{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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2
votes
0answers
81 views

Is there a way to partially evaluate TeX files? [duplicate]

I am looking for tools or techniques that can partially evaluate (e.g. inline definitions) a TeX source file into an equivalent, simplified TeX file with some parameters fixed. Specifically I would ...
3
votes
1answer
66 views

Moving arguments inside group

I have a setup similar to the MWE below in which I have a macro that needs to be called in the document, and also regularly becomes a moving argument (in this case, inserted into the index, though it ...
18
votes
1answer
242 views

Plain TeX online documentation/references?

I am a non-beginner plain TeX user, mostly typesetting cheat sheets for computer science. I own The TeXbook and have seen some TeX manuals for the compilers, such as pdfTeX manuals and so forth. My ...
11
votes
4answers
217 views

How can I compare two (not necessarily integer) variables?

After experimenting and researching for hours, I still cannot figure out how to perform a simple equality test between two numbers. More specifically, here, the two numbers in question are the ...
7
votes
3answers
134 views

Defining tabular rows with macros using `\ifnum` leads to `Incomplete \ifnum`

I am trying to define tabular rows using a macro which shall perform an conditional definition of the tabular row according to a given parameter. Please consider the following MWE: ...
11
votes
4answers
101 views

A question about macro matching

Consider the following macro definition, and subsequent invocation: \def\foo #1 #2 \bar{stuff with #1 and #2 goes here} \foo arg1 arg2 \bar The \bar simply acts as the terminator for \foo. This all ...
20
votes
2answers
208 views

Has a command access to its own name?

Can two commands where the one is a copy of the other so that \ifx gives true have different behaviour depending on the actual name used for a call? \documentclass{article} \newcommand\red{some code ...
3
votes
1answer
116 views

Are there more to applications of \iftrue and \iffalse?

While reading "TeX for the impatient" on the topics of iftrue and iffalse, I encountered this example, \def\isbigger{\let\bigger=\iftrue} \def\isnotbigger{\let\bigger=\iffalse} \def\test#1#2{\ifnum ...
9
votes
1answer
136 views

What can and can't occur as macro argument?

The documentation of the environ package says The advantage to using environments is that their contents is not treated as a macro argument, so there are less restrictions on what can exist ...
5
votes
1answer
59 views

tex using the wrong macro

Out of curiosity I tried to weave the bibtex.web source code and compile the resulting bibtex.tex with tex. I got some errors which led me to investigate; I'm sure my confusion stems from incorrect ...
2
votes
1answer
38 views

superscript issue in latex [duplicate]

I have 2 superscripts in 1 equation but one of these is floating higher than the other making it look messy. The code I have used is: $\hat{\boldsymbol\beta}^T X^T$ The T is higher for the beta ...
133
votes
23answers
6k views

Are there any open research problems in the world of TeX?

For a year-long capstone project in computer science, I have to do some 'original research.' I'm still not entirely sure what this entails, but it just struck me that perhaps I can do research and ...
3
votes
1answer
77 views

only expand next macro if its depictable content is placed at a specific place on the page

I'm looking for a conditional that checks if the visual processor puts the depictable content of the macro that is going to be expanded at a specific place on the page where the content is placed. ...
9
votes
3answers
139 views

Problem with ^^<HEX>

I have small problem with ^^<HEX>. If I have a <HEX> part of the ^^<HEX> in the macro \def\attemp{<HEX>}, I cannot write ^^<HEX> as ^^\attempt or ...
9
votes
2answers
171 views

Is it possible to use $ as a macro delimiter?

Experimenting with macro definitions that use strange delimiters (see e.g. this or this question), I thought it would be fun to have a macro that takes an argument of the form "a/b" and turns this ...
22
votes
1answer
244 views

Is \def sensitive to spacing?

In the code below, it took me a long time to figure out that the space in the second line below beginning with \def generates an error. I'm new here. Where is the documentation of \def that would ...
30
votes
3answers
2k views

Difference between \if and \ifx

I try to understand the subtleties of TeX programming, but it is not always easy. For example, in the following code : \def\first{abc} \def\second{abc} \ifx\first\second OK!\else false \fi I ...
2
votes
1answer
243 views

How to render LaTeX in programs?

