The @babel/runtime-corejs3 package is a runtime library for Babel that includes polyfills for ECMAScript features using core-js version 3. It is used alongside Babel to enable the use of new JavaScript features in environments that do not natively support them. This package helps to avoid polluting the global scope and reduces the size of the compiled code by deduplicating helper functions.

What are @babel/runtime-corejs3's main functionalities?

Polyfilling ECMAScript features

This code imports polyfills for stable ECMAScript features and the regenerator runtime needed to use generators and async functions.

import 'core-js/stable';
import 'regenerator-runtime/runtime';

Usage of built-in methods

This code demonstrates how to use the map method from core-js through the runtime without polluting the global Array prototype.

import { map } from '@babel/runtime-corejs3/core-js-stable/instance/map';

let arr = [1, 2, 3];
let mapped = map.call(arr, x => x * x);

Usage of new syntax features

This code shows how to use the helpers provided by @babel/runtime-corejs3 to work with new syntax features like async functions and generators.

import _asyncToGenerator from '@babel/runtime-corejs3/helpers/asyncToGenerator';
import _regeneratorRuntime from '@babel/runtime-corejs3/regenerator';

const asyncFunc = _asyncToGenerator(function* () {
  yield Promise.resolve('Hello World');
});

Other packages similar to @babel/runtime-corejs3

Changelog

Source

v7.18.9 (2022-07-18)

:bug: Bug Fix

babel-plugin-transform-modules-systemjs, babel-types
- #14763 fix: allow exporting TSDeclareFunction as default (@zxbodya)
babel-generator
- #14758 fix: returnType with comments generates incorrect code (@liuxingbaoyu)

:nail_care: Polish

babel-cli
- #14748 Print a message when the watcher of babel-cli is ready. (@liuxingbaoyu)

:house: Internal

babel-core, babel-helper-remap-async-to-generator, babel-helpers, babel-parser, babel-plugin-transform-block-scoping, babel-preset-env
- #13414 Prepare for compiling Babel to native ESM (@nicolo-ribaudo)
babel-helper-create-class-features-plugin, babel-helper-member-expression-to-functions, babel-helper-remap-async-to-generator, babel-helper-replace-supers, babel-helper-wrap-function, babel-helpers, babel-plugin-bugfix-v8-spread-parameters-in-optional-chaining, babel-plugin-proposal-decorators, babel-plugin-proposal-object-rest-spread, babel-plugin-proposal-optional-chaining, babel-plugin-transform-block-scoping, babel-plugin-transform-classes, babel-traverse, babel-types
- #14739 Provide better parentPath typings (@JLHwung)

:running_woman: Performance

babel-generator
- #14701 perf: Improve generator perf (@liuxingbaoyu)

Readme

Source