TeX, LaTeX and Friends

12:00 AM

When I paste it, I get "picPuerta1.Image = Image.FromFile(My.Application.Info.DirectoryPath & "\sheep." in a line, and "png")" in another line

Is it possible to paste it on a single line?

David Carlisle

@manooooh it's probably pdf-reader dependent but in principle I think you could specify an actualtext string of a space for the linebreak (@UlrikeFischer knows more about that though)

manooooh

@DavidCarlisle as difficult as improving LaTeX :)

@DavidCarlisle I don't understand what "actualtext string of a space for the linebreak" mean

marmot

@manooooh On my Mac I do not have this problem when copying stuff from a pdf file but as @DavidCarlisle is saying this may only depend on the viewer, not on the OS.

manooooh

@marmot oh, thanks. Huh, so I hate my pdf viewer :/

David Carlisle

@manooooh pdf allows (in principle) for you to have hidden data (like alt text in an html image) so that you see something in screen but it cuts and pastes as something else (but it is a typically arcane and tricky thing to set up, search the site for some examples)

manooooh

12:05 AM

@DavidCarlisle ohh, like tabulating code?

marmot

@manooooh And I hate windows. Even though I was using the precisely same viewer on windows as in my tests on my Mac, acroread, during the presentation my nice beamer animation wouldn't work. And it is sort of random, some work, some don't.

David Carlisle

@marmot you should have used picture mode, not tikz

marmot

@DavidCarlisle I am afraid this is not the reason. I was using the animate command in beamer.

manooooh

@marmot yes, you had that problem. Windows is not good for some things... But here, my problem is that I want to share my document, so my thoughts are, as my code doesn't work in my machine, then it doesn't work in any machine, and I'm wrong, as you note

manooooh

12:19 AM

Does someone know how to find the default style code of VB.NET 2010 to replicate on listings?

David Carlisle

@manooooh minted is likely to be closer, it has a vb.net lexer here pygments.org/docs/lexers/#pygments.lexers.dotnet.VbNetLexer

manooooh

@DavidCarlisle thanks for the search!! However: 1) I have never used minted, 2) I don't understand what does lexer mean, 3) I don't know how to implement that link in LaTeX. But thanks!

David Carlisle

@manooooh just use \inpputminted instead of the listings versions, that page tells you the language options you can use vbnet` in this case, you don't need anything else (you need --shell-escape and the python pygments module installed though)

barbara beeton

12:53 AM

@marmot -- You're a mac user. Maybe you can help with this question: tex.stackexchange.com/q/494883

marmot

@barbarabeeton I already tried my luck but this has only lead to an update but not a solution. (I wiped out the mess brew did on my Mac and just downloaded MacTeX and run the installer, that works fine.)

barbara beeton

@marmot -- I kind of figured that MacTeX would be a good recommendation, but since all my relevant texing has been done on a unix box, I'm not inclined to jump in.

marmot

@barbarabeeton Well, there seems to be an updvoted accepted answer that uses brew so for some it seems to work and I do not want to make strong statements.

barbara beeton

@marmot -- Okay. (I hadn't actually read the linked question carefully before I pinged you. Sorry for the noise.)

marmot

@barbarabeeton No, that's perfectly fine. How would you know I am not using brew? As a matter of fact I did use it (without being aware) until @DavidCarlisle and @egreg helped me at tex.stackexchange.com/q/408421/121799 .

@barbarabeeton OK, it was MacPorts, never mind. ;-)

manooooh

1:07 AM

@marmot lol, I just read that in this comment :)

marmot

@manooooh Yes. His " Argh!" is incorrect. It must be "Arrrrrrrrrrrrrrrrrrgh!". ;-)

manooooh

Hahaha

Alan Munn

1:51 AM

@marmot I think Homebrew is better than MacPorts which always caused path problems. And I think Homebrew just runs the MacTeX installer anyway.

marmot

@AlanMunn I see. Good that I didn't try to answer. ;-)

manooooh

I have noticed that the width of the background text of the following section is a bit shorter:

Faheem Mitha

8:22 AM

@marmot Apparently you aren't using the TeX Live local install which everyone around here recommends.

Harald Hanche-Olsen

8:47 AM

@DavidCarlisle what has the latin alphabet done for us?

Faheem Mitha

@HaraldHanche-Olsen It was bought to us by those fine people, the Romans.

Skillmon

11:55 AM

@FaheemMitha good, except for the aqueduct, the streets, and the script, what have the Romans ever done for us?

