Promise [](https://travis-ci.org/taylorhakes/promise-polyfill) ============= Lightweight promise polyfill for the browser and node. A+ Compliant. It is a perfect polyfill IE, Firefox or any other browser that does not support native promises. This implementation is based on [then/promise](https://github.com/then/promise). It has been changed to use the prototype for performance and memory reasons. For API information about Promises, please check out this article [HTML5Rocks article](http://www.html5rocks.com/en/tutorials/es6/promises/). It is extremely lightweight. ***< 1kb Gzipped*** ## Downloads - [Promise](https://raw.github.com/taylorhakes/promise-polyfill/master/Promise.js) - [Promise-min](https://raw.github.com/taylorhakes/promise-polyfill/master/Promise.min.js) ### Node ``` npm install promise-polyfill ``` ## Simple use ``` var prom = new Promise(function(resolve, reject) { // do a thing, possibly async, then… if (/* everything turned out fine */) { resolve("Stuff worked!"); } else { reject(new Error("It broke")); } }); // Do something when async done prom.then(function() { ... }); ``` ## Performance By default promise-polyfill uses `setImmediate`, but falls back to `setTimeout` for executing asynchronously. If a browser does not support `setImmediate`, you may see performance issues. Use a `setImmediate` polyfill to fix this issue. [setAsap](https://github.com/taylorhakes/setAsap) or [setImmediate](https://github.com/YuzuJS/setImmediate) work well. ## Testing ``` npm install npm test ``` ## License MIT