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iOS Closures in Swift First Class Functions Higher Order Functions

Aananya Vyas
Aananya Vyas
20,157 Points
Posted by Aananya Vyas
Aananya Vyas
20,157 Points

Let's use the two functions we created on a String literal.

Bummer! Make sure you call transform on a string literal and assign the result to the result constant i can not figure out why the function call doesnt work!

functions.swift 
extension String{

    func transform(_ argument : (String) -> String) -> String {
        return  argument(self)
    }
}

func removeVowels(from value: String) -> String {
    var output = ""

    for char in value.characters {
        if !(char == "a" || char == "A" || char == "e" || char == "e"
            || char == "i" || char == "I" || char == "o" || char == "O"
            || char == "u" || char == "U") {
            output.append(char)
        }
    }
    return output
}

let result = transform(removeVowels(from: Hello World))

1 Answer

Heidi Puk Hermann
Heidi Puk Hermann
33,366 Points
Heidi Puk Hermann
Heidi Puk Hermann
33,366 Points

Don't know if you have solved it yet... But you have forgotten to put your double quotations around your string and the call should be written like this:

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