Welcome to the Treehouse Community

The Treehouse Community is a meeting place for developers, designers, and programmers of all backgrounds and skill levels to get support. Collaborate here on code errors or bugs that you need feedback on, or asking for an extra set of eyes on your latest project. Join thousands of Treehouse students and alumni in the community today. (Note: Only Treehouse students can comment or ask questions, but non-students are welcome to browse our conversations.)

Looking to learn something new?

Treehouse offers a seven day free trial for new students. Get access to thousands of hours of content and a supportive community. Start your free trial today.

iOS Intermediate Swift 2 Extensions and Protocols Protocol Extensions

Habib Miranda
Habib Miranda
7,320 Points

Can someone help me on this?

I've tried a few things and can't figure it out. Sorry my code isn't in here!

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

// Enter your code below

1 Answer

Steven Deutsch
Steven Deutsch
21,046 Points

Hey Habib Miranda,

So we were given a protocol, Math, which contains a single method. This method is called square, takes a single argument of type Double, and returns a Double value.

The challenge wants us to use an extension on this protocol to create a default implementation for this method. We have to follow the conventions we set in the original protocol, meaning, this method has to have the same name and function signature.

In the body of the function, we will compute the square value of the value we pass in when calling this method.

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

// Enter your code below

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

Good Luck