docs: function unique(ar) {
    var a = []
      , i = -1
      , j
      , has;
    while (++i < ar.length) {
      j = -1;
      has = false;
      while (++j < a.length) {
        if (a[j] === ar[i]) {
          has = true;
          break;
        }
      }
      if (!has) { a.push(ar[i]); }
    }
    return a;
  }