[Python-checkins] cpython (3.5): Issue #12067: Recommend that hash and equality be consistent

[martin.panter]

https://hg.python.org/cpython/rev/8c9a86aa222e
changeset:   106329:8c9a86aa222e
branch:      3.5
parent:      106320:91b949dc1984
user:        Martin Panter <vadmium+py at gmail.com>
date:        Sun Jan 29 10:00:23 2017 +0000
summary:
  Issue #12067: Recommend that hash and equality be consistent

files:
  Doc/reference/expressions.rst |  4 ++++
  1 files changed, 4 insertions(+), 0 deletions(-)


diff --git a/Doc/reference/expressions.rst b/Doc/reference/expressions.rst
--- a/Doc/reference/expressions.rst
+++ b/Doc/reference/expressions.rst
@@ -1255,6 +1255,10 @@
   sequences, but not to sets or mappings). See also the
   :func:`~functools.total_ordering` decorator.
 
+* The :func:`hash` result should be consistent with equality.
+  Objects that are equal should either have the same hash value,
+  or be marked as unhashable.
+
 Python does not enforce these consistency rules. In fact, the not-a-number
 values are an example for not following these rules.
 

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