anchor.diff:      end
     catch
       E1:E2 ->
  -      {error, {E1,E2}}
  +      {error, gui_str:format("~p:~p~n~p", [E1, E2, erlang:get_stacktrace()])}
     end.
   
   %%--------------------------------------------------------------------
  
positive.code: %% @end
  %%--------------------------------------------------------------------
  -spec prepare_to_write(Input :: term()) -> tuple().
  prepare_to_write(Input) when is_list(Input) ->
    {struct, lists:map(fun(I) -> prepare_to_write(I) end, Input)};
  
  prepare_to_write({K, V}) when is_list(V) ->
    {K, prepare_to_write(V)};
  
  prepare_to_write({K, V}) ->
    {K, V}.
negative.code: 
  %%--------------------------------------------------------------------
  %% @doc
  %% Executes test configuration many times. Returns [ValuesSums, ValuesLists, OkNum, Errors].
  %% @end
  %%--------------------------------------------------------------------
  -spec exec_multiple_tests(M :: atom(), F :: atom(), Inputs :: list(), Count :: integer()) -> list().
  exec_multiple_tests(M, F, Inputs, Count) ->
    exec_multiple_tests(M, F, Inputs, Count, [], [], 0, []).
  
  exec_multiple_tests(_M, _F, _Inputs, 0, ValuesSums, ValuesLists, OkNum, Errors) ->
    ReversedValuesLists = lists:map(fun({K, Val}) ->
      {K, lists:reverse(Val)}
    end, ValuesLists),
    [ValuesSums, ReversedValuesLists, OkNum, lists:reverse(Errors)];
  
  exec_multiple_tests(M, F, Inputs, Count, ValuesSums, ValuesLists, OkNum, Errors) ->
    case exec_test(M, F, Inputs) of
      {error, E} ->
        exec_multiple_tests(M, F, Inputs, Count - 1, ValuesSums, ValuesLists, OkNum, [E | Errors]);
      V ->
        case ValuesSums of
          [] ->
            InitValuesLists = lists:map(fun({K, Val}) ->
              {K, [Val]}
            end, V),
            exec_multiple_tests(M, F, Inputs, Count - 1, V, InitValuesLists, OkNum + 1, Errors);
          _ ->
            NewVSums = lists:zipwith(fun({K, V1}, {K, V2}) ->
              {K, V1 + V2}
            end, V, ValuesSums),
            NewVLists = lists:zipwith(fun({K, V1}, {K, V2}) ->
              {K, [V1 | V2]}
            end, V, ValuesLists),
            exec_multiple_tests(M, F, Inputs, Count - 1, NewVSums, NewVLists, OkNum + 1, Errors)
        end
    end.
  
  