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 // reference_wrapper& operator=(const reference_wrapper<T>& x);
15 
16 #include <functional>
17 #include <cassert>
18 
19 class functor1
20     : public std::unary_function<int, char>
21 {
22 };
23 
24 template <class T>
25 void
26 test(T& t)
27 {
28     std::reference_wrapper<T> r(t);
29     T t2 = t;
30     std::reference_wrapper<T> r2(t2);
31     r2 = r;
32     assert(&r2.get() == &t);
33 }
34 
35 void f() {}
36 void g() {}
37 
38 void
39 test_function()
40 {
41     std::reference_wrapper<void ()> r(f);
42     std::reference_wrapper<void ()> r2(g);
43     r2 = r;
44     assert(&r2.get() == &f);
45 }
46 
47 int main()
48 {
49     void (*fp)() = f;
50     test(fp);
51     test_function();
52     functor1 f1;
53     test(f1);
54     int i = 0;
55     test(i);
56     const int j = 0;
57     test(j);
58 }
59