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iOS Intermediate Swift 2 Extensions and Protocols Protocol Extensions

task is to provide a default implementation for the method through a protocol extension.

please help me with this :\ In the editor, you've been provided with a protocol, Math, that contains a single requirement - a method that computes the square of a value. Your task is to provide a default implementation for the method through a protocol extension.

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

// Enter your code below

2 Answers

Arthur,

Its asking that you are put the function into the extension. Second, we return value * value

extension Math {
    func square(let value: Double) -> Double {
        return value * value
    }
}
Greg Kaleka
Greg Kaleka
39,019 Points

What's the extra let for?

not work..

Greg Kaleka
Greg Kaleka
39,019 Points

Hey Arthur,

It works fine - you just need to put this below the comment. If you replace the protocol, it won't work. You have to extend it separately!

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

// Enter your code below extension Calculator { func square(_ value: Double) -> Double { return value * value } }