         self.errorImage = errorImage
         imageDownloadData = NSMutableData()
         
-        let URL = NSURL(string: url)
-        
-        if URL == nil {
+        guard let URL = NSURL(string: url) else {
             isLoadingImage = false
             NSLog("Error: malformed URL passed to downloadImageFromURL")
             return
         }
         
         networkSession = NSURLSession.init(configuration:NSURLSessionConfiguration.defaultSessionConfiguration(), delegate: self, delegateQueue: NSOperationQueue.mainQueue())
-        imageURLDownloadTask = networkSession!.downloadTaskWithURL(URL!)
+        imageURLDownloadTask = networkSession!.downloadTaskWithURL(URL)
         
         imageURLDownloadTask?.resume()
         if usesSpinningWheel {

    private var toolTipWhenFinishedWithError: String?
    
    deinit {
        
        cancelDownload()
    }
    

    
    public func URLSession(session: NSURLSession, downloadTask: NSURLSessionDownloadTask, didFinishDownloadingToURL location: NSURL) {
        
        
        imageDownloadData = NSData.init(contentsOfURL: location)
    }
    
