Elamur Groupantsmodelcheck-library-section-fences
The groupant beside tools/modelcheck/src/sections.rs in the Mova repository: what the code computes, what it never does, how to go back from its outputs, its invariants, cost and checks.
Facts
Implementation material. A Mova code model describes this code at one source revision: partial models, finite checks and their stated scope. It is not a reviewed general exposition, and its labels are shown as written, never raised.
Components
| component | label | where |
|---|---|---|
| approximant | partial | Forward |
| ast | partial | ../syntax.json |
| cost | partial | Cost |
| descriptant | partial | Descriptant |
| invariant | partial | Invariant |
| tests | partial | Tests |
Obernants
The typed relations around the forward model: the behaviour complement (what the code never does), the reverse reconstruction (every input compatible with an output) and specialised views.
| id | type | label | where |
|---|---|---|---|
behavior_complement | behavior_complement | partial relational specification | behavior_complement |
reverse_reconstruction | reverse_reconstruction | partial relational specification | reverse_reconstruction |
closing_threshold | closing_threshold | partial relational specification | closing_threshold |
opening_info_constraint | opening_info_constraint | partial relational specification | opening_info_constraint |
duplicate_count_semantics | duplicate_count_semantics | partial relational specification | duplicate_count_semantics |
unterminated_fence_suffix | unterminated_fence_suffix | partial relational specification | unterminated_fence_suffix |
Model text
Subject: current manifest source SHA and exact UTF-8 range [254,3689) of sections.rs. The observation is one completed scoped call with adequate resources; source-derived relations are partial specifications. Filesystem checks describe sequential reads, not an atomic snapshot.
Forward
Scan lines with state Outside or (opening marker,run length). Outside, admit <=3-space backtick/tilde runs >=3 with backtick-info restriction; otherwise count exact column-zero H2 string. Inside, close only same marker at least opening length with whitespace-only suffix and skip every line from counting.
Invariant
Only exact unfenced H2 lines count. Closing fence lines never count. The scan counts all occurrences so duplicate headings remain detectable; it is not a Markdown renderer.
Cost
O(B) scanned bytes and O(H) heading-string allocation for B artifact bytes and H section bytes; constant fence state. Each component's section read rescans independently.
Descriptant
Wave34, 2026-10-31: deeper scope retained under its existing parent without replacing historical views. Decode reuse was proposed before edits and checked against actual reference decoding; behavioral controls and repeated native receipts remain finite evidence. No numerical surrogate is justified for categorical validation outcomes; no percentage accuracy or complete semantic proof is claimed.
Tests
Exact native test: groupant_tests::groupant_validation_negative_controls_and_open_extensions. Parent tests additionally exercise integration and failure order. Current evidence is in ../../wave34-evidence.md; old evidence remains explicitly historical in wave33-evidence.md at the source root.
behavior_complement
Exclude positive heading increments for lines inside a recognized fence, padded headings, wrong heading level or heading text with trailing markup. These excluded transitions are defined by current fence state and exact line equality.
Assurance: source-derived partial relation; fixed source revision and stated scope. Oracle: groupant_tests::groupant_validation_negative_controls_and_open_extensions. Finite observations do not establish universal completeness.
reverse_reconstruction
Observed count k admits all texts whose outside-state exact-heading events number k. Fence contents and unrelated lines remain unconstrained; k=1 cannot recover a unique document.
Assurance: source-derived partial relation; fixed source revision and stated scope. Oracle: groupant_tests::groupant_validation_negative_controls_and_open_extensions. Finite observations do not establish universal completeness.
closing_threshold
Given state (m,L), a line closes iff indent<=3, marker=m, run>=L and remaining suffix is space/tab only. Short runs or other marker preserve the state.
Assurance: source-derived partial relation; fixed source revision and stated scope. Oracle: groupant_tests::groupant_validation_negative_controls_and_open_extensions. Finite observations do not establish universal completeness.
opening_info_constraint
Outside-state backticks with another backtick in suffix do not open; tilde suffixes have no equivalent restriction. The distinction is intentional narrow grammar.
Assurance: source-derived partial relation; fixed source revision and stated scope. Oracle: groupant_tests::groupant_validation_negative_controls_and_open_extensions. Finite observations do not establish universal completeness.
duplicate_count_semantics
A document with two admitted exact headings yields 2; the caller requires count=1 and rejects both missing and ambiguous sections. Early success at first match would weaken validation.
Assurance: source-derived partial relation; fixed source revision and stated scope. Oracle: groupant_tests::groupant_validation_negative_controls_and_open_extensions. Finite observations do not establish universal completeness.
unterminated_fence_suffix
After an opening without an admissible closer, all later headings are suppressed. Prefixing an opener can therefore change the compatible-document fiber for an unchanged suffix.
Assurance: source-derived partial relation; fixed source revision and stated scope. Oracle: groupant_tests::groupant_validation_negative_controls_and_open_extensions. Finite observations do not establish universal completeness.
Epoch 2026-11-04
Moved from lib.rs (component validation) to sections.rs, shared with consolidation. The automaton is now lines (per-line fenced flag, delimiter lines included), unclosed_fence and heading_count; the counted relation is unchanged: exact column-zero ## Name lines outside fences. New in this range: h2_names lists every unfenced line starting with ## . Additional oracle: sections::tests::sections_follow_the_plain_h2_grammar (duplicates and unclosed fences as negative controls).
This page in Markdown → https://md.groupants.elamur.ai/free/en/mova/tools/modelcheck/src/sections.rs.groupant/section-fences.groupant/