03:00 - 18:0018:00 - 00:00

3:23 AM
https://www.theverge.com/2018/1/17/16901664/yellow-bellied-marmots-social-lifespan
I am wonder if I should continue chatting....

2 hours later…
5:41 AM
@marmot lol

5:54 AM
@CarLaTeX we don't talk anymore.. :P

@manooooh <3

3 hours later…
8:30 AM
@DavidCarlisle Hi, David, can I ask you for a clarification for calligraphic fonts of mt2pro?
@daleif Good morning to you and good work.

@Sebastiano you can ask, but I don't have the font

@DavidCarlisle Don't worry for the font.
@DavidCarlisle When I want to insert any mathematical character in bold I use the command \boldsymbol. This command does not work if I use the \boldsymbol{\left(} command but it works correctly with \boldsymbol{\Bigl(}.
@DavidCarlisle For curly fonts, which are the calligraphic characters of mt2pro I wanted to get bold. \boldsymbol is ineffective or the command does not work at all, but if I insert the package \usepackage{bm} instead it tells me the .log file that I have declared many fonts. What can I do?

@Sebastiano yes of course, that is nothing to do with \boldsymbol, you would see the same with {\left(} you can't have \left without a matching \right in the same group. But almost always it's better to use \bm than \boldsymbol and actually you can use \bm{\left(} (I thought you were going to ask about \mathcal ?

@StefanKottwitz Good morning to you and happy day.

@Sebastiano Good morning!

8:40 AM
@DavidCarlisle I want to get the calligraphic character in bold, but with \usepackage{bm} it doesn't work. :-(

@Sebastiano try reducing \bmmax (default is 4) to a lower value with \renewcommand or try loading less fonts
@Sebastiano do you want the whole expression bold or just a subterm? (bold brackets in a subterm seems a bit strange)

@DavidCarlisle I didn't know that. My source file is very long and I wouldn't know which package to delete. It seems to me that I need all of them. Right now I'm at school and my students are doing in absolute silence the math test on exponential inequalities and logarithmic calculations. With absolute sincerity they are polite and fantastic. Could you send me a few lines of code please, so I can try it at home if that's okay?

@Sebastiano I just asked if you were making the whole expression bold or just a part of it. If the whole expression is bold then \boldsymbol and \bm are wrong thing to use, you should use \boldmath

@DavidCarlisle Yes is true that bold large brackets are a bit strange. But for me is good. Ah ok. Should I make \boldmath{\mathcal A} for bold curly script?

@Sebastiano no \boldmath goes outside the math \boldmath .... $x$ and $y$ with give bold math italic x and y

8:58 AM
@DavidCarlisle David must be \boldmath$\mathcal A$ inline mode and for an equation, $\boldmath{\mathcal A}$? Is it correct?

@Sebastiano No!!! as I said just now. \boldmath has to be outside the math it is a core latex command see the latex book or any tutorial. \boldmath $\mathcal{A}$ will make a bold A if your fonts have a bold A.

@DavidCarlisle David didn't remember the boldmath command and its use. I hope I didn't make you angry. I send you my warmest greetings and inform you that a user who votes negatively on the answers and questions that I write even if they are discreet I have identified him. Thank you very much.

9:17 AM
Given the fact that MiKTeX is now also cross-platform, working on Windows, Linux, and macOS, is there still any advantage in using TeX Live? Hmm...
Hello @PauloCereda have you finished your thesis finally?

hi all, I have a quick question about the bxpapersize package .....well, errrr....what exactly does this package do?

@JasperLoy rather I wonder why miktex was ported to the non windows versions. The only reason I thought it existed was to be more like a "native windows" application.
3

The README.md says "As is well known, in LaTeX processing layout paper size specified by document class options is not automatically applied to output paper size. "
It wasn't well-known to me at all!

@Krishna it's also not true if you load graphicx, or hyperref, or geometry packages.

