rem: BOOST_CHECK(add_returned_non_null_value);
add: BOOST_TEST(add_returned_non_null_value);
context: wide_free_functions_tests(){    symbols<int, wchar_t>   sym;    int *res = add(sym,L"pineapple");    BOOST_CHECK(add_returned_non_null_value);    res = add(sym,L"pineapple");    BOOST_CHECK(add_returned_null);    res = find(sym, L"pineapple");    BOOST_CHECK(find_returned_non_null_value);    res = find(sym, L"banana");    BOOST_CHECK(find_returned_null);};