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iOS

Posted by Herman Kwan
Herman Kwan
5,062 Points

Enumerations and Optionals Last Challenge

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

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


    self.title = "title"
    self.author = "author"
    self.price = "price"
    self.pubDate = "pubDate"

}

}

I dont' understand why is this wrong? I did the failable initiator for ["String: String"] and also used the guard to check if author and title has values, if it doesn't return nil. If it does then continue on. What am I doing wrong here?

1 Answer

Mitch Little
Mitch Little
11,870 Points
Mitch Little
Mitch Little
11,870 Points

Hi Herman,

You are almost there!

The solution looks something like this:

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

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

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

You have your guard statements implemented correctly, checking for nil for title and author. However when assigning the dictionary input to the stored properties, in your solution you are essentially hard coding string values which isn't what the challenge is asking.

Take a look at the correct solution and see if you can work out where and how you have gone a little wrong. If you have any questions, feel free to reply!

All the best,

Mitch