Monty Python What have the romans ever done for us (Nl subs)

►

Harald Hanche-Olsen

@Skillmon Uh, Times Roman?

David Carlisle

2:32 PM

max_print_line=1000
error_line=254
half_error_line=238

testsuppdir  =  "testfiles/support"
checksuppfiles = {"texmf.cnf"}

@UlrikeFischer (@JosephWright) if the testfiles/support directory contains the settings above and build.lua references them as shown, should that be enough or do I also need to set TEXMFCNF environment variable? the l3build doc seems to imply I should set the environment, but I'd rather do it in Lua?

a local texmf should just work I think without setting the environment, we are doing TEXMFCNF=. (doc misleading:-) hmm so why isn't it working....

Ulrike Fischer

@DavidCarlisle there is a texmf.cnf in testfiles-luatex/support and it works (as I got failures from it ...). But I'm not sure if you can set max_print_line there, doesn't l3build overwrite this again?

David Carlisle

@UlrikeFischer ah maybe that's what it is let me check l3build sources again:-)

@UlrikeFischer `l3build-check.lua: os_setenv .. " max_print_line=" .. maxprintline
`

Ulrike Fischer

@DavidCarlisle I tried just to activate harftex in the luaotfload tests and got lots of failures because of different line length, so I'm quite interested to know if you find something.

Alan Munn

\documentclass{book}
\usepackage[showframe]{geometry}
\usepackage{titlesec}
\titleformat{\chapter}[hang]
{\normalfont\Large\bfseries}{\chaptertitlename\ \thechapter:}{1em}{}
\titlespacing*{\chapter}{0pt}{0pt}{0pt}
\begin{document}
\chapter{A chapter}
\section{A section}
\end{document}

Why do I need to give a negative value for the before sep to get the title to line up with the top of the page?

David Carlisle

@UlrikeFischer having grepped the source I find maxprintline documented in the l3build manual:-) Let me try that...

marmot

3:08 PM

@FaheemMitha Now I do, I think. Back then I didn't.

Ulrike Fischer

@AlanMunn the chapter starts with a \vspace*{}, which is placed a topskip, and then the text is below it.

Alan Munn

@UlrikeFischer I see. Ok thanks.

Faheem Mitha

3:23 PM

@Skillmon They taught us to be afraid?

@marmot I see.

David Carlisle

@UlrikeFischer adding maxprintline=200 to build.lua makes line break changes in several tlg, but hopefully it would be the same for everyone, I could update the files here then see if they pass for you?

Faheem Mitha

People keep telling me I should be using it.

David Carlisle

@FaheemMitha "it" = upstream texlive?

Faheem Mitha

@DavidCarlisle Correct. Upstream TeX Live.

Sebastiano

Hi to everyone

Ulrike Fischer

3:26 PM

@DavidCarlisle fine with me. Say when you uploaded.

Sebastiano

@egreg I'd like some advice on state exams. I am an external member of Mathematics and Physics :-(

user280247

Hi guys!

Sebastiano

@santimirandarp Welcome guy :-)

David Carlisle

@FaheemMitha 99% of people are fine without it (especially if they use pdftex or xetex) but if you use luatex best to be as new as possible as it had far more changes, and if on this site you are quite likely to get answers using the latest versions. if texlive 2017 is fine for you then there is no problem but if you ask about a problem that was fixed in 2018 then "get a newer tex distribution" is a reasonable answer

@UlrikeFischer OK I just need to check that the diffs are all of that form....

Faheem Mitha

@DavidCarlisle I try to stay up to date. By backporting Debian packages if necessary.

Is LuaTeX still changing fast?

David Carlisle

3:28 PM

@FaheemMitha no it is frozen, development team moved on ....

user280247

I've seen gif to file post. But pdflatex outputs that movie15 package is obsolete and should be replaced by media 9

user280247

i've been reading the package to insert my gif file with:

user280247

\includemedia[height=3cm, width=0.6\linewidth]{ }{ani.gif}

user280247

is this wrong (the image file just isnt showed)? Maybe anyone can write a new, updated answer?

user280247

sorry gif to file should be read 'gif in tex file'

Faheem Mitha

3:39 PM

@DavidCarlisle Maybe they decided Python was better, after all?

David Carlisle

@FaheemMitha no:-) new version has more lua less tex, if anything

Faheem Mitha

@DavidCarlisle Maybe in due course it will be all Lua and no TeX.

Though then the name would be inaccurate. They would have to call it LuaNoTeX.

David Carlisle

@FaheemMitha that would be sile

egreg

@Sebastiano Good luck with the new problem style!

