Elamur Groupantsmova-nightingale-model
The groupant beside tools/nightingale/src/model.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 approximant |
| Ast | partial | syntax.json |
| Composition | partial | Composition |
| Cost | partial | Cost |
| Descriptant | present | Descriptant |
| Invariant | partial | Invariant |
| Tests | finite evidence | 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.
| relation | type | label | where |
|---|---|---|---|
| Behavior complement | behavior complement | partial source derived model | Behavior complement |
| Reverse reconstruction | reverse reconstruction | partial source derived model | Reverse reconstruction |
Model text
Descriptant
A loaded model: per-label counts, the interpolated absolute-discounting bigram language model with a character spelling back-off, held-out bits per token, trends and the varieties' composed counts. Source: tools/nightingale/src/model.rs.
Forward approximant
load: meta and body hash checked; pooled unigrams, left-context discount mass, spelling model over kept types; p1, p2, bits, bits_per_token; variety(kind, payload, label) = c_std * 2^shift.
Invariant
P2 sums to one over the vocabulary for a seen context; the body must hash to its meta; deltas must belong to the lineage.
Cost
Load O(records) memory (2.2 GB peak for the 6.4 M-record English probe); a token O(1) hash lookups.
Composition
Parent: nightingale.
Behavior complement
Never writes; an unknown label counts 0. Evidence status: source-derived model with finite checks, not a proof.
Reverse reconstruction
The model is a function of its parts (lineage); counts are exact, probabilities derived.
Tests
Checks
tests/model.rs: more text fewer bits; the shuffled control; measure on the probes. These are finite fixtures and measurements; not a proof.
History
2026-11-06 · document
Epoch 2026-11-06
First model, written with the source (the Nightingale: one per language under the Eel; a standard naturalness model with variety deltas).
Provenance
This page in Markdown → https://md.groupants.elamur.ai/free/en/mova/tools/nightingale/src/model.rs.groupant/