erynwells.me/layouts/shortcodes/figures/railroad.html

{{ $id := .Get "id" }}
{{ .Page.Scratch.Set "includes_railroad_diagram" true }}
{{ if not (in (.Page.Scratch.Get "railroad_diagram_ids") $id) }}
{{ .Page.Scratch.Add "railroad_diagram_ids" (slice $id) }}
<div class="centered">
    <figure class="railroad-diagram" {{ if $id }}id="{{ $id }}"{{ end }}></figure>
</div>
{{ end }}
<script defer type="module">
    import { railroadDiagram } from {{ `/scripts/railroad-utils.js` | relURL }};
    const className = {{ with .Get "class" }}{{ . | string }}{{ else }}undefined{{ end }};
    railroadDiagram(rr => {
        {{ .Inner | safeJS }}
    }, "{{ $id }}", className);
</script>