v w Action
-------------------------------------------------------------------
new new w.op(v,w)[*], v.op(v,w), w.op(v,w)
new old v.op(v,w), coerce(v,w), v.op(v,w)
old new w.op(v,w), coerce(v,w), v.op(v,w)
old old coerce(v,w), v.op(v,w)
[*] only when v->ob_type != w->ob_type && w->ob_type is a subclass of
v->ob_type
Legend:
-------
* new == new style number
* old == old style number
* Action indicates the order in which operations are tried until either
a valid result is produced or an error occurs.
*** In some cases, w.op is called before v.op; see binary_op1. ***
v w z Action
-------------------------------------------------------------------
new new new v.op(v,w,z), w.op(v,w,z), z.op(v,w,z)
new old new v.op(v,w,z), z.op(v,w,z), coerce(v,w,z), v.op(v,w,z)
old new new w.op(v,w,z), z.op(v,w,z), coerce(v,w,z), v.op(v,w,z)
old old new z.op(v,w,z), coerce(v,w,z), v.op(v,w,z)
new new old v.op(v,w,z), w.op(v,w,z), coerce(v,w,z), v.op(v,w,z)
new old old v.op(v,w,z), coerce(v,w,z), v.op(v,w,z)
old new old w.op(v,w,z), coerce(v,w,z), v.op(v,w,z)
old old old coerce(v,w,z), v.op(v,w,z)
Legend:
-------
* new == new style number
* old == old style number
* Action indicates the order in which operations are tried until either
a valid result is produced or an error occurs.
* coerce(v,w,z) actually does: coerce(v,w), coerce(v,z), coerce(w,z) and
only if z != Py_None; if z == Py_None, then it is treated as absent
variable and only coerce(v,w) is tried.
mv = v->ob_type->tp_as_number;
mw = w->ob_type->tp_as_number;
if (mv != NULL && NEW_STYLE_NUMBER(v))
slotv = NB_TERNOP(mv, op_slot);
if (w->ob_type != v->ob_type &&
mw != NULL && NEW_STYLE_NUMBER(w)) {
slotw = NB_TERNOP(mw, op_slot);
if (slotw == slotv)
slotw = NULL;
}
if (slotv) {
if (slotw && PyType_IsSubtype(w->ob_type, v->ob_type)) {
x = slotw(v, w, z);
if (x != Py_NotImplemented)
return x;
Py_DECREF(x); /* can't do it */
slotw = NULL;
}
x = slotv(v, w, z);
if (x != Py_NotImplemented)
return x;
Py_DECREF(x); /* can't do it */
}
if (slotw) {
x = slotw(v, w, z);
if (x != Py_NotImplemented)
return x;
Py_DECREF(x); /* can't do it */
}
mz = z->ob_type->tp_as_number;
if (mz != NULL && NEW_STYLE_NUMBER(z)) {
slotz = NB_TERNOP(mz, op_slot);
if (slotz == slotv || slotz == slotw)
slotz = NULL;
if (slotz) {
x = slotz(v, w, z);
if (x != Py_NotImplemented)
return x;
Py_DECREF(x); /* can't do it */
}
}
if (!NEW_STYLE_NUMBER(v) || !NEW_STYLE_NUMBER(w) ||
(z != Py_None && !NEW_STYLE_NUMBER(z))) {
/* we have an old style operand, coerce */
PyObject *v1, *z1, *w2, *z2;
int c;
c = PyNumber_Coerce(&v, &w);
if (c != 0)
goto error3;
/* Special case: if the third argument is None, it is
treated as absent argument and not coerced. */
if (z == Py_None) {
if (v->ob_type->tp_as_number) {
slotz = NB_TERNOP(v->ob_type->tp_as_number,
op_slot);
if (slotz)
x = slotz(v, w, z);
else
c = -1;
}
else
c = -1;
goto error2;
}
v1 = v;
z1 = z;
c = PyNumber_Coerce(&v1, &z1);
if (c != 0)
goto error2;
w2 = w;
z2 = z1;
c = PyNumber_Coerce(&w2, &z2);
if (c != 0)
goto error1;
if (v1->ob_type->tp_as_number != NULL) {
slotv = NB_TERNOP(v1->ob_type->tp_as_number,
op_slot);
if (slotv)
x = slotv(v1, w2, z2);
else
c = -1;
}
else
c = -1;
/* The in-place operators are defined to fall back to the 'normal',
non in-place operations, if the in-place methods are not in place.
