public bool CasItem(T comparand, T item)
 {
     return(CAS.TryCompareSet(ref _item, item, comparand));
 }
 private void CasTail(Node <T> comparand, Node <T> node)
 {
     CAS.TryCompareSet(ref _tail, node, comparand);
 }
 public bool CasNext(Node <T> comparand, Node <T> node)
 {
     return(CAS.TryCompareSet(ref _next, node, comparand));
 }
 private bool CasHead(Node <T> comparand, Node <T> node)
 {
     return(CAS.TryCompareSet(ref _head, node, comparand));
 }