Questions tagged [catcodes]
{catcodes} is about "category codes" — an integer number from 0–15 associated to each of the 256 character codes. The category codes indicate the role of a character.
353
questions
0
votes
1
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33
views
Parsing colon-delimited macro argument (with possible catcode changes)
I try to define a macro taking as an argument either a number or a colon-delimited range of numbers, e.g. \macro{3.14} or \macro{2:5}. I can parse the colon easily using a simple trick:
\def\macro#1{
...
- 289
3
votes
1
answer
78
views
Robustness of \peek_analysis_map_inline:n with changed catcode
Background
Following my previous question I try to make compatible the redefinition of the circumflex ^ catcode with the active prime ' defined in vanilla LaTeX or by the package unicode-math.
The ...
- 4,246
1
vote
0
answers
46
views
Redefine commands, changing a catcode
Background
I'm the author of the altsubsup package, which set to 12 (other) the catcode of the circumflex ^ char.
As it, expressions as x''^2 raise a Double superscript error because the latex ...
- 4,246
2
votes
1
answer
120
views
Automatically substitute hyphen(-) with \ensuremath{-} inside of the table environment
Because, in my usage, most of hyphens(-) used inside of the table environment represent the minus sign, I would like to substitute them with \ensuremath{-}.
Here's my try:
\documentclass[10pt]{article}...
- 925
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1
answer
19
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How can I use escapeinside within a minted environment with the bash lexer?
The escapeinside functionality doesn't work properly with the bash lexer. Is there any way to fix this?
MWE:
\documentclass{article}
\usepackage{minted}
\begin{document}
\begin{minted}[escapeinside=|...
3
votes
2
answers
84
views
Changing a catcode of WolframAlpha output character
Sometimes I exploit WolframAlpha to do some simple calculations and then insert results in my latex code. But I find annoying to adapt the output given by WA to the LaTeX syntax.
When the output is a ...
- 107
2
votes
1
answer
54
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verbatim mode and carriage return character tokens
This question refers to how the program TeX creates tokens after reading a line of a .tex-file. It does actually not refer to writing macros or doing typesetting work which takes place in stages after ...
user301872
2
votes
3
answers
183
views
Can't compare clist item with string
I can't compare comma list item with string. \clist_a is a temp var.
\documentclass[12pt]{article}
\usepackage{expl3}
\begin{document}
\ExplSyntaxOn
\clist_new:N \clist_a
\keys_define:nn { mymodule }
...
- 447
0
votes
1
answer
36
views
Preserving newlines and spaces while writing argument to a file
I am making a function that should write its argument to a file (for further processing by Python)
From the following question I get something that mostly works.
Adding newlines while writing text to ...
- 497
2
votes
1
answer
107
views
htlatex breaks down when using siunitx
I have a manuscript that is written in LaTeX. After a couple of rejections and modifications, the new journal seems to only accept .docx files. I plan to convert my manuscript to a .odt as the editor ...
- 982
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0
answers
71
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Starting command using “/“ instead of “\”
This seems like a very random question, but I just got the Apple Magic Keyboard for iPad Air 5th generation. The key “\” is half of the size of that of “/“. The “\” key is placed also in the edge and ...
- 101
0
votes
3
answers
160
views
How can I change the catcode within a command, then reference input using the new catcode?
pdfTeX: I am attempting to define a command which
takes an input,
redefines the catcode and function of a character, and
prints the input using the new character definition.
I recognize that this is ...
- 15
4
votes
2
answers
388
views
Show carriage return by changing its catcode in TeX?
On page 46 of The TeXbook, there is
TEX deletes any space characters (number 32) that occur at the right end of an input line. Then it inserts a return character (number 13) at the right end of the ...
- 2,115
0
votes
1
answer
75
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"\escapechar" vs category 0 in TeX
In TeX, \catcode`\|=0 will make escape character to be |, to |TeX will output
But at the penultimate paragraph of page 40 of The TeXbook, it says that \escapechar is normally TeX's internal code for ...
- 2,115
1
vote
1
answer
123
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To make "\" to category 12, why should convert it to category 13 in TeX？
Exercise 7.5 on page 40 of The TeXbook asks to make \ to category 12. The answer of this question is
{\catcode‘/=0 \catcode‘\\=13 /message{/string\}}
Why should assign the \ to 13 not 12?
The ...
- 2,115
0
votes
2
answers
77
views
Need add a space before character in changing category of character?
At the bottom of page 307 of The TeXbook, it says
TEX always reads the token following a constant before evaluating that constant.
So,
{\catcode‘\>=2 >
is different from
{\catcode\`>=2>
...
- 2,115
0
votes
2
answers
75
views
Remove all instances of {} interior to argument to a command
Is it possible to remove all instances of {} which are passed as parts of an argument to a command?
