[Python-Dev] a strange case (original) (raw)

Phillip J. Eby pje@telecommunity.com
Fri, 16 May 2003 19:48:21 -0400

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... ;)