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

Adam Petritsis
Adam Petritsis
2,942 Points
Posted by Adam Petritsis
Adam Petritsis
2,942 Points

What am i doing wrong in this exercise?

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.

optionals.swift 
let movieDictionary = ["Spectre": ["cast": ["Daniel Craig", "Christoph Waltz", "LÊa Seydoux", "Ralph Fiennes", "Monica Bellucci", "Naomie Harris"]]]

var leadActor: String = ""

// Enter code below

if let movieTitle = movieDictionary["Spectre"], let leadActor = movieTitle["cast"] {
print(leadActor[0])
}

1 Answer

Kyle Melton
Kyle Melton
6,664 Points
Kyle Melton
Kyle Melton
6,664 Points

Your local if variable and the super variable both have the same name.

Adam Petritsis
Adam Petritsis
2,942 Points
Adam Petritsis
Adam Petritsis
2,942 Points

I don't think that solves the exercise. I'm guessing it has to do with the use of var leadActor somehow.

Kyle Melton
Kyle Melton
6,664 Points
Kyle Melton
Kyle Melton
6,664 Points

"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."

You are printing the answer instead of assigning the value. If you change your local variable to something like leadActorArray. Then assign the 0 position to the goal variable leadActor inside of your if statement. That will solve this challenge.

Kyle Melton
Kyle Melton
6,664 Points
Kyle Melton
Kyle Melton
6,664 Points

Yay! Glad I could help. Good luck! ?