Typed Where

//http://stackoverflow.com/questions/19807573/why-a-lot-of-linq-methods-return-ienumerable-instead-of-a-more-specific-type/19809155#19809155
using System;
using System.Collections.Generic;
using System.Linq;

namespace TypedWhereExample
{
    class Program
    {
        static void Main(string[] args)
        {
            var data = Enumerable.Range(0, 1000);
            var typedWhere1 = data.TypedWhere(x => x % 2 == 0);
            var typedWhere2 = typedWhere1.TypedWhere(x => x % 3 == 0);
            var result = typedWhere2.Take(10).ToList();  //Works like usual Linq

            //But returns additional data
            Console.WriteLine("Result: " + string.Join(",", result));
            Console.WriteLine("Typed Where 1 Skipped: " + typedWhere1.Skipped);
            Console.WriteLine("Typed Where 1 Returned: " + typedWhere1.Returned);
            Console.WriteLine("Typed Where 2 Skipped: " + typedWhere2.Skipped);
            Console.WriteLine("Typed Where 2 Returned: " + typedWhere2.Returned);
            Console.ReadLine();

            //Result: 0,6,12,18,24,30,36,42,48,54
            //Typed Where 1 Skipped: 27
            //Typed Where 1 Returned: 28
            //Typed Where 2 Skipped: 18
            //Typed Where 2 Returned: 10
        }
    }

    public static class MyLINQ
    {
        public static TypedWhereEnumerable<T> TypedWhere<T>
            (this IEnumerable<T> source, Func<T, bool> filter)
        {
            return new TypedWhereEnumerable<T>(source, filter);
        }
    }

    public class TypedWhereEnumerable<T> : IEnumerable<T>
    {
        IEnumerable<T> source;
        Func<T, bool> filter;

        public int Skipped { get; private set; }
        public int Returned { get; private set; }

        public TypedWhereEnumerable(IEnumerable<T> source, Func<T, bool> filter)
        {
            this.source = source;
            this.filter = filter;
        }

        IEnumerator<T> IEnumerable<T>.GetEnumerator()
        {
            foreach (var o in source)
                if (filter(o)) { Returned++; yield return o; }
                else Skipped++;
        }

        System.Collections.IEnumerator System.Collections.IEnumerable.GetEnumerator()
        {
            foreach (var o in source)
                if (filter(o)) { Returned++; yield return o; }
                else Skipped++;
        }
    }
}