#include <boost/signals2.hpp>
#include <boost/make_shared.hpp>
#include <boost/shared_ptr.hpp>

struct A
{ boost::signals2::signal<void()> Signal; };
struct B
{ boost::signals2::signal<void()> Signal; };

int main()
{
	
	boost::shared_ptr<A> pA = boost::make_shared<A>();
	boost::shared_ptr<B> pB = boost::make_shared<B>();

	pA->Signal.connect(pB->Signal);
	pA->Signal();
	pB.reset();
	pA->Signal();

	return 0;
}