---
title: "latex-extract-environment — Mova code model"
description: "Mova code model of latex/src/extract.rs: components with their labels, obernants and the model text."
url: "https://groupants.elamur.ai/free/en/mova/latex/src/extract.rs.groupant/environment.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/latex/src/extract.rs.groupant/environment.groupant/>

# latex-extract-environment

The groupant beside latex/src/extract.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:** [`latex/src/extract.rs`](https://github.com/ElamurAI/mova-free/blob/main/latex/src/extract.rs)
- **source SHA-256:** `b717bad28ee0917e…`
- **covers:** begin reads first {env}, searches first exact end; recognized math emits body, closed verbatim suppresses it. Selected environments skip a first braced argument. (bytes 6305–7957)
- **part of:** [latex-extract](https://md.groupants.elamur.ai/free/en/mova/latex/src/extract.rs.groupant/)
- **repository folder:** [`latex/src/extract.rs.groupant/environment.groupant`](https://github.com/ElamurAI/mova-free/tree/main/latex/src/extract.rs.groupant/environment.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 | [approximant](#approximant) |
| **ast** | partial | `../syntax.json` |
| **composition** | partial | [composition](#composition) |
| **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) |
| `argument` | argument | partial source derived model | [argument](#argument) |
| `closer` | closer | partial source derived model | [closer](#closer) |
| `display` | display | partial source derived model | [display](#display) |
| `recovery` | recovery | partial source derived model | [recovery](#recovery) |

## Model text


### descriptant

#### latex-extract-environment

begin reads first {env}, searches first exact end; recognized math emits body, closed verbatim suppresses it. Selected environments skip a first braced argument.

Epoch 2026-10-31: complete sources read before tests/model edits. Partial source-bound modeling; no production optimization or speed claim. Nested fragments share the parent lexical syntax. Caller/callee contracts outside owned files remain delegated.

### approximant

#### Forward relation

begin reads first {env}, searches first exact end; recognized math emits body, closed verbatim suppresses it. Selected environments skip a first braced argument.

#### Domain and executable surrogate gap

Bounded UTF-8 inputs and synthetic local files; supported parser-produced trees and representable arithmetic. Arbitrary public constructors are not certified total. Exact categorical semantics lack a useful percentage surrogate; no executable approximant attachment. Future numerical profiles require an explicit metric, zero case, source/evidence binding and supported 1/2/5/10% cap. Failure/effect differences cannot count as numerical error.

### invariant

#### Invariant

For the scoped transition bytes [6305,7957): begin reads first {env}, searches first exact end; recognized math emits body, closed verbatim suppresses it. Selected environments skip a first braced argument. Unknown environment cannot directly emit Env; missing math end adds bad, missing verbatim end does not.

#### Cost

Closer search linear in remaining bytes per call; repeated unmatched calls can yield quadratic parent work.

Allocation failure, stack exhaustion and unchecked counter overflow have no additional certificate. No timing claim or global error bound.

### composition

#### Composition

begin reads first {env}, searches first exact end; recognized math emits body, closed verbatim suppresses it. Selected environments skip a first braced argument.

For the scoped transition bytes [6305,7957): begin reads first {env}, searches first exact end; recognized math emits body, closed verbatim suppresses it. Selected environments skip a first braced argument. Unknown environment cannot directly emit Env; missing math end adds bad, missing verbatim end does not.

Parser, printer, AST equality, Macros, Rat and evaluator dependencies retain their own contracts. Structural roundtrip is not arithmetic definedness or numeric truth. Exact lexical binding does not prove caller/callee semantics.

### models

### behavior_complement

Unknown environment cannot directly emit Env; missing math end adds bad, missing verbatim end does not.

### reverse_reconstruction

Same env/body/start permits differing prefix whitespace/argument of same byte length; skipped verbatim unrecoverable.

### argument

First } ends skip, no nesting.

### closer

Nested same-name environments not balanced.

### display

Only math env inline.

### recovery

Missing opening brace returns j; missing end returns close+1.


### tests

#### Selected evidence

cargo test -p latex --features math --lib extract::tests

Two debug/two release executions retained matching sorted named outcomes. External wave28 latexbridge receipts retain numeric exits, compiled assertion controls, restoration, feature checks and source-test map. This scope is not exhaustive branch coverage; parent tests may only exercise some child transitions. Frozen VMM DATA/classification/hash subprocess, live corpus, teacher/API, training/GPU excluded. Reexport/feature compilation is separate from runtime semantics.