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

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

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

let flattenedNumbers = numbers.flatMap { $0 }

thanks!