anchor.diff:      _ = [ begin
               T   = if is_integer(K) -> i; true -> s end,
               Fn  = list_to_atom(lists:concat([Op, "x_state_", T])),
  -            Res = case maps:is_key(K, Map) of true -> {}; false -> error end,
  +            Res = case maps:is_key(K, Map) of true -> {}; false -> OogErr end,
               Res = Call(Fn, Unit, {K, V})
             end || {Map, Delta} <- [{MapI1, DeltaI2}, {MapS1, DeltaS2}],
                  {Op, K, V} <- Delta ],
  
positive.code:     <<"top">>    = ?call(call_contract, Acc1, Stack, pop, string, {}),
      <<"middle">> = ?call(call_contract, Acc1, Stack, pop, string, {}),
      <<"bottom">> = ?call(call_contract, Acc1, Stack, pop, string, {}),
      error        = ?call(call_contract, Acc1, Stack, pop, string, {}),
      ok.
  
  sophia_spend(_Cfg) ->
  
negative.code:         case aect_call:return_type(Call) of
              ok     -> {ok, Res} = aeso_data:from_binary(Type, aect_call:return_value(Call)),
                        Res;
              error  -> {error, aect_call:return_value(Call)};
              revert -> revert
          end,
      {Result, S1}.
  