anchor.diff:  -type rtm() :: {?RT:key(),
                   comm:mypid() | unknown,
                   Role :: non_neg_integer(),
  -                Acceptor :: comm:mypid() | unknown}.
  +                (Acceptor :: comm:mypid()) | unknown}.
   
   -type rtms() :: [rtm()].
   
  
positive.code:                                 learner:start_paxosid(GLLearner, PaxId, Maj,
                                                        comm:this(), ItemId),
                                  %% add learner to running paxos acceptors
                                  _ = [ case unknown =/= X of
                                            true -> comm:send(X,
                                                              {acceptor_add_learner,
                                                               PaxId, GLLearner});
                                            false -> ok
                                        end || X <- Accs],
                                  Proposer =
                                      comm:make_global(get_my(Role, proposer)),
                                  proposer:start_paxosid(
                                    Proposer, PaxId, _Acceptors = Accs, abort,
                                    Maj, length(Accs) + 1, ThisRTMsNumber),
                                  ok
                              end
                              || {PaxId, _RTLog, _TP}
  
negative.code:     Tid = tx_state:get_tid(TxState),
      RTMs = tx_state:get_rtms(TxState),
      CleanRTMs = rtms_get_rtmpids(RTMs),
      Accs = [ X || X <- rtms_get_accpids(RTMs), unknown =/= X ],
      TM = comm:this(),
      _ = [ begin
            %% ItemState = lists:keyfind(ItemId, 1, ItemStates),
  