using System;

using System.Collections.Generic;

​

public class Program {

    private static IEnumerable<IWrapper2> GetSomeNumbers() {

        yield return new Wrapper2 { Value = 1 };

        yield return new Wrapper2 { Value = 2 };

    }

​

    private static void UseSomeNumbers() {

        foreach (var i in GetSomeNumbers()) {

            Console.WriteLine("Got number " + i.Value);

        }

    }

​

    public static void Main() {

        UseSomeNumbers();

    }

    private interface IWrapper {

        int Value { get; }

    }

    private class Wrapper : IWrapper {

        public int Value { get; set; }

    }

    private interface IWrapper2 {

        int Value2 { get; }

    }

    private class Wrapper2 : IWrapper2 {

        public int Value2 { get; set; }

    }

}