anchor.diff:      exchange_tick_period :: non_neg_integer()
   
   }).
  +
  +-type nodeset()         :: ordsets:ordset(node()).
   
   -type state()           :: #state{}.
   
  
positive.code: 
      %% Set of all known members. Used to determine
      %% which members have joined and left during a membership update
      all_members   :: ordsets:ordset(node()) | undefined,
  
      %% Lazy tick period in milliseconds. On every tick all outstanding
      %% lazy pushes are sent out
  
negative.code:     %% Initially trees rooted at each node are the same.
      %% Portions of that tree belonging to this node are
      %% shared in this set.
      common_eagers :: nodeset() | undefined,
  
      %% Initially trees rooted at each node share the same lazy links.
      %% Typically this set will contain a single element. However, it may
      %% contain more in large clusters and may be empty for clusters with
      %% less than three nodes.
      common_lazys  :: nodeset() | undefined,
  
      %% A mapping of sender node (root of each broadcast tree)
      %% to this node's portion of the tree. Elements are
  