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iOS Swift 2.0 Enumerations and Optionals Introduction to Optionals Nil Values in Collections

Paul M
Paul M
16,370 Points
Posted by Paul M
Paul M
16,370 Points

I have no idea what to do on this question, Swift 2.0 Optionals

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.

I have no idea what to do, can someone help me?

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 leadActor = movieDictionary["Spectre": "cast": "Daniel Craig"] {
    var leadActor = movieDictionary[0]
}

1 Answer

Amir Gamil
Amir Gamil
5,657 Points
Amir Gamil
Amir Gamil
5,657 Points

Ok what it is essentially asking you to is too find the lead actor. Since it says it is in position 0 in the array, it is referrring to Danel Craig. You need to unwrap each individual stage, first Spectre and then cast using something like this guard let movie = movieDictionary["Spectre"], let people = movie["cast"] You do the same thing for daniel craig.