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

The groupant beside mlab/src/builtins/table.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:** [`mlab/src/builtins/table.rs`](https://github.com/ElamurAI/mova-free/blob/main/mlab/src/builtins/table.rs)
- **source SHA-256:** `f1b0959092cfcdd3…`
- **covers:** read/write wrappers route through it.fs and contextualize errors. readtable validates file kind before read; readmatrix reads before delimiter validation. datenum accepts string/date components; JSON encodes through fileio; string converts NaN to missing. (bytes 26346–33011)
- **part of:** [mlab-builtins-table](https://md.groupants.elamur.ai/free/en/mova/mlab/src/builtins/table.rs.groupant/)
- **repository folder:** [`mlab/src/builtins/table.rs.groupant/effects.groupant`](https://github.com/ElamurAI/mova-free/tree/main/mlab/src/builtins/table.rs.groupant/effects.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` |
| **cost** | symbolic source derived | [invariant](#invariant) |
| **descriptant** | present | [descriptant](#descriptant) |
| **invariant** | partial | [invariant](#invariant) |
| **tests** | partial bounded parent evidence | [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) |
| `effect_order` | effect_order | partial source derived model | [effect_order](#effect-order) |
| `date_adapter` | date_adapter | partial source derived model | [date_adapter](#date-adapter) |
| `branch_relation` | branch_relation | partial source derived model | [branch_relation](#branch-relation) |
| `resource_cost` | resource_cost | partial source derived model | [resource_cost](#resource-cost) |

## Model text


### descriptant

#### mlab-builtins-table-effects

read/write wrappers route through it.fs and contextualize errors. readtable validates file kind before read; readmatrix reads before delimiter validation. datenum accepts string/date components; JSON encodes through fileio; string converts NaN to missing.

Epoch 2026-10-31: isolated source-bound fragment over bytes [26346,33011); includes no claim beyond this relation. Source hash f1b0959092cfcdd3cbd171a48d252ce4c1e652b1e56ed030c160e7667d8cbb54.

### approximant

#### effects: forward relation

read/write wrappers route through it.fs and contextualize errors. readtable validates file kind before read; readmatrix reads before delimiter validation. datenum accepts string/date components; JSON encodes through fileio; string converts NaN to missing.

Domain: Well-shaped values and finite practical windows; effects delegated to it.fs. Physical filesystem not exercised.

Executable surrogate gap: no measured cheaper implementation with a useful scoped metric is supplied. Categorical/error/effect relations are exact obligations, not percent losses. Future numeric caps only1/2/5/10%.

### invariant

#### effects: invariant and cost

writetable serializes before write, so serialization/options failure excludes write; backend partial writes remain backend contract.

datenum with one matrix >=3 columns uses Y/M/D only; scalar components add hour/minute/second fraction.

Scope-specific cost: O(bytes read/written + parser/serializer work) and backend I/O cost; dates/vector string conversion O(number of cells + rendered bytes).

### models

### behavior_complement

Spreadsheet readtable excludes attempted read; readmatrix empty delimiter may follow successful read. No host FS isolation guaranteed by this module itself.

### reverse_reconstruction

Read output admits every file representation decoded to same table; write result empty does not reconstruct previous filesystem contents.

### effect_order

writetable serializes before write, so serialization/options failure excludes write; backend partial writes remain backend contract.

### date_adapter

datenum with one matrix >=3 columns uses Y/M/D only; scalar components add hour/minute/second fraction.

### branch_relation

read/write wrappers route through it.fs and contextualize errors. readtable validates file kind before read; readmatrix reads before delimiter validation. datenum accepts string/date components; JSON encodes through fileio; string converts NaN to missing.

### resource_cost

O(bytes read/written + parser/serializer work) and backend I/O cost; dates/vector string conversion O(number of cells + rendered bytes).

### tests

#### Evidence boundary

See ../tests.md for the actual selected source test and mutant. These tests sample the file, not every fragment branch. Spreadsheet readtable excludes attempted read; readmatrix empty delimiter may follow successful read. No host FS isolation guaranteed by this module itself. Other branches here are source-derived and unexecuted unless the parent test explicitly calls them.