Allowing Undo without dirtying NSDocument [Leopard]

[David Dunham]

My Cocoa app had some undoable actions that changed the user's view,  
but shouldn't mark the document as dirty. In Tiger I could use

- (void) undoableActionDoesntDirtyDocument
{
	// This action, while undoable, shouldn't mark the document dirty
	NSDocument*	doc = [[[self window] windowController] document];
	[doc updateChangeCount:[[doc undoManager] isUndoing] ? NSChangeDone :  
NSChangeUndone];
}

but in Leopard, my window gets the dot and the document is considered  
dirty.

How can I make an action undoable without the document thinking a save  
is necessary?

David Dunham     A Sharp, LLC
Voice/Fax: 206 783 7404     http://a-sharp.com
Efficiency is intelligent laziness.