[Python-Dev] Why is nb_inplace_power ternary?

["Martin v. Löwis"]

Raymond Hettinger schrieb:
> That made sense, but my question was whether there would be benefit
> to making the change in the middle of a major release.  At worst, code 
> that is
> currently working due to undefined behavior will stop working.   I don't
> see any offsetting benefit.  ISTM that Py2.5 should be left as-is and that
> the full signature change be made in Py2.6.

I can't see "left as is" as an option, see #1648268 and #1653736. 
Apparently, there are platforms where the code traps when there
is a signature mismatch.

If raising an exception is unacceptable, I'd rather explicitly ignore
the extra argument, instead of ignoring it implicitly.

Regards,
Martin