Skillmon

@FaheemMitha they brought us peace?

Sebastiano

3:52 PM

@egreg I'm confused for lot reasons. I am not confused about what I will have to do, but because in the document of 15 May, a committee put up stakes that conflict with the rules of the MIUR.

Faheem Mitha

@Skillmon Pax Romana? Punctuated by invasions, mass murder, and theft.

Sebastiano

@egreg I have a lot of ideas but the materials must be texts, passages in poetry or prose, in Italian or foreign language; documents (ideas from newspapers, magazines, photos of artistic heritage and monuments, works of art, .... graphics, tables with significant data; experiences and projects and simple problems in practical and professional cases.

@egreg For physics there were no difficulties in processing them, but for mathematics if you have any ideas send me an email. Thank you very much. A very warm and affectionate greeting.

Ulrike Fischer

:@JosephWright now that luahbtex is called harftex, this checks match(engine,"^lua") in l3build don't work ... and the log normalization is different.

David Carlisle

@UlrikeFischer change to match(engine,"^lua") or match(engine,"^harf") ?

Ulrike Fischer

@DavidCarlisle yes (in two places).

manooooh

4:04 PM

Hello!

I am looking for a template to show some excercises, they include some images. What do you recommend?

Would you do it in beamer, in article, where?

David Carlisle

@manooooh well only beamer if you are presenting it, not for paper, otherwise use whatever class you like article memoir scrartcl ...

manooooh

@DavidCarlisle I said beamer because it has colours, but I am looking for a template which has a lot of colours

David Carlisle

@manooooh add \color{red}

Joseph Wright

@UlrikeFischer Oh ...

manooooh

Something like ^^^^^^^^

@DavidCarlisle you are right

@DavidCarlisle what do you mean by "only beamer if you are presenting it"? (I have a vague idea of what I want)

David Carlisle

4:17 PM

@manooooh I mean beamer makes documents designed to be beamed, ie presented on a big wall with you stood in front, it isn't designed to make something you print on paper (mostly)

manooooh

@DavidCarlisle well, mostly the excersises that I want to make would be stored in a PC

Since the students have their own computer

Also, I'm working with a teacher, and he presents excersises on a TV to all students, and then he shares their document (which is a Word) to the students. They don't print the document but they see it on the monitor

Yeah, I'm sure the students won't print the documents, they will use it on the computer

David Carlisle

whatever happened to blackboards and chalk? :-)

manooooh

@DavidCarlisle I am a teacher of informatic programs, we don't need blackboards very often... :P

Of course they are still used, they have an apogee with the digital whiteboards

Alan Munn

4:35 PM

@DavidCarlisle A constant battle in our classrooms. The blackboards are there, but the cleaning staff routinely don't restock the chalk. Whiteboards on the other hand are the spawn of Satan.

manooooh

@AlanMunn we love whiteboards

Whiteboards that use chalk I consider them old. Fibrons are better

Alan Munn

@manooooh Whiteboards 1) are dirtier 2) are harder to clean 3) generate tons of plastic waste. 4) Markers are unreliable compared to chalk 5) Markers are more likely to be stolen than chalk. 6) Markers are more expensive than chalk. Whiteboards have no redeeming qualities.

manooooh

@AlanMunn chalkboards 1) are very difficult to write, since it has porous and too many imperfections, 2) it is possible that as you write you hear an annoying noise, 3) the chalks are easily broken, and you have a lot of chalks split around the chalkboard, 4) they produce annoying dust, 5) it is annoying to use any geometry instrument (ruler, compass ...)

David Carlisle

@UlrikeFischer I hate saving tlg files :(

Alan Munn

@manooooh White boards produce a much more annoying kind of dust. And to me the environmental costs (and overall costs of markers) overwhelm any of the supposed downsides of chalkboard.

Faheem Mitha

4:56 PM

@manooooh digital whiteboards? What are those?

@AlanMunn When I used whiteboards, I preferred them to blackboards.

I never noticed any dust.

Chalk, on the other hand, produces dust aplenty.

manooooh

Lightboard (a.k.a. learning glass)

►

Digital whiteboard is a wrong term if you want, I meant to be "Transparent board"

Faheem Mitha

@manooooh Ooh. Fancy.

Alan Munn

@FaheemMitha It's black, and stains everything it touches. I assume it's bits of the marker tip that comes off as you write. It's not dust in the same way that chalk dust is.

Faheem Mitha

@AlanMunn I don't recall that, but it's been a long time...

