Re: [xml-cppdom-devel] Another Win32-related change

[Allen B. <al...@vr...>]

Patrick Hartling wrote:
> A problem has arisen with CppDOM on Win32, most likely because of the 
> change I made for the import/export stuff for the CppDOM DLL.  It has 
> come to my attention that cppdom::Attributes derives from std::map<>. 
> (More specifically, it derives from std::map<std::string, std::string>).
> 
> If there is code that links against CppDOM that also uses the type 
> std::map<std::string, std::string>, the VC++ 7 linker complains of 
> multiply defined symbols, all of them in the std::map<> class.  It is my 
> understanding that deriving from STL types is not recommended, and in my 
> (limited) experience, DLLs and templates as base types do not mix well.
> 
> So, my proposed change is to fix cppdom::Attributes so that it 
> aggregates std::map<std::string, std::string> instead of extending it. 
> The API for cppdom::Attributes has to be extended a little to have some 
> pass-through methods into the std::map<> interface.  I have already made 
> this change and tested it successfully, and I want to know if it is okay 
> to commit it.  I'm sure my changes aren't very elegant, but they get the 
> job done.

I like the idea.

It would also allow us to internally use a hash_map when the platform 
supports it.

-Allen

>  -Patrick
> 
> 


-- 
-- Allen Bierbaum                         al...@vr...
-- PhD Candidate             txtmsg - 515...@us...
-- VR Juggler Team                              www.vrjuggler.org
-- Virtual Reality Applications Center       www.vrac.iastate.edu