Should I be concerned with this package for accurate printing of a Ph.D thesis on a4paper

9:23 AM
@Krishna no

@DavidCarlisle Should I ask in the main site? Seems some historic context here?
As in, if graphicx, hyperref or geometry is not loaded, the documentclass a4paper option won't be applied to the output?
That's the first time in my life I have ever heard of something so bizzarre.... I thought the base classes revert to US letter size unless invoked with the a4paper or other similar modifier options

@Krishna had a quick look at the source and it's mostly extra support for using \mag magnification which is basically only used in japanese setup.
@Krishna define "applied"

@DavidCarlisle Well. the layout on the screen (PDF) must fit exactly as expected on the output paper. I thought the PDF standard defines this precisely. It's confusing when you have such packages claiming things like "As is well known......."

@Krishna The readme also says "It should be noted that there are many pack­ages that try to syn­chro­nize pa­per sizes, ...".

@Krishna classically tex has no notion of external paper size so in pure latex if you go [a4paper] then the text block is set to the right width for A4 and the left and top margins also, but tex has no notion of physical paper size, in 1982 it would print on whatever size paper you had in your printer and that's all there was too it.
@Krishna Once you have loaded a package that has driver-specific knowledge so it knows that it is pdftex or latex+dvips or xetex+xdvipdfmx or whatever you can (and it does) also insert a \special or set \pdfpageheight or \pageheight or whatever is needed for that platform to set the specified physical media to match, that means on-screen previewers can size their windows accordingly

9:39 AM
@DavidCarlisle thank you for the excellent information
Do you think we can rightfully term the bxpapersize package as extraneous/superfluous?

@Krishna as i say (after a full 30 seconds inspection of the code) it looks like it is extra features mostly of use for japanese (ptex) tex.

@DavidCarlisle cool. Thank you for your help. Much appreciate these pointers.

@Krishna well unlike geometry it doesn't change other page values, and if you don't want to load graphicx or hyperref it is an alternative.

@UlrikeFischer and @DavidCarlisle are you both saying that for e.g. if I have a simple letter using the base letter class without any geometry, graphics or hyperref packages, the printed output won't be as expected?
That's a rather profound statement, no?

@Krishna the printed output will depend on your printer driver. The pdf-size can be unexpected - that depends on the default of your tex system. My default is A4 and so this shows different values:
\documentclass{letter}
\begin{document}
paperwidth: \the\paperwidth

pdfpagewidth: \the\pdfpagewidth
\end{document}
@DavidCarlisle Hans made just an interesting claim about how font design sizes and t-shirt-sizes are connected: "so given that when picking up a conference t-shirts at bachotex you have to get one size smaller than you expect, one can also assume that the gyre collection designsize is somewhat oversized"

9:50 AM
@UlrikeFischer That's unbelievable.
paperwidth: 614.295pt
pdfpagewidth: 597.50787pt

@Krishna But @DavidCarlisle just tried to explain this to you. Don't say you don't believe him.

@UlrikeFischer "the printed output will depend on your printer driver." Can you please explain this a bit more?
Well...unbelievable as an idomatic expression. I believed and understood what he said..... But seeing it in typeset output reinforced it
So, it's a good practice to load at least one of these packages bxpapersize, hyperref, graphicx, geometry in all documents

@Krishna If you have an a4 paper pdf and sent it to a printer which uses letter formats, the printer driver will have to decide if to scale the pdf, or to refuse to print it, or to cut out some margins.

@UlrikeFischer Understood

@Krishna Or to use a KOMA-class or memoir, which set the size too. Normally today I don't worry about, someone always takes care of it.

9:55 AM
@UlrikeFischer journals frown upon Koma-class or memoir
It's okay for a thesis

@Krishna the printed output will be as I expect, I can't speak for other people's expectations. (In my case it will be the same as if I add geometry)

@UlrikeFischer yes, seems like elsarticle does.... But asme does not .... took a quick look at my old submissions

10:33 AM
@DavidCarlisle Thank you very much forever. I hope you're not angry with me.
@UlrikeFischer Hi, and good morning.
Good morning everybody to all users.

@KhaledHosny hi, don't see you here so often these days:-)

Ooh, hi @KhaledHosny

@DavidCarlisle was in the hate phase of my love-hate relationship with TeX.
Hi all

@KhaledHosny Happens to all of us ;)

@KhaledHosny hello!
@Sebastiano good morning to you too.

