Multirelease effort: Moving to Python 3

[Pierre-Yves Chibon]

On Tue, 2013-07-23 at 02:40 -0400, Bohuslav Kabrda wrote:
> > python2 and python3 are separate languages.  There is a lot of
> similarity
> > between the two and with recent enough versions of python2 (2.7) and
> python3
> > (python3.4) and some external libraries (python-six) and by sticking
> to some
> > specific coding styles ( http://python3porting.com/noconv.html ) and
> by
> > sometimes resorting to having separate files for some
> python2-specific
> > routines vs python3-specific routines you can write code that is
> valid and
> > runs under either language.  That does not mean that they are the
> same
> > language.
> > 
> 
> The problem is that you're basically saying "my mental model is the
> right one", which is not necessarily true for everyone (and not
> necessarily true generally). Taking your arguments a bit further,
> Python 2.6 and 2.7 are different languages too, since there are some
> backward incompatible additions to Python 2.7.

Python 2.7 might not be backward compatible with 2.6 or 2.5 but 2.5 and
2.6 is forward compatible with 2.7, which is not true for python 2.* vs
3.*.

That makes them more of different languages than 2.6 vs 2.7.

Pierre