Re: [Boost-users] [serialization] serializing a pointer without causingobject tracking

Subject: Re: [Boost-users] [serialization] serializing a pointer without causingobject tracking
From: Robert Ramey (ramey_at_[hidden])
Date: 2013-03-30 14:03:24

Stefan Strasser wrote:
> Hi everyone,
> Hi Robert, in case you'd like to answer this one, because I have a
> rather specific question about your library. Thank you in advance!
>
>
> I'd like to serialize an object and later reconstruct it from the
> serialized data:
>
> void save(T const &t){ ar << t; }
> T* load(){
>   T *t=new T(); //error
>   ar >> *t;
> }
>
> T might not have a default constructor.
> so load_construct_data should be used. apparently the way to do this
> is to serialize through a pointer:
>
> void save(T const *t){ ar << t; }
> T *load(){
>   T *t;  ar >> t;
> }
>
> this works, but it causes the type T to be tracked, if its object
> tracking is set to track_selectively.
> I don't want that. but I can't set it to track_never either, because
> if the type is serialized at another point in the program through a
> pointer, the type should be tracked.
>
> is there a solution to this? is there a serialization wrapper that
> says "don't track this type just because of this pointer"?

so you want "don't track this particular save - but leave others as normal"

Try something like

class A ....

class UntrackedA : public A {
...
};

BOOST_SERIALIZATION_TRACK(UntrackedA, track_never);

..

A a;
const Untracked & A ua(a);
ar << ua;
...

Untracked & A ua2(a);
ar >> ua2;

That would what would first occur to me.

Robert Ramey