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# babel-plugin-transform-object-rest-spread
> This plugin allows Babel to transform rest properties for object destructuring assignment and spread properties for object literals.
## Example
### Rest Properties
```js
let { x, y, ...z } = { x: 1, y: 2, a: 3, b: 4 };
console.log(x); // 1
console.log(y); // 2
console.log(z); // { a: 3, b: 4 }
```
### Spread Properties
```js
let n = { x, y, ...z };
console.log(n); // { x: 1, y: 2, a: 3, b: 4 }
```
## Installation
```sh
npm install --save-dev babel-plugin-transform-object-rest-spread
```
## Usage
### Via `.babelrc` (Recommended)
**.babelrc**
```json
{
"plugins": ["transform-object-rest-spread"]
}
```
### Via CLI
```sh
babel --plugins transform-object-rest-spread script.js
```
### Via Node API
```javascript
require("babel-core").transform("code", {
plugins: ["transform-object-rest-spread"]
});
```
## Options
### `useBuiltIns`
`boolean`, defaults to `false`.
By default, this plugin uses Babel's `extends` helper which polyfills `Object.assign`. Enabling this option will use `Object.assign` directly.
**.babelrc**
```json
{
"plugins": [
["transform-object-rest-spread", { "useBuiltIns": true }]
]
}
```
**In**
```js
z = { x, ...y };
```
**Out**
```js
z = Object.assign({ x }, y);
```
## References
* [Proposal: Object Rest/Spread Properties for ECMAScript](https://github.com/sebmarkbage/ecmascript-rest-spread)
* [Spec](http://sebmarkbage.github.io/ecmascript-rest-spread)
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