq in
     let varname = match var with
       | NCic.Rel var -> 
-          let name,_ = List.nth context var in [name]
+          let name,_ = List.nth context (var+cur_eq-1) in
+	  HLog.warn (Printf.sprintf "destruct: trying to remove variable: %s" name);
+	  [name]
       | _ -> []
     in      
     let names_to_gen = List.filter (fun n -> n <> eq_name) names_to_gen in
@@ -495,7 +497,7 @@ let subst_tac ~context ~dir skip cur_eq =
                  (* XXX: temo che la clear multipla funzioni bene soltanto se
                   * gli identificatori sono nell'ordine giusto.
                   * Per non saper né leggere né scrivere, usiamo due clear
-                  * invece di una *)		   
+                  * invece di una *)
                  NTactics.try_tac (NTactics.clear_tac [eq_name]);
 		 NTactics.try_tac (NTactics.clear_tac varname);
 ]@