resig-netflix-inheritance.js

    /* Simple JavaScript Inheritance with NFE's
     * MIT Licensed.
     */
    // Inspired by base2 and Prototype and John Resig's class system
    (function(){
        var initializing = false;
    
        // The base Class implementation (does nothing)
        this.Class = function(){};
    
        // Create a new Class that inherits from this class
        Class.extend = function extend(prop) {
            var _super = this.prototype;
    
            // Instantiate a base class (but only create the instance,
            // don't run the init constructor)
            initializing = true;
            var prototype = new this();
            initializing = false;
    
            // Copy the properties over onto the new prototype
            for (var name in prop) {
                // if we're overwriting an existing function
                // set the base property
                var value = prop[name];
                if (typeof prop[name] == "function" && typeof _super[name] == "function"){
                    value.base = _super[name];
                }
                prototype[name] = value;
            }
    
            // The dummy class constructor
            function Class() {
                // All construction is actually done in the init method
                if ( !initializing && this.init )
                    this.init.apply(this, arguments);
            }
    
            // Populate our constructed prototype object
            Class.prototype = prototype;
    
            // Enforce the constructor to be what we expect
            Class.prototype.constructor = Class;
    
            // And make this class extendable
            Class.extend = arguments.callee;
    
            return Class;
        };
    })();
    
    /*
    //Example from the article:
    var Human = Class.extend({
        init: function (height, weight){
            this.height = height;
            this.weight = weight;
        }
    });
    var Mutant = Human.extend({
        init: function init(height, weight, abilities){
            init.base.call(this, height, weight);
            this.abilities = abilities;
        }
    });
    
    var theWolverine = new Mutant('5ft 3in', 300, [
        'adamantium skeleton',
        'heals quickly',
        'claws'
    ]);    
    */