Do you do a lot of classroom teaching?

manooooh

@FaheemMitha I started teaching to grad students (from 12 to 18). I'm an auxiliar teacher of Informatic programs, and we rarely use whiteboard, we use a computer

Alan Munn

4:59 PM

@FaheemMitha Yes, 2 courses/semester. And mainly with chalk. I use handouts for grad classes as well. But we have a whiteboard in our lab. I use Beamer for presentations, but not for teaching (mainly because if the material I teach.)

Faheem Mitha

@manooooh Computers are good. I suppose you project the screen? I recall doing that too, once. Maybe twice.

@AlanMunn Ok. So you prefer chalk to whiteboards?

@manooooh Of course, if your computer developed a problem during the class, you have a problem.

Alan Munn

@FaheemMitha Yes, absolutely. Especially for teaching. In the lab I have mixed feelings, but we didn't have a choice.

Faheem Mitha

@AlanMunn Ok.

Alan Munn

@FaheemMitha I do have a whiteboard at home.

manooooh

@FaheemMitha yes! This is our room:

Faheem Mitha

5:05 PM

@manooooh Pardon? What is your room?

manooooh

@FaheemMitha and we sometimes do have problems with the main computer... :(

Alan Munn

@FaheemMitha I assume @manooooh means this is a sketch of his classroom.

manooooh

@AlanMunn yes :P

Alan Munn

@manooooh Sadly, not done using picture mode. @DavidCarlisle will be disappointed.

manooooh

Hahahaha oh no! What is my punishment?

Faheem Mitha

5:08 PM

@manooooh What university do you teach at?

manooooh

@FaheemMitha I don't teach at university, altough I'm studying in one (Universidad Tecnológica Nacional - Facultad Regional Buenos Aires). I teach to undergrad? students, namely students in range 12-18

Alan Munn

@manooooh In N. America we would call those high school students; you are an undergrad (= in university working towards first degree).

manooooh

@AlanMunn thanks for the clarification! I will not get confused anymore

Faheem Mitha

@manooooh I see. So Argentina?

I thought you were Indian.

manooooh

@FaheemMitha yup

@FaheemMitha lol no! Do you teach?

Faheem Mitha

5:18 PM

@manooooh I used to.

David Carlisle

@FaheemMitha there is a flag on that duck

manooooh

@FaheemMitha what do you do now?

Faheem Mitha

@manooooh Hard to give a good answer to that question. Nothing much. But I still seem to be quite busy.

manooooh

@FaheemMitha that is nice. What did you teach?

Faheem Mitha

@manooooh Math and Statistics.

Mostly elementary/remedial levels.

manooooh

5:22 PM

@FaheemMitha I don't like Statistics so much, but I love Math. Congratulations for your great contribution to a better world!

Harald Hanche-Olsen

5:37 PM

@AlanMunn I always bring chalk when I go to lecture. Doesn't everybody?

manooooh

@HaraldHanche-Olsen yes! In some places there are a locker in the room where the teachers drop their chalks, markers, erasers etc. Others just bring from their houses!

Harald Hanche-Olsen

@AlanMunn And sooner or later, most likely sooner, someone will use a permanent marker on the whiteboard.

Skillmon

@manooooh I remember that I was often sent to grab some chalk from the janitor's office back when I was in school.

manooooh

@Skillmon my experience was similar but with marker ink repository :)

Skillmon

@manooooh we then hat rotational blackboard duty, two students who were responsible for a week that the blackboards are clean at the beginning of each lesson and that there was enough chalk in the room.

David Carlisle

5:44 PM

$ git commit -a -m "regenerate test results with wider log lines"
[master 45b8e61] regenerate test results with wider log lines
 71 files changed, 2207 insertions(+), 4633 deletions(-)


$ git push

@UlrikeFischer ^^

manooooh

@Skillmon that is fantastic! Good for the school and for students, because you and the others students learned how to take care of things

Skillmon

@manooooh I didn't learn that in school, being responsible for something is what was practised in my family with the chores, the boy scouts, ...

Harald Hanche-Olsen

@Skillmon Ooh. When I first started teaching in my present job, there were janitors cleaning the boards between lectures. But no more. Now, I have to start most lectures cleaning the board after the lecturer before me. It makes me doubly mad because I always cleans the board after my lecture, because I think that is how it should be done.

