#include <iostream>
 
int function (int arg) { return arg; }
typedef int (*function_t) (int arg);
 
template <typename T> 
class caller {};
 
template <typename T_ret, typename... T_args> 
class caller<T_ret(*)(T_args...)> {
    T_ret (*m_p) (T_args... args);
public:
    T_ret call (T_args... args) {
        return m_p(args...);
    }
    caller (T_ret (*p)(T_args...args)) : m_p(p) {}
};
 
int main()
{
    caller<decltype(&function)> c(&function);
    std::cout << c.call(1) << std::endl;
    return 0;
}
 

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