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babel-plugin-transform-undefined-to-void v6.9.4

Replace references to `undefined` with `void 0`

babel-plugin-transform-undefined-to-void

Some JavaScript implementations allow undefined to be overwritten, this may lead to peculiar bugs that are extremely hard to track down.

This plugin transforms undefined into void 0 which returns undefined regardless of if it's been reassigned.

Example

In

foo === undefined;

Out

foo === void 0;

Installation

npm install babel-plugin-transform-undefined-to-void --save-dev

Usage

Via .babelrc (Recommended)

.babelrc

{
  "plugins": ["transform-undefined-to-void"]
}

Via CLI

babel --plugins transform-undefined-to-void script.js

Via Node API

require("@babel/core").transform("code", {
  plugins: ["transform-undefined-to-void"]
});
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