Welcome to the Treehouse Community

Want to collaborate on code errors? Have bugs you need feedback on? Looking for an extra set of eyes on your latest project? Get support with fellow developers, designers, and programmers of all backgrounds and skill levels here with the Treehouse Community! While you're at it, check out some resources Treehouse students have shared here.

Looking to learn something new?

Treehouse offers a seven day free trial for new students. Get access to thousands of hours of content and join thousands of Treehouse students and alumni in the community today.

Start your free trial

iOS Swift 2.0 Enumerations and Optionals Introduction to Optionals Initializing Optional Values

Posted by Elijah Florence
Elijah Florence
Courses Plus Student 3,225 Points

I am lost

Am I even close?

optionals.swift 
struct Book {
    let title: String
    let author: String
    let price: String?
    let pubDate: String?

   init?(dict: [String : String])
    {
    guard let self.title = dict["title"], let self.author = dict["author"], let self.price = dict["price"], let self.pubDate = dict["pubDate"]
    else { return nil }

}

}

1 Answer

Jesse Anderson
.a{fill-rule:evenodd;}techdegree
Jesse Anderson
iOS Development Techdegree Student 9,702 Points

You are very close! The guard is to check that the constants that are not options actually exist. If they don't, your returning nil. With that in mind, your also doing an init statement, so you need to finish assigning these values after you verify the constants with the guard statement. I don't think you need the price in the guard as that is an optional. And then don't forget your actual assignments.

struct Book {
    let title: String
    let author: String
    let price: String?
    let pubDate: String?

    init?(dict: [String:String]) {
        guard let title = dict["title"], let author = dict["author"] else {
            return nil
        }

        self.title = title
        self.author = author
        self.price = dict["price"]
        self.pubDate = dict["pubDate"]
    }    
}
Elijah Florence
Elijah Florence
Courses Plus Student 3,225 Points

Thanks man That makes a lot of sense