The @babel/plugin-transform-for-of package is a plugin for Babel, a JavaScript compiler, that transforms for...of loops into more compatible ES5 syntax. This is particularly useful for ensuring that your JavaScript code can run in environments that do not support the latest ECMAScript features, such as older browsers. The transformation helps in converting iterable objects in a way that can be understood by environments without native support for the for...of loop.

What are @babel/plugin-transform-for-of's main functionalities?

Transform for...of loops to ES5

This feature automatically converts for...of loops into a compatible ES5 syntax using simple iteration over arrays. This is useful for ensuring compatibility with older JavaScript environments.

"use strict";

var _arr = [1, 2, 3];

for (var _i = 0; _i < _arr.length; _i++) {
  var i = _arr[_i];
  console.log(i);
}

Optionally use loose mode for simpler output

In loose mode, the transformation is even simpler, avoiding the use of iterators altogether and directly accessing array elements by index. This results in faster code but assumes the iterated object is an array.

"use strict";

var _arr = [1, 2, 3];

for (var i = 0; i < _arr.length; i++) {
  console.log(_arr[i]);
}

Other packages similar to @babel/plugin-transform-for-of

Changelog

Source

v7.23.6 (2023-12-11)

:eyeglasses: Spec Compliance

babel-generator, babel-parser, babel-types
- #16154 Remove TSPropertySignature.initializer (@fisker)
babel-helpers, babel-plugin-proposal-decorators, babel-plugin-transform-class-properties, babel-plugin-transform-class-static-block, babel-plugin-transform-runtime, babel-preset-env, babel-runtime-corejs2, babel-runtime-corejs3, babel-runtime, babel-types
- #16139 Apply toPropertyKey on decorator context name (@JLHwung)

:bug: Bug Fix

babel-generator
- #16166 fix: Correctly indenting when retainLines is enabled (@liuxingbaoyu)
babel-helpers, babel-plugin-proposal-explicit-resource-management
- #16150 using: Allow looking up Symbol.dispose on a function (@odinho)
babel-plugin-proposal-decorators, babel-plugin-transform-class-properties
- #16161 Ensure the [[@@toPrimitive]] call of a decorated class member key is invoked once (@JLHwung)
- #16148 Support named evaluation for decorated anonymous class exp (@JLHwung)
babel-plugin-transform-for-of, babel-preset-env
- #16011 fix: for of with iterableIsArray and shadowing variable (@liuxingbaoyu)
babel-helpers, babel-plugin-proposal-decorators, babel-runtime-corejs2, babel-runtime-corejs3, babel-runtime
- #16144 Set function name for decorated private non-field elements (@JLHwung)
babel-plugin-transform-typescript
- #16137 Fix references to enum values with merging (@nicolo-ribaudo)

:microscope: Output optimization

babel-helper-create-class-features-plugin, babel-plugin-transform-class-properties
- #16159 Reuse computed key memoiser (@JLHwung)
babel-helpers, babel-plugin-proposal-decorators
- #16160 Optimize decorator helper size (@liuxingbaoyu)

Readme

Source