Is there any way to specify a latex template-partial file using a variable?

[eeholmes]

I am including a subfile within a latex template partial. I would like to choose the subfile based on a variable in the qmd document YAML. Like so:

Pertinent part of the qmd YAML where I have added the variable tpg-theme.

format: 
  pdf: 
    tpg-theme: abc
    template-partial: ["before-body.tex"]

Then in the latex template partial before-body.tex, I would have

$_$tpg-theme$.tex()$

This unfortunately does not work. Does anyone know of a way to dynamically (using a variable in the doc YAML) specify the subfile that is included in a template partial?

BTW here is what does work:

format: 
  pdf: 
    template-partial: 
        - "before-body.tex"
        - "_abc.tex"

Then in before-body.tex, I would have

$_abc.tex()$

Why don't I just do this? Because I can't change before-body.tex. It is set by my extension code.

Any solution that achieve this effect would work. I am not wedded to $_$tpg-theme$.tex()$. Other solutions I have thought of

• Being able to specify a subdirectory $tpg-theme$ where a file called _includedfile.tex is found. Then before-body.tex would be something like

partial.searchpath = $tpg-theme$
$ _includefile.tex()$

• A lua filter that copies $tpg-theme$.tex to _includedfile.tex. Then before-body.tex would be

$ _includefile.tex()$

I have no idea how to do that though.

[mcanouil]

I played a bit with your repository especially 'vline' and 'great-wave' (some issues with that one) to see how to answer your question.

In my understanding of Pandoc template, it is not possible to have partial LaTeX file paths dynamically set from yaml header.

Regarding a Lua filter, it might be the solution, but I do not know when it is applied exactly in Quarto's workflow.
I suspect, it is applied too late, i.e., here the filter is supposed to do some file pre-processing.

In your case, I would go for several subdirectories for each format and wait for #1836

[eeholmes]

@mcanouil Can you describe the issues with great-wave? I had a file name issue that caused it not to run on linux but I fixed that on Saturday. Someone else posted that they got an error re "no abstract" environment, which is odd since there is no \abstract in the LaTeX code.

I have a version running here
https://rstudio.cloud/content/4370280

[mcanouil]

I did an early fork in the weekend, I'll double check later this week.

[cderv]

Just another approach that may be considered.

Pandoc's template are quite simple in their logic as you can't really do complex if condition. But you could do something like

$if(tpg-theme-abc)$
$_abc.tex()$
$elseif(tpg-theme-cde)$
$_cde.tex()$
$else$
$_theme-default.tex()$
$endif$

Then in your document YAML, you could use tpg-theme-abc: true or tpg-theme-cde: true to activated one of the template.
Probably with a Lua filter, you could offer support for

tpg-theme: abc

by transforming to the correct variable for the template.

Maybe this is not possible because you said

I can't change before-body.tex. It is set by my extension code.

But I am not sure what is inside your partials...

Anyway, just sharing in case it helps

[mcanouil]

Thanks!
That was the next thing I was going to try, but this will give a structure less clear for the maintainer (or anyone else).

[dragonstyle]

Yeah agree it is kind of a bummer - I can't really think of a better way, sadly.

[eeholmes]

@mcanouil I have used paths as does quarto-journals. Just need to add to the template-partials: . But it is a little weird:

YAML:

template-partials: templates/before-body.tex

Template

$before-body.tex()$

So no subdir there. So yeah, weird.

[mcanouil]

I managed to make it work with all files at root.
Although, "great-wave" does not work well for some reason right now (no background image).
https://github.com/mcanouil/quarto_titlepages/tree/multi-formats-extension
@eeholmes If you want I can PR to your "extension" branch.

[eeholmes]

Yes go ahead and PR to extension branch. I had not tested that branch yet so prob broken in a few ways.

I was still unsatisfied with lack of theme or subdirectory soln. Having so many extensions folders for each title page design felt very meh.

On vacation for next week and will dive in again when I am back.