Armin Rigo <[EMAIL PROTECTED]> wrote: > Hi Martin, > On Sat, Nov 04, 2006 at 04:47:37PM +0100, "Martin v. L?wis" wrote: > > Patch #1346572 proposes to also search for .pyc when OptimizeFlag > > is set, and for .pyo when it is not set. The author argues this is > > for consistency, as the zipimporter already does that. > > My strong opinion on the matter is that importing a .pyc file if the .py > file is not present is wrong in the first place. It caused many > headaches in several projects I worked on. > > Typical example: someone in the project removes a .py file, and checks > in this change; someone else does an 'svn up', which kills the .py in > his working copy, but not the .pyc. These stale .pyc's cause pain, e.g. > by shadowing the real module (further down sys.path), or simply by > preventing the project's developers from realizing that they forgot to > fix some imports. We regularly had obscure problems that went away as > soon as we deleted all .pyc files around, but I cannot comment more on > that because we never really investigated.
I had a very similar problem the other week when mucking about with a patch to ntpath . I had it in a somewhat small temporary projects folder and needed to run another project. It picked up the local ntpath.py when importing path.py, but then failed because I was working on a 2.5 derived ntpath, but I was using 2.3 to run the other project. After renaming the local ntpath, I continued to get the error until I realized "damn pyc" and was halfway through a filsystem wide search for the problem code (10 minutes elapsed). About the only place where I have found the need for pyc-without-py importing is for zipimports, specifically as used by py2exe and other freezing applications. I don't know if we want to add a new command line option, or a __future__ import, or something, but I think there should be some method of warning people that an import was performed without source code. - Josiah _______________________________________________ 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
