1. //Promise
    2. const sleep = time => {
    3.   return new Promise(resolve => setTimeout(resolve,time))
    4. }
    5. sleep(1000).then(()=>{
    6.   console.log('sleep')
    7. })
    9. //Generator
    10. function* sleepGenerator(time) {
    11.   yield new Promise(function(resolve,reject){
    12.     setTimeout(resolve,time);
    13.   })
    14. }
    15. sleepGenerator(1000).next().value.then(()=>{  console.log('sleep')})
    17. //async
    18. function sleep(time) {
    19.   return new Promise(resolve => setTimeout(resolve,time))
    20. }
    21. async function output() {
    22.   let out = await sleep(1000);
    23.    console.log('sleep')
    24.   return out;
    25. }
    26. output();
    28. //ES5
    29. function sleep(callback,time) {
    30.   if(typeof callback === 'function')
    31.     setTimeout(callback,time)
    32. }
    34. function output(){
    35.   console.log('sleep');
    36. }
    37. sleep(output,1000);