[Python-checkins] [3.9] bpo-41370: Add note about ForwardRefs and PEP585 generic types in docs (GH-25183) (GH-25184)

[miss-islington]

https://github.com/python/cpython/commit/d56bcf915b8d5a6afe4555cb6813c8210824e751
commit: d56bcf915b8d5a6afe4555cb6813c8210824e751
branch: 3.9
author: Miss Islington (bot) <31488909+miss-islington at users.noreply.github.com>
committer: miss-islington <31488909+miss-islington at users.noreply.github.com>
date: 2021-04-04T08:36:21-07:00
summary:

[3.9] bpo-41370: Add note about ForwardRefs and PEP585 generic types in docs (GH-25183) (GH-25184)



(cherry picked from commit 2b5913b4ee5852a28ca1509478f5582beb3aff7b)


Co-authored-by: Ken Jin <28750310+Fidget-Spinner at users.noreply.github.com>

Automerge-Triggered-By: GH:gvanrossum

files:
M Doc/library/typing.rst

diff --git a/Doc/library/typing.rst b/Doc/library/typing.rst
index 688564f1d24f5..b136da00a070a 100644
--- a/Doc/library/typing.rst
+++ b/Doc/library/typing.rst
@@ -1710,10 +1710,15 @@ Introspection helpers
 .. class:: ForwardRef
 
    A class used for internal typing representation of string forward references.
-   For example, ``list["SomeClass"]`` is implicitly transformed into
-   ``list[ForwardRef("SomeClass")]``.  This class should not be instantiated by
+   For example, ``List["SomeClass"]`` is implicitly transformed into
+   ``List[ForwardRef("SomeClass")]``.  This class should not be instantiated by
    a user, but may be used by introspection tools.
 
+   .. note::
+      :pep:`585` generic types such as ``list["SomeClass"]`` will not be
+      implicitly transformed into ``list[ForwardRef("SomeClass")]`` and thus
+      will not automatically resolve to ``list[SomeClass]``.
+
    .. versionadded:: 3.7.4
 
 Constant