At 09:13 PM 7/12/2007 -0700, Andy C wrote: >I can definitely see why it "just makes sense", and my first thought >was indeed to name it __main__. But then you lose the ability to make >a distinction: What does "if __name__ == '__main__" mean in >__main__.py? : )
The same as anywhere else; it'll just always be true. :) > If someone tries does import __main__ from another >module in the program, won't that result in an infinite loop? No, for two reasons. First, importing __main__ always returns whatever the start script is using as a __main__ module. Second, even if you're in the middle of __main__ itself, the module is already in sys.modules. So this is a non-issue. >At Google some people do "import sitecustomize" and get values that >were computed earlier by the sitecustomize. I could see the same kind >of thing happen with __main__.py. Yes, but it won't work unless the overall program was launched via *that particular* __main__.py -- running from the interpreter prompt for example, those values won't be there. So, people will learn quickly why that doesn't work. > > Testing your package before you zip it, would be one. :) My > > personal main interest was in being able to add an item to sys.path > > without having to set $PYTHONPATH on Windows. That's why I'd like it > > to be possible to use -z more than once (or whatever the option > ends up as). > >Where would you do that? Just typing it literally on the command >line? Yes. > > > I think it's sufficient to treat it as a documented "trick" > > >that you can substitute a whole directory for a zip file with the -z > > >flag. If there is a concrete suggestion, I'd like to discuss it, but > > >otherwise it seems like we'll get bogged down in expanding use cases. > > > > Eh? First you say there aren't any use cases, now you say there'll be > > too many? I'm confused. The only competing proposal besides what > > I've suggested was the one to add an option to "runpy", and IMO > > that's dead in the water due to shebang argument limits. > >As implemented the patch is fairly simple, and shouldn't have any >unintended consequences. I'm not necessarily opposed to making it >more general and thinking about sys.path vs. a zip file specifically. I think it can be replaced with using standard importer detection of sys.argv[0], to decide whether it is an importable location (dir/zip), and then importing __main__, with fallback to the old script behavior. This is forward-compatible with other import mechanisms, and supports #! lines better for zipfiles, since no -z option is needed. _______________________________________________ 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
