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    core-js
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    3.15.1 • Public • Published

    core-js

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    Modular standard library for JavaScript. Includes polyfills for ECMAScript up to 2021: 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 -)

    core-js@3, babel and a look into the future

    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.

    Install

    npm i core-js

    DownloadsWeekly Downloads

    27,286,343

    Version

    3.15.1

    License

    MIT

    Unpacked Size

    742 kB

    Total Files

    1817

    Last publish

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