I would like to use the Tensor package with LyX. The problem is that LyX always puts subscripts ...
- 329
5
votes
1
answer
133
views
Why does a \catcode-changed underscore work in math mode also without \mathcode set to "8000?
Something is puzzling me... consider
%\begingroup
%\catcode`\_=13
%\gdef_{\sb}
%\endgroup
\catcode`\_=11
\def\foo_bar{Foo bar}
\foo_bar\ $a_b$
\bye
Uncommenting the commented code yields
(One can ...
- 32.6k
9
votes
7
answers
592
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Detect catcode of next character?
I use only lualatex, but I suspect this is a general question, having something to do with core TeX.
Is there such a thing as \ifnextcatcode ? Pseudo-code:
\def\wanted{\ifnextcatcode{12}{\dothis}{\...
user287367
2
votes
0
answers
35
views
How can I get exactly one space in .idx? I know how to get two or none, but not just one
Consider the following MWE:
\documentclass{ltxdoc}
\makeatletter
\newcommand*\myindex[3]{%
\doc@providetarget
\index{#1:\levelchar#2\actualchar{\ttfamily#3}\doc@handleencap{usage}}%
}
\...
- 211k
2
votes
2
answers
72
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Compute depth without using any macro
For a library robust-externalize, write in a new file something like:
\newsavebox\boxRobExt%
\savebox{\boxRobExt}{%
my content
}%
\usebox{\boxRobExt}%
% some code to write `\the\dp\boxRobExt` into ...
- 9,116
1
vote
0
answers
259
views
Middle point in ConTeXt
In French, we sometimes use the middle point "·" as a way to write gender-neutral names (in the same spirit as the use of they/them pronouns in English), e.g : "Bonjour à tou·te·s"....
- 1,235
9
votes
1
answer
357
views
Why can the name of a `MathOperator` have a number?
This does not compile, which is what I'd expect:
\documentclass{amsart}
\newcommand{\G2}{G_2}
%\DeclareMathOperator{\G2}{G_2}
\begin{document}
\(\G2\)
\end{document}
produces
! LaTeX Error: Missing \...
- 1,468
1
vote
1
answer
171
views
Resolving tikzcd/externalize/align incompatibilities
I've been trying to follow the insights from the following posts:
Are the TikZ libraries cd and external incompatible with one another?
How to avoid redefining ampersand & globally?
Use & ...
- 343
0
votes
1
answer
44
views
Prevent active character from being expanded in macro argument
Goal: Have an active character not expanded when writing to file
MWE
\documentclass{article}
\makeatletter
% == Package code -- untouchable
\def\foo{\@ifnextchar[{\@foo}{\@foo[x]}}
\...
- 15
3
votes
1
answer
297
views
Using a command to generate a table row in tabularray
I have a command that generates a table row for insertion into a tblr environment as shown below:
\documentclass{book}
\usepackage{tabularray}
\begin{document}
\newcommand\MyRow[2]{
#1 & #2 \\...
- 133
1
vote
1
answer
86
views
what is definition of "\@nobreaktrue"? [duplicate]
I find it difficult to find the definition of commands starting with @. Where and how is \@nobreaktrue defined?
- 67
1
vote
2
answers
78
views
How to use catcodes in a macro/environment
I want to use catcodes in an environment and the catcodes shall be changed for a very short part in the document.
MnWE:
\documentclass[a5paper, 11pt]{scrartcl}
\usepackage{environ}
\NewEnviron{Lied}[...
- 2,348
1
vote
3
answers
160
views
LaTeX macro for topic sentences (square bracket "[" and "]" active character catcode)
When writing a document, I usually write "topic sentences" (i.e. outline sentences) between square brackets like so:
[in here is the main idea of the next paragraph]
Here I write a polished ...
- 13
1
vote
1
answer
86
views
12 catcode for UNDERSCORE and character printed
Does a LaTeX3 version of the following code could be simpler? I understand the logic, but I dislike the code...
\documentclass[12pt]{article}
\usepackage{color}
% Source: https://tex.stackexchange....
- 13.4k
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1
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67
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Spacing between \cdots and binary operators
I use \cdots to denote omitted terms in my sum, and expect it to have the same amount of spacing around it as if it were a usual term. Yet things are working a little differently from what I expect. ...
- 115
1
vote
2
answers
95
views
LuaTeX change the catcode of numbers
I'm trying to check if a label is defined with \ifdefine \r@labelname.
The label is a hexadecimal number like 215Bh and this does not work.
So I tried to change the catcodes of the numbers to 11
But I'...
- 13
0
votes
2
answers
154
views
How to print a vertical bar if it is \active?
I'm trying to print a vertical bar symbol, but it's \active in the ltxdoc document style (this code doesn't compile):
\documentclass{ltxdoc}
\begin{document}
This is a vertical bar: |\||
\end{document}...
