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iOS Build a Weather App with Swift Managing Complexity Callback Methods With Closures

Posted by Alex Curtis
Alex Curtis
8,252 Points

Stumped on Callback Methods With Closures Challenge 1

I typed this code into Playground and am not receiving any errors. Perhaps I am not understanding the question. Any help much appreciated, Thanks!

Callbacks.swift 
import Foundation

typealias BlogPostCompletion = (NSData!,NSURLResponse!, NSError!) -> Void

func fetchTreehouseBlogPosts(completion: BlogPostCompletion) {

}

1 Answer

Michael Zaro
Michael Zaro
13,196 Points

I just ran into this problem and found the answer here

Basically, just wrap (NSData!, NSURLResponse!, NSError!) -> Void in another set of parentheses. Not sure why though, since Pasan doesn't do it in the video and it works perfectly... Oh well, maybe I'm missing something.

typealias BlogPostCompletion = ((NSData!, NSURLResponse!, NSError!) -> Void)

func fetchTreehouseBlogPosts (completion: BlogPostCompletion) {

}
Alex Curtis
Alex Curtis
8,252 Points

Oddly I decided to try this as a shot in the dark and it worked for me as well. I then tried to take the question down but couldn't. Thanks for the response though, hopefully it saves somebody some time.