presto-main/src/main/java/io/prestosql/operator/aggregation/minmaxby/BooleanAndBlockPositionStateSerializer.java/BooleanAndBlockPositionStateSerializer/writeFirstField
class BooleanAndBlockPositionStateSerializer:    @Override
    void writeFirstField(BlockBuilder out, BooleanAndBlockPositionValueState state)
    {
        firstType.writeBoolean(out, state.getFirst());
    }