immediate.ref()

• 返回: <Immediate> immediate 的引用

当被调用时，只要 Immediate 活跃，请求 Node.js 事件循环不要退出。多次调用 immediate.ref() 不会有任何效果。

【When called, requests that the Node.js event loop not exit so long as the Immediate is active. Calling immediate.ref() multiple times will have no effect.】

默认情况下，所有 Immediate 对象都是被“引用”的，通常不需要调用 immediate.ref()，除非之前调用过 immediate.unref()。

【By default, all Immediate objects are "ref'ed", making it normally unnecessary to call immediate.ref() unless immediate.unref() had been called previously.】