#include <iostream>
#include <boost/function.hpp>

struct Functor {

    Functor(void)

        { std::cout << "Functor constructor (" << this << ')' << std::endl; }

    Functor(const Functor&)

        { std::cout << "Functor copy constructor (" << this << ')' << std::endl; }

    ~Functor(void)

        { std::cout << "Functor destructor (" << this << ')' << std::endl; }

    void operator()(void) const

        { std::cout << "Hello world!" << std::endl; }

    std::string memfunc(void) const

        { return std::string("hello world!!!!!!"); }

};

int main(void) 
{
    Functor func; 
    boost::function0<void> f(func);

    return 0;
}