Struct UndoStack 

pub struct UndoStack { /* private fields */ }

Standard undo/redo stack with bounded depth.

Lives on the Player struct — single-threaded, only the player command loop touches it. New actions clear the redo stack (standard semantics).

Uses VecDeque so evicting the oldest entry (front) is O(1) instead of the O(n) Vec::remove(0).

Implementations

impl UndoStack

pub fn new() -> Self

pub fn push(&mut self, entry: UndoEntry)

Push an undo entry. Clears the redo stack. Batch entries exceeding MAX_BATCH_SIZE are truncated.

pub fn pop_undo(&mut self) -> Option<UndoEntry>

Pop the most recent undo entry (for Ctrl+Z).

pub fn pop_redo(&mut self) -> Option<UndoEntry>

Pop the most recent redo entry (for Ctrl+Y / Ctrl+Shift+Z).

pub fn push_redo(&mut self, entry: UndoEntry)

Push an entry onto the redo stack (called when undoing).

pub fn push_undo_keep_redo(&mut self, entry: UndoEntry)

Push an entry onto the undo stack without clearing redo (called when redoing).

pub fn can_undo(&self) -> bool

pub fn can_redo(&self) -> bool

pub fn undo_len(&self) -> usize

pub fn redo_len(&self) -> usize

Trait Implementations

impl Debug for UndoStack

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

Formats the value using the given formatter.

impl Default for UndoStack

fn default() -> UndoStack

Returns the “default value” for a type.