code: function TypedFastBitSet(iterable) {
    this.count = 0 | 0;
    this.words = new Uint32Array(8);
    if (isIterable(iterable)) {
      for (var key of iterable) {
        this.add(key);
      }
    }
  }
docs: you can provide an iterable an exception is thrown if typed arrays are not supported