Not really, javascript provides very little core behavioral hooks for instance: no creation hook (new/__new__, yeah you can return your own instance in the constructor but it'll still build an instance regardless), no general attribute-access until proxies (method_missing/__getattr__), no operators override (save through toString/valueOf hacks and that won't work for []), no conversion hooks (again, aside from toString/valueOf), etc...

Compare and contrast: http://docs.python.org/3/reference/datamodel.html#special-me...

Ruby provides roughly the same level of hooking (not sure it allows overriding instance or subclass checks, but it allow overriding things Python does not as well), but JS most definitely does not.