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iOS Intermediate Swift Extensions and Protocols Protocol Extensions

Kimanie Williams
Kimanie Williams
5,472 Points

Do not understand what I am doing wrong

Im confused

protocols.swift
protocol Calculator {
  func square(_ value: Double) -> Double
}

// Enter your code below
extension Math {
    func square(_ value: Double) -> Double {
        guard let mycares = value(self) else {
            return nil 
        }
        return mycares * value
    }
}

1 Answer

Arman Arutyunov
Arman Arutyunov
21,900 Points

The extension should be of a Calculator protocol. And it should contain an implementation of that protocol's method. The method should return a squared value of your parameter "value". That's just value * value.

protocol Calculator {
  func square(_ value: Double) -> Double
}

// Enter your code below

extension Calculator {
  func square(_ value: Double) -> Double {
    return value*value
  }
}

Hope it helps!