- 12.3k
5
votes
4
answers
360
views
strlen in TeX Language
Trying to implement a simple algorithms in TeX language, I've tried to implement a string length function (potentially a token counter function). I know spacing in TeX engine has a different mean from ...
- 985
3
votes
2
answers
240
views
How to check whether some \catcode is \active?
I'm going to change a catcode to active and then implement my own formatting of small verbs:
\if-not-active
\catcode`|=\active
\def|#1|{\foo{#1}}
\fi
I want to make this non-intrusive and check ...
- 12.3k
4
votes
2
answers
239
views
Understanding this example of modifying category code
There was a question about automatically adding space after the periods and commas. An answer to it included modifying category code. It is shown below.
\documentclass{article}
\usepackage{expl3}
\...
- 891
1
vote
1
answer
47
views
Detecting if an argument to a macro is just a string
Let's say I construct a macro like \keywords{this, that, other} that accepts an argument, but I want to reject any argument that contains macros or anything besides space, newline, and characters (...
- 159
0
votes
1
answer
119
views
Defining unicode character in the context of another (pdfLaTeX)
This is a bit of a strange question.
Suppose for some unknown reason I want the character ɲ (U+0272, 0xc9 0xb2) to say "bye", the character ɳ (U+0273, 0xc9 0xb3) to say "aww", and ...
- 15
0
votes
1
answer
81
views
How to revert the effect of \obeylines and \obeyspaces for \input content?
This is my file a.tex:
\begin{tikzpicture}
\node[] (v) {hi};
\end{tikzpicture}
\endinput
This is main.tex:
\documentclass{article}
\usepackage{tikz}
\NewDocumentEnvironment{foo}{b}{
% here I ...
- 12.3k
3
votes
1
answer
114
views
How to redefine symbols inside my custom environment?
I'm trying to create my own foo environment, which would be used like this:
\documentclass{article}
\begin{document}
\begin{foo}
a -> b [
c => d ]
\end{foo}
\end{document}
I'm expecting it to ...
- 12.3k
0
votes
2
answers
192
views
Using hyphen as a letter in command names
I am using hyphen as a letter for command names. But I allow users to rename them if necessary. Then use \catcode`-=11. Suppose I keep the hyphen as a letter in command names, I wonder if users ...
- 1
2
votes
2
answers
72
views
How to define a new character while avoiding clashes with existing character definitions?
I want to define a new character. For context, in particular, my new character would act similar to the ^ character for superscripts, but would put parentheses around the context of the superscript.
...
- 121
5
votes
2
answers
186
views
First character of \ref{<label>}
Practically, I would like to decide if a reference to a label begins 1 or not.
The question has some relevance in Hungarian.
The idea was to use xstring package:
\documentclass{article}
\usepackage{...
- 115
8
votes
5
answers
579
views
Use : colon character in weird argument — expl3
Since \ExplSyntaxOn changes catcode of : it makes command with weird argument break when using the macro outside.
\documentclass{article}
\begin{document}
\ExplSyntaxOn
\cs_set:Npn \my_foo:w #1:#2\...
- 4,652
0
votes
2
answers
78
views
Change the font of apostrophe inside a command
I can universally change the font of apostrophe ' using
\def\myprime{{\usefont{T1}{ppl}{m}{n}\symbol{39}}}
\catcode`'=\active
\def'{\myprime}
But, what I really wanna do is to change it only inside a ...
- 925
1
vote
2
answers
127
views
Is it possible to redefine the character code of space?
If I execute the code \tt\catcode` =12\relax test
I get:
I also can emulate the same effect using \char32 in place of <space>. Is it possible to change the character code of <space>, so ...
- 680
4
votes
3
answers
239
views
How would I define a character to start and end an environment in plain TeX?
In TeX, starting and ending math mode is done with the same symbol, namely $. Suppose I would like to start and end an environment like this, perhaps with the text italic, using the character *, as ...
- 680
6
votes
3
answers
745
views
How to use \catcode in a command?
I would like to define the character @ as follows:
\def @#1#2{\catcode`#1=13\def #1{#2}}
so that when I type @xy x, TeX typesets y. However, when I run this, I get an error.
I have seen other answers ...
- 680
3
votes
1
answer
240
views
pdflatex stops when both german and hungarian languages are set in babel
This is a MWE:
\documentclass{article}
\usepackage[T1]{fontenc}
\usepackage[utf8]{inputenc}
\usepackage[german,hungarian]{babel}
\begin{document}
babel test
\end{document}
When I run pdflatex on ...
- 869
6
votes
1
answer
344
views
Why is the underscore OK inside of a `\cite` command?
The underscore character _ has a category code of 8, because it has special meaning in TeX and a special role.
Including an underscore in the main body of a LaTeX document will generally cause a ...
- 1,594