Patrick Gundlach <[email protected]> a écrit: > I keep asking myself what are use cases of the token library? The manual > states: > > "These functions are most useful when combined with the token_filter > callback, ..." > > but what are practical applications?
I gave an example in TUGboat paper (https://www.tug.org/members/TUGboat/tb32-1/tb100isambert.pdf), but it wasn't very good (Ulrike Fischer incidentally gave a much better solution in a message to this list; I say ``incidentally'' because she wasn't discussing my paper at all). Also, Taco faked XeTeX intercharstuff with the callback on the wiki (http://wiki.luatex.org/index.php/Token_filter); the problem here of course is that intercharstuff aren't very interesting in LuaTeX. My position is that applications might be close to nonexistent, but it would be a shame if the callback and functions didn't exist! As I see it, the problem is that it's unlikely you always want something in the callback, so if you're using it you're going to keep registering/unregistering a function in it and it looks quite clumsy. Perhaps an area where it may be useful, though, is to peek at the next token(s) without setting their catcodes; I'm not sure there are many applications for that, mind you. Best, Paul
