1 // { dg-do compile { target c++11 } }
2 template<typename T1, typename T2>
3 struct pair {};
4 
5 template<typename... Args>
6 struct tuple {
7   static const int value = 0;
8 };
9 
10 template<>
11 struct tuple<pair<int, float> > {
12   static const int value = 1;
13 };
14 
15 template<typename U>
16 struct tuple<pair<int, U> > {
17   static const int value = 2;
18 };
19 
20 template<typename T, typename U>
21 struct tuple<pair<T, U>, pair<T, U> > {
22   static const int value = 3;
23 };
24 
25 
26 template<typename... Outer>
27 struct X {
28   template<typename... Inner>
29   struct Y
30   {
31     typedef tuple<pair<Outer, Inner>...> type;
32   };
33 };
34 
35 int a0[X<int, double>::Y<short, char>::type::value == 0? 1 : -1];
36 int a1[X<int>::Y<float>::type::value == 1? 1 : -1];
37 int a2[X<int>::Y<double>::type::value == 2? 1 : -1];
38 int a3[X<int, int>::Y<double, double>::type::value == 3? 1 : -1];
39