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

ziakarim
ziakarim
20,779 Points
Posted by ziakarim
ziakarim
20,779 Points

Error?

What is the error in the code below? Compiles in a playground, but not on treehouse. thx!

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

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

    self.title = title
    self.author = author
}

}

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

}

1 Answer

Florin Veja
Florin Veja
6,912 Points

Zia,

I believe the Dictionary definition as Dictionary<String, String> was the issue. I changed that to [String: String] and that passed.

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

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

        self.title = title
        self.author = author
    }
}

Let me know if that works for you!

Florin

ziakarim
ziakarim
20,779 Points
ziakarim
ziakarim
20,779 Points

Great, thanks Florin!