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iOS Closures in Swift 2 Closure Expressions Using Closure Expressions

Ronny Setiawan
Ronny Setiawan
6,773 Points

Shorthand Syntax

Why this code is still wrong..?

func doubleValue(i: Int) -> Int {
    return i * 2

let doubler = doubleValue
let doubledValues = [1,2,3,4].map(doubler)

[1,2,3,4].map() {$0 * 2}

1 Answer

William Li
William Li
Courses Plus Student 26,868 Points

hi, Ronny, the shorthand notion in your code is fine; but it's supposed be put on the doubledValues let assign line to replace the (doubler), it's not meant to be on its own line.

let doubler = doubleValue
let doubledValues = [1,2,3,4].map {$0 * 2}

Hope it helps.