On 24/09/2014 11:54, Mark Dickinson wrote:
> 
> Mark Dickinson added the comment:
> 
>> Well we will just have to agree to disagree on this :-)
> 
> Sure.  In the mean time, would you be interested in writing a patch targeting Python 3.5?  (Irrespective of the arguments about the definition, I don't think this is a change that could be applied in a 3.4 bugfix release.)

Yes, I am very willing to contribute. But I have never contributed to
Python before and I almost certainly have a lot to learn in any attempt
to do this.

In particular, I need advice on where any gcd should go (fractions or
math or ...).  And if it goes in math and/or we want to speed it up, I
would have to learn how to integrate Python and C code (I have done
almost none of this before).

So I would much appreciate further discusssion of this possible change
and how best to implement it (if there is a consensus to do so).

Of course, there is the very simple change of adding abs(x) to the
return value for the current gcd and adjusting its single use in
fractions accordingly.  But since there is already concern about the
impact of the gcd on the performance of fractions, it deserves more
careful consideration than this approach would involve.