[sugar] Python coding conventions

[Ian Bicking]

Marco Pesenti Gritti wrote:
> Eeeeh here comes my hate for python imports. What I'd really want in the 
> code is:
> 
> from sugar import presence
> 
> ps = presence.PresenceService()
> 
> Now, is there a way to get that without stuffing all the presence 
> service in presence.py. Or more in general can you elaborate on a way to 
> organize code in python that doesn't suck :) I guess we have been trying 
> to emulate java like packaging with generally one class per file, but 
> that doesn't seem to play well with python imports.
> 
> Anyway it would be great to solve this in a good way. I hate what we 
> have currently.

You can put everything in presence/__init__.py.  I don't like using 
__init__.py this way, though; it's a little quirky as a file 
(ImportError's in it are swallowed), and by itself it has a rather 
ambiguous name.  So I typically put something like this in there:

   # presence/__init__.py
   from presenceservice import PresenceService

Then you can do "from presence import PresenceService".  When you then 
try to track down PresenceService you'll have a little indirection, but 
usually it's not too distracting.

One downside is that there is then no way to import (and hence load) 
some of the code without importing all of it.  I.e., if you wanted 
access to something in presence/ but not PresenceService, you would end 
up implicitly importing PresenceService whether you wanted to or not.


-- 
Ian Bicking | ianb at colorstudy.com | http://blog.ianbicking.org