Based on suggestions by Guido van Rossum, Spencer Brown, and Alex Waygood.
Co-authored-by: Alex Waygood <Alex.Waygood@Gmail.com>
Co-authored-by: Guido van Rossum <gvanrossum@gmail.com>
Co-authored-by: Ken Jin <kenjin4096@gmail.com>
The goal here is to reduce potential confusion between
`assert_type(val, type)` and `assert isinstance(val, typ)`.
The former is meant to ask a type checker to confirm a fact, the latter
is meant to tell a type checker a fact. The behaviour of the latter more
closely resembles what I'd expect from the prior phrasing of
"assert [something] to the type checker".
There are several changes:
1. We now don't explicitly check for any base / sub types, because new name check covers it
2. I've also checked that `no_type_check` do not modify foreign functions. It was the same as with `type`s
3. I've also covered `except TypeError` in `no_type_check` with a simple test case, it was not covered at all
4. I also felt like adding `lambda` test is a good idea: because `lambda` is a bit of both in class bodies: a function and an assignment
<!-- issue-number: [bpo-46571](https://bugs.python.org/issue46571) -->
https://bugs.python.org/issue46571
<!-- /issue-number -->
The documentation explaining Python's data model does not adequately explain
the differences between ``__getitem__`` and ``__class_getitem__``, nor does it
explain when each is called. There is an attempt at explaining
``__class_getitem__`` in the documentation for ``GenericAlias`` objects, but
this does not give sufficient clarity into how the method works. Moreover, it
is the wrong place for that information to be found; the explanation of
``__class_getitem__`` should be in the documentation explaining the data model.
This PR has been split off from GH-29335.
``typing.Tuple`` has been deprecated since Python 3.9, so it makes no sense to mention it so prominently in the documentation for the ``typing`` module.
The list of PEPs at the top of the documentation for the ``typing`` module has
become too long to be readable. This PR proposes presenting this
information in a more structured and readable way by adding a new "relevant
PEPs" section to the ``typing`` docs.
Co-authored-by: Łukasz Langa <lukasz@langa.pl>
* Use "X | Y" instead of "Union" where it makes sense.
* Mention that "X | Y" is equivalent to "Union[X, Y]" in Union section.
* Remove "Optional[X]" as shorthand for "Union[X, None]" as the new
shorthand is now "X | None".
* Mention that "Optional[X]" can be written as "X | None" in section
about "Optional".
Co-authored-by: Ken Jin <28750310+Fidget-Spinner@users.noreply.github.com>