Thanks. To figure out what's damaged, it seems like you have to do a diff somewhere? It sounds like this is done at the character level rather than the token level?
No diff, just do the re-lex and damage the tree on the boundaries of where the user typed. My techniques (also, see glitch) usually just assume change has happened since the reprocessing is incremental anyways and won't cascade if nothing has really changed (when reprocessing a tree, the parent is damaged if the end token changed, I guess you could call that a diff).
