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

The groupant beside math/src/steps.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:** [`math/src/steps.rs`](https://github.com/ElamurAI/mova-free/blob/main/math/src/steps.rs)
- **source SHA-256:** `e5cb6a8faf439e29…`
- **covers:** ignore_set v1 collects real quantities lacking question-context overlap, returning them only if>=2 real quantities remain. v2 uses target head/modifier matches over quantities with units; returns unmatched unit-bearing indices only if at least1 bound item, a nonempty ignored set and>=2 real survivors. (bytes 57799–62615)
- **part of:** [math-steps](https://md.groupants.elamur.ai/free/en/mova/math/src/steps.rs.groupant/)
- **repository folder:** [`math/src/steps.rs.groupant/binding.groupant`](https://github.com/ElamurAI/mova-free/tree/main/math/src/steps.rs.groupant/binding.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` |
| **descriptant** | present | [descriptant](#descriptant) |
| **invariant** | partial | [invariant](#invariant) |
| **tests** | source review only runtime gap | [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) |
| `modifier_compatibility` | modifier_compatibility | partial source derived model | [modifier_compatibility](#modifier-compatibility) |
| `environment_dispatch` | environment_dispatch | partial source derived model | [environment_dispatch](#environment-dispatch) |

## Model text


### descriptant

#### math-steps-binding

ignore_set v1 collects real quantities lacking question-context overlap, returning them only if>=2 real quantities remain. v2 uses target head/modifier matches over quantities with units; returns unmatched unit-bearing indices only if at least1 bound item, a nonempty ignored set and>=2 real survivors.

Epoch 2026-10-31: replaced duplicate catalog sentences with concrete exclusions, compatible-antecedent examples and two distinct scoped behavioral views. Source and prior execution evidence are unchanged; this revision ran no tests.

### approximant

#### Scoped forward relation

ignore_set v1 collects real quantities lacking question-context overlap, returning them only if>=2 real quantities remain. v2 uses target head/modifier matches over quantities with units; returns unmatched unit-bearing indices only if at least1 bound item, a nonempty ignored set and>=2 real survivors.

This source-derived relation is partial; no executable percentage surrogate or replacement is supplied.

### invariant

#### Scoped domain and invariants

Returned indices belong to real input quantities. Ignore selection is a heuristic feature/selection boundary, not proof that excluded numbers are irrelevant.

##### Cost

Membership checks repeatedly scan target/modifier/context lists; collecting bound/ignored indices uses Vec::contains. Training BindModel separately costs epochs*items*features and is not executed here.

### models

### behavior_complement

A const-prefixed index cannot enter the returned ignore set. A result leaving fewer than2 real quantities is excluded. Missing-unit quantities in v2 cannot be ignored merely for lacking a unit.

### reverse_reconstruction

With two bound apples plus one orange, [orange_index] can result for many subject/verb/number values. An empty set admits no targets, no unmatched units, or the survivor-count gate failing; it does not identify the reason.

### modifier_compatibility

v2 treats empty target modifiers or empty description modifiers as compatible; otherwise any shared modifier suffices. It does not demand full modifier-set equality.

### environment_dispatch

MATH_IGNORE_V=1 selects context-overlap v1; all other values use v2. Identical Prob can yield different ignore sets under these environments; constants are excluded in both.

### tests

#### Scoped evidence

Static source review only; no ignore_set or BindModel execution.

Named actual source fixtures: none.

Parent tests.md records commands and paired profiles. No additional coverage inferred from parent fixtures outside this byte range; source-scoped numeric/parse properties remain partial.