Ian Bicking: the old part of his blog

Comment

I guess I should say that I think things like this should really be used when you are writing something error-prone -- something that is complex and easily misused. It's not even something I'd consider a "rule". I often use default arguments, and changing APIs is a frequent reason. This is more a suggestion that we be a bit reluctant in using default arguments, not that we go so far as to avoid them.
Comment on A Python Poka-Yoke
by Ian Bicking