12 — RhoeMarkdown Matter, Carriers, and Structural Directives¶

Status¶

Normative baseline
Version: 0.9.0
Layer: Part 1 / Author Surfaces

1. Purpose¶

This chapter defines the universal rhoemd directives for matter and structure, plus the general rules for carrier-native directives.

2. Head Metadata vs Body Matter¶

YAML head frontmatter is root metadata only.
It is not the same thing as matter.frontMatter.
Body matter directives serialize the canonical MatterEnvelope.
Canonical examples in this chapter are full-valid artifacts unless explicitly marked as fragments.

3. Canonical Matter Directives¶

:::front-matter
:::main-matter
:::back-matter

3.1 Canonical authoring rule¶

Canonical authored sources SHOULD include all three matter directives explicitly.
Canonical writers MUST emit all three matter directives.
Missing matter directives MAY be synthesized only in compatibility mode.
Nested canonical examples use longer outer fences such as :::: and ::::: to satisfy the fence-length nesting rule.

4. Universal Structural Directives¶

:::section
:::subsection
:::subsubsection

4.1 Placement rule¶

Universal structural directives MAY appear only inside a matter directive.

4.2 Lowering rule¶

They lower directly to the matching universal AST node.

5. Carrier Directive Doctrine¶

Carrier directives serialize carrier-native nodes.
Carrier-native structural directives lower to carrier-native nodes while still preserving the universal section spine.
Carrier directives MUST appear only where the declared carrierArchetype allows them.

6. Carrier Directive Registry¶

Carrier	Canonical directives
`stageFrame`	`:::frameset`, `:::frame`, `:::frame-section`, `:::appendix-frameset`, `:::zone`
`codexSpread`	`:::codex`, `:::chapter`, `:::spread`, `:::appendix`, `:::reference-apparatus`
`scrollStream`	`:::stream`, `:::file-segment`, `:::anchor`, `:::support-matter`, `:::jump`
`tableauPageCollage`	`:::tableau-document`, `:::page-family`, `:::tableau-page`, `:::region-group`, `:::hero-region`, `:::support-region`
`sheetField`	`:::field-document`, `:::sheet`, `:::perimeter`, `:::top-band`, `:::bottom-band`, `:::side-band`, `:::region`
`ledgerRegister`	`:::register`, `:::collection`, `:::schema`, `:::record`, `:::form`, `:::dashboard`, `:::constraint`
`box`	`:::box`, `:::tag-catalog`, `:::fragment`, `:::subcollection`, `:::cluster`, `:::saved-view`
`conversationThread`	`:::thread`, `:::participant-profile`, `:::topic-briefing`, `:::conduct-doctrine`, `:::episode`, `:::branch`, `:::turn`, `:::attachment-ref`, `:::outcome`

7. Structural Precedence¶

Universal structure directives always create the universal section nodes.
Carrier-native structural directives may realize the same structural boundary at the carrier layer.
When a carrier-native structural directive already creates the intended structural boundary, parsers MUST NOT synthesize a duplicate sibling universal section.

8. Canonical Example¶

The following example is canonical full-valid source.

---
kind: artifact
carrier: codex/spread
genre: ext/reference-codex
title: Example Codex
composition-grammar: codex/default
---

::::front-matter
:::::codex {title="Prelims"}
Edition: working draft.
:::::
::::

::::main-matter
:::::chapter {title="Findings"}
Core chapter body.
:::::
::::

::::back-matter
:::::reference-apparatus
Glossary and sources.
:::::
::::