Question about 'None'

Steven Bethard steven.bethard at
Thu Jan 27 16:15:30 EST 2005

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.


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