Basic Scope Closure of Javascript

base_javascript.js

// define root module
var rm = rm || {};

// define a module under root module
rm.person = function (win, doc) {
    // current module
    var module = {
        // module var
        coding: "utf-8",
        // module function another name is static function
        print: function (name, age) {
            console.log('name: ' + name + ' age: '+ age);
        },
        // module class
        Person: function (name, age) {
            if (!(this instanceof module.Person)) {
                // create a new instance for apply arguments
                // note new instance is a subclass of Person but nothing customized
                return module.Person.apply(new module._Person(), arguments);
            }

            // call inhert function from super class
            this.print();

            // instance var
            this.name = name;
            this.age = age;

            // instance function
            this.print = function () {
                console.log("I'm in a instance begin.");

                // call class function
                module.Person.prototype.print.apply(this, arguments);

                console.log("I'm in a instance end.");
            };

            // call instance function
            this.print();

            // return this pointer to comparability not with new keyword initial
            return this;
        },
        _Person: function () {}
    };
    // module class var and function
    module.Person.prototype = {
        name: 'class_name',
        age: 'class_age',
        print: function () {
            module.print(this.name, this.age);
        }
    };
    // define subclass of Person
    module._Person.prototype = module.Person.prototype;
    return module;
}(window, document);