I just found out that the line break command can have a star, which explains why things like ` \begin{array}{c}*\*\\1\\0\end{array}` doesn't show anything in the second column

An "unprotected space" doesn't count as an item (but does count as a token) right?

Also (is there an unmatched open parentheses in paragraph 3 of tl_range documentation?

There are some questions tex.stackexchange.com/questions/516889/… for example for preserving spaces.

@DavidCarlisle I'll remind myself: I think the worry was 'edge case' colour models

@barbarabeeton ooh twitter.com/In_Otter_News2/status/1445814886261534721

Her name is Lua! luaotter with a \vbox ;-)

@Rmano ooh

@MarcelKrüger, @UlrikeFischer l3kernel/l3backend off to CTAN: we now have properly-working DeviceN

@MarcelKrüger Could you add some comments to the .dtx on how the dvips code works - I get the general idea but it's a good idea to collect up these things for the future

\ExplSyntaxOn
\cs_new:Npn \Subs #1 #2 {
	\cs_generate_from_arg_count:NNnn \__subs_aux:w \cs_set:Npn {\tl_count:n {#2}} {#1}
	\cs_set:Nn \__subs_auxi:n {\__subs_aux:w ##1}
	\exp_args:Nx \__subs_auxi:n {#2}
}
\ExplSyntaxOff


\def\a{123}
\def\b{456}
\Subs{\detokenize{#1} and \detokenize{#2}}{
{\a}{\b}
}

Also is there something similar already? People keeps using \expandafter

@JosephWright good ;-)

@PauloCereda -- Otters, even untrained ones, are such fun to watch. They always find a way to have a good time.

@barbarabeeton @PauloCereda Good time like this? ;-) Do Otters Eat Ducks?

@StefanKottwitz -- That's not what I was thinking of. Actually, neither of these linked items is clear about whether the reference is to sea otters or river otters, although the pictures appear to show sea otters. River otters aren't as large, and I suspect would find a full-sized duck to be a serious opponent. Frogs, on the other hand ... it's not easy being green.

@barbarabeeton "it's not easy being green" reminds me of political Twitter in Germany.

I guess on Twitter it's not easy being anything anyway.

@StefanKottwitz -- Undoubtedly true; I haven't followed that closely, and indeed, I'm not a twitterer. But I do have a fondness for Kermit the Frog, and have loved the (preferably unspoiled) outdoors since I was a little kid, and am disgusted with the way many people treat the only home they can ever have. Mother Nature is not happy with us, and with reason.

@barbarabeeton Also I loved Kermit, and being outdoors in the woods as a kid. What can we do with the short-sighted politics? Prepare our kids for the worst.

@barbarabeeton ...agree, and we started very early. Friends of mine are just back from Mesopotamia, which was "the most fertile region on the planet" before we arrived some 10k years ago. The photos are... appalling.