namespace Test
{
public static class MyExtensions
{
    public static IEnumerable<T> Where<T> (this IEnumerable<T> source, Func<T, bool> predicate)
    {
        foreach(var item in source)
        {
            if(predicate(item))
            {

public static PerpetualEnumerator<T> GetPerpetualEnumerator<T>(this IEnumerable<T> items)
{
    return new PerpetualEnumerator<T>(items);
}

using System.Collections;
using System.Collections.Generic;
 
namespace nl4net
{
    /// <summary>
    /// Wraps a standard IEnumerator&lt;T&gt; to provide
    /// iteration over a generic collection that automatically 
    /// resets to the beginning once it reaches the end.
    /// </summary>

using System;
using System.Linq;
 
namespace ConsoleApplication1
{
    class Program
    {
        static void Main(string[] args)
        {
            Person[] people = new Person[] {