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iOS Closures in Swift 2 First Class Functions Higher Order Functions

Ronit Mankad
Ronit Mankad
12,166 Points

Unknown Error!

Idk What I am doing wrong here. Help plz

functions.swift
// Enter your code below
extension String {
 func modify(arg: String -> String) -> String {
   return modify(arg)
 }
}

func firstLetter(value: String) -> String{
 let chr = value[value.startIndex]
    return "\(chr)"
}

let value = "Swift".modify(firstLetter)

1 Answer

David Lin
David Lin
35,864 Points

Almost ... you need to pass in self to your parameter function arg ...

// Enter your code below
extension String {
 func modify(arg: String -> String) -> String {
   return arg(self)
 }
}
Ronit Mankad
Ronit Mankad
12,166 Points

Thanks it solved the problem!

David Lin
David Lin
35,864 Points

You're welcome! good to hear :-)