1 // { dg-do compile { target c++11 } }
2
3 typedef decltype(sizeof(char)) size_type;
4
5 template<class T, size_type N, class Pred>
6 constexpr size_type do_find_if_or_stop(T (&x)[N], size_type i, Pred p);
7
8 template<class T, size_type N, class Pred>
do_find_if(T (& x)[N],size_type i,Pred p)9 constexpr size_type do_find_if(T (&x)[N], size_type i, Pred p) {
10 return p(x[i]) ? i : do_find_if_or_stop(x, i + 1, p); // line 8
11 }
12
13 template<class T, size_type N, class Pred>
do_find_if_or_stop(T (& x)[N],size_type i,Pred p)14 constexpr size_type do_find_if_or_stop(T (&x)[N], size_type i, Pred p) {
15 return i == N ? N : do_find_if(x, i, p);
16 } // Line 14
17
18 template<class T, size_type N, class Pred>
find_if(T (& x)[N],Pred p)19 constexpr size_type find_if(T (&x)[N], Pred p) {
20 return do_find_if(x, 0, p); // Line 18
21 }
22
23 constexpr long items_long[] = {1, 2, 3, 4, -5, 6, -7, 8};
24
25 template<class T>
26 struct IsNegative {
operatorIsNegative27 constexpr bool operator()(const T& x) {
28 return x < T(0);
29 }
30 };
31
32 constexpr auto pos1 = find_if(items_long, IsNegative<long>{}); // Line 30
33
34 static_assert(pos1 == 4, "find_if failure");
35