Question 1

How to polyfill Promises in Internet Explorer?

Accepted Answer

Use ES6-Promise's auto-polyfill script via CDN; it automatically patches the Promise global and includes workarounds for IE's reserved keywords like 'catch', making it work out-of-the-box.

Question 2

ES6-Promise vs native Promises performance?

Accepted Answer

Native Promises are faster since they're built into the browser. ES6-Promise, as a polyfill, adds a slight performance overhead, so it's best used only when native support is absent or broken.

Question 3

How to use ES6-Promise in a Node.js project?

Accepted Answer

Install via npm, then require and call polyfill: `require('es6-promise').polyfill();` or use `require('es6-promise/auto');` for automatic patching, ensuring Promises are available globally.

Question 4

Does ES6-Promise work with async/await?

Accepted Answer

Yes, async/await relies on Promises, so ES6-Promise provides the necessary implementation. However, you'll still need to transpile async/await syntax separately if the environment doesn't support it.

Question 5

ES6-Promise or Bluebird for legacy support?

Accepted Answer

ES6-Promise is lighter and strictly ES6-compliant, ideal for minimal polyfilling. Bluebird offers more features and better performance but is larger; choose based on whether you need extras like cancellation vs. bundle size.

Question 6

What's the minified size of ES6-Promise?

Accepted Answer

The minified auto-polyfill version is about 6.19 KB (2.4 KB gzipped), making it one of the smallest Promise polyfills available, suitable for performance-conscious projects.

Question 7

How to auto-polyfill Promises in the browser without code changes?

Accepted Answer

Include the es6-promise.auto.js script from a CDN; it automatically detects and patches the global Promise object if missing or broken, requiring no additional configuration.

es6-promise

What is es6-promise?

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