On 14 November 2011 08:18, Stefan Behnel <stefan...@behnel.de> wrote: > "Martin v. Löwis", 13.11.2011 21:46: >>> >>> I'm asking specifically because I'd like to properly implement __file__ >>> in Cython modules at module init time. >> >> Why do you need to implement __file__? Python will set it eventually to >> its correct value, no? > > Well, yes, eventually. However, almost all real world usages are at module > init time, not afterwards. So having CPython set it after running through > the module global code doesn't help much. >
Perhaps Cython could detect use of __file__ at module scope (if this package context function is not available), and if it's used it tries to use something akin to imp.find_module(__name__) to find the path to the file and set __file__ manually. It should handle dots out of the box and perhaps not rely on any __path__ attributes of packages (I think not many people change __path__ or use pkgutil anyway). Would this be feasible for python < 3.3? >>> Another problem is that package local imports from __init__.py no longer >>> work when it's compiled >> >> Does it actually work to have __init__ be an extension module? > > I'm just starting to try it, and the problems I found so far were __file__ > (in general), __path__ and relative imports (specifically). > > >>> Any ideas how this could currently be achieved? >> >> Currently, for Cython? I don't think that can work. > > Hmm, it might work to put an empty module next to the 'real' extension and > to import it to figure out the common directory of both. As long as it's > still there after installation and the right one gets imported, that is. A > relative import should help on versions that support it. Although that won't > help in the __init__ case because a relative import will likely depend on > __path__ being available first. Chicken and egg... > > Support in CPython would definitely help. > > >>> Or could this become a new feature in the future? >> >> Certainly. An approach similar to _Py_PackageContext should be possible. > > Yes, and a "_Py_ModuleImportContext" would be rather trivial to do. Could > that go into 3.3? What about 2.7? Could an exception be made there regarding > new "features"? It's not likely to break anything, but it would help Cython. > > Stefan > > _______________________________________________ > 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/markflorisson88%40gmail.com > _______________________________________________ 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
