Improve references when exporting to PDFs

[QuantumVictor]

Proposal

MyST Website ouptut

Currently, it is possible to link sections and chapters in MyST websites. In the example I provided, we have a simple book structure where we defined a chapter in a folder and sections in dedicated pages. With MyST Website, we are able to link any word to

• an other section : the Asia section refers to the Asia page in the example below,
• to a numbered subsection : we linked the Jaguar displaying the section number (1 here)
• to a non-numbered subsection : for example, I linked to the Lions section using [](#lion-section) and to the pandas one using [pandas](#panda-section).

We then generate the book using the plain_book template.

Default Latex output

The default output has several issues:

• the link between sections (different myst webpage) results in a hyperref non existing page,
• the non-numbered section have no links anymore,

I will first discuss animal coming from \href{/ch1-asia}{Asia} (go there 
to have information about pandas !). We will also detail animals 
from \href{/ch1-africa}{Africa}, especially Lions. We will then describe 
the  \href{/ch1-southamerica}{the South America region} with Jaguars 
in Section~\ref{jaguar-section}.

Proposed output latex

• MyST pages could be labeled either with a default label (page name) or by a frontmatter keyword label for example.
• we could take benefit of the hyperref package to link section in the pdf,

I will first discuss animal coming from \href{/ch1-asia}{Asia} (go there
to have information about \hyperref[panda-section]{pandas} !). We will
also detail animals from \href{/ch1-africa}{Africa}, especially 
\hyperref[lion-section]{Lions}. We will then describe the  
\href{/ch1-southamerica}{the South America region} with Jaguars 
in Section~\ref{jaguar-section}.

Files to repeat the example

index.md ch1_southamerica.md ch1_asia.md ch1_africa.md ch1_0intro.md

Table of content _toc.yml

format: jb-book
root: index
chapters:
  - file: ch1_0intro
    sections:
      - file: ch1_asia
      - file: ch1_africa
      - file: ch1_southamerica

Note : on the ch1_africa, I did not defined the title in the front matter but in the main document in order to add a cross-reference label but the \label{label-africa} in the tex document.

---
short_title: Africa
---
(label-africa)=
# Africa

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[rowanc1]

Thanks @QuantumVictor, this is also an issue for our typst export when there is a cross-reference outside of the current article (or articles) -- are you exporting a single page here, or a multi-article document?

[QuantumVictor]

Hi @rowanc1 , I just provided my MyST files of the example by re-editing the comment (sorry, I posted too early my issue...)