Ulrike Fischer

@DavidCarlisle let's look ...

manooooh

@Skillmon that is important, even more important that in school. However, it is not less harmful to teach that to the students, since many parents do not teach it and they are not even present... :(

Skillmon

5:47 PM

@HaraldHanche-Olsen yes, that's indeed how it should be done. But seriously, janitors cleaning the backboard between each subject/lesson seems a bit over the top, imho.

mickep

@HaraldHanche-Olsen Oh, I think you should give the students coming after your class the joy of seeing what was going on before in the classroom! :)

manooooh

@HaraldHanche-Olsen that is true. Some teachers forget to clean the board and some others don't have that practice learned... That is sadly bad. In my school, the boards are cleaned by Maintenance once a day, or once a week

@mickep some ask, they must be 5% (unfortunately!)

Harald Hanche-Olsen

@mickep And scare them with PDE estimates too long to fit on the board?

mickep

@HaraldHanche-Olsen Oh, yes!

manooooh

Let's put an integral or PDE to 12-year-old-students and we will scare them!

mickep

5:54 PM

@manooooh If something is written on the boards when I enter the class room, I usually comment to the class about it, if possible.

manooooh

@mickep you can do it, it seems good to me. What I do not like is that the students do not pay attention. How many could pay attention to you? It does not happen very often here

mickep

@manooooh I agree that it is not so nice with students not paying attention, but if I have 150-200 students, I count there will always be some of them who cannot keep up for one or other reason. I don't know how big classes you have?

manooooh

@mickep that's also true. We have 20-30-40 alumns per course. The point here is that <50% pay attention. When the students came to the informatic room, they sit down, they eat, they talk to each other. We, the teachers, don't have enough time to show them fancy things, like what is written in the whiteboard when we entered. We have 1 hour = 40 minutes of class, 2 hours = 1:20 hours of class, and the students has at most 2 hours with us (4 per week)

mickep

@manooooh Oh, sounds a bit bad. What do you do about those who talk to each other? I tell them it is disrespectful against their friends, and that usually helps.

manooooh

@mickep we usually request silence. We lose 10-15 minutes because of asking for silence, or waiting for students to come in to the room, or searching for the files we need to share with their (we usually use Word or PowerPoint. I know, it's not good to talk about these programs in TeX - LaTeX :P)

Other 10 minutes for questions of students regarding "Where do I leave my work?" or "Where do I leave my pendrive?"

David Carlisle

6:09 PM

@manooooh I see Argentina is in same group as England in women's world cup (England just won their match:-)

manooooh

@DavidCarlisle oh really?!?! What sport/s are you talking about?

David Carlisle

@manooooh football

manooooh

@DavidCarlisle yes. Good news. I do not see this can serve to improve education

Does someone know how to place these pictures?:

Forget, I found \begin{minipage}{\textwidth}

marmot

@manooooh Depends on which packages you are loading. If none, you could just add a tabular with \raiseboxes.

manooooh

@marmot thank you

Does someone know how to change "Example" label of \begin{examples} in beamer class?

Alan Munn

7:01 PM

\documentclass[spanish]{beamer}
\usepackage{babel}
\newtranslation[to=Spanish]{Examples}{Exemplos}
\begin{document}

\begin{frame}{A frame}
\begin{examples}
 An example
\end{examples}
\end{frame}
\end{document}

@manooooh ^^^

(Pardon my portenhol.)

@manooooh Actually you don't even need to load babel or specify the language. So you could just add \newtranslation{Examples}{Exemplos} and it would work too.

Ulrike Fischer

8:23 PM

@DavidCarlisle I still get failures. E.g. with accsupp-test1. But I really don't understand, why you/the tlg has a line break before (kvoptions.sty.

David Carlisle

@UlrikeFischer hmph that was the first failure I had before. Can you send me your raw log for that one?

@UlrikeFischer oh 200 isn't enough... If I run it by hand the terminal output shows the problem

$ max_print_line=200 pdflatex testfiles/accsupp-test1.lvt

produces

(./accsupp.sty (./pdfescape.sty (./ltxcmds.sty) (./pdftexcmds.sty (./infwarerr.sty) (./ifluatex.sty) (./ifpdf.sty))) (/usr/local/texlive/2019/texmf-dist/tex/generic/ifxetex/ifxetex.sty)
(./kvoptions.sty (/usr/local/texlive/2019/texmf-dist/tex/latex/graphics/keyval.sty) (./kvsetkeys.sty (./etexcmds.sty))) (./accsupp-pdftex.def))

@UlrikeFischer with a line break

with $ max_print_line=2000 pdflatex testfiles/accsupp-test1.lvt

it all comes on one line

(./accsupp.sty (./pdfescape.sty (./ltxcmds.sty) (./pdftexcmds.sty (./infwarerr.sty) (./ifluatex.sty) (./ifpdf.sty))) (/usr/local/texlive/2019/texmf-dist/tex/generic/ifxetex/ifxetex.sty) (./kvoptions.sty (/usr/local/texlive/2019/texmf-dist/tex/latex/graphics/keyval.sty) (./kvsetkeys.sty (./etexcmds.sty))) (./accsupp-pdftex.def))

@UlrikeFischer I'll rebuild with it set to 10000?

