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

Posted by Jairo Bambang Oetomo
Jairo Bambang Oetomo
5,736 Points

What's wrong with this closure?

I think I got it right but it still tells me to check the syntax... :(

Callbacks.swift 
import Foundation

// Add your code below

typealias BlogPostCompletion = (data: NSData!, response: NSURLResponse!, error: NSError!) -> Void

func fetchTreehouseBlogPosts(completion: BlogPostCompletion) {
}
Roberta Voulon
Roberta Voulon
5,792 Points
Roberta Voulon
Roberta Voulon
5,792 Points

What made it work for me in the end was wrap the signature in outer parenthesis like this:

typealias BlogPostCompletion = ((NSData!, NSURLResponse!, NSError!) -> Void)
func fetchTreehouseBlogPosts(completion: BlogPostCompletion) {}

It's really silly, I was stuck on this for days, I didn't even know this is correct syntax, and they're not necessary!