[Python-Dev] sum(...) limitation

[Stephen J. Turnbull]

Ethan Furman writes:
 > On 08/11/2014 08:50 PM, Stephen J. Turnbull wrote:
 > > Chris Barker - NOAA Federal writes:
 > >
 > >> It seems pretty pedantic to say: we could make this work well,
 > >> but we'd rather chide you for not knowing the "proper" way to do
 > >> it.
 > >
 > > Nobody disagrees.  But backward compatibility gets in the way.
 > 
 > Something that currently doesn't work, starts to.  How is that a
 > backward compatibility problem?

I'm referring to removing the unnecessary information that there's a
better way to do it, and simply raising an error (as in Python 3.2,
say) which is all a RealProgrammer[tm] should ever need!

That would be a regression and backward incompatible.