Bind private functions to this

bind-functions-to-this.js

function myFunc1() {
  console.log(this.myProp)
}
function myFunc2() {}
const _p = {}

/**
 * bind an array of functions to this
 * WARNING: only works with named functions
 * @param  {object}         instance         pass the instance this
 * @param  {fnToBind}       fnToBind         array with all the function to bind to this
 * @param  {privatePrefix}  privatePrefix    prefix where all the private bound functions are
 */
const bindFunctions = (instance, fnToBind, privatePrefix) => {
  fnToBind.forEach(fn => {
    privatePrefix[fn.name] = fn.bind(instance)
  })
}

class MyClass {
  constructor(myProp) {
    this.myProp = myProp
    bindFunctions(this, [myFunc1, myFunc2], _p)
  }

  myPublicMethod() {
    _p.myFunc1()
  }
}

Better if Symbol is supported: https://medium.com/@davidrhyswhite/private-members-in-es6-db1ccd6128a5
https://gist.github.com/davidrhyswhite/84eb4f0295c402c5546a