symbian-qemu-0.9.1-12/python-2.6.1/Objects/classobject.c
changeset 1 2fb8b9db1c86
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/symbian-qemu-0.9.1-12/python-2.6.1/Objects/classobject.c	Fri Jul 31 15:01:17 2009 +0100
@@ -0,0 +1,2673 @@
+
+/* Class object implementation */
+
+#include "Python.h"
+#include "structmember.h"
+
+/* Free list for method objects to safe malloc/free overhead
+ * The im_self element is used to chain the elements.
+ */
+static PyMethodObject *free_list;
+static int numfree = 0;
+#ifndef PyMethod_MAXFREELIST
+#define PyMethod_MAXFREELIST 256
+#endif
+
+#define TP_DESCR_GET(t) \
+    (PyType_HasFeature(t, Py_TPFLAGS_HAVE_CLASS) ? (t)->tp_descr_get : NULL)
+
+/* Forward */
+static PyObject *class_lookup(PyClassObject *, PyObject *,
+			      PyClassObject **);
+static PyObject *instance_getattr1(PyInstanceObject *, PyObject *);
+static PyObject *instance_getattr2(PyInstanceObject *, PyObject *);
+
+static PyObject *getattrstr, *setattrstr, *delattrstr;
+
+
+PyObject *
+PyClass_New(PyObject *bases, PyObject *dict, PyObject *name)
+     /* bases is NULL or tuple of classobjects! */
+{
+	PyClassObject *op, *dummy;
+	static PyObject *docstr, *modstr, *namestr;
+	if (docstr == NULL) {
+		docstr= PyString_InternFromString("__doc__");
+		if (docstr == NULL)
+			return NULL;
+	}
+	if (modstr == NULL) {
+		modstr= PyString_InternFromString("__module__");
+		if (modstr == NULL)
+			return NULL;
+	}
+	if (namestr == NULL) {
+		namestr= PyString_InternFromString("__name__");
+		if (namestr == NULL)
+			return NULL;
+	}
+	if (name == NULL || !PyString_Check(name)) {
+		PyErr_SetString(PyExc_TypeError,
+				"PyClass_New: name must be a string");
+		return NULL;
+	}
+	if (dict == NULL || !PyDict_Check(dict)) {
+		PyErr_SetString(PyExc_TypeError,
+				"PyClass_New: dict must be a dictionary");
+		return NULL;
+	}
+	if (PyDict_GetItem(dict, docstr) == NULL) {
+		if (PyDict_SetItem(dict, docstr, Py_None) < 0)
+			return NULL;
+	}
+	if (PyDict_GetItem(dict, modstr) == NULL) {
+		PyObject *globals = PyEval_GetGlobals();
+		if (globals != NULL) {
+			PyObject *modname = PyDict_GetItem(globals, namestr);
+			if (modname != NULL) {
+				if (PyDict_SetItem(dict, modstr, modname) < 0)
+					return NULL;
+			}
+		}
+	}
+	if (bases == NULL) {
+		bases = PyTuple_New(0);
+		if (bases == NULL)
+			return NULL;
+	}
+	else {
+		Py_ssize_t i, n;
+		PyObject *base;
+		if (!PyTuple_Check(bases)) {
+			PyErr_SetString(PyExc_TypeError,
+					"PyClass_New: bases must be a tuple");
+			return NULL;
+		}
+		n = PyTuple_Size(bases);
+		for (i = 0; i < n; i++) {
+			base = PyTuple_GET_ITEM(bases, i);
+			if (!PyClass_Check(base)) {
+				if (PyCallable_Check(
+					(PyObject *) base->ob_type))
+					return PyObject_CallFunctionObjArgs(
+						(PyObject *) base->ob_type,
+						name, bases, dict, NULL);
+				PyErr_SetString(PyExc_TypeError,
+					"PyClass_New: base must be a class");
+				return NULL;
+			}
+		}
+		Py_INCREF(bases);
+	}
+
+	if (getattrstr == NULL) {
+		getattrstr = PyString_InternFromString("__getattr__");
+		if (getattrstr == NULL)
+			goto alloc_error;
+		setattrstr = PyString_InternFromString("__setattr__");
+		if (setattrstr == NULL)
+			goto alloc_error;
+		delattrstr = PyString_InternFromString("__delattr__");
+		if (delattrstr == NULL)
+			goto alloc_error;
+	}
+
+	op = PyObject_GC_New(PyClassObject, &PyClass_Type);
+	if (op == NULL) {
+alloc_error:
+		Py_DECREF(bases);
+		return NULL;
+	}
+	op->cl_bases = bases;
+	Py_INCREF(dict);
+	op->cl_dict = dict;
+	Py_XINCREF(name);
+	op->cl_name = name;
+
+	op->cl_getattr = class_lookup(op, getattrstr, &dummy);
+	op->cl_setattr = class_lookup(op, setattrstr, &dummy);
+	op->cl_delattr = class_lookup(op, delattrstr, &dummy);
+	Py_XINCREF(op->cl_getattr);
+	Py_XINCREF(op->cl_setattr);
+	Py_XINCREF(op->cl_delattr);
+	_PyObject_GC_TRACK(op);
+	return (PyObject *) op;
+}
+
+PyObject *
+PyMethod_Function(PyObject *im)
+{
+	if (!PyMethod_Check(im)) {
+		PyErr_BadInternalCall();
+		return NULL;
+	}
+	return ((PyMethodObject *)im)->im_func;
+}
+
+PyObject *
+PyMethod_Self(PyObject *im)
+{
+	if (!PyMethod_Check(im)) {
+		PyErr_BadInternalCall();
+		return NULL;
+	}
+	return ((PyMethodObject *)im)->im_self;
+}
+
+PyObject *
+PyMethod_Class(PyObject *im)
+{
+	if (!PyMethod_Check(im)) {
+		PyErr_BadInternalCall();
+		return NULL;
+	}
+	return ((PyMethodObject *)im)->im_class;
+}
+
+PyDoc_STRVAR(class_doc,
+"classobj(name, bases, dict)\n\
+\n\
+Create a class object.  The name must be a string; the second argument\n\
+a tuple of classes, and the third a dictionary.");
+
+static PyObject *
+class_new(PyTypeObject *type, PyObject *args, PyObject *kwds)
+{
+	PyObject *name, *bases, *dict;
+	static char *kwlist[] = {"name", "bases", "dict", 0};
+
+	if (!PyArg_ParseTupleAndKeywords(args, kwds, "SOO", kwlist,
+					 &name, &bases, &dict))
+		return NULL;
+	return PyClass_New(bases, dict, name);
+}
+
+/* Class methods */
+
+static void
+class_dealloc(PyClassObject *op)
+{
+	_PyObject_GC_UNTRACK(op);
+	Py_DECREF(op->cl_bases);
+	Py_DECREF(op->cl_dict);
+	Py_XDECREF(op->cl_name);
+	Py_XDECREF(op->cl_getattr);
+	Py_XDECREF(op->cl_setattr);
+	Py_XDECREF(op->cl_delattr);
+	PyObject_GC_Del(op);
+}
+
+static PyObject *
+class_lookup(PyClassObject *cp, PyObject *name, PyClassObject **pclass)
+{
+	Py_ssize_t i, n;
+	PyObject *value = PyDict_GetItem(cp->cl_dict, name);
+	if (value != NULL) {
+		*pclass = cp;
+		return value;
+	}
+	n = PyTuple_Size(cp->cl_bases);
+	for (i = 0; i < n; i++) {
+		/* XXX What if one of the bases is not a class? */
+		PyObject *v = class_lookup(
+			(PyClassObject *)
+			PyTuple_GetItem(cp->cl_bases, i), name, pclass);
+		if (v != NULL)
+			return v;
+	}
+	return NULL;
+}
+
+static PyObject *
+class_getattr(register PyClassObject *op, PyObject *name)
+{
+	register PyObject *v;
+	register char *sname = PyString_AsString(name);
+	PyClassObject *klass;
+	descrgetfunc f;
+
+	if (sname[0] == '_' && sname[1] == '_') {
+		if (strcmp(sname, "__dict__") == 0) {
+			if (PyEval_GetRestricted()) {
+				PyErr_SetString(PyExc_RuntimeError,
+			   "class.__dict__ not accessible in restricted mode");
+				return NULL;
+			}
+			Py_INCREF(op->cl_dict);
+			return op->cl_dict;
+		}
+		if (strcmp(sname, "__bases__") == 0) {
+			Py_INCREF(op->cl_bases);
+			return op->cl_bases;
+		}
+		if (strcmp(sname, "__name__") == 0) {
+			if (op->cl_name == NULL)
+				v = Py_None;
+			else
+				v = op->cl_name;
+			Py_INCREF(v);
+			return v;
+		}
+	}
+	v = class_lookup(op, name, &klass);
+	if (v == NULL) {
+		PyErr_Format(PyExc_AttributeError,
+			     "class %.50s has no attribute '%.400s'",
+			     PyString_AS_STRING(op->cl_name), sname);
+		return NULL;
+	}
+	f = TP_DESCR_GET(v->ob_type);
+	if (f == NULL)
+		Py_INCREF(v);
+	else
+		v = f(v, (PyObject *)NULL, (PyObject *)op);
+	return v;
+}
+
+static void
+set_slot(PyObject **slot, PyObject *v)
+{
+	PyObject *temp = *slot;
+	Py_XINCREF(v);
+	*slot = v;
+	Py_XDECREF(temp);
+}
+
+static void
+set_attr_slots(PyClassObject *c)
+{
+	PyClassObject *dummy;
+
+	set_slot(&c->cl_getattr, class_lookup(c, getattrstr, &dummy));
+	set_slot(&c->cl_setattr, class_lookup(c, setattrstr, &dummy));
+	set_slot(&c->cl_delattr, class_lookup(c, delattrstr, &dummy));
+}
+
+static char *
+set_dict(PyClassObject *c, PyObject *v)
+{
+	if (v == NULL || !PyDict_Check(v))
+		return "__dict__ must be a dictionary object";
+	set_slot(&c->cl_dict, v);
+	set_attr_slots(c);
+	return "";
+}
+
+static char *
+set_bases(PyClassObject *c, PyObject *v)
+{
+	Py_ssize_t i, n;
+
+	if (v == NULL || !PyTuple_Check(v))
+		return "__bases__ must be a tuple object";
+	n = PyTuple_Size(v);
+	for (i = 0; i < n; i++) {
+		PyObject *x = PyTuple_GET_ITEM(v, i);
+		if (!PyClass_Check(x))
+			return "__bases__ items must be classes";
+		if (PyClass_IsSubclass(x, (PyObject *)c))
+			return "a __bases__ item causes an inheritance cycle";
+	}
+	set_slot(&c->cl_bases, v);
+	set_attr_slots(c);
+	return "";
+}
+
+static char *
+set_name(PyClassObject *c, PyObject *v)
+{
+	if (v == NULL || !PyString_Check(v))
+		return "__name__ must be a string object";
+	if (strlen(PyString_AS_STRING(v)) != (size_t)PyString_GET_SIZE(v))
+		return "__name__ must not contain null bytes";
+	set_slot(&c->cl_name, v);
