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Randell Pur
4,934 PointsI am not sure why this wont pass
It doesn't show any errors in Xcode, and it says to check the "Preview " but it doesn't show anything in there.
The error I get says:
Bummer: Your code could not be compiled. Please click on "Preview" to view the compiler errors.
struct Book {
let title: String
let author: String
let price: String?
let pubDate: String?
}
func book (bookDictionary: [String : String]) -> Book? {
guard let title = bookDictionary["title"], let author = bookDictionary["author"] else {
return nil
}
let price = bookDictionary["price"]
let pubDate = bookDictionary["pubDate"]
return Book(title: title, author: author, price: price, pubDate: pubDate)
}
3 Answers

Gavin Brown
4,560 Pointscreate an init? method within the struct like this init?(dict[String:String]){ //initialize values here}

Gavin Brown
4,560 Pointsinit?(dict:[String:String]){
if let title = dict["title"], let author = dict["author"]{
let price = dict["price"]
let pubDate = dict["pubDate"]
self.price = price
self.title = title
self.author = author
self.pubDate = pubDate
} else {
return nil
}
}

Wouter Willebrands
iOS Development with Swift Techdegree Graduate 13,121 PointsHi Randell,
You are actually very close, but are missing some pieces.
The assignment requests you to create a failable initializer that accepts a dictionary of type [String : String] as input and initializes all the stored properties. Remember that failable inits methods can return nil and is written as init as Gavin stated.
You correctly wrote your guard statements although in the not within the assignment they want you to use "dict" instead of "bookDictionary".
If you change that part to:
init?(dict: [String: String]) {
guard let title = dict["title"], let author = dict["author"] else {
return nil
}
that part should work. Next is initializing all of the properties inside you struct Book. You can do that by adding:
self.title = title
self.author = author
self.price = dict["price"]
self.pubDate = dict["pubDate"]
}
within your method.
Please let me know if you have any more questions. Good luck!