Use of hierarchical states
I was wondering if hierarchical states make sense. In the example found here https://code.google.com/p/stateless/ the state OnHold is a substate of Connected. But what does this mean? OnHold permits also the actions permitted by Connected? Not really. For instance OnHold does not support the PlaceOnHold action.
Actually the only use I see is that the OnExit call of Connected will not be executed when call is placed on hold.
Are the any other uses?