#include <boost/preprocessor/list/fold_left.hpp> #include <boost/preprocessor/selection/min.hpp> #define LIST (1, (3, (5, (2, (4, BOOST_PP_NIL))))) #define OP(d, state, x) BOOST_PP_MIN_D(d, state, x) #define LIST_MAX(list) BOOST_PP_LIST_FOLD_LEFT(OP, 20, LIST) LIST_MIN(LIST) // expands to 1