@babel/runtime

What is @babel/runtime?

The @babel/runtime package is a library that includes Babel modular runtime helpers and a version of regenerator-runtime. It is used to avoid polluting the global scope and to reduce the size of the compiled output by deduplicating helper functions that are commonly used by Babel-transpiled code. It is particularly useful when building libraries or applications that need to be optimized for size and scope isolation.

What are @babel/runtime's main functionalities?

Modularized Helpers

This feature allows you to use Babel's helper functions in a modular way, without including them in every file that needs them, thus reducing redundancy and file size.

import _classCallCheck from '@babel/runtime/helpers/classCallCheck';

class MyClass {
  constructor() {
    _classCallCheck(this, MyClass);
    // class body
  }
}

Regenerator Runtime

Includes a version of the regenerator runtime to enable the use of async/await and generator functions in environments that do not natively support them.

import 'regenerator-runtime/runtime';

async function asyncCall() {
  await someAsyncFunction();
}

Other packages similar to @babel/runtime

core-js

Similar to @babel/runtime, core-js is a modular standard library for JavaScript, which includes polyfills for ECMAScript features. It is often used in conjunction with Babel to ensure that newer language features will work in older environments. It is more comprehensive than @babel/runtime but can lead to larger bundle sizes if not used carefully.

tslib

tslib is a runtime library for TypeScript that includes helper functions similar to those in @babel/runtime. It is used to support features from TypeScript such as async/await, spread operators, and others without duplicating code. It is specific to TypeScript, whereas @babel/runtime is used with Babel and can be used with JavaScript or TypeScript.

README

@babel/runtime

babel's modular runtime helpers

See our website @babel/runtime for more information.

Install

Using npm:

npm install --save @babel/runtime

or using yarn:

yarn add @babel/runtime

Changelog

v7.17.0 (2022-02-02)

:rocket: New Feature

• babel-cli, babel-core
  • #14065 Allow plugins/presets to indicate external dependencies (@nicolo-ribaudo)
• babel-core, babel-parser, babel-traverse
  • #14174 Expose .index on Position to internally track nodes location (@tolmasky)
• babel-generator, babel-parser, babel-plugin-proposal-pipeline-operator, babel-plugin-syntax-pipeline-operator
  • #13973 proposal-pipe: Add support for ^^ and @@ topics (@js-choi)
• babel-traverse
  • #13940 Add new method to check if node is null or not (@danez)
• babel-generator, babel-parser, babel-plugin-syntax-destructuring-private, babel-standalone
  • #13931 Parse destructuring private fields (@JLHwung)
• babel-helper-create-class-features-plugin, babel-helpers, babel-plugin-proposal-decorators, babel-plugin-syntax-decorators, babel-runtime-corejs2, babel-runtime-corejs3, babel-runtime, babel-standalone, babel-types
  • #14004 Add new decorators transform (@pzuraq)
• babel-generator, babel-parser, babel-traverse, babel-types
  • #13681 Add the decoratorsAutoAccessors parser plugin (@pzuraq)
• babel-core, babel-helper-create-regexp-features-plugin, babel-plugin-proposal-unicode-sets-regex, babel-plugin-syntax-unicode-sets-regex, babel-plugin-transform-dotall-regex
  • #14125 Add transform support for the "regexp unicode sets" proposal (@nicolo-ribaudo)
• babel-parser
  • #14086 Add parser support for the "regexp unicode sets" proposal (@nicolo-ribaudo)
• babel-register
  • #14087 Expose @babel/register/experimental-worker (@nicolo-ribaudo)

:bug: Bug Fix

• babel-parser
  • #14145 Reinterpret << when parsing TS type arguments (@JLHwung)
• babel-plugin-transform-runtime
  • #14187 Normalize absolute paths on Windows (@atti187)

:memo: Documentation

• #14223 Remove Babel 6 from SECURITY.md (@nicolo-ribaudo)

:house: Internal

• babel-helper-fixtures, babel-parser
  • #14201 Fuzz test location-related parser options (@tolmasky)
• babel-compat-data
  • #14208 Update compat data (specifically for rhino 1.7.14) (@phulin)
• Other
  • #14190 chore: run tscheck on babel 8 breaking test (@JLHwung)

:running_woman: Performance

• babel-cli, babel-core
  • #14209 Switch to @ampproject/remapping to merge source maps (@jridgewell)