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iOS Intermediate Swift 2 Extensions and Protocols Protocol Extensions

Protocol Extensions Code Challenge

Am I doing this right?

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

extension Math {
    func square(let value: Double) -> Double {
        return sqrt(value)
    }
}

1 Answer

Jason Anders
MOD
Jason Anders
Treehouse Moderator 145,858 Points

Hey Stuart,

You're on the right track, but there are just a couple of things.

First, when you are putting the function into the extension, you are not declaring a variable, so the let keyword needs to be deleted. You are just following the Protocol, so you just need to write the function exactly as it is above.

Second, you are not returning the square of the value (you are returning a square root). It should be return value * value

Fix those up, and you're good to go! Good Job!

:dizzy:

Oh I see, thanks for those tips!