code: function mixkey(seed, key) {
    var stringseed = seed + '', smear, j = 0;
    while (j < stringseed.length) {
      key[mask & j] =
        mask & ((smear ^= key[mask & j] * 19) + stringseed.charCodeAt(j++));
    }
    return tostring(key);
  }
docs: mixkey() Mixes a string seed into a key that is an array of integers, and returns a shortened string seed that is equivalent to the result key.