[Python-Dev] Weak Dictionary Iteration Behavior in Python 3

[Georg Brandl]

Nick Coghlan schrieb:
> Armin Ronacher wrote:
>> Speaking of atom keys() / values() / items() operations: I guess we will
>> see more of those problems in threaded situations when people start to
>> convert code over to Python.  I've seen quite a few situations where code
>> relays on keys() holding the interpreter lock.
> 
> list(iter) doesn't re-enter the eval loop if the iterator is written in
> C and hence won't let go of the GIL. As I believe the dict views in 3.0
> are all C classes, I'd like to see a failing test case along these lines
> that doesn't involve a dict subclass and code written in Python.

WeakKeyDictionary.keys() iterates over its .data dictionary's keys() instead
of list(data.keys()). Therefore, the user of WeakKeyDictionary has no chance
to do list(keys()) without running Python code.

Georg


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