BAD_EXC_ACCESS checking to see if data exist:SWIFT - swift

Question

I have a UITableViewController that I have data. If you tap on the row, you can edit the existing data, if you tap on the + in the UIBarButtonItem, you add new infomation. When my Segue passes the Core Data Object (vc.managedObjectID) my "detail" view controller checks to see if the firstName field has data or no data.
In Objective-C, I would do something like this
- (void)refreshInterface
{
CoreDataHelper *cdh = [CoreDataHelper sharedHelper];
Cues *existingCues = (Cues*)[cdh.context existingObjectWithID:_cuesNSManagedObjectID error:nil];
if (!existingCues.cuesName)
{
_cueNameTextField.text = nil;
self.cueDescriptionTextView.text = nil;
}
else
{
_cueNameTextField.text = existingCues.cuesName;
self.cueDescriptionTextView.text = existingCues.cuesDescription;
}
}
I'm having a problem checking to see if there is any data in firstName: var firstName = playerInformation.firstName causes a EXC_BAD_ACCESS only when adding a new object (meaning playerInformatin is empty), when I tap to see existing data it returns the correct data. How do I check to see if playerInfomation is empty (new record) or has data (exisiting data) in Swift?
func refreshInterface(){
if managedObjectID != nil {
var playerInformation = managedObjectContext?.existingObjectWithID(managedObjectID!, error: nil) as? PlayerInformation
var firstName = playerInformation!.firstName //EXC_BAD_ACCESS
println("firstName \(firstName)")
}
}
prepareForSegue
override func prepareForSegue(segue: UIStoryboardSegue, sender: AnyObject?) {
if segue.identifier == "addPlayerInformationDetail" {
println("addPlayerInformationDetail")
let context = self.fetchedResultsController.managedObjectContext
let entity = self.fetchedResultsController.fetchRequest.entity
let playerInformation = NSEntityDescription.insertNewObjectForEntityForName(entity.name, inManagedObjectContext: managedObjectContext!) as PlayerInformation?
var vc = segue.destinationViewController as PlayerInformationDetailTableViewController
vc.managedObjectID = playerInformation?.objectID
} else if segue.identifier == "editPlayerInformationDetail" {
println("editPlayerInformationDetail")
var indexPath:NSIndexPath = tableView.indexPathForSelectedRow()!
var vc = segue.destinationViewController as PlayerInformationDetailTableViewController
vc.managedObjectID = self.fetchedResultsController.objectAtIndexPath(indexPath).objectID
}

Answer 1

You can use a conditional let like so:
if let firstName = playerInformation?.firstName {
println("firstName \(firstName)")
}
This will only unwrap the optional value if it isn't nil, avoiding the crash.

Answer 2

for some reason this works:
var playerInformation = managedObjectContext?.existingObjectWithID(managedObjectID!, error: nil)
var firstName: AnyObject? = playerInformation?.valueForKey("firstName")
println("firstName \(firstName)")
If I subclass the managedObjectContext as PlayerInformation, I would get EXC_BAD_ACCESS