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

From: Joel de Guzman (joel_at_[hidden])
Date: 2006-07-10 10:07:51

Peter Dimov wrote:
> Joel de Guzman wrote:
>> Hi,
>>
>> Here's a use case that I can't seem to find a way to
>> do using boost.serialization.
>>
>> Say with version 1, I want to serialize X Y and Z. These
>> are hierarchical and expensive data structures. Now, with
>> version 2, I do not need to create Y objects anymore. Yet,
>> I still have to open version 1 files for backward compatibility.
>> So, when loading version 1 files, I want to skip reading Y
>> objects. How do I do that without having to create a temporary
>> Y object that will be discarded later?
> 
> You need to define a proxy Y object that can deserialize itself into thin 
> air. 

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.

Regards,
-- 
Joel de Guzman
http://www.boost-consulting.com
http://spirit.sf.net