Webpack loader for add private props to javascript

Add privates to javascript in file level. Props when start with _ will be replaced to symbols. Its just experiment =).

Actually next in next ECMA specifications, private props will be like this#prop = 11. So, this webpack loader is temporary solution.

Example:

class EventEmitter {

  constructor() {
    this._handlers = []
    this._initHandlers()
  }

  _initHandlers() {

  }

}

compile to:

var $$handlers$$ = Symbol('handlers');
var $$initHandlers$$ = Symbol('initHandlers');

class EventEmitter {

  constructor() {
    this[$$handlers$$] = []
    this[$$initHandlers$$]()
  }

  [$$initHandlers$$]() {
    
  }

}

TODO:

• Add obj#prop in ECMA specifications
• Add class level scope, no file scope
• Add obj#prop support to Babel
• Fix var _name, now its compile to var [$$name$$], this is syntax error.
• Fix function _name(){}, now its compile to function [$$name$$]{}, this is syntax error.
• Fix `str${this._prop}ing` must be `str${this[$$prop$$]}ing`