> Or you can assume it's implemented sanely

excuse me, have you spent any time in tech? people fucking love to do clever shit that gets people in trouble. using NULL as a not-pointer value signalling absence (without safeguards) is probably the most notorious -- but at least useful, but if you want to get brain meltingly annoying and pervasive, we dont have to stray too far from the idea of operator overloading; c++'s << operator can just go to hell.