---
title: "rt-mixed-heb-tokens — Mova code model"
description: "Mova code model of tools/roundtrip/src/mixed/heb.rs: components with their labels, obernants and the model text."
url: "https://groupants.elamur.ai/free/en/mova/tools/roundtrip/src/mixed/heb.rs.groupant/tokens.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/mixed/heb.rs.groupant/tokens.groupant/>

# rt-mixed-heb-tokens

The groupant beside tools/roundtrip/src/mixed/heb.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_fragment
- **status:** partial source bound model
- **source:** [`tools/roundtrip/src/mixed/heb.rs`](https://github.com/ElamurAI/mova-free/blob/main/tools/roundtrip/src/mixed/heb.rs)
- **source SHA-256:** `875be40516fae16e…`
- **covers:** tokens_down(tokens_up(p))=p under tokenizer coverage; wrap bytes and raw whitespace chunks restore original representation. (bytes 3744–6771)
- **part of:** [rt-mixed-heb](https://md.groupants.elamur.ai/free/en/mova/tools/roundtrip/src/mixed/heb.rs.groupant/)
- **repository folder:** [`tools/roundtrip/src/mixed/heb.rs.groupant/tokens.groupant`](https://github.com/ElamurAI/mova-free/tree/main/tools/roundtrip/src/mixed/heb.rs.groupant/tokens.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** | symbolic source derived | [invariant](#invariant) |
| **descriptant** | present | [descriptant](#descriptant) |
| **invariant** | partial | [invariant](#invariant) |
| **tests** | executed 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) |
| `raw_chunk` | raw_chunk | partial source derived model | [raw_chunk](#raw-chunk) |
| `gap_index` | gap_index | partial source derived model | [gap_index](#gap-index) |
| `wrap_boundary` | wrap_boundary | partial source derived model | [wrap_boundary](#wrap-boundary) |
| `tail_restore` | tail_restore | partial source derived model | [tail_restore](#tail-restore) |

## Model text


### descriptant

#### Descriptant

##### Prospective epoch

2026-10-31 source review predicted: tokens_down(tokens_up(p))=p under tokenizer coverage; wrap bytes and raw whitespace chunks restore original representation. Resource model: Tokenization/NFC O(B) plus ordered raw/gap map lookup; O(B+tokens) retained text. External prospective.md predates test additions and preserves APIs, effect order, hazards and interaction hypotheses.

##### Observed epoch

Bounded real helper checks in tests.md constrain these models; syntax is a partial lexical projection with no macro expansion, name resolution or proof. Production expressions unchanged; six inline test modules added. Compiled mutants are temporary and exactly restored. Existing malformed-input and nonfinite domains remain explicit, not silently repaired. Parent composes this scope with siblings without adding overlapping costs twice.

Narrow NFC token residual codec scope; finite checks do not cover all inputs. Parent effects and other functions are outside this fragment.

### approximant

#### Forward relation

tokens_down(tokens_up(p))=p under tokenizer coverage; wrap bytes and raw whitespace chunks restore original representation.

Domain: Scope: NFC token residual codec. Valid UTF-8; words/forms lengths agree; positive group sizes sum to words; heads are zero or in range; generated scripts use unique valid Take indices. Residual metrics are finite nonnegative estimates, not compressed byte lengths.

### invariant

#### Invariant and cost

##### Invariant

Scope: NFC token residual codec. Valid UTF-8; words/forms lengths agree; positive group sizes sum to words; heads are zero or in range; generated scripts use unique valid Take indices. Residual metrics are finite nonnegative estimates, not compressed byte lengths.

##### Cost

Tokenization/NFC O(B) plus ordered raw/gap map lookup; O(B+tokens) retained text.

##### Limits

Narrow NFC token residual codec scope; finite checks do not cover all inputs. Parent effects and other functions are outside this fragment. No percentage surrogate is implemented: categorical parsing/effect observations lack an admitted numerical error metric. Any future profile must define its metric/domain and use only1/2/5/10 percent caps.

### models

## Typed source-bound relations

Subject: exact source SHA-256 in manifest. Domain and resource premises are in invariant.md. Each model is partial, source-derived, over a single helper invocation or the described finite trace. Complements are proposed inner exclusions under those premises; reverse relations retain all compatible antecedents, with no unique inverse claim. The oracle is the named checks in tests.md; unexecuted cases remain hypotheses. No numerical approximation certificate.

### behavior_complement

Within this scoped helper relation, outputs violating the stated forward equation or its preserved fields are excluded under the domain premises; this is a partial source-derived inner exclusion, not a claim about untested panics. raw map keys are whitespace-run ordinals, not token positions.

### reverse_reconstruction

Original gaps/NFC chunks are absent from canonical tokens; these erased variants form the inverse fiber.

### raw_chunk

raw map keys are whitespace-run ordinals, not token positions

### gap_index

gaps indexed by (sentence,token) and default canonical_gap

### wrap_boundary

all-wrapper text core returns lead=len and trail=0

### tail_restore

tail appended before unnfc and exterior wrap

### tests

#### Checks and evidence

Named source/helper checks: mixed::heb::tests::tokens_come_back, mixed::heb::tests::script_gives_the_tree_back.

Wave32 on2026-10-31:10 distinct exact tests passed twice debug and twice release, with equal sorted named outcomes. This node claims only its listed subset; empty subset means source review only. Five actual source-behavior mutants compiled, failed assertions, restored exact bytes/hash, and passed focused green reruns. No assertion-only mutants; existing swapped-input controls are separate. Receipt bundle: $MOVA_DATA/runs/octopus-wave32-rt_mixed-2026-10-31 (native-commands.json, source-test-map.json, mutation-results.json, *.status/*.log). No live corpus, teacher, frozen assessment, download or production data used.

Narrow NFC token residual codec scope; finite checks do not cover all inputs. Parent effects and other functions are outside this fragment.