# Undo and restore

Control / history

undo, redo, snapshot, freeze, replay a recorded path

Page: <https://meridian.online/operations/undo-and-restore>

## Status

A feature, not a step.

It lives in how a Protocol runs. [src/history.rs in arcform at fc62d6f](https://github.com/meridian-online/arcform/blob/fc62d6f861dd/src/history.rs)

## Variants

- Freeze or copy a snapshot: Keep a static copy of a sheet or column, with computed cells evaluated to plain values.
- Undo or redo a change: Step back through recent changes, or forward again.

## What other tools call it

Meridian's classification; an independent blind rating agreed on 86.2% of 312 rows (exact class, version 2).

- VisiData: [`dup-rows`](https://github.com/saulpw/visidata/blob/7609212ec2febafa9caba7183cbebfaf49627909/visidata/sheets.py#L1300) (read 2026-09-23)
- VisiData: [`dup-rows-deep`](https://github.com/saulpw/visidata/blob/7609212ec2febafa9caba7183cbebfaf49627909/visidata/sheets.py#L1302) (read 2026-09-23)
- VisiData: [`freeze-col`](https://github.com/saulpw/visidata/blob/7609212ec2febafa9caba7183cbebfaf49627909/visidata/features/freeze.py#L75) (read 2026-09-23)
- VisiData: [`freeze-sheet`](https://github.com/saulpw/visidata/blob/7609212ec2febafa9caba7183cbebfaf49627909/visidata/features/freeze.py#L76) (read 2026-09-23)
- VisiData: [`redo-last`](https://github.com/saulpw/visidata/blob/7609212ec2febafa9caba7183cbebfaf49627909/visidata/undo.py#L134) (read 2026-09-23)
- VisiData: [`setcol-freeze`](https://github.com/saulpw/visidata/blob/7609212ec2febafa9caba7183cbebfaf49627909/visidata/features/freeze.py#L74) (read 2026-09-23)
- VisiData: [`undo-last`](https://github.com/saulpw/visidata/blob/7609212ec2febafa9caba7183cbebfaf49627909/visidata/undo.py#L133) (read 2026-09-23)