Python 3.0 - is this true?

[George Sakkis]

On Nov 11, 8:02 am, "M.-A. Lemburg" <m... at egenix.com> wrote:
> On 2008-11-11 02:10, Steven D'Aprano wrote:
>
> > On Mon, 10 Nov 2008 12:51:51 +0000, Duncan Grisby wrote:
>
> >> I have an object database written in Python. It, like Python, is
> >> dynamically typed. It heavily relies on being able to sort lists where
> >> some of the members are None. To some extent, it also sorts lists of
> >> other mixed types. It will be very hard to migrate this aspect of it to
> >> Python 3.
>
> > No, it is "very hard" to sort *arbitrary* objects consistently. If it
> > appears to work in Python 2.x that's because you've been lucky to never
> > need to sort objects that cause it to break.
>
> If you read Duncan's email, he isn't talking about arbitrary objects
> at all. He's just referring to being able to sort lists that contain
> None elements.
>
> That's far from arbitrary and does work consistently in Python 2.x -
> simply because None is a singleton which is special cased in Python:
> None compares smaller to any other object in Python.
>
> I'm not sure why this special case was dropped in Python 3.0. None
> is generally used to be a place holder for a n/a-value and as
> such will pop up in lists on a regular basis.
>
> I think the special case for None should be readded to Python 3.0.

On python-ideas I proposed adding two new builtin singletons instead,
Smallest and Largest, since the behavior of None wrt comparisons was
never officially part of the language.

George