Make int, long and float subclassable.
This uses a slightly wimpy and wasteful approach, but it works. :-)
diff --git a/Objects/intobject.c b/Objects/intobject.c
index 77d7e38..80cdf4b 100644
--- a/Objects/intobject.c
+++ b/Objects/intobject.c
@@ -134,8 +134,12 @@
static void
int_dealloc(PyIntObject *v)
{
- v->ob_type = (struct _typeobject *)free_list;
- free_list = v;
+ if (v->ob_type == &PyInt_Type) {
+ v->ob_type = (struct _typeobject *)free_list;
+ free_list = v;
+ }
+ else
+ v->ob_type->tp_free((PyObject *)v);
}
long
@@ -783,6 +787,9 @@
return PyString_FromString(buf);
}
+staticforward PyObject *
+int_subtype_new(PyTypeObject *type, PyObject *args, PyObject *kwds);
+
static PyObject *
int_new(PyTypeObject *type, PyObject *args, PyObject *kwds)
{
@@ -790,7 +797,8 @@
int base = -909;
static char *kwlist[] = {"x", "base", 0};
- assert(type == &PyInt_Type);
+ if (type != &PyInt_Type)
+ return int_subtype_new(type, args, kwds); /* Wimp out */
if (!PyArg_ParseTupleAndKeywords(args, kwds, "|Oi:int", kwlist,
&x, &base))
return NULL;
@@ -811,6 +819,29 @@
return NULL;
}
+/* Wimpy, slow approach to tp_new calls for subtypes of int:
+ first create a regular int from whatever arguments we got,
+ then allocate a subtype instance and initialize its ob_ival
+ from the regular int. The regular int is then thrown away.
+*/
+static PyObject *
+int_subtype_new(PyTypeObject *type, PyObject *args, PyObject *kwds)
+{
+ PyObject *tmp, *new;
+
+ assert(PyType_IsSubtype(type, &PyInt_Type));
+ tmp = int_new(&PyInt_Type, args, kwds);
+ if (tmp == NULL)
+ return NULL;
+ assert(PyInt_Check(tmp));
+ new = type->tp_alloc(type, 0);;
+ if (new == NULL)
+ return NULL;
+ ((PyIntObject *)new)->ob_ival = ((PyIntObject *)tmp)->ob_ival;
+ Py_DECREF(tmp);
+ return new;
+}
+
static char int_doc[] =
"int(x[, base]) -> integer\n\
\n\
@@ -882,7 +913,8 @@
PyObject_GenericGetAttr, /* tp_getattro */
0, /* tp_setattro */
0, /* tp_as_buffer */
- Py_TPFLAGS_DEFAULT | Py_TPFLAGS_CHECKTYPES, /* tp_flags */
+ Py_TPFLAGS_DEFAULT | Py_TPFLAGS_CHECKTYPES |
+ Py_TPFLAGS_BASETYPE, /* tp_flags */
int_doc, /* tp_doc */
0, /* tp_traverse */
0, /* tp_clear */
@@ -934,7 +966,7 @@
for (i = 0, p = &list->objects[0];
i < N_INTOBJECTS;
i++, p++) {
- if (PyInt_Check(p) && p->ob_refcnt != 0)
+ if (p->ob_type == &PyInt_Type && p->ob_refcnt != 0)
irem++;
}
next = list->next;
@@ -944,7 +976,8 @@
for (i = 0, p = &list->objects[0];
i < N_INTOBJECTS;
i++, p++) {
- if (!PyInt_Check(p) || p->ob_refcnt == 0) {
+ if (p->ob_type != &PyInt_Type ||
+ p->ob_refcnt == 0) {
p->ob_type = (struct _typeobject *)
free_list;
free_list = p;
@@ -986,7 +1019,7 @@
for (i = 0, p = &list->objects[0];
i < N_INTOBJECTS;
i++, p++) {
- if (PyInt_Check(p) && p->ob_refcnt != 0)
+ if (p->ob_type == &PyInt_Type && p->ob_refcnt != 0)
fprintf(stderr,
"# <int at %p, refcnt=%d, val=%ld>\n",
p, p->ob_refcnt, p->ob_ival);