+	return "";
+}
+
+static int
+class_setattr(PyClassObject *op, PyObject *name, PyObject *v)
+{
+	char *sname;
+	if (PyEval_GetRestricted()) {
+		PyErr_SetString(PyExc_RuntimeError,
+			   "classes are read-only in restricted mode");
+		return -1;
+	}
+	sname = PyString_AsString(name);
+	if (sname[0] == '_' && sname[1] == '_') {
+		Py_ssize_t n = PyString_Size(name);
+		if (sname[n-1] == '_' && sname[n-2] == '_') {
+			char *err = NULL;
+			if (strcmp(sname, "__dict__") == 0)
+				err = set_dict(op, v);
+			else if (strcmp(sname, "__bases__") == 0)
+				err = set_bases(op, v);
+			else if (strcmp(sname, "__name__") == 0)
+				err = set_name(op, v);
+			else if (strcmp(sname, "__getattr__") == 0)
+				set_slot(&op->cl_getattr, v);
+			else if (strcmp(sname, "__setattr__") == 0)
+				set_slot(&op->cl_setattr, v);
+			else if (strcmp(sname, "__delattr__") == 0)
+				set_slot(&op->cl_delattr, v);
+			/* For the last three, we fall through to update the
+			   dictionary as well. */
+			if (err != NULL) {
+				if (*err == '\0')
+					return 0;
+				PyErr_SetString(PyExc_TypeError, err);
+				return -1;
+			}
+		}
+	}
+	if (v == NULL) {
+		int rv = PyDict_DelItem(op->cl_dict, name);
+		if (rv < 0)
+			PyErr_Format(PyExc_AttributeError,
+				     "class %.50s has no attribute '%.400s'",
+				     PyString_AS_STRING(op->cl_name), sname);
+		return rv;
+	}
+	else
+		return PyDict_SetItem(op->cl_dict, name, v);
+}
+
+static PyObject *
+class_repr(PyClassObject *op)
+{
+	PyObject *mod = PyDict_GetItemString(op->cl_dict, "__module__");
+	char *name;
+	if (op->cl_name == NULL || !PyString_Check(op->cl_name))
+		name = "?";
+	else
+		name = PyString_AsString(op->cl_name);
+	if (mod == NULL || !PyString_Check(mod))
+		return PyString_FromFormat("<class ?.%s at %p>", name, op);
+	else
+		return PyString_FromFormat("<class %s.%s at %p>",
+					   PyString_AsString(mod),
+					   name, op);
+}
+
+static PyObject *
+class_str(PyClassObject *op)
+{
+	PyObject *mod = PyDict_GetItemString(op->cl_dict, "__module__");
+	PyObject *name = op->cl_name;
+	PyObject *res;
+	Py_ssize_t m, n;
+
+	if (name == NULL || !PyString_Check(name))
+		return class_repr(op);
+	if (mod == NULL || !PyString_Check(mod)) {
+		Py_INCREF(name);
+		return name;
+	}
+	m = PyString_GET_SIZE(mod);
+	n = PyString_GET_SIZE(name);
+	res = PyString_FromStringAndSize((char *)NULL, m+1+n);
+	if (res != NULL) {
+		char *s = PyString_AS_STRING(res);
+		memcpy(s, PyString_AS_STRING(mod), m);
+		s += m;
+		*s++ = '.';
+		memcpy(s, PyString_AS_STRING(name), n);
+	}
+	return res;
+}
+
+static int
+class_traverse(PyClassObject *o, visitproc visit, void *arg)
+{
+	Py_VISIT(o->cl_bases);
+	Py_VISIT(o->cl_dict);
+	Py_VISIT(o->cl_name);
+	Py_VISIT(o->cl_getattr);
+	Py_VISIT(o->cl_setattr);
+	Py_VISIT(o->cl_delattr);
+	return 0;
+}
+
+PyTypeObject PyClass_Type = {
+	PyObject_HEAD_INIT(&PyType_Type)
+	0,
+	"classobj",
+	sizeof(PyClassObject),
+	0,
+	(destructor)class_dealloc,		/* tp_dealloc */
+	0,					/* tp_print */
+	0,					/* tp_getattr */
+	0,					/* tp_setattr */
+	0,					/* tp_compare */
+	(reprfunc)class_repr,			/* tp_repr */
+	0,					/* tp_as_number */
+	0,					/* tp_as_sequence */
+	0,					/* tp_as_mapping */
+	0,					/* tp_hash */
+	PyInstance_New,				/* tp_call */
+	(reprfunc)class_str,			/* tp_str */
+	(getattrofunc)class_getattr,		/* tp_getattro */
+	(setattrofunc)class_setattr,		/* tp_setattro */
+	0,					/* tp_as_buffer */
+	Py_TPFLAGS_DEFAULT | Py_TPFLAGS_HAVE_GC,/* tp_flags */
+	class_doc,				/* tp_doc */
+	(traverseproc)class_traverse,		/* 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 */
+	0,					/* tp_descr_get */
+	0,					/* tp_descr_set */
+	0,					/* tp_dictoffset */
+	0,					/* tp_init */
+	0,					/* tp_alloc */
+	class_new,				/* tp_new */
+};
+
+int
+PyClass_IsSubclass(PyObject *klass, PyObject *base)
+{
+	Py_ssize_t i, n;
+	PyClassObject *cp;
+	if (klass == base)
+		return 1;
+	if (PyTuple_Check(base)) {
+		n = PyTuple_GET_SIZE(base);
+		for (i = 0; i < n; i++) {
+			if (PyClass_IsSubclass(klass, PyTuple_GET_ITEM(base, i)))
+				return 1;
+		}
+		return 0;
+	}
+	if (klass == NULL || !PyClass_Check(klass))
+		return 0;
+	cp = (PyClassObject *)klass;
+	n = PyTuple_Size(cp->cl_bases);
+	for (i = 0; i < n; i++) {
+		if (PyClass_IsSubclass(PyTuple_GetItem(cp->cl_bases, i), base))
+			return 1;
+	}
+	return 0;
+}
+
+
+/* Instance objects */
+
+PyObject *
+PyInstance_NewRaw(PyObject *klass, PyObject *dict)
+{
+	PyInstanceObject *inst;
+
+	if (!PyClass_Check(klass)) {
+		PyErr_BadInternalCall();
+		return NULL;
+	}
+	if (dict == NULL) {
+		dict = PyDict_New();
+		if (dict == NULL)
+			return NULL;
+	}
+	else {
+		if (!PyDict_Check(dict)) {
+			PyErr_BadInternalCall();
+			return NULL;
+		}
+		Py_INCREF(dict);
+	}
+	inst = PyObject_GC_New(PyInstanceObject, &PyInstance_Type);
+	if (inst == NULL) {
+		Py_DECREF(dict);
+		return NULL;
+	}
+	inst->in_weakreflist = NULL;
+	Py_INCREF(klass);
+	inst->in_class = (PyClassObject *)klass;
+	inst->in_dict = dict;
+	_PyObject_GC_TRACK(inst);
+	return (PyObject *)inst;
+}
+
+PyObject *
+PyInstance_New(PyObject *klass, PyObject *arg, PyObject *kw)
+{
+	register PyInstanceObject *inst;
+	PyObject *init;
+	static PyObject *initstr;
+
+	if (initstr == NULL) {
+		initstr = PyString_InternFromString("__init__");
+		if (initstr == NULL)
+			return NULL;
+	}
+	inst = (PyInstanceObject *) PyInstance_NewRaw(klass, NULL);
+	if (inst == NULL)
+		return NULL;
+	init = instance_getattr2(inst, initstr);
+	if (init == NULL) {
+		if (PyErr_Occurred()) {
+			Py_DECREF(inst);
+			return NULL;
+		}
+		if ((arg != NULL && (!PyTuple_Check(arg) ||
+				     PyTuple_Size(arg) != 0))
+		    || (kw != NULL && (!PyDict_Check(kw) ||
+				      PyDict_Size(kw) != 0))) {
+			PyErr_SetString(PyExc_TypeError,
+				   "this constructor takes no arguments");
+			Py_DECREF(inst);
+			inst = NULL;
+		}
+	}
+	else {
+		PyObject *res = PyEval_CallObjectWithKeywords(init, arg, kw);
+		Py_DECREF(init);
+		if (res == NULL) {
+			Py_DECREF(inst);
+			inst = NULL;
+		}
+		else {
+			if (res != Py_None) {
+				PyErr_SetString(PyExc_TypeError,
+					   "__init__() should return None");
+				Py_DECREF(inst);
+				inst = NULL;
+			}
+			Py_DECREF(res);
+		}
+	}
+	return (PyObject *)inst;
+}
+
+/* Instance methods */
+
+PyDoc_STRVAR(instance_doc,
+"instance(class[, dict])\n\
+\n\
+Create an instance without calling its __init__() method.\n\
+The class must be a classic class.\n\
+If present, dict must be a dictionary or None.");
+
+static PyObject *
+instance_new(PyTypeObject* type, PyObject* args, PyObject *kw)
+{
+	PyObject *klass;
+	PyObject *dict = Py_None;
+
+	if (!PyArg_ParseTuple(args, "O!|O:instance",
+			      &PyClass_Type, &klass, &dict))
+		return NULL;
+
+	if (dict == Py_None)
+		dict = NULL;
+	else if (!PyDict_Check(dict)) {
+		PyErr_SetString(PyExc_TypeError,
+		      "instance() second arg must be dictionary or None");
+		return NULL;
+	}
+	return PyInstance_NewRaw(klass, dict);
+}
+
+
+static void
+instance_dealloc(register PyInstanceObject *inst)
+{
+	PyObject *error_type, *error_value, *error_traceback;
+	PyObject *del;
+	static PyObject *delstr;
+
+	_PyObject_GC_UNTRACK(inst);
+	if (inst->in_weakreflist != NULL)
+		PyObject_ClearWeakRefs((PyObject *) inst);
+
+	/* Temporarily resurrect the object. */
+	assert(inst->ob_type == &PyInstance_Type);
+	assert(inst->ob_refcnt == 0);
+	inst->ob_refcnt = 1;
+
+	/* Save the current exception, if any. */
+	PyErr_Fetch(&error_type, &error_value, &error_traceback);
+	/* Execute __del__ method, if any. */
+	if (delstr == NULL) {
+		delstr = PyString_InternFromString("__del__");
+		if (delstr == NULL)
+			PyErr_WriteUnraisable((PyObject*)inst);
+	}
+	if (delstr && (del = instance_getattr2(inst, delstr)) != NULL) {
+		PyObject *res = PyEval_CallObject(del, (PyObject *)NULL);
+		if (res == NULL)
+			PyErr_WriteUnraisable(del);
+		else
+			Py_DECREF(res);
+		Py_DECREF(del);
+	}
+	/* Restore the saved exception. */
+	PyErr_Restore(error_type, error_value, error_traceback);
+
+	/* Undo the temporary resurrection; can't use DECREF here, it would
+	 * cause a recursive call.
+	 */
+	assert(inst->ob_refcnt > 0);
+	if (--inst->ob_refcnt == 0) {
+
+		/* New weakrefs could be created during the finalizer call.
