Re: [Boost-users] [serialization] conflicting declaration(BOOST_CLASS_EXPORT)

Subject: Re: [Boost-users] [serialization] conflicting declaration(BOOST_CLASS_EXPORT)
From: jens weller (jensweller_at_[hidden])
Date: 2008-09-19 11:45:16

Jeff Flinn wrote:
> jens weller wrote:
> 
>> Robert Ramey wrote:
>>
>>> try the following re export:
>>>
>>> a) re-read the manual regarding boost class export
>>
>> I did, any points you think about?
>>
>>> b) Try using BOOST_CLASS_EXPORT only once.
>>
>>
>> So far I thought after each class I could just set a 
>> BOOST_CLASS_EXPORT($classname),
>> as far as its derived from a serializable class.
>> So, how to use it "only once"?
>> Should I put those all in one file instead? ("exportmodel.hpp" f.e.)
> 
> 
> Hi Jens,
> 
> I think Robert means that BOOST_CLASS_EXPORT($classname) may only be 
> expanded once in your program for a particular class name. And per the 
> docs this expansion must occur within the context of all archive types 
> that will be used to serialize the class.
> 
> So rather than placing these macro calls in headers(which may be 
> included in multiple translation units), place them in a cpp file that 
> first includes the desired archive headers. Typically this would be in 
> the class' implementation file. In the past I had placed them all in a 
> single file, but quickly found the MSVC7.1 compiler limits, and had to 
> break them up into export1.cpp, export2.cpp, ...
> 

Thanks Jeff,

putting it in the class.cpp is a solution.

regards,

Jens Weller