异步任务的变量范围是什么？

var itemIds, result, taskQueue, _i, _len;
itemIds = [];
taskQueue = async.queue(function(task, callback) {
  console.log('Hello ' + task.name);
  return callback();
}, 10);
for (_i = 0, _len = results.length; _i < _len; _i++) {
  result = results[_i];
  taskQueue.push({}, function(err) {
    var item;
    item = new Item(result);
    return item.save(function(err, new_item) {
      itemIds[itemIds.length] = new_item._id;
      console.log(new_item._id);
      return console.log(itemIds);
    });
  });
}
taskQueue.drain = function() {
  console.log('Queue Done!');
  return console.log(itemIds.length);
};
var itemIds, result, taskQueue, _i, _len;
itemI