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jiranan supawong
5,716 PointsPlease help me pass this quiz
Your task is to extend the String type and add a method that lets you add an integer value to the string. For example: "1".add(2) If the operation is possible, return an integer value. If the string does not contain an integer and you cannot add to it, return nil.
They said "Bummer! Make sure you're adding method that takes an int and return int"
The challenge is to return nil if the string does not contain an integer. Am i missing anything here?
// Enter your code below
extension String {
func add(number: Int) -> Int! {
guard let total: Int = Int(self)! + number else {
return nil
}
return total
}
}
1 Answer
Alexander Smith
10,476 PointsI made it like this...
extension String {
func add(number: Int) -> Int? {
guard let convertedNumber = Int(self) else{
return nil
}
return convertedNumber + number
}
}
instead of force unwrapping i used the ? marker so able to return the nil