Re: [Boost-users] [serialization] Different behaviors between archive and its polymorphic variant

Subject: Re: [Boost-users] [serialization] Different behaviors between archive and its polymorphic variant
From: Maxime van Noppen (maxime_at_[hidden])
Date: 2010-08-19 04:52:54

On 08/18/2010 08:33 PM, Robert Ramey wrote:
> 
>>> So now 'unit' only has a template serialize method, but I still
>>>
>>>> int main()
>>>> {
>>>>   unit u(42);
>>>>
>>>>   {
>>>>     std::cout << "template:" << std::endl;
>>>>     test_oarchive ar(std::cout);
>>>>     ar << BOOST_SERIALIZATION_NVP(u);
>>>>     std::cout << std::endl;
>>>>   }
>>>>
>>>>   {
>>>>     std::cout << "polymorphic:" << std::endl;
>>>>     polymorphic_test_oarchive ar(std::cout);
>>>>     ar << BOOST_SERIALIZATION_NVP(u);
>>>>     std::cout << std::endl;
>>>>   }
>>>> }
>>>
>>> Which outputs:
>>>
>>>> template:
>>>> <name=u><name=id_>42</name=id_>
>>>> </name=u>
>>>>
>>>> polymorphic:
>>>> 42
>>>
>>> Code is attached.
> 
> what happens when you try:
> 
> std::cout << "polymorphic:" << std::endl;
> polymorphic_oarchive & po = polymorphic_test_oarchive ar(std::cout);
> po  << BOOST_SERIALIZATION_NVP(u);
> std::cout << std::endl;
> 
> This would actually be using the polymorphic interface as it's
> intended to be used by routing the serialization through the polymorphic
> interface.
> 
> Robert Ramey
> 
> 
> 
> _______________________________________________
> Boost-users mailing list
> Boost-users_at_[hidden]
> http://lists.boost.org/mailman/listinfo.cgi/boost-users

I added:

>   {
>     std::cout << "polymorphic with polymorphic_oarchive:" << std::endl;
>     polymorphic_test_oarchive ar(std::cout);
>     boost::archive::polymorphic_oarchive & po = ar;
>     po << BOOST_SERIALIZATION_NVP(u);
>     std::cout << std::endl;
>   }

The output is:

> template:
> <name=u><name=id_>42</name=id_>
> </name=u>
> 
> polymorphic:
> 42
> polymorphic with polymorphic_oarchive:
> 42

-- 
Maxime