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Richard Pitts
Courses Plus Student 1,243 PointsNot Sure on this one either!
What is the correct answer?
protocol Calculator {
func square(_ value: Double) -> Double
}
extension Calculator {
func square(_ value: Double) -> Double
}
// Enter your code below
1 Answer
David Papandrew
8,386 PointsHi Richard,
Remember that the protocol just tells you what you need to include but not how. So the protocol will only include the function name and signature (params and return type).
So when you write the extension, you need to write out a fully working function (that also conforms to the protocol).
To do this, you will want to include a return statement inside the body of the function.
Here is the code:
protocol Calculator {
func square(_ value: Double) -> Double
}
// Enter your code below
extension Calculator {
func square(_ value: Double) -> Double {
return value * value
}
}