public void It_second_set_t2()
        {
            var res = CallFresh((q) => Eq(q, 5))(EmptyState);

            Cdr(res).must_be_nil();
        }
        public void It_who_cares()
        {
            var res = Take(1, CallFresh((q) => fives()(q))(EmptyState));

            res.ToString().must_equal("(((([0] . 5)) . 1))");
        }
        public void It_second_set_t1()
        {
            var res = Car(CallFresh((q) => Eq(q, 5))(EmptyState));

            res.ToString().must_equal("((([0] . 5)) . 1)");
        }