+		    If this occurs, clear them out without calling their
+		    finalizers since they might rely on part of the object
+		    being finalized that has already been destroyed. */
+		while (inst->in_weakreflist != NULL) {
+			_PyWeakref_ClearRef((PyWeakReference *)
+                                            (inst->in_weakreflist));
+		}
+
+		Py_DECREF(inst->in_class);
+		Py_XDECREF(inst->in_dict);
+		PyObject_GC_Del(inst);
+	}
+	else {
+		Py_ssize_t refcnt = inst->ob_refcnt;
+		/* __del__ resurrected it!  Make it look like the original
+		 * Py_DECREF never happened.
+		 */
+		_Py_NewReference((PyObject *)inst);
+		inst->ob_refcnt = refcnt;
+		_PyObject_GC_TRACK(inst);
+		/* If Py_REF_DEBUG, _Py_NewReference bumped _Py_RefTotal, so
+		 * we need to undo that. */
+		_Py_DEC_REFTOTAL;
+		/* If Py_TRACE_REFS, _Py_NewReference re-added self to the
+		 * object chain, so no more to do there.
+		 * If COUNT_ALLOCS, the original decref bumped tp_frees, and
+		 * _Py_NewReference bumped tp_allocs: both of those need to be
+		 * undone.
+		 */
+#ifdef COUNT_ALLOCS
+		--inst->ob_type->tp_frees;
+		--inst->ob_type->tp_allocs;
+#endif
+	}
+}
+
+static PyObject *
+instance_getattr1(register PyInstanceObject *inst, PyObject *name)
+{
+	register PyObject *v;
+	register char *sname = PyString_AsString(name);
+	if (sname[0] == '_' && sname[1] == '_') {
+		if (strcmp(sname, "__dict__") == 0) {
+			if (PyEval_GetRestricted()) {
+				PyErr_SetString(PyExc_RuntimeError,
+			"instance.__dict__ not accessible in restricted mode");
+				return NULL;
+			}
+			Py_INCREF(inst->in_dict);
+			return inst->in_dict;
+		}
+		if (strcmp(sname, "__class__") == 0) {
+			Py_INCREF(inst->in_class);
+			return (PyObject *)inst->in_class;
+		}
+	}
+	v = instance_getattr2(inst, name);
+	if (v == NULL && !PyErr_Occurred()) {
+		PyErr_Format(PyExc_AttributeError,
+			     "%.50s instance has no attribute '%.400s'",
+			     PyString_AS_STRING(inst->in_class->cl_name), sname);
+	}
+	return v;
+}
+
+static PyObject *
+instance_getattr2(register PyInstanceObject *inst, PyObject *name)
+{
+	register PyObject *v;
+	PyClassObject *klass;
+	descrgetfunc f;
+
+	v = PyDict_GetItem(inst->in_dict, name);
+	if (v != NULL) {
+		Py_INCREF(v);
+		return v;
+	}
+	v = class_lookup(inst->in_class, name, &klass);
+	if (v != NULL) {
+		Py_INCREF(v);
+		f = TP_DESCR_GET(v->ob_type);
+		if (f != NULL) {
+			PyObject *w = f(v, (PyObject *)inst,
+					(PyObject *)(inst->in_class));
+			Py_DECREF(v);
+			v = w;
+		}
+	}
+	return v;
+}
+
+static PyObject *
+instance_getattr(register PyInstanceObject *inst, PyObject *name)
+{
+	register PyObject *func, *res;
+	res = instance_getattr1(inst, name);
+	if (res == NULL && (func = inst->in_class->cl_getattr) != NULL) {
+		PyObject *args;
+		if (!PyErr_ExceptionMatches(PyExc_AttributeError))
+			return NULL;
+		PyErr_Clear();
+		args = PyTuple_Pack(2, inst, name);
+		if (args == NULL)
+			return NULL;
+		res = PyEval_CallObject(func, args);
+		Py_DECREF(args);
+	}
+	return res;
+}
+
+/* See classobject.h comments:  this only does dict lookups, and is always
+ * safe to call.
+ */
+PyObject *
+_PyInstance_Lookup(PyObject *pinst, PyObject *name)
+{
+	PyObject *v;
+	PyClassObject *klass;
+	PyInstanceObject *inst;	/* pinst cast to the right type */
+
+	assert(PyInstance_Check(pinst));
+	inst = (PyInstanceObject *)pinst;
+
+	assert(PyString_Check(name));
+
+ 	v = PyDict_GetItem(inst->in_dict, name);
+	if (v == NULL)
+		v = class_lookup(inst->in_class, name, &klass);
+	return v;
+}
+
+static int
+instance_setattr1(PyInstanceObject *inst, PyObject *name, PyObject *v)
+{
+	if (v == NULL) {
+		int rv = PyDict_DelItem(inst->in_dict, name);
+		if (rv < 0)
+			PyErr_Format(PyExc_AttributeError,
+				     "%.50s instance has no attribute '%.400s'",
+				     PyString_AS_STRING(inst->in_class->cl_name),
+				     PyString_AS_STRING(name));
+		return rv;
+	}
+	else
+		return PyDict_SetItem(inst->in_dict, name, v);
+}
+
+static int
+instance_setattr(PyInstanceObject *inst, PyObject *name, PyObject *v)
+{
+	PyObject *func, *args, *res, *tmp;
+	char *sname = PyString_AsString(name);
+	if (sname[0] == '_' && sname[1] == '_') {
+		Py_ssize_t n = PyString_Size(name);
+		if (sname[n-1] == '_' && sname[n-2] == '_') {
+			if (strcmp(sname, "__dict__") == 0) {
+				if (PyEval_GetRestricted()) {
+					PyErr_SetString(PyExc_RuntimeError,
+				 "__dict__ not accessible in restricted mode");
+					return -1;
+				}
+				if (v == NULL || !PyDict_Check(v)) {
+				    PyErr_SetString(PyExc_TypeError,
+				       "__dict__ must be set to a dictionary");
+				    return -1;
+				}
+				tmp = inst->in_dict;
+				Py_INCREF(v);
+				inst->in_dict = v;
+				Py_DECREF(tmp);
+				return 0;
+			}
+			if (strcmp(sname, "__class__") == 0) {
+				if (PyEval_GetRestricted()) {
+					PyErr_SetString(PyExc_RuntimeError,
+				"__class__ not accessible in restricted mode");
+					return -1;
+				}
+				if (v == NULL || !PyClass_Check(v)) {
+					PyErr_SetString(PyExc_TypeError,
+					   "__class__ must be set to a class");
+					return -1;
+				}
+				tmp = (PyObject *)(inst->in_class);
+				Py_INCREF(v);
+				inst->in_class = (PyClassObject *)v;
+				Py_DECREF(tmp);
+				return 0;
+			}
+		}
+	}
+	if (v == NULL)
+		func = inst->in_class->cl_delattr;
+	else
+		func = inst->in_class->cl_setattr;
+	if (func == NULL)
+		return instance_setattr1(inst, name, v);
+	if (v == NULL)
+		args = PyTuple_Pack(2, inst, name);
+	else
+		args = PyTuple_Pack(3, inst, name, v);
+	if (args == NULL)
+		return -1;
+	res = PyEval_CallObject(func, args);
+	Py_DECREF(args);
+	if (res == NULL)
+		return -1;
+	Py_DECREF(res);
+	return 0;
+}
+
+static PyObject *
+instance_repr(PyInstanceObject *inst)
+{
+	PyObject *func;
+	PyObject *res;
+	static PyObject *reprstr;
+
+	if (reprstr == NULL) {
+		reprstr = PyString_InternFromString("__repr__");
+		if (reprstr == NULL)
+			return NULL;
+	}
+	func = instance_getattr(inst, reprstr);
+	if (func == NULL) {
+		PyObject *classname, *mod;
+		char *cname;
+		if (!PyErr_ExceptionMatches(PyExc_AttributeError))
+			return NULL;
+		PyErr_Clear();
+		classname = inst->in_class->cl_name;
+		mod = PyDict_GetItemString(inst->in_class->cl_dict,
+					   "__module__");
+		if (classname != NULL && PyString_Check(classname))
+			cname = PyString_AsString(classname);
+		else
+			cname = "?";
+		if (mod == NULL || !PyString_Check(mod))
+			return PyString_FromFormat("<?.%s instance at %p>",
+						   cname, inst);
+		else
+			return PyString_FromFormat("<%s.%s instance at %p>",
+						   PyString_AsString(mod),
+						   cname, inst);
+	}
+	res = PyEval_CallObject(func, (PyObject *)NULL);
+	Py_DECREF(func);
+	return res;
+}
+
+static PyObject *
+instance_str(PyInstanceObject *inst)
+{
+	PyObject *func;
+	PyObject *res;
+	static PyObject *strstr;
+
+	if (strstr == NULL) {
+		strstr = PyString_InternFromString("__str__");
+		if (strstr == NULL)
+			return NULL;
+	}
+	func = instance_getattr(inst, strstr);
+	if (func == NULL) {
+		if (!PyErr_ExceptionMatches(PyExc_AttributeError))
+			return NULL;
+		PyErr_Clear();
+		return instance_repr(inst);
+	}
+	res = PyEval_CallObject(func, (PyObject *)NULL);
+	Py_DECREF(func);
+	return res;
+}
+
+static long
+instance_hash(PyInstanceObject *inst)
+{
+	PyObject *func;
+	PyObject *res;
+	long outcome;
+	static PyObject *hashstr, *eqstr, *cmpstr;
+
+	if (hashstr == NULL) {
+		hashstr = PyString_InternFromString("__hash__");
+		if (hashstr == NULL)
+			return -1;
+	}
+	func = instance_getattr(inst, hashstr);
+	if (func == NULL) {
+		if (!PyErr_ExceptionMatches(PyExc_AttributeError))
+			return -1;
+		PyErr_Clear();
+		/* If there is no __eq__ and no __cmp__ method, we hash on the
+		   address.  If an __eq__ or __cmp__ method exists, there must
+		   be a __hash__. */
+		if (eqstr == NULL) {
+			eqstr = PyString_InternFromString("__eq__");
+			if (eqstr == NULL)
+				return -1;
+		}
+		func = instance_getattr(inst, eqstr);
+		if (func == NULL) {
+			if (!PyErr_ExceptionMatches(PyExc_AttributeError))
+				return -1;
+			PyErr_Clear();
+			if (cmpstr == NULL) {
+				cmpstr = PyString_InternFromString("__cmp__");
+				if (cmpstr == NULL)
+					return -1;
+			}
+			func = instance_getattr(inst, cmpstr);
+			if (func == NULL) {
+				if (!PyErr_ExceptionMatches(
+					PyExc_AttributeError))
+					return -1;
+				PyErr_Clear();
+				return _Py_HashPointer(inst);
+			}
+		}
+		Py_XDECREF(func);
+		PyErr_SetString(PyExc_TypeError, "unhashable instance");
+		return -1;
+	}
+	res = PyEval_CallObject(func, (PyObject *)NULL);
+	Py_DECREF(func);
+	if (res == NULL)
+		return -1;
+	if (PyInt_Check(res) || PyLong_Check(res))
