#include <functional>
#include <iostream>
typedef void (*VF)();
VF Test() {
return nullptr;
}
int main(int argc, char* argv[]) {
std::function<void()> foo;
std::cout << !!foo << std::endl;
foo = nullptr;
std::cout << !!foo << std::endl;
foo = Test();
std::cout << !!foo << std::endl;
return 0;
}
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