Hello Phelype,

Le Mon, Oct 18, 2021 at 09:56:51AM -0300, Phelype Oleinik a écrit :
> Hi Thierry,
> 
> On Mon, Oct 18, 2021 at 5:23 AM LARONDE Thierry <[log in to unmask]> wrote:
> >
> > ---8<---
> > LaTeX2e <2021-06-01> patch level 1
> > inputing expl3.ltx (l3kernel/expl3.ltx (l3kernel/expl3-code.tex
> > ! !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! !
> > Argh, internal LaTeX3 error!
> >
> > Module kernel, message name "command-already-defined":
> > Arguments '\@@_use_none_delimit_by_q_recursion_stop:w' and '\long
> > macro:#1\q_@@
> > _recursion_stop ->'
> >
> > This is one for The LaTeX3 Project: bailing out.
> > \msg_error:nnxx ...he LaTeX3 Project: bailing out}
> >                                                   \tex_end:D
> > l.2946 ...@_use_none_delimit_by_q_recursion_stop:w
> > --->8---
> 
> That is odd.  It seems that expl3-code.tex is not properly docstripped
> from the sources, because control sequences |\@@_...| should not exist
> in executable code (like expl3-code.tex), only in the sources.  Some
> control sequences across expl3 modules have the same name, except for
> the module name, denoted by the |@@| prefix, which is replaced by the
> actual module name by (l3)docstrip.  Without the replacement you end up
> with multiple control sequences with the same name, and you get the
> error you are seeing.
> 
> Some time ago the |@@| replacement from l3docstrip was merged into the
> main docstrip code, so make sure you are using the right version.
> 

This is probably it. This was docstrip'ed with an "old" version of
docstrip.

> > So is there anywhere (and please: not the >1500 pages "manual"!) short
> > explanations about how to add a new engine? What has to be set and
> > where?
> 
> No.  New engines aren't created every day, so little effort was put into
> that (zero, in terms of documentation).  But from what I've read about
> Prote, it should take more or less the same code paths as XeTeX, except
> where the engine is specifically tested for (in which case, what you
> showed should suffice for the most part of it).

OK. I will try to tackle the chunks in .dtx.

Thanks!
-- 
        Thierry Laronde <tlaronde +AT+ polynum +dot+ com>
                     http://www.kergis.com/
                    http://kertex.kergis.com/
                       http://www.sbfa.fr/
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