help with Python C-API, tuple object

[Carsten Haese]

On 11 May 2007 21:11:06 -0700, fabian.conrad wrote
> Hi,
> sorry for the rather basic question but I've searched everywhere and
> don't find an answer.
> I want to call PyObject_CallObject from the Python C-API and pass a
> tuple I've created from a C-array
> 
> How can I pass the tuple as an object rather then having to declare
> the python function with the number of arguments equal to the no of
> elements in the tuple?

The documentation at http://docs.python.org/api/object.html lists various Call
flavors. The one you chose will unpack the tuple as if you called
pFunc(*pArgs), which results in the undesired behavior of pFunc receiving
three arguments. You want it to receive one argument that is the tuple pArgs.

One (bad) way of achieving this would be to build another tuple of size one,
stick pArgs into it, and pass that size-one tuple to PyObject_CallObject. A
better way is to use PyObject_CallFunctionObjArgs. If I'm not mistaken, you'll
want something like

pValue = PyObject_CallFunctionObjArgs(pFunc, pArgs, NULL);

Hope this helps,

--
Carsten Haese
http://informixdb.sourceforge.net