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

Cody Adkins
Cody Adkins
7,260 Points

Not sure where my error is. Can someone look at my code?

trying to use Swifts Guard statement. Not sure if that has anything to do with it...

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

}

func bookInformation(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) 
}

1 Answer

LaToya Legemah
LaToya Legemah
12,600 Points

The answer is:

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
        }
        self.title = title
        self.author = author
        self.price = dict["price"]
        self.pubDate = dict["pubDate"]
        }    
}

It was answered by Evan Demaris . Please see for more info:

https://teamtreehouse.com/community/creating-a-struct-init-and-accepting-a-dictionary-type