T T wrote:
> On 10 February 2010 23:46, Will Robertson <[log in to unmask]> wrote:
>>
>> LaTeX3 and LuaTeX are orthogonal; one does not deprecate the other. Certain aspects of the work the LaTeX3 project have done, such as the expl3 macro language, might become less useful when/if LuaTeX is the *only* widely used TeX engine. But until then LaTeX3 will not assume the presence of a Lua programming environment.
> 
> I think that's the wrong way to look at it. The right question to ask
> is how many people willing to switch to LaTeX3 will be at the same
> time unwilling to use LuaTeX. Depending on the answer, sticking with
> eTeX as a base is either a wise decision or useless restriction.

At least I will definitely change to LuaTeX and was really looking
forward to use a combination of LuaTeX+LaTeX3 for programming. From my
point of view (i.e. a quite ”normal“ user) it seems useless to have
LaTeX3 as a powerfull format but sticking with old machines. As
mentioned, backward compatibility is no criterium as it will be lost anyway.

>> LuaTeX will not be backwards compatible with pdfTeX in the generated output (i.e., two identical documents may have slightly different hyphenation/justification choices and therefore different page breaks). While the changes will obviously be rather small, I don't think anyone can really predict when pdfTeX will stop being used.

It will not be used anymore if there is a more comfortable, maybe
faster, and at all ”better“ engine. LuaTeX seems to be this (not faster,
but the rest …) so I am using LuaTeX already for production of (small)
documents. It’s annoying however that I have to load packages to use it
(fontspec etc.) – it would be great to have this implemented in the
kernel which is only possible by fully setting on luaTeX.

> In practical terms there will be some sort of latex3[.exe] program
> provided by TeX distributions to compile documents in LaTeX3 format.
> It might as well point to LuaTeX engine and no one will know any
> better.

That would be the best thing. Maybe similar to the story about naming
the programs (pdf)lualatex and lualatex instead of (pdf)lualatex which
is much more intuitive as dvi is kind of deprecated. Any user new to
LaTeX will be totally confused: 2ε with pdfTeX, LuaTeX or XeTeX, dvi or
pdf output, 3 with pdfTeX, LuaTeX or XeTeX (again, div oder pdf?) while
none of them seem to be really integrated … it would be great to tell
newbies: Just say latex3 to your system and you get a great pdf output
with high quality typesetting.

cheers,
Arno