Elamur Groupantsworld-lessons-parse
The groupant beside world/src/lessons.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-lessons-parse-behavior-complement | behavior_complement | partial source model | behavior-complement |
world-lessons-parse-reverse-reconstruction | reverse_reconstruction | partial source model | reverse-reconstruction |
world-lessons-parse-coupling | constraint_relation | partial source model | coupling |
Model text
forward
Parse supplied line-oriented text by first colon; repeated scalar fields replace, list fields append. Required nonzero lesson number, nonempty answer, at least one exercise and test. Range syntax and expressions are deferred until draw. No implicit train/test partition is inferred from text.
behavior-complement
U is finite supplied texts paired with Result observations. Inner absent transitions include successful unknown fields or missing required fields. Whitespace normalization and default fields are part of the relation; no claim of complete grammar validation.
reverse-reconstruction
B(l) contains all texts whose recognized fields build l, including arbitrary blank/comment lines and overwritten scalar prefixes. File string is an input retained in l. Lost comments make this noninjective.
coupling
Partition membership is the field label; identical exercise and exam strings are accepted. Separation of containers does not establish unseen semantic content.
invariant
Successful observations obey the declared forward relation with the same supplied state and order. Failure is explicit; no hidden label or retained-state guarantee is introduced.
cost
One pass over bytes plus owned field copies: O(B) time/storage, ignoring allocator failures.
composition
Evaluation and substitution share numeric bindings; field labels choose template containers. Child relations must agree on intermediate state, not merely final counts. Partial syntax binds the source; macro contents are opaque.
epoch-memory
Initial review predicted arithmetic overflow and finite-pool boundary failures. Old native code failed six named witnesses: overflow, empty templates, name exhaustion, full-width range, reversed range and seed overflow. Narrow repairs retain public signatures; finite observations do not establish arbitrary-input totality. See file evidence.md for hashes and repeated results.
checks
Eight wave12_models tests plus two existing lesson tests. Independent 19 by 19 by 7 arithmetic cases, precedence/eager failure literals, partition/substitution fixtures and exactly 2000 rejected RNG draws. Runtime guard mutations must fail named assertions. Evidence is finite; no whole-world or live course claim.
This page in Markdown → https://md.groupants.elamur.ai/free/en/mova/world/src/lessons.rs.groupant/parse.groupant/