---
title: "roundtrip-lib — Mova code model"
description: "Mova code model of tools/roundtrip/src/lib.rs: components with their labels, obernants and the model text."
url: "https://groupants.elamur.ai/free/en/mova/tools/roundtrip/src/lib.rs.groupant/"
---
Elamur: [Mova](https://md.mova.elamur.ai/free/en/) · [Dictionary](https://md.dictionary.elamur.ai/free/en/) · [Research](https://md.research.elamur.ai/free/en/) · **Groupants**

This page as HTML: <https://groupants.elamur.ai/free/en/mova/tools/roundtrip/src/lib.rs.groupant/>

# roundtrip-lib

The groupant beside tools/roundtrip/src/lib.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

- **kind:** groupant
- **status:** partial source bound model
- **source:** [`tools/roundtrip/src/lib.rs`](https://github.com/ElamurAI/mova-free/blob/main/tools/roundtrip/src/lib.rs)
- **source SHA-256:** `366f25c83a674bd1…`
- **repository folder:** [`tools/roundtrip/src/lib.rs.groupant`](https://github.com/ElamurAI/mova-free/tree/main/tools/roundtrip/src/lib.rs.groupant)
- **repository commit:** `855da7bd4a7b`

> **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 | [approximant](#approximant) |
| **ast** | partial | `syntax.json` |
| **cost** | partial | [invariant-and-cost](#invariant-and-cost) |
| **descriptant** | present | [descriptant](#descriptant) |
| **invariant** | partial | [invariant-and-cost](#invariant-and-cost) |
| **tests** | bounded checks | [tests](#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 source derived model | [behavior_complement](#behavior-complement) |
| `reverse_reconstruction` | reverse_reconstruction | partial source derived model | [reverse_reconstruction](#reverse-reconstruction) |
| `environment_fallback` | environment_fallback | partial source derived model | [environment_fallback](#environment-fallback) |
| `path_join` | path_join | partial source derived model | [path_join](#path-join) |
| `export_join` | export_join | partial source derived model | [export_join](#export-join) |
| `model_load_gap` | model_load_gap | partial source derived model | [model_load_gap](#model-load-gap) |

## Model text


### descriptant

#### roundtrip-lib

2026-10-31 prospective epoch retained externally before edits.

Publishes layer modules and conditionally test module. model_path reads MOVA_DATA; absent or non-Unicode value falls back to HOME plus /mova-data, then appends en/models/en.bin.

No annotator/model loading, live corpus, full suite, teacher, GPU or persistent-learning evidence. No executable percentage surrogate: categorical codecs/effects need a useful metric before future caps 1/2/5/10%.

Exact recovery with residual is a diagnostic codec observation. It is not evidence of normal generative equivalence, semantic understanding or persistent learning. Production source is preserved; only isolated tests are appended where needed.

### approximant

#### Forward relation

Publishes layer modules and conditionally test module. model_path reads MOVA_DATA; absent or non-Unicode value falls back to HOME plus /mova-data, then appends en/models/en.bin.

Domain: bounded synthetic values, valid source-specific coordinates, nonoverflowing counts, available allocation; fixed environment controls. Relations are source-derived partial models with finite checks, not universal proofs.

##### Composition

Source children delimit real function scopes, sharing syntax. Real pipeline joins R4 frame reconstruction to Realizer then R3 tree script and R2 token decode; report consumes aggregated tally. Independent path/CLI branches are not fictitious codec callers.

### catalog

### behavior_complement

Subject: roundtrip-lib, source hash 366f25c83a674bd1917578e2c985b4c0585f02a1d3fa53e4101c7e9d0a895606; transition observation.

model_path performs no existence check, file open, model load or directory creation. Exports do not themselves run a roundtrip.

Domain: bounded synthetic values, valid source-specific coordinates, nonoverflowing counts, available allocation; fixed environment controls. Relations are source-derived partial models with finite checks, not universal proofs.

Evidence: external wave32 rt_core receipt includes native-commands.json, exact named outcomes twice debug/twice release, raw status/log files, compiled production controls with byte restoration and paired syntax. Only named synthetic helpers execute; model_path/export and live CLI paths have representation/source evidence.

Status: partial source-derived model.

### reverse_reconstruction

Subject: roundtrip-lib, source hash 366f25c83a674bd1917578e2c985b4c0585f02a1d3fa53e4101c7e9d0a895606; transition observation.

A resulting PathBuf admits different environment assignments: explicit MOVA_DATA and fallback HOME can yield same path. No unique environment or model contents can be recovered from the path.

Domain: bounded synthetic values, valid source-specific coordinates, nonoverflowing counts, available allocation; fixed environment controls. Relations are source-derived partial models with finite checks, not universal proofs.

