[Jython-dev] python modules within jarfiles revisited

[Ted B. <te...@et...>]

Background:
I'm distributing a java application in executable jar format.  My goal is to 
offer python as a scripting engine for the application, and to that end I 
wish to distribute the jython Lib/ modules as part of the jar, such that user 
scripts can import these modules.

1. Modules in the root directory of the jar may be imported normally
2. Modules in a subdirectory of the jar may be imported iff a __init__.py 
module also appears in that subdirectory.
3. Attempts to import modules from a subdirectory without a corresponding 
__init__.py file yield a "ImportError: no module named X" exception, where X 
is the subdirectory.

I assume this is because /path/to/jarfile is a valid addition to the sys.path 
and /path/to/jarfile!/subdirectory is not a valid addition and is ignored.

Am I correct in also assuming that the __init__.py file causes the python 
interpreter to treat the *directory* as a module itself?  If this is the 
case, why does an __init__.py placed in the jar root directory not get 
executed, allowing me to import subdirectories without the need for 
__init__.py files in them?  

Honestly, this isn't a really big deal.  It makes for some strange looking 
import clauses if you're used to CPython ( from Lib import string ), but it 
does the job.  My biggest concern was a desire to modify the Lib/ tree as 
little as possible, not at all being my preference.  I know little enough 
about hard-core python hacking that I didn't want to mess with anything.

Ted