- If the left hand object has the appropriate struct members, and
they are filled, call the appropriate function and return the
result. No coercion is done on the arguments; the left-hand object
is the one the operation is performed on, and it's up to the
function to deal with the right-hand object.
- Otherwise, in-place modification is not supported. Handle it exactly as
a non in-place operation of the same kind.
PyObject *
PyNumber_InPlaceAdd(PyObject *v, PyObject *w)
{
PyObject *result = binary_iop1(v, w, NB_SLOT(nb_inplace_add),
NB_SLOT(nb_add));
if (result == Py_NotImplemented) {
PySequenceMethods *m = v->ob_type->tp_as_sequence;
Py_DECREF(result);
if (m != NULL) {
binaryfunc f = NULL;
if (HASINPLACE(v))
f = m->sq_inplace_concat;
if (f == NULL)
f = m->sq_concat;
if (f != NULL)
return (*f)(v, w);
}
result = binop_type_error(v, w, "+=");
}
return result;
}
PyObject *
PyNumber_InPlaceMultiply(PyObject *v, PyObject *w)
{
PyObject *result = binary_iop1(v, w, NB_SLOT(nb_inplace_multiply),
NB_SLOT(nb_multiply));
if (result == Py_NotImplemented) {
ssizeargfunc f = NULL;
PySequenceMethods *mv = v->ob_type->tp_as_sequence;
PySequenceMethods *mw = w->ob_type->tp_as_sequence;
Py_DECREF(result);
if (mv != NULL) {
if (HASINPLACE(v))
f = mv->sq_inplace_repeat;
if (f == NULL)
f = mv->sq_repeat;
if (f != NULL)
return sequence_repeat(f, v, w);
}
else if (mw != NULL) {
/* Note that the right hand operand should not be
* mutated in this case so sq_inplace_repeat is not
* used. */
if (mw->sq_repeat)
return sequence_repeat(mw->sq_repeat, w, v);
}
result = binop_type_error(v, w, "*=");
}
return result;
}
if (o == NULL)
return null_error();
m = o->ob_type->tp_as_number;
if (m && m->nb_absolute)
return m->nb_absolute(o);
return type_error("bad operand type for abs(): '%.200s'", o);
}
/* Add a check for embedded NULL-bytes in the argument. */
static PyObject *
int_from_string(const char *s, Py_ssize_t len)
{
char *end;
PyObject *x;
x = PyInt_FromString((char*)s, &end, 10);
if (x == NULL)
return NULL;
if (end != s + len) {
PyErr_SetString(PyExc_ValueError,
"null byte in argument for int()");
Py_DECREF(x);
return NULL;
}
return x;
}
/* Return a Python Int or Long from the object item
Raise TypeError if the result is not an int-or-long
or if the object cannot be interpreted as an index.
*/
PyObject *
PyNumber_Index(PyObject *item)
{
PyObject *result = NULL;
if (item == NULL)
return null_error();
if (PyInt_Check(item) || PyLong_Check(item)) {
Py_INCREF(item);
return item;
}
if (PyIndex_Check(item)) {
result = item->ob_type->tp_as_number->nb_index(item);
if (result &&
!PyInt_Check(result) && !PyLong_Check(result)) {
PyErr_Format(PyExc_TypeError,
"__index__ returned non-(int,long) " \
"(type %.200s)",
result->ob_type->tp_name);
Py_DECREF(result);
return NULL;
}
}
else {
PyErr_Format(PyExc_TypeError,
"'%.200s' object cannot be interpreted "
"as an index", item->ob_type->tp_name);
}
return result;
}
/* Return an error on Overflow only if err is not NULL*/
/* We're done if PyInt_AsSsize_t() returns without error. */
result = PyInt_AsSsize_t(value);
if (result != -1 || !(runerr = PyErr_Occurred()))
goto finish;
/* Error handling code -- only manage OverflowError differently */
if (!PyErr_GivenExceptionMatches(runerr, PyExc_OverflowError))
goto finish;
PyErr_Clear();
/* If no error-handling desired then the default clipping
is sufficient.