Ulrike Fischer

@DavidCarlisle do you have a batch file or should I get a list of the problematic tests to reduce the number of tests to resave?

David Carlisle

@UlrikeFischer I'll run the whole lot, see what happens...

@UlrikeFischer even some that pass will change as the line breaks will go so I need to regenerate them all anyway

Ulrike Fischer

@DavidCarlisle true.

David Carlisle

@UlrikeFischer thanks for the mai

manooooh

8:42 PM

@AlanMunn no problem! It is "Ejemplos" for "Examples"

@AlanMunn true, it worked for me, thanks!

Regarding this:

21

A: How to set a small default font size with beamer?

According to section 18.2.1 of the beamer manual, a default font size of 8pt is already "way too small". beamer uses the extsizes packages for non-standard font sizes, and extsizes doesn't offer anything smaller than 8pt. If you really must fit more text on each frame, I suggest to enlarge beamer...

I followed the answer and set \geometry{paperwidth=140mm,paperheight=105mm}. Do you recommend this size?

I want a higher size since the slides are too small for my presentation. What size do you recommend or what scale do we need to use?

Alan Munn

@manooooh I don't think you should be using geometry with beamer.

manooooh

@AlanMunn ok. Any suggestion on how to increase the slides size?

Alan Munn

@manooooh tex.stackexchange.com/q/354022/2693 maybe?

manooooh

@AlanMunn maybe. Do you know the default values of the 4 margins? I want to change based on the default values

egreg

Another chapter in the “missing percent syndrome” saga: github.com/reutenauer/polyglossia/issues/224

2

manooooh

8:53 PM

@egreg uhh LOL! The % symbol is used for comments, too, isn't it?

David Carlisle

@manooooh @egreg has got almost all his points from that one answer

egreg

@manooooh Not only, as you saw. In macro code it's used to mask off the end-of-line that would produce a space.

David Carlisle

@egreg that hebrew file has come up with issues before, I think.

manooooh

@egreg nice catch!! I thought (La)TeX will notice the % and ignore it, since it could be used as for comment (and therefore do not take it into account). Now I realize that (La)TeX is smarter than I thought...

egreg

@manooooh When TeX sees it, while reading an input file, it discards it together with everything on the same input line (including the end-of-line).

manooooh

8:58 PM

@egreg but that does not make any sense, since % saved the "unprotected end-of-line" i.e., % was taken into account during the compilation

egreg

@manooooh How can it be taken into account if it's discarded when reading the input file, before TeX performs anything related to typesetting or macro definition?

manooooh

@egreg because, if we say "% does nothing", then if we add or not the % symbol, TeX will compile anyway. But that is not true, since adding % prevents the unprotected EOL i.e. we are saying "% does something"

egreg

@manooooh Did I ever say that “% does nothing”?

manooooh

@egreg I thought it would come off when we agreed that TeX does not take it into account

David Carlisle

@manooooh % comments out the end of line, it is not a special behaviour, it is just how comments work.

manooooh

9:02 PM

@DavidCarlisle well... a comment was designed to describe to the programmer the meaning of a piece of code, isn't it?

What I mean, I don't think that % (in TeX) is only for comment a piece of code; it has more functionalities, as egreg shown

David Carlisle

@manooooh yes but \foobar#1}% and \foobar#1}% this is a line of code are handled the same way, in both cases, tex ignores everything from % to the end of line

manooooh

@DavidCarlisle oh, you are right. I meant that \section{Hi} % Comment and \section{Hi} produces the same

But that is not true in general; \def\proofname{הוכחה} is one thing, and \def\proofname{הוכחה}% is another thing (this is the correct way)

David Carlisle

@manooooh not necessarily. If there is a blank line after that the first one makes a space token, and the second one makes \par

manooooh

@DavidCarlisle I don't know what you mean

David Carlisle

@manooooh tex treats these the same, it ignores from % to end of line in both cases.

manooooh

9:07 PM

I thought they produce the same output, so TeX will "act" the same

@DavidCarlisle but TeX does care about % symbol, am I right?

