[Boost-users] [serialization] Export question

Subject: [Boost-users] [serialization] Export question
From: Tom Aylesworth (taylesworth_at_[hidden])
Date: 2009-04-08 10:55:20

I just want to make sure that I understand the use of the Serialization library's EXPORT macros.  On the "Serializable Concepts" page of the documentation, it states:

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The macro BOOST_CLASS_EXPORT_GUID associates a string literal with a class. ... This permits each class to be in a separate header file along with its string identifier.
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However, on the "Special Considerations" page, I find:
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Note that the implementation of this functionality requires that the BOOST_CLASS_EXPORT macro appear after and the inclusion of any archive class headers for which code is to be instantiated. ... Note that including BOOST_CLASS_EXPORT in the "a.hpp" header itself as one would do with other serialization traits will make it difficult or impossible to follow the rule above regarding inclusion of archive headers before BOOST_CLASS_EXPORT is invoked. This is different than other serialization traits which would normally be included in same file as the class declaration.
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The associated example shows the EXPORT macro following the #include of the header defining the class to be exported.
I would certainly much rather have the EXPORT macros appear in the header with the class that defines them.  I take it that means I have to guarantee that the file actually responsible for operating on an archive includes my headers with the class definitions and EXPORT macros *after* including the appropriate archive headers (e.g., "boost/archive/xml_oarchive.hpp").
Is that correct?  Are there any other gotchas I should be aware of if I place the EXPORT macros in the headers with the classes to be exported?
Thanks,
Thomas Aylesworth
Senior Software Engineer
Reality Mobile