*/
if (!err) {
assert(PyLong_Check(value));
/* Whether or not it is less than or equal to
zero is determined by the sign of ob_size
*/
if (_PyLong_Sign(value) < 0)
result = PY_SSIZE_T_MIN;
else
result = PY_SSIZE_T_MAX;
}
else {
/* Otherwise replace the error with caller's error object. */
PyErr_Format(err,
"cannot fit '%.200s' into an index-sized integer",
item->ob_type->tp_name);
}
if (o == NULL)
return null_error();
if (PyInt_CheckExact(o)) {
Py_INCREF(o);
return o;
}
m = o->ob_type->tp_as_number;
if (m && m->nb_int) { /* This should include subclasses of int */
PyObject *res = m->nb_int(o);
if (res && (!PyInt_Check(res) && !PyLong_Check(res))) {
PyErr_Format(PyExc_TypeError,
"__int__ returned non-int (type %.200s)",
res->ob_type->tp_name);
Py_DECREF(res);
return NULL;
}
return res;
}
if (PyInt_Check(o)) { /* A int subclass without nb_int */
PyIntObject *io = (PyIntObject*)o;
return PyInt_FromLong(io->ob_ival);
}
if (PyString_Check(o))
return int_from_string(PyString_AS_STRING(o),
PyString_GET_SIZE(o));
#ifdef Py_USING_UNICODE
if (PyUnicode_Check(o))
return PyInt_FromUnicode(PyUnicode_AS_UNICODE(o),
PyUnicode_GET_SIZE(o),
10);
#endif
if (!PyObject_AsCharBuffer(o, &buffer, &buffer_len))
return int_from_string((char*)buffer, buffer_len);
return type_error("int() argument must be a string or a "
"number, not '%.200s'", o);
}
/* Add a check for embedded NULL-bytes in the argument. */
static PyObject *
long_from_string(const char *s, Py_ssize_t len)
{
char *end;
PyObject *x;
x = PyLong_FromString((char*)s, &end, 10);
if (x == NULL)
return NULL;
if (end != s + len) {
PyErr_SetString(PyExc_ValueError,
"null byte in argument for long()");
Py_DECREF(x);
return NULL;
}
return x;
}
if (o == NULL)
return null_error();
m = o->ob_type->tp_as_number;
if (m && m->nb_long) { /* This should include subclasses of long */
PyObject *res = m->nb_long(o);
if (res && (!PyInt_Check(res) && !PyLong_Check(res))) {
PyErr_Format(PyExc_TypeError,
"__long__ returned non-long (type %.200s)",
res->ob_type->tp_name);
Py_DECREF(res);
return NULL;
}
return res;
}
if (PyLong_Check(o)) /* A long subclass without nb_long */
return _PyLong_Copy((PyLongObject *)o);
if (PyString_Check(o))
/* need to do extra error checking that PyLong_FromString()
* doesn't do. In particular long('9.5') must raise an
* exception, not truncate the float.