+		/* This already converts a -1 result to -2. */
+		outcome = res->ob_type->tp_hash(res);
+	else {
+		PyErr_SetString(PyExc_TypeError,
+				"__hash__() should return an int");
+		outcome = -1;
+	}
+	Py_DECREF(res);
+	return outcome;
+}
+
+static int
+instance_traverse(PyInstanceObject *o, visitproc visit, void *arg)
+{
+	Py_VISIT(o->in_class);
+	Py_VISIT(o->in_dict);
+	return 0;
+}
+
+static PyObject *getitemstr, *setitemstr, *delitemstr, *lenstr;
+static PyObject *iterstr, *nextstr;
+
+static Py_ssize_t
+instance_length(PyInstanceObject *inst)
+{
+	PyObject *func;
+	PyObject *res;
+	Py_ssize_t outcome;
+
+	if (lenstr == NULL) {
+		lenstr = PyString_InternFromString("__len__");
+		if (lenstr == NULL)
+			return -1;
+	}
+	func = instance_getattr(inst, lenstr);
+	if (func == NULL)
+		return -1;
+	res = PyEval_CallObject(func, (PyObject *)NULL);
+	Py_DECREF(func);
+	if (res == NULL)
+		return -1;
+	if (PyInt_Check(res)) {
+		outcome = PyInt_AsSsize_t(res);
+		if (outcome == -1 && PyErr_Occurred()) {
+			Py_DECREF(res);
+			return -1;
+		}
+#if SIZEOF_SIZE_T < SIZEOF_INT
+		/* Overflow check -- range of PyInt is more than C int */
+		if (outcome != (int)outcome) {
+			PyErr_SetString(PyExc_OverflowError,
+			 "__len__() should return 0 <= outcome < 2**31");
+			outcome = -1;
+		}
+		else
+#endif
+		if (outcome < 0) {
+			PyErr_SetString(PyExc_ValueError,
+					"__len__() should return >= 0");
+			outcome = -1;
+		}
+	}
+	else {
+		PyErr_SetString(PyExc_TypeError,
+				"__len__() should return an int");
+		outcome = -1;
+	}
+	Py_DECREF(res);
+	return outcome;
+}
+
+static PyObject *
+instance_subscript(PyInstanceObject *inst, PyObject *key)
+{
+	PyObject *func;
+	PyObject *arg;
+	PyObject *res;
+
+	if (getitemstr == NULL) {
+		getitemstr = PyString_InternFromString("__getitem__");
+		if (getitemstr == NULL)
+			return NULL;
+	}
+	func = instance_getattr(inst, getitemstr);
+	if (func == NULL)
+		return NULL;
+	arg = PyTuple_Pack(1, key);
+	if (arg == NULL) {
+		Py_DECREF(func);
+		return NULL;
+	}
+	res = PyEval_CallObject(func, arg);
+	Py_DECREF(func);
+	Py_DECREF(arg);
+	return res;
+}
+
+static int
+instance_ass_subscript(PyInstanceObject *inst, PyObject *key, PyObject *value)
+{
+	PyObject *func;
+	PyObject *arg;
+	PyObject *res;
+
+	if (value == NULL) {
+		if (delitemstr == NULL) {
+			delitemstr = PyString_InternFromString("__delitem__");
+			if (delitemstr == NULL)
+				return -1;
+		}
+		func = instance_getattr(inst, delitemstr);
+	}
+	else {
+		if (setitemstr == NULL) {
+			setitemstr = PyString_InternFromString("__setitem__");
+			if (setitemstr == NULL)
+				return -1;
+		}
+		func = instance_getattr(inst, setitemstr);
+	}
+	if (func == NULL)
+		return -1;
+	if (value == NULL)
+		arg = PyTuple_Pack(1, key);
+	else
+		arg = PyTuple_Pack(2, key, value);
+	if (arg == NULL) {
+		Py_DECREF(func);
+		return -1;
+	}
+	res = PyEval_CallObject(func, arg);
+	Py_DECREF(func);
+	Py_DECREF(arg);
+	if (res == NULL)
+		return -1;
+	Py_DECREF(res);
+	return 0;
+}
+
+static PyMappingMethods instance_as_mapping = {
+	(lenfunc)instance_length,		/* mp_length */
+	(binaryfunc)instance_subscript,		/* mp_subscript */
+	(objobjargproc)instance_ass_subscript,	/* mp_ass_subscript */
+};
+
+static PyObject *
+instance_item(PyInstanceObject *inst, Py_ssize_t i)
+{
+	PyObject *func, *res;
+
+	if (getitemstr == NULL) {
+		getitemstr = PyString_InternFromString("__getitem__");
+		if (getitemstr == NULL)
+			return NULL;
+	}
+	func = instance_getattr(inst, getitemstr);
+	if (func == NULL)
+		return NULL;
+	res = PyObject_CallFunction(func, "n", i);
+	Py_DECREF(func);
+	return res;
+}
+
+static PyObject *
+instance_slice(PyInstanceObject *inst, Py_ssize_t i, Py_ssize_t j)
+{
+	PyObject *func, *arg, *res;
+	static PyObject *getslicestr;
+
+	if (getslicestr == NULL) {
+		getslicestr = PyString_InternFromString("__getslice__");
+		if (getslicestr == NULL)
+			return NULL;
+	}
+	func = instance_getattr(inst, getslicestr);
+
+	if (func == NULL) {
+		if (!PyErr_ExceptionMatches(PyExc_AttributeError))
+			return NULL;
+		PyErr_Clear();
+
+		if (getitemstr == NULL) {
+			getitemstr = PyString_InternFromString("__getitem__");
+			if (getitemstr == NULL)
+				return NULL;
+		}
+		func = instance_getattr(inst, getitemstr);
+		if (func == NULL)
+			return NULL;
+		arg = Py_BuildValue("(N)", _PySlice_FromIndices(i, j));
+	}
+	else {
+		if (PyErr_WarnPy3k("in 3.x, __getslice__ has been removed; "
+				   "use __getitem__", 1) < 0) {
+			Py_DECREF(func);
+			return NULL;
+		}
+		arg = Py_BuildValue("(nn)", i, j);
+	}
+
+	if (arg == NULL) {
+		Py_DECREF(func);
+		return NULL;
+	}
+	res = PyEval_CallObject(func, arg);
+	Py_DECREF(func);
+	Py_DECREF(arg);
+	return res;
+}
+
+static int
+instance_ass_item(PyInstanceObject *inst, Py_ssize_t i, PyObject *item)
+{
+	PyObject *func, *arg, *res;
+
+	if (item == NULL) {
+		if (delitemstr == NULL) {
+			delitemstr = PyString_InternFromString("__delitem__");
+			if (delitemstr == NULL)
+				return -1;
+		}
+		func = instance_getattr(inst, delitemstr);
+	}
+	else {
+		if (setitemstr == NULL) {
+			setitemstr = PyString_InternFromString("__setitem__");
+			if (setitemstr == NULL)
+				return -1;
+		}
+		func = instance_getattr(inst, setitemstr);
+	}
+	if (func == NULL)
+		return -1;
+	if (item == NULL)
+		arg = PyInt_FromSsize_t(i);
+	else
+		arg = Py_BuildValue("(nO)", i, item);
+	if (arg == NULL) {
+		Py_DECREF(func);
+		return -1;
+	}
+	res = PyEval_CallObject(func, arg);
+	Py_DECREF(func);
+	Py_DECREF(arg);
+	if (res == NULL)
+		return -1;
+	Py_DECREF(res);
+	return 0;
+}
+
+static int
+instance_ass_slice(PyInstanceObject *inst, Py_ssize_t i, Py_ssize_t j, PyObject *value)
+{
+	PyObject *func, *arg, *res;
+	static PyObject *setslicestr, *delslicestr;
+
+	if (value == NULL) {
+		if (delslicestr == NULL) {
+			delslicestr =
+				PyString_InternFromString("__delslice__");
+			if (delslicestr == NULL)
+				return -1;
+		}
+		func = instance_getattr(inst, delslicestr);
+		if (func == NULL) {
+			if (!PyErr_ExceptionMatches(PyExc_AttributeError))
+				return -1;
+			PyErr_Clear();
+			if (delitemstr == NULL) {
+				delitemstr =
+				    PyString_InternFromString("__delitem__");
+				if (delitemstr == NULL)
+					return -1;
+			}
+			func = instance_getattr(inst, delitemstr);
+			if (func == NULL)
+				return -1;
+
+			arg = Py_BuildValue("(N)",
+					    _PySlice_FromIndices(i, j));
+		}
+		else {
+			if (PyErr_WarnPy3k("in 3.x, __delslice__ has been "
+				            "removed; use __delitem__", 1) < 0) {
+				Py_DECREF(func);
+				return -1;
+			}
+			arg = Py_BuildValue("(nn)", i, j);
+		}
+	}
+	else {
+		if (setslicestr == NULL) {
+			setslicestr =
+				PyString_InternFromString("__setslice__");
+			if (setslicestr == NULL)
+				return -1;
+		}
+		func = instance_getattr(inst, setslicestr);
+		if (func == NULL) {
+			if (!PyErr_ExceptionMatches(PyExc_AttributeError))
+				return -1;
+			PyErr_Clear();
+			if (setitemstr == NULL) {
+				setitemstr =
+				    PyString_InternFromString("__setitem__");
+				if (setitemstr == NULL)
+					return -1;
+			}
+			func = instance_getattr(inst, setitemstr);
+			if (func == NULL)
+				return -1;
+
+			arg = Py_BuildValue("(NO)",
+					    _PySlice_FromIndices(i, j), value);
+		}
+		else {
+			if (PyErr_WarnPy3k("in 3.x, __setslice__ has been "
+					   "removed; use __setitem__", 1) < 0) {
+				Py_DECREF(func);
+				return -1;
+			}
+			arg = Py_BuildValue("(nnO)", i, j, value);
+		}
+	}
+	if (arg == NULL) {
+		Py_DECREF(func);
+		return -1;
+	}
+	res = PyEval_CallObject(func, arg);
+	Py_DECREF(func);
+	Py_DECREF(arg);
+	if (res == NULL)
+		return -1;
+	Py_DECREF(res);
+	return 0;
+}
+
+static int
+instance_contains(PyInstanceObject *inst, PyObject *member)
+{
+	static PyObject *__contains__;
+	PyObject *func;
+
+	/* Try __contains__ first.
+	 * If that can't be done, try iterator-based searching.
+	 */
+
+	if(__contains__ == NULL) {
+		__contains__ = PyString_InternFromString("__contains__");
+		if(__contains__ == NULL)
+			return -1;
+	}
+	func = instance_getattr(inst, __contains__);
+	if (func) {
+		PyObject *res;
+		int ret;
+		PyObject *arg = PyTuple_Pack(1, member);
+		if(arg == NULL) {
+			Py_DECREF(func);
+			return -1;
+		}
+		res = PyEval_CallObject(func, arg);
+		Py_DECREF(func);
+		Py_DECREF(arg);
+		if(res == NULL)
+			return -1;
+		ret = PyObject_IsTrue(res);
+		Py_DECREF(res);
+		return ret;
+	}
+
+	/* Couldn't find __contains__. */
+	if (PyErr_ExceptionMatches(PyExc_AttributeError)) {
+		Py_ssize_t rc;
+		/* Assume the failure was simply due to that there is no
+		 * __contains__ attribute, and try iterating instead.