10:47 AM
@KhaledHosny aren't we all!
@JosephWright dungeon again I see:-)

@DavidCarlisle Oh yes :)

Any idea if it will ever be possible to use FFI with LuaTeX without --shell-escape?

@JosephWright and pizza?

@UlrikeFischer That's the plan

@KhaledHosny I was hoping to smuggle harfbuzz in that way:-)

11:00 AM
@DavidCarlisle me too, but if it will require --shell-escape then that is a big hindrance.

yes, Hans and Luigi have a paper where they say this: which does't sound too good.... First some words on the checks. As it is now,
ffi is enabled if and only if --shell-escape is
true and --shell-restricted is false (the cnf
files are also considered) because ffi is inherently
insecure (as we will discuss in greater detail later).
@KhaledHosny now if there was anyone around who understood harbuzz and tex, perhaps a version of luatex that had harfbuzz permanently linked rather than loaded via ffi could be made......

@DavidCarlisle may be we can have some safe libraries like there are safe executables allowed even without --shell-escape? Just thinking out loud…
@DavidCarlisle I wouldn’t mind doing that, but w would be effectively forking LuaTeX, not something I’d want to be responsible for.

@KhaledHosny that occurred to me as well, but not knowing the details of the ffi interface I didn't want to suggest it (actually I failed to get FFI to work with my normal cygwin setup so I gave up looking) but that was some months ago, the luatex sources have changed a lot since, so I should try again....
@KhaledHosny yes that is the issue, but if it could be arranged that it was a gentle extension that could just pull in the luatex sources and change the build scripts to add a harfbuzz library it might be something to consider....

@DavidCarlisle Alternatively, if someone can convince Hans and co to bundle a HarfBuzz Library with LuaTeX, that is otherwise unused and does not get in the way with their fonts adventure, we can then build on top of that. Not volunteering to be the one convincing them, though.

@JosephWright can I nominate someone? :)

11:08 AM
@PauloCereda Yes, of course, provided they agree: email preferred

'ello, Psmith is now fully operational.

@KhaledHosny I think people have tried. It's difficult to sound convincing though if the only script you can read is ascii English text so hard to speak with any authority on the relative merits of harfbuzz and the lua font loader:-)

@JosephWright ooh /evil thoughts

@DavidCarlisle It just occured to me that it can be a light luahbtex fork à la luajittex, that might work. Need to check how luajitex sources are set up.

@JosephWright they won't. :)
/duck

11:09 AM

bah that's cheating

@KhaledHosny sounds good to me!

@KhaledHosny You are preaching to the choir here :) @DavidCarlisle and I would love to see a HarfBuzz-equipped LuaTeX - it would almost certainly make the XeTeX vs LuaTeX question obsolete. But Hans doesn't see that ...

Now trying to find a public LuaTeX source repository that is not behind a login page…

@KhaledHosny GitHub mirror ...

11:14 AM
@JosephWright I know :)

@KhaledHosny github.com/speedata/LuaTeX perhaps

?
Both seem to be in sync

@KhaledHosny yes this one (although the speedata one is also in sync )

@KhaledHosny True: the TL one is just bigger ...

@JosephWright that isn't texlive it's Luigi's git mirror just of luatex

11:17 AM
@DavidCarlisle Ah, right

@KhaledHosny there is also github.com/TeX-Live/texlive-source which is the full texlive sources mirrored to github
@KhaledHosny luatex in there is usually slightly behind the luatex-specific repo of course.

@DavidCarlisle and it has github.com/TeX-Live/luatex as well, I guess that one is more “official”

@KhaledHosny That's the version Hans and Luigi have decided is stable enough to push to texlive, yes.

@DavidCarlisle should be good enough.

@KhaledHosny @DavidCarlisle well I would be willing to try again, but as David said it would be good to have some more concrete problems. Currently I only know something about a burmese problem and few small glitches in Devanagari.

11:26 AM
@UlrikeFischer I don’t know what scripts the font loader currently supports, does it support the new Universal Shaping Engine docs.microsoft.com/en-us/typography/script-development/use? HarfBuzz currently has 7 script-specific shaping engines, some support more than one script.
@UlrikeFischer Arabic, Hangul, Hebrew, Indic, Khmer, Myanmar, Thai and USE

11:45 AM
@KhaledHosny Well I need concrete examples which compare good (xelatex) with bad (current context if possible or lualatex) output. Can you add some to tex.stackexchange.com/questions/454031/…?

