#ifdef __cplusplus /* SwigPtr_PyObject is used as a replacement of PyObject *, where the INCREF/DECREF are applied as needed. You can use SwigPtr_PyObject in a container, such as std::vector<SwigPtr_PyObject>; or as a member variable: struct A { SwigPtr_PyObject obj; A(PyObject *o) : _obj(o) { } }; or as a input/output value SwigPtr_PyObject func(SwigPtr_PyObject obj) { SwigPtr_PyObject out = PyString_FromFormat("hello %s", PyObject_AsString(obj)); Py_DECREF(out); return out; } just remember to pair the object creation with the proper DECREF, the same as with plain PyObject *ptr, since SwigPtr_PyObject always add one reference at construction. SwigPtr_PyObject is 'visible' at the wrapped side, so you can do: %template(pyvector) std::vector<swig::SwigPtr_PyObject>; and all the proper typemaps will be used. */ namespace swig { %ignore SwigPtr_PyObject; struct SwigPtr_PyObject {}; %apply PyObject * {SwigPtr_PyObject}; %apply PyObject * const& {SwigPtr_PyObject const&}; %typemap(typecheck,precedence=SWIG_TYPECHECK_SWIGOBJECT,noblock=1) SwigPtr_PyObject const& "$1 = ($input != 0);"; /* For output */ %typemap(out,noblock=1) SwigPtr_PyObject { $result = (PyObject *)$1; Py_INCREF($result); } %typemap(out,noblock=1) SwigPtr_PyObject const & { $result = (PyObject *)*$1; Py_INCREF($result); } } %{ namespace swig { class SwigPtr_PyObject { protected: PyObject *_obj; public: SwigPtr_PyObject() :_obj(0) { } SwigPtr_PyObject(const SwigPtr_PyObject& item) : _obj(item._obj) { Py_XINCREF(_obj); } SwigPtr_PyObject(PyObject *obj, bool initial_ref = true) :_obj(obj) { if (initial_ref) { Py_XINCREF(_obj); } } SwigPtr_PyObject & operator=(const SwigPtr_PyObject& item) { Py_XINCREF(item._obj); Py_XDECREF(_obj); _obj = item._obj; return *this; } ~SwigPtr_PyObject() { Py_XDECREF(_obj); } operator PyObject *() const { return _obj; } PyObject *operator->() const { return _obj; } }; } %} /* SwigVar_PyObject is used to manage 'in the scope' PyObject * variables, as in int func () { SwigVar_PyObject obj = PyString_FromString("hello"); } ie, 'obj' is created and destructed in the same scope from a python object that carries at least one reference value. SwigVar_PyObject just take care of applying the proper Py_DECREF. Hence, this class is purely internal and not visible at the wrapped side. */ namespace swig { %ignore SwigVar_PyObject; struct SwigVar_PyObject {}; %apply PyObject * {SwigVar_PyObject}; %apply PyObject * const& {SwigVar_PyObject const&}; } %{ namespace swig { struct SwigVar_PyObject : SwigPtr_PyObject { SwigVar_PyObject(PyObject* obj = 0) : SwigPtr_PyObject(obj, false) { } SwigVar_PyObject & operator = (PyObject* obj) { Py_XDECREF(_obj); _obj = obj; return *this; } }; } %} #endif