docs: function(isSorted) {
      var result = [];
      var length = this.length;
  
      if (!length) {
        return result;
      }
  
      result[0] = this[0];
      var i = 1;
  
      if (isSorted) {
        for (; i < length; i++) {
          if (this[i] !== this[i - 1]) {
            result.push(this[i]);
          }
        }
      } else {
        for (; i < length; i++) {
          if (result.indexOf(this[i]) < 0) {
            result.push(this[i]);
          }
        }
      }
  
      return result;
    }