Re: [Boost-users] Problems using boost serializing and customconstructors

Subject: Re: [Boost-users] Problems using boost serializing and customconstructors
From: Robert Ramey (ramey_at_[hidden])
Date: 2012-03-12 13:26:29

Allan Nielsen wrote:
> Hi again,
>
> I have now tried to get your suggested solution to work, but did not
> succeed.
>
>> template<typename Archive>
>> void serialize(Archive &ar, const unsigned int) {
>> auto * data_ptr = &data;
>> ar & data_ptr; // load and save through pointer
>>
>> if(Archive::is_loading::value) {
>> data = std::move(*data_ptr); // no-throw
>> ar.reset_object_address(&data, data_ptr);
>> delete data_ptr; // not sure here
>> }
>
> This produced a compiler error, so I slitted it into separated load
> and save methods which looks like this:
>
>    BOOST_SERIALIZATION_SPLIT_MEMBER();
>
>    template<class Archive>
>    void save(Archive & ar, const unsigned int version) const
>    {
>        const std::vector<unsigned> * data_ptr = &data;
>        ar & data_ptr; // load and save through pointer
>    }
>
>    template<class Archive>
>    void load(Archive & ar, const unsigned int version)
>    {
>        const vector<int> * data_ptr;
>        ar & data_ptr; // load and save through pointer
>        data = std::move(*data_ptr); // no-throw
>        ar.reset_object_address(&data, data_ptr);
>        delete data_ptr;
>    }
>

This whole thing looks a little suspicious to me.  I'd have to spend
considerable time looking into it.  But I'm curious why you don't
just do the following:

template<class Archive>
void save(Archive &ar, const unsigned int version) const {
    ar << data;
}

template<class Archive>
void load(Archive &ar, const unsigned int version){
    ar >> data;
}

> Also, if I add:
>
> BOOST_STATIC_ASSERT( (boost::serialization::tracking_level< const
> std::vector<unsigned> * >::value != boost::serialization::track_never)
> );
>
> I get an compiler error saying static assert failed. Why is that?
> shouldn't everything serialized through a pointer be tracked?

again, I'd have to look into this more deeply.  I'm a little
intriqued with serilization of

>        const vector<int> * data_ptr;

I guess it's ok but it's sort of wierd to load a pointer
to a CONST.

Robert Ramey

> What can I do to fix this?
>
> Best regards
> Allan W. Nielsen
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