Simple example of JavaScript namespaces, classes and inheritance

Question

I've been asked to port some of our PHP code across to JavaScript, so that more of our logic runs client-side. What'd I'd like is a simple example that shows:

• a namespace ("Package") containing two classes ("Master" and "Slave")
• the "Master" class has a property "p", a function "m" and a constructor that takes a single argument to set the initial value of "p"
• the "Slave" class inherits both "p", the constructor and "m" from the "Master" class

I don't mind using some sort of existing framework, but it must be lightweight -- ideally no more than 200 LOC (un-minified).

Here's my attempt, FWIW:

var Package = {};

Package.Master = function(pValue) {
    this.p = pValue;
    this.m = function() {
        alert("mmmmm");
    }
}

Package.Slave = function(pValue) {
    // this will inherit from Package.Master
}

// one of the many online examples:
// http://kevlindev.com/tutorials/javascript/inheritance/index.htm
KevLinDev.extend = function(subClass, baseClass) {
   function inheritance() {}
   inheritance.prototype = baseClass.prototype;

   subClass.prototype = new inheritance();
   subClass.prototype.constructor = subClass;
   subClass.baseConstructor = baseClass;
   subClass.superClass = baseClass.prototype;
}

KevLinDev.extend(Package.Slave, Package.Master);

Answer 1

I'm quite a fan of John Resig's Simple Javascript Inheritance.

E.g.:

var Package = {};
Package.Master = Class.extend({
    init: function(pValue) {
        this.p = pValue;
    },
    m: function() {
        alert("mmmmm");
    }
});

Package.Slave = Package.Master.extend({
    init: function(pValue) {
        this._super(pValue);
    }
});

var slave = new Package.Slave(10);
slave.m();