*/
return long_from_string(PyString_AS_STRING(o),
PyString_GET_SIZE(o));
#ifdef Py_USING_UNICODE
if (PyUnicode_Check(o))
/* The above check is done in PyLong_FromUnicode(). */
return PyLong_FromUnicode(PyUnicode_AS_UNICODE(o),
PyUnicode_GET_SIZE(o),
10);
#endif
if (!PyObject_AsCharBuffer(o, &buffer, &buffer_len))
return long_from_string(buffer, buffer_len);
return type_error("long() argument must be a string or a "
"number, not '%.200s'", o);
}
m = s->ob_type->tp_as_sequence;
if (m && m->sq_concat)
return m->sq_concat(s, o);
/* Instances of user classes defining an __add__() method only
have an nb_add slot, not an sq_concat slot. So we fall back
to nb_add if both arguments appear to be sequences. */
if (PySequence_Check(s) && PySequence_Check(o)) {
PyObject *result = binary_op1(s, o, NB_SLOT(nb_add));
if (result != Py_NotImplemented)
return result;
Py_DECREF(result);
}
return type_error("'%.200s' object can't be concatenated", s);
}
m = o->ob_type->tp_as_sequence;
if (m && m->sq_repeat)
return m->sq_repeat(o, count);
/* Instances of user classes defining a __mul__() method only
have an nb_multiply slot, not an sq_repeat slot. so we fall back
to nb_multiply if o appears to be a sequence. */
if (PySequence_Check(o)) {
PyObject *n, *result;
n = PyInt_FromSsize_t(count);
if (n == NULL)
return NULL;
result = binary_op1(o, n, NB_SLOT(nb_multiply));
Py_DECREF(n);
if (result != Py_NotImplemented)
return result;
Py_DECREF(result);
}
return type_error("'%.200s' object can't be repeated", o);
}
m = s->ob_type->tp_as_sequence;
if (m && m->sq_item) {
if (i < 0) {
if (m->sq_length) {
Py_ssize_t l = (*m->sq_length)(s);
if (l < 0)
return NULL;
i += l;
}
}
return m->sq_item(s, i);
}
return type_error("'%.200s' object is unindexable", s);
}
m = s->ob_type->tp_as_sequence;
if (m && m->sq_slice) {
if (i1 < 0 || i2 < 0) {
if (m->sq_length) {
Py_ssize_t l = (*m->sq_length)(s);
if (l < 0)
return NULL;
if (i1 < 0)
i1 += l;
if (i2 < 0)
i2 += l;
}
}
return m->sq_slice(s, i1, i2);
} else if ((mp = s->ob_type->tp_as_mapping) && mp->mp_subscript) {
PyObject *res;
PyObject *slice = _PySlice_FromIndices(i1, i2);
if (!slice)
return NULL;
res = mp->mp_subscript(s, slice);
Py_DECREF(slice);
return res;
}
return type_error("'%.200s' object is unsliceable", s);
}
int
PySequence_SetItem(PyObject *s, Py_ssize_t i, PyObject *o)
{
PySequenceMethods *m;
if (s == NULL) {
null_error();
return -1;
}
m = s->ob_type->tp_as_sequence;
if (m && m->sq_ass_item) {
if (i < 0) {
if (m->sq_length) {
Py_ssize_t l = (*m->sq_length)(s);
if (l < 0)
return -1;
i += l;
}
}
return m->sq_ass_item(s, i, o);
}
type_error("'%.200s' object does not support item assignment", s);
return -1;
}
int
PySequence_DelItem(PyObject *s, Py_ssize_t i)
{
PySequenceMethods *m;
if (s == NULL) {
null_error();
return -1;
}
m = s->ob_type->tp_as_sequence;
if (m && m->sq_ass_item) {
if (i < 0) {
if (m->sq_length) {
Py_ssize_t l = (*m->sq_length)(s);
if (l < 0)
return -1;
i += l;
}
}
return m->sq_ass_item(s, i, (PyObject *)NULL);
}
type_error("'%.200s' object doesn't support item deletion", s);
return -1;
}
/* Special-case the common tuple and list cases, for efficiency. */
if (PyTuple_CheckExact(v)) {
/* Note that we can't know whether it's safe to return
a tuple *subclass* instance as-is, hence the restriction
to exact tuples here. In contrast, lists always make
a copy, so there's no need for exactness below. */
Py_INCREF(v);
return v;
}
if (PyList_Check(v))
return PyList_AsTuple(v);
/* Get iterator. */
it = PyObject_GetIter(v);
if (it == NULL)
return NULL;
/* Guess result size and allocate space. */
n = _PyObject_LengthHint(v);
if (n < 0) {
if (!PyErr_ExceptionMatches(PyExc_TypeError) &&
!PyErr_ExceptionMatches(PyExc_AttributeError)) {
Py_DECREF(it);
return NULL;
}
PyErr_Clear();
n = 10; /* arbitrary */
}
result = PyTuple_New(n);
if (result == NULL)
goto Fail;
/* Fill the tuple. */
for (j = 0; ; ++j) {
PyObject *item = PyIter_Next(it);
if (item == NULL) {
if (PyErr_Occurred())
goto Fail;
break;
}
if (j >= n) {
Py_ssize_t oldn = n;
/* The over-allocation strategy can grow a bit faster
than for lists because unlike lists the
over-allocation isn't permanent -- we reclaim
the excess before the end of this routine.
