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iOS

Nadia Bluhm
Nadia Bluhm
2,124 Points

Enumeration and Optionals in Swift 3, Challenge Task 1 of 1, What am I doing Wrong?

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

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

Joshua Hardy
Joshua Hardy
17,204 Points

Which lesson is this from?

Nadia Bluhm
Nadia Bluhm
2,124 Points

This is from Introduction to Optionals : Initializing optional values.

Joshua Hardy
Joshua Hardy
17,204 Points

For future reference, place ``` (beside the key) on the line before your code and the line after your code so that it will appear in the right format. It makes it easier to read.

1 Answer

Joshua Hardy
Joshua Hardy
17,204 Points
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"]

    }

}
Nadia Bluhm
Nadia Bluhm
2,124 Points

Thanks! Now I understand the guard statement. Had to rewatch the lesson..

Otto linden
Otto linden
5,857 Points

Why do we say: dict["title"] and not Book["title"]?