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iOS Closures in Swift 2 Closures in Cocoa Touch Using the Networking Code

Posted by Christine Chang
Christine Chang
1,917 Points

Elaboration on purpose of calling a closure within a closure

I'm still not entirely clear on the benefit of passing a closure's arguments to another closure, as below:

let dataTask = session.dataTaskWithRequest(request) {data, response, error in
    // Execute body of closure
    completion(response!)
}

getRecentBlogPost() {response in 
    print(response)
}

Couldn't we have achieved the same thing by directly printing the response in the body of dataTaskWithRequest's completion handler, as below?

let dataTask = session.dataTaskWithRequest(request) {data, response, error in
    // Execute body of closure
    print(response)
}
Roger Antonell
Roger Antonell
18,252 Points
Roger Antonell
Roger Antonell
18,252 Points

Hi Christine,

The Code that you show does exactly the same, but the difference between one approach and the other is that the first always will print the response. the second approach you can specify throw a closure expression what you wanna do with the response ,not just print