微任务，宏任务

[wuweijia]

微任务，宏任务

思考下面的代码

setTimeout(function () {
    console.log(1);
});

new Promise(function(resolve,reject){
    console.log(2)
    resolve(3)
}).then(function(val){
    console.log(val);
})

[wuweijia]

// 加入  nextTick()的回调函数
process.nextTick(function () { 
console.log('nextTick  执行1'); });
process.nextTick(function () { 
  console.log('nextTick  执行2');
});  // 加入  setImmediate()的回调函数
setImmediate(function () {
  console.log('setImmediate  执行1'); // 进入  循环
  process.nextTick(function () {
    console.log('拦截');
  });
});
setImmediate(function () {
console.log('setImmediate  执行2'); });
console.log('正常执行');

正常执行
nextTick  执行1 
nextTick  执行2 
setImmediate  执行1 
拦截
setImmediate  执行2

[wuweijia]

建议阅读 https://github.com/wuweijia/wuweijia.github.io/issues/51