Questions tagged [programming]
{programming} is about how (La)TeX can be used as a programming language.
670 questions
5
votes
1
answer
144
views
Mapping structure in LaTeX3
I'm developing a LaTeX class for typesetting theses at the University of Trento, aiming to streamline every aspect of the thesis formatting process.
One feature I want to implement is allowing ...
- 731
0
votes
1
answer
53
views
Unecessary checks before calling `\cs_if_exist_use:cTF`?
Consider this wrapper as an example:
\prg_new_conditional:Nnn \check_engine:n{p,T,F,TF}{
\tl_trim_spaces_apply:nN{#1}\__check_engine:n
}
\cs_new:Npn \__check_engine:n #1{
\bool_lazy_any:nTF{
...
- 5,801
1
vote
0
answers
60
views
Problem with conditional: TF version working, but not the p version
I reused the code provided as an answer here (I tried to make it a new conditional)
\prg_new_conditional:Npnn \if_font_exist:nnnn #1#2#3#4{p,T,F,TF}{
\group_begin:
\tl_if_empty:nF{#1}{\...
- 5,801
2
votes
1
answer
96
views
tl_trim_spaces and tl_if_blank?
Is there any input for which, once processed with tl_trim_spaces could lead to tl_if_blank being true AND tl_if_empty being false?
- 5,801
1
vote
2
answers
146
views
LaTeX3 version of expandafter-ifx-csname?
I currently have this code from a previous question (link here)
\NewDocumentCommand \IfFontTF {mmmmmm}
{%
\begingroup
\fontencoding{#1}\fontfamily{#2}\fontseries{#3}\fontshape{#4}\try@load@...
- 5,801
2
votes
2
answers
91
views
What does \token_if_expandable:N(TF) actually test?
In LaTeX3 am wondering what \token_if_expandable:N(TF) actually test? The documentation says:
Tests if the ⟨token⟩ is expandable. This test returns ⟨false⟩ for an
undefined token.
but I am guessing ...
- 5,801
0
votes
2
answers
68
views
Understanding expansion patterns related to \exp_args:Ne
I have read tens of pages on expansion, and for whatever reason, I am still missing a clear understanding. To help me understand, I would like to focus on a specific example.
Consider the following ...
- 5,801
5
votes
4
answers
334
views
How to check if a font exists with pdflatex?
When using XeTeX or LuaTex and fontspec, one can use \IfFontExistsTF{font name}{yes code}{no code}. What would be the best way to test if a font exists/can be loaded when fontspec is not available (...
- 5,801
1
vote
1
answer
94
views
Check if an input is a dim or a skip/muskip in an expandable way?
I am wondering how to create efficient expandable functions in LaTeX3:
\check_if_dim:n
\check_if_skip:n
\check_if_muskip:n
that would check if an argument can be parsed as a dimension, a skip or a ...
- 5,801
2
votes
1
answer
87
views
What is the role of \tl_to_str:n versus using directly the functions from the l3str module?
Let's say I am creating an expl3 macro:
\cs_new:Nn \my_function:n{
% Something
}
I have hard time understanding the exact role of \tl_to_str when processing the argument compared to "just&...
- 5,801
2
votes
1
answer
93
views
Efficiently checking if an input can be parsed as a floating-point number in an expandable way in LaTex3?
I am trying to implement a function in LaTeX3 \check_if_fp:n that checks if an input can be parsed as a floating-point number (in an expandable way, so not using regexes). After a lot of thinking I ...
- 5,801
0
votes
1
answer
41
views
Macro to change babel's caption for pre-defined sections for any language
So I came up with this handy little macro that in principle can change any pre-defined babel spanish caption:
\newcommand{\spacaptchange}[2]%
{
\addto\captionsspanish%
{
\renewcommand*{...
2
votes
2
answers
328
views
Implementing MATLAB code in LuaLaTeX
First of all I am aware of the complexity involved in the following question, but I wonder if something similar has been already solved (maybe even partially) by someone, who was interested in this ...
- 228
3
votes
2
answers
86
views
Using plural for appendix if more than one
Consider the following code, which adds the plural word appendices rather than appendix, if there is more than one appendix. I have added Babel and German, just for testing and a google translation ...
- 119k
4
votes
3
answers
207
views
Expansion in Latex3 when transforming an input and forwarding it to another function
There are still a lot of mystery around expansion in LaTeX for me, but even given that, there is something I don't understand in LaTeX3. Let's say (just for the example), that I want to test whether ...
- 5,801
0
votes
4
answers
102
views
How to detect inner spaces at the document level forwarded to token lists in LaTeX3?
Unprotected spaces are not treated as items in token lists in LaTeX3. If I have some argument coming from the document/user level, and I would like to detect if this argument have an inner protected ...
- 5,801
0
votes
2
answers
48
views
Check if a predicate is satisfied on all tokens in LateX3 using conditionals
I am trying to write an expandable conditional that test if a condition is satisfied and it does not seem to work as expected.
