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Start your free trialRichard Pitts
Courses Plus Student 1,243 PointsWhat is the correct answer?
I have no clue, but am looking for the correct answer and maybe a little explanation relative to my attempt. Thanks.
// Enter your code below
extension String { add(value: Int) } -> Bool return Int?
1 Answer
David Papandrew
8,386 PointsHi Richard,
You need to create a new method called "add". The method may or may not return an Int. So you are headed in the right direction with your solution above.
In the body of the method, you want to check if a string ("self") calling the add method can be recast as an Integer or not. So you'll use an if statement to do this.
Here's the code:
extension String {
func add(value: Int) -> Int? {
if Int(self) != nil {
return Int(self)! + value
} else {
return nil
}
}
}
And to use the extension:
"2".add(value: 10) // <== returns 12
"Dog".add(value: 10) // <== returns nil