How to use completionHandler Closure with return in Swift?

Question

I am trying to us a RESTful API that returns some json data. I want to encapsulate the code that creates the HTTP Request and sets the headers in its own method so I can cal

Answer 1

The completion handler can't return anything because the closure you have to supply has to be of return type Void and not AnyObject!.

func dataTaskWithRequest(_ request: NSURLRequest!,
   completionHandler completionHandler: ((NSData!,
                              NSURLResponse!,
                              NSError!) -> Void)!) -> NSURLSessionDataTask!