David Carlisle

@manooooh it starts a comment if that is what you mean by "care"

manooooh

@DavidCarlisle no. As egreg shown, % plays an important role in TeX; it prevents unprotected end-of-lines

David Carlisle

@manooooh that is just saying that ends of lines in comments are commented out.

manooooh

@DavidCarlisle ...when you could spend hours and hours looking for the solution to the problem when the real solution was to add a %. Is not it important to know?

David Carlisle

@manooooh % comment <end of line> ignores the comment and end of line %<end of line> ignores the comment and the end of line, just that the comment is empty, it is the same behaviour

manooooh

9:12 PM

@DavidCarlisle we are agree in % hi and %hi produce the same output. What I'm saying is that % and <nothing> (empty space) are not the same for TeX

David Carlisle

@manooooh no of course not, one is a comment and one not. But you were implying that there is a second use of % aside from its use in comments and that isn't the case

manooooh

@DavidCarlisle well, at least I see two uses: commenting a piece of code and preventing unprotected end-of-lines

David Carlisle

@manooooh you may see them as different, but tex does not

manooooh

To understand better, if % prevents an unprotected end-of-line, then should we use a % in all the source code?

For example:

\documentclass{article}%

\begin{document}%
Text here.%

Another text here.%

If $x+2=5$ then \[x=3.\]%
\end{document}%

We do not always add it because it's annoying to do it for each line, but we should do it, isn't it?

marmot

@manooooh You should not overdo it. You have to do it when it is necessary. When is it necessary? When otherwise something weird happens. ;-)

Alan Munn

9:21 PM

@marmot We also need to give @egreg rep points.

manooooh

@marmot LOL we are not a wise, so for preventing bad behaviors of TeX internal code we should do it? :P

@marmot do you still have the crystal ball?

egreg

@manooooh No, that's not at all necessary.

marmot

@manooooh No, it got stolen.

manooooh

@egreg but it was necessary for the GitHub issue...

@marmot dammit!

egreg

@manooooh It's a very different matter.

manooooh

9:22 PM

Ok, thanks for the clarification

marmot

@manooooh @AlanMunn The % are necessary when they are not unnecessary.;-)

Alan Munn

@manooooh End of line percent signs in your document source are only very rarely needed. The issue mainly arises in macro definitions not in regular documents.

manooooh

@marmot it is a tautology! p if and only if not(not(p))! XD

Paulo Cereda

@manooooh not in non-classical logic

marmot

@manooooh Pssshht.

manooooh

9:24 PM

@AlanMunn ok. I still believe that you can have your own definition of "regular document", and to me it can be a different definition, but I understand your point

@PauloCereda uhh those are unintelligible to me!

marmot

@AlanMunn Advanced species call it the "@UlrikeFischer trick": tex.stackexchange.com/a/448179/121799 ;-) It indeed gives easy rep points.

Alan Munn

@manooooh By 'regular document' I mean not a package or class. But the main distinction is between "in a macro definition vs not". There are very few places outside of macro definitions where an end of line % is needed. (Very few, not none, though.)

marmot

@AlanMunn \foreach turns to be such a place...

@AlanMunn nonlinear transformations, too. Actually, it is rather common.

Paulo Cereda

Will you guys watch Dark Phoenix?

manooooh

No. What is it?

Alan Munn

9:28 PM

@marmot Well very few unless you're using TikZ a lot I guess.

Paulo Cereda

@manooooh The last stand for the X-men movie franchise.

manooooh

Ohh the movie! Nice

David Carlisle

@manooooh you never need to use % you just can use it if you have added white space that you want to comment out, so if in your document you have one two and you change the space to a newline, do not comment out the newline as it would be onetwo but if you add a newline where a space would be wrong, then you can comment it out if you do not want to write the code on one line without a newline.

Alan Munn

@PauloCereda Comic book characters don't resonate with me much.

manooooh

@DavidCarlisle hm, that seems the correct answer

marmot

9:30 PM

@AlanMunn Well, I always thought it is precisely the opposite. Inside a tikzpicture text and in particular spaces get gobbled. So there are only few places where it matters. However, if you play e.g. with foreach or any coding outside you are much more "vulnerable".

Paulo Cereda

@AlanMunn Me neither ,but... Sophie Turner <3

David Carlisle

@manooooh naturally:-)

manooooh

:)

Next level question: can we produce any document without any spaces (and without any %)?

