anchor.diff:     * values are received. Multiple filters on a socket connection are allowed.
      */
     Future<Reply> filter(String eventHeader, String valueToFilter,
  -      {int timeoutSeconds: 10}) =>
  -      this._subscribeAndSendCommand(
  -          'filter $eventHeader $valueToFilter',
  +          {int timeoutSeconds: 10}) =>
  +      this._subscribeAndSendCommand('filter $eventHeader $valueToFilter',
             new Duration(seconds: timeoutSeconds));
   
     /**
  
positive.code:    */
    Future<Reply> linger({int timeoutSeconds: 10}) =>
        this._subscribeAndSendCommand(
            'linger',
            new Duration(seconds: timeoutSeconds));
  
  
    /**
     * Disable socket lingering. See linger above.
     */
    Future<Reply> nolinger({int timeoutSeconds: 10}) =>
        this._subscribeAndSendCommand(
            'nolinger',
            new Duration(seconds: timeoutSeconds));
  
    /**
     * Subscribe the socket to [events], which will be pumped into the
     * [eventStream].
     */
    Future<Reply> event(List<String> events, {String format: '',
        int timeoutSeconds: 10}) {
      if (!EventFormat.supportedFormats.contains(format)) {
        return new Future.error(
            new UnsupportedError(
                'Format "$format" unsupported. Supported formats are: '
                    '${EventFormat.supportedFormats.join(', ')}'));
      }
  
      return this._subscribeAndSendCommand(
          'event ${format} ${events.join(' ')}',
          new Duration(seconds: timeoutSeconds));
    }
  
  
negative.code:  * FreeSWTICH event socket connection.
   */
  class Connection {
    final Logger log = new Logger(libraryName);
  
    Socket _socket = null;
  