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

Fabian Kaegy
Fabian Kaegy
17,155 Points

Can' seem to figure it out

Tried this in Xcode and there the Compiler didn't complain. So I don't really know how to continue troubleshooting it. The Video doesn't help me out here either

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

if let spectreMovie = movieDictionary["Spectre"], let spectreCast: [String?] = spectreMovie["cast"], let leadActor = spectreCast[0] {
    print(leadActor)
}

1 Answer

Jeremy Conley
Jeremy Conley
16,657 Points

Like it says, you just have to keep working your way into the dictionary unwrapping along the way

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

var leadActor: String = ""


// Enter code below
if let dic = movieDictionary["Spectre"] {
    if let array = dic["cast"] {
      leadActor = array[0]
    }
}
Fabian Kaegy
Fabian Kaegy
17,155 Points

Thank you! The problem was that I tried to unwrap the array of the cast members as well.

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

if let spectreMovie = movieDictionary["Spectre"], let spectreCast = spectreMovie["cast"] { leadActor = spectreCast[0] }

worked