David T. Lewis wrote:
> Is there an explanation somewhere (swiki, prior message on the list,
> etc) that explains how this might be done? I'm asking only out of
> curiosity. This issue has been around for a long time, and I assumed
> that it must be a really hard problem to solve or someone would have
> done so by now.

The main thing that got adopted from Anthony is the way he represented 
proper closures. I don't remember the exact details but it has been 
worked out and if you need inspiration just look at the new compiler ;-)

Cheers,
   - Andreas