* Thomas Rachel (Sat, 28 May 2011 07:06:53 +0200) > Am 27.05.2011 17:52 schrieb Steven D'Aprano: > > On Fri, 27 May 2011 09:40:53 -0500, harrismh777 wrote: > >> 3.x is completely incompatible with 2.x (some call it a dialect, > >> but that is a lie). > > > > "Completely incompatible"? A "lie"? > > Hard word, but it is true. Many things can and will fall on your feet > when moving.
I think we should stop talking about (in)compatability because everyone seems to associate something different with that term (incompatible = "no Python2 to code will run with Python3", "not all Python2 code will run with Python3"). The question is: if you want (or have) to run your code under Python3, how likely is that it will run unmodified? My experience is: unless the code is especially written with Python3 compatability or just a short snippet, it's actually quite unlikely that it will run. I modified three programs/modules (none of them written with Python3 in mind - I was thinking that Python 3000 would come out some day after Perl 6, PHP 6 and GNU Hurd; how could I know that the Python developers actually mean business?) One is a tool box kind of module. I had to insert lots of "list()" and add a complete function that would deal with the different behaviour of "sort". Probably easy to find the problems if you have extensive unit tests but without it was a tedious nightmare. The second a kind of script template. gettext.install has no "unicode = True". Easy fix but I wondered why Python 3 does not ignore the keyword simply. The third, a more real world complete application using PyQt. Took me about a day to fix. The problem was not just with the code but also with the tools (pyuic4, pyrcc4). Without the PyQt mailing list this wouldn't have been possible. Still: a complete workday (or even more) for 150 lines of code. Thorsten -- http://mail.python.org/mailman/listinfo/python-list
