Re: [Boost-users] [Serialization] Strange warning + serialization of template derived class

Subject: Re: [Boost-users] [Serialization] Strange warning + serialization of template derived class
From: Robert Ramey (ramey_at_[hidden])
Date: 2010-02-13 15:15:54

dada_at_[hidden] wrote:
> Hi all,
>
> First problem:
> --------------
> i have this warning.
> "...... boost/mpl/print.hpp:55: warning: comparison between signed and
> unsigned integer expressions"

the serialization library used this to indicate usage of the library which
is permited though probably not a good idea.  Check the compile
error listing to find what calls this.  This should show some place
where BOOST_SERIALIZATION_STATIC_WARNING is
invoked.  There you should find an explanation of why such a
warning was emitted.

>
> Second problem:
> ---------------
> I want to serialize a template derivate class like this:
>
>
> ////////////////////////////
> class Base
> {
>   private:
>     friend class boost::serialization::access;
>
>     template<class Archive>
>     void serialize(Archive &, const unsigned int )
>     {
>     }
> };
>
> template<typenmame T>
> class Child: public Base
> {
>   private:
>     friend class boost::serialization::access;
>
>     template<class Archive>
>     void serialize(Archive &ar, const unsigned int )
>     {
>       ar & BOOST_SERIALIZATION_BASE_OBJECT_NVP(Base);
>     }
> };
>
> BOOST_CLASS_EXPORT_GUID(Child<int>, "Child")//don't work
> ///////////////////////////
>
> The macro "BOOST_CLASS_EXPORT_GUID" don't work with template class.
> Is there a way to do this ?

I would guess that the <> characters are some sort of problem.  Try
typedef Child<int> Child_int

BOOST_CLASS_EXPORT_GUID(Child_int, "ChildInt) // remember the name has to be 
unique!!

Also there is a track item with a suggestion on how to implement the 
equivalent of:

BOOST_CLASS_EXPORT(Child<int>)

Robert Ramey

> Thank you,
> Regards,
> Damien.