Elamur Groupantsanswer-span-predicate
The groupant beside world/src/span.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 source model | forward |
| ast | partial | ../syntax.json |
| cost | partial source model | cost |
| descriptant | partial source model | epoch-memory |
| invariant | partial source model | invariant |
| tests | partial source model | checks |
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 |
|---|---|---|---|
answer-span-predicate-behavior-complement | behavior_complement | partial source model | behavior-complement |
answer-span-predicate-reverse-reconstruction | reverse_reconstruction | partial source model | reverse-reconstruction |
answer-span-predicate-lexical-rank | priority_relation | partial source model | lexical-rank |
answer-span-predicate-suffix-equivalence | information_loss | partial source model | suffix-equivalence |
answer-span-predicate-finite-rank-fibers | reverse_reconstruction | bounded native correspondence | finite-rank-fibers |
Model text
model
answer-span-predicate
Subject: world/src/span.rs, whole-file SHA-256 in manifest, baseline 4279da541. Domain: finite acyclic valid trees with consistent child lists, valid indices and terminating dependencies. Observation: a single call return, not semantic truth or reachability. Hold Tree, ans::lemmas and types::FEELING dependencies fixed; parser/model loading and external caller wiring are gaps. All entries are source-derived partial models. Exact-target definitions are not executable inverses; finite tests cannot establish universal correspondence.
forward
Scan caller predicates then token ranks; return first admissible minimum.
invariant
Tie keeps earliest token; PROPN has rank 3.
cost
O(pnL) with opaque morphology allocations.
epoch-memory
2026-10-29: initial source-bound epoch. Preserve Num bypass, global Feel selection, early-return cleanup suppression, and verb_kids comment mismatch: code expands Xcomp only and checks no shared subject. No source changes or task-accuracy claim. Partial syntax has no semantic analysis or macro expansion.
checks
Structural inventory checks hashes, references, types and node bounds only. Proposed oracle: enumerate small annotated acyclic trees and compare literal expected returns, including None and labels; mutate priority or echo inequality to obtain a red control. Any executed bounded evidence is recorded separately in root evidence.md; catalog examples remain proposed until recorded there.
composition
Leaf scope shares immutable tree/question/helper contracts. Overlap with parent is not extra runtime work. Dependencies outside range remain opaque.
behavior-complement
U=(Tree,preds) x Option<index>; R=find_pred. Inner U minus R excludes out-of-range outputs, rank-3 outputs and later equal-rank hits when earlier hits exist for first admissible predicate.
Assumptions/evidence/status: common domain above; source-derived partial relation at bound revision. Approximation and held-fixed inputs are stated in the relation. Oracle: finite literal fixtures exercising both membership and nonmembership against the actual function, preserving ambiguous preimages. No linguistic correctness or universal proof inferred.
reverse-reconstruction
For Some(i), retain all lists with a first admissible predicate whose minimum (rank,index) hit is i; preceding entries may match only rank 3. None includes empty lists, no hits and rank-3-only hits. Morphology ambiguity remains.
Assumptions/evidence/status: common domain above; source-derived partial relation at bound revision. Approximation and held-fixed inputs are stated in the relation. Oracle: finite literal fixtures exercising both membership and nonmembership against the actual function, preserving ambiguous preimages. No linguistic correctness or universal proof inferred.
lexical-rank
Fixed predicate and hit set: choose minimum (rank,index), requiring rank<3. Hit means equal lemma, equal form or ans::lemmas(form) membership. Changing POS can change winner without changing spelling.
Assumptions/evidence/status: common domain above; source-derived partial relation at bound revision. Approximation and held-fixed inputs are stated in the relation. Oracle: finite literal fixtures exercising both membership and nonmembership against the actual function, preserving ambiguous preimages. No linguistic correctness or universal proof inferred.
suffix-equivalence
Any preds suffix after first accepted predicate is unobserved. Inserting predicates having no admissible matches before it preserves output. This is a sufficient equivalence family, not exhaustive.
Assumptions/evidence/status: common domain above; source-derived partial relation at bound revision. Approximation and held-fixed inputs are stated in the relation. Oracle: finite literal fixtures exercising both membership and nonmembership against the actual function, preserving ambiguous preimages. No linguistic correctness or universal proof inferred.
wave6
Native selection observations, 2026-10-30
Revision: exact source SHA in this manifest. Observations are single terminating calls. Tree fixtures are directly annotated, acyclic and index-valid; dependencies are compiled from this checkout. No parser or teacher is loaded. Metric is exact equality of optional indices/text and rule labels; zero tolerance. Exhaustive claims apply only to explicitly bounded domains, with no semantic accuracy or general Rust proof.
finite-rank-fibers
Fix three forms/lemmas to ruby, preds=[ruby], rank tags {VERB,ADJ,NOUN,PROPN}. Domain is all 4^3=64 rank triples. A(r)=argmin (r_i,i) among r_i<3, or None if empty. B(j) contains every triple with r_j<3, each earlier rank strictly larger and each later rank at least r_j; B(None)={(3,3,3)}. The native test enumerates entire actual and oracle maps of fibers and compares equality, including earliest ties. This is complete for this finite tag set; AUX and morphology are outside the enumeration. Two additional literal caller-order observations show an earlier predicate noun outranks a later predicate verb. Test predicate_rank_complete_fibers_and_caller_order.
This page in Markdown → https://md.groupants.elamur.ai/free/en/mova/world/src/span.rs.groupant/predicate.groupant/