{tex-core} is for questions that are independent of formats and macro packages. Such questions usually relate to low-level TeX programming or the behaviour of TeX at an underlying level. Note that even Plain TeX is a format in itself; for questions about it, use {plain-tex}.

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4
votes
0answers
114 views

Is TeX “typeset complete”? [closed]

Occasionally, I see a question on TeX StackExchange where my first idea is "this can't be possible". Yet there always seems to be a way to do exactly what was asked for in TeX. Can TeX, in principle, ...
1
vote
0answers
66 views

How convert any.text to any.tex file or html file to tex [closed]

I found examples where it is mentioned conversion of tex files with LaTeX, but to get any file to tex I could find. In the Linux console. UTF-8 does not support the Russian alphabet or Arabic. If you ...
1
vote
0answers
90 views

Reference of Latex/Plain Tex control sequences [closed]

I'm looking for a reference of the control sequences defined in Latex and plain Tex similar to this one for the build-in primitives. The Texbook states that there are about 600 macros in plain Tex. ...
36
votes
4answers
2k views

How does your mind bend \expandafter to its will?

Expansion is often cited as one of the most arcane aspects of TeX, more akin to witchcraft than to something easily picked up by the newcomer. There are many great questions and great answers about ...
20
votes
2answers
598 views

The role of %&latex at the beginning of a source latex file

Could someone please explain what is the role of %&latex which is put in a source LaTeX file before \begin{document} command?
2
votes
1answer
76 views

Count “a” in text not in math mode, verbatim or lstlisting

I would like to count the "a" word in a text and put output to the PDF file, eg. This is a document about processing text in TeX. The document has a new macro but $a = 10$ is not counted, nor ...
10
votes
2answers
87 views

\csname not working as expected

The following code prints ==atname== \def\atname{atname} \def\xxx{name} \def\at{at} ==\csname\at\xxx\endcsname== \bye but this does not: \def\@name{atname} \def\xxx{name} \def\at{@} ...
12
votes
1answer
299 views

Is Knuth's *The TeXBook* complete?

Suppose I want to learn TeX. Then, is The TeXBook a complete source? Does it cover all relevant aspect of TeX? Or is there something worth learning about TeX which is not present there? Does also ...
1
vote
1answer
44 views

Pre-compiling with a different syntax [closed]

I am looking for a pre-compiler to introduce a customized syntax into LaTeX. Hope that an example will be worth a thousand words: I would like to compile this \thm The sum $ 1+2+3 is equal to ...
6
votes
2answers
64 views

Different Behaviors Digesting \csname x\endcsname and Digesting \x (expansion issue)

This question has been significantly EDITED, as I learned more of the problem. If I was good, I would be able to create macros with multiple optional arguments, but not only can't I, but in this ...
17
votes
2answers
367 views

Why does this simple \ifx test fail?

This should be easy, but I don't understand why the test below fails... I expected Hurrah! to be printed when the \currentchar count reaches 90 (i.e. the character code of Z). There must be some ...
44
votes
4answers
2k views

What is “expansion”?

I'm relatively new to (La)TeX, but I have a reasonable amount of experience with computational programming languages. Until I began learning (La)TeX, I'd never heard of "expansion"... So, what is ...
2
votes
0answers
90 views

Why does LaTeX impose a memory limit of 8,000,000 and can I circumvent it? [duplicate]

A few people have already asked the question of how to increase the maximum memory LaTeX is allowed to use (see here and here) because it is quite common for LaTeX to run out of memory when using, for ...
33
votes
4answers
645 views

How does a TeX engine read and render the input stream?

I am new to TeX programming and I have not finished reading the TeXBook yet. I need at a glance tutorial about how a TeX engine reads, processes, and produces its output. My mental model as a newbie ...
23
votes
1answer
350 views

The \lowercase trick

We have a number of questions or rather answers using (and explaining) the \lowercase “trick”. \begingroup \lccode`\~=`\. \lowercase{\endgroup\def~}#1{foo with #1} However, after reading on ...
5
votes
0answers
61 views

Namespace in luatex

Is it possible from luatex access registers where all names of command sequences are stored. Is it possible to pull out this list of names? I am looking for a way to trace how namespace changes during ...
3
votes
1answer
75 views

What can I do if I want to have a system for compilation to (AMS) LaTeX regarding restrictions to user-defined macros?

