(Thank you, by the way, for actually reading some of the documentation before writing this post, and for asking questions instead of jumping to conclusions.)
At 06:43 PM 4/28/2006 +0200, M.-A. Lemburg wrote: >I've now found this section in the documentation which seems to >have the reason: > >http://peak.telecommunity.com/DevCenter/EasyInstall#compressed-installation > >Apart from the statement "because Python processes zipfile entries on >sys.path much faster than it does directories." being wrong, Measure it. Be sure to put the directories or zipfiles *first* on the path, not last. The easiest way to do so accurately would be to easy_install some packages first using --zip-ok and then using --always-unzip, and compare the two. Finally, try installing them --multi-version, and compare that, to get the speed when none of the packages are explicitly put on sys.path. >it looks like all you'd have to do, is make --always-unzip the >default. You mean, all that *you'd* have to do is put it in your distutils configuration to make it the default for you, if for some reason you have a lot of programs that resemble "python -c 'pass'" in their import behavior. :) >Another nit which seems to have been introduced in 0.6a11: >you now prepend egg directory entries to other sys.path entries, >instead of appending them. > >What's the reason for that ? It eliminates the possibility of conflicts with system-installed packages, or packages installed using the distutils, and provides the ability to install stdlib upgrades. >Egg directory should really be treated just like any other >site-package package and not be allowed to override stdlib >modules and packages Adding them *after* site-packages makes it impossible for a user to install a local upgrade to a system-installed package in site-packages. One problem that I think you're not taking into consideration, is that setuptools does not overwrite packages except with an identical version. It thus cannot replace an existing "raw" installation of a package by the distutils, except by deleting it (which it used to support via --delete-conflicting) or by installing ahead of the conflict on sys.path. Since one of the problems with using --delete-conflicting was that users often don't have write access to site-packages, it's far simpler to just organize sys.path so that eggs always take precedence over their parent directory. Thus, eggs in site-packages get precedence over site-packages itself, and eggs on PYTHONPATH get precedence over PYTHONPATH. >without explicit user action by >e.g. adjusting PYTHONPATH. Installing to a PYTHONPATH directory *is* an explicit user action. Installing something anywhere is an explicit user request: "I'd like this package to be importable, please." If you don't want what you install to be importable by default, use --multi-version, which installs packages but doesn't put them on sys.path until you ask for them at runtime. _______________________________________________ Python-Dev mailing list Python-Dev@python.org http://mail.python.org/mailman/listinfo/python-dev Unsubscribe: http://mail.python.org/mailman/options/python-dev/archive%40mail-archive.com
