27 constexpr int64_t check_subseconds(Duration d)  in check_subseconds()  function
39     static_assert( check_subseconds(std::chrono::seconds( 1)) == 0, "");  in main()
40     static_assert( check_subseconds(std::chrono::seconds(-1)) == 0, "");  in main()
42     assert( check_subseconds(std::chrono::seconds( 5000)) == 0);  in main()
43     assert( check_subseconds(std::chrono::seconds(-5000)) == 0);  in main()
44     assert( check_subseconds(std::chrono::minutes( 5000)) == 0);  in main()
45     assert( check_subseconds(std::chrono::minutes(-5000)) == 0);  in main()
46     assert( check_subseconds(std::chrono::hours( 11))     == 0);  in main()
47     assert( check_subseconds(std::chrono::hours(-11))     == 0);  in main()
49     assert( check_subseconds(std::chrono::milliseconds( 123456789LL)) == 789);  in main()
50     assert( check_subseconds(std::chrono::milliseconds(-123456789LL)) == 789);  in main()
51     assert( check_subseconds(std::chrono::microseconds( 123456789LL)) == 456789LL);  in main()
52     assert( check_subseconds(std::chrono::microseconds(-123456789LL)) == 456789LL);  in main()
53     assert( check_subseconds(std::chrono::nanoseconds( 123456789LL))  == 123456789LL);  in main()
54     assert( check_subseconds(std::chrono::nanoseconds(-123456789LL))  == 123456789LL);  in main()
56     assert( check_subseconds(microfortnights(  1000)) == 6000);  in main()
57     assert( check_subseconds(microfortnights( -1000)) == 6000);  in main()
58     assert( check_subseconds(microfortnights( 10000)) == 0);  in main()
59     assert( check_subseconds(microfortnights(-10000)) == 0);  in main()