core-js

Modular standard library for JavaScript. Includes polyfills for ECMAScript 5, 2015, 2016, 2017: promises, symbols, collections, iterators, typed arrays, many other features, ECMAScript proposals, some cross-platform WHATWG / W3C ECMAScript-related features and proposals like setImmediate. You can load only required features or use it without global namespace pollution.

Example:

import 'core-js'; // <- at the top of your entry point

Array.from(new Set([1, 2, 3, 2, 1]));          // => [1, 2, 3]
[1, [2, 3], [4, [5]]].flatten(2);              // => [1, 2, 3, 4, 5]
Promise.resolve(32).then(x => console.log(x)); // => 32

You can load only required features:

import 'core-js/features/array/from';    // <- at the top of your entry point
import 'core-js/features/array/flatten'; // <- at the top of your entry point
import 'core-js/features/set';           // <- at the top of your entry point
import 'core-js/features/promise';       // <- at the top of your entry point

Array.from(new Set([1, 2, 3, 2, 1]));          // => [1, 2, 3]
[1, [2, 3], [4, [5]]].flatten(2);              // => [1, 2, 3, 4, 5]
Promise.resolve(32).then(x => console.log(x)); // => 32

Or use it without global namespace pollution:

import from from 'core-js-pure/features/array/from';
import flatten from 'core-js-pure/features/array/flatten';
import Set from 'core-js-pure/features/set';
import Promise from 'core-js-pure/features/promise';

from(new Set([1, 2, 3, 2, 1]));                // => [1, 2, 3]
flatten([1, [2, 3], [4, [5]]], 2);             // => [1, 2, 3, 4, 5]
Promise.resolve(32).then(x => console.log(x)); // => 32

It's a global version (first 2 examples), for more info see core-js documentation.

Current Tags

4.0.0-alpha.0 ... alpha (9 months ago)
3.0.0-beta.20 ... beta (6 years ago)
3.39.0 ... latest (15 days ago)

core-js

Current Tags

276 Versions