Array Unique

unique.js

Array.prototype.unique = function() {
  var a, i, j, l;
  a = [];
  l = this.length;
  i = 0;
  while (i < l) {
    j = i + 1;
    while (j < l) {
      if (this[i] === this[j]) {
        j = ++i;
      }
      j++;
    }
    a.push(this[i]);
    i++;
  }
  return a;
};