So I want to have a system where some user document is fully processed by TeX engine (full TeX engine!) and some data is collected to some helper file (saying "helper" just not make you think it's ...
76
votes
2answers
6k views

What's new in TeX, version 3.14159265?

The new Knuth TeX has been released in early this month, and its version number is 3.14159265 now. It can be downloaded here. What's new in this release? And a further-more question, where can one ...
7
votes
1answer
255 views

debug No room for a new \write problem

I have a template with an extensive documentation. (See TemplateDocumentation.pdf). It compiled several month ago. Now with updated packages it does not compile anymore because of the famous No room ...
8
votes
1answer
136 views

Cut last word from sentence one by one

I want to execute particular command for some space separated list as argument. And then execute the same command for the same list without last element and do it until list is empty. As extra point ...
6
votes
2answers
172 views

Counters and macros?

Not sure how I should post my question but here it is: I've seen that in plain TeX, \newcount is illegal inside a macro \definition. Is there a way to allocate a register inside a macro? Also, if I ...
3
votes
0answers
144 views

Can (La)TeX be a compelling technology for the humanities, journalism, and other non-technical disciplines? [closed]

All over the web, I see how LaTeX has been successful as a way of describing mathematical notation, which makes it pretty easy to argue that it is a compelling technology for science, technology, ...
6
votes
2answers
154 views

Allowing first undelimited argument to be empty

Consider the following macro definitions: \def\mymacro#1{\mymacroii#1\nil} \def\mymacroii#1#2\nil{% \ifx\\#1\\% empty% \else #1% \fi }% \mymacro{foo}% -> f \mymacro{} \bye This is ...
3
votes
1answer
58 views

Alignment problem or the height of one text line for \footnotesize text

I want to align the arrows so that it goes directly through the "x". How can I do this? It works if I use \normalsize font. The background is that I want to separate my Tikz document in text rows ...
8
votes
1answer
80 views

Hyphenation of the word “paraboloid”

It seems like my TeX does not hyphenate the word "paraboloid" on its own. After adding \hyphenation{para-boloid} (I hope that's the right hyphenation...) to the preamble everything is fine. My ...
23
votes
2answers
511 views

Backward definition of (La)TeX commands

Again and again I see, that TeXnicians define commands and do several things with them in the reverse order, I would do this as amateur. See this example: In his answer to scrpage2: Three ...
5
votes
6answers
409 views

A meta-language for LaTeX

Whenever I write TeX/LaTeX documents, I always find that annoying because I can't really focus on the content, It's not that I don't like TeX or what it does for me, it's just the fact that the ...
5
votes
1answer
245 views

Changing page margins in {pdf-,Xe-}TeX

In TeX, changing the \hsize and the \vsize changes the main text size and the page size of the dvi output. When I compile a document with pdftex or xetex, the page size remains at A4. How can I change ...
12
votes
2answers
407 views

All about \shipout

While reading about packages that allow to hook macros to certain events, I came across this command, \shipout. Searching on the internet didn't help a lot but if I'm not so wrong it's somehow related ...
6
votes
2answers
375 views

Can you do all what you want with TeX?

With LaTeX, I know you can put pictures in the documents, use different fonts, ... and practically do whatever you want (except the fact that your document must have a predefined style, imposed by the ...
6
votes
1answer
76 views

Getting the page breaks right for a \beginsection macro

I've found this code in the question No indent in the first paragraph in a section in Plain TeX \def\mysection#1{% \goodbreak \vskip2\baselineskip \noindent #1\par \nobreak ...
7
votes
3answers
194 views

How can I parse the first word in a token stream, token by token?

Some programming editors and IDEs highlight legal and illegal variable names in different ways. I wish listings easily allowed for such syntax checking and highlighting, but it doesn't, at least at ...
11
votes
1answer
145 views

XeTeXpicfile in vertical mode

Given a minimal like \line{% \vtop{\hsize=.6\hsize Lorem ipsum dolor sit amet, consectetur adipiscing elit. Suspendisse tempor lectus sit amet laoreet convallis. Quisque at est lacinia, porttitor ...
0
votes
0answers
37 views

How can the following table be created in LaTeX [duplicate]

I have asked this question here, and asking it once again, as it was marked as duplicate, although it is different from the links that were pointed to be the same as the question. So, how can I ...
6
votes
3answers
139 views

Why cannot the word in the last column be centered

I have the following table: \begin{tabular}{|p{3cm}|p{1.5cm}|p{1.5cm}|p{1.5cm}|p{1.5cm}|} \hline \centerline {image} & \multicolumn{2}{c|}{ABC} & \multicolumn{2}{c|}{DEF} \\ \hline & ...
14
votes
2answers
189 views

What is the easiest way to modify catcodes in a string?

