>> Again, django has been ported to python 3, that's fine, everybody >> acknowledges that, but it's not the case that one code base works with >> both python versions. > > Well, if the port is done via 2to3, you can install the same code base in > Python 2 and Python 3, and the distutils install mechanism will run an > automated transformation over the code during the installation. If there is > no manual interaction required to run the code on both platforms, I would > say that qualifies as "one code base works with both Python versions". It's > not different from generating code or specialised config files during the > installation or similar things.
This is all true, but what we were talking about is not exactly this, but rather having a single code base running unmodified on python 2 and 3. Another poster actually supplied an example: crunchy. > > I think django and cheetah > > doesn't count because they simply take their python 2 code, run it > > through 2to3 which gives them a python 3 code (I could be wrong > > though). Two codes for the two python versions. > > But just one code base that has to be maintained. And I think the > maintenance is the main aspect here. This is true again. But where it all started is Alf's sentence in his book. And I think he has a point there, it might be possible to do this (single code base for both versions), but it's not easy. >> Just to be clear I'm looking for an example where one given >> code runs on python 2 and 3 unmodified. > > lxml for example. Not only the Cython compiled part (which is automatically > portable anyway), also all of its Python code base and its entire test > suite. It runs on all Python versions from 2.3 through 3.1, and it doesn't > use 2to3 or any other kind of code modification. > > The regular Python code base was almost trivial to port, but porting the > test suite was actually quite involved. The main reasons for that were a) > doctests and b) the requirement to test exactly string input/output and > exactly unicode input/output on both platforms. Most code simply doesn't > have that requirement, but lxml does. Cool, that's another example I was unaware of, thanks! Cheers, Daniel -- Psss, psss, put it down! - http://www.cafepress.com/putitdown -- http://mail.python.org/mailman/listinfo/python-list
