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iOS Closures in Swift First Class Functions Higher Order Functions

Closures in swift challenge

I am failing to get the code right.can someone come to my rescue.im stuck on the last part

// Enter your code below
extension String {
  func transform(_ argument: (String) -> String) -> String {
    return argument(self)
func removeVowels(from string: String) -> String {
    var newString = ""
    for character in string.characters {
        if ["a","e","i","o","u"].contains(character) {


    return newString
let result = String.transform(removeVowels(from: "hellow world"))

1 Answer

Jeff McDivitt
Jeff McDivitt
23,970 Points

Hi Axon -

The last part of your code should be this

let result = "Hello, World!".transform(removeVowels)

thank you.you saved my day