Recently I'm writing a calc program, on android. As a frequent LaTeX user, it comes to be compelling to use LaTeX rendering in displaying the inputs and outputs. Is there any possibilities to use a ...
11
votes
2answers
114 views

increase \hyphenation{word1 word-2…} capacity

We use LaTeX to typeset a large collection of books with many proper names. We use the \hyphenation{word1 word-2...} command to specify words that should not be hyphenated and to suggest hyphenation ...
3
votes
1answer
191 views

Tex Custom Arrow with oplus symbol

I'd like to create the kind of arrow that shows inner classes in UML, that is, an arrow that starts with an \oplus symbol as it can be seen here: ...
6
votes
0answers
116 views

Replace paragraphs with boxes [closed]

I would like to replace the paragraphs of a compiled document with framed boxes. Although I read the /tex/latex/base documentations I have no idea how to tackle this problem. In detail I want to ...
19
votes
2answers
380 views

Will LaTeX work on any TeX?

As I understand it, latex is simply a macro package for tex, as in tex the program, not the format. (Again, weird, but I understand LaTeX to be a format of TeX.) Does this imply that LaTeX the ...
10
votes
1answer
150 views

How can latex and pdflatex be both symbolic links to same executable (pdftex) and not behave the same?

When I run $ latex my_doc.tex and $ pdflatex my_doc.tex it works, and when I run $ pdftex my_doc.tex it doesn't work. The thing is I noticed that both LaTeX and pdflatex commands are ...
2
votes
0answers
91 views

How to generate an AFP document by using LaTeX compiler?

I'm working on a new program who have to generate an AFP file. I would like to generate this kind of file by using a powerful language like LaTeX. Because I hate Dialog (HP solution), is there a ...
13
votes
1answer
180 views

What practices are there regarding the use or avoidance of “internal” TeX or LaTeX commands?

What practices are there regarding the use or avoidance of "internal" TeX or LaTeX commands? (About "command" vs "macro", there is some discussion in this TeX.SX answer, though I don't know whether ...
11
votes
1answer
181 views

TeX capacity exceeded, sorry [semantic nest size=500]

Reading through tex.web, I note that there is a difference between grouping levels and semantic nesting (i.e., the nesting of math, horizontal, and vertical modes). I can think of commands which ...
29
votes
1answer
905 views

How to generate “You can't use \unskip in vertical mode”?

We all know (or believe so) that \unskip is not possible in main vertical mode and this statement can be found in various answers on the site. And yes LaTeX does a lot of gymnastics in \addvspace or ...
4
votes
1answer
126 views

How to make a rich png image from a Latex Math Equation [duplicate]

I have a LaTeX math equation that I have been trying to convert it into a rich .png image by compiling the .tex file into .dvi and then from .dvi to .png. But I noticed that the Image is small and the ...
3
votes
1answer
96 views

Hook tex macro without altering tokens stream

Is is possible to hook a macro with function which writes some info to file or log without altering stream which creates dvi file. For example if i have macro definition \def\foo{\mathop{A}} and i ...
9
votes
1answer
101 views

Interactively look up macro definitions

In a TeX document, the primitive command \show will print out the current definition of a macro one level deep (it won't (and can't?) reduce to primitives). This comes with the restriction of actually ...
2
votes
1answer
346 views

How to convert an A5 document (PS or PDF) to an A4 document (PDF)?

I have a document with A5 pages (created from a TeX file) and want to combine pairs of A5 pages to A4 pages. That is, without scaling, page 1 and 2 of the A5 document should become page 1 of the A4 ...
15
votes
2answers
256 views

Use of \everyeof and \endlinechar with \scantokens

The e-TeX \scantokens primitive allows retokenization of input. However, it is almost always used in a group where \everyeof and \endlinechar are set (see for example Can I convert a string to catcode ...
16
votes
3answers
250 views

Can I convert a string to catcode 11?

In the TeX FAQ there's a way to test if the jobname is equal to something (comparing the jobname). The difficulty of the naïve test is that the contents of the \jobname primitive are catcode 12 so to ...
18
votes
1answer
288 views

Drawbacks of redefining math accents with extra leading {}?

As I discovered through the non-bug latex/4253, TeX has a (mis)feature whereby it ignores braces around a \mathaccent construction: ${a_b}_c$ works, but ${\tilde a_b}_c$ fails with a "Double ...
7
votes
1answer
367 views

Is there likely to be an xpsTeX?