Currently here is my approach (with \token_if_letter_p as an example of a ...
- 5,801
6
votes
1
answer
163
views
Long and protected macros in LaTeX3
I have questions about the following functions in LaTeX3:
\token_if_macro_p:N
\token_if_long_macro_p:N
\token_if_protected_macro_p:N
\token_if_protected_long_macro_p:N
How do they behave with the ...
- 5,801
3
votes
3
answers
317
views
Testing if a string is a hexadecimal string in LaTeX3: code review, optimization, expandability, and protection
Consider the code in LaTeX3. It tests whether a string is a hexadecimal string (optionally also testing the length of that string) (a string where every character is either 0-9 or A-F).
\documentclass[...
- 5,801
0
votes
0
answers
65
views
Fast way to test if an argument is a HTML color-code in LaTeX3?
I recently asked how to test if an argument is an integer using LaTeX3 (here). I am wondering how to use the same approach to test if a string correspond to a HTML color-code. Currently, I use the ...
- 5,801
3
votes
1
answer
106
views
Branching on whether a color is defined using xcolor or xcolor-material?
I am trying to branch on whether a color (defined in xcolor or xcolor-material or using the utilities provided by these packages) has a name that can be used in the \color command (from the xcolor ...
- 5,801
0
votes
2
answers
71
views
Splitting and forwarding to bool_lazy_any in LaTeX3?
I currently have a function which does the following:
\NewDocumentCommand{\myfunction}{m m m}{
\str_if_eq:eeTF{\c_sys_engine_str}{#1}{#2}{#3}
}
which allows me to do something as: \myfunction{...
- 5,801
2
votes
2
answers
145
views
Build a new command "newsymbol" with NewDocumentCommand
I want to create a new command \newsymbol, which functions like \newcommand, but with the difference that math is ensured. I also have another reason, why I want to define this new command, namely so ...
- 1,832
4
votes
1
answer
132
views
Why \IfPackageAtLeastTF{⟨package⟩}{⟨date⟩}{\PassOptionsToPackage{⟨option⟩}{⟨package⟩}}{} doesn't pass ⟨option⟩ to ⟨package⟩?
My current version of parskip is 2021-03-14 so:
\IfPackageAtLeastTF{parskip}{2018-08-24}{\PassOptionsToPackage{indent}{parskip}}{}
\usepackage{parskip}
should pass the indent option to parskip. But ...
- 10.3k
0
votes
0
answers
25
views
How can I adjust the spacing between the number and the title of each level in TOC to create automatically a nested list?
In this code, I have defined custom sectioning formats using the titlesec package. However, I'm having trouble adjusting the spacing between the section numbers and titles, especially when the section ...
3
votes
2
answers
250
views
Best Practices for Integrating Computer Algebra Systems (CAS) into LaTeX Documents
I am currently working on enhancing my LaTeX documents to involve complex mathematical equations. Managing these equations manually often leads to errors, especially when changing dependent equations ...
- 1,215
2
votes
1
answer
59
views
How to trim spaces without expanding what is inside in expl3?
Consider the following pattern:
\NewDocumentCommand{\mycommand}{m}{
\myinternalcommand:n{#1}
}
\cs_new:Nn \myinternalcommand:n{
\tl_if_single:nTF{#1}{TRUE}{FALSE}
}
and let's say that I want ...
- 5,801
3
votes
1
answer
158
views
LaTeX3 regex not working
I have a very strange bug and I guess I am not using LaTeX3 regexes as they are supposed to be used. My current document looks like this:
\documentclass{standalone}
\ExplSyntaxOn
\regex_new:N{\...
- 5,801
1
vote
3
answers
69
views
In Latex3, how to test if all tokens in the input verify a test (for example \token_if_letter or \token_if_space)?
In Latex3, I would like to write a function that checks if every token of an input verify a predicate.
Basically I would like the multitoken version of this command:
\NewDocumentCommand{\mychecksingle}...
- 5,801
6
votes
2
answers
372
views
if_exist macros in LaTeX 3: what are they doing if they do not check the type of things they are supposed to check?
In the documentation of interface3, for several macros with the pattern xxxx_if_exist for xxxx being bool, str, seq and many others the following appear:
Tests whether the <boolean> is ...
- 5,801
1
vote
1
answer
241
views
Is LaTeX a programming framework of TeX?
My take from What is the difference between TeX and LaTeX? is that TeX is the programming language that renders the document. LaTeX is a well-known macro package for TeX with the aim to make the ...
- 1,550
3
votes
3
answers
668
views
Put many images into multiple pages programmatically
I have many images, for example
image01.jpg
image02.jpg
...
image80.jpg
I want to put those images into a document, 8 images per page, 4 rows and 2 columns (assume they will fit into one page that ...
- 137
10
votes
1
answer
417
views
Moving from pgfkeys to latex3 key-val system to handle package options
I have been advised in this question to move from pgfopts to latex3 to handle package options. I would like to do that but I must admit that I am a little lost. Examples with the patterns I'm using ...
