# Boost Exception

### throw_exception

#include <boost/throw_exception.hpp>

    namespace
    boost
        {
    #ifdef BOOST_NO_EXCEPTIONS
        void throw_exception( std::exception const & e ); // user defined
    #else
        template <class E>
        void throw_exception( E const & e );
    #endif
        }

#### Effects:

- If BOOST_NO_EXCEPTIONS is not defined, boost::throw_exception(e) throws an exception of unspecified type that derives publicly from E and from boost::exception.
- If BOOST_NO_EXCEPTIONS is defined, the function is left undefined, and the user is expected to supply an appropriate definition. Callers of throw_exception are allowed to assume that the function never returns; therefore, if the user-defined throw_exception returns, the behavior is undefined.

#### Requirements:

E must derive publicly from std::exception. E may or may not derive from boost::exception.

#### Notes:

- The emitted exception can be intercepted as E &, std::exception &, or boost::exception &.
- The emitted exception supports boost::exception_ptr.
- If BOOST_EXCEPTION_DISABLE is defined and BOOST_NO_EXCEPTIONS is not defined, boost::throw_exception(e) equivalent to throw e.

See also: BOOST_THROW_EXCEPTION | Boost Exception | boost/throw_exception.hpp | Configuration Macros | enable_current_exception | Frequently Asked Questions | Transporting of Exceptions Between Threads