[Python-checkins] peps: PEP 495: Added a preamble to a first=None variant.

[alexander.belopolsky]

https://hg.python.org/peps/rev/b5a16f2bf11e
changeset:   5987:b5a16f2bf11e
user:        Alexander Belopolsky <alexander.belopolsky at gmail.com>
date:        Mon Aug 24 17:29:10 2015 -0400
summary:
  PEP 495: Added a preamble to a first=None variant.

files:
  pep-0495.txt |  6 ++++++
  1 files changed, 6 insertions(+), 0 deletions(-)


diff --git a/pep-0495.txt b/pep-0495.txt
--- a/pep-0495.txt
+++ b/pep-0495.txt
@@ -509,6 +509,12 @@
 Backward Compatibility
 ......................
 
+It has been suggested that backward compatibility can be improved if
+the default value of the ``first`` flag was ``None`` which would
+signal that pre-PEP behavior is requested.  Based on the analysis
+below, we believe that the proposed changes with the ``first=True``
+default are sufficiently backward compatible.
+
 This PEP provides only three ways for a program to discover that two
 otherwise identical datetime instances have different values of
 ``first``: (1) an explicit check of the ``first`` attribute; (2) if

-- 
Repository URL: https://hg.python.org/peps