- 5,801
4
votes
2
answers
109
views
Difference betwen .is family and .cd in pgfkeys in the context of package writing?
I am using pgfopts to create my own packages and handle options. .family and .cd can be used to group the package options together, but I am not sure to understand the pros and cons of each approach, ...
- 5,801
5
votes
3
answers
241
views
Counting the number of occurences of specific characters in a string in an expandable way
This question shows how to count the number of occurrences of a specific character in a string. I would like to do it in an expandable way, and for a list (not only one) of specific characters.
\...
- 5,801
0
votes
0
answers
105
views
Detect if something is a length?
Is there a way in LaTeX to detect if something is a length with a function of the form:
\NewDocumentCommand\iflength{m m m}{%CODE HERE%}
where:
the first parameter is the thing to be tested
the ...
- 5,801
0
votes
2
answers
129
views
A macro to check command expandability
I would like to create a command that checks whether an expression is fully expandable, and crashes if not (ideally printing an error message). I would like to do that without a specific TeX engine in ...
- 5,801
0
votes
1
answer
68
views
Branch to something when an expression cannot be evaluated by fpeval
I would like to design a \comparator expandable command that relies on fpeval that has 3 branches:
true branch when the comparison is equal to 1
false branch when the comparison is equal to zero
...
- 5,801
0
votes
1
answer
99
views
In expl3, how to test if something, once fully expanded, contains any character belonging to classes 11 or 12?
I am wondering in expl3 syntax (not using the most recent additions, let's say additions posteriors to 2018 [nothing special about 2018, it's just an arbitrary date to say not too recent]) how to test ...
- 5,801
1
vote
0
answers
103
views
Design a generic numeric comparator function using expl3 working for strings, counters, numexpr, dimexpr
I would like to design a generic compare function between numbers, ideally expandable with the following signature:
\NewExpandableDocumentCommand{\compare}{r[] m m m m m}{%CODE HERE%}
that would be ...
- 5,801
4
votes
3
answers
150
views
Problem with a command that prefixes words only if needed when the arguments are provided through macros
Consider the following code coming from this answer, where it adds a prefix to a word, only if the prefix is missing.
\documentclass[border=6pt,varwidth]{standalone}
\ExplSyntaxOn
\...
- 5,801
5
votes
4
answers
330
views
An expandable command that adds a string to an argument if the string is missing
I would like to write and expandable command which adds a string S1 at the beginning of another string S2 if S2 does not start with S1 in order to ensure that my string always start by S1.
I currently ...
- 5,801
1
vote
2
answers
80
views
Macros to change pgfkeys package options on the fly and define custom sets of options
Consider the following code for a package :
% Preamble
\NeedsTeXFormat{LaTeX2e}[1994/06/01]
\ProvidesPackage{mypackage}[2024/01/01 MyPackage]
\makeatletter
% Dependencies
\RequirePackage{pgfopts}
\...
- 5,801
1
vote
1
answer
39
views
Command color not working with the name of a color built through macros
Consider the following code and especially the command \nicecolorname which builds the name of a color following the pattern ["nice"][shade][hue]. In its current name, the command \color is ...
- 5,801
3
votes
1
answer
64
views
ifmtarg testing a macro that is empty?
The following code works as expected:
\NewDocumentCommand{\checker}{m}{\@ifmtarg{#1}{empty}{not empty}}
\checker{} % Prints "empty"
\checker{x} % Prints "not empty"
However, how ...
- 5,801
3
votes
1
answer
139
views
Parse every character and transform it into a table column
I am trying to produce an array that will output most ascii characters in a given LaTex font. Currently, I have the following awful code that works:
\documentclass{standalone}
\usepackage[utf8]{...
- 5,801
31
votes
4
answers
18k
views
LaTeX v.s. Typst: What is TeX Community's Future Plan? [closed]
Recently I have become increasingly anxious about LaTeX being (possibly) surpassed by Typst due to its simplicity. This answer shows several edges of Typst over LaTeX.
I have been arguing with one of ...
- 2,280
2
votes
2
answers
86
views
LaTeX does not finish compiling (infinite loop, maybe) when I place multiple \tl_use commands inside the \bool_until_do loop
I am trying to retrieve data from a .aux file using expl3.
I want to ignore the first line because it serves a different purpose (hence the \ior_str_get:NN \l_seccion_lista_ior \l_tmpa_tl). The ...
- 538
5
votes
4
answers
556
views
how can I write an inline hexadecimal value? [duplicate]
How do I write an inline "\0x" without having LaTeX put each value on a new line?
"\0x" in C programing identifies a hexadecimal value. I would like to write an inline string of ...
- 171
0
votes
1
answer
242
views
Is there an alternative to using yap.exe for rendering dvi files within MikTeX?
I have used MiKTeX and the book document class for mathematics layout for more than 10 years with little trouble. The "build" command always runs successfully but, just recently, the "...
- 466