[C++-sig] Trying to clone Python object from C++ (again)

[Paul F. Kunz]

>>>>> On Thu, 21 Jul 2005 15:27:59 -0400, David Abrahams <dave at boost-consulting.com> said:

> "Paul F. Kunz" <Paul_Kunz at slac.stanford.edu> writes:
>> I'm trying once again to clone a Python object whose class is
>> derived from an exposed C++ base class from C++.  After I call from
>> C++ clone() on the base class pointer, I wind up here...
>> 
>> FunctionBase * FunctionWrap:: clone () const { #ifndef
>> HAVE_OLD_PYTHON PyGILState_STATE state = PyGILState_Ensure ();
>> object py_result;
>> 
>> if (override clone = this->get_override("clone"))
>>  { 
>>    try { 
>>   // The Python class author overrode clone; do
>>    // whatever she says
>>      py_result = clone();
>>    } catch ( error_already_set & e )  { 
>>      return 0;
>>    }
>>  } else
>> 
>> (thanks to Dave for essentially writing this for me).

> I wrote that??  I wouldn't want to take responsibility for that
> try/catch block.  It just discards all the information about what
> happened.

   Ok, *I* added the try/catch block around the code you helped me
with a long time ago.   Apologies.

>> The problem is that the exception is thrown.

> Which exception?

The error_already_set exception is always thrown.

>   if (override clone = this->get_override("clone")) { // The Python
> class author overrode clone; do // whatever she says try { py_result
> = clone(); } catch ( error_already_set & e ) { PyErr_Print(); return
> 0 } } else

   I'll try the PyErr_Print to see what I get.   Thanks.