plainleaf/website/Object/relation.md

Relation objects represent typed and untyped relationships between indexed Object in the space. They are the source of truth for relationship queries (graph views, backlinks of non-page objects, typed-attribute edges). The legacy Object/link collection is now a virtual projection over relation.

Attributes

• from: ref to the source object: the innermost indexed object that contains the markup producing the edge (page, item, nested item, or fenced #tag block object). When the source item carries a $anchor the anchor name is used (matching the item's own ref), otherwise the source's byte-offset form (page@pos) is used.
• fromTag: tag of the source object, denormalized for graph queries.
• to: ref to the target object.
• toTag: the target type — one of page, anchor, document, url. Set for every resolved edge (absent for unresolved refs). url is a built-in target tag, like document (a real object type) and anchor (a meta-tag).
• kind: the edge label. Either a reserved structural value — mention or co-mention — or a user predicate (e.g. spouse, team) taken from a frontmatter key, inline [key: ...] attribute, or #tag data block key. See #Kinds below.
• via: for co-mention entries only: ref to the containing item or paragraph that scopes the co-occurrence.
• page: page where the edge was discovered (used for invalidation).
• range: [start, end] byte offsets of the wikilink / markdown-link / attribute-value syntax within page. Always present. For co-mention records (which are derived) this points at the source-side wikilink. Used by the rename refactor to splice text.
• alias: when the source form is [[ref|alias]], the alias. Required to faithfully reproduce the link on rewrite.
• snippet: contextual text around the edge where available.
• pageLastModified: last-modified timestamp of the source page, useful for ordering.

Kinds

• mention: a plain wikilink or markdown link (to a page, file, anchor, or external URL — see toTag).
• co-mention: two refs co-occurring in the same item (with its nested children) or paragraph. Emitted in both directions and dedup'd at the innermost shared scope.
• user predicates: any other kind value is a typed attribute edge whose label is the key (e.g. spouse). from/fromTag indicate whether it came from frontmatter, an inline attribute, or a data block.

Examples

Here’s a tagged item to use as an example:

• #contact $pete-ref Pete [spouse: "Angela"] [team: "Super Team"]

Show every relation related to $pete-ref (including this one 👈):

${query[[ from r = index.relations() where r.from == "pete-ref" or r.to == "pete-ref" select table.select(r, "from", "fromTag", "kind", "to", "toTag") ]]}

All relations defined on this page: ${query[[ from r = index.relations() where r.page == "Object/relation" select table.select(r, "from", "fromTag", "kind", "to", "toTag", "snippet") ]]}