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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

Why am I getting error message "Make sure you are retrieving the string at index 0 in the nested array?" I think I am.

The following and attached code is retrieving the string in the correct position in the dictionary. I do not understand why I am getting error "Make sure you are retrieving the string at index 0 in the nested array"

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

var leadActor: String = ""

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

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

var leadActor: String = ""

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

1 Answer

Reed Carson
Reed Carson
8,306 Points

by saying "let leadActor = castList[0]" you are declaring a new constant called leadActor inside the scope of that statement. "var leadActor" is still set to "", which is the one you are trying to change