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![Jobelle Galvan](https://secure.gravatar.com/avatar/c5935cfc57bf791c96862e045dae5e3b?s=96&d=https%3A%2F%2Fecs-static.teamtreehouse.com%2Fassets%2Fcontent%2Fdefault_avatar-445fbbabfc8dc9188fb5967fe43322ee0c3e0dd1e10f378bf8343784af5a13eb.webp&r=pg)
Jobelle Galvan
3,126 Pointswhat 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.
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}
1 Answer
![Caleb Kleveter](https://uploads.teamtreehouse.com/production/profile-photos/1513202/micro_caleb.jpg)
Caleb Kleveter
Treehouse Moderator 37,862 PointsSorry it took me so long to get to this, my fault.
All you need to do to pass the challenge is to modify the existing code on this line:
let doubledValues = [1,2,3,4].map(doubler)
You should change the call to the map
method so you use a trailing closure and the auto-generated parameter name.