This is a sample program that shows the "coalesced undo" as discussed in the MacEdition article "Undology 101".

Some things of note:

• Watch your console log (or the terminal if you run the program from the terminal to see the work that's being done undo-wise


• With Coalesce Undo off, drag the slider or the color well for a long period of time, and see how long the undo/redo takes as each of the drags gets replayed. You might want to run 'top' in a terminal window and see what happens to your memory size


• With Coalesce Undo on, the value displayed while dragging the slider or the color chooser grows parenthesis (e.g. (23) and (42)). This shows that a temporary value (outside of the undo recording mechanism) is being displayed during tracking. Once the tracking stops, the actual undoable operation is performed