> I've had a brief glance at filters and so on, and they appear to be > intended to work over a block of text ... I could extend the block to > include the whole document, but I don't see that helping ... Probably I > just don't understand them properly :-)
Or else I didn't understand what you were trying to do. My thought was that you'd wrap the whole document up to the part where you want to display the validation mark, but that won't work if you need to pass the entire document (including the very end of it) in order to check its validity. If that won't work, you pretty much have to do two passes. The second pass might be through some incredibly simple regex though (s/valid//), instead of sending it through TT again. That could save you some time and RAM. I'm sure you could hack ttree to do this. - Perrin
