babel/packages/babel-plugin-transform-es2015-parameters
Justin Ridgewell c2ed9de7fb Flip default parameter template (#4515)
* Flip default parameter template

YMMV, I saved ~10b on a 2kb library. Not noticeable at the small scale, by why not do it anyway?

I've (unscientifically) found that flipping the default parameter conditional yields better gzip results. I think this is due to the slightly longer string it can now repeatedly match:

```js
// old
var param = arguments.length <= 0 || void 0 === arguments[0] ? null : arguments[0]
--------------------------------------------------------------^

// new
var param = arguments.length > 1 && void 0 !== arguments[1] ? arguments[1] : null
------------------------------------------------------------------------^
```

Though it's entirely likely gzip will also choose up to the index of the arguments if you many default parameters at different indexes.

* Update tests
2016-09-25 14:05:53 -07:00
..
2016-07-19 21:59:53 -04:00
2015-09-15 06:12:46 +01:00

babel-plugin-transform-es2015-parameters

Compile ES2015 default and rest parameters to ES5

Installation

$ npm install babel-plugin-transform-es2015-parameters

Usage

.babelrc

{
  "plugins": ["transform-es2015-parameters"]
}

Via CLI

$ babel --plugins transform-es2015-parameters script.js

Via Node API

require("babel-core").transform("code", {
  plugins: ["transform-es2015-parameters"]
});