2011/4/27 Łukasz Langa <luk...@langa.pl>: > # Or even: >>>> inf+1 == inf-1 > True > > For the infinity part, I believe this is related to the funky IEEE 754 > standard. I found > some discussion about this here: > http://compilers.iecc.com/comparch/article/98-07-134
The inf behaviour is fine (inf != inf only when you start talking about aleph levels, and IEEE 754 doesn't handle those). It's specifically `nan` that is problematic, as it is one of the very few cases that breaks the reflexivity of equality. That said, the current behaviour was chosen deliberately so that containers could cope with `nan` at least somewhat gracefully: http://bugs.python.org/issue4296 Issue 10912 added an explicit note about this behaviour to the 3.x series documentation, but that has not as yet been backported to 2.7 (I reopened the issue to request such a backport). Cheers, Nick. -- Nick Coghlan | ncogh...@gmail.com | Brisbane, Australia _______________________________________________ Python-Dev mailing list Python-Dev@python.org http://mail.python.org/mailman/listinfo/python-dev Unsubscribe: http://mail.python.org/mailman/options/python-dev/archive%40mail-archive.com