token filters - ability to 'get' expressions, function bodies, ..

[askok@...]

Could the LHF/Silverstone token filter approach be 
extended to allow:

- getting the following expression (not just a token)
- getting the following function body
- ...

This would be useful for filters to be able to get/put 
such constracts, without needing to go through and try to 
reason where they end, token by token.

I could figure this -eventually- from the Source, but... 
someone will know why yes/no, with reasons.  I do hope it 
can be done, and I do hope token filtering makes it to Lua 
Proper.

-asko