[PRL] Pac-Man's Ghost Behavior Analyzed and Fixed

[Doug Orleans]

This is from a couple years ago, but I just ran across it:

http://donhodges.com/pacman_pinky_explanation.htm

It's a dissection of a bug in the Z80 programming for the "Pinky"
ghost's behavior in the original Pac-Man.  Note that there's a slight
inaccuracy in his description of the bug behavior; see if you can spot
it!

I'm wondering if there's a moral in here for modern programmers (or
programming language designers).  Like, what kind of type system would
detect the type error in this code, assuming the programmer defined
the types accurately?

--Doug