Re: [Boost-users] boost serialization: can't deserialize pointer to abstract base class where derived classes overload load_construct_data

Subject: Re: [Boost-users] boost serialization: can't deserialize pointer to abstract base class where derived classes overload load_construct_data
From: Robert Ramey (ramey_at_[hidden])
Date: 2013-01-08 21:03:49

Rebecca Lehman wrote:
> Does anyone have an example of how to serialize such pointers?
> 

Here are some observations on your email

a) note that the issues related to pointers and non-default constructors
or orthogonal so you actually have two separate problems here.

b) non-default constuctors.  Check out files in the ...../libs/serialization/test directory:
test_non_default_ctor and test_non_default_ctor2.  Make a small program
to test your serialization - don't use pointers just make sure the
basic serialization works.

c) pointers.  The system is designed to permit serialization through an 
abstract pointer to a base class.  However, it does require some care

1) there are two methods - "register" and "export" - you've used both
in our example. I recommend using one or the other just to keep
from getting too confused.

2) remember if you serialize through a derived pointer you can't 
de-serialize through the base class.  That is, you always have
to de-serialize to the exact same type you serialized from.

3) your example shows
class D2 {
...
};
BOOST_CLASS_EXPORT_GUID(D1, "D1"); // should be D2 !!!

check out ...../libs/serialization/test/test_exported.cpp for an example.

Robert Ramey