> However, I think that a generalized framework for capturing state changes and applying them later is a Very Hard Problem. It might be possible if you implemented a new Smalltalk with transactional semantics like Gemstone: commit and abort operations, and a third operation to abort-but-create-a-change-set.

In fact it is quite simple to do at the image level:

    http://scg.unibe.ch/archive/papers/Reng08aTransMemory.pdf

I haven't tested the implementation on installing code though. The
problem is that this involves quite some primitives that need to be
handled differently.

Lukas

-- 
Lukas Renggli
http://www.lukas-renggli.ch