image/svg+xml
boost::mpl::fold<...>
boost_::mpl::vector< boost_::mpl::vector<mpl_::char_<'+'>, mpl_::integral_c<int, 2>>, boost_::mpl::vector<mpl_::char_<'+'>, mpl_::integral_c<int, 3>>, boost_::mpl::vector<mpl_::char_<'+'>, mpl_::integral_c<int, 4>>>
sum_items
mpl_::integral_c<int, 9>
mpl_::integral_c<int, 2>
sum_items
boost::mpl::int_<0>
mpl_::integral_c<int, 5>
sum_items