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iOS Swift Functions and Optionals Optionals What is an Optional?

what is the wrong here

The search function below returns a name if it is found in the array and an empty string if it is not found. Modify the search function to return an optional instead of just a String. In addition, you have to make sure the function returns a nil if the name is not found in the array.

func search(#name: String) -> String {
    let names = ["Doc","Grumpy","Happy","Sleepy","Bashful","Sneezy","Dopey"]
    for n in names {
        if n == name {
            return n

    return  nil

1 Answer

Chris Shaw
Chris Shaw
26,650 Points

Hi nader,

Your return type of String needs to be an optional, this can be accomplished by simply adding a question mark to the end of the type.

func search(#name: String) -> String? {
  // ...

Happy coding!