code: function ArrayStream(arr, options) {
      var self = this;
      this._reading = false;
      this._closing = false;
      this._index = 0;
      options = options || {};
      this._duplex = options.duplex || false;
  
      this.set(arr);
  
      Duplex.call(this, {
          objectMode: true,
          highWaterMark: options.highWaterMark || Math.pow(2, 10)
      });
  }
docs: @constructor
  
  @param  {Array}  arr     (optional) Array to stream
  @param  {Object} options {duplex: false}