对Promise知识的一些文章整理，及其手写实现，加深自己的理解

我的手写Promise代码

Codesandbox 预览 (opens new window) stackblitz 预览 (opens new window)

Promise相关API

• Promise/A+
• then
• catch
• finally
• resolve
• reject
• all
• race
• any
• allSettled

手写Promise

• 完全理解并实现Promise（收藏） (opens new window)
• 一步一步手写完美符合PromiseA+规范的Promise (opens new window)
• 手写 Promise 全家桶 + Generator + async/await (opens new window)
• 这次彻底搞懂 Promise(手写源码多注释篇) (opens new window)
• Promise/async/Generator实现原理解析 (opens new window)

Promise面试题

• ES6之Promise常见面试题 (opens new window)
• 来45道Promise面试题一次爽到底(1.1w字用心整理) (opens new window)

输出结果题

1. 输出执行结果

function f() {
  setTimeout(() => {
    console.log(5)
    Promise.resolve().then(() => {
      console.log(6)
    })
  })
  new Promise((resolve,reject) => {
    console.log(1)
    resolve()
  }).then(() => {
    console.log(2)
    Promise.resolve().then(() => {
      console.log(3)
    })
    setTimeout(() => {
      console.log(4)
    })
    Promise.resolve().then(() => {
      console.log(7)
    })
  })
  Promise.resolve().then(() => {
    console.log(8)
  })
}

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