gistfile1.txt

<script>
  // First log 'start'
  // Then log "starting alpha"
  // Then, sleep for 2 seconds
  // Then, log 'alpha'
  // Then, log "starting beta"
  // Then, 4 seconds later, log beta
  // Then, log "starting gamma"
  // Then, 1 second later log gamma
  // Then, log "starting delta"
  // Then, 3 seconds later log delta
  console.log('start')
  function sleep (milliseconds) {
    return new Promise((resolve) => {
      setTimeout(() => {
        resolve()
      }, milliseconds)
    })
  }
  console.log('starting alpha')
  sleep(2000).then(() => {
    console.log('alpha')
    console.log('starting beta')
    return sleep(4000)
  }).then(() => {
    console.log('beta')
    console.log('starting gamma')
    return sleep(1000)
  }).then(() => {
    console.log('gamma')
    console.log('starting delta')
    return sleep(3000)
  }).then(() => {
    console.log('delta')
  })
</script>