> From: Mats Nygren <nygren at sics.se>

> I'm considering implementing a simple CLOS-like language.  
Primarily to get
> some experience in this, following "The art of the MOP".

Great!

> And then try it out with some metaobjects for objects with  
history. Objects
> with history can be used as a basis for editors with indefinite  
history and
> also for backtracking search, together with unification that will  
provide a
> Prolog-system within the MOP. I dont know in advance how feasible  
this is
> it seems within reach.

Interesting, an 'object-space' approach to backtracking / Prolog.   
All the approaches I've are 'code-space', and that has probably  
restricted my thinking in that regard, so I'd be glad to find out  
more.  Anyway, are you aware of the bactracking-extension to  
Smalltalk (without kernel support)?  It was an OOPSLA paper a while  
back, and I put the code in Squeak last summer.

Marcel