Struct UndoHistorySnapshot 

pub struct UndoHistorySnapshot {
    pub format_version: u32,
    pub undo_stack: Vec<UndoHistoryStep>,
    pub redo_stack: Vec<UndoHistoryStep>,
    pub max_undo: usize,
    pub clean_index: Option<usize>,
    pub next_group_id: usize,
    pub open_group_id: Option<usize>,
}

A persistable snapshot of the undo/redo history for a single document.

This is intended for “hot exit” workflows: persist the editor text plus this snapshot, then restore both on startup so undo/redo keeps working across restarts.

Notes:

• This snapshot does not include the current document text; callers are responsible for persisting/restoring the text separately.
• Restoring a snapshot into a different document text will produce undefined undo behavior.

Fields

format_version: u32

Snapshot format version for forward compatibility.

undo_stack: Vec<UndoHistoryStep>

Undo steps (oldest → newest).

redo_stack: Vec<UndoHistoryStep>

Redo steps (oldest → newest).

max_undo: usize

Configured maximum undo history depth.

clean_index: Option<usize>

Clean point tracking in the linearized history (index into undo_stack + redo_stack).

next_group_id: usize

The next group id to allocate.

open_group_id: Option<usize>

Currently open coalescing group id, if any.

Trait Implementations

impl Clone for UndoHistorySnapshot

fn clone(&self) -> UndoHistorySnapshot

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for UndoHistorySnapshot

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl Eq for UndoHistorySnapshot

impl PartialEq for UndoHistorySnapshot

fn eq(&self, other: &UndoHistorySnapshot) -> bool

Tests for self and other values to be equal, and is used by ==.

fn ne(&self, other: &Rhs) -> bool

Tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

impl StructuralPartialEq for UndoHistorySnapshot