Folks: There are two things that cause a lot of people to object to the use of setuptools: that it changes the semantics of PYTHONPATH, making it impossible to override packages on the command-line, and that it doesn't work when you run "setup.py install --prefix=./some_dir". This patch addresses the first one. Currently, if you ever allow setuptools to write into your system directory (e.g. /usr/lib/python2.5/site-packages) then it will install a .pth file which changes the behavior of PYTHONPATH. This will prevent you from over-riding the installed package with a specific package on the command-line, such as: PYTHONPATH=./that-version-of-Twisted/ python ./my_script.py Many people find this behavior of setuptools objectionable [1, 2, 3, plus personal correspondance when I did my "Why do you hate setuptools?" survey]. Fortunately it seems possible to preserve the precedence of PYTHONPATH modules while still having installed eggs override installed non-eggs, as motivated in [4]. Sat Nov 15 11:59:32 MST 2008 zooko@zooko.com * leave the PYTHONPATH dirs at the front of the sys.path This is in accordance with http://www.python.org/doc/2.5.2/inst/search-path.html , which says "The PYTHONPATH variable can be set to a list of paths that will be added to the beginning of sys.path.", and it resolves an objection many people have which impels them to ban setuptools from systems they administrate. --- old-dw-0.6c9/setuptools/command/easy_install.py +++ new-dw-0.6c9/setuptools/command/easy_install.py @@ -1364,7 +1364,7 @@ "%s\n" "import sys; new=sys.path[sys.__plen:];" " del sys.path[sys.__plen:];" - " p=getattr(sys,'__egginsert',0); sys.path[p:p]=new;" + " p=getattr(sys,'__egginsert',len(os.environ.get ('PYTHONPATH','').split(os.pathsep))); sys.path[p:p]=new;" " sys.__egginsert = p+len(new)\n" ) % data Regards, Zooko --- http://allmydata.org -- Tahoe, the Least-Authority Filesystem http://allmydata.com -- back up all your files for $10/month [1] http://mail.python.org/pipermail/distutils-sig/2006-July/006492.html [2] https://www.dfwpython.org/pipermail/dfwpython/2007-June/000756.html [3] http://www.rittau.org/blog/20070726-02 [4] http://mail.python.org/pipermail/python-dev/2008-March/077918.html