using System;

using System.Collections.Generic;

​

namespace TestSwitch

{

    class Program

    {

        static void AppendValueToConstList(in List<int> v)

        {

            v.Add(10);

        }

​

        static void Main(string[] args)

        {

            List<int> val = new();

            Console.WriteLine("Before Call");

            foreach (var num in val)

            {

                Console.WriteLine("Got {0}", num);

            }

​

            AppendValueToConstList(val);

            Console.WriteLine("After Call");

            foreach (var num in val)

            {

                Console.WriteLine("Got {0}", num);

            }

        }

    }

}