Swift Protocol Delegate Pattern

protocolDelegate.swift

// protocol declaration
protocol myDelegate {
    func myFunction()
}

// Receiver / Performer / Intern
class Receiver: SomeClass, myDelegate {
    
    // instantiate instance of sender class before this
    caller.delegateInstance = self
    
    func myFunction(){
        print("Does something")
    }    
}

// Caller / Sender / Boss
class Caller: OtherClass {
    
    var delegateInstance: myDelegate!
    
    delegateInstance.myFunction()
    
}