Add a custom latex command to be used with pandoc/markdown

Question

so I am using the popular Eisvogel template for my personal work. I basically type everything in markdown and use pandoc to convert it to a pretty pdf.

Using blockquotes ( > text ) results in a pretty bar. However I came across the desire to add more options of styles. Let's say I do not only want to use these block quotes for real quotes, but also for "information panels" or "alert panels". I'd love to have the option to somehow give a prefix or custom-tex command within my markdown file and have the proper box being displayed.

Lets say rather than having: > text which results in a good looking, grey box, with a dash on the left side, I'd like to have something like \alert > text so the box is being rendered in some red, rather than the original blockquote colour.

Sure, the syntax could look totally different, but I just need to find a way to customize this cool pandoc-latex stuff a bit more, preferrably with custom commands. I am a bit familiar with writing pure LaTeX, but using pandoc just goes way faster, since I am also taking notes within my markdown files.

Anyone got an idea?

cheers

Answer 1

Well, looking at the eisvogel template, it looks like it typesets blockquotes inside a special customblockquote environment defined using the mdframed package: see its documentation.

You can define new LaTeX commands for use with pandoc with a header-includes: yaml option. (Or in a separate file included with the -H command line flag.) One option I suppose would be to use such a command to redefine this environment. You'd have to redefine it back to the way the template defines it if you wanted to go back to normal

---
title: My Document
author: Someone
date: 7 May 2022
header-includes: |
    \definecolor{myred}{RGB}{245,20,20}
    \newcommand{\normalquote}{
        \definecolor{blockquote-text}{RGB}{119,119,119}
        \renewmdenv[rightline=false,
            bottomline=false,
            topline=false,
            linewidth=3pt,
            linecolor=blockquote-border,
            skipabove=\parskip]{customblockquote}
    }
    \newcommand{\redalert}{
        \definecolor{blockquote-text}{RGB}{240,240,240}
        \renewmdenv[
            linewidth=2pt,
            linecolor=black,
            leftmargin=10pt,
            rightmargin=10pt,
            backgroundcolor=myred,
            fontcolor=white,
            shadow=true,
            skipabove=\parskip]{customblockquote}
    }

...

This is some regular text.


> This is a regular quote.

\redalert
> This is a *very* red box with a shadow and light text.

\normalquote
> This is a normal blockquote again.

You could of course define as many such styles as you wanted.

Most likely if I knew more about pandoc filters and templates, there would be a more straightforward way, but this may work well enough for your purposes.

Answer 2

Consider switch to quarto, that aim to be an evolutionary leap of R markdown. Maybe this is not a good idea if you are hooked to a custom template (I am not tested if it could be used asis in quarto, after some/many changes or not used at all), but otherwise quarto include some easy to use predefined "callouts":

---

The source (mwe.qmd):

---
format: pdf
---

## Callouts in Quarto

In Quarto (next generation of R markdown) you can use "callouts" 
to show predefined alert boxes. For PDF output, \LaTeX\   
`tcolorbox` package is used in the background automatically.


::: callout-note

There are five types of callouts: 
`note`, `tip`, `warning`, `caution` and   `important`. 

:::

::: callout-tip
## Tip with custom caption

This is an example of a tip with custom caption.

:::
    
::: callout-warning
foo
:::

::: {.callout-caution}
## Take care !  

foo

:::

::: callout-important
foo
:::

Note that in the "classical" R markdown you can use also custom blocks to produce different LaTeX environments. For instance, a simple tcolorbox could be:

::: {.tcolorbox data-latex="[title=Warning]"}
foo 
:::

But as you see, the syntax is a bit more complex even for a default box, and you are in charge of include the packages needed in the template, or the header-includes or so, and make more elaborate boxes will need some extra work (see the link), while in Quarto is just type the simple callout blocks. Moreover, these blocks cannot be exported to another formats, while Quarto's callouts are exported to HTML and DOCX tables that mimic very well the tcolorboxes.

Answer 3

Since the discussion seems to be leaning towards admonition blocks, I would suggest taking a look at Awesome Boxes:

https://www.nic.funet.fi/pub/TeX/CTAN/graphics/awesomebox/awesomebox.pdf

Easy to use, plays well with markdown and pandoc.