jsPattern.OOPsubClass.js - an example of implementing subclass feature.

jsPattern.OOPsubClass.js

(function () {
    var initializing = false,
        superPattern =
            /xyz/.test(function () {    //check if supoort fucntion serialization.
            xyz;
        }) ? /\b_super\b/ : /.*/;

    Object.subClass = function (properties) {
        var _super = this.prototype;
        initializing = true;
        var proto = new this();
        initializing = false;
        for (var name in properties) {
            proto[name] = typeof properties[name] == "function" && typeof _super[name] == "function" && superPattern.test(properties[name]) ? (function (name, fn) {
                return function () {
                    var tmp = this._super;
                    this._super = _super[name];
                    var ret = fn.apply(this, arguments);
                    this._super = tmp;
                    return ret;
                };
            })(name, properties[name]) : properties[name];
        }

        function Class() {
            // All construction is actually done in the init method
            if (!initializing && this.init) this.init.apply(this, arguments);
        }
        Class.prototype = proto;
        Class.constructor = Class;
        Class.subClass = arguments.callee;
        return Class;
    };
})();