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core-js

> Modular standard library for JavaScript. Includes polyfills for ECMAScript up to 2019: promises, symbols, collections, iterators, typed arrays, many other features, ECMAScript proposals, some cross-platform WHATWG / W3C features and proposals like `URL`. You can load only required features or use it without global namespace pollution.

# As advertising: the author is looking for a good job -)

# <a href="https://github.com/zloirock/core-js/tree/master/docs/2019-03-19-core-js-3-babel-and-a-look-into-the-future.md">core-js@3, babel and a look into the future</a>

# Raising funds

`core-js` isn't backed by a company, so the future of this project depends on you. Become a sponsor or a backer on Open Collective or on Patreon if you are interested in `core-js`.

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]]].flat(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/flat'; // <- 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]]].flat(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 flat from 'core-js-pure/features/array/flat';
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]
flat([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.**