[Bf-python] Memory bug in Bpy api

[Willian Padovani Germano]

Hi,

One thing has nothing to do with the other:

Global dicts:

Each script in Blender has its own global dictionary, that gets deleted 
when the script finishes executing (GUI scripts and also those who call 
the file selector leave callbacks, so we postpone removing their global 
dicts until they are really finished). This keeps things clean, with one 
script not affected by another's namespace.

Note: among other changes, after 2.41 I plan to keep the global dicts of 
script links (including space handlers) around, to make writing these 
scripts easier and running them faster. Each will still have its own 
global dict (that gets cleaned (deleted) when an error occurs), so no 
namespace issues still.

Modules:

Python modules are not reloaded unless you specifically tell the 
interpreter to do so.

To solve the problem of vars created in modules being persistent, simply 
*do not use modules to store new data* -- do not do this:

import math
math.myvar = <something>
math.myfunction = f
#etc

Use the Registry dict, use a Blender text, save data as a file (the 
Registry can do this for you). Storing vars in default modules like 
math, etc. is like adding new vars or functions to a system library.

Besides not being a clean way to code, it also pollutes the modules that 
other scripts will use. Imagine if many authors start doing this, soon 
one script will change the data created by another and cause trouble.

Saving GUI buttons in modules would be even more troublesome, these 
don't stay around for that long, Blender recreates buttons on every 
redraw. That's why they should be created in the draw callback that you 
register with Draw.Register.

--
Willian