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node_modules/babel-plugin-transform-undefined-to-void/README.md

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+# 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**
+
+```javascript
+foo === undefined;
+```
+
+**Out**
+
+```javascript
+foo === void 0;
+```
+
+## Installation
+
+```sh
+npm install babel-plugin-transform-undefined-to-void
+```
+
+## Usage
+
+### Via `.babelrc` (Recommended)
+
+**.babelrc**
+
+```json
+{
+  "plugins": ["transform-undefined-to-void"]
+}
+```
+
+### Via CLI
+
+```sh
+babel --plugins transform-undefined-to-void script.js
+```
+
+### Via Node API
+
+```javascript
+require("@babel/core").transform("code", {
+  plugins: ["transform-undefined-to-void"]
+});
+```