Re: [Python-Dev] People want CPAN :-)

[ I'm posting this comment in reply to seeing this thread: * http://thread.gmane.org/gmane.comp.python.distutils.devel/11359 Which has been reposted around - and I've read that thread. I lurk on this list, in case anything comes up that I'd hope to be able to say something useful to. I don't know if this will be, but that's my reason for posting. If this is the wrong place, my apologies, I don't sub to distutils-sig :-/ ] On Sat, Nov 7, 2009 at 2:30 PM, ssteinerX@gmail.com wrote:

On Nov 7, 2009, at 3:20 AM, Ben Finney wrote:

...

Guido van Rossum writes:

...

On Fri, Nov 6, 2009 at 2:52 PM, David Lyon wrote:

...

[ lots of snippage ] ... All in all, I think this could be a big leap forward for the Python distribution ecosystem whether or not we eventually write the PyPan I wished for as a new Perl refugee.

Speaking as someone who left the perl world for the python world, many years ago now, primarily due to working on one project, the thing I really miss about Perl is CPAN. It's not the fact that you know you do perl Makefile.PL && make && make test && make install. Nor the fact that it's trivial to set up a skeleton package setup that makes that work for you. It's not the fact that there's an installer than can download & track dependencies. The thing that makes the difference IMHO is two points: * In a language which has a core ethos "There's more than one way to do it", packaging is the one place where there is one, and only one obvious way to do it. (Oddly with python, with packaging this is flipped - do I as a random project use distutils? pip? setuptools? distribute? virtualenv?) * It has a managed namespace or perhaps better - a co-ordinated namespace. CPAN may have lots of ills, and bad aspects about it (I've never really trusted the auto installer due to seeing one too many people having their perl installation as a whole upgraded due to a bug that was squashed 6-8 years ago), but these two points are pretty much killer. All the other aspects like auto download, upload, dependency tracking, auto doc extraction for the website etc, really follow from the managed namespace really. I realise that various efforts like easy_install & distribute & friends make that sort of step implicitly - since there can only be one http://pypi.python.org/pypi/flibble . But it's not quite the same - due to externally hosted packages. For more detail about this aspect: * http://www.cpan.org/modules/04pause.html#namespace I'm really mentioning this because I didn't see it listed, and I really think that it's very easy to underestimate this aspect of CPAN. IMHO, it is what matters the most about CPAN. The fact that they've nabbed the CTAN idea of having an archive network for storing, mirroring and grabbing stuff from is by comparison /almost/ irrelevant IMHO. It is the sort of thing that leads to the DBI::DBD type stuff that is being simple to use, because of the encouragement to talk and share a namespace. The biggest issue with this is retrofitting this to an existing world. Personal opinion, I hope it's useful, and going back into lurk mode (I hope :). If this annoys you, please just ignore it. Michael.