promise catch

promise_catch.js

const sleep = (fn, d = 500, fail = '') => new Promise((resolve, reject) => {
  setTimeout(() => {
    if(fail.length) {
         reject(fail)
         return
    } else {
        resolve(fn())
    }
    
  }, d)
})


const main = async function() {
     console.log(await sleep(() => 1))
     console.log(await sleep(() => 2, 1000, '姜鹏很帅'))
     console.log(await sleep(() => 3))
}
try{
    main()
}catch(e) {
  console.log(e)
}