+		 */
+		PyErr_Clear();
+		rc = _PySequence_IterSearch((PyObject *)inst, member,
+					    PY_ITERSEARCH_CONTAINS);
+		if (rc >= 0)
+			return rc > 0;
+	}
+	return -1;
+}
+
+static PySequenceMethods
+instance_as_sequence = {
+	(lenfunc)instance_length,		/* sq_length */
+	0,					/* sq_concat */
+	0,					/* sq_repeat */
+	(ssizeargfunc)instance_item,		/* sq_item */
+	(ssizessizeargfunc)instance_slice,	/* sq_slice */
+	(ssizeobjargproc)instance_ass_item,	/* sq_ass_item */
+	(ssizessizeobjargproc)instance_ass_slice,/* sq_ass_slice */
+	(objobjproc)instance_contains,		/* sq_contains */
+};
+
+static PyObject *
+generic_unary_op(PyInstanceObject *self, PyObject *methodname)
+{
+	PyObject *func, *res;
+
+	if ((func = instance_getattr(self, methodname)) == NULL)
+		return NULL;
+	res = PyEval_CallObject(func, (PyObject *)NULL);
+	Py_DECREF(func);
+	return res;
+}
+
+static PyObject *
+generic_binary_op(PyObject *v, PyObject *w, char *opname)
+{
+	PyObject *result;
+	PyObject *args;
+	PyObject *func = PyObject_GetAttrString(v, opname);
+	if (func == NULL) {
+		if (!PyErr_ExceptionMatches(PyExc_AttributeError))
+			return NULL;
+		PyErr_Clear();
+		Py_INCREF(Py_NotImplemented);
+		return Py_NotImplemented;
+	}
+	args = PyTuple_Pack(1, w);
+	if (args == NULL) {
+		Py_DECREF(func);
+		return NULL;
+	}
+	result = PyEval_CallObject(func, args);
+	Py_DECREF(args);
+	Py_DECREF(func);
+	return result;
+}
+
+
+static PyObject *coerce_obj;
+
+/* Try one half of a binary operator involving a class instance. */
+static PyObject *
+half_binop(PyObject *v, PyObject *w, char *opname, binaryfunc thisfunc,
+		int swapped)
+{
+	PyObject *args;
+	PyObject *coercefunc;
+	PyObject *coerced = NULL;
+	PyObject *v1;
+	PyObject *result;
+
+	if (!PyInstance_Check(v)) {
+		Py_INCREF(Py_NotImplemented);
+		return Py_NotImplemented;
+	}
+
+	if (coerce_obj == NULL) {
+		coerce_obj = PyString_InternFromString("__coerce__");
+		if (coerce_obj == NULL)
+			return NULL;
+	}
+	coercefunc = PyObject_GetAttr(v, coerce_obj);
+	if (coercefunc == NULL) {
+		if (!PyErr_ExceptionMatches(PyExc_AttributeError))
+			return NULL;
+		PyErr_Clear();
+		return generic_binary_op(v, w, opname);
+	}
+
+	args = PyTuple_Pack(1, w);
+	if (args == NULL) {
+		Py_DECREF(coercefunc);
+		return NULL;
+	}
+	coerced = PyEval_CallObject(coercefunc, args);
+	Py_DECREF(args);
+	Py_DECREF(coercefunc);
+	if (coerced == NULL) {
+		return NULL;
+	}
+	if (coerced == Py_None || coerced == Py_NotImplemented) {
+		Py_DECREF(coerced);
+		return generic_binary_op(v, w, opname);
+	}
+	if (!PyTuple_Check(coerced) || PyTuple_Size(coerced) != 2) {
+		Py_DECREF(coerced);
+		PyErr_SetString(PyExc_TypeError,
+				"coercion should return None or 2-tuple");
+		return NULL;
+	}
+	v1 = PyTuple_GetItem(coerced, 0);
+	w = PyTuple_GetItem(coerced, 1);
+	if (v1->ob_type == v->ob_type && PyInstance_Check(v)) {
+		/* prevent recursion if __coerce__ returns self as the first
+		 * argument */
+		result = generic_binary_op(v1, w, opname);
+	} else {
+		if (Py_EnterRecursiveCall(" after coercion"))
+		    return NULL;
+		if (swapped)
+			result = (thisfunc)(w, v1);
+		else
+			result = (thisfunc)(v1, w);
+		Py_LeaveRecursiveCall();
+	}
+	Py_DECREF(coerced);
+	return result;
+}
+
+/* Implement a binary operator involving at least one class instance. */
+static PyObject *
+do_binop(PyObject *v, PyObject *w, char *opname, char *ropname,
+                   binaryfunc thisfunc)
+{
+	PyObject *result = half_binop(v, w, opname, thisfunc, 0);
+	if (result == Py_NotImplemented) {
+		Py_DECREF(result);
+		result = half_binop(w, v, ropname, thisfunc, 1);
+	}
+	return result;
+}
+
+static PyObject *
+do_binop_inplace(PyObject *v, PyObject *w, char *iopname, char *opname,
+			char *ropname, binaryfunc thisfunc)
+{
+	PyObject *result = half_binop(v, w, iopname, thisfunc, 0);
+	if (result == Py_NotImplemented) {
+		Py_DECREF(result);
+		result = do_binop(v, w, opname, ropname, thisfunc);
+	}
+	return result;
+}
+
+static int
+instance_coerce(PyObject **pv, PyObject **pw)
+{
+	PyObject *v = *pv;
+	PyObject *w = *pw;
+	PyObject *coercefunc;
+	PyObject *args;
+	PyObject *coerced;
+
+	if (coerce_obj == NULL) {
+		coerce_obj = PyString_InternFromString("__coerce__");
+		if (coerce_obj == NULL)
+			return -1;
+	}
+	coercefunc = PyObject_GetAttr(v, coerce_obj);
+	if (coercefunc == NULL) {
+		/* No __coerce__ method */
+		if (!PyErr_ExceptionMatches(PyExc_AttributeError))
+			return -1;
+		PyErr_Clear();
+		return 1;
+	}
+	/* Has __coerce__ method: call it */
+	args = PyTuple_Pack(1, w);
+	if (args == NULL) {
+		return -1;
+	}
+	coerced = PyEval_CallObject(coercefunc, args);
+	Py_DECREF(args);
+	Py_DECREF(coercefunc);
+	if (coerced == NULL) {
+		/* __coerce__ call raised an exception */
+		return -1;
+	}
+	if (coerced == Py_None || coerced == Py_NotImplemented) {
+		/* __coerce__ says "I can't do it" */
+		Py_DECREF(coerced);
+		return 1;
+	}
+	if (!PyTuple_Check(coerced) || PyTuple_Size(coerced) != 2) {
+		/* __coerce__ return value is malformed */
+		Py_DECREF(coerced);
+		PyErr_SetString(PyExc_TypeError,
+			   "coercion should return None or 2-tuple");
+		return -1;
+	}
+	/* __coerce__ returned two new values */
+	*pv = PyTuple_GetItem(coerced, 0);
+	*pw = PyTuple_GetItem(coerced, 1);
+	Py_INCREF(*pv);
+	Py_INCREF(*pw);
+	Py_DECREF(coerced);
+	return 0;
+}
+
+#define UNARY(funcname, methodname) \
+static PyObject *funcname(PyInstanceObject *self) { \
+	static PyObject *o; \
+	if (o == NULL) { o = PyString_InternFromString(methodname); \
+			 if (o == NULL) return NULL; } \
+	return generic_unary_op(self, o); \
+}
+
+/* unary function with a fallback */
+#define UNARY_FB(funcname, methodname, funcname_fb) \
+static PyObject *funcname(PyInstanceObject *self) { \
+	static PyObject *o; \
+	if (o == NULL) { o = PyString_InternFromString(methodname); \
+			 if (o == NULL) return NULL; } \
+	if (PyObject_HasAttr((PyObject*)self, o)) \
+		return generic_unary_op(self, o); \
+	else \
+		return funcname_fb(self); \
+}
+
+#define BINARY(f, m, n) \
+static PyObject *f(PyObject *v, PyObject *w) { \
+	return do_binop(v, w, "__" m "__", "__r" m "__", n); \
+}
+
+#define BINARY_INPLACE(f, m, n) \
+static PyObject *f(PyObject *v, PyObject *w) { \
+	return do_binop_inplace(v, w, "__i" m "__", "__" m "__", \
+			"__r" m "__", n); \
+}
+
+UNARY(instance_neg, "__neg__")
+UNARY(instance_pos, "__pos__")
+UNARY(instance_abs, "__abs__")
+
+BINARY(instance_or, "or", PyNumber_Or)
+BINARY(instance_and, "and", PyNumber_And)
+BINARY(instance_xor, "xor", PyNumber_Xor)
+BINARY(instance_lshift, "lshift", PyNumber_Lshift)
+BINARY(instance_rshift, "rshift", PyNumber_Rshift)
+BINARY(instance_add, "add", PyNumber_Add)
+BINARY(instance_sub, "sub", PyNumber_Subtract)
+BINARY(instance_mul, "mul", PyNumber_Multiply)
+BINARY(instance_div, "div", PyNumber_Divide)
+BINARY(instance_mod, "mod", PyNumber_Remainder)
+BINARY(instance_divmod, "divmod", PyNumber_Divmod)
+BINARY(instance_floordiv, "floordiv", PyNumber_FloorDivide)
+BINARY(instance_truediv, "truediv", PyNumber_TrueDivide)
+
+BINARY_INPLACE(instance_ior, "or", PyNumber_InPlaceOr)
+BINARY_INPLACE(instance_ixor, "xor", PyNumber_InPlaceXor)
+BINARY_INPLACE(instance_iand, "and", PyNumber_InPlaceAnd)
+BINARY_INPLACE(instance_ilshift, "lshift", PyNumber_InPlaceLshift)
+BINARY_INPLACE(instance_irshift, "rshift", PyNumber_InPlaceRshift)
+BINARY_INPLACE(instance_iadd, "add", PyNumber_InPlaceAdd)
+BINARY_INPLACE(instance_isub, "sub", PyNumber_InPlaceSubtract)
+BINARY_INPLACE(instance_imul, "mul", PyNumber_InPlaceMultiply)
+BINARY_INPLACE(instance_idiv, "div", PyNumber_InPlaceDivide)
+BINARY_INPLACE(instance_imod, "mod", PyNumber_InPlaceRemainder)
+BINARY_INPLACE(instance_ifloordiv, "floordiv", PyNumber_InPlaceFloorDivide)
+BINARY_INPLACE(instance_itruediv, "truediv", PyNumber_InPlaceTrueDivide)
+
+/* Try a 3-way comparison, returning an int; v is an instance.  Return:
+   -2 for an exception;
+   -1 if v < w;
+   0 if v == w;
+   1 if v > w;
+   2 if this particular 3-way comparison is not implemented or undefined.
