ConsList.cs

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

namespace ConsoleApplication1
{
    class ConsList<T> : IEnumerable where T : IComparable<T>
    {
        private const string EXCEPTION = "Cannot traverse empty list";
        private T _head;
        private ConsList<T> _tail;

        public ConsList(T head, ConsList<T> tail)
        {
            IsEmpty = false;
            Head = head;
            Tail = tail;
        }

        public static ConsList<T> Init(params T[] items)
        {
            var count = items.Length - 1;
            var list = Nil;

            for (var i = count; i >= 0; i--)
            {
                list = list.Prepend(items[i]);
            }

            return list;
        }

        public bool IsEmpty { get; protected set; }

        public static ConsList<T> Nil
        {
            get
            {
                return new ConsList<T>(default(T), null) { IsEmpty = true };
            }
        }

        public T Head
        {
            get
            {
                if (!IsEmpty) return _head;
                else throw new NullReferenceException("Head of empty list");
            }
            protected set
            {
                _head = value;
            }
        }

        public ConsList<T> Tail
        {
            get
            {
                if (!IsEmpty) return _tail;
                else throw new NullReferenceException("Tail of empty list");
            }
            protected set
            {
                _tail = value;
            }
        }

        public ConsList<T> Prepend(T value)
        {
            return new ConsList<T>(value, this);
        }

        public ConsList<T> Reverse()
        {
            var result = Nil;
            ForEach(h => result = result.Prepend(h));
            return result;
        }

        public IEnumerator GetEnumerator()
        {
            var temp = this;
            while (temp.IsEmpty == false)
            {
                yield return temp.Head;
                temp = temp.Tail;
            }
        }

        public void ForEach(Action<T> headAction)
        {
            var temp = this;
            while (temp.IsEmpty == false)
            {
                headAction(temp.Head);
                temp = temp.Tail;
            }
        }

        public List<T> ToList()
        {
            var lst = new List<T>();
            ForEach(h => lst.Add(h));
            return lst;
        }
    }
}