text: /**
   * Keep the first *n* items of the array. If *n* is negative, keep the last *-n* items.
   * @arguments _(n)_
   * @example
   *  [1, 2, 3, 4, 5].keep( 3); // => [ 1, 2, 3 ]
   *  [1, 2, 3, 4, 5].keep(-3); // => [ 3, 4, 5 ]
   */
  sc.define("keep", {
    Array: function(n) {
      n |= 0;
      if (n < 0) {
        return this.slice(this.length + n);
      } else {
        return this.slice(0, n);
      }
    }
  });
  