$Revision$ $Date$ NSUndoManager Foundation/NSUndoManager.h NSObject beginUndoGrouping canRedo canUndo disableUndoRegistration enableUndoRegistration endUndoGrouping forwardInvocation: anInvocation groupingLevel groupsByEvent isRedoing isUndoing isUndoRegisgrationEnabled levelsOfUndo prepareWithInvocationTarget: target redo redoActionName redoMenuItemTitle redoMenuTitleForUndoActionName: actionName registerUndoWithTarget: target selector: aSelector removeAllActions removeAllActionsWithTarget: target runLoopModes setActionName: actionName setGroupsByEvent: flag setLevelsOfUndo: anInt setRunLoopModes: modes undo undoActionName undoMenuItemTitle undoMenuTitleForUndoActionName: actionName undoNestedGroup