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iOS Intermediate Swift Extensions and Protocols Protocol Extensions

Posted by Neil Zimmerman
Neil Zimmerman
4,388 Points

Why do we want to restate the function of square in the extension?

I don't understand how this changes default implementation. Is the default implementation suppose to be the function square and are we replacing it with a new function and if so how do we know what to put in it? I saw in another question for this that they put a let in the parameter I am trying to find where it explains that we can do that. I thought parameters is used to have something explained what value you need to put in not to have a constant or variable run inside it. I am also really confused on why we do anything at this point.

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

// Enter your code below
extension Calculator {
    return value * value
}

1 Answer

tromben98
tromben98
13,273 Points
tromben98
tromben98
13,273 Points 
protocol Calculator {
  func square(_ value: Double) -> Double
}

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