---
title: "treeagree-main-json-escape — Mova code model"
description: "Mova code model of tools/treeagree/src/main.rs: components with their labels, obernants and the model text."
url: "https://groupants.elamur.ai/free/en/mova/tools/treeagree/src/main.rs.groupant/json-escape.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**

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# treeagree-main-json-escape

The groupant beside tools/treeagree/src/main.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/treeagree/src/main.rs`](https://github.com/ElamurAI/mova-free/blob/main/tools/treeagree/src/main.rs)
- **source SHA-256:** `fadc15525d579f86…`
- **covers:** json-escape (bytes 3555–3977)
- **part of:** [treeagree-main](https://md.groupants.elamur.ai/free/en/mova/tools/treeagree/src/main.rs.groupant/)
- **repository folder:** [`tools/treeagree/src/main.rs.groupant/json-escape.groupant`](https://github.com/ElamurAI/mova-free/tree/main/tools/treeagree/src/main.rs.groupant/json-escape.groupant)
- **repository commit:** `48f2e6f74146`

> **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 | `model.md` |
| **ast** | partial | `../syntax.json` |
| **composition** | partial | [Composition](#composition) |
| **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) |
| `control_partition` | control_partition | partial source derived model | [control_partition](#control-partition) |
| `utf8_identity` | utf8_identity | partial source derived model | [utf8_identity](#utf8-identity) |
| `size_bound` | size_bound | partial source derived model | [size_bound](#size-bound) |
| `transport_gap` | transport_gap | partial source derived model | [transport_gap](#transport-gap) |

## Model text


### descriptant

#### Descriptant

output starts/ends quote; quotes, backslashes, newline and tab escape, other controls below U+0020 use four hex digits, remaining Unicode scalars copy.

##### Epoch 2026-10-31

Prospective source reading identified conditional input alignment, information loss and failure order before tests. Existing production code is retained; added tests use actual helpers. Finite results update this source-bound model, not all parser/corpus semantics.

No executable percentage surrogate has a justified observation metric for these categorical/effectful APIs. Future profiles require metric, domain and real-reference evidence at caps 1/2/5/10%; no higher cap. Syntax is partial lexical Rust projection without macro expansion or semantic resolution.

### approximant

## Forward approximant

output starts/ends quote; quotes, backslashes, newline and tab escape, other controls below U+0020 use four hex digits, remaining Unicode scalars copy.

### Composition

This fragment is the exact byte-scoped helper identified in the manifest; its relation is restricted to the operations above.

The containing source wires this scoped relation to its callers. Treeagree proposal→gate→commit and treebanks parse→match→collect→render are actual joins; parsecmp is an independent diagnostic path. The external group model distinguishes these tags.

### catalog

## Typed models for treeagree-main-json-escape

Subject: source SHA-256 `fadc15525d579f8681612a25d06356fed2156f8f7054b54e61ffc07c5a590032`; manifest supplies exact source/byte scope. Domain: admitted states in forward model, nonoverflow arithmetic and successful allocations. Observation: one terminating invocation, except explicitly described file trace. Source-derived partial relations; named finite tests constrain selected cases only. Each entry holds arguments and environment fixed except its stated intervention.

### behavior_complement

On completion no raw control scalar below U+0020 occurs between quotes; no file effects.

Operator: inner exclusion on admitted domain. Evidence: source branch derivation plus tests.md; unexercised branches remain hypotheses. Oracle: evaluate the scoped actual helper on admissible fixtures and compare this observation. No universal proof.

### reverse_reconstruction

JSON decoding of this valid escaped string uniquely recovers source scalars; json_field is not that decoder for unicode controls.

Operator: compatible antecedent relation, retaining ambiguity. Evidence: source branch derivation plus tests.md; unexercised branches remain hypotheses. Oracle: evaluate the scoped actual helper on admissible fixtures and compare this observation. No universal proof.

### control_partition

Newline/tab take short escapes before general control case, including carriage return in hex case.

Operator: specialized observation relation under the stated fixed inputs. Evidence: source branch derivation plus tests.md; unexercised branches remain hypotheses. Oracle: evaluate the scoped actual helper on admissible fixtures and compare this observation. No universal proof.

### utf8_identity

Noncontrol nonquote Unicode copies exactly, without normalization or ASCII transliteration.

Operator: specialized observation relation under the stated fixed inputs. Evidence: source branch derivation plus tests.md; unexercised branches remain hypotheses. Oracle: evaluate the scoped actual helper on admissible fixtures and compare this observation. No universal proof.

### size_bound

Empty input produces two bytes; output byte length is 2 plus per-scalar emission lengths.

Operator: specialized observation relation under the stated fixed inputs. Evidence: source branch derivation plus tests.md; unexercised branches remain hypotheses. Oracle: evaluate the scoped actual helper on admissible fixtures and compare this observation. No universal proof.

### transport_gap

Emitted unicode escape for NUL is not reconstructed by json_field, so unrestricted serializer/parser roundtrip is unsupported.

Operator: specialized observation relation under the stated fixed inputs. Evidence: source branch derivation plus tests.md; unexercised branches remain hypotheses. Oracle: evaluate the scoped actual helper on admissible fixtures and compare this observation. No universal proof.

### tests

#### Scoped evidence

Parent native slice and exact names are in `../tests.md`.

json_str fragment is source-derived only; no direct JSON roundtrip assertion. Its unicode-control mismatch with json_field is explicitly unsupported.

This fragment has no independent full-coverage claim. Its byte range and source hash bind the source-derived relation; parent test success is evidence only where that helper is actually reached.

### invariant-and-cost

#### Invariant and cost

O(input UTF-8 bytes plus escaped output), worst six ASCII bytes per control; allocation only.

On completion no raw control scalar below U+0020 occurs between quotes; no file effects.

The complement and specialized catalog constrain preserved coordinates and effect boundaries. Empty/malformed domains are only guaranteed where explicitly admitted. No whole-program cost bound follows from a helper bound.