Example of a lazy loaded synchronous background threaded singleton getter in Swift

lazyasyncgetter

let kGlobalDateFormatterSharedInstance = GlobalDateFormatterModel()

class GlobalDateFormatterModel: NSObject {

    @lazy var defaultDomainDateFormatter: NSDateFormatter = self.initializeDefaultDomainDateFormatter()
    
    class var sharedInstance:GlobalDateFormatterModel {
        return kGlobalDateFormatterSharedInstance
    }
    
    func initializeDefaultDomainDateFormatter() -> NSDateFormatter{
        
        var semaphoreDone: dispatch_semaphore_t = dispatch_semaphore_create(0);

        var formatter: NSDateFormatter?
        
        dispatch_async(dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_DEFAULT, 0), {
            
            formatter = NSDateFormatter()
            
            if let unwrappedFormatter = formatter{
                unwrappedFormatter.dateFormat = kDomainDefaultDateFormatterStyle
                unwrappedFormatter.timeZone = NSTimeZone(name: "GMT")
            }
        
            dispatch_semaphore_signal(semaphoreDone)
        })
        
        dispatch_semaphore_wait(semaphoreDone, DISPATCH_TIME_FOREVER);
                
        return formatter!
    }
    
}

Ridiculously over engineered? You betcha