Hi all,

(Élie, I'm going to repeat here mostly what I said in fctt, expanding a bit.)

Elie Roux a écrit :
> I'm the developer of luainputenc (inputenc adapted for LuaTeX). Sorry to
> come back to this topic, but I think an answer to Will's question would
> be necessary soon... inputenc needs adjustments in order to work with
> LuaTeX and XeTeX.

I'm sorry but I disagree on this point. I don't think it is urgent to adjust the
real inputenc. LuaTeX is still in early beta, so it should be used only by
somehow experienced users, or at least users aware of what they are doing. Such
users should be able to understand that they should either encode their source
in utf-8 (and don't load any inputenc) or load luainputenc.

By the way, people using XeTeX just encode their sources in utf-8 and skip
loading inputenc, and seem to be happy with it.

> I can build a new package called luainputenc, but I
> think it will be confusing for the user, and it makes LuaLaTeX unable to
> compile old LaTeX documents,

Ok, so this is the point. You expect LuaTeX to become the default engine some
day, and for this to happen, backwards compatibility will indeed be very
important. But this will not happen before (at least) 2012 (announced date for
the first stable version). So I see no harm in waiting a bit before implementing
backward compatibility solutions.

Moreover, luainputenc, as far as I understand it, is currently not able to
compile correctly 100% of the old documents written for LaTeX over 8-bit TeX,
mainly due to the generated files problem. So IMO it is best to keep it as a
separate package while the issues are not solved. It also needs some (more)
real-life testing before being integrated in inputenc, IMO.

A important point is, people need to know the difference between what is stable
and what isn't. They expect core packages maintained by the LaTeX team to be
stable and work in a 100% compatible way. This expectation should be satisfied.

By the way, while we're at suggesting things concerning inputenc and Unicode TeX
engines, my suggestion would be to detect those engines and issue a meaningfull
error message (not just a warning) like "You're running LuaTeX. inputenc can't
currently work on Unicode variants of TeX such as LuaTeX. Please consult
http://www.tex.ac.uk/cgi-bin/texfaq2html?label=lualatex for how to use LaTeX
with LuaTeX." and refusing to load.

Of course the above message is just a suggestion and we would have to agree with
Robin to maintain FAQ entries for lualatex and xelatex, explaining the
state-of-the art ways of using LaTeX on top of such engines, and giving minimal
preamble examples etc. (Also mentionning fontspec for XeTeX, etc.) The authors
of LaTeX packages related to XeTeX/LuaTeX support should send updates to Robin
every time they do a significant user-visible change in their package.

In short, inputenc on Unicode TeX engines should IMO either just work or just
fail. This it can't just work now (or at least this needs some testing to know),
better make it just fail in a helpful way.

Manuel.