用于遍历异步操作的集合

  1. const list = [ promise1, promise2, promise3 ]
  3. async function test () {
  4.     for await ( const item of list ) {
  5.         console.log(Date.now(), item)
  6.     }
  7. }

https://developer.mozilla.org/zh-CN/docs/Web/JavaScript/Reference/Statements/for-await…of
https://es6.ruanyifeng.com/#docs/async-iterator

部署接口

  1. const obj = {
  2.     i: 0,
  3.   [Symbol.asyncIterator] = function () {
  4.       return {
  5.         next: () => {
  6.         if (this.i < 3) {
  7.           return Promise.resolve({ value: this.i++, done: false })
  8.         }
  9.           return Promise.resolve({ done: true })
  10.       }
  11.     }
  12.   }
  13. }
  14. obj = function () {
  15.     return {
  16.     i: 0
  17.       next () {
  18.         return Promise.resolve({ value: this.i++, done: false })
  19.     }
  20.   }
  21. }