PYTHONPATH problem: how to deal with?

[jerome.marant@free.fr (Jérôme Marant)]

Hi,

  I am the python-unit maintainer (upstream program called PyUnit)
  for python 1.5 and 2.0.
  PyUnit has been included in Python 2.1. but I won't give it away
  since it does evolve separately from Python releases.

  However, because of PYTHONPATH, the latest version of the module
  will never be loaded by the interpreter.

  In 2.0 (and quite the same in 2.1), PYTHONPATH looks like:

  amboise:~$ python2 -c 'import sys; print sys.path'
  ['',
   '/usr/lib/python2.0',
   '/usr/lib/python2.0/plat-linux2',
   '/usr/lib/python2.0/lib-dynload',
   '/usr/local/lib/python2.0/site-packages',
   '/usr/local/lib/site-python',
   '/usr/lib/python2.0/site-packages',
   '/usr/lib/site-python']

  So, if the interpreter find the module in its core modules, it
  will never see that a newer version of the module was installed
  in site-packages.

  Usually, packages installed separately (site-packages) from the
  core python modules are more recent that the same modules of
  the core, because they evolve faster than python releases.
  Manual installations of modules (/usr/local) are usually done
  when packages are not up-to-date, so more recent than site modules.

  This is a well known problem since python-xml (PyXML) is both
  in 2.0 core and in a separate package and PyXML people have
  implemented an ugly hack to work this around.

  So, I'm proposition to reorganize the PYTHONPATH like this :

  ['',
   '/usr/local/lib/python2.0/site-packages',
   '/usr/local/lib/site-python',
   '/usr/lib/site-python'
   '/usr/lib/python2.0/site-packages',   
   '/usr/lib/python2.0',
   '/usr/lib/python2.0/plat-linux2',
   '/usr/lib/python2.0/lib-dynload',
   
  ] 

  I know that it could lead to some problems but not
  that much I think.

  Thanks in advance for your comments.

  PS: it would be usefull to talk to Brendan O'Dea who chose the
  same ordering for Perl packages.

-- 
Jérôme Marant <jerome.marant@free.fr>