The 2007 TUG April Fools' announcement was pretty funny, but does this idea have any traction whatsoever? From a design point of view, XPS may be the starting point for future document formats beyond ...
12
votes
2answers
136 views

What would be a suitable replacement for ifcsname in a non-etex situation?

From the pgfkeys.code.tex file: % This is useful: \def\pgfkeys@ifcsname#1\endcsname#2\else#3\fi{\expandafter\ifx\csname#1\endcsnam e\relax#3\else#2\fi}% \ifx\eTeXrevision\undefined% \else% ...
11
votes
2answers
378 views

Is a TeX macro defined?

I am looking for a way in TeX to check if a macro was defined. Currently I use a rather tangled way. I exploit a sort of side effect when comparing two macros via \ifx; this command returns: true, ...
27
votes
3answers
612 views

Why doesn't TikZ's \foreach iterate over the last element of the list?

This code \documentclass{report} \usepackage{tikz} \begin{document} \begin{tikzpicture} \draw[dashed] (1,-1) -- (1,2) node[above] {$1$}; \draw[dashed] (2,-1) -- (2,2) node[above] {$2$}; \foreach ...
51
votes
3answers
3k views

2013, year of the TeX bugs report. Will pdfTeX, XeTeX, etc. be changed accordingly?

Barbara Beeton said (TUGboat vol. 34, pag. 4): As noted on Don Knuth's TeX web pages, www-cs-faculty.stanford.edu/~knuth/abcde.html, he "intend[s] to check on purported bugs again in the ...
11
votes
4answers
164 views

Partially expanding a command

My \john command is defined like so: \def\john{\DontExpandMe} I would now like to repeatedly change its definition, to keep adding some extra stuff on the front. \foreach\i in {ape,bat,cow,dog} { ...
51
votes
2answers
1k views

If LaTeX is only a macro package, why does it have its own executable?

From other answers on this site and the FAQ of the TeX User Group my understanding is that: TeX is the original typesetting program, written by Knuth Omega, eTeX, pdfTeX, XeTeX, LuaTeX are engines. ...
17
votes
1answer
125 views

What primitives can expandably tell us about the current horizontal list?

I've been writing some code that expands macros and catches characters and non-expandable primitives as they reach TeX's stomach, and I encountered an issue: since I gather letters one by one, with ...
7
votes
2answers
470 views

Highlighting haskell listings in large *.tex document [duplicate]

Suppose, there is a large *.tex document, which has many nested \input directives with many Haskell listings surrounded by \begin{code} \end{code} commands. How can all this code listings be ...
7
votes
1answer
522 views

TeX ignores \vskip at the beginning of document

Here is a simple Plain TeX snippet for demonstration \vskip 3in Aaaaa \vskip 3in Bbbbb \end When I compile this with pdftex, I expect to see a 3-inch-high blank space, then Aaaaa, followed by ...
6
votes
2answers
218 views

Learning how to use TeX for automatic layout of non-technical documents

Whenever I try to learn more about TeX or LaTeX, I am stymied by the general bias of the books and online resources I have seen, and possibly by the bias of LaTeX itself. I am not interested in using ...
7
votes
0answers
79 views

What is the difference between \def and \newcommand (Part II)? [duplicate]

A previous question What is the difference between \def and \newcommand? has discussed the difference between \def and \newcommand at some length. However, I cannot find in that discussion an ...
40
votes
1answer
613 views

On the basics of writing to & reading from auxiliary files (.aux, .toc, etc.)

Some actions (such as generating the Table of Contents) require two passes of the TeX compiler: during the first pass, some data get written to an auxiliary file, only to be retrieved during the ...
13
votes
5answers
274 views

Checking if a string contains # with its original catcode

At comp.text.tex the following scheme was suggested for testing if a string contains the parameter character with catcode 6. \def\endcheck{\endcheck} \def\second#1#2{#2} ...
8
votes
2answers
110 views

\setbox containing maths interferes with surrounding math mode in XeTeX

I encountered what might be a bug in XeTeX (but I would be glad to be proven wrong) while chasing a strange interaction between bytefield, unicode-math, and mathtools. In general, I do not expect a ...
41
votes
3answers
1k views

Why no vertical-mode Knuth-Plass?

I have only basic knowledge of the TeX internals, so I hope what I am saying here is not complete nonsense. If I understand correctly, in TeX, horizontal positioning / line breaking is done using a ...