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

Ian Henderson
Ian Henderson
5,512 Points
Posted by Ian Henderson
Ian Henderson
5,512 Points

Tried challenge w/ 2 different coding approaches that both work in XCode. Both cases get "could not be compiled" error.

The error says to check "preview" for compiler errors, but in both cases there is no text in the "preview" view. One approach is attached, the other is as follows:

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

if let movieName = movieDictionary["Spectre"], let movieTeam = movieName["cast"] { var leadActor: String = movieTeam[0] }

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

if let movieName = movieDictionary["Spectre"] , let leadRole = movieName["cast"]{
    var leadActor: String = leadRole[0]
}

1 Answer

Jorge Solana
Jorge Solana
6,064 Points
Jorge Solana
Jorge Solana
6,064 Points

Hey Ian

Variable leadActor is already written on top of the code challenge, so you don't need to define it again in the if let section. Xcode works because it should declare a local variable to the if statement.

Other than that, I don't see any other issue.

Keep up the good work!