Hello, I try to use parts of boost.test lib not for unit testing self but inside an algorithm. Anyway, at the end of header http://www.boost.org/doc/libs/1_53_0/boost/test/floating_point_comparison.hp... this is written inside anonymous namespace it works obviously, but not at me. What happened here and how to fix it? Did I not read the header carefully? Thanks, Olaf ---8<---- #include <boost/test/floating_point_comparison.hpp> namespace tools { using boost::test_tools::check_is_small_t; check_is_small_t const& check_is_small = unit_test::ut_detail::static_constant<check_is_small_t>::value; } int main() { bool ok = tools::check_is_small(900, 0.1); } --->8---- test.cpp:5:30: error: 'boost::test_tools::check_is_small_t' has not been declared test.cpp:7:5: error: 'check_is_small_t' does not name a type test.cpp: In function 'int main()': test.cpp:12:15: error: 'check_is_small' is not a member of 'tools'