#включает <boost/qvm/error.hpp> 
include <boost/qvm/error.hpp> 
[ORIG_END] -->

namespace boost
{
    namespace qvm
    {
        //*** Exception types ***
        
        struct error:
            virtual boost::exception,
            virtual std::exception
        {
        };        
        
        struct zero_determinant_error: virtual error { };        
        struct zero_magnitude_error: virtual error { };
    }
}