Evidence: external wave32 rt_core receipt includes native-commands.json, exact named outcomes twice debug/twice release, raw status/log files, compiled production controls with byte restoration and paired syntax. Only named synthetic helpers execute; model_path/export and live CLI paths have representation/source evidence.

Status: partial source-derived model.

### environment_fallback

Subject: roundtrip-lib, source hash 366f25c83a674bd1917578e2c985b4c0585f02a1d3fa53e4101c7e9d0a895606; transition observation.

MOVA_DATA successful Unicode lookup dominates HOME; an empty successful MOVA_DATA remains an empty base rather than invoking fallback.

Domain: bounded synthetic values, valid source-specific coordinates, nonoverflowing counts, available allocation; fixed environment controls. Relations are source-derived partial models with finite checks, not universal proofs.

Evidence: external wave32 rt_core receipt includes native-commands.json, exact named outcomes twice debug/twice release, raw status/log files, compiled production controls with byte restoration and paired syntax. Only named synthetic helpers execute; model_path/export and live CLI paths have representation/source evidence.

Status: partial source-derived model.

### path_join

Subject: roundtrip-lib, source hash 366f25c83a674bd1917578e2c985b4c0585f02a1d3fa53e4101c7e9d0a895606; transition observation.

Suffix en/models/en.bin is joined lexically; symlinks and canonicalization do not run and relative bases stay relative.

Domain: bounded synthetic values, valid source-specific coordinates, nonoverflowing counts, available allocation; fixed environment controls. Relations are source-derived partial models with finite checks, not universal proofs.

Evidence: external wave32 rt_core receipt includes native-commands.json, exact named outcomes twice debug/twice release, raw status/log files, compiled production controls with byte restoration and paired syntax. Only named synthetic helpers execute; model_path/export and live CLI paths have representation/source evidence.

Status: partial source-derived model.

### export_join

Subject: roundtrip-lib, source hash 366f25c83a674bd1917578e2c985b4c0585f02a1d3fa53e4101c7e9d0a895606; transition observation.

pipeline joins tree, frames, world and report consumes tally; declarations make interfaces available but do not establish caller correctness.

Domain: bounded synthetic values, valid source-specific coordinates, nonoverflowing counts, available allocation; fixed environment controls. Relations are source-derived partial models with finite checks, not universal proofs.

Evidence: external wave32 rt_core receipt includes native-commands.json, exact named outcomes twice debug/twice release, raw status/log files, compiled production controls with byte restoration and paired syntax. Only named synthetic helpers execute; model_path/export and live CLI paths have representation/source evidence.

Status: partial source-derived model.

### model_load_gap

Subject: roundtrip-lib, source hash 366f25c83a674bd1917578e2c985b4c0585f02a1d3fa53e4101c7e9d0a895606; transition observation.

A constructed path says nothing about model existence, serialization validity or annotation accuracy; live loading is excluded from this evidence epoch.

Domain: bounded synthetic values, valid source-specific coordinates, nonoverflowing counts, available allocation; fixed environment controls. Relations are source-derived partial models with finite checks, not universal proofs.

Evidence: external wave32 rt_core receipt includes native-commands.json, exact named outcomes twice debug/twice release, raw status/log files, compiled production controls with byte restoration and paired syntax. Only named synthetic helpers execute; model_path/export and live CLI paths have representation/source evidence.

Status: partial source-derived model.

### tests

#### Native evidence


17 exact named checks total (16 library, one CLI helper), each twice debug and twice release, numeric exits zero and sorted outcomes identical. Native metadata and raw receipts are in the external wave32 rt_core run directory. No optional model tests execute. lib.rs has compile/representation evidence only.

Four compiled production controls alter class precedence, Block grouping, world boundary XOR and frame lemma patching. Each fails its named runtime assertion (exit101), restores exact source SHA256 and passes restored check (exit0). No assertion-only mutants, survivors or bug repairs. These controls do not establish complete coverage.

Two fresh syntax projections agree for each of nine sources. Production bytes are preserved as exact base prefixes. Format only appended test modules before final native receipts. CLI spec helper errors precede any reader; actual model-loading pipeline is excluded.

### invariant-and-cost

#### Invariant and cost

model_path performs no existence check, file open, model load or directory creation. Exports do not themselves run a roundtrip.

A resulting PathBuf admits different environment assignments: explicit MOVA_DATA and fallback HOME can yield same path. No unique environment or model contents can be recovered from the path.

Path assembly O(environment string bytes), allocation proportional to returned path. Module declarations have compile/representation evidence only; no runtime codec cost is implied.

Domain: bounded synthetic values, valid source-specific coordinates, nonoverflowing counts, available allocation; fixed environment controls. Relations are source-derived partial models with finite checks, not universal proofs.