/duck

/say
@PauloCereda still not activated? :(
/duck

/borussia

11:58 AM

@Skillmon Let me bring it back for you. Hold on.
/shutdown

Initiating shutdown sequence. Cheerio!

@PauloCereda I like him a lot :)

@Skillmon <3

@PauloCereda yesterday was the first time I actually met him in chat :)

12:00 PM
@Skillmon ooh

'ello, Psmith is now fully operational.

/say

Master Maloney eyed the cat's reserve, and was full

/say

I've reason to know he's got in de street sickin' a dawg on to a local paper of the highest possible level of domesticity

12:01 PM
@PauloCereda Can we train him stuff?

@Skillmon That's the plan. The training set is from a book, but my original idea is to make him construct sentences based on our own messages. Sadly, it takes a lot of time to start creating stuff. :)

@PauloCereda like: /train love "Skillmon loves me!" and then he is saying "Skillmon loves me" every time I use /love.

I can reset the sentences and let him learn only from our sentences, that's ok. :)

@UlrikeFischer Will see if I can make some examples.

@Skillmon This is /learn
/learn love Skillmon loves me!

12:03 PM
@PauloCereda Saved.

@PauloCereda ah, makes sense.
/love

Skillmon loves me!

/love

:) <3

/say

12:05 PM
Won't you clear your gang of German comedians away, and give her a letter, quite a pleasant letter, you understand, pointing out the necessity of being used for sleeping purposes at night

WAT

@DavidCarlisle Saved.

/pancake

12:06 PM
Hmmmm
Jun 29 '17 at 16:15, by Paulo Cereda
@DavidCarlisle you are not mean :)
@PauloCereda ^^

You are... oh wait
/say

<div class="onebox ob-message"><a rel="noopener noreferrer" class="roomname" href="/transcript/message/38455530#38455530"><span title="2017-06-29 16:15</span></a>, by <span class="user-name">Paulo Cereda</span> <br/><div class="onebox ob-message"><a rel="noopener noreferrer" class="roomname" href="/transcript/message/38455530#38455530"><span title="2017-06-29 16:15:06Z">Jun 29 '17 at 16:15:06Z">Jun 29 '17 at 16:15</span></a>, by <span class="user-name">Paulo Cereda</span> <br/><div class="quote"

@PauloCereda You are... too slow

hahahahahaha
@DavidCarlisle :)

@Psmith I like your confidence that we all can render on the fly html in your heads :)

12:14 PM
@samcarter 'ello, I bid you good day! Type /help to see all my commands.

@KhaledHosny Thanks. And no need to hurry, I don't have much time this and the next week anyway.

12:32 PM
/juventus
/help

'ello, I am Psmith, the TeX bot!

List of commands:
/8ball     Simulates a magic 8-ball.
/cricket   Fetches cricket news from ESPN.
/duck      Displays a random duck picture.
/football  Fetches football news from ESPN.
/help      Displays this help message.
/learn     Teaches the bot a new command.
/roll      Rolls a variable-sided die or makes a choice.
/say       Makes the bot say something.
/shutdown  Terminates the bot (admins only).
/tag       Displays the description of a TeX.sx tag.

@PauloCereda We need to teach Psmith some new teams!

12:49 PM
@egreg he already knows the best one.
/tikzling

/llamas

/learn juventus

@UlrikeFischer Deeply sorry, old chap, but you haven't specified the command output.

12:55 PM

@UlrikeFischer Saved.

/juventus

@egreg ^^^^

@CarLaTeX in fact I feel </3 (and you are not to blame) xD

1:03 PM
@egreg hold on. :)
/shutdown

Initiating shutdown sequence. Cheerio!
'ello, Psmith is now fully operational.

