Run an array of promises in sequence

promise-seq.js

const results = []
return arrayOfPromises.reduce((chain, promise, i) =>
  chain.then((result) => {
  	if (i > 0) results[i-1] = result
  	return promise
  })
, Promise.resolve())
  .then((lastResult) => results.push(lastResult))
  .then(() => results)