// Connect pins
private void CommandConnectPins_CanExecute(object sender, CanExecuteRoutedEventArgs e)
{
ConnectPinsParameters xcp = e.Parameter as ConnectPinsParameters;
e.CanExecute = e.Parameter is ConnectPinsParameters cp &&
GraphUtil.CanConnectNodePins(cp.PinA.Pin, cp.PinB.Pin,
(a, b) => ProjectVM.Instance.ReflectionProvider.TypeSpecifierIsSubclassOf(a, b));
}