[XeTeX] Auto Font and Language Package in XeTeX

[Michiel Kamermans]

> I long had that on my todo list, but I'm yet to figure out a proper user
> interface for it; one needs to take care of different font styles,
> optical sizes etc. e.g. English ARABIC {\it english ARABIC} should work
> and get the Arabic text assigned the proper italic font and so on.
>
> The code at lua end is quit trivial, once the script->font mapping is
> defined which is actually the tricky part.
>    

Hmm... that sounds much more narrow than what you can do with XeTeX's 
intercharclass behaviour, and much more like just font-switching. I 
would imagine that something like what XeTeX offers makes it much easier 
to say "if arabic character from non arabic, RTL and font switch (and 
whatever else is requested by the user)". But perhaps LuaTeX wants to do 
these two things separately, which would of course be equally fine, just 
requiring a different approach in terms of packageness

- Mike