JSFiddle - React, Tailwind, and code Playground

JavaScript

var MYNamespace = MYNamespace|| {};

 MYNamespace.MyFirstClass = function (val) {
        this.value = val;
        this.getValue = function(){
                          return this.value;
                       };
        this.Save= function(var2) {
        	return 'Save ' + var2;
        }
    }

var myFirstInstance = new MYNamespace.MyFirstClass(46);
alert(myFirstInstance.Save('kk'));