ToXmlCommand constructor Null safety



ToXmlCommand() : super('to_xml', 'Put localization from source to xml') {
      abbr: 'f',
      help: 'Source to export string for translation to xml.',
      valueHelp: 'SOURCE',
      allowed: [
      allowedHelp: {
        _sourceArb: 'Export from project arb files.',
        _sourceJson: 'Export from JSON (server localization). '
            'Require parameter $_argSource',
        _sourceIos: 'Export from .strings iOS localization files. '
            'All not empty files for all projects will be exported.',
      defaultsTo: _sourceArb,
      abbr: 's',
      help: 'Directory of source localization files. '
          'Supported by sources: $_sourceJson',
      valueHelp: 'DIR_PATH',
      abbr: 'l',
      help: 'Locale to export. By default this is '
          'base_locale_for_xml from alex configuration.',
      valueHelp: 'DIR_PATH',