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

Christopher David
PLUS
Christopher David
Courses Plus Student 20,027 Points

What is wrong with my code for guarding against the optional values?

I'm not sure what I am doing wrong here. Can anyone enlighten me?

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

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

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

}

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

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

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

}

1 Answer

Christopher David
PLUS
Christopher David
Courses Plus Student 20,027 Points

I realized what I was doing wrong. I was reinitializing the variables when I should not have as well as needed temp variables in the guard statement.

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

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

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

} '''