Document typing.ForwardRef (GH-14216)

diff --git a/Doc/library/typing.rst b/Doc/library/typing.rst
index 1a766c29a57a53176dc07d1d7b5b3c95bca9dd55..d2dd03d50fc6e74dc734d5f05c96d225f54fb8c4 100644 (file)
--- a/Doc/library/typing.rst
+++ b/Doc/library/typing.rst
@@ -1001,6 +1001,13 @@ The module defines the following classes, functions and decorators:
 
    .. versionadded:: 3.8
 
+.. 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
+   a user, but may be used by introspection tools.
+
 .. function:: NewType(typ)
 
    A helper function to indicate a distinct types to a typechecker,