Privates in JavaScript Classes, medium, using closures, es6

private-using-closure-es6.js

// private variables
let _balance = 0
let _logs = []

export default class Bank {
  constructor() {
    // public variables
    this.name = 'B7'
  }
  
  // public methods
  getBalance() {
    return _balance
  }

  addToBalance(count) {
    _addBalance(count)
    return this.getBalance()
  }
}

// private methods
const _addBalance = (count) => {
  _logBankChange('add', count)
  _balance += count
}
const _logBankChange = (type, count) => {
  _logs.push({ type, count })
}