Add 'super', another new object type with magical properties.
super(type) -> unbound super object
super(type, obj) -> bound super object; requires isinstance(obj, type)
Typical use to call a cooperative superclass method:
class C(B):
def meth(self, arg):
super(C, self).meth(arg);
diff --git a/Objects/typeobject.c b/Objects/typeobject.c
index 2017b1e..bf2bdc0 100644
--- a/Objects/typeobject.c
+++ b/Objects/typeobject.c
@@ -2998,3 +2998,158 @@
TPSLOT("__init__", tp_init, slot_tp_init);
TPSLOT("__new__", tp_new, slot_tp_new);
}
+
+
+/* Cooperative 'super' */
+
+typedef struct {
+ PyObject_HEAD
+ PyObject *type;
+ PyObject *obj;
+} superobject;
+
+static void
+super_dealloc(PyObject *self)
+{
+ superobject *su = (superobject *)self;
+
+ Py_XDECREF(su->obj);
+ Py_XDECREF(su->type);
+ self->ob_type->tp_free(self);
+}
+
+static PyObject *
+super_getattro(PyObject *self, PyObject *name)
+{
+ superobject *su = (superobject *)self;
+
+ if (su->obj != NULL) {
+ PyObject *mro, *res, *tmp;
+ descrgetfunc f;
+ int i, n;
+
+ mro = ((PyTypeObject *)(su->obj->ob_type))->tp_mro;
+ assert(mro != NULL && PyTuple_Check(mro));
+ n = PyTuple_GET_SIZE(mro);
+ for (i = 0; i < n; i++) {
+ if (su->type == PyTuple_GET_ITEM(mro, i))
+ break;
+ }
+ assert(i < n);
+ i++;
+ res = NULL;
+ for (; i < n; i++) {
+ tmp = PyTuple_GET_ITEM(mro, i);
+ assert(PyType_Check(tmp));
+ res = PyDict_GetItem(
+ ((PyTypeObject *)tmp)->tp_defined, name);
+ if (res != NULL) {
+ Py_INCREF(res);
+ f = res->ob_type->tp_descr_get;
+ if (f != NULL) {
+ tmp = f(res, su->obj, res);
+ Py_DECREF(res);
+ res = tmp;
+ }
+ return res;
+ }
+ }
+ }
+ return PyObject_GenericGetAttr(self, name);
+}
+
+static PyObject *
+super_descr_get(PyObject *self, PyObject *obj, PyObject *type)
+{
+ superobject *su = (superobject *)self;
+ superobject *new;
+
+ if (obj == NULL || obj == Py_None || su->obj != NULL) {
+ /* Not binding to an object, or already bound */
+ Py_INCREF(self);
+ return self;
+ }
+ new = (superobject *)PySuper_Type.tp_new(&PySuper_Type, NULL, NULL);
+ if (new == NULL)
+ return NULL;
+ Py_INCREF(su->type);
+ Py_INCREF(obj);
+ new->type = su->type;
+ new->obj = obj;
+ return (PyObject *)new;
+}
+
+static int
+super_init(PyObject *self, PyObject *args, PyObject *kwds)
+{
+ superobject *su = (superobject *)self;
+ PyObject *type, *obj = NULL;
+
+ if (!PyArg_ParseTuple(args, "O!|O:super", &PyType_Type, &type, &obj))
+ return -1;
+ if (obj == Py_None)
+ obj = NULL;
+ if (obj != NULL && !PyType_IsSubtype(obj->ob_type,
+ (PyTypeObject *)type)) {
+ PyErr_SetString(PyExc_TypeError,
+ "super(type, obj) requires isinstance(obj, type)");
+ return -1;
+ }
+ Py_INCREF(type);
+ Py_XINCREF(obj);
+ su->type = type;
+ su->obj = obj;
+ return 0;
+}
+
+static char super_doc[] =
+"super(type) -> unbound super object\n"
+"super(type, obj) -> bound super object; requires isinstance(obj, type)\n"
+"Typical use to call a cooperative superclass method:\n"
+"class C(B):\n"
+" def meth(self, arg):\n"
+" super(C, self).meth(arg)";
+
+PyTypeObject PySuper_Type = {
+ PyObject_HEAD_INIT(&PyType_Type)
+ 0, /* ob_size */
+ "super", /* tp_name */
+ sizeof(superobject), /* tp_basicsize */
+ 0, /* tp_itemsize */
+ /* methods */
+ super_dealloc, /* tp_dealloc */
+ 0, /* tp_print */
+ 0, /* tp_getattr */
+ 0, /* tp_setattr */
+ 0, /* tp_compare */
+ 0, /* tp_repr */
+ 0, /* tp_as_number */
+ 0, /* tp_as_sequence */
+ 0, /* tp_as_mapping */
+ 0, /* tp_hash */
+ 0, /* tp_call */
+ 0, /* tp_str */
+ super_getattro, /* tp_getattro */
+ 0, /* tp_setattro */
+ 0, /* tp_as_buffer */
+ Py_TPFLAGS_DEFAULT, /* tp_flags */
+ super_doc, /* tp_doc */
+ 0, /* tp_traverse */
+ 0, /* tp_clear */
+ 0, /* tp_richcompare */
+ 0, /* tp_weaklistoffset */
+ 0, /* tp_iter */
+ 0, /* tp_iternext */
+ 0, /* tp_methods */
+ 0, /* tp_members */
+ 0, /* tp_getset */
+ 0, /* tp_base */
+ 0, /* tp_dict */
+ super_descr_get, /* tp_descr_get */
+ 0, /* tp_descr_set */
+ 0, /* tp_dictoffset */
+ super_init, /* tp_init */
+ PyType_GenericAlloc, /* tp_alloc */
+ PyType_GenericNew, /* tp_new */
+ _PyObject_Del, /* tp_free */
+};