Hello, * Problem description The constants do not work with the C++23 FP types. * general hint To prevent (more) warnings it is useful to introduce this macro: #if defined(__STDCPP_FLOAT128_T__) #define BOOST_FLOATMAX_SUFFIX F128 #elif defined(BOOST_CSTDFLOAT_FLOAT128_NATIVE_TYPE) #define BOOST_FLOATMAX_SUFFIX Q #else #define BOOST_FLOATMAX_SUFFIX L #endif * question In constants the namespaces float/double/long_double_constant+detail are created type dependent (in case the value constexpr can be requested). If the value cannot be requested constexpr the conversion is finally done by boost::lexical_cast. But the implementation is very complex. I have a better one - but I may have missed things. If so - which would they be? * My solution (BOOST_MAKE_MATH_CONSTANT) see constants_more.hpp, advantages: - works with all FP types - compatible to the existing implementation CONSTANT<Type>() - is clear/understandable (comments) - may need only one additional namespace static_constants (and not 4) - provides the constants additionally as CONSTANT_v (constexpr) or static_constants::CONSTANT_v (not constexpr) (if possible) What is your opinion? Are there still errors in it? It would be even nicer if boost::lexical_cast and/or boost::math::tools::convert_from_string were constexpr. This would further simplify the implementation. thx + regards Gero