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

Bruce G
Bruce G
5,360 Points

Problem with network challenge

For some reason I keep getting an error that I don't have the correct syntax. Any help in finding it?

Callbacks.swift
import Foundation

// Add your code below
typealias BlogPostCompletion = (data: NSData, http: NSURLResponse, error: NSError) -> Void

func fetchTreehouseBlogPosts(completion: BlogPostCompletion) {


}
Nathan Bivens
Nathan Bivens
14,460 Points

I'm having trouble as well. I have the exact code. When you look in the preview, it doesn't have an error.

Help would be great.

1 Answer

Nathan Bivens
Nathan Bivens
14,460 Points

Figured it out although I'm confused as to why that set parentheses is needed.

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

func fetchTreehouseBlogPosts(completion: BlogPostCompletion) {

}