Elamur Groupantsworld-primers-reachability
The groupant beside world/src/primers.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 |
| composition | partial source model | composition |
| 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 |
|---|---|---|---|
world-primers-reachability-behavior-complement | behavior_complement | partial source model | behavior-complement |
world-primers-reachability-reverse-reconstruction | reverse_reconstruction | partial source model | reverse-reconstruction |
world-primers-reachability-coupling | constraint_relation | partial source model | coupling |
world-primers-reachability-observation-fiber | information_loss | partial source model | observation-fiber |
Model text
forward
Normalize number words, collect unsigned digit/comma runs, deduplicate and combine with constants 12,60,100,7,24. Enumerate sum/product/absolute difference/exact quotient for one or two operations; checked sum/product omit results outside i64.
invariant
All generated candidates are nonnegative representable i64 values. Equal source numbers are deduplicated and same-value base pairs are skipped unless the second is an appended constant. Signs/decimals are not faithfully parsed as numbers.
cost
With U distinct numeric runs, one-step vector O(U(U+5)); second step O(U(U+5)^2) operations; O(U^2) vector storage. Temporary operator vectors remain allocated.
composition
The real crate::numbers::normalize is called on supplied number words. The finite oracle uses i128 expression enumeration for 36 numeric pairs and 41 answers each; a large-value witness excludes wrapped negative output.
epoch-memory
2026-10-30 wave11. Synthetic old-code witnesses failed before narrow repairs: frame display lost attrs/cond; marker spelling priority selected an earlier answer; unchecked arithmetic panicked; dotted page answer 57 was mistaken for an item. Current tests preserve these counterexamples. No optimization, percentage-error surrogate or general correctness claim.
checks
cargo test -p world --lib primers::wave11_models -- --test-threads=1. See file-root evidence.md for repeated debug/release identities and compiled mutants. Syntax is a source-bound partial projection; macro bodies are opaque.
behavior-complement
Subject/revision: manifest source hash and this scope. Universe: bounded supplied inputs and terminating observations under fixed dependencies and successful allocation. Inner absent-behavior model excludes any transition violating: All generated candidates are nonnegative representable i64 values. Equal source numbers are deduplicated and same-value base pairs are skipped unless the second is an appended constant. Signs/decimals are not faithfully parsed as numbers. External effects and unmodeled malformed states are unknown, not excluded. Finite tests support only named fixtures.
reverse-reconstruction
Subject/revision: manifest source hash. Domain: the scoped forward input/output relation, fixed dependencies and successful allocation. Operator is the full compatible preimage: For answer a retain every normalized source-number set admitting a permitted expression tree of depth at most two, plus singleton equality. Many texts normalize to each set; multiplicities are lost and operands may be reused. This is a partial source model, not an implemented complete inverse search; no unique causal explanation is inferred.
coupling
Subject/revision: manifest source hash. Constraint relation on shared identities/intermediate states: The real crate::numbers::normalize is called on supplied number words. The finite oracle uses i128 expression enumeration for 36 numeric pairs and 41 answers each; a large-value witness excludes wrapped negative output. Source inspection and actual finite joins are distinguished.
observation-fiber
Subject/revision: manifest source hash. Information-loss relation holds inputs in the same fiber when their declared observation agrees: This heuristic can accept using implicit constants and repeated operands, or reject valid problems needing more operations. Passing is an OCR plausibility signal, not proof of the story's answer. Finite correspondence only; unrestricted soundness/completeness is not established.
This page in Markdown → https://md.groupants.elamur.ai/free/en/mova/world/src/primers.rs.groupant/reachability.groupant/