On 2011-10-01, at 20:33 , Antoine Pitrou wrote:
Ah, thanks for the pointer. I think we should add a custom IOBase.__contains__ raising a TypeError, then. The current semantics don't match what most people would expect from a "file containment" predicate.
I think it'd also be nice to add them to some "chopping block" list for Python 4: I've yet to see these fallbacks result in anything but pain and suffering, and they can be genuinely destructive and cause hard-to- track bug, especially with modern Python code's tendency to use (non-restartable) iterators and generators (send a generator to a function which seems to take them, it performs some sort of containment check before processing, the containment consumes the generator and proceeds to not do any processing…)