On Mon, Oct 8, 2012 at 11:49 PM, Mark Dickinson firstname.lastname@example.org wrote:
On Tue, Oct 9, 2012 at 7:44 AM, Guido van Rossum email@example.com wrote:
This smells like a bug in the != operator, it seems to fall back to not == which it didn't used to. More later.....
I'm fairly sure it's deliberate, and has been this way in Python for a long time. IEEE 754 also has x != x when x is a NaN (at least, for those IEEE 754 functions that return a boolean rather than signaling an invalid exception), and it's a well documented property of NaNs across languages.
Yeah, sorry, I misremembered. :-) This does mean we need to update the text Ned is proposing.