Question

I have a IsAuthenticated method which has a complex argument type (I copied it from play2’s zentasks example):

def IsAuthenticated(f: => String => Request[AnyContent] => Result): Action[(Action[AnyContent], AnyContent)] =
  Security.Authenticated(username, onUnauthorized) { userId =>
    Action { implicit request =>
      val email = request.session("user.email")
      f(email)(request)
    }
  }

In order to use it, my action is:

def delete(id:String) = IsAuthenticated { email => request =>
   ...
}

You can see I have to declare email event if I don’t need to use it. I can use _ instead:

def delete(id:String) = IsAuthenticated { _ => _ =>
   ...
}

But _ => _ => is still boring.

How to refactor the method to let it’s usage simpler? e.g. If I don’t need email and request, I can:

def delete(id:String) = IsAuthenticated {
   ...
}

If I just need request, I can:

def delete(id:String) = IsAuthenticated { request =>
   ...
}

If I need email, then I declare them all:

def delete(id:String) = IsAuthenticated { email => request =>
   ...
}

Answer 1

You can overload the IsAuthenticated to provide the different flavours you need. For example:

def IsAuthenticated(result: => Result) = IsAuthenticated { _ => _ => result }

You can then use it as follows:

def delete(id:String) = IsAuthenticated {
   ...
}