package Bucket;
      has '_linkedlist' => (
               traits    =>  ['LinkedList'], 
               is        => 'rw', 
               isa       => 'LinkedListRef[Any]', 
               handles   => {
                  _add_link  => 'append',
                  _insert_link   => 'insert',
                  _count_links => 'size',
                  _del_link => 'remove',
                  _split_at_link => 'split',
                  _has_sublinks => 'has_children', 
               }
       };