1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
|
//===----------------------------------------------------------------------===//
//
// The LLVM Compiler Infrastructure
//
// This file is dual licensed under the MIT and the University of Illinois Open
// Source Licenses. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
// <functional>
// class function<R(ArgTypes...)>
// template<typename T>
// requires Callable<T, ArgTypes...> && Convertible<Callable<T, ArgTypes...>::result_type, R>
// T*
// target();
// template<typename T>
// requires Callable<T, ArgTypes...> && Convertible<Callable<T, ArgTypes...>::result_type, R>
// const T*
// target() const;
#include <functional>
#include <new>
#include <cstdlib>
#include <cassert>
class A
{
int data_[10];
public:
static int count;
A()
{
++count;
for (int i = 0; i < 10; ++i)
data_[i] = i;
}
A(const A&) {++count;}
~A() {--count;}
int operator()(int i) const
{
for (int j = 0; j < 10; ++j)
i += data_[j];
return i;
}
int foo(int) const {return 1;}
};
int A::count = 0;
int g(int) {return 0;}
int main()
{
{
std::function<int(int)> f = A();
assert(A::count == 1);
assert(f.target<A>());
assert(f.target<int(*)(int)>() == 0);
assert(f.target<int>() == nullptr);
}
assert(A::count == 0);
{
std::function<int(int)> f = g;
assert(A::count == 0);
assert(f.target<int(*)(int)>());
assert(f.target<A>() == 0);
assert(f.target<int>() == nullptr);
}
assert(A::count == 0);
{
const std::function<int(int)> f = A();
assert(A::count == 1);
assert(f.target<A>());
assert(f.target<int(*)(int)>() == 0);
assert(f.target<int>() == nullptr);
}
assert(A::count == 0);
{
const std::function<int(int)> f = g;
assert(A::count == 0);
assert(f.target<int(*)(int)>());
assert(f.target<A>() == 0);
assert(f.target<int>() == nullptr);
}
assert(A::count == 0);
}
|
