- friend class RulerTest::tick_position_test_0;
- friend class RulerTest::tick_position_test_1;
- friend class RulerTest::tick_position_test_2;
+ friend struct RulerTest::tick_position_test_0;
+ friend struct RulerTest::tick_position_test_1;
+ friend struct RulerTest::tick_position_test_2;