anchor.diff:  check_is_callback_fun(Info, FunName, Arity)->
     case is_callback_fun(Info, FunName, Arity) of
       true -> 
  -      exit({error, "The refactorer does not support tupling "
  -                   "callback function parameters"});
  +      {error, "Tupling parameters of a callback function is not supported."};
       false -> ok
     end.
   
  
positive.code:                   FunPatterns = refac_syntax:clause_patterns(hd(Clause)),    
                    AppPar =  refac_syntax:application_arguments(AppNode),  
                    {Result, FunPatterns, AppNode, AppPar, FunNode};          
                  {error, _} -> 
                    exit({error, "The function definition can not locate"})
                end;
              {error, _} -> exit({error, " Bad position"})
            end;
          {error, _} -> 
            exit({error, "The selected expression can not locate"})
        end
    end.
  
  
negative.code: check_parameters(FirstPar, Number, Arity, FunPatterns, AppNode, AppPar) ->
      case (Number < 1) or (Number > Arity) of
        true ->
  	  {error,
  		"It is not possible to tuple " ++  integer_to_list(Number) ++ " parameters"};
        false ->
  	  case AppNode of
  	    [] -> search_par(FunPatterns, Number, FirstPar);
  