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

Tarcan Arca
Tarcan Arca
3,572 Points
Posted by Tarcan Arca
Tarcan Arca
3,572 Points

What's wrong with this initializer?

I would like to add a failable initializer in an existing struct called "Book". I don't get what's wrong with my initializer. Can anybody help?

Code is as follows:

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

    func initialize(dict: [String: String]) -> Book? {
        guard let title = dict["title"], author = dict["author"] else {
            return nil
        }

        let price = dict["price"]
        let pubDate = dict["pubDate"]

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

2 Answers

Greg Kaleka
Greg Kaleka
39,021 Points
Greg Kaleka
Greg Kaleka
39,021 Points

Hi Tarcan,

I'm on mobile, so I can't check all your code, but I'm afraid you haven't written a failable initializer at all - you've written a function called initialize. An initializer must be called init, and a failable initializer should just be init?. No need for the func keyword.

Let us know if that works!

Cheers :beers:

Greg

Tarcan Arca
Tarcan Arca
3,572 Points
Tarcan Arca
Tarcan Arca
3,572 Points

Thanks for the help, it worked!