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

2010/8/24 Hrvoje Niksic <hrvoje.niksic@avl.com>:

The __length_hint__ lookup expects either no exception or AttributeError, and will propagate others.  I'm not sure if this is a bug.  On the one hand, throwing anything except AttributeError from __getattr__ is bad style (which is why we fixed the bug by deriving our business exception from AttributeError), but the __length_hint__ check is supposed to be an internal optimization completely invisible to the caller of list().

__length_hint__ is internal and undocumented, so it can do whatever it wants. -- Regards, Benjamin