Nodes

Nodes are your own LowNodes that write Markdown into the file with replace, and render HTML into the page with render.

Put them in a .raindown folder beside your files, or in a folder above them, and Raindown loads them with Dirload:

# .raindown/changelog.rb
class Changelog < LowNode
  def initialize(limit: 5)
    @releases = Release.all.first(limit)
  end

  # Written into the Markdown.
  def replace
    @releases.map { |release| "- **#{release.version}** #{release.summary}" }.join("\n")
  end

  # Rendered into the HTML. Without it, the HTML of the Markdown above is rendered.
  def render
    "<section class=\"changelog\">...</section>"
  end
end

Node blocks

A node block names the node and its props, and Raindown writes the node's Markdown into it whenever the file is rendered:

<{ Changelog: limit=3 }>

- **1.2.0** Bare directives close themselves
- **1.1.0** Track fetched dates

<{ :Changelog }>

In a Raindown file it can also use bare syntax, with the Markdown straight below it up to the next blank line (a bare node block can't write blank new lines):

Changelog: limit=3
- **1.2.0** Bare directives close themselves
- **1.1.0** Track fetched dates

A self-closing <{ :Changelog }>, or a bare :Changelog, renders the node into the HTML without writing it into the file.

Props

Props can be quoted text, numbers, true, false or front matter keys like author.name, written limit=3 or limit: 3.

replace and render can also take the keywords document: (the Markdown being rendered), metadata: and bare:, and get the ones they ask for.

Lifecycle

Raindown keeps one instance of each node and its props while it runs, so replace and render can share what they work out, like the releases above.

A name only starts a node block when it's a loaded LowNode with a replace method, so other text like Note: is left alone.

Built-in nodes

Table of contents and files are nodes too, and a project can replace them with its own TOC or Files node.