David Carlisle

@manooooh yes of course. \documentclass{article}\begin{document}z\end{document}

Paulo Cereda

@DavidCarlisle ooh z

manooooh

9:33 PM

@DavidCarlisle I said any document, not a document! Haha, but you are right if we say "a document"

David Carlisle

@PauloCereda it's a paradox, a document with no spaces, must be German, but has a z which is impossible to find on a German keyboard.

Paulo Cereda

@DavidCarlisle ooh ze keyboard

manooooh

@DavidCarlisle ohh. Does the Germans not use any spaces?

Paulo Cereda

@JosephWright vvv

David Carlisle

@manooooh no my answer answered your question (I defer to @AlanMunn for the techical details of English Grammar:-)

Paulo Cereda

9:34 PM

> Microsoft today teased some its first plans for Project Scarlett, the next-generation Xbox, and the buzzwords make it sound impressive: up to 120 frames-per-second, a solid state drive, ray-tracing, and so on. It’ll be out in the fall of 2020.

manooooh

@DavidCarlisle hm... you answered for a particular document; I am asking if no spaces are need to produce any document we can imagine

Paulo Cereda

@manooooh Yes.

@DavidCarlisle send him to xii

manooooh

@PauloCereda really? Wow. But how would you insert a new paragraph?

Paulo Cereda

:)

David Carlisle

@manooooh well no in the form you used it above you are asking if there is any such document the reading you intended did not occur to me until after you objected to my answer

@manooooh \par{} inserts a paragraph with no space in the source file.

Alan Munn

9:38 PM

@PauloCereda Meh.

Paulo Cereda

@DavidCarlisle partridges in pear trees. :)

@AlanMunn boo

manooooh

@DavidCarlisle wow! That is true. Hm... let me think a document which needs spaces... :P

"Hello World!" needs one space, isn't it?

Alan Munn

@DavidCarlisle Surelz its the 'y' which is impossible to find.

David Carlisle

@manooooh Hello\space{}World

Paulo Cereda

@manooooh Hello\space{}world

Ulrike Fischer

9:39 PM

@DavidCarlisle Or \ExplSyntaxOn~A~text~with~no~spaces~and~a~few~zzz.

manooooh

OH MY

Paulo Cereda

@DavidCarlisle great minds think alike <3

David Carlisle

@PauloCereda but greater ones are faster

Paulo Cereda

@DavidCarlisle ooh Englishpeople

manooooh

Thank you guys!!

I want to find the \space definition, but I am not finding the latex.sty file :/

David Carlisle

9:46 PM

@manooooh line 116

manooooh

@DavidCarlisle not that (I can use CTRL+F), I mean the link on Windows

David Carlisle

@manooooh huh?

manooooh

I always forget it... I am searching in a txt file of a compiled document but can't find

@DavidCarlisle C:\...

David Carlisle

@manooooh just look in the log file of any document for the path of article.sty and it will be in same place, or kpsewhich latex.ltx

@manooooh but it is not very interesting definition \def\space{ }

Alan Munn

@DavidCarlisle I was expecting \def\space{The final frontier}.

David Carlisle

9:50 PM

@AlanMunn final not last, if I recall correctly?

Alan Munn

@DavidCarlisle That's what I said. :)

David Carlisle

@AlanMunn just in time (benefits of warp speed)

@AlanMunn I suppose that is "serious science fiction" not "comic book characters" ?

Alan Munn

@DavidCarlisle I didn't say Star Trek resonated with me either...

@DavidCarlisle If it had, I wouldn't have had to have edited. (Isn't English wonderful. 4 'have's in one sentence.)

manooooh

@DavidCarlisle ohh, thank you!

Alan Munn

10:51 PM

@touhami Thanks for posting your answer to the Arabic question. I fear that Sandra is quite committed to the arabtex solution, unfortunately. From my talking with here in chat it seems that she has a thesis due next week mostly written with that, so I don't know whether switching to use XeLaTeX would be practical.

Steven B. Segletes

11:50 PM

@DavidCarlisle Your discourse on not being able to add unbalanced braces to token lists was very helpful. One thing I found I could do was add catcode 12 braces to the token list as I went, and then \scantokens the result. But I have no guarantee that the token list is expandable...

@DavidCarlisle ...so egreg's answer using \escantokens at tex.stackexchange.com/questions/213659/… does not apply.

@DavidCarlisle So the question is, is there a simple way to take a token list with balanced catcode 12 braces, and reconvert the token list into catcode 1 and 2 braces, without any further expansion of the token list?

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