Unexpected non-void return value in void function

Question

I am doing the HTTP request and getting response in my func. It return the value of response. I am doing it this way:

NSURLConnection.sendAsynchronousRequest(request, queue: NSOperationQueue.mainQueue()) {(response, data, error) in
        println(NSString(data: data, encoding: NSUTF8StringEncoding))
        stringResponse = NSString(data: data, encoding: NSUTF8StringEncoding) as! String
        if stringResponse == "0" {
            return false
        } else if stringResponse == "1" {
            return true
        } else {
            return false
        }
    }

But on all returns I have error Unexpected non-void return value in void function How to fix this?

You should return out side the closure. Else the calling function should have a closure. — Amit89, May 16 '15 at 18:39
let me guess: that code is written inside another method which has Bool as return type? That will not work because it is an asynchronous request. — luk2302, May 16 '15 at 18:52

score 18 · Accepted Answer · answered May 16 '15 at 18:52

Do this if you want the value after you get response.

func getResponse(completionHandler : ((isResponse : Bool) -> Void)) {

NSURLConnection.sendAsynchronousRequest(request, queue: NSOperationQueue.mainQueue()) {(response, data, error) in
        println(NSString(data: data, encoding: NSUTF8StringEncoding))
        stringResponse = NSString(data: data, encoding: NSUTF8StringEncoding) as! String
        if stringResponse == "0" {
           completionHandler(isResponse : false)
        } else if stringResponse == "1" {
           completionHandler(isResponse : true)
        } else {
           completionHandler(isResponse : false)
        }
    }
}

Now you call it as below from where ever you are calling.

classObject.getResponse {(isResponse) -> Void in 

//Do your stuff with isResponse variable.
}

worked for me. Thanks a lot – Linkon Sid Jan 24 '16 at 13:20 — Linkon Sid, Jan 24 '16 at 13:20

score 0 · Answer 2 · answered May 16 '15 at 18:48

The last parameter of sendAsynchronousRequest is a completion handler with type (NSURLResponse!, NSData!, NSError!) -> Void. Note it doesn't have any return type, so don't return anything.

The completion handler is called by the connection framework, it doesn't need any return type.

It's pretty obscure what you are trying to achieve by that returns but you can't do it this way.

Unexpected non-void return value in void function

2 Answers2

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