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iOS Build a Simple iPhone App with Swift Getting Started with iOS Development Swift Recap Part 1

Posted by Mike Ernest
Mike Ernest
22,680 Points

Code cannot be compiled... Not sure why??

I cannot for the life of me figure this code challenge out. However, when I paste this code into an Xcode playground it seems to work fine. What am I missing?

structs.swift 
struct Tag {
  let name: String
}


struct Post {
  let title: String
  let author: String
  let tag: Tag

  init(title: String, author: String, tag: String) {
    self.title = title
    self.author = author
    self.tag = Tag(name: tag)
  }

  func description() -> String {
    return "\(title) by \(author). Filed under \(tag.name)"
  }

}

let firstPost = Post(title: "iOS Development", author: "Mike Ernest", tag: "swift")
let postDescription = firstPost.description()

2 Answers

Dan Lindsay
Dan Lindsay
39,611 Points

Hey Mike,

The challenge doesn’t ask for an init method, and yours has tag being type String, when it should be of type Tag . Also, when you created your firstPost constant, you didn’t create the proper Tag

So to pass the first part of the challenge, this will work:

struct Tag {
  let name: String
}
struct Post {
  let title: String
  let author: String
  let tag: Tag
}

let firstPost = Post(title: "iOS Development", author: "Mike Ernest", tag: Tag(name: "swift"))

For the second part of the challenge, your description method is perfect, so nothing need to change there. Same for your postDescription constant. So this code will pass:

struct Tag {
  let name: String
}
struct Post {
  let title: String
  let author: String
  let tag: Tag

func description() -> String {
    return "\(title) by \(author). Filed under \(tag.name)"
  }

}

let firstPost = Post(title: "iOS Development", author: "Mike Ernest", tag: Tag(name: "swift"))
let postDescription = firstPost.description()

While you don’t need the init method to pass the challenge, this one added to Post will still pass the challenge:

struct Post {
    var title: String
    var author: String
    var tag: Tag

    init(title: String, author: String, tag: Tag) {
        self.title = title
        self.author = author
        self.tag = tag
    }

    func description() -> String {
        return "\(title) by \(author). Filed under \(tag.name)"
    }
}

Hope this helps!

Dan

Mike Ernest
Mike Ernest
22,680 Points

Thanks so much for taking the time to explain this. Really helpful and I understand where I went wrong.

kjvswift93
kjvswift93
13,515 Points
kjvswift93
kjvswift93
13,515 Points

The issue here is that the challenge doesn't ask you to create a custom initializer method.

struct Tag {
  let name: String
}

struct Post {
    var title: String
    var author: String
    var tag: Tag

    func description() -> String  {
        return "\(title) by \(author). Filed under \(tag.name)"
    }

}

let myTag = Tag(name: "Classics")
let firstPost = Post(title: "1984", author: "George Orwell", tag: myTag)
let postDescription = firstPost.description()
Mike Ernest
Mike Ernest
22,680 Points

Thanks, Kyle! Very helpful.