[Python-Dev] a strange case

[Phillip J. Eby]

At 01:45 PM 5/16/03 -0800, Troy Melhase wrote:
> >     Jeremy> I think we decided this wasn't a pure bugfix :-).  Some poor
> >     Jeremy> soul may have code that relies on being able to subclass a
> >     Jeremy> module.
> >
> > How about at least deprecating that feature in 2.2.3 and warning about it
> > so that poor soul knows this won't be supported forever?
>
>I think I'm knocking on the poor-house door.
>
>Just last night, it occurred to me that modules could be made callable via
>subclassing.

This isn't about subclassing the module *type*, but about subclassing 
*modules*.  Subclassing a module doesn't do anything useful.  Subclassing 
the module *type* does, as you demonstrate.

Python 2.3 still allows you to subclass the module type, even though it 
does not allow you to subclass modules.

Now, if you *really* want to subclass a *module*, then you should check out 
PEAK's "module inheritance" technique that lets you define new modules in 
terms of other modules.  It's useful for certain types of AOP/SOP 
techniques.  But it's currently implemented using bytecode hacking, and is 
therefore evil.  ;)  Anyway, it doesn't rely on actually *subclassing* modules.

Speaking of bytecode hacking, it would be so much easier to implement 
"portable magic" if there were a fast, easy to use, language-defined 
intermediate representation for Python code that one could hack with.  And 
don't tell me to "use Lisp", either...  ;)