c++ - How to use Boost.Signals2 connect_extended? -

i have working boost.signals2 signal & slot combination in c++ project & set so;

//declare signal signals2::signal<void (const en_data_stream, long, double, double, double, double,     double)> signal;  //connect dataupdate() of candidate instance signal.connect(bind(&candidate::dataupdate, candidateinstance, _1, _2, _3, _4, _5, _6, _7));  //fire signal signal(idatanumber, barnumber(), datetime(), open(), high(), low(), close()); 

i've been trying take further , use boost.signals2 connect_extended functionality i'd pass details of invoking signal slot slot may disconnect signal @ later time. syntax escaping me. please demonstrate how convert above code uses connect_extended pass connection information slot.

p.s. i've been looking @ example provided @ boost website still none wiser how tailor requirements parameters use bind.

boost.signals2 connect_extended example

thanks

the advantage of connect_extended allows slot receive connection object, may crucial in multi-threaded program, slot invocation might occur in thread before connect_extended returns. not need connect_extended pass other information, can bind directly. anyway, here how can connect_extended:

#include <boost/signals2.hpp>  using namespace boost::signals2;  void your_slot(connection conn, int, double, int, char) { }  int main() {   signal<void(int, double, int)> your_signal;   your_signal.connect_extended(boost::bind(&your_slot, _1, _2, _3, _4, 'a'));   your_signal(1, 2.0, 3); }