<target name="codegen">
   
   <!-- if there's an old one, delete it.-->
   <delete file="fileList.txt" if="${file::exists('fileList.txt')}"/>      
   
   <!-- generate the new file list -->
   <foreach item="File" property="filename"> 
      <in> 
         <items>
            <include name="**.cs" />
            <include name="**.js" />
            <include name="**.xul" />
         </items> 
      </in> 
      <do> 
         <echo file="fileList.txt" message="${filename}" append="true"/>
      </do> 
   </foreach>
   
   <!-- pass the file list to Cog -->
   <exec program="python">
            <arg value="cog.py" />
            <arg value="-r" />
            <arg value="@fileList.txt" />
   </exec>
   
   <!-- clean up -->
   <delete file="fileList.txt" failonerror="true"/>
</target>   

The problem:

path

A list of strings that specifies the search path for modules. Initialized from the environment variable PYTHONPATH, plus an installation-dependent default.

As initialized upon program startup, the first item of this list, path[0], is the directory containing the script that was used to invoke the Python interpreter. If the script directory is not available (e.g. if the interpreter is invoked interactively or if the script is read from standard input), path[0] is the empty string, which directs Python to search modules in the current directory first. Notice that the script directory is inserted before the entries inserted as a result of PYTHONPATH.

A program is free to modify this list for its own purposes.

Changed in version 2.3: Unicode strings are no longer ignored.

The solution:

How we'll use it:

1. Putting everything in the path and praying to the gods of naming conflicts
   In python, you have a sys.path, which is analogous to your system PATH variables. Python will search the sys.path variable for the class or variable, just like running "cmd" on a DOS prompt searches the %PATH% until it finds cmd.exe. So, with that in mind, I put this at the top of every file:

   import sys
   sys.path.append('./')
   sys.path.append('../')
      

   That way, things are always visible. Of course, after importing a few files, the sys.path had multiple entries for './' and '../', which seemed really dirty. Also, we're moving to this language to get more dynamism, and copy/pasting the same line of code everywhere was kinda defeating the purpose. Also, if I ever wanted to use the same name in two places, it would have a conflict and die. So, I hit up some mailing lists and documentation, and came up with a slightly safer way.
2. Use a __init__.py to automatically add all the paths
   You can put a __init__.py in a directory, which makes that directory a package. In there I had a function that added a directory to sys.path, first checking if it existed already, so I wouldn't get any messy duplicates. This proved unreliable, and worked depending on where I started the python interpreter from. This also required copy/pasting about to ensure that all subdirectories would include everything properly. Still too much of a mess, so sent a request to the python tutor mailing list. After some helpful replies and sitting up with Nathan methodically testing things, we found something clean and promptly got drunk.
3. Use __init__.py files and the __all__ variable to specify the contents of a package, and import using the full dotted module name.
   By sticking a __init__.py in each directory, that enables me to use the path to the file as a way to identify it. So, with the file structure:
   • /One
     • __init__.py
     • A.py
   • /Two
     • __init__.py
     • B.py
   In file A.py, I can reference things in B.py by saying:

   import Two.B

   In a nutshell, we need to walk the namespace hierarchy and import each file, so we can define an __all__ in the __init__.py file, and use that for our reflective needs. See the python docs for more info on __all__.

>>>def doStuff():
      sumSquares = lambda x,y: x*x + y*y
      print sumSquares(1,1)
>>>doStuff()
2

>>>def addAttributes(h1, h2):
      append = lambda k,v: h1[k] = v
      [append(k,v) for k,v in h2.items()]