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

My code compiles in Xcode but doesn't compile in the editor. What discrepancies do the two editors have?

I do not get any compilation errors. Only a message that says that compilation has failed and that I should click preview for details. However, clicking preview displays a blank page. Please see my code for details.

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

  init?(dictionary: [String: String]) {
    guard let dictTitle = dictionary["title"], let dictAuthor = dictionary["author"] else {
      return nil
    }
    price = dictionary["price"]
    pubDate = dictionary["pubDate"]
    title = dictTitle
    author = dictAuthor
  }
}

1 Answer

David Papandrew
David Papandrew
8,386 Points

The challenge wants the dictionary argument to be named "dict". Make this change and the code should pass.

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

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

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