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iOS Closures in Swift 2 First Class Functions Higher Order Functions

Ronit Mankad
Ronit Mankad
12,166 Points
Posted by 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
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
Ronit Mankad
Ronit Mankad
12,166 Points

Thanks it solved the problem!

David Lin
David Lin
35,864 Points
David Lin
David Lin
35,864 Points

You're welcome! good to hear :-)