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iOS Closures in Swift 2 Building Standard Library Functions Using Flat Map

Posted by Sam Murphy
Sam Murphy
10,469 Points

Need Help on Using Flat Map Code Challenge!

my code is raising an error "Make sure you're assigning the results of flatMap to a constant named flattenedNumbers" how do i fix it??

flatMap.swift 
let numbers = [[1,2,3], [4,5,6], [7,8,9]]
let flattenedNumbers = numbers.flatMap { $0.flattenedNumbers }

1 Answer

David Papandrew
David Papandrew
8,386 Points
David Papandrew
David Papandrew
8,386 Points

Slight change should work (remove the dot notation for $0):

let flattenedNumbers = numbers.flatMap { $0 }
Sam Murphy
Sam Murphy
10,469 Points

thanks!