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Date:         Sat, 1 Jan 2011 20:56:24 +0000
Reply-To: Mailing list for the LaTeX3 project
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From: Joseph Wright <joseph.wright@MORNINGSTAR2.CO.UK>
Subject: Re: LaTeX3 and engines
To: LATEX-L@listserv.uni-heidelberg.de
In-Reply-To:  <20110101204323.GA14218@khaled-laptop>
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Status: R

On 01/01/2011 20:43, Khaled Hosny wrote:
> Just wondering, what benefit pdftex have over luatex (with the later
> being an extension of the former), or is it about people who are not
> willing/can't switch to new engine? Do we expect such people to be
> welling/able to switch to latex3 either?

At present there is not too much of an issue: we don't have any working 
functionality for LaTeX3 where this question really shows up. This may 
change once we have some font stuff. (As I said, I have some ideas in 
this area, which include 'shameless rip-off fontspec'.)

There is quite a large body of stuff which doesn't really need LuaTeX: 
stuff in western European languages using fonts already available to 
TeX. I suspect that forcing this subset of work to drop pdfTeX, which is 
quite capable of doing the job, might be consider a bit 'over the top'.

As I said earlier, we decided to require \pdfstrcmp after some 
applications came up where the alternatives were a bad idea (difference 
in expandability with different supported engines). So this might change 
as we develop more code. I can only comment on what we have now, where 
there is no strong case for dropping support for pdfTeX. (Indeed, almost 
all of the day-to-day testing I do uses pdfTeX as it remains my default 
engine. LuaTeX is a lot slower, I'm afraid, quite apart from questions 
about bugs introduced by the ongoing changes.)
--
Joseph Wright