using System;

using System.Runtime.CompilerServices;

public class Program

{

    public static void Main()

    {

        WhoDoneIt();

        Action x = () => WhoDoneIt();

        x();

        Action y = () => x();

        y();

        ActionFactory()();

        Test(x);

        Test(y);

        Test(ActionFactory());

    }

    private static void Test(Action action) {

        action();   

    }

    private static Action ActionFactory() {

        return () => WhoDoneIt();   

    }

    private static void WhoDoneIt([CallerMemberName] string caller = null) {

        Console.WriteLine(caller);  

    }

}