Immediately invoked pify
npm install --save pificonst pifi = require('pifi')
const fs = require('fs')
async function main () {
console.log('Reading readme.md in 5 seconds')
await pifi(cb => setTimeout(cb, 5000))
console.log('Readind readme.md now')
const content = await pifi(cb => fs.readFile('readme.md', cb))
console.log('readme.md contains:', content)
}Immediately invoke fn with a node-style callback, and return a promise that settles when the callback is called.