bpo-41370: Add note about ForwardRefs and PEP585 generic types in docs (#25183)

Fidget-Spinner · web-flow · commit 2b5913b4ee58 · 2021-04-04T08:14:44.000-07:00
diff --git a/Doc/library/typing.rst b/Doc/library/typing.rst
@@ -1948,10 +1948,15 @@ 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
