复制
1async function async1() {
2  console.log("async1 start");
3  await async2();
4  console.log("async1 end");
5}
6async function async2() {
7  setTimeout(() => {
8    console.log('timer')
9  }, 0)
10  console.log("async2");
11}
12async1();
13console.log("start")
14