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

Sean Wilson
Sean Wilson
2,572 Points
Posted by Sean Wilson
Sean Wilson
2,572 Points

Coding challenge failing with working code (tested in Xcode)

The code attached to this post is failing with 'compiler errors' in the online editor. However, no compiler errors are shown in the output.txt.

I've tested this code in Xcode and it compiles and functions correctly.

I'm not sure what to change to get this coding challenge to 'pass'. I've also tested with the 'if let' statement, just in case 'guard' hadn't been accounted for in the solution, however, that failed as well.

Can anyone help?

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

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

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

}

1 Answer

David Papandrew
David Papandrew
8,386 Points
David Papandrew
David Papandrew
8,386 Points

Hi Sean,

Your code is correct as you say, so you won't be happy about the one little hiccup that is preventing your code from passing...

The challenge wants the initializer argument to be called "dict" and doesn't seem to like that you named it "book". So change your init code accordingly:

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"]
    }

Should pass once you do this. Hope that helps.

Sean Wilson
Sean Wilson
2,572 Points
Sean Wilson
Sean Wilson
2,572 Points

Thanks, David! I really should go to bed earlier - perhaps I would have caught that in the description with fresher eyes. :-)

Much appreciated!