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# babel-plugin-transform-class-properties
> This plugin transforms es2015 static class properties as well as properties declared with the es2016 property initializer syntax.
## Example
Below is a class with four class properties which will be transformed.
```js
class Bork {
//Property initializer syntax
instanceProperty = "bork";
boundFunction = () => {
return this.instanceProperty;
}
//Static class properties
static staticProperty = "babelIsCool";
static staticFunction = function() {
return Bork.staticProperty;
}
}
let myBork = new Bork;
//Property initializers are not on the prototype.
console.log(myBork.prototype.boundFunction); // > undefined
//Bound functions are bound to the class instance.
console.log(myBork.boundFunction.call(undefined)); // > "bork"
//Static function exists on the class.
console.log(Bork.staticFunction()); // > "babelIsCool"
```
## Installation
```sh
npm install --save-dev babel-plugin-transform-class-properties
```
## Usage
### Via `.babelrc` (Recommended)
**.babelrc**
```json
// without options
{
"plugins": ["transform-class-properties"]
}
// with options
{
"plugins": [
["transform-class-properties", { "spec": true }]
]
}
```
### Via CLI
```sh
babel --plugins transform-class-properties script.js
```
### Via Node API
```javascript
require("babel-core").transform("code", {
plugins: ["transform-class-properties"]
});
```
## Options
### `spec`
`boolean`, defaults to `false`.
Class properties are compiled to use `Object.defineProperty`. Static fields are now defined even if they are not initialized.
## References
* [Proposal: ES Class Fields & Static Properties](https://github.com/jeffmo/es-class-static-properties-and-fields)