babel-plugin-transform-jscript

6.22.0 verified Sat Apr 25 auth: no javascript deprecated

Babel plugin that fixes buggy named function expressions in JScript (IE<=8). This is an older Babel 6 plugin (v6.22.0), part of Babel's preset-es2015. It wraps named function expressions in an IIFE to avoid JScript's incorrect hoisting behavior. Not needed for modern browsers or Node.js. The plugin has no active maintenance as Babel 6 is superseded by Babel 7+; alternatives include using @babel/preset-env with the 'ie' target.

Common errors

error Cannot find module 'babel-plugin-transform-jscript' ↓

cause Package not installed or Babel 7+ is used (plugin name changed).

fix

Run 'npm install babel-plugin-transform-jscript' for Babel 6, or use @babel/plugin-transform-jscript for Babel 7+ (if available) but it's likely not needed.

error Error: Cannot find module 'babel-core' from '...' ↓

cause Using Babel 6 API with Node API but babel-core not installed.

fix

Ensure 'babel-core' is installed: npm install babel-core

Warnings

deprecated This plugin is for Babel 6 only and is no longer maintained. Use @babel/preset-env with the 'ie' option instead. ↓

fix Upgrade to Babel 7+ and use @babel/preset-env targeting 'ie 8' or similar.

gotcha The plugin only transforms named function expressions with the 'var' assignment pattern. Other patterns like object property assignments are not handled. ↓

fix Ensure your code uses var foo = function bar() {} to be transformed.

Install

npm install babel-plugin-transform-jscript

yarn add babel-plugin-transform-jscript

pnpm add babel-plugin-transform-jscript

Imports

default
wrong
```
const plugin = require('babel-plugin-transform-jscript')
```
correct
```
import plugin from 'babel-plugin-transform-jscript'
```
Babel 6 plugins are CommonJS, but import works with bundlers. For .babelrc, just use the string 'transform-jscript'.

Quickstart

Demonstrates how to enable the plugin via .babelrc and shows the transformation of a named function expression to an IIFE to fix JScript hoisting.

// .babelrc
{
  "plugins": ["transform-jscript"]
}
// input.js
var foo = function bar() {};
// output.js
var foo = (function() {
  var bar = function() {};
  return bar;
})();