[Python-Dev] readd u'' literal support in 3.3?

Tres Seaver tseaver at palladion.com
Wed Dec 14 17:33:32 CET 2011

Hash: SHA1

On 12/14/2011 04:15 AM, "Martin v. Löwis" wrote:

>> It's "pure" in being optimized for a world where you just stop
>> using Python 2 one day, and start using 3 the next, without any
>> crossover support.
> That's not true. 2to3 is well suited for supporting both 2 and 3 from 
> the same code base, and reduces the number of compromises you have to 
> make compared to an identical-source approach (more dramatically so if
> you also want to support 2.5 or 2.4).
>> Anyway, if you're supporting both 2 and 3, a common code base
>> offers many attractions, so if it can be done, it will.
> And 2to3 is a good approach to maintaining a common code base.

Not in the experience of the folks who are actually doing that task:  the
overhead of running 2to3 every time 'setup.py develop' etc. runs dooms
the effort.  For instance, we have a report that the 2to3 step takes more
than half an hour (on at least one user's development machine) when
installing / refreshing zope.interface in a Python 3.2 virtualenv.  (Note
that I'm in the process of getting that package's unit test coverage up
to snuff before ripping out the 2to3 support in favor of a subset).

Using 2to3 during ongoing development makes Python feel like Java/C++,
where "get a cup of coffee while we rebuild the world" is a frequent

- -- 
Tres Seaver          +1 540-429-0999          tseaver at palladion.com
Palladion Software   "Excellence by Design"    http://palladion.com
Version: GnuPG v1.4.10 (GNU/Linux)
Comment: Using GnuPG with Mozilla - http://enigmail.mozdev.org/


More information about the Python-Dev mailing list