How to access the template function that is stored in the structure?

struct taskinfo{
    template <class callable, class... arguments>
    taskinfo(callable&& f, arguments&&... args){
        std::function<typename std::result_of<callable(arguments...)>::type()> task(std::bind(std::forward<callable>(f), std::forward<arguments>(args)...));
    }
};

void test2(int a)
{
    printf("%i\n", a);
    return;
}

int main()
{
    taskinfo t1(&test2,100);
    std::priority_queue<taskinfo> tasks;
    tasks.push(t1);
    //tasks.top(). Execute task
    return 0;
}

I need to execute tasks by popping out of priority queues. My goal is to have a structure with function with any return type and accepting variable arguments.