/football juventus

- Real Madrid's Luka Modric: Cristiano Ronaldo, Zinedine Zidane exits 'surprising'
- Cristiano Jr scores a brace for Juventus under 9's.
- Cristiano Ronaldo shares video of son scoring two goals for Juventus under-9s
- Manchester United's Romelu Lukaku hints at Serie A move, praises Juventus
- Portuguese newspaper defends Cristiano Ronaldo Real Madrid settlement allegation
- Real Madrid sue Portuguese newspaper over Cristiano Ronaldo rape allegations
- Cristiano Ronaldo lawyer acknowledges Kathryn Mayorga agreement

@egreg ^^
/shutdown

Initiating shutdown sequence. Cheerio!
'ello, Psmith is now fully operational.

1:11 PM
/say

Nevertheless, the crisis was at work on a ten weeks

- ICYMI: Sanchez caps Man United comeback, unreal Mbappe & more
- Bayern thrashed at home as pressure mounts
- Bayern Munich shut out at home in loss to Borussia Monchengladbach
- Kovac insists spirits are high at Bayern despite poor form
- U.S. team veterans John Brooks, Fabian Johnson score in Bundeliga action
- Southampton 0-3 Borussia Monchengladbach: Saints outclassed
- Southampton sign Denmark defender Jannik Vestergaard from Borussia Monchengladbach
- Denmark defender Jannik Vestergaard to have Southampton medical -- sources

@UlrikeFischer ^^

@PauloCereda ;-) "Bayern thrashed at home as pressure mounts " is quite nice ;-).

1:14 PM
@UlrikeFischer ooh
/duck

@PauloCereda didn't you know? They won 0-3 against Bayern last week. The town was quite happy...

@UlrikeFischer yay

1:30 PM
@manooooh it's not my fault, lol

1:40 PM
/8ball is it @CarLaTeX's fault?

Jan 9 '13 at 10:36, by Paulo Cereda
Stupid bot.

How could one create a macro such that \Rectangle{4}{<text>} would print a block of rectangular shape? I used something idiomatic like \newcommand\Rectangle[2]{\begingroup\setbox0\hbox{#2}\begin{minipage}{\dimexpr\‌​wd0/#1\relax}#2\end{minipage}\endgroup}, but this doesn't get it quite right. (the aim is to get the last line ending also at the right margin of the block)
/8ball is it @CarLaTeX's fault?

@Skillmon Don't count on it

/love

1:44 PM
Skillmon loves me!

@Skillmon \parfillskip=0pt

@DavidCarlisle thank you very much!

@Skillmon I'm more help than @Psmith

@DavidCarlisle 'ello, I bid you good day! Type /help to see all my commands.

1:50 PM
see ^^

oh he's not listening to you:-)

@DavidCarlisle apparanlty, @Psmith is just busy at this moment looking for new ducks.

@Skillmon 'ello, I bid you good day! Type /help to see all my commands.

2:13 PM
/say

@CarLaTeX hehe

A tentative cough, suggesting that the money

/help

'ello, I am Psmith, the TeX bot!

List of commands:
/8ball     Simulates a magic 8-ball.
/cricket   Fetches cricket news from ESPN.
/duck      Displays a random duck picture.
/football  Fetches football news from ESPN.
/help      Displays this help message.
/learn     Teaches the bot a new command.
/roll      Rolls a variable-sided die or makes a choice.
/say       Makes the bot say something.
/shutdown  Terminates the bot (admins only).
/tag       Displays the description of a TeX.sx tag.

Wow
/8ball

2:15 PM
@manooooh Yes definitely

@Psmith why did you say this?

@Skillmon 'ello, I bid you good day! Type /help to see all my commands.

:)

Omg is he typing so fast or is he a real bot?

/say

2:18 PM
I anticipated that on my return the cry, 'more scope!' I must look into this matter

/8ball are you a real bot?

@UlrikeFischer Without a doubt

@Psmith do you have the ability to give stars to comments?

@manooooh 'ello, I bid you good day! Type /help to see all my commands.

@manooooh see ^^^^

2:20 PM
@UlrikeFischer I can't see a command for that. Maybe using "about" command?
Someday it will be the day that we won't talk anymore but with bots

/shutdown

Initiating shutdown sequence. Cheerio!
'ello, Psmith is now fully operational.

/8ball

@PauloCereda My dear chap, you need to ask me something!

/8ball Is David mean?

2:29 PM
@PauloCereda My sources say no.

