pulp::state::UndoManager Class Reference

Manages undo/redo history with configurable depth. More...

#include <undo_manager.hpp>

Public Member Functions
void	perform (std::unique_ptr< UndoAction > action)
	Perform an action and add it to the undo history.
void	add_without_executing (std::unique_ptr< UndoAction > action)
	Perform an action without immediately executing it.
void	begin_transaction (const std::string &name)
	Begin a transaction — all subsequent perform() calls are grouped.
void	end_transaction ()
	End the current transaction and push it to the undo stack.
void	cancel_transaction ()
	Cancel the current transaction (discard without pushing).
bool	undo ()
	Undo the most recent action/transaction.
bool	redo ()
	Redo the most recently undone action/transaction.
bool	can_undo () const
	Check if undo is available.
bool	can_redo () const
	Check if redo is available.
std::string	undo_name () const
	Get the name of the next undo action (for menu display).
std::string	redo_name () const
	Get the name of the next redo action.
int	undo_count () const
	Number of undo steps available.
int	redo_count () const
	Number of redo steps available.
void	clear ()
	Clear all undo/redo history.
void	set_max_history (int max)
	Set maximum undo history depth. Oldest entries are discarded.
int	max_history () const
void	set_coalesce_window (std::chrono::milliseconds window)
	Time-window coalescing.
std::chrono::milliseconds	coalesce_window () const

Public Attributes
std::function< void()>	on_state_changed
	Called whenever the undo/redo state changes.

Detailed Description

Manages undo/redo history with configurable depth.

Supports single actions, transaction grouping (begin/end), and named action descriptions for menu display.

UndoManager undo;
undo.set_max_history(100);
 
// Simple action
undo.perform(UndoAction::create("Change color",
    [=] { set_color(old_color); },
    [=] { set_color(new_color); }));
 
// Transaction (multiple actions as one undo step)
undo.begin_transaction("Move and resize");
undo.perform(UndoAction::create("Move", undo_move, redo_move));
undo.perform(UndoAction::create("Resize", undo_resize, redo_resize));
undo.end_transaction();
 
undo.undo();  // undoes entire "Move and resize"
undo.redo();  // redoes entire "Move and resize"

Member Function Documentation

add_without_executing()

void pulp::state::UndoManager::add_without_executing ( std::unique_ptr< UndoAction > action )

inline

Perform an action without immediately executing it.

Use when you've already applied the change.

begin_transaction()

void pulp::state::UndoManager::begin_transaction ( const std::string & name )

inline

Begin a transaction — all subsequent perform() calls are grouped.

can_redo()

bool pulp::state::UndoManager::can_redo ( ) const

inline

Check if redo is available.

can_undo()

bool pulp::state::UndoManager::can_undo ( ) const

inline

Check if undo is available.

cancel_transaction()

void pulp::state::UndoManager::cancel_transaction ( )

inline

Cancel the current transaction (discard without pushing).

clear()

void pulp::state::UndoManager::clear ( )

inline

Clear all undo/redo history.

coalesce_window()

std::chrono::milliseconds pulp::state::UndoManager::coalesce_window ( ) const

inline

end_transaction()

void pulp::state::UndoManager::end_transaction ( )

inline

End the current transaction and push it to the undo stack.

max_history()

int pulp::state::UndoManager::max_history ( ) const

inline

perform()

void pulp::state::UndoManager::perform ( std::unique_ptr< UndoAction > action )

inline

Perform an action and add it to the undo history.

The action's redo function is called immediately.

When set_coalesce_window is non-zero and this call arrives within that window of the previous outside-transaction perform(), the new action is appended to the previous transaction rather than creating a new top-level entry. This produces single-step undo for rapid sequences (e.g., a slider drag).

redo()

bool pulp::state::UndoManager::redo ( )

inline

Redo the most recently undone action/transaction.

redo_count()

int pulp::state::UndoManager::redo_count ( ) const

inline

Number of redo steps available.

redo_name()

std::string pulp::state::UndoManager::redo_name ( ) const

inline

Get the name of the next redo action.

set_coalesce_window()

void pulp::state::UndoManager::set_coalesce_window ( std::chrono::milliseconds window )

inline

Time-window coalescing.

When window > 0, two consecutive perform() calls outside any explicit transaction that arrive within this duration are merged into one undo step. 0 disables (each perform() becomes its own undo step). 0 by default to preserve existing behavior.

set_max_history()

void pulp::state::UndoManager::set_max_history ( int max )

inline

Set maximum undo history depth. Oldest entries are discarded.

undo()

bool pulp::state::UndoManager::undo ( )

inline

Undo the most recent action/transaction.

undo_count()

int pulp::state::UndoManager::undo_count ( ) const

inline

Number of undo steps available.

undo_name()

std::string pulp::state::UndoManager::undo_name ( ) const

inline

Get the name of the next undo action (for menu display).

Member Data Documentation

on_state_changed

std::function<void()> pulp::state::UndoManager::on_state_changed

Called whenever the undo/redo state changes.

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The documentation for this class was generated from the following file:

• /home/runner/work/pulp/pulp/core/state/include/pulp/state/undo_manager.hpp