: public _Tuple_impl<_Idx + 1, _Tail...>,
private _Head_base<_Idx, _Head>
{
- template<size_t, typename...> friend class _Tuple_impl;
+ template<size_t, typename...> friend struct _Tuple_impl;
typedef _Tuple_impl<_Idx + 1, _Tail...> _Inherited;
typedef _Head_base<_Idx, _Head> _Base;
struct _Tuple_impl<_Idx, _Head>
: private _Head_base<_Idx, _Head>
{
- template<size_t, typename...> friend class _Tuple_impl;
+ template<size_t, typename...> friend struct _Tuple_impl;
typedef _Head_base<_Idx, _Head> _Base;