Oh no
/say

I may borrow the expression of their offspring, and which bristles with little stories about the visitor, who seated himself upon a more delicate phase

/8ball Is David mean?

@Skillmon Fo' shizzle.

/8ball is Paulo mean?

2:33 PM
@manooooh Outlook not so good.

Hahahaha
/8ball is manooooh mean?

@manooooh Fo' shizzle.

<3?

Psmith, the TeX bot by Paulo | Inspired by OakBot by Michael | source code | JAR built on: Today at 17:00 | started up: 9 minutes ago | responded to 113 commands since out 15, 2018

Is he operative since yesterday? I thought it was a few days before

2:43 PM
@manooooh I am improving the code.
/8ball do you like @Skillmon?

@PauloCereda Outlook not so good.

oh no
/love

Skillmon loves me!

/say

His beaming smile will be a success! What the bullet came through the open door

3:03 PM
/shutdown

Initiating shutdown sequence. Cheerio!
'ello, Psmith is now fully operational.

/battle

Battle for today: egreg 230 vs. 65 David. So far, egreg is winning.

@egreg, @DavidCarlisle ^^
/say

You understand the general average aspect of these, on the table on which I think

3:07 PM
/help

'ello, I am Psmith, the TeX bot!

List of commands:
/8ball     Simulates a magic 8-ball.
/battle    Displays the battle of titans!
/cricket   Fetches cricket news from ESPN.
/duck      Displays a random duck picture.
/football  Fetches football news from ESPN.
/help      Displays this help message.
/learn     Teaches the bot a new command.
/roll      Rolls a variable-sided die or makes a choice.
/say       Makes the bot say something.
/shutdown  Terminates the bot (admins only).

/battle

Battle for today: egreg 230 vs. 65 David. So far, egreg is winning.

@DavidCarlisle ^^

/duck

3:10 PM

awwww
@barbarabeeton, @AlanMunn ^^ :)

/duck

/say

Not a word was spoken as he carefully dusted that piece of meat in order to snare crocodiles

3:13 PM
This duck looks worried!
WAT

@PauloCereda Is it me or Psmith's sentences are improving?

@PhelypeOleinik it's you, he is an idiot. :)
/say

You understand the general average aspect of these, on the table on which I think

@PauloCereda Takes one idiot to think the other is saying meaningful stuff :P

@PhelypeOleinik oh no
/8ball are we idiots?

3:16 PM
@PauloCereda Uh-huh.

/roll cake pie icecream

@PauloCereda icecream

ooh

Is there a neat expandable way to check whether something is a valid skip or length expression? Unexpandable could be \begingroup\setbox0\hbox{\skip0=#1pt}\ifdim\wd0>0pt\endgroup<true>\else\endgrou‌​p<false>\fi. But I can't think of a neat expandable way :(

3:23 PM
/say

And what more could you have the ability to give him audience, Comrade Windsor

@Skillmon look at \@defaultunits for a simpler way of doing that, although still not expandable as it uses \afterassignment

@DavidCarlisle how does \afterassignment\remove@to@nnil help me? Perhaps I'm stupid at the moment but all it does is eat the remaining pt in \skip0=#1pt if #1 is a valid skip, how should I test if #1 was a skip then?

@Skillmon perhaps \pdfstrcmp{\the\dimexpr 0pt+(#1)-(#1)\relax}{0pt} ?
@Skillmon use same thing but replacing \remove@to@nnil by a version that checks if the thing it is removing is empty

@DavidCarlisle yeah, thought of that after writing the above, but then your second message appeared and I was busy :)

3:35 PM
@Skillmon doesn't this give an error if #1 is not a number or length?

@DavidCarlisle yes, it should if it is neither of the two... Haven't thought of that :)

@Skillmon oh that makes it easier then, the  0pt+(#1)-(#1) above is designed to accept foobar (and give false)

@DavidCarlisle the \pdfstrcmp must use 0.0pt as second argument, as \dimexpr returns at least one decimal place.

@Skillmon what are you going to do if it's a number not a length? perhaps \@defaultunits does what you need anyway.
@Skillmon details:-)

@DavidCarlisle the \pdfstrcmp method throws ! Missing number, treated as zero. if used with h as argument :(
@DavidCarlisle I just want to decide whether something is valid input (either a number or a length/skip)
@DavidCarlisle the \pdfstrcmp method breaks :( it detects a length and in every other case throws errors.

