Dynamic routes

The bracketed filename becomes the capture name. args.slug is the captured string for that request. Empty captures (for example /blog/) miss this route and fall through to a 404.

# pages/blog/[slug].rat
> server
title: 'Blog post'

> page
<h1> [args.slug]
<p> URL was /blog/[args.slug]

Bracket-folders can sit anywhere in the path. Static segments must match literally; bracket segments capture and bind. Multiple captures stack into args by name.

pages/users/[id]/posts/[post_id].rat
# matches /users/42/posts/hello
# args.id == '42'
# args.post_id == 'hello'

Each capture is also bound at the top level of the scope under its name. [slug] and [args.slug] resolve to the same value, so use whichever reads better at the call site.

# pages/blog/[slug].rat
> server
post: main_db.post.first({slug: slug})

> page
<h1> [post.title]