Can you make callouts collapsable by default?

[malcolmbarrett]

You can make callout blocks collapsable by adding collapse="true" as in https://quarto.org/docs/authoring/callouts.html#markdown-syntax.

Can you make this the default for all callout blocks in a project, e.g. via the project YAML?

[shafayetShafee]

I am not sure there's a straightforward YAML option to do this, but I can offer a solution using Lua filter.

_quarto.yml

project:
  type: book
  
book:
  title: "Quarto Book"
  chapters:
    - index.qmd
    - callouts.qmd
  
format: html

callouts.qmd

---
filters: 
 - callouts.lua
---

# Callout Blocks

:::{.callout-note}
Note that there are five types of callouts, including:
`note`, `warning`, `important`, `tip`, and `caution`.
:::

:::{.callout-tip}
## Tip With Caption

This is an example of a callout with a caption.
:::

:::{.callout-caution}
## Expand To Learn About Collapse

This is an example of a 'folded' caution callout that can be expanded by the user. You can use `collapse="true"` to collapse it by default or `collapse="false"` to make a collapsible callout that is expanded by default.
:::

:::{.callout-important}

This is important
:::


:::{.callout-warning icon='false'}

WARNINGS !!!!
:::

callouts.lua

function Div(el)
  if quarto.doc.isFormat("html") then
    callouts = {'callout-tip', 'callout-note', 'callout-warning', 
              'callout-caution', 'callout-important'}
    for key, val in pairs(callouts) do
      if el.classes:includes(val) then
        el.attributes["collapse"] = 'true'
        return el
      end
    end
  end
end 

---

---

But I don't know how to add this lua filter to the project YAML file so that it applies all the qmd files.

[malcolmbarrett]

This worked great, thank you! All I needed to do was add the filters yaml to the top level of _quarto.yml

For anyone that's interested, here's what we did in practice: https://github.com/malcolmbarrett/causal-inference-in-R/pull/128/files#diff-469a07f57393912a9c17c3ea50ceebe991e32b008beb167a200b17e91fdac6d2

[cderv]

Just note that since Quarto 1.3, there are custom AST nodes, and Callout is one of them.

here is an example of the Lua filter to use to achieve this

• https://examples.quarto.pub/collapse-callout/

[haxfn]

ast seems awesome, i have zero skills in JS and zero hackability on web tech

[mcanouil]

@haxfn look for existing extensions then: https://m.canouil.dev/quarto-extensions/

This is available as one.

[haxfn]

Oh, I was able to use the lua code in the link shared by cderv.

I was just wondering if ast would make hacking around quarto with treating qmd files as structured data to be processed in code. I guess ast does indeed allow that?