3:41 PM
@Skillmon oh same as yours then:-) still there may be some dimexpr that you can juggle that works, basically using the fact that \dimexpr normally quietly stops once it has found a length/

@DavidCarlisle but \dimexpr0pt+5-5\relax throws errors.

@Skillmon yes but...

@DavidCarlisle mine works reliable at least for the decision number/length (though breaks if the input is no number)

@Skillmon do you only need to check for an explicit length like 12pt or also for things like \textheight accepting both forms is harder as if you know there are digits then essentially \dimexpr0#1\relax=#1 as 05pt=5pt, but if you need to accept registers then 0\textheight isn't \textheight and it gets more complicated.

@DavidCarlisle the latter :(
@DavidCarlisle how should \dimexpr0#1\relax=#1 work for input like 5? It'd throw errors again.

3:48 PM
@Skillmon I don't think so \hbox{\skip0=#1pt} if #1=0 you get pt in the box and you get exactly the same if #1 is \textwidth

@DavidCarlisle nope. It'd work out.

@Skillmon I don't see how:-)

@DavidCarlisle remember I want to decide whether something is a length/skip or a number.
@DavidCarlisle \skip0=0pt is valid, resulting in a \hbox of 0pt width. So I can tell that it's a number but no length.

@Skillmon do you mean length=yes number=no anything else error, or do you mean number-or-length=yes anything else = no ?

@DavidCarlisle the former
@DavidCarlisle best'd be length=yes, number=no, anything else could be handled, but that'd be a nice extra.

3:51 PM
@Skillmon so given that the number 0 and length \textwidth give the same \hbox in your test, how do you distinguish?

@DavidCarlisle they don't.
@DavidCarlisle \hbox{\skip0=\textwidth pt} is the same as \hbox{pt} and therefore has a width.

@Skillmon that's because I wasn't typing what was in my head:-)

@DavidCarlisle I have to leave now. Maybe I'm back here later.

4:09 PM
@DavidCarlisle back for a while (measuring in minutes)
@DavidCarlisle Please note that the test doesn't have to be expandable, that would have been a nice gimmick (I thought of it as a challenge). So what I have atm should be fine.

@Skillmon What we need here is Bruno ...
@DavidCarlisle So, coming to the dungeon?

4:32 PM
/duck

4:44 PM
@JosephWright thought the same :)
@DavidCarlisle I don't get the \afterassignment variant to work :(

@DavidCarlisle, @egreg, @UlrikeFischer Nearly sorted the error message business

@DavidCarlisle I can make it for a right delimiter like \relax, but if I use some undefined control word like e.g. \endifLenTF@inner I get an undefined control sequence error :(
@DavidCarlisle stupid parsing rules for \skip to not stop expanding after a space :(

/duck

@JosephWright I would like to virtually attend

4:53 PM
@PauloCereda how does @Psmith find the duck pictures?

@Skillmon 'ello, I bid you good day! Type /help to see all my commands.

@PauloCereda Noted
@PauloCereda I'll sort that, then

@Skillmon It's a duck api

@PauloCereda An arara talk?

@JosephWright Oh no worries. :)
/help duck

4:53 PM
duck:
Displays a random duck picture. Images from the random-d.uk website.

@Skillmon ^^

@PauloCereda With it being a TUG year for me, I'll be reusing my talks or something similar: I'd suggest that
@PauloCereda Waiting of course to see which other team members will be there ...

@JosephWright Although you are very productive. :) Having coffee at 6AM and already coding. :)

Is there no \skipexpr defined?

@Skillmon Of course there is

5:03 PM
! Undefined control sequence.
l.56 \skipexpr
5pt+5pt

@Skillmon It's called \glueexpr :)

@JosephWright who did that naming :(

@Skillmon NTS, I guess

@JosephWright I see no choice for me but to use a custom LaTeX format which does \let\skipexpr\glueexpr.

@Skillmon :)

5:13 PM
/duck

@Skillmon There is a handy interface to these things ...

5:45 PM
/duck

03:00 - 18:0018:00 - 00:00