+ /**
+ * Begins the tracking of changes. All changes will
+ * be recorded until stop_tracking() is called.
+ * The change tracking is global and doesn't support nesting.
+ */
+ void start_tracking();
+
+ /**
+ * Ends the tracking of changes without any changes to the settings.
+ */
+ void stop_tracking();
+
+ /**
+ * Ends the tracking of changes, undoing the changes since the
+ * change tracking began.
+ */
+ void undo_tracked_changes();
+