iOS Closures in Swift Closure Expressions Using Closure Expressions

Jobelle Galvan
Jobelle Galvan
2,383 Points

what is wrong with my code, I had a bummer says "try and use trailing closure" which I already did.

what is wrong with my code, I had a bummer says "try and use trailing closure" which I already did.

closures.swift
func double(_ i: Int) -> Int {
    return i * 2
}

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

let numbers = [1, 2, 3, 4]

numbers.map({(_ value: Int) -> Int in return value * 2})

numbers.map({value in return value * 2})

numbers.map({value in value * 2})

numbers.map({$0 * 2})

numbers.map(){ $0 * 2 }

numbers.map {$0 * 2}