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

Posted by Evan Hurst
Evan Hurst
13,266 Points

Not sure what is wrong with the closure callbacks challenge! This code compiles just fine!

Receiving the error " Make sure that the syntax is correct!" but I cannot figure out what is wrong!

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

Callbacks.swift 
import Foundation

// Add your code below
typealias BlogPostCompletion = (NSData!, NSURLResponse!, NSError!) -> Void
func fetchTreehouseBlogPosts(completion: BlogPostCompletion) {
}

2 Answers

Aby Abraham
PLUS
Aby Abraham
Courses Plus Student 12,531 Points
Aby Abraham
Aby Abraham
Courses Plus Student 12,531 Points

Missing parenthesis around return types @typealiase declaration

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

func fetchTreehouseBlogPosts (completion: BlogPostCompletion) {

}
Evan Hurst
Evan Hurst
13,266 Points

Thanks! I could have sworn I tried that, but it seems to have worked now. Much appreciated!

Thorsten Herbst
Thorsten Herbst
11,935 Points
Thorsten Herbst
Thorsten Herbst
11,935 Points

I think you have to attach the word "in" after void

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