So, grow by ten and then add 25%.
*/
n += 10;
n += n >> 2;
if (n < oldn) {
/* Check for overflow */
PyErr_NoMemory();
Py_DECREF(item);
goto Fail;
}
if (_PyTuple_Resize(&result, n) != 0) {
Py_DECREF(item);
goto Fail;
}
}
PyTuple_SET_ITEM(result, j, item);
}
/* Cut tuple back if guess was too large. */
if (j < n &&
_PyTuple_Resize(&result, j) != 0)
goto Fail;
if (PyList_CheckExact(v) || PyTuple_CheckExact(v)) {
Py_INCREF(v);
return v;
}
it = PyObject_GetIter(v);
if (it == NULL) {
if (PyErr_ExceptionMatches(PyExc_TypeError))
PyErr_SetString(PyExc_TypeError, m);
return NULL;
}
v = PySequence_List(it);
Py_DECREF(it);
return v;
}
/* Iterate over seq. Result depends on the operation:
PY_ITERSEARCH_COUNT: -1 if error, else # of times obj appears in seq.
PY_ITERSEARCH_INDEX: 0-based index of first occurence of obj in seq;
set ValueError and return -1 if none found; also return -1 on error.
Py_ITERSEARCH_CONTAINS: return 1 if obj in seq, else 0; -1 on error.
*/
Py_ssize_t
_PySequence_IterSearch(PyObject *seq, PyObject *obj, int operation)
{
Py_ssize_t n;
int wrapped; /* for PY_ITERSEARCH_INDEX, true iff n wrapped around */
PyObject *it; /* iter(seq) */
it = PyObject_GetIter(seq);
if (it == NULL) {
type_error("argument of type '%.200s' is not iterable", seq);
return -1;
}
n = wrapped = 0;
for (;;) {
int cmp;
PyObject *item = PyIter_Next(it);
if (item == NULL) {
if (PyErr_Occurred())
goto Fail;
break;
}
cmp = PyObject_RichCompareBool(obj, item, Py_EQ);
Py_DECREF(item);
if (cmp < 0)
goto Fail;
if (cmp > 0) {
switch (operation) {
case PY_ITERSEARCH_COUNT:
if (n == PY_SSIZE_T_MAX) {
PyErr_SetString(PyExc_OverflowError,
"count exceeds C integer size");
goto Fail;
}
++n;
break;
case PY_ITERSEARCH_INDEX:
if (wrapped) {
PyErr_SetString(PyExc_OverflowError,
"index exceeds C integer size");
goto Fail;
}
goto Done;
case PY_ITERSEARCH_CONTAINS:
n = 1;
goto Done;
default:
assert(!"unknown operation");
}
}
if (operation == PY_ITERSEARCH_INDEX) {
if (n == PY_SSIZE_T_MAX)
wrapped = 1;
++n;
}
}
if (operation != PY_ITERSEARCH_INDEX)
goto Done;
PyErr_SetString(PyExc_ValueError,
"sequence.index(x): x not in sequence");
/* fall into failure code */
Fail:
n = -1;
/* fall through */
Done:
Py_DECREF(it);
return n;
}
/* Return # of times o appears in s. */
Py_ssize_t
PySequence_Count(PyObject *s, PyObject *o)
{
return _PySequence_IterSearch(s, o, PY_ITERSEARCH_COUNT);
}
/* Return -1 if error; 1 if ob in seq; 0 if ob not in seq.
