Canvas.CommandLineParsing.MainParser.GetMissingModeResult C# (CSharp) Метод

        private ParsingResult<IModeLauncher> GetMissingModeResult(IEnumerable<string> args, TextWriter standardWriter, TextWriter errorWriter)
        {
            string error = "Error: no mode specified";
            var baseOptionsResult = BaseOptionsParser.Parse(args);
            if (baseOptionsResult.Success)
            {
                if (HandleBaseOptions(baseOptionsResult.Result, standardWriter))
                    return ParsingResult<IModeLauncher>.SuccesfulResult(new NullModeLauncher());
            }
            else
            {
                error = baseOptionsResult.ErrorMessage;
            }

            errorWriter.WriteLine(error);
            errorWriter.WriteLine();
            ShowHelp(errorWriter);
            return ParsingResult<IModeLauncher>.FailedResult(error);
        }