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iOS Build a Weather App with Swift (Retired) Concurrency Using Our JSON Data

Jason Holt
Jason Holt
10,041 Points
Posted by Jason Holt
Jason Holt
10,041 Points

Value of option type NSURL? not unwrapped.

''let downloadTask: NSURLSessionDownloadTask = ''sharedSession.downloadTaskWithURL(forecastURL, completionHandler: { (location: NSURL!, ''response: NSURLResponse!, error: NSError!) -> Void in

This line of code returns the following error: Value of optional type NSURL? not unwrapped; did you mean to use ! or ?

Adding bangs removes the errors but is this the right thing to do here?

1 Answer

Chris Shaw
Chris Shaw
26,676 Points
Chris Shaw
Chris Shaw
26,676 Points

Hi Jason,

As of Xcode 6.1 this is how NSURL is expected to work, before 6.1 instances of NSURL didn't behave as optionals which meant it was difficult to test against invalid strings whereas now we can test for that, in this course no testing occurs but in a real app you would want to ensure the URL validates before making the request.

Jason Holt
Jason Holt
10,041 Points
Jason Holt
Jason Holt
10,041 Points

Thanks for the info. Just what I was looking for.