* Use sq_contains if possible, else defer to _PySequence_IterSearch().
*/
int
PySequence_Contains(PyObject *seq, PyObject *ob)
{
Py_ssize_t result;
if (PyType_HasFeature(seq->ob_type, Py_TPFLAGS_HAVE_SEQUENCE_IN)) {
PySequenceMethods *sqm = seq->ob_type->tp_as_sequence;
if (sqm != NULL && sqm->sq_contains != NULL)
return (*sqm->sq_contains)(seq, ob);
}
result = _PySequence_IterSearch(seq, ob, PY_ITERSEARCH_CONTAINS);
return Py_SAFE_DOWNCAST(result, Py_ssize_t, int);
}
/* abstract_get_bases() has logically 4 return states, with a sort of 0th
* state that will almost never happen.
*
* 0. creating the __bases__ static string could get a MemoryError
* 1. getattr(cls, '__bases__') could raise an AttributeError
* 2. getattr(cls, '__bases__') could raise some other exception
* 3. getattr(cls, '__bases__') could return a tuple
* 4. getattr(cls, '__bases__') could return something other than a tuple
*
* Only state #3 is a non-error state and only it returns a non-NULL object
* (it returns the retrieved tuple).
*
* Any raised AttributeErrors are masked by clearing the exception and
* returning NULL. If an object other than a tuple comes out of __bases__,
* then again, the return value is NULL. So yes, these two situations
* produce exactly the same results: NULL is returned and no error is set.
*
* If some exception other than AttributeError is raised, then NULL is also
* returned, but the exception is not cleared. That's because we want the
* exception to be propagated along.
*
* Callers are expected to test for PyErr_Occurred() when the return value
* is NULL to decide whether a valid exception should be propagated or not.
* When there's no exception to propagate, it's customary for the caller to
* set a TypeError.
*/
static PyObject *
abstract_get_bases(PyObject *cls)
{
static PyObject *__bases__ = NULL;
PyObject *bases;
if (__bases__ == NULL) {
__bases__ = PyString_FromString("__bases__");
if (__bases__ == NULL)
return NULL;
}
bases = PyObject_GetAttr(cls, __bases__);
if (bases == NULL) {
if (PyErr_ExceptionMatches(PyExc_AttributeError))
PyErr_Clear();
return NULL;
}
if (!PyTuple_Check(bases)) {
Py_DECREF(bases);
return NULL;
}
return bases;
}
static int
abstract_issubclass(PyObject *derived, PyObject *cls)
{
PyObject *bases;
Py_ssize_t i, n;
int r = 0;
if (derived == cls)
return 1;
if (PyTuple_Check(cls)) {
/* Not a general sequence -- that opens up the road to
recursion and stack overflow. */
n = PyTuple_GET_SIZE(cls);
for (i = 0; i < n; i++) {
if (derived == PyTuple_GET_ITEM(cls, i))
return 1;
}
}
bases = abstract_get_bases(derived);
if (bases == NULL) {
if (PyErr_Occurred())
return -1;
return 0;
}
n = PyTuple_GET_SIZE(bases);
for (i = 0; i < n; i++) {
r = abstract_issubclass(PyTuple_GET_ITEM(bases, i), cls);
if (r != 0)
break;
}
Py_DECREF(bases);
return r;
}
static int
check_class(PyObject *cls, const char *error)
{
PyObject *bases = abstract_get_bases(cls);
if (bases == NULL) {
/* Do not mask errors. */
if (!PyErr_Occurred())
PyErr_SetString(PyExc_TypeError, error);
return 0;
}
