Support for inline math expressions

[p-gw]

Thank you for this great theme.

Since Katex shortcodes are already implemented I wondered whether inline math expressions are supported as well. I already tried the basic inline syntax using $$ (e.g. some text $$x = 1$$ some more text), but it gets rendered as a block.

It is suggested here to add markup: mmark to the front matter or to save the *.md files as *.mmark. When doing so the inline math expressions do get rendered correctly with $$ but the table of contents in the right column vanishes.

Is there a way to both get inline math as well as keep the table of contents when using hugo-book?

[alex-shpak]

Hi!
Unfortunately, I think mmark renderer doesn't support ToC listing.
Also it is about to be removed from Hugo https://gohugo.io/content-management/formats/

[BettyFabre]

Hi,
I faced this issue too and solved it by modifying the katex shortcode by :

{{ if not (.Page.Scratch.Get "katex") }}
<!-- Include katext only first time -->
<link rel="stylesheet" 
...
  onload="
      renderMathInElement(
          document.body,
          {
              delimiters: [
                  {left: '$$', right: '$$', display: true},
                  {left: '\\[', right: '\\]', display: true},
                  {left: '$', right: '$', display: false},
                  {left: '\\(', right: '\\)', display: false}
              ]
          }
      );"></script>
{{ .Page.Scratch.Set "katex" true }}
{{ end }}

<p class="katex{{ with .Get "class" }} {{ . }}{{ end }}">
  $$ {{ .Inner }} $$
</p>

it just changes the call of auto-rendering from Katex like in the KaTex repo

Then I created another shortcode (based of the katex one) for inline math that uses span & the $.$ syntax :

...
<span class="katex{{ with .Get "class" }} {{ . }}{{ end }}">
  ${{ .Inner }}$
</span>

Finally I can call this shortcode to generate inline math in a post like for example
a permutation {{< katex_inline >}}\pi(x){{< /katex_inline >}} and it works fine.

It may not be optimal but it can be a start.

[alex-shpak]

I updated KaTeX shortcode so that it accepts display param. So:
{{< katex >}}\pi(x){{< /katex >}} will produce \( ... \) wrap for inline text and
{{< katex display >}}\pi(x){{< /katex >}} will procude \[ ... \] wrap for display mode.

[alex-shpak]

This will work for now, but it have high chance to mess with markdown. For example if you put inline shortcode in the middle of heading (like ## heading <shortcode> rest of it) it will break markdown layout.

[p-gw]

Thank you @BetFab for the modification and @alex-shpak for the implementation! This will work just fine for my use case.

[alex-shpak]

👍 I will close this issue then, write here if you want me to reopen.