anchor.diff:          {_, NewState} ->
               [PRateFun, PTimeFun | Tail] = Rates,
               LocalStart = msnow(),
  -            looprun(N, PTimeFun, Iterator, Spawn, {constant, PRateFun}, Body, WorkerProvider, NewState, Env),
  +            looprun(N, PTimeFun, Iterator, Spawn, #const_rate{rate_fun = PRateFun}, Body, WorkerProvider, NewState, Env),
               LoopTime = msnow() - LocalStart,
               NewTimeFun =
                   fun (S) ->
  
positive.code:             {nil, State3};
          false ->
              RPSFun = fun (S) -> {undefined, S} end,
              looprun(ProcNum, TimeFun, Iterator, Spawn, {constant, RPSFun}, Body, WorkerProvider, State3, Env);
          #operation{args = [#constant{value = _, units = _} = RPS]} ->
              RPSFun = Evaluator(RPS),
              looprun(ProcNum, TimeFun, Iterator, Spawn, {constant, RPSFun}, Body, WorkerProvider, State3, Env);
          #operation{args = [#operation{name = think_time,
                                        args = [#constant{units = _} = Rate,
                                                #constant{units = _} = ThinkTime]}]} ->
  
negative.code:                                         #constant{value = _, units = _} = From,
                                          #constant{value = _, units = _} = To]}]} ->
              if
                  From == To -> looprun(ProcNum, TimeFun, Iterator, Spawn, #const_rate{rate_fun = Evaluator(From)}, Body, WorkerProvider, State3, Env);
                  true -> looprun(ProcNum, TimeFun, Iterator, Spawn, #linear_rate{from_fun = Evaluator(From), to_fun = Evaluator(To)}, Body, WorkerProvider, State3, Env)
              end
      end.
  
  