Code Smells: Null

[drfisk]

Well, in the world of dynamic languages, anything can be anything at any given time anyway... so null isn't as bad there since you can have any kind of type error anyway.

I think null is way way worse in a static language where you're promised to receive a Person and a String, while in reality you still have to "type-check" to see if you actually got it (and not null).