Prev / next links

Every content page knows its neighbors. The data is always there, no configuration, on page.nav:

#let page(page, body) = {
  body
  let nav = page.nav
  if nav.prev != none { link(nav.prev.url)[#nav.prev.title] }
  if nav.next != none { link(nav.next.url)[#nav.next.title] }
}

nav.prev and nav.next are each either none or a dict with the neighbor’s url and title.

Which neighbors

The order is the collection’s own sort and reverse, so a sort "date" reverse #true blog links newest to oldest while a sort "order" guide links chapter to chapter. Three things bound it:

• Navigation never crosses a collection boundary, and never crosses a language boundary on a multi-language site.
• Drafts, future-dated and expired pages that were filtered out are skipped, so a link only ever points at a page that was actually built.
• The 404 page is neither a neighbor nor given neighbors of its own.

Generated index and term pages have no siblings. Their prev/next is pagination, and it arrives as plain URLs on page.frontmatter.nav instead.

Labels

page.strings carries whatever the current language declared under languages { fr { strings } }, so a pager can label itself in the reader’s language. Nothing is declared by default, so read it with a fallback:

let back = page.strings.at("previous", default: "Previous")
if nav.prev != none { link(nav.prev.url)[#back] }

See multiple languages.

The whole site, in order

page.nav names two neighbors, deliberately. For the full ordered tree of content directories, a template imports @baudelaire/sections, which is what a sidebar is built from:

#import "@baudelaire/sections:0.1.0": sections

See Typst modules for its shape.