code: function isSpecial(key) {
      if (key.length > 1) {
          return !!exports.specialKeys.filter(function (specialKey) {
              var pattern = new RegExp("^(" + specialKey + ")(:(\\d+(\\.\\d+)?))?$", 'g');
              return pattern.test(key);
          }).length;
      }
      return false;
  }
docs: Helper function to determine if given key is special or not.
  
  @param {string}  key
  @returns {boolean}