* Check created date exists & matches format, and fix non-conforming
* Automatically fix mixed EoLs on checkin and in one PEP
* Add rst-directive-colons check, fix issue it found and refine regex
* Change name of `MATCH_CLASS` to `MATCH_POSITIONAL`.
* Drop `__attributes__` and use `__match_args__` instead.
* For `MATCH_DEFAULT`, `__match_args__` acts a map from positions to names.
* For `MATCH_POSITIONAL`, `__match_args__` acts a map from names to positions.
* Change semantics of `MATCH_DEFAULT` when match class patterns to those of PEP 634.
* Update translations.
* Further expand examples
This is the more-or-less final version now. I'll do one last read-through to confirm everything's consistent, then post in typing-sig to confirm it's ready for the Steering Committee.
Semantic changes:
* Remove support for type variable tuples in `Union`. Apparently the implementation would be tricky in Pyre because of special-casing around `Union`. That could be evidence that it would be tricky in Mypy and pytype. Since we don't have a specific use-case in mind, I think this is fine.
* Support concatenation in `Callable`. Pradeep pointed ou that `ParamSpec` doesn't cover all potential use-cases because it doesn't support concatenating suffixes (in turn because `ParamSpec`s can contain keyword arguments, and concatenation is positional).
Readability changes:
* Remove the section on a full `Array` example. We've moved the important thing here - an explicit confirmation that `Array` can be generic in both datatype and shape - to the beginning of the PEP to make it more obvious. We've removed the `Ndim` thing after someone pointed out that e.g. `Ndim[Literal[2]]` would be incompatible with `Shape[Any, Any]`; I just don't think it's going to work. All that's left is the aliases, which we've moved into the Aliases section itself.
Other changes:
* Fill out Backwards Compatibility section.
* Reference initial CPython implementation.
Guilhem Saurel
Jelle Zijlstra
CAM Gerlach
Brett Cannon
Dong-hee Na
Irit Katriel
Tzu-ping Chung
Matthew Rahtz
Christian Heimes
Mark Shannon
Batuhan Taskaya
Sumana Harihareswara
Victor Stinner
Thomas Kluyver
Inada Naoki
Dustin Ingram
Dave Brondsema
Pablo Galindo
Sean Lockwood
Jacob Walls
David Foster
Naren Santhanam