[Python-Dev] 2.7 Release? 2.7 == last of the 2.x line?

[Eric Smith]

Martin v. Löwis wrote:
>> Mike Krell wrote:
>>>     Well, 3to2 would then be an option for you: use Python 3 as the source
>>>     language.
>> Making life easier for 3to2 is an *excellent* rationale for backports.
>>
> 
> I'm skeptical. If new features get added to 2.7: why would that simplify
> 3to2? It couldn't *use* these features, since it surely would have to
> support 2.6 and earlier as well.
> 
> Not sure what 3to2 would do about difficult-to-convert 3.x feature (as,
> perhaps, the nonlocal keyword). If it currently gives up, it then may
> offer you to restrict your target versions to 2.7+. Not sure whether
> users would use that option, though - perhaps they rather stop using
> nonlocal in 3.x if 3to2 cannot support it for all 2.x versions they are
> interested in.

But surely someday 2.7 will be the oldest targetted 2.x version of 
Python for 3to2 and other tools (regardless of whether there's a 2.8). 
When that day comes, 3to2 can be made simpler, or can increase the 
amount of Python 3.x it can convert (or both) if we add 3.x features to 2.7.

Of course, planning for a time so far in the future is difficult, and 
possibly pointless.