well, I wrote a timer with a callback function func

struct Timer 
{
    std::function<void(int)> func;   //---- sockfd
    //...
    Timer(int fd) : clientFd(fd)
    {
        //...
    }
};

has a time wheel

class TimeWheel 
{
private:
    std::array<std::list<Timer*>, N> slots; // N , Si
    //...
 
public:
    //...
     void tick();
};

tick function of the time wheel

void TimeWheel::tick() 
{
    auto it = slots[currentSlot].begin();
    //...
            (*it)->func((*it)->clientFd);  //
            slots[currentSlot].erase(it);
 //...
}

then there is a time wheel variable timeWheel, in epoll that encapsulates a timer every time there is a new connection, adds you to the corresponding slot of the time wheel, and executes tick

void Epoll::shutDownFd(int fd) 
{
    // int op = EPOLL_CTL_DEL;
    // epoll_Ctl(fd, op);
    close(fd);
}

void Epoll::addToTimeWheel(int fd) // fd 
{
    Timer* timer = new Timer(fd);
    timer->func = bind(&Epoll::shutDownFd, *this, placeholders::_1);
    timeWheel.addTimer(timer);
}


// timerfd_create  epoll 
if (events[i].data.fd == timerFd) 
{
   timeWheel.tick();   //
}

but now the gPP compiler reports an error, and several pages of error messages are mainly:

 no matching function for call to  "std::tuple<Epoll, std::_Placeholder<1> >::tuple(Epoll&, const std::_Placeholder<1>&)" 
  : _M_f(std::move(__f)), _M_bound_args(std::forward<_Args>(__args)...)
             
/usr/include/cPP/7/tuple:981:16: error: no type named  "type"  in  "struct std::enable_if<false, bool>" 
  bool>::type = false>


/usr/include/cPP/7/tuple:970:16: error: no type named  "type"  in  "struct std::enable_if<false, bool>" 
  bool>::type = true>
          
                                                         ^
/usr/include/cPP/7/tuple:955:16: error: no type named  "type"  in  "struct std::enable_if<false, bool>" 
  bool>::type = false>
   

this kind of thing, after checking for a day, I still don"t have a clue. I can"t thank you enough to kneel down and ask the boss for advice.