1 //===----------------------------------------------------------------------===//
2 //
3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4 // See https://llvm.org/LICENSE.txt for license information.
5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6 //
7 //===----------------------------------------------------------------------===//
8 
9 // <functional>
10 
11 // reference_wrapper
12 
13 // template <ObjectType T> reference_wrapper<T> ref(reference_wrapper<T>t);
14 
15 #include <functional>
16 #include <cassert>
17 
18 #include "counting_predicates.hpp"
19 
20 #include "test_macros.h"
21 
22 bool is5 ( int i ) { return i == 5; }
23 
24 template <typename T>
25 bool call_pred ( T pred ) { return pred(5); }
26 
27 int main(int, char**)
28 {
29     {
30     int i = 0;
31     std::reference_wrapper<int> r1 = std::ref(i);
32     std::reference_wrapper<int> r2 = std::ref(r1);
33     assert(&r2.get() == &i);
34     }
35     {
36     unary_counting_predicate<bool(*)(int), int> cp(is5);
37     assert(!cp(6));
38     assert(cp.count() == 1);
39     assert(call_pred(cp));
40     assert(cp.count() == 1);
41     assert(call_pred(std::ref(cp)));
42     assert(cp.count() == 2);
43     }
44 
45   return 0;
46 }
47