+*/
+static int
+half_cmp(PyObject *v, PyObject *w)
+{
+	static PyObject *cmp_obj;
+	PyObject *args;
+	PyObject *cmp_func;
+	PyObject *result;
+	long l;
+
+	assert(PyInstance_Check(v));
+
+	if (cmp_obj == NULL) {
+		cmp_obj = PyString_InternFromString("__cmp__");
+		if (cmp_obj == NULL)
+			return -2;
+	}
+
+	cmp_func = PyObject_GetAttr(v, cmp_obj);
+	if (cmp_func == NULL) {
+		if (!PyErr_ExceptionMatches(PyExc_AttributeError))
+			return -2;
+		PyErr_Clear();
+		return 2;
+	}
+
+	args = PyTuple_Pack(1, w);
+	if (args == NULL) {
+		Py_DECREF(cmp_func);
+		return -2;
+	}
+
+	result = PyEval_CallObject(cmp_func, args);
+	Py_DECREF(args);
+	Py_DECREF(cmp_func);
+
+	if (result == NULL)
+		return -2;
+
+	if (result == Py_NotImplemented) {
+		Py_DECREF(result);
+		return 2;
+	}
+
+	l = PyInt_AsLong(result);
+	Py_DECREF(result);
+	if (l == -1 && PyErr_Occurred()) {
+		PyErr_SetString(PyExc_TypeError,
+			     "comparison did not return an int");
+		return -2;
+	}
+
+	return l < 0 ? -1 : l > 0 ? 1 : 0;
+}
+
+/* Try a 3-way comparison, returning an int; either v or w is an instance.
+   We first try a coercion.  Return:
+   -2 for an exception;
+   -1 if v < w;
+   0 if v == w;
+   1 if v > w;
+   2 if this particular 3-way comparison is not implemented or undefined.
+   THIS IS ONLY CALLED FROM object.c!
+*/
+static int
+instance_compare(PyObject *v, PyObject *w)
+{
+	int c;
+
+	c = PyNumber_CoerceEx(&v, &w);
+	if (c < 0)
+		return -2;
+	if (c == 0) {
+		/* If neither is now an instance, use regular comparison */
+		if (!PyInstance_Check(v) && !PyInstance_Check(w)) {
+			c = PyObject_Compare(v, w);
+			Py_DECREF(v);
+			Py_DECREF(w);
+			if (PyErr_Occurred())
+				return -2;
+			return c < 0 ? -1 : c > 0 ? 1 : 0;
+		}
+	}
+	else {
+		/* The coercion didn't do anything.
+		   Treat this the same as returning v and w unchanged. */
+		Py_INCREF(v);
+		Py_INCREF(w);
+	}
+
+	if (PyInstance_Check(v)) {
+		c = half_cmp(v, w);
+		if (c <= 1) {
+			Py_DECREF(v);
+			Py_DECREF(w);
+			return c;
+		}
+	}
+	if (PyInstance_Check(w)) {
+		c = half_cmp(w, v);
+		if (c <= 1) {
+			Py_DECREF(v);
+			Py_DECREF(w);
+			if (c >= -1)
+				c = -c;
+			return c;
+		}
+	}
+	Py_DECREF(v);
+	Py_DECREF(w);
+	return 2;
+}
+
+static int
+instance_nonzero(PyInstanceObject *self)
+{
+	PyObject *func, *res;
+	long outcome;
+	static PyObject *nonzerostr;
+
+	if (nonzerostr == NULL) {
+		nonzerostr = PyString_InternFromString("__nonzero__");
+		if (nonzerostr == NULL)
+			return -1;
+	}
+	if ((func = instance_getattr(self, nonzerostr)) == NULL) {
+		if (!PyErr_ExceptionMatches(PyExc_AttributeError))
+			return -1;
+		PyErr_Clear();
+		if (lenstr == NULL) {
+			lenstr = PyString_InternFromString("__len__");
+			if (lenstr == NULL)
+				return -1;
+		}
+		if ((func = instance_getattr(self, lenstr)) == NULL) {
+			if (!PyErr_ExceptionMatches(PyExc_AttributeError))
+				return -1;
+			PyErr_Clear();
+			/* Fall back to the default behavior:
+			   all instances are nonzero */
+			return 1;
+		}
+	}
+	res = PyEval_CallObject(func, (PyObject *)NULL);
+	Py_DECREF(func);
+	if (res == NULL)
+		return -1;
+	if (!PyInt_Check(res)) {
+		Py_DECREF(res);
+		PyErr_SetString(PyExc_TypeError,
+				"__nonzero__ should return an int");
+		return -1;
+	}
+	outcome = PyInt_AsLong(res);
+	Py_DECREF(res);
+	if (outcome < 0) {
+		PyErr_SetString(PyExc_ValueError,
+				"__nonzero__ should return >= 0");
+		return -1;
+	}
+	return outcome > 0;
+}
+
+static PyObject *
+instance_index(PyInstanceObject *self)
+{
+	PyObject *func, *res;
+	static PyObject *indexstr = NULL;
+
+	if (indexstr == NULL) {
+		indexstr = PyString_InternFromString("__index__");
+		if (indexstr == NULL)
+			return NULL;
+	}	
+	if ((func = instance_getattr(self, indexstr)) == NULL) {
+		if (!PyErr_ExceptionMatches(PyExc_AttributeError))
+			return NULL;
+		PyErr_Clear();
+		PyErr_SetString(PyExc_TypeError, 
+				"object cannot be interpreted as an index");
+		return NULL;
+	}
+	res = PyEval_CallObject(func, (PyObject *)NULL);
+	Py_DECREF(func);
+	return res;
+}
+
+
+UNARY(instance_invert, "__invert__")
+UNARY(_instance_trunc, "__trunc__")
+
+static PyObject *
+instance_int(PyInstanceObject *self)
+{
+	PyObject *truncated;
+	static PyObject *int_name;
+	if (int_name == NULL) {
+		int_name = PyString_InternFromString("__int__");
+		if (int_name == NULL)
+			return NULL;
+	}
+	if (PyObject_HasAttr((PyObject*)self, int_name))
+		return generic_unary_op(self, int_name);
+
+	truncated = _instance_trunc(self);
+	/* __trunc__ is specified to return an Integral type, but
+	   int() needs to return an int. */
+	return _PyNumber_ConvertIntegralToInt(
+		truncated,
+		"__trunc__ returned non-Integral (type %.200s)");
+}
+
+UNARY_FB(instance_long, "__long__", instance_int)
+UNARY(instance_float, "__float__")
+UNARY(instance_oct, "__oct__")
+UNARY(instance_hex, "__hex__")
+
+static PyObject *
+bin_power(PyObject *v, PyObject *w)
+{
+	return PyNumber_Power(v, w, Py_None);
+}
+
+/* This version is for ternary calls only (z != None) */
+static PyObject *
+instance_pow(PyObject *v, PyObject *w, PyObject *z)
+{
+	if (z == Py_None) {
+		return do_binop(v, w, "__pow__", "__rpow__", bin_power);
+	}
+	else {
+		PyObject *func;
+		PyObject *args;
+		PyObject *result;
+
+		/* XXX Doesn't do coercions... */
+		func = PyObject_GetAttrString(v, "__pow__");
+		if (func == NULL)
+			return NULL;
+		args = PyTuple_Pack(2, w, z);
+		if (args == NULL) {
+			Py_DECREF(func);
+			return NULL;
+		}
+		result = PyEval_CallObject(func, args);
+		Py_DECREF(func);
+		Py_DECREF(args);
+		return result;
+	}
+}
+
+static PyObject *
+bin_inplace_power(PyObject *v, PyObject *w)
+{
+	return PyNumber_InPlacePower(v, w, Py_None);
+}
+
+
+static PyObject *
+instance_ipow(PyObject *v, PyObject *w, PyObject *z)
+{
+	if (z == Py_None) {
+		return do_binop_inplace(v, w, "__ipow__", "__pow__",
+			"__rpow__", bin_inplace_power);
+	}
+	else {
+		/* XXX Doesn't do coercions... */
+		PyObject *func;
+		PyObject *args;
+		PyObject *result;
+
+		func = PyObject_GetAttrString(v, "__ipow__");
+		if (func == NULL) {
+			if (!PyErr_ExceptionMatches(PyExc_AttributeError))
+				return NULL;
+			PyErr_Clear();
+			return instance_pow(v, w, z);
+		}
+		args = PyTuple_Pack(2, w, z);
+		if (args == NULL) {
+			Py_DECREF(func);
+			return NULL;
+		}
+		result = PyEval_CallObject(func, args);
+		Py_DECREF(func);
+		Py_DECREF(args);
+		return result;
+	}
+}
+
+
+/* Map rich comparison operators to their __xx__ namesakes */
+#define NAME_OPS 6
+static PyObject **name_op = NULL;
+
+static int
+init_name_op(void)
+{
+	int i;
+	char *_name_op[] = {
+		"__lt__",
+		"__le__",
+		"__eq__",
+		"__ne__",
+		"__gt__",
+		"__ge__",
+	};
+
+	name_op = (PyObject **)malloc(sizeof(PyObject *) * NAME_OPS);
+	if (name_op == NULL)
+		return -1;
+	for (i = 0; i < NAME_OPS; ++i) {
+		name_op[i] = PyString_InternFromString(_name_op[i]);
+		if (name_op[i] == NULL)
+			return -1;
+	}
+	return 0;
+}
+
+static PyObject *
+half_richcompare(PyObject *v, PyObject *w, int op)
+{
+	PyObject *method;
+	PyObject *args;
+	PyObject *res;
+
+	assert(PyInstance_Check(v));
+
+	if (name_op == NULL) {
+		if (init_name_op() < 0)
+			return NULL;
+	}
+	/* If the instance doesn't define an __getattr__ method, use
+	   instance_getattr2 directly because it will not set an
+	   exception on failure. */
+	if (((PyInstanceObject *)v)->in_class->cl_getattr == NULL)
+		method = instance_getattr2((PyInstanceObject *)v,
+					   name_op[op]);
+	else
+		method = PyObject_GetAttr(v, name_op[op]);
+	if (method == NULL) {
+		if (PyErr_Occurred()) {
+			if (!PyErr_ExceptionMatches(PyExc_AttributeError))
+				return NULL;
+			PyErr_Clear();
+		}
+		res = Py_NotImplemented;
+		Py_INCREF(res);
+		return res;
+	}
+
+	args = PyTuple_Pack(1, w);
+	if (args == NULL) {
+		Py_DECREF(method);
+		return NULL;
+	}
+
+	res = PyEval_CallObject(method, args);
+	Py_DECREF(args);
+	Py_DECREF(method);
+
+	return res;
+}
+
+static PyObject *
+instance_richcompare(PyObject *v, PyObject *w, int op)
