text: /*
  * @Author: Hans Jürgen Gessinger
  * @Date:   2019-04-05 18:50:25
  * @Last Modified by:   Hans+JÃ¼rgen Gessinger
  * @Last Modified time: 2019-09-17 12:41:58
  */
  'use strict';
  let assert = require('assert')
  const calculator = {};
  
  calculator.add = function(left, right)
  {
  	assert(typeof left === 'number' && typeof right === 'number', 'Invalid numbers')
  	return left + right;
  }
  
  module.exports = calculator;