The missing Promise helpers your project needs—just contains a few helpers that can benefit your project. Ships as an ES module.

Requires a native implementation of Promise (maybe a polyfill will work too), and support for async and await. You might be able to transpile these requirements away for older browsers.

Usage

Add to your dependencies via NPM or Yarn.

import * as promises from './node_modules/promiseslib/index.js';  // or
import * as promises from 'promiseslib';  // maybe, but must be transpiled

If you're feeling lazy, open this file in RawGit and use the latest production link. This won't provide you with updates but it is easy to include whole "https://..." paths via ES modules.

Methods

• promises.sleep(ms): builds a Promise which resolves after a specified time (or a frame if negative, or microtask if null/undefined is passed)

• promises.event(target, event): builds a Promise which resolves when the given event occurs

• promises.dedup(fn, ms): builds a dedup function which delays calls until the last in the specified period, all calls return the same shared Promise representing the completion of the last call

• promises.makeSingle(generator): converts a generator (that yields Promise instances) into a task that can only run at most once (read more)

• promises.group(callback): builds a wait group; aka a function which, when called with a Promise, returns a new Promise that waits for all passed promises to complete before resolving