
On 24/05/17 14:31, Ivan Levkivskyi wrote:
Hi all,
After collecting suggestions in the previous discussion on python-dev https://mail.python.org/pipermail/python-dev/2017-March/thread.html#147629 and playing with implementation, here is an updated version of PEP 544.
-- Ivan
I really like this PEP in general. I think this brings the type system for type-hints closer to Python semantics. But there are a few points I disagree with. I don't think Protocol types should be tied to ABCs. It just makes things more complex with no obvious benefit. I also think all references to 'isinstance' and 'issubclass' should be removed. Type-hints should not have runtime semantics, beyond those that they have as classes. In fact, there is no need for protocol types to be classes at all. Cheers, Mark.