Difference Between Scala Features and C ++ Concepts

Question

What is the difference between Scala features of a Haskell class type and C ++ 0x concepts?

Like in this example below, where the Observer declares the abstract members of receiveUpdate. The observer is actually an "anonymous" type or structural types.

package observer
trait Subject {
   type Observer = { def receiveUpdate(subject: Any) }
   private var observers = List[Observer]()
   def addObserver(observer:Observer) = observers ::= observer
   def notifyObservers = observers foreach (_.receiveUpdate(this))
}

Answer 1

• Concepts do not come to C ++ 0x, they were removed in the latest versions of the project specification.
• , ( , "forall x , x ..." ) ad-hoc- ad-hoc.
• , ++. ++.
• - .

, - , , -. : ++ Haskell