1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
|
// is_function example
#include <iostream>
#include <type_traits>
int a(int i){return i;} // function
int(*b)(int)=a; // pointer to function
struct C { int operator()(int i){return i;} } c; // function-like class
int main() {
std::cout << std::boolalpha;
std::cout << "is_function:" << std::endl;
std::cout << "decltype(a): " << std::is_function<decltype(a)>::value << std::endl;
std::cout << "decltype(b): " << std::is_function<decltype(b)>::value << std::endl;
std::cout << "decltype(c): " << std::is_function<decltype(c)>::value << std::endl;
std::cout << "C: " << std::is_function<C>::value << std::endl;
std::cout << "int(int): " << std::is_function<int(int)>::value << std::endl;
std::cout << "int(*)(int): " << std::is_function<int(*)(int)>::value << std::endl;
return 0;
}
| |