Re: [Boost-users] [serialization] skipping data

From: Robert Ramey (ramey_at_[hidden])
Date: 2006-07-10 11:08:48

Joel de Guzman wrote:
> Peter Dimov wrote:

>> You need to define a proxy Y object that can deserialize itself into
>> thin air.

Very clever - I'm embarassed I didn't think about that.

> I thought about that. But that would mean that blank_proxy<Y>
> knows all about Y -- its composition down to the leaves -- and
> wrap them all as blank_proxy<T>s. A hairy proposition, IMO.

Hmm - sounds like one needs proxy objects for all of Y's members
and so one down to the primitive leaves.

And here's another idea.

create an archive adaptor which takes any archive and replaces
its loading of primitives to something that just throws them away.

so at some point one would try

load(Archive & ar, Y & y,  const unsigned version){
    ar >> x;
    if(version == 1){
        dummy_archive<Archive> da(ar);
        da >>y;
    }
    ar >> z;
}

I havn't written documentation on archive adaptor but
polymorphic_?archives are examples of such a thing.

Robert Ramey