How can I change the default PDF output of #| code-fold: true?

[elenlefoll]

Description

I have written a textbook that I want to render to both HTML and PDF. The HTML version contains some folded code chunks, which means that readers of the HTML version have the option of clicking to view the code underlying a figure, for example (see example Quarto doc below).

When I render to PDF (see attachment), the code folds are ignored and the code is printed regardless of whether I specified code-fold: true or not. I would like the default to be the other way around: if a folded code chunk is rendered to PDF then the code should not be printed. How can I achieve this?

---
title: "Code-fold default in PDF"
date: last-modified
author: Elen Le Foll
format: pdf
---

```{r}
#| label: demo-chunk
#| code-fold: true
#| code-summary: "See `R` code to generate plot."

plot(1:10)
```

reprex.pdf

[mcanouil]

How do you want the code to fold in static formats?

What do you actually want to do? echo: false?

Side note: avoid writing your request/question as part of the reproducible example, it makes reading harder because your actual question is hidden. It's also less accessible, because your question is now "code" and not prose.

[mcanouil]

There are many ways to have echo: false for PDF (LaTeX):

• using knitr !expr syntax in echo.
• using conditional contents.
• using Lua filters.

[mcanouil]

You can "reuse" your div with The following Quarto extension:

• https://github.com/mcanouil/quarto-div-reuse

[elenlefoll]

I was rather hoping there might be a way to change the current default of:

• if code-fold: true, then code is displayed in full in LaTex
  to:
• if code-fold: true, then code is not displayed in LaTex for an entire book project.

[mcanouil]

There are no default to change. code-fold is HTML details/summary. This does not exist outside HTML-based formats thus why it's "ignored".

• https://quarto.org/docs/output-formats/html-code.html#folding-code

Soo you have to use any approaches mentioned before.

---
format: pdf
---

```{r}
#| label: content
#| code-fold: true
#| code-summary: "See the code"
#| echo: !expr "knitr::is_html_output()"
print("Hello, world!")
```

or

---
format: pdf
filters:                                                                                                                                                                                                 
  - path: code-fold-latex.lua
    at: pre-quarto
---

```{r}
#| label: content
#| code-fold: true
#| code-summary: "See the code"
print("Hello, world!")
```

if not quarto.doc.is_format("latex") then return {} end

return { {
  CodeBlock = function(el)
    if el.attributes["code-fold"] then return {} end
  end
} }

[elenlefoll]

Thanks a lot for your answers. I'll see which of these options works best for my project!