J>      void intrusive_ptr_add_ref(T * p);
J>      void intrusive_ptr_release(T * p);
J>

namespace intrusive_ptr_details
{
   struct IntrusiveCounter
   {
      IntrusiveCounter() : count( 0 ) {}
      IntrusiveCounter( IntrusiveCounter const & ) : count( 0 ) {} 
      IntrusiveCounter & operator=( IntrusiveCounter const & ) { return *this; }
      size_t count;
   };
}

#define DECLARE_INTRUSIVE_COUNTER(name)                                            \
   intrusive_ptr_details::IntrusiveCounter _ptr_count_;                                \
   friend void intrusive_ptr_add_ref( name * p ) { ++p->_ptr_count_.count; }                \
   friend void intrusive_ptr_release( name * p ) { if( --p->_ptr_count_.count == 0 ) delete p; } 

#define INTRUSIVE_SMART_PTR(name) boost::intrusive_ptr<name>

#define DECLARE_INTRUSIVE_COUNTER_MUTABLE(name)                                          \
   mutable intrusive_ptr_details::IntrusiveCounter _ptr_count_;                              \
   friend void intrusive_ptr_add_ref( name const * p ) { ++p->_ptr_count_.count; }                \
   friend void intrusive_ptr_release( name const * p ) { if( --p->_ptr_count_.count == 0 ) delete p; } 

#define INTRUSIVE_SMART_PTR_CONST(name) boost::intrusive_ptr<name const>

struct A
{
DECLARE_INTRUSIVE_COUNTER(A)
};

typedef INTRUSIVE_SMART_PTR(A) APtr;