Currently, you cannot use isinstance checks on threading locks, because they're created by a factory function instead of being actual classes. Now that we've got __subclasshook__ and __instancecheck__, is there still a reason other than "history" that we can't use isinstance here ? There could exist a thin wrapper class along the lines of: class Lock: def __new__(): return __allocate_lock() # Call factory function @classmethod def __subclasshook__(cls, inst): # code... As far as I can think, no code would be broken by this - even current introspection which we're trying to replace would work just fine. My C experience is rather limited, so i dont know if it's hard to write the subclass /isinstance checks. While probably not that important, would people consider this to be a good idea ? (I found this bug report: https://bugs.python.org/issue3352 which has a post of Nick Coghlan from 2008-07-14 22:25 where this is mentioned - but in respect to multiprocessing. However, that thread is rather old and dead. I could not find any other references to this.)
participants (2)
-
Guido van Rossum -
Jacco van Dorp