+{
+	PyObject *res;
+
+	if (PyInstance_Check(v)) {
+		res = half_richcompare(v, w, op);
+		if (res != Py_NotImplemented)
+			return res;
+		Py_DECREF(res);
+	}
+
+	if (PyInstance_Check(w)) {
+		res = half_richcompare(w, v, _Py_SwappedOp[op]);
+		if (res != Py_NotImplemented)
+			return res;
+		Py_DECREF(res);
+	}
+
+	Py_INCREF(Py_NotImplemented);
+	return Py_NotImplemented;
+}
+
+
+/* Get the iterator */
+static PyObject *
+instance_getiter(PyInstanceObject *self)
+{
+	PyObject *func;
+
+	if (iterstr == NULL) {
+		iterstr = PyString_InternFromString("__iter__");
+		if (iterstr == NULL)
+			return NULL;
+	}
+	if (getitemstr == NULL) {
+		getitemstr = PyString_InternFromString("__getitem__");
+		if (getitemstr == NULL)
+			return NULL;
+	}
+
+	if ((func = instance_getattr(self, iterstr)) != NULL) {
+		PyObject *res = PyEval_CallObject(func, (PyObject *)NULL);
+		Py_DECREF(func);
+		if (res != NULL && !PyIter_Check(res)) {
+			PyErr_Format(PyExc_TypeError,
+				     "__iter__ returned non-iterator "
+				     "of type '%.100s'",
+				     res->ob_type->tp_name);
+			Py_DECREF(res);
+			res = NULL;
+		}
+		return res;
+	}
+	if (!PyErr_ExceptionMatches(PyExc_AttributeError))
+		return NULL;
+	PyErr_Clear();
+	if ((func = instance_getattr(self, getitemstr)) == NULL) {
+		PyErr_SetString(PyExc_TypeError,
+				"iteration over non-sequence");
+		return NULL;
+	}
+	Py_DECREF(func);
+	return PySeqIter_New((PyObject *)self);
+}
+
+
+/* Call the iterator's next */
+static PyObject *
+instance_iternext(PyInstanceObject *self)
+{
+	PyObject *func;
+
+	if (nextstr == NULL) {
+		nextstr = PyString_InternFromString("next");
+		if (nextstr == NULL)
+			return NULL;
+	}
+
+	if ((func = instance_getattr(self, nextstr)) != NULL) {
+		PyObject *res = PyEval_CallObject(func, (PyObject *)NULL);
+		Py_DECREF(func);
+		if (res != NULL) {
+			return res;
+		}
+		if (PyErr_ExceptionMatches(PyExc_StopIteration)) {
+			PyErr_Clear();
+			return NULL;
+		}
+		return NULL;
+	}
+	PyErr_SetString(PyExc_TypeError, "instance has no next() method");
+	return NULL;
+}
+
+static PyObject *
+instance_call(PyObject *func, PyObject *arg, PyObject *kw)
+{
+	PyObject *res, *call = PyObject_GetAttrString(func, "__call__");
+	if (call == NULL) {
+		PyInstanceObject *inst = (PyInstanceObject*) func;
+		if (!PyErr_ExceptionMatches(PyExc_AttributeError))
+			return NULL;
+		PyErr_Clear();
+		PyErr_Format(PyExc_AttributeError,
+			     "%.200s instance has no __call__ method",
+			     PyString_AsString(inst->in_class->cl_name));
+		return NULL;
+	}
+	/* We must check and increment the recursion depth here. Scenario:
+	       class A:
+	           pass
+	       A.__call__ = A() # that's right
+	       a = A() # ok
+	       a() # infinite recursion
+	   This bounces between instance_call() and PyObject_Call() without
+	   ever hitting eval_frame() (which has the main recursion check). */
+	if (Py_EnterRecursiveCall(" in __call__")) {
+		res = NULL;
+	}
+	else {
+		res = PyObject_Call(call, arg, kw);
+		Py_LeaveRecursiveCall();
+	}
+	Py_DECREF(call);
+	return res;
+}
+
+
+static PyNumberMethods instance_as_number = {
+	instance_add,			/* nb_add */
+	instance_sub,			/* nb_subtract */
+	instance_mul,			/* nb_multiply */
+	instance_div,			/* nb_divide */
+	instance_mod,			/* nb_remainder */
+	instance_divmod,		/* nb_divmod */
+	instance_pow,			/* nb_power */
+	(unaryfunc)instance_neg,	/* nb_negative */
+	(unaryfunc)instance_pos,	/* nb_positive */
+	(unaryfunc)instance_abs,	/* nb_absolute */
+	(inquiry)instance_nonzero,	/* nb_nonzero */
+	(unaryfunc)instance_invert,	/* nb_invert */
+	instance_lshift,		/* nb_lshift */
+	instance_rshift,		/* nb_rshift */
+	instance_and,			/* nb_and */
+	instance_xor,			/* nb_xor */
+	instance_or,			/* nb_or */
+	instance_coerce,		/* nb_coerce */
+	(unaryfunc)instance_int,	/* nb_int */
+	(unaryfunc)instance_long,	/* nb_long */
+	(unaryfunc)instance_float,	/* nb_float */
+	(unaryfunc)instance_oct,	/* nb_oct */
+	(unaryfunc)instance_hex,	/* nb_hex */
+	instance_iadd,			/* nb_inplace_add */
+	instance_isub,			/* nb_inplace_subtract */
+	instance_imul,			/* nb_inplace_multiply */
+	instance_idiv,			/* nb_inplace_divide */
+	instance_imod,			/* nb_inplace_remainder */
+	instance_ipow,			/* nb_inplace_power */
+	instance_ilshift,		/* nb_inplace_lshift */
+	instance_irshift,		/* nb_inplace_rshift */
+	instance_iand,			/* nb_inplace_and */
+	instance_ixor,			/* nb_inplace_xor */
+	instance_ior,			/* nb_inplace_or */
+	instance_floordiv,		/* nb_floor_divide */
+	instance_truediv,		/* nb_true_divide */
+	instance_ifloordiv,		/* nb_inplace_floor_divide */
+	instance_itruediv,		/* nb_inplace_true_divide */
+	(unaryfunc)instance_index,	/* nb_index */
+};
+
+PyTypeObject PyInstance_Type = {
+	PyObject_HEAD_INIT(&PyType_Type)
+	0,
+	"instance",
+	sizeof(PyInstanceObject),
+	0,
+	(destructor)instance_dealloc,		/* tp_dealloc */
+	0,					/* tp_print */
+	0,					/* tp_getattr */
+	0,					/* tp_setattr */
+	instance_compare,			/* tp_compare */
+	(reprfunc)instance_repr,		/* tp_repr */
+	&instance_as_number,			/* tp_as_number */
+	&instance_as_sequence,			/* tp_as_sequence */
+	&instance_as_mapping,			/* tp_as_mapping */
+	(hashfunc)instance_hash,		/* tp_hash */
+	instance_call,				/* tp_call */
+	(reprfunc)instance_str,			/* tp_str */
+	(getattrofunc)instance_getattr,		/* tp_getattro */
+	(setattrofunc)instance_setattr,		/* tp_setattro */
+	0,					/* tp_as_buffer */
+	Py_TPFLAGS_DEFAULT | Py_TPFLAGS_HAVE_GC | Py_TPFLAGS_CHECKTYPES,/*tp_flags*/
+	instance_doc,				/* tp_doc */
+	(traverseproc)instance_traverse,	/* tp_traverse */
+	0,					/* tp_clear */
+	instance_richcompare,			/* tp_richcompare */
+ 	offsetof(PyInstanceObject, in_weakreflist), /* tp_weaklistoffset */
+	(getiterfunc)instance_getiter,		/* tp_iter */
+	(iternextfunc)instance_iternext,	/* tp_iternext */
+	0,					/* tp_methods */
+	0,					/* tp_members */
+	0,					/* tp_getset */
+	0,					/* tp_base */
+	0,					/* tp_dict */
+	0,					/* tp_descr_get */
+	0,					/* tp_descr_set */
+	0,					/* tp_dictoffset */
+	0,					/* tp_init */
+	0,					/* tp_alloc */
+	instance_new,				/* tp_new */
+};
+
+
+/* Instance method objects are used for two purposes:
+   (a) as bound instance methods (returned by instancename.methodname)
+   (b) as unbound methods (returned by ClassName.methodname)
+   In case (b), im_self is NULL
+*/
+
+PyObject *
+PyMethod_New(PyObject *func, PyObject *self, PyObject *klass)
+{
+	register PyMethodObject *im;
+	if (!PyCallable_Check(func)) {
+		PyErr_BadInternalCall();
+		return NULL;
+	}
+	im = free_list;
+	if (im != NULL) {
+		free_list = (PyMethodObject *)(im->im_self);
+		PyObject_INIT(im, &PyMethod_Type);
+		numfree--;
+	}
+	else {
+		im = PyObject_GC_New(PyMethodObject, &PyMethod_Type);
+		if (im == NULL)
+			return NULL;
+	}
+	im->im_weakreflist = NULL;
+	Py_INCREF(func);
+	im->im_func = func;
+	Py_XINCREF(self);
+	im->im_self = self;
+	Py_XINCREF(klass);
+	im->im_class = klass;
+	_PyObject_GC_TRACK(im);
+	return (PyObject *)im;
+}
+
+/* Descriptors for PyMethod attributes */
+
+/* im_class, im_func and im_self are stored in the PyMethod object */
+
+#define OFF(x) offsetof(PyMethodObject, x)
+
+static PyMemberDef instancemethod_memberlist[] = {
+	{"im_class",	T_OBJECT,	OFF(im_class),	READONLY|RESTRICTED,
+	 "the class associated with a method"},
+	{"im_func",	T_OBJECT,	OFF(im_func),	READONLY|RESTRICTED,
+	 "the function (or other callable) implementing a method"},
+	{"__func__",	T_OBJECT,	OFF(im_func),	READONLY|RESTRICTED,
+	 "the function (or other callable) implementing a method"},
+	{"im_self",	T_OBJECT,	OFF(im_self),	READONLY|RESTRICTED,
+	 "the instance to which a method is bound; None for unbound methods"},
+	{"__self__",	T_OBJECT,	OFF(im_self),	READONLY|RESTRICTED,
+	 "the instance to which a method is bound; None for unbound methods"},
+	{NULL}	/* Sentinel */
+};
+
+/* Christian Tismer argued convincingly that method attributes should
+   (nearly) always override function attributes.
