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Author rhettinger
Recipients Nan Wu, brett.cannon, gvanrossum, rhettinger
Date 2015-11-15.21:11:42
SpamBayes Score -1.0
Marked as misclassified Yes
Message-id <>
-0 on this one.  This is slightly more useful than the other "one-trick-ponies" like Container, Hashable, and Iterable.  Those each provide some "recognition" capabilities using isinstance() but don't provide any useful "mixin" capabilities.  

In practice, I'm not seeing the "recognition" capabilities being used (i.e. no one is using "if isinstance(obj, Container)" in real code).  So adding another one-trick pony that won't get used is a bit of a waste.  

Also, this would add more clutter to the collections ABCs, obscuring the ones that actually have added value (i.e. MutableMapping has been a great success).  The module has become a dumping ground for ABCs that that don't really have anything to do with collections and aren't useful for day-to-day development (Awaitable, Coroutine, AsyncIterable, AsyncIterator, etc).

One idea is to have a separate module of generic recognition abcs that would be used in much the same way as the old types module.  Otherwise, the module will continue unabated growth away from its original purpose as a small group of powerful mixin classes (Sequence, MutableSequence, Set, MutableSet, Mapping, MutableMapping, and the dict views).
Date User Action Args
2015-11-15 21:11:42rhettingersetrecipients: + rhettinger, gvanrossum, brett.cannon, Nan Wu
2015-11-15 21:11:42rhettingersetmessageid: <>
2015-11-15 21:11:42rhettingerlinkissue25609 messages
2015-11-15 21:11:42rhettingercreate