Re: [Python-Dev] 'hasattr' is broken by design

2010/8/23 Guido van Rossum <guido@python.org>:

The main problem I can see with letting exceptions other than AttributeError bubble through (besides perverted dependencies on the current semantics) is that there are some situations where it is pretty arbitrary whether TypeError or AttributeError is raised. I can't recall the details, and possibly this was more of a problem with classic classes, but I do think it warrants some research.

I believe this was with regards to actual operations, though, not fetching the attribute. For example, float(a) would raise an AttributeError for a classic instance and a TypeError for a new-style instance. However both would raise AttributeError on a.__float__. -- Regards, Benjamin