Welcome to the Treehouse Community
Want to collaborate on code errors? Have bugs you need feedback on? Looking for an extra set of eyes on your latest project? Get support with fellow developers, designers, and programmers of all backgrounds and skill levels here with the Treehouse Community! While you're at it, check out some resources Treehouse students have shared here.
Looking to learn something new?
Treehouse offers a seven day free trial for new students. Get access to thousands of hours of content and join thousands of Treehouse students and alumni in the community today.
Start your free trial
mitchellwan
3,620 PointsWhy does my code not work?? Thanks
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.
let movieDictionary = ["Spectre": ["cast": ["Daniel Craig", "Christoph Waltz", "Léa Seydoux", "Ralph Fiennes", "Monica Bellucci", "Naomie Harris"]]]
var leadActor: String = ""
// Enter code below
if let movieCast = movieDictionary["Spectre"], let mainActor = movieCast["cast"] {
var leadActor = mainActor[0]
}
1 Answer
Thomas Oliver Bastable
Python Development Techdegree Graduate 29,026 PointsSo close Mitchell! You're redeclaring leadActor variable inside the if let body - you just need to ditch the var before the leadActor for it to work.
let movieDictionary = ["Spectre": ["cast": ["Daniel Craig", "Christoph Waltz", "Léa Seydoux", "Ralph Fiennes", "Monica Bellucci", "Naomie Harris"]]]
var leadActor: String = ""
// Enter code below
if let movieCast = movieDictionary["Spectre"], let mainActor = movieCast["cast"] {
var leadActor = mainActor[0]
}
mitchellwan
3,620 Pointsmitchellwan
3,620 PointsSo I dont need to mention the var again because I already declared it before, and redeclaring it is causing an error? Thanks!
Thomas Oliver Bastable
Python Development Techdegree Graduate 29,026 PointsThomas Oliver Bastable
Python Development Techdegree Graduate 29,026 PointsYeah, the thing is using var inside the context of the if let declares an entirely new variable with a new memory ref. So you just need to use leadActor as it's been declared before the if let 👍