On Tue, 2005-10-04 at 08:32, Steve Holden wrote: > Carsten Haese wrote: > > On Mon, 2005-10-03 at 17:37, Steve Holden wrote: > > > >>Carsten Haese wrote: > >> > >>>On Mon, 2005-10-03 at 16:41, Carsten Haese wrote: > >>> > >>> > >>>>On Mon, 2005-10-03 at 15:52, Jacob Kroon wrote: > >>>> > >>>> > >>>>>Hi, I'm having some problems with implementing dynamical module loading. > >>>>>First let me > >>>>>describe the scenario with an example: > >>>>> > >>>>>modules/ > >>>>> fruit/ > >>>>> __init__.py > >>>>> apple.py > >>>>> banana.py > >>>>> > >>>>>apple.py defines a class 'Apple', banana defines a class 'Banana'. The > >>>>>problem lies in the > >>>>>fact that I want to be able to just drop a new .py-file, for instance > >>>>>peach.py, and not change > >>>>>__init__.py, and it should automatically pickup the new file in > >>>>>__init__.py. I've come halfway > >>>>>by using some imp module magic in __init__.py, but the problem I have is > >>>>>that the instantiated > >>>>>objects class-names becomes fruit.apple.Apple/fruit.banana.Banana, whild > >>>>>I want it to be > >>>>>fruit.Apple/fruit.Banana. > >>>>> > >>>>>Is there a smarter way of accomplishing what I am trying to do ? > >>>>>If someone could give me a small example of how to achieve this I would > >>>>>be very grateful. > >>>> > >>>>How about something like this in fruit/__init__.py: > >>>> > >>>>import os > >>>> > >>>>fruit_dir = os.path.dirname(__file__) > >>>>fruit_files = [x for x in os.listdir(fruit_dir) if (x[-3:]=='.py' and > >>>>x!='__init__.py')] > >>>>for fruit_file in fruit_files: > >>>> module_name = fruit_files[:-3] > >>> > >>> ^^^^^^^^^^^ This should be fruit_file, of course. > >>> > >>> > >>> > >>>> exec "from %s import *" % module_name > >>>> > >> > >>Wouldn't > >> > >> __import__(module_name) > >> > >>be better. > > > > > > I don't see how a working example that meets the OP's requirements can > > be constructed using __import__, but that may easily be due to my lack > > of imagination. How would you do it? > > > I was simply suggesting that you replace the exec statement with a call > to __import__(). Wouldn't that work?
Not the way I tried it by simply replacing my line with your line. (If it matters, I'm on python 2.2 here.) First of all, the __import__ variant doesn't see the submodules unless I add fruit_dir to sys.path. Secondly, the OP's requirements are that the classes that the submodules implement be imported into fruit's namespace, and I don't see how to make __import__ do that. Regards, Carsten Haese. -- http://mail.python.org/mailman/listinfo/python-list
