Base class with member parameterized on type of extending class

[rcor via Digitalmars-d-learn]

On Monday, 20 October 2014 at 06:17:42 UTC, Jacob Carlborg wrote:
>
> You can always make Scene a template class:
>
> abstract class Scene (T)
> {
>     private StateMachine!T _stateMachine;
> }
>
> class MainMenu : Scene!(MainMenu) {}
>
> But I'm guessing you like to avoid that if possible.

I would, as I need to keep track of the current scene in a 
variable somewhere:

   Scene _currentScene; // problematic if Scene is a template

I could just declare the StateMachine separately in every Scene, 
but that seems like a lot of duplicate code (I then repeat the 
same code for updating the state machine, ect.)