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iOS Intermediate Swift Extensions and Protocols Protocol Extensions

Kristof Kocsis
Kristof Kocsis
15,455 Points

Method isn't recognised on an instance of the class

I copied the code from tohe video to my xcode project:

protocol RandomNumberGenerator {
    func random() -> Int

extension RandomNumberGenerator {
    func random() -> Int {
        return Int(arc4random())

class Generator: RandomNumberGenerator {}

let generator = Generator.random()

however on the last line, I got an error: "Use of instance member 'random' on type 'Self'; did you mean to use a value of type 'Self' instead?"

What does this mean? Did the code depracate, or am I missing something?

1 Answer

Dhanish Gajjar
Dhanish Gajjar
20,185 Points

The correct syntax is

let generator = Generator().random()

You create in instance of Generator by

let generator = Generator()

and then you call the function with .random()

Hope it helps.

Kristof Kocsis
Kristof Kocsis
15,455 Points

Well this was a stupid question but thank you for the help.