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iOS

Posted by Allen Soberano
Allen Soberano
13,634 Points

Stuck on Closures Part 3 of challenge

Hoping someone can point me in the right direction:

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

func removeVowels(from word: String) -> String {
    let vowels = ["a", "e", "i", "o", "u"]
    var newString = ""
    for char in word.characters {
        let lowercaseChar = String(char).lowercased()
        if vowels.contains(lowercaseChar) == nil {
            newString += lowercaseChar
        }

    }
    return newString
}

let helloString = "Hello World!"
helloString.transform(removeVowels(from: helloString)

2 Answers

Jeff McDivitt
Jeff McDivitt
23,970 Points
Jeff McDivitt
Jeff McDivitt
23,970 Points

This is how I did it, but there are probably better ways

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
}

"Hello, World!".transform(removeVowels)
Allen Soberano
Allen Soberano
13,634 Points

Thanks, It was the last line I wasn't sure about how to implement. I was trying to figure out a way to use enums but ended up with this as my final code:

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

func removeVowels(from word: String) -> String {

    let vowels = ["a", "e", "i", "o", "u"]
    var newString = ""

    for char in word.characters{
        if vowels.contains(String(char).lowercased()) == nil {
            newString += String(char)  
        }
    }
    return newString
}

"Hello, World!".transform(removeVowels)
Jeff McDivitt
Jeff McDivitt
23,970 Points
Jeff McDivitt
Jeff McDivitt
23,970 Points

Allen Soberano I like the way you handled it, it is much cleaner

Allen Soberano
Allen Soberano
13,634 Points

Thanks Jeff! Would like to figure out using enums.