ex4.js

var Module = Stapes.subclass({
    sayName : function() {
        console.log('i say my name!');
    }
});

var BetterModule = Module.subclass({
    // Note that this method name is the same as the one in Module
    sayName : function() {
        BetterModule.parent.sayName.apply(this, arguments);
        console.log('i say my name better');
    }
});

var module = new BetterModule();
module.sayName(); // 'i say my name! i say my name better!'