#include <iostream> #include <boost/preprocessor/stringize.hpp> #include <boost/preprocessor/iterate.hpp> #define X() 4 #define BOOST_PP_VALUE 1 + 2 + 3 + X() ??=include BOOST_PP_ASSIGN_SLOT(1) #undef X int main(void) { std::cout << BOOST_PP_STRINGIZE(BOOST_PP_SLOT(1)) // outputs "10" << &std::endl; return 0; }