Greetings,
I have used a method mentioned on stackoverflow
(http://stackoverflow.com/questions/6908976/generalized-exception-translation-for-boost-python)
for a generalized method to translate C++ exceptions to python exceptions.
When debugging my code using gdb the frames seem to indicate that a C++
requires a call to all of the translation instances. Is this because of
a Boost.Python implementation issue, my deriving all my python
exceptions from PyExc_EnvironmentError (using PyErr_NewException), or
possibly a misunderstanding I have about C++ and template function
evaluations?
My code for a generic approach is:
template<class E>
class GeneralizedTranslator{
public:
GeneralizedTranslator(PyObject* py_exc): A_PyExc(py_exc)
{
bp::register_exception_translator<E>(*this);
}
GeneralizedTranslator(const GeneralizedTranslator &other)
: A_PyExc(other.A_PyExc)
{ ; }
void
operator()(const E &my_error) const
{
std::stringstream ostr;
ostr << boost::diagnostic_information(my_error);
PyErr_SetString(A_PyExc, ostr.str().c_str());
}
private:
PyObject *A_PyExc;};
// Allow for a simple translation declaration, remove scope problem
template <class ErrType> void
translate_error(PyObject *E)
{
GeneralizedTranslator<ErrType> my_translator(E);
}
New exceptions are created by:
PyObject *PyExc_Error_A =
PyError_NewException("Exception_A", PyExc_EnvironmentError, NULL);
The class is used as:
BOOST_PYTHON_MODULE(_test)
{
// Here the exceptions (My_Exception_*) are derived from
boost::exception and std::exception
translate_error<My_Exception_A>(PyExc_Error_A);
translate_error<My_Exception_B>(PyExc_Error_B);
.
.
.
}
In gdb I see:
.
.
.
#52 0x00007fffeff04827 in
boost::detail::function::function_obj_invoker2<boost::_bi::bind_t<bool,
boost::python::detail::translate_exception<My_Exception_B,
GeneralizedTranslator<My_Exception_B> >,
boost::_bi::list3<boost::arg<1>, boost::arg<2>,
boost::_bi::value<GeneralizedTranslator<My_Exception_B> > > >, bool,
boost::python::detail::exception_handler const&, boost::function0<void>
const&>::invoke(boost::detail::function::function_buffer&,
boost::python::detail::exception_handler const&, boost::function0<void>
const&) ()
from /path/to/_test.so
#53 0x00007ffff38a9ef4 in
boost::python::detail::exception_handler::operator()(boost::function0<void>
const&) const ()
from /path/to/libboost_python.so
#54 0x00007fffeff04977 in
boost::detail::function::function_obj_invoker2<boost::_bi::bind_t<bool,
boost::python::detail::translate_exception<My_Exception_A,
GeneralizedTranslator<My_Exception_A> >,
boost::_bi::list3<boost::arg<1>, boost::arg<2>,
boost::_bi::value<GeneralizedTranslator<My_Exception_A> > > >, bool,
boost::python::detail::exception_handler const&, boost::function0<void>
const&>::invoke(boost::detail::function::function_buffer&,
boost::python::detail::exception_handler c
onst&, boost::function0<void> const&) ()
from /path/to/_test.so
#55 0x00007ffff38a9cfa in
boost::python::handle_exception_impl(boost::function0<void>) ()
from /path/to/libboost_python.so
#56 0x00007ffff38983e8 in ?? ()
from /path/to/libboost_python.so
#57 0x000000000041ef47 in PyObject_Call ()
#58 0x00000000004a72b8 in PyEval_EvalFrameEx ()
#59 0x00000000004a95c1 in PyEval_EvalCodeEx ()
#60 0x00000000004a7752 in PyEval_EvalFrameEx ()
.
.
.
Thanks,
Jeff Van Voorst
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