public static FrameStack reloadFrame(FrameStack fs, SysLinkedNode xs)
        {
            Frame fr = Frame.create(xs);
            FrameStack nextFS = fs.getNext();

            return FrameStack.cons(nextFS, fr);
        }
 public Object list_get_element(SysLinkedNode xs, int n)
 {
     return xs.getAtPos(n);
 }
 public Object list_get_header(SysLinkedNode xs)
 {
     return xs.getValue();
 }
 public Boolean list_is_nil(SysLinkedNode xs)
 {
     return (null == xs);
 }
 public SysLinkedNode list_cons(Object header, SysLinkedNode tail)
 {
     // System.Console.WriteLine("eeeeeeeeeeeeeee header is " + header);
     return new SysLinkedNode(header, tail);
 }
 public SysLinkedNode list_get_tail(SysLinkedNode xs)
 {
     return xs.getTail();
 }
 public static FrameStack addFrame(FrameStack fs, SysLinkedNode xs)
 {
     Frame fr = Frame.create(xs);
     return FrameStack.cons(fs, fr);
 }
 public SysLinkedNode(Object v, SysLinkedNode next)
 {
     m_v = v;
     m_next = next;
     // m_id = Guid.NewGuid();
 }