Assume that a token register contains a sequence of letter tokens, each having a catcode of 12. I want to store in a second token register the same sequence of letter token, altering some catcodes on ...
0
votes
0answers
29 views

Inserting a line break in a formula [duplicate]

I have the following formula in LaTeX: \begin{equation} =\sqrt[m]{\mid C_{new}\left(pi\right)-f\left(pi\right)\mid^{m}-\mid C_{k}\left(pi\right)-f\left(pi\right)\mid^{m} ...
5
votes
2answers
163 views

How to get character code defined with \let (! Improper alphabetic constant)

Here's a example with the "! Improper alphabetic constant" error: %% this is ok \newcount\mychar \mychar=\number`a\relax \showthe a % shows You can't use `the letter a' after \the ...
4
votes
2answers
118 views

How to define a command \exponent that transforms $\exponent^e$ to $a^eb^ec^e$?

I have tried to define a command $\exponent$ that would look for next exponent and would put a copy of this exponent after a, another after b and a last one after c. $\exponent^e$ would transform to ...
9
votes
3answers
321 views

How to force LaTeX only commands?

Recently, I learned that for a long time I have been doing all of my mathematics in LaTeX incorrectly! I was using the $ TeX commands instead of the \( and \) LaTeX commands! I immediately went back ...
3
votes
0answers
56 views

Tex document that displays its own source code [duplicate]

Just out of curiosity, I was wondering how it is possible to write a LaTeX document which, when compiled, generates a document that contains exactly its own source code (i. e. a quine). Since LaTeX ...
38
votes
2answers
499 views

How to implement (low-level) arrays in TeX

Update: I have revised my question based on the comment by Bruno Le Floch and some further research. As some may know, I'm implementing a huge TeX macro package which has to do a lot of internal ...
12
votes
1answer
296 views

What does \empty do? [duplicate]

What does it do and what are its applications? I am currently testing the subtitle of my beamer presentation for its string length to decide about line spacings. Could it be simpler using \empty? If ...
10
votes
1answer
112 views

TeX doesn't recognize built-in control sequences?

I'm trying to learn to build things from the ground-up with TeX (not LaTeX---I've used LaTeX before, so I know how easy a solution "\usepackage{amsthm}+\begin{theorem}" is) and I'm trying to build my ...
6
votes
0answers
78 views

Testing if inside \halign [closed]

I am trying to write a macro that has a different behavior when called from text mode, math mode, display math, and math tables. The first three are easy enough with \ifmmode and \mathchoice. But the ...
0
votes
0answers
188 views

Weird behaviour in Texmaker (Changing the papersize)

I'm trying to change the page size in a tex document (I want a letterpaper size). I'm using Texmaker and the sequence Latex -> Dvips -> ps2pdf and my code is \documentclass[letterpaper]{report} ...
9
votes
2answers
908 views

\llap (or \rlap) at the begining of an indented paragraph

If I use a \llap{text} command at the begining of an indented paragraph, the text is not indented and is put on the line above the paragraph. \documentclass{article} \begin{document} \parindent=2cm ...
1
vote
1answer
179 views

ConTeXt: How to display last page number (Page # of #) in header/footer?

In LaTeX, I could do something like: \fancyhead[R]{\HeaderFont{\thepage{}/\pageref{LastPage}}} and/or \fancyfoot[R]{\FooterFont{\thepage{}/\pageref{LastPage}}} How to achieve the same with ...
0
votes
1answer
144 views

ConTeXt: How to maximize width of column depending on fixed sizes of other columns?

In LaTex, I could do something like: \newcolumntype{C}[1] {>{\centering\let\newline\\\arraybackslash\hspace{0pt}}p{#1}} \newcolumntype{L}[1] ...
7
votes
1answer
875 views

\newcounter vs \newcount [duplicate]

What are the differences between \newcounter vs \newcount? So far as my knowledge goes \newcounter is from LaTeX and \newcount is from TeX. Also, I find that \newcounter has an optional automatic ...