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iOS Enumerations and Optionals in Swift Introduction to Optionals Nil Values in Collections

I'm not sure why it is not working

In the editor, you have a pretty complex dictionary representing a movie. It contains a nested dictionary, which itself contains an array of Strings as a value.

Your job is to assign the string containing the value for the lead actor (which for the sake of the example is at position 0 in the array) to the variable leadActor.

Since dictionaries return optional values, you will have to use an if let statement to unwrap each consecutive operation.

What I'm I doing wrong hear

let movieDictionary = ["Spectre": ["cast": ["Daniel CraThe ig", "Christoph Waltz", "Léa Seydoux", "Ralph Fiennes", "Monica Bellucci", "Naomie Harris"]]]

var leadActor: String = ""

// Enter code below

if let movie = movieDictionary["Spectre"], let cast = movie["cast"], let lead = cast[0] {
  leadActor = lead

1 Answer

Paul Brazell
Paul Brazell
14,371 Points

2 things of note here.

First, I think you may have accidentally modified the movie dictionary value for "Daniel Craig". You may want to fix that first.

Secondly, I would suggest copying the code any pasting it into a playground in Xcode. I think the compiler error in there will lead to the answer you are looking for.

Hint: What does an if let statement unwrap?