Equality isn't transitive in PHP :/. Of course, IMO, the real coding horror here is that in an error circumstance no exception is raised.

This. There are dozens of situations where, given instructions that simply don't make sense, PHP arbitrarily picks some half-baked behavior instead of giving an error. So much so that I think the original poster is out of line for even considering tax planning in a language that wants to guess what you might have wanted to happen!

+1

While I understand (and agree with) the change to try and standardize PHP behavior, I think that in this case the parent comment is the crux of the issue. Seems like returning NULL violates the principle of least surprise to me.