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iOS Closures in Swift 2 First Class Functions Higher Order Functions

Akshay Kalbhor
Akshay Kalbhor
Courses Plus Student 725 Points

firstLetter function in Challenge Task 2 of 3

I am not sure how to implement the firstLetter function

// Enter your code below
extension String {
   func modify(aFunction: String -> String) -> String {
        return aFunction(self)

func firstLetter(aString: String) -> String {
    return aString.characters.first

1 Answer

Helgi Helgason
Helgi Helgason
7,599 Points

You need to use string interpolation to return the character as a string!