On Wed, Feb 13, 2013 at 9:09 PM, Xavier Morel <python-...@masklinn.net> wrote: > On 2013-02-13, at 19:48 , Maciej Fijalkowski wrote: > >> Hi >> >> I've tried (and failed) to find what GC details (especially finalizer >> semantics) are CPython only and which ones are not. The best I could >> find was the documentation of __del__ here: >> http://docs.python.org/2/reference/datamodel.html >> >> Things were pypy differs: >> >> * finalizers in pypy will be called only once, even if the object is >> resurrected. I'm not sure if this is detail or we're just plain >> incompatible. >> >> * pypy breaks cycles and runs finalizers in random order (but >> topologically correct), hence gc.garbage is always empty. I *think* >> this part is really just an implementation detail >> >> * we're discussing right now about running multiple finalizers. We >> want to run them in order, but if there is a link a -> b and a becomes >> unreachable, we want to reserve the right to call finalizer a then >> finalizer b, even if a.__del__ resurrects a. What do you think? >> >> Overall, the __del__ is baaad. >> >> Cheers, >> fijal > > There may be one more, although I'm not sure whether it's a GC artifact > or something completely unspecified: if a context manager is part of a > suspended stack (because it's in a generator) when the program > terminates, cpython will run __exit__ but pypy will not > > -- > # -*- encoding: utf-8 -*- > class C(object): > def __enter__(self): > print ("entering") > def __exit__(self, *args): > print ("exiting") > > def gen(): > with C(): > yield > > r = gen() > next(r) > -- > $ python2 test.py > entering > exiting > $ python3 test.py > entering > exiting > $ pypy test.py > entering > $ > -- > > _______________________________________________ > Python-Dev mailing list > Python-Dev@python.org > http://mail.python.org/mailman/listinfo/python-dev > Unsubscribe: > http://mail.python.org/mailman/options/python-dev/fijall%40gmail.com
I think it's well documented you should not rely on stuff like that being run at the exit of the interpreter. I think we'll try harder to run finalizers at the end of the interpreter (right now we only flush files). File the issue. _______________________________________________ Python-Dev mailing list Python-Dev@python.org http://mail.python.org/mailman/listinfo/python-dev Unsubscribe: http://mail.python.org/mailman/options/python-dev/archive%40mail-archive.com
