问题描述
我的理解是，在每个宏任务之后 处理完整的微任务任务队列。
My understanding is that the full microtask task queue is processed after each macrotask.
如果是这种情况，为什么 JavaScript Promise 微任务之后，将执行code> setTimeout 回调c>？
If that is the case, why does the setTimeout callback get executed after the Promise microtasks in the following snippet of JavaScript?
console.log('start');
setTimeout(() => {
console.log("setTimeout");
});
Promise.resolve().then(function() {
console.log('promise');
});
console.log('end');
这将输出以下内容：
> "start"
> "end"
> "promise"
> "setTimeout"
是因为〜 4ms 现代浏览器带来的延迟？
Is it because of a ~4ms delay imposed by modern browsers?
来自：
Though this states that it is only true for successive callback nesting.
推荐答案
是。以及您运行的代码，从 console.log（'start'）到 console.log（'end'），就是这样的宏任务。运行完毕后，将处理带有promise回调的微任务队列，只有在下一个宏任务（超时）开始运行之后。
Yes. And the code that you ran, from console.log('start') to console.log('end'), is such a macrotask. After it ran to completion, the microtask queue with the promise callbacks is processed, and only after that the next macrotask (the timeout) gets to run.
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