#include <boost/enable_shared_from_this.hpp>
#include <boost/make_shared.hpp>
#include <boost/smart_ptr.hpp>

#include <iostream>

class base :
		public boost::enable_shared_from_this<base>
{
public:
	boost::shared_ptr<base> get_shared_from_base()
	{
		return shared_from_this();
	}
};

class derived :
		public base,
		public boost::enable_shared_from_this<derived>
{
public:
	boost::shared_ptr<derived> get_shared_from_derived()
	{
		return boost::enable_shared_from_this<derived>::shared_from_this();
	}
};

int main()
{
	boost::shared_ptr<derived> thing = boost::make_shared<derived>();
	
	boost::shared_ptr<derived> derived_thing = thing->get_shared_from_derived();
	boost::shared_ptr<base> base_thing = thing->get_shared_from_base();
	
	return 0;
}