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iOS Closures in Swift First Class Functions Higher Order Functions

Danny Garcia
Danny Garcia
17,353 Points

Need help with this exercise : Next we need to define a function that we can apply on a String literal to transform it

I tried this function in Xcode an it works. I'm to sure what is going on.

// Enter your code below
extension String {
  func transform(_ operation: (String) -> String) -> String {
    return operation(self)

  func removeVowels(from arg: String) -> String {
    var newString: String = ""
    for char in arg.characters {
      switch char {
        case "a", "A", "e", "E", "i", "I", "o", "O", "u", "U" : continue
    return newString
Adolfo Reyes
Adolfo Reyes
10,599 Points

Did you try adding "Y" to your cases? ... also like the way you use the switch statement, I used an if statement.