1. 简易版
  1. class AsyncQueue {
  2.   constructor() {
  3.     this.queue = []
  4.     this.index = 0
  5.   }
  7.   add(...fn) {
  8.     this.queue.push(...fn)
  9.   }
  11.   run() {
  12.     const fn = this.queue[this.index]
  13.     fn(this.next.bind(this))
  14.   }
  16.   next() {
  17.     if (this.index >= this.queue.length - 1) return
  18.     const fn = this.queue[++this.index]
  19.     fn(this.next.bind(this))
  20.   }
  21. }

参考资料