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 // class function<R(ArgTypes...)>
12 
13 // template<typename T>
14 //   requires Callable<T, ArgTypes...> && Convertible<Callable<T, ArgTypes...>::result_type, R>
15 //   T*
16 //   target();
17 // template<typename T>
18 //   requires Callable<T, ArgTypes...> && Convertible<Callable<T, ArgTypes...>::result_type, R>
19 //   const T*
20 //   target() const;
21 
22 // This test runs in C++03, but we have deprecated using std::function in C++03.
23 // ADDITIONAL_COMPILE_FLAGS: -D_LIBCPP_DISABLE_DEPRECATION_WARNINGS -D_LIBCPP_ENABLE_CXX03_FUNCTION
24 
25 // UNSUPPORTED: no-rtti
26 
27 #include <functional>
28 #include <new>
29 #include <cstdlib>
30 #include <cassert>
31 
32 #include "test_macros.h"
33 
34 class A
35 {
36     int data_[10];
37 public:
38     static int count;
39 
40     A()
41     {
42         ++count;
43         for (int i = 0; i < 10; ++i)
44             data_[i] = i;
45     }
46 
47     A(const A&) {++count;}
48 
49     ~A() {--count;}
50 
51     int operator()(int i) const
52     {
53         for (int j = 0; j < 10; ++j)
54             i += data_[j];
55         return i;
56     }
57 
58     int foo(int) const {return 1;}
59 };
60 
61 int A::count = 0;
62 
63 int g(int) {return 0;}
64 
65 int main(int, char**)
66 {
67     {
68     std::function<int(int)> f = A();
69     assert(A::count == 1);
70     assert(f.target<A>());
71     assert(f.target<int(*)(int)>() == 0);
72     assert(f.target<int>() == nullptr);
73     }
74     assert(A::count == 0);
75     {
76     std::function<int(int)> f = g;
77     assert(A::count == 0);
78     assert(f.target<int(*)(int)>());
79     assert(f.target<A>() == 0);
80     assert(f.target<int>() == nullptr);
81     }
82     assert(A::count == 0);
83     {
84     const std::function<int(int)> f = A();
85     assert(A::count == 1);
86     assert(f.target<A>());
87     assert(f.target<int(*)(int)>() == 0);
88     assert(f.target<int>() == nullptr);
89     }
90     assert(A::count == 0);
91     {
92     const std::function<int(int)> f = g;
93     assert(A::count == 0);
94     assert(f.target<int(*)(int)>());
95     assert(f.target<A>() == 0);
96     assert(f.target<int>() == nullptr);
97     }
98     assert(A::count == 0);
99 
100   return 0;
101 }
102