Question about 'None'

[Francis Girard]

Very complete explanation.
Thank you

Francis Girard

Le jeudi 27 Janvier 2005 22:15, Steven Bethard a écrit :
> Francis Girard wrote:
> > I see. There is some rule stating that all the strings are greater than
> > ints and smaller than lists, etc.
>
> Yes, that rule being to compare objects of different types by their type
> names (falling back to the address of the type object if the type names
> are the same, I believe).  Of course, this is arbitrary, and Python does
> not guarantee you this ordering -- it would not raise backwards
> compatibility concerns to, say, change the ordering in Python 2.5.
>
> > What was the goal behind this rule ?
>
> I believe at the time, people thought that comparison should be defined
> for all Python objects.  Guido has since said that he wishes the
> decision hadn't been made this way, and has suggested that in Python
> 3.0, objects of unequal types will not have a default comparison.
>
> Probably this means ripping the end off of default_3way_compare and
> raising an exception.  As Fredrik Lundh pointed out, they could, if they
> wanted to, also rip out the code that special-cases None too.
>
> Steve