anchor.diff:              NewEntryAndResult(Entry, Value);
           {fail, not_a_number} ->
               NewEntryAndResult(Entry, Value);
  -        {fail, Reason} ->
  -            {Entry, {fail, Reason}};
  +        {fail, _Reason} = Failed ->
  +            {Entry, Failed};
           value ->
               NewEntryAndResult(Entry, Value);
           not_found ->
  
positive.code:             E2 = tx_tlog:set_entry_value(E1, Value),
              E3 = tx_tlog:set_entry_status(E2, value),
              {E3, {ok}}
      end.
  
  %% @doc Simulate a change on a set via read and write requests.
  
negative.code:             tlog_write(Entry, Key, X);
          {ok, _} ->
              Error = {fail, not_a_number},
              {update_tlog_entry_2phase_op(Entry, Error), Error};
          E when erlang:is_tuple(E) -> %% other previous error
              {Entry, E}
      end.
  