SPROUT_CXX14_CONSTEXPR reverse_iterator rbegin() SPROUT_NOEXCEPT;
SPROUT_CONSTEXPR const_reverse_iterator rbegin() const SPROUT_NOEXCEPT;
#include <sprout/string.hpp>
using namespace sprout;
SPROUT_STATIC_CONSTEXPR auto input = string<8>("homuhomu");
static_assert(*input.rbegin() == 'u', "input first element of reverse iteration is u.");