using System;

public class Program

{

    public static void Main()

    {

        var name = "Kyle";

​

        // local function

        string sayHello1()

        {

            return $"Hello, {name}";

        }

​

        // exression-bodied local function

        string sayHello2() => $"Hello, {name}";

​

        // explicit lambda

        Func<string> sayHello3 = () => $"Hello, {name}";

        // func constructor

        var sayHello4 = new Func<string>(() => $"Hello, {name}");

​

        // explicit return type (C#10)

        // Feature 'lambda return type' is not available in C# 9.0.

        var sayHello5 = string () => $"Hello, {name}";

​

        // implicit lambda (C#10)

        // Feature 'inferred delegate type' is not available in C# 9.0.

        var sayHello6 = () => $"Hello, {name}";

​

        Console.WriteLine(sayHello1());

        Console.WriteLine(sayHello2());

        Console.WriteLine(sayHello3());

        Console.WriteLine(sayHello4());

        Console.WriteLine(sayHello5());

        Console.WriteLine(sayHello6());

    }

}