[Boost-users] Re: Serialization, shared_ptr and namespaces

From: Jan Eickmann (je_at_[hidden])
Date: 2005-05-03 15:43:57

Hello,

sorry to bump this but I still haven't found a solution or any 
information on how to use shared_ptr together with serialization.

Anybody can shed some light on this?

Thanks a lot,

Jan Eickmann

Jan Eickmann wrote:
> Hi,
> 
> I'm trying to serialize a list of shared_ptr's to objects.
> 
> Here's a summary of the code I have:
> 
> namespace MyNamespace
> {
> 
> class B
> {
> //implementation plus standard serialization function
> };
> 
> class A
> {
> private:
>     list< shared_ptr<B> > myBs;
> public:
>     template<class Archive>
>     void serialize(Archive & ar, const unsigned int version)
>     {
>         ar & BOOST_SERIALIZATION_NVP(myBs);
>     }
> };
> 
> }
> 
> If I just try to serialize it, I get an unregistered_class exception. So 
> I think I have to use BOOST_SHARED_POINTER_EXPORT(_GUID) to register the 
> shared_ptr.
> 
> When I include this inside the namespace (please note that the error 
> messages are from my real code, so they have slightly other names:
> 
> BOOST_SHARED_POINTER_EXPORT(B)
> 
> I get this:
>  f:\xenocide\xenocide\src\common\simulation\simulation.h(108) : error 
> C2059: syntax error : 'string'
> f:\xenocide\xenocide\src\common\simulation\simulation.h(108) : error 
> C2146: syntax error : missing ';' before identifier 
> 'BOOST_CLASS_EXPORT_GUID'
> f:\xenocide\xenocide\src\common\simulation\simulation.h(108) : error 
> C2059: syntax error : 'string'
> f:\xenocide\xenocide\src\common\simulation\simulation.h(109) : error 
> C2143: syntax error : missing ';' before '}'
> 
> When I put it outside the namespace I have to use a fully qualified name 
> including the namespace for class B, so it becomes
> 
> BOOST_SHARED_POINTER_EXPORT(MyNamespace::B)
> 
> Then I get (not Xenocide is here what MyNamespace is in my example):
> f:\xenocide\xenocide\src\common\simulation\simulation.h(115) : error 
> C2653: '__shared_ptr_Xenocide' : is not a class or namespace name
> f:\xenocide\xenocide\src\common\simulation\simulation.h(115) : error 
> C2653: '__shared_ptr_Xenocide' : is not a class or namespace name
> 
> I also tried various combinations with BOOST_SHARED_POINTER_EXPORT_GUID 
> but it didn't help.
> 
> Can someone explain to me how I have to declare shared_ptr's in order 
> for them to work with boost::serialization? I was unable to find some 
> more indepth documentation.
> 
> Thanks,
> 
> Jan Eickmann