Py_DECREF(bases);
return -1;
}
static int
recursive_isinstance(PyObject *inst, PyObject *cls, int recursion_depth)
{
PyObject *icls;
static PyObject *__class__ = NULL;
int retval = 0;
if (__class__ == NULL) {
__class__ = PyString_FromString("__class__");
if (__class__ == NULL)
return -1;
}
if (PyClass_Check(cls) && PyInstance_Check(inst)) {
PyObject *inclass =
(PyObject*)((PyInstanceObject*)inst)->in_class;
retval = PyClass_IsSubclass(inclass, cls);
}
else if (PyType_Check(cls)) {
retval = PyObject_TypeCheck(inst, (PyTypeObject *)cls);
if (retval == 0) {
PyObject *c = PyObject_GetAttr(inst, __class__);
if (c == NULL) {
PyErr_Clear();
}
else {
if (c != (PyObject *)(inst->ob_type) &&
PyType_Check(c))
retval = PyType_IsSubtype(
(PyTypeObject *)c,
(PyTypeObject *)cls);
Py_DECREF(c);
}
}
}
else if (PyTuple_Check(cls)) {
Py_ssize_t i, n;
if (!recursion_depth) {
PyErr_SetString(PyExc_RuntimeError,
"nest level of tuple too deep");
return -1;
}
n = PyTuple_GET_SIZE(cls);
for (i = 0; i < n; i++) {
retval = recursive_isinstance(
inst,
PyTuple_GET_ITEM(cls, i),
recursion_depth-1);
if (retval != 0)
break;
}
}
else {
if (!check_class(cls,
"isinstance() arg 2 must be a class, type,"
" or tuple of classes and types"))
return -1;
icls = PyObject_GetAttr(inst, __class__);
if (icls == NULL) {
PyErr_Clear();
retval = 0;
}
else {
retval = abstract_issubclass(icls, cls);
Py_DECREF(icls);
}
}
static int
recursive_issubclass(PyObject *derived, PyObject *cls, int recursion_depth)
{
int retval;
if (!PyClass_Check(derived) || !PyClass_Check(cls)) {
if (!check_class(derived,
"issubclass() arg 1 must be a class"))
return -1;
if (PyTuple_Check(cls)) {
Py_ssize_t i;
Py_ssize_t n = PyTuple_GET_SIZE(cls);
if (!recursion_depth) {
PyErr_SetString(PyExc_RuntimeError,
"nest level of tuple too deep");
return -1;
}
for (i = 0; i < n; ++i) {
retval = recursive_issubclass(
derived,
PyTuple_GET_ITEM(cls, i),
recursion_depth-1);
if (retval != 0) {
/* either found it, or got an error */
return retval;
}
}
return 0;
}
else {
if (!check_class(cls,
"issubclass() arg 2 must be a class"
" or tuple of classes"))
return -1;
}
PyObject *
PyObject_GetIter(PyObject *o)
{
PyTypeObject *t = o->ob_type;
getiterfunc f = NULL;
if (PyType_HasFeature(t, Py_TPFLAGS_HAVE_ITER))
f = t->tp_iter;
if (f == NULL) {
if (PySequence_Check(o))
return PySeqIter_New(o);
return type_error("'%.200s' object is not iterable", o);
}
else {
PyObject *res = (*f)(o);
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;
}
}
/* Return next item.
* If an error occurs, return NULL. PyErr_Occurred() will be true.
* If the iteration terminates normally, return NULL and clear the
* PyExc_StopIteration exception (if it was set). PyErr_Occurred()
* will be false.
* Else return the next object. PyErr_Occurred() will be false.
*/
PyObject *
PyIter_Next(PyObject *iter)
{
PyObject *result;
assert(PyIter_Check(iter));
result = (*iter->ob_type->tp_iternext)(iter);
if (result == NULL &&
PyErr_Occurred() &&
PyErr_ExceptionMatches(PyExc_StopIteration))
PyErr_Clear();
return result;
}