[C++-sig] Wrappend objects identity problem

[Victor Nakoryakov]

Victor Nakoryakov wrote:
> Ok, I think my previous post was too complicated, here is simplified 
> version:
> 
> 
>>class A
>>{
>>};
>>
>>boost::shared_ptr<A> ptr;
>>boost::shared_ptr<A> getA()
>>{
>>	if (!ptr)
>>		ptr = boost::shared_ptr<A>(new A);
>>
>>	return ptr;
>>}
>>
>>void Init()
>>{
>>	python::class_< A, boost::shared_ptr<A>, boost::noncopyable >( "AClass", python::no_init );
>>	python::def("getA", &getA);
>>}
> 
> 
> And py code is:
> 
> 
>>a1 = getA()
>>a2 = getA()
>>l = [a1, a2]
>>print a1
>>print a2
>>print getA() in l
>>print a1 is a2
>>print a1 == a2
> 
> 
> Output is:
> 
> <_mymodule.AClass object at 0x017DB070>
> <_mymodule.AClass object at 0x017DB0B0>  <- another address!
> False
> False
> False
> 
> The question is the same: What I have to do to have the same address of 
> AClass every time I call getA() from python.
> 
> I can't find solution already for 3 days. Have anyone ideas?
> 

Furtermore following C++ code:

> class A
> {
> };
> 
> A* ptr = 0;
> A* getA()
> {
> 	if (!ptr)
> 		ptr = new A;
> 
> 	return ptr;
> }
> 
> void Init()
> {
> 	python::class_< A, boost::noncopyable >( "AClass", python::no_init );
> 	python::def("getA", &getA, python::return_value_policy<python::reference_existing_object>());
> }


Produces the same output! What's wrong?


-- 
Victor (aka nail) Nakoryakov
nail-mail<at>mail<dot>ru

Krasnoznamensk, Moscow, Russia