frequency-mangle

A property/string mangle tools for javascript.

###Install
npm install --save-dev frequency-mangle

###How it works?
frequency-mangle analyze the code by using esprima.
frequency-mangle will get all the stats of properties or strings.

This is very useful when using Babel in development.

Babel will transform React jsx tags into React.createElement. If there are lots of tags, there will be hundreds of createElement in the bundle even if it is minfied.

Such problems also occurs when Babel transform ES6 Classes. Each ES6 Class will be transform according to template of Babel which contains a lot of strings like "this hasn't been initialised - super() hasn't been called", "Super expression must either be null or a function, not ", "__esModule" and etc.

Some properties or words are of high frequency in certain Apps. For example, we will write this.setState, this.state, this.props many times. React.ProtoTypes will also be used frequently. ES6 class methods will be transformed into properties of Object by Babel, so some string can also be seen frequently in bundles, such as componentDidMount, componentWillUnmount and etc.

frequency-mangle gather all the stats of such information and provide a chance to use variables to replace such words.

Simply it can be:
``
(function(){
var a = "setState", b = "default", ...
thisa..
export[b] ...
})();
`

Caution: frequency-mangle may take a long time to mangle. Make sure you won't use it frequently on large bundles.
Note: frequency-mangle will create IIFE to wrap origin code. So do not use it on ES6 with import` or other codes which may cause side-effect.