220   struct C : B {};  struct
520   template<typename T, unsigned N> struct array {  struct
521     constexpr array() : arr{} {}  in array()  function
523     constexpr array(X ...x) : arr{} {  in array()  function
526     template<int ...I, typename ...X> constexpr void init(ints<I...>, X ...x) {  in init()
529     T arr[N];
530     struct iterator {
537     constexpr iterator begin() { return iterator(arr); }  in begin()
538     constexpr iterator end() { return iterator(arr + N); }  in end()
582   struct C : B {  struct
583     B b;
584     int n = 5;