1 //===----------------------------------------------------------------------===//
2 //
3 //                     The LLVM Compiler Infrastructure
4 //
5 // This file is dual licensed under the MIT and the University of Illinois Open
6 // Source Licenses. See LICENSE.TXT for details.
7 //
8 //===----------------------------------------------------------------------===//
9 
10 // <functional>
11 
12 // reference_wrapper
13 
14 // template <ObjectType T> reference_wrapper<T> ref(reference_wrapper<T>t);
15 
16 #include <functional>
17 #include <cassert>
18 
19 #include "counting_predicates.hpp"
20 
is5(int i)21 bool is5 ( int i ) { return i == 5; }
22 
23 template <typename T>
call_pred(T pred)24 bool call_pred ( T pred ) { return pred(5); }
25 
main()26 int main()
27 {
28     {
29     int i = 0;
30     std::reference_wrapper<int> r1 = std::ref(i);
31     std::reference_wrapper<int> r2 = std::ref(r1);
32     assert(&r2.get() == &i);
33     }
34     {
35     unary_counting_predicate<bool(*)(int), int> cp(is5);
36     assert(!cp(6));
37     assert(cp.count() == 1);
38     assert(call_pred(cp));
39     assert(cp.count() == 1);
40     assert(call_pred(std::ref(cp)));
41     assert(cp.count() == 2);
42     }
43 }
44