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Yeah, I guess few developers have needed to use _dump_registry(), and also it's easy enough to just access e.g. Iterator._abc_registry yourself. The reason Iterator._abc_registry is empty is that no class directly registered with it -- they are all registered with e.g. Sequence. The cache includes classes registered with subclasses, but the registry itself does not. I guess a PR to fix the registry output would make sense (first file a bug on bugs.python.org for it). On Sat, Dec 30, 2017 at 11:19 PM, Yahya Abou 'Imran via Python-ideas < python-ideas@python.org> wrote:
In python 2.7, ABCs's caches and registries are sets. But in python 3.6 they are WeakSet. In consequence, the output of _dump_registry() is almost useless:
from collections import abc abc.Iterator._dump_registry() Class: collections.abc.Iterator Inv.counter: 40 _abc_cache: <_weakrefset.WeakSet object at 0x7f4b58fe2668> _abc_negative_cache: <_weakrefset.WeakSet object at 0x7f4b53283780> _abc_negative_cache_version: 40 _abc_registry: <_weakrefset.WeakSet object at 0x7f4b58fe2630>
We could convert them into a regular set before printing:
if isinstance(value, WeakSet): value = set(value)
The result:
abc.Iterator._dump_registry() Class: collections.abc.Iterator Inv.counter: 40 _abc_cache: {<class 'dict_valueiterator'>, <class 'bytearray_iterator'>, <class 'tuple_iterator'>, <class 'dict_itemiterator'>, <class 'dict_keyiterator'>, <class 'str_iterator'>, <class 'zip'>, <class 'set_iterator'>, <class 'list_reverseiterator'>, <class 'range_iterator'>, <class 'longrange_iterator'>, <class 'list_iterator'>, <class 'bytes_iterator'>} _abc_negative_cache: set() _abc_negative_cache_version: 40 _abc_registry: set()
NB: It seems pretty weird to me that registry is empty... All the iterators in the cache should've been in the registry instead, should'nt they? _______________________________________________ Python-ideas mailing list Python-ideas@python.org https://mail.python.org/mailman/listinfo/python-ideas Code of Conduct: http://python.org/psf/codeofconduct/
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