1    sleep = (milliseconds) => {
2        return new Promise(resolve => setTimeout(resolve, milliseconds))
3    }
4	
5    componentDidUpdate(prevProps, prevState, snapshot) {
6            this.sleep(5000).then(r => {
7            // do something
8      	    })
9    }

1async function init() {
2  console.log(1);
3  await sleep(1000);
4  console.log(2);
5}
6
7function sleep(ms) {
8  return new Promise((resolve) => {
9    setTimeout(resolve, ms);
10  });
11}
12
13// one liner
14let sleep = ms => new Promise(resolve => setTimeout(resolve, ms));

1setTimeout(() => {  console.log("World!"); }, 2000);