Swift: Downcast AnyObject to Int

anyobject-to-int.swift

func didReceiveCredit(creditInfo: [NSObject:AnyObject]!) {

 // the following does not work
 var amount: Int = creditInfo["credits"]! as Int
 
 // nor does this
 var amount: Int = Int(creditInfo["credits"]! as NSNumber)
 
 // but this does
 var amount: String = creditInfo["credits"]! as String
 
 // so we can get what we want with this
 var amount: Int = (creditInfo["credits"]! as String).toInt()!

}