代码如下

setTimeout(() => {  console.log('timeout1')  Promise.resolve().then(()=>{		console.log('reslove1')	})}, 0)setTimeout(() => {  console.log('timeout2')  Promise.resolve().then(()=>{		console.log('reslove2')	})}, 0)setImmediate(()=>{	console.log('setImmediate1')})setImmediate(()=>{	console.log('setImmediate2')})Promise.resolve('resolve3').then((data)=>{    console.log(data)})复制代码

输出结果如下:

由于settimeout在timers阶段执行顺序不确定，按我的理解，结果有两种

1.settimeout在当前事件循环执行,输出结果:

'timeout1'>'timeout2'>'resolve3'>'resolve1'>'resolve2'>'setImmediate1'>'setImmediate2'复制代码

2.settimeout在下一个事件循环执行,输出结果:

'resolve3'>'setImmediate1'>'setImmediate2'>'timeout1'>'timeout2'>'resolve1'>'resolve2'复制代码

为何最后结果为,并且结果很稳定:

'resolve3'>'timeout1'>'timeout2'>'resolve1'>'resolve2'>'setImmediate1'>'setImmediate2'复制代码

去掉promise之后,输出结果为

求各位大牛指教下！！！谢谢！！！