Re: [Boost-users] [Serialization] [Serialization of stl map withpointer to POD type]

Subject: Re: [Boost-users] [Serialization] [Serialization of stl map withpointer to POD type]
From: Robert Ramey (ramey_at_[hidden])
Date: 2008-12-30 21:02:06

Anytime you're serialization a "const" value its a red flag that
you might really want to do that. "const" values are
initialized when the object is created and should never
subsequently change.

anyway, try:

save ..
ar << data.count();.
for (iter = data_.begin(); iter != data_.end(); iter++) {
    std::string key(iter->first);
    ar << key;
    ar << iter->second;
}

load ...
_data.clear()
ar >> count;
while(0 < count){
    std::string key;
    int i;
    ar >> key;
    ar >> i;
    data_.insert(
        key.cstr(),  // of course this won't work - but you get the idea
        i
    );
}

Robert Ramey

Denis Gabaidulin wrote:
> I have following class with stl container:
>
> class storage : {
> private:
>   map<const char*, int, cmp> data_;
>
>   friend class boost::serialization::access;
>
>    template<class Archive>
>    void save(Archive & ar, const unsigned int version) const
>    {
>        map<string, int> local;
>        constDataIter iter;
>
>        for (iter = data_.begin(); iter != data_.end(); iter++) {
>           local[iter->first] = iter->second;
>        }
>
>        ar & local;
>    }
> }
>
> This code works, but it slowly(full copy) and consume too much memory
> (x2) :-(
>
> What is the best serialization strategy with such stl containers or
> pointer to pod type?
>
> I cannot change const char* to string, dont ask me why :-))
>
> Thanks you for any advice.