java heterogenous lists madness

HList.java

public abstract class HList {

    public abstract int length();

    public static H0 of() {
        return Nil;
    }

    public static <T1> H1<T1> of(T1 v1) {
        return new H1<T1>(v1);
    }

    public static <T1, T2> H2<T1, T2> of(T1 v1, T2 v2) {
        return new H2<T1, T2>(v1, v2);
    }

    public static <T1, T2, T3> H3<T1, T2, T3> of(T1 v1, T2 v2, T3 v3) {
        return new H3<T1, T2, T3>(v1, v2, v3);
    }

    public static <T1, T2, T3, T4> H4<T1, T2, T3, T4> of(T1 v1, T2 v2, T3 v3, T4 v4) {
        return new H4<T1, T2, T3, T4>(v1, v2, v3, v4);
    }

    public static <T1, T2, T3, T4, T5> H5<T1, T2, T3, T4, T5> of(T1 v1, T2 v2, T3 v3, T4 v4, T5 v5) {
        return new H5<T1, T2, T3, T4, T5>(v1, v2, v3, v4, v5);
    }

    public static class H0 extends HList {
        @Override
        public int length() {
            return 0;
        }
    }

    public static H0 H0 = new H0();

    public static class H1<T1> extends Cons<T1, H0> {
        public H1(T1 v1) {
            super(v1, H0);
        }
    }

    public static class H2<T1, T2> extends Cons<T1, H1<T2>> {
        public H2(T1 v1, T2 v2) {
            super(v1, new H1<T2>(v2));
        }
    }

    public static class H3<T1, T2, T3> extends Cons<T1, H2<T2, T3>> {
        public H3(T1 v1, T2 v2, T3 v3) {
            super(v1, new H2<T2, T3>(v2, v3));
        }
    }

    public static class H4<T1, T2, T3, T4> extends Cons<T1, H3<T2, T3, T4>> {
        public H4(T1 v1, T2 v2, T3 v3, T4 v4) {
            super(v1, new H3<T2, T3, T4>(v2, v3, v4));
        }
    }

    public static class H5<T1, T2, T3, T4, T5> extends Cons<T1, H4<T2, T3, T4, T5>> {
        public H5(T1 v1, T2 v2, T3 v3, T4 v4, T5 v5) {
            super(v1, new H4<T2, T3, T4, T5>(v2, v3, v4, v5));
        }
    }

    private static class Cons<H, T extends HList> extends HList {

        private final H head;
        private final T tail;

        public Cons(H head, T tail) {
            this.head = head;
            this.tail = tail;
        }

        public H head() {
            return head;
        }

        public T tail() {
            return tail;
        }

        @Override
        public int length() {
            return 1 + this.tail.length();
        }

        public static <H, T extends HList> Cons<H, T> of(H h, T v) {
            return new Cons<H, T>(h, v);
        }

    }

}

PlayingAround.java

public class PlayingAround {
    
    static {

        HList.of(new StringBuilder(), 3, "mystring").head().append("ab");

        HList.of(new StringBuilder(), 3, "mystring").length();

        HList.of("abc", "cde").tail().tail().length();

        HList.H2<Integer, String> l = HList.of(new StringBuilder(), 3, "mystring").tail();

    }
    

}