@UlrikeFischer I'm sure I recall there was something after a,b but I keep getting stuck...

@DavidCarlisle Wikipedia says it goes back to A again en.wikipedia.org/wiki/ABBA :)

@UlrikeFischer do you have any xetex char class examples? I can now do all class pairs including 4095 boundaries, but as it is working on node iteration not characters, you can't insert unmatched group start/end or font changes, but you can insert characters, spaces color etc. Is that enough to make xxetex usable...

@PhelypeOleinik mamma mia, here we go again

:)

@DavidCarlisle to late to look now, but imho the ctex classes have some, and a few of polyglossia languages.

@DavidCarlisle This in fact, may turn out very suitable for me. How can I learn this \pdfliteral{} thing? I don't seem to be able to search out anything?

@youthdoo it does what it says: passes raw (literal) PDF instructions straight to the output. You’ll want to read the PDF manual

@youthdoo the command is just for pdftex (luatex has similar command), higher level packages like color, graphcs, tikz, ... use \pdfliteral when needed on pdftex and use similar but different constructs elsewhere, so (unlike using \pdfliteral directly) the document remains portable. so \pdfliteral is in the pdftex manual, its content is pdf so the pdf reference manual

@youthdoo there 0 0 m moves to (0, 0) and starts a new path 100 0 l adds a line to (100,0) 100 100 l adds a line to (100,100) then f closes the path with line segment back to the start and fills the path with the current fill color (black by default) so those are the only commands you need for polygons

@DavidCarlisle I agree, hiding \directlua was a dumb idea. The user will most likely want to use luaotfload.

@orthocresol I can do that for you. Note that you really only need the "Single Font" variant for about 81€. tex.stackexchange.com/questions/320636/…

@HenriMenke on balance I agree we shouldn't hide luatex in this case, but we'd load luaotfload in everyjob anyway. The main reason for possibly renaming is not to stop users using it but to make packages doing \ifx\directlua\undefined xetex stuff\else luatex stuff\fi take the xetex path, but unlike the xpdftex case mostly if package has luatex speciific code it should probably use it here. I still have to set up the .ini file for building the format I'll adjust the names at that time.

@DavidCarlisle All sounds good to me

@DavidCarlisle I have a feeling we need some expl3 changes before we can go for making it 'almost normal LuaTeX'

@JosephWright wow, are you an expl3 developer?

@DavidCarlisle :)

@DavidCarlisle Question is for xxetex what exactly should be true: presumably \sys_if_engine_luatex_p: but not \sys_if_engine_xetex_p:?

@JosephWright I wondered about that, same for iftex versions, I'm tempted to say both true

@DavidCarlisle I had a go at making a .ini version, didn't work out ... although I do wonder if that's what's wanted here (as opposed to lualatex \input xxetex.tex

@DavidCarlisle I think that can work, but it will need some checking ...

@DavidCarlisle Presumably that's fine for the 'either or' situations, and for the 'we need a clear answer' we choose LuaTeX?

@JosephWright yes

So \sys_if_engine_luatex:TF { ... } { \sys_if_engine_xetex:TF { ... } { <8-bit> } }

@JosephWright back later:-)

@DavidCarlisle Have a lot of cheese fun

@JosephWright I then want a nice looking decision tree xkcd.com/1619

@JosephWright That used to be the SuSE motto.

Whether it still is, I don't know.

Ohh, so there is now also xxetex. If you add another x it can be a hot version of etex. :)

@mickep another term we don't want to search on the internet?

@Skillmon I guess that could not be worse than latex. :)

@HenriMenke Thanks very much. Here's a MWE (you just need to put in the font commands). Could you use Minion Pro for the text font as well? gist.github.com/yongrenjie/1461dec1ebf16c4f7e9285f21673cc7a - Thanks also for the note about the single font. I was thinking about the basic set myself (I am outside the EU, so it is a tiny bit cheaper, perhaps the only good thing that has resulted from Brexit so far...). But the screenshots in your answer lead me to agree that it's unnecessary.