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

Andy Alleyne
Andy Alleyne
2,509 Points
Posted by Andy Alleyne
Andy Alleyne
2,509 Points

May I get the answer to Challenge task 1 of 1 within the initializing optional values lesson?

what is wrong with the below that does not allow me to compile the code. The compiler gives an error but does not give suggestions. The error says that only a valid instance or nil can be returned.

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

 init?(dict: [String : String]){

  guard let myTitle = dict["title"], let myAuthor = dict["author"] else {
  return nil
  }
  self.title = myTitle
  self.author = myAuthor
  self.price = dict["price"] 
  self.pubDate = dict["pubDate"] 
  return nil
 }

}

1 Answer

Niilo Pirttijärvi
PLUS
Niilo Pirttijärvi
Courses Plus Student 2,354 Points
Niilo Pirttijärvi
Niilo Pirttijärvi
Courses Plus Student 2,354 Points

// Heres an answer that passed the challenge.

init?(dict: [String : String]){

    guard let myTitle = dict["title"], let myAuthor = dict["author"] else {
        return nil
    }
    self.title = myTitle
    self.author = myAuthor
    self.price = dict["price"]
    self.pubDate = dict["pubDate"]
}

// I think the "return nil" part of your code was unnecessary.