[antlr-interest] Can tree rewriting be done (easily/out-of-the-box) with the current ANTLR 3.x?

[Terence Parr]

Hi Harald,

I apologize for the delay in getting the tree rewriting done.  I am  
back working on antlr now, well after I grade my final exam, but Kay  
Roepke is here for two weeksfrom Hamburg and we will be doing a lot of  
hacking.

In the meantime, you can do tree rewriting by returning a new tree  
from every rule.  Start by including an @after action I think that  
makes a duplicate of the incoming tree $rule.start. When you need to  
do a rewrite, you will have to probably manually build the new tree  
for those productions needing a new tree.  Set the return value.  Ack,  
every reference to a rule will need to build up a new tree based upon  
what is returned.  This will be very messy and error prone.  Hmm...

Ter