public void HeadTest()
        {
            const string data = "How now, brown cow?";
            var          list = data.Split().Aggregate(AltBinaryRandomAccessList <string> .Empty, (current, word) => AltBinaryRandomAccessList <string> .Cons(word, current));

            Assert.AreEqual("cow?", AltBinaryRandomAccessList <string> .Head(list));
        }
        public void EmptyHeadTest()
        {
            var list = AltBinaryRandomAccessList <string> .Empty;
            var ex   = AssertThrows <ArgumentException>(() => AltBinaryRandomAccessList <string> .Head(list));

            Assert.AreEqual("must be Zero or One\r\nParameter name: dataType", ex.Message);
        }