用 Promise 封装一个 Deferred

[bravf]

const Deferred = () => {
  let resolve
  let reject

  const promise = new Promise( (_resolve, _reject) => {
    resolve = _resolve
    reject = _reject
  } )

  return {
    promise,
    resolve,
    reject,
  }
}

const defer = Deferred()

defer.promise.then( data => {
  console.log(data)
})
.catch( err => {
  console.error(err)
})

defer.resolve('hello')
defer.reject('request error')