code: function (config) {
      Filter.call(this);
      config = config || {};
  
      this.regex = config.regex || '';
      if (utils.isString(this.regex)) {
        this.regex = new RegExp(this.regex);
      }
  
      this.onMatch = config.match || config.onMatch || 'neutral';
      this.onMismatch = config.mismatch || config.onMismatch || 'deny';
    }
docs: Definition of the RegexFilter class.
  
  @constructor
  @param {Object} config Filter configuration. Possible configuration keys:
  - regex: The regular expression to use. String or RegExp. Required.
  - match: Decision to take when the event matches the regexp. String.
  Default value is "accept".
  - mismatch: Decision to take when the event does not match the regexp.
  String. Default value is "neutral".