Changeset 391 for python/trunk/Doc/library/constants.rst

Timestamp:

Mar 19, 2014, 11:31:01 PM (11 years ago)

Author:

dmik

Message:

python: Merge vendor 2.7.6 to trunk.

Location:

python/trunk

Files:

• . (modified) (1 prop)
• Doc/library/constants.rst (modified) (2 diffs)

python/trunk/Doc/library/constants.rst

@@ +1 @@
+.. _built-in-consts:
+
 Built-in Constants
 ==================
 
 A small number of constants live in the built-in namespace.  They are:
-
 
 .. data:: False
@@ -40 +41 @@
    Special value used in conjunction with extended slicing syntax.
 
-   .. XXX Someone who understands extended slicing should fill in here.
-
 
 .. data:: __debug__
 
    This constant is true if Python was not started with an :option:`-O` option.
-   Assignments to :const:`__debug__` are illegal and raise a :exc:`SyntaxError`.
    See also the :keyword:`assert` statement.
+
+
+.. note::
+
+   The names :data:`None` and :data:`__debug__` cannot be reassigned
+   (assignments to them, even as an attribute name, raise :exc:`SyntaxError`),
+   so they can be considered "true" constants.
+
+   .. versionchanged:: 2.7
+      Assignments to ``__debug__`` as an attribute became illegal.