anchor.diff:                               H1Sub = create_sub(H1, lists:sublist(List2, I)),
                                Res=list_unification_1(T1, lists:nthtail(I, List2)),
                                combine_unification_results(H1Sub, Res)
  -                         end||I<-lists:seq(0,Len2-Len1)],
  +                         end||I<-lists:seq(1,Len2-Len1)],
                       lists:append(Res)
               end;
           false ->
  
positive.code:         true ->
              list_unification_3(Exp1, Exp2)
      end.
  
  has_meta_list(NodeList) ->
      [E ||E<-NodeList, is_meta_list(E)]/=[].
  
negative.code:                                         is_meta_meta_list_variable(B);  
                                  _ -> false
                              end;
                           [G] -> %% temporay fix.
                              case Body of 
                                  [B] ->
                                      is_meta_meta_list_variable(G) andalso
                                          is_meta_meta_list_variable(B);  
                                  _ -> false
                              end;
                          _ -> false
                      end;
                  _ ->
  