[C++-sig] bad exception conversion

June 13, 2012


      I have some glue code that calls a C++ function which can raise an 
unsuitable_error exception. I have an exception translator which will 
convert that to a more pythonic version (UnsuitableError), but when I 
use that I get an "SystemError: 'finally' pops bad exception" error on 
the python side. As far as I can see my code looks correct, but I 
suspect I am overlooking something trivial somewhere.


using namespace boost::python;

class UnsuitableError : public std::exception {
public:
     UnsuitableError() : reasons() { }
     ~UnsuitableError() throw() {}
     boost::python::list reasons;
};

namespace {
     PyObject *UnsuitableErrorType = NULL;

     void translator(const unsuitable_error &e) {
         std::list<const char*>::const_iterator i;
         PyObject* unicode;
         UnsuitableError error=UnsuitableError();
         for (i=e.reasons.begin(); i!=e.reasons.end(); i++) {
             unicode = PyUnicode_FromString(*i);
             
error.reasons.append(boost::python::object(boost::python::handle<>(unicode)));
         }

         boost::python::object exc(error);
         PyErr_SetObject(UnsuitableErrorType, exc.ptr());
     }
}


void export() {
     object module(handle<>(borrowed(PyImport_AddModule("mypkg.article"))));
     scope().attr("article")=module;
     scope module_scope = module;

     class_<UnsuitableError> UnsuitableErrorClass("UnsuitableError");
     UnsuitableErrorClass.def_readonly("reasons", 
&UnsuitableError::reasons);
     UnsuitableErrorType=UnsuitableErrorClass.ptr();

     register_exception_translator<unsuitable_error>(&translator);
}

[C++-sig] bad exception conversion

Wichert Akkerman