Isn't it just (untested, probably full of errors): function super(obj, method) { for (var p = obj.prototype; p; p = p.prototype) if (p[

Isn't it just (untested, probably full of errors): function super(obj, method) { for (var p = obj.prototype; p; p = p.prototype) if (p[method]) return p[method]; throw method+" not found"; } then use: subclass.prototype.overridden = function(x,y) { super(this, 'some_overriden_method').call(this, x, y); // ... } If so, that means it's just sugar. If not, what does it do differently?