code: function put(item, force) {
  				if (!callback) {
  						if (max >= 0 && q.length >= max && !force) return false;
  						q.push(item);
  					} else {
  						var cb = callback;
  						callback = null;
  						exports.setImmediate(function () {
  							cb(err, item);
  						});
  					}
  				return true;
  			}
docs: /   `ok = q.put(data)`: queues an item synchronously. Returns true if the queue accepted it, false otherwise.