Boost Exception

#include <boost/exception/exception.hpp>

namespace
boost
    {
    class
    unknown_exception:
        public std::exception
        public boost::exception
        {
        ---unspecified---
        };    
    
    typedef error_info<struct tag_original_exception_type,std::type_info const *> original_exception_type;    
    
    typedef ---unspecified--- exception_ptr;    
    
    template <class T>
    exception_ptr copy_exception( T const & e );    
    
    exception_ptr current_exception();    
    
    void rethrow_exception( exception_ptr const & ep );
    }