[Python-Dev] Coercion and comparison of numbers

[Guido van Rossum]

> I just received a bug report for mx.Number which revealed a
> probelm with the comparison code in Python 2.1. Looking at
> the code it seems that one of my original coercion patches
> did not make it into the core. I added a new API PyNumber_Compare()
> knows about the new coercion mechanism and should be called for
> numbers instead of trying coercion in PyObject_Compare().
> 
> Was this part of the coercion patch left out on purpose or
> a simple oversight ? I hope the latter... 

Hard to say.  I don't think I paid very close attention to your patch;
Neil did, but I changed a lot of the code around coercions and
comparisons in order to implement rich comparisons.  So, several
things may have happened: Neil lost it; Neil decided against it; or I
ripped it out.

Can you elucidate me regarding the issues?  (If there's code, please
quote it or link to a specific patch.)  Since the concept of "number"
is ill-defined at best, when exactly should PyNumber_Compare() be
called?  What is it supposed to do?  Does it need a rich cousin?

--Guido van Rossum (home page: http://www.python.org/~guido/)