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

Arius Eich
Arius Eich
2,769 Points
Posted by Arius Eich
Arius Eich
2,769 Points

What are they looking for?

I do not understand what this code challenge is looking for? Is it the initializer statement that the function needs to be in? Do they even want this function to be created? Why do I get an error?

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

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

            return Book(title: title, author: author, price: price, pudDate: pudDate)
        }
        }
}

1 Answer

Everton Carneiro
Everton Carneiro
15,994 Points
Everton Carneiro
Everton Carneiro
15,994 Points

You don't need to create a function inside the failable init method. Just make title and author return nil since they are not optionals and then assign to the stored properties as usual. Then assign also the two optionals values to their respective stored properties.

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"]

    }

}