Book – keep both pdf and html outputs in _book directory

[baptiste]

I'm a bit stumped with this: I'm using quarto to write a book, with the following Yaml (simplified):

project:
  type: book
  output-dir: "_book"

execute:
  echo: false

book:
  title: "stuff"
  author: "baptiste"
  date: "21/10/2022"
  chapters:
    - "index.qmd"
    - "01-introduction.qmd"
    - "02-theory.qmd"
    - "03-applications.qmd"
    - "90-appendix.qmd"
    - "99-references.qmd"

bibliography: references.bib

format:
  html:
    theme: cosmo
    keep-md: true
  pdf:
    documentclass: krantz
    keep-md: true
    keep-tex: true

engine: knitr

For some reason, when I render to html, the previous pdf output is deleted, and the opposite happens when I render to html. How could I keep both outputs?

[cscheid]

We will need a full example to track down what's happening.

[baptiste]

I think it should work with any project, for example the skeleton from quarto create-project mybook --type book, as it appears to be because I was using

quarto render --to pdf
quarto render --to html

separately, as opposed to a single

quarto render 

It's a bit unintuitive that the previous output folder would be emptied when rendering to a specific format; is there a way to turn this off?

[cscheid]

I see, and I agree that's unfortunate. I believe the problem is specific to book formats, which always generate output inside a subdirectory, and the subdirectory has the same name across formats. As with other path issues in quarto, the fix won't be easy on our side, and I don't think there's an easy way to disable this.

On the other hand, a workaround should be relatively simple. If you truly must preserve the output, you could if [ -d _book ]; then mv _book $safe-place; done before calling quarto render.