try retry in c# in functional

tryRetryFunc.cs

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;

namespace FaultTolerance
{
    class Program
    {
        static void Main(string[] args)
        {
            var start = 2;
            Console.WriteLine(Retry<int>(5, 
                () => Do(start, 1), 
                () => Do(start, 2), 
                () => Do(start, 3), 
                () => Do2(start)).Value);
            Console.ReadKey();
        }

        public static Either<int> Do(int a, int version)
        {
            Console.WriteLine("Do with version " + version);
            return Either<int>.Error;
        }

        public static Either<int> Do2(int a)
        {
            Console.WriteLine("Do2");
            return new Either<int>(a);
        }


        public static Either<T> Retry<T>(int times, params Func<Either<T>>[] fns)
        {
            Console.WriteLine("attempts to remain " + times);
            var fn = fns[times % fns.Length];
            if (times > 1)
            {
                var res = fn();
                if (res.HasError) return Retry(times - 1, fns);
                else return res;
            }
            return fn();
        }
    }

    public class Either<T>
    {
        public static readonly Either<T> Error = new Either<T>();
        public bool HasError { get; private set; }
        public T Value { get; private set; }
        public Either()
        {
            HasError = true;
        }

        public Either(T value)
        {
            Value = value;
        }
    }

}