实现一个函数，执行该函数后，每隔 1s 在控制台打印从 0 开始递增的数字，直到打印 10 停止

解法1

  1. function printIncrement() {
  2.   const fn = function* () {
  3.     for(let i = 0; i <= 10; i++) {
  4.       yield i;
  5.     }
  6.   }
  8.   const num = fn();
  9.   const timer = setInterval(() => {
  10.     // value属性就是当前yield表达式的值
  11.     const value = num.next().value;
  13.     if(value <= 10) {
  14.       console.log(value);
  15.     } else {
  16.       clearInterval(timer);
  17.     }
  18.   }, 1000)
  19. }

解法2

  1. function printIncrement() {
  2.   let num = 0;
  3.   const fn = function* () {
  4.     console.log(num);
  6.     while(yield num++) {
  7.       console.log(num);
  8.     }
  9.   }
  11.   const counter = fn();
  12.   const timer = setInterval(() => {
  13.     if (num > 10) {
  14.       clearInterval(timer);
  15.     }
  17.     // yield表达式本身没有返回值，或者说总是返回undefined。next方法可以带一个参数，该参数就会被当作上一个yield表达式的返回值
  18.     counter.next(num <= 10);
  19.   }, 1000)
  20. }

解法3

  1. async function printIncrement() {
  2.   const fn = num => (
  3.     new Promise((resolve) => {
  4.       setTimeout(() => {
  5.         resolve(num)
  6.       }, 1000)
  7.     })
  8.   );
  10.   let num = 0;
  11.   while(num <= 10) {
  12.     console.log(await fn(num++))
  13.   }
  14. }