// Copyright (c) 2018-2021 Antony Polukhin // // Distributed under the Boost Software License, Version 1.0. (See accompanying // file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt) #include class test_with_protected { protected: int i; char c; public: double d; float f; }; int main() { #ifndef __cpp_lib_is_aggregate // TODO: No known way to detect protected fields # error No known way to detect protected fields. #endif return boost::pfr::tuple_size::value; }