integral_constant
// In header: <boost/parser/tuple.hpp> template<typename T, T I> using integral_constant = hana::integral_constant< T, I >;
A template alias that is boost::hana::integral_constant<T, I> if BOOST_PARSER_USE_HANA_TUPLE is defined, and std::integral_constant<T, I> otherwise.
boost::hana::integral_constant<T, I>
BOOST_PARSER_USE_HANA_TUPLE
std::integral_constant<T, I>
