anchor.diff:  %%%----------------------------------------------------------------------
   
   -define(INFINITY, 1000000).
  --define(undef, undef).
  +-define(ERROR_UNDEF, undef).
   
   %%%----------------------------------------------------------------------
   %%% Records
  
positive.code: 		{NextTemp, RestTemp} = state:trim_head(ReplayState),
  		{NextTemp, RestTemp, {current, []}}
  	end,
      ContextToRun = Context#context{current = Next, error = ?undef},
      #context{active = Active, blocked = Blocked, error = Error,
  	     state = State, details = Det} = RunContext = run(ContextToRun),
      %% Update active and blocked sets, moving Lid from active to blocked,
  
negative.code:                   blocked        :: ?SET_TYPE(lid:lid()),
  		  current        :: lid:lid(),
  		  details        :: boolean(),
                    error          :: ?ERROR_UNDEF | error:error(),
                    state          :: state:state()}).
  
  %% Internal message format
  