+   The one exception is __doc__; there's a default __doc__ which
+   should only be used for the class, not for instances */
+
+static PyObject *
+instancemethod_get_doc(PyMethodObject *im, void *context)
+{
+	static PyObject *docstr;
+	if (docstr == NULL) {
+		docstr= PyString_InternFromString("__doc__");
+		if (docstr == NULL)
+			return NULL;
+	}
+	return PyObject_GetAttr(im->im_func, docstr);
+}
+
+static PyGetSetDef instancemethod_getset[] = {
+	{"__doc__", (getter)instancemethod_get_doc, NULL, NULL},
+	{0}
+};
+
+static PyObject *
+instancemethod_getattro(PyObject *obj, PyObject *name)
+{
+	PyMethodObject *im = (PyMethodObject *)obj;
+	PyTypeObject *tp = obj->ob_type;
+	PyObject *descr = NULL;
+
+	if (PyType_HasFeature(tp, Py_TPFLAGS_HAVE_CLASS)) {
+		if (tp->tp_dict == NULL) {
+			if (PyType_Ready(tp) < 0)
+				return NULL;
+		}
+		descr = _PyType_Lookup(tp, name);
+	}
+
+	if (descr != NULL) {
+		descrgetfunc f = TP_DESCR_GET(descr->ob_type);
+		if (f != NULL)
+			return f(descr, obj, (PyObject *)obj->ob_type);
+		else {
+			Py_INCREF(descr);
+			return descr;
+		}
+	}
+
+	return PyObject_GetAttr(im->im_func, name);
+}
+
+PyDoc_STRVAR(instancemethod_doc,
+"instancemethod(function, instance, class)\n\
+\n\
+Create an instance method object.");
+
+static PyObject *
+instancemethod_new(PyTypeObject* type, PyObject* args, PyObject *kw)
+{
+	PyObject *func;
+	PyObject *self;
+	PyObject *classObj = NULL;
+
+	if (!_PyArg_NoKeywords("instancemethod", kw))
+		return NULL;
+	if (!PyArg_UnpackTuple(args, "instancemethod", 2, 3,
+			      &func, &self, &classObj))
+		return NULL;
+	if (!PyCallable_Check(func)) {
+		PyErr_SetString(PyExc_TypeError,
+				"first argument must be callable");
+		return NULL;
+	}
+	if (self == Py_None)
+		self = NULL;
+	if (self == NULL && classObj == NULL) {
+		PyErr_SetString(PyExc_TypeError,
+			"unbound methods must have non-NULL im_class");
+		return NULL;
+	}
+
+	return PyMethod_New(func, self, classObj);
+}
+
+static void
+instancemethod_dealloc(register PyMethodObject *im)
+{
+	_PyObject_GC_UNTRACK(im);
+	if (im->im_weakreflist != NULL)
+		PyObject_ClearWeakRefs((PyObject *)im);
+	Py_DECREF(im->im_func);
+	Py_XDECREF(im->im_self);
+	Py_XDECREF(im->im_class);
+	if (numfree < PyMethod_MAXFREELIST) {
+		im->im_self = (PyObject *)free_list;
+		free_list = im;
+		numfree++;
+	}
+	else {
+		PyObject_GC_Del(im);
+	}
+}
+
+static int
+instancemethod_compare(PyMethodObject *a, PyMethodObject *b)
+{
+	int cmp;
+	cmp = PyObject_Compare(a->im_func, b->im_func);
+	if (cmp)
+		return cmp;
+
+	if (a->im_self == b->im_self)
+		return 0;
+	if (a->im_self == NULL || b->im_self == NULL)
+		return (a->im_self < b->im_self) ? -1 : 1;
+	else
+		return PyObject_Compare(a->im_self, b->im_self);
+}
+
+static PyObject *
+instancemethod_repr(PyMethodObject *a)
+{
+	PyObject *self = a->im_self;
+	PyObject *func = a->im_func;
+	PyObject *klass = a->im_class;
+	PyObject *funcname = NULL, *klassname = NULL, *result = NULL;
+	char *sfuncname = "?", *sklassname = "?";
+
+	funcname = PyObject_GetAttrString(func, "__name__");
+	if (funcname == NULL) {
+		if (!PyErr_ExceptionMatches(PyExc_AttributeError))
+			return NULL;
+		PyErr_Clear();
+	}
+	else if (!PyString_Check(funcname)) {
+		Py_DECREF(funcname);
+		funcname = NULL;
+	}
+	else
+		sfuncname = PyString_AS_STRING(funcname);
+	if (klass == NULL)
+		klassname = NULL;
+	else {
+		klassname = PyObject_GetAttrString(klass, "__name__");
+		if (klassname == NULL) {
+			if (!PyErr_ExceptionMatches(PyExc_AttributeError))
+				return NULL;
+			PyErr_Clear();
+		}
+		else if (!PyString_Check(klassname)) {
+			Py_DECREF(klassname);
+			klassname = NULL;
+		}
+		else
+			sklassname = PyString_AS_STRING(klassname);
+	}
+	if (self == NULL)
+		result = PyString_FromFormat("<unbound method %s.%s>",
+					     sklassname, sfuncname);
+	else {
+		/* XXX Shouldn't use repr() here! */
+		PyObject *selfrepr = PyObject_Repr(self);
+		if (selfrepr == NULL)
+			goto fail;
+		if (!PyString_Check(selfrepr)) {
+			Py_DECREF(selfrepr);
+			goto fail;
+		}
+		result = PyString_FromFormat("<bound method %s.%s of %s>",
+					     sklassname, sfuncname,
+					     PyString_AS_STRING(selfrepr));
+		Py_DECREF(selfrepr);
+	}
+  fail:
+	Py_XDECREF(funcname);
+	Py_XDECREF(klassname);
+	return result;
+}
+
+static long
+instancemethod_hash(PyMethodObject *a)
+{
+	long x, y;
+	if (a->im_self == NULL)
+		x = PyObject_Hash(Py_None);
+	else
+		x = PyObject_Hash(a->im_self);
+	if (x == -1)
+		return -1;
+	y = PyObject_Hash(a->im_func);
+	if (y == -1)
+		return -1;
+	x = x ^ y;
+	if (x == -1)
+		x = -2;
+	return x;
+}
+
+static int
+instancemethod_traverse(PyMethodObject *im, visitproc visit, void *arg)
+{
+	Py_VISIT(im->im_func);
+	Py_VISIT(im->im_self);
+	Py_VISIT(im->im_class);
+	return 0;
+}
+
+static void
+getclassname(PyObject *klass, char *buf, int bufsize)
+{
+	PyObject *name;
+
+	assert(bufsize > 1);
+	strcpy(buf, "?"); /* Default outcome */
+	if (klass == NULL)
+		return;
+	name = PyObject_GetAttrString(klass, "__name__");
+	if (name == NULL) {
+		/* This function cannot return an exception */
+		PyErr_Clear();
+		return;
+	}
+	if (PyString_Check(name)) {
+		strncpy(buf, PyString_AS_STRING(name), bufsize);
+		buf[bufsize-1] = '\0';
+	}
+	Py_DECREF(name);
+}
+
+static void
+getinstclassname(PyObject *inst, char *buf, int bufsize)
+{
+	PyObject *klass;
+
+	if (inst == NULL) {
+		assert(bufsize > 0 && (size_t)bufsize > strlen("nothing"));
+		strcpy(buf, "nothing");
+		return;
+	}
+
+	klass = PyObject_GetAttrString(inst, "__class__");
+	if (klass == NULL) {
+		/* This function cannot return an exception */
+		PyErr_Clear();
+		klass = (PyObject *)(inst->ob_type);
+		Py_INCREF(klass);
+	}
+	getclassname(klass, buf, bufsize);
+	Py_XDECREF(klass);
+}
+
+static PyObject *
+instancemethod_call(PyObject *func, PyObject *arg, PyObject *kw)
+{
+	PyObject *self = PyMethod_GET_SELF(func);
+	PyObject *klass = PyMethod_GET_CLASS(func);
+	PyObject *result;
+
+	func = PyMethod_GET_FUNCTION(func);
+	if (self == NULL) {
+		/* Unbound methods must be called with an instance of
+		   the class (or a derived class) as first argument */
+		int ok;
+		if (PyTuple_Size(arg) >= 1)
+			self = PyTuple_GET_ITEM(arg, 0);
+		if (self == NULL)
+			ok = 0;
+		else {
+			ok = PyObject_IsInstance(self, klass);
+			if (ok < 0)
+				return NULL;
+		}
+		if (!ok) {
+			char clsbuf[256];
+			char instbuf[256];
+			getclassname(klass, clsbuf, sizeof(clsbuf));
+			getinstclassname(self, instbuf, sizeof(instbuf));
+			PyErr_Format(PyExc_TypeError,
+				     "unbound method %s%s must be called with "
+				     "%s instance as first argument "
+				     "(got %s%s instead)",
+				     PyEval_GetFuncName(func),
+				     PyEval_GetFuncDesc(func),
+				     clsbuf,
+				     instbuf,
+				     self == NULL ? "" : " instance");
+			return NULL;
+		}
+		Py_INCREF(arg);
+	}
+	else {
+		Py_ssize_t argcount = PyTuple_Size(arg);
+		PyObject *newarg = PyTuple_New(argcount + 1);
+		int i;
+		if (newarg == NULL)
+			return NULL;
+		Py_INCREF(self);
+		PyTuple_SET_ITEM(newarg, 0, self);
+		for (i = 0; i < argcount; i++) {
+			PyObject *v = PyTuple_GET_ITEM(arg, i);
+			Py_XINCREF(v);
+			PyTuple_SET_ITEM(newarg, i+1, v);
+		}
+		arg = newarg;
+	}
+	result = PyObject_Call((PyObject *)func, arg, kw);
+	Py_DECREF(arg);
+	return result;
+}
+
+static PyObject *
+instancemethod_descr_get(PyObject *meth, PyObject *obj, PyObject *cls)
+{
+	/* Don't rebind an already bound method, or an unbound method
+	   of a class that's not a base class of cls. */
+
+	if (PyMethod_GET_SELF(meth) != NULL) {
+		/* Already bound */
+		Py_INCREF(meth);
+		return meth;
+	}
+	/* No, it is an unbound method */
+	if (PyMethod_GET_CLASS(meth) != NULL && cls != NULL) {
+		/* Do subclass test.  If it fails, return meth unchanged. */
+		int ok = PyObject_IsSubclass(cls, PyMethod_GET_CLASS(meth));
+		if (ok < 0)
+			return NULL;
+		if (!ok) {
+			Py_INCREF(meth);
+			return meth;
+		}
+	}
+	/* Bind it to obj */
+	return PyMethod_New(PyMethod_GET_FUNCTION(meth), obj, cls);
+}
+
+PyTypeObject PyMethod_Type = {
+	PyObject_HEAD_INIT(&PyType_Type)
+	0,
+	"instancemethod",
+	sizeof(PyMethodObject),
+	0,
+	(destructor)instancemethod_dealloc,	/* tp_dealloc */
+	0,					/* tp_print */
+	0,					/* tp_getattr */
+	0,					/* tp_setattr */
+	(cmpfunc)instancemethod_compare,	/* tp_compare */
+	(reprfunc)instancemethod_repr,		/* tp_repr */
+	0,					/* tp_as_number */
+	0,					/* tp_as_sequence */
+	0,					/* tp_as_mapping */
+	(hashfunc)instancemethod_hash,		/* tp_hash */
+	instancemethod_call,			/* tp_call */
+	0,					/* tp_str */
+	instancemethod_getattro,		/* tp_getattro */
+	PyObject_GenericSetAttr,		/* tp_setattro */
+	0,					/* tp_as_buffer */
+	Py_TPFLAGS_DEFAULT | Py_TPFLAGS_HAVE_GC  | Py_TPFLAGS_HAVE_WEAKREFS, /* tp_flags */
+	instancemethod_doc,			/* tp_doc */
+	(traverseproc)instancemethod_traverse,	/* tp_traverse */
+	0,					/* tp_clear */
+	0,					/* tp_richcompare */
+ 	offsetof(PyMethodObject, im_weakreflist), /* tp_weaklistoffset */
+	0,					/* tp_iter */
+	0,					/* tp_iternext */
+	0,					/* tp_methods */
+	instancemethod_memberlist,		/* tp_members */
+	instancemethod_getset,			/* tp_getset */
+	0,					/* tp_base */
+	0,					/* tp_dict */
+	instancemethod_descr_get,		/* tp_descr_get */
+	0,					/* tp_descr_set */
+	0,					/* tp_dictoffset */
+	0,					/* tp_init */
+	0,					/* tp_alloc */
+	instancemethod_new,			/* tp_new */
+};
+
+/* Clear out the free list */
+
+int
+PyMethod_ClearFreeList(void)
+{
+	int freelist_size = numfree;
+	
+	while (free_list) {
+		PyMethodObject *im = free_list;
+		free_list = (PyMethodObject *)(im->im_self);
+		PyObject_GC_Del(im);
+		numfree--;
+	}
+	assert(numfree == 0);
+	return freelist_size;
+}
+
+void
+PyMethod_Fini(void)
+{
+	(void)PyMethod_ClearFreeList();
+}