> at System.ThrowHelper.ThrowArgumentOutOfRangeException(ExceptionArgument argument, ExceptionResource resource)
at System.Collections.Generic.List`1.get_Item(Int32 index)
at ParseTreeVisualizer.VisualizerControl.changeSelection(Object sender)
at ParseTreeVisualizer.VisualizerControl.<.ctor>b__0_5(Object s, RoutedPropertyChangedEventArgs`1 e)
at System.Windows.RoutedPropertyChangedEventArgs`1.InvokeEventHandler(Delegate genericHandler, Object genericTarget)
at System.Windows.RoutedEventArgs.InvokeHandler(Delegate handler, Object target)