[Python-checkins] bpo-32892: Update the documentation for handling constants in AST. (GH-18514)

[Serhiy Storchaka]

https://github.com/python/cpython/commit/85a2eef473a2c9ed3ab9c6ee339891fe99adbbc9
commit: 85a2eef473a2c9ed3ab9c6ee339891fe99adbbc9
branch: master
author: Serhiy Storchaka <storchaka at gmail.com>
committer: GitHub <noreply at github.com>
date: 2020-02-17T11:03:00+02:00
summary:

bpo-32892: Update the documentation for handling constants in AST. (GH-18514)

files:
M Doc/library/ast.rst
M Doc/whatsnew/3.8.rst

diff --git a/Doc/library/ast.rst b/Doc/library/ast.rst
index 2cee8738e5834..bfd571deb4fd1 100644
--- a/Doc/library/ast.rst
+++ b/Doc/library/ast.rst
@@ -101,12 +101,16 @@ Node classes
       node = ast.UnaryOp(ast.USub(), ast.Constant(5, lineno=0, col_offset=0),
                          lineno=0, col_offset=0)
 
+.. versionchanged:: 3.8
+
+   Class :class:`ast.Constant` is now used for all constants.
+
 .. deprecated:: 3.8
 
-   Class :class:`ast.Constant` is now used for all constants. Old classes
-   :class:`ast.Num`, :class:`ast.Str`, :class:`ast.Bytes`,
+   Old classes :class:`ast.Num`, :class:`ast.Str`, :class:`ast.Bytes`,
    :class:`ast.NameConstant` and :class:`ast.Ellipsis` are still available,
-   but they will be removed in future Python releases.
+   but they will be removed in future Python releases.  In the meanwhile,
+   instantiating them will return an instance of a different class.
 
 
 .. _abstract-grammar:
diff --git a/Doc/whatsnew/3.8.rst b/Doc/whatsnew/3.8.rst
index cb4c518662d6b..09047c460df01 100644
--- a/Doc/whatsnew/3.8.rst
+++ b/Doc/whatsnew/3.8.rst
@@ -1940,6 +1940,12 @@ Changes in the Python API
   :exc:`dbm.gnu.error` or :exc:`dbm.ndbm.error`) instead of :exc:`KeyError`.
   (Contributed by Xiang Zhang in :issue:`33106`.)
 
+* Simplified AST for literals.  All constants will be represented as
+  :class:`ast.Constant` instances.  Instantiating old classes ``Num``,
+  ``Str``, ``Bytes``, ``NameConstant`` and ``Ellipsis`` will return
+  an instance of ``Constant``.
+  (Contributed by Serhiy Storchaka in :issue:`32892`.)
+
 * :func:`~os.path.expanduser` on Windows now prefers the :envvar:`USERPROFILE`
   environment variable and does not use :envvar:`HOME`, which is not normally
   set for regular user accounts.