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Guido van Rossum05311482001-04-20 21:06:46 +00001/* Iterator objects */
2
3#include "Python.h"
4
5typedef struct {
6 PyObject_HEAD
7 long it_index;
Guido van Rossum613bed32002-07-16 20:24:46 +00008 PyObject *it_seq; /* Set to NULL when iterator is exhausted */
Guido van Rossum213c7a62001-04-23 14:08:49 +00009} seqiterobject;
Guido van Rossum05311482001-04-20 21:06:46 +000010
11PyObject *
Guido van Rossum213c7a62001-04-23 14:08:49 +000012PySeqIter_New(PyObject *seq)
Guido van Rossum05311482001-04-20 21:06:46 +000013{
Guido van Rossum213c7a62001-04-23 14:08:49 +000014 seqiterobject *it;
Martin v. Löwis01f94bd2002-05-08 08:44:21 +000015
16 if (!PySequence_Check(seq)) {
17 PyErr_BadInternalCall();
18 return NULL;
19 }
Neil Schemenauerdbf409f2002-03-18 20:43:51 +000020 it = PyObject_GC_New(seqiterobject, &PySeqIter_Type);
Guido van Rossum05311482001-04-20 21:06:46 +000021 if (it == NULL)
22 return NULL;
23 it->it_index = 0;
24 Py_INCREF(seq);
25 it->it_seq = seq;
Neil Schemenauerdbf409f2002-03-18 20:43:51 +000026 _PyObject_GC_TRACK(it);
Guido van Rossum05311482001-04-20 21:06:46 +000027 return (PyObject *)it;
28}
Guido van Rossum613bed32002-07-16 20:24:46 +000029
Guido van Rossum05311482001-04-20 21:06:46 +000030static void
Guido van Rossum213c7a62001-04-23 14:08:49 +000031iter_dealloc(seqiterobject *it)
Guido van Rossum05311482001-04-20 21:06:46 +000032{
Neil Schemenauerdbf409f2002-03-18 20:43:51 +000033 _PyObject_GC_UNTRACK(it);
Guido van Rossum613bed32002-07-16 20:24:46 +000034 Py_XDECREF(it->it_seq);
Neil Schemenauerdbf409f2002-03-18 20:43:51 +000035 PyObject_GC_Del(it);
Guido van Rossum05311482001-04-20 21:06:46 +000036}
37
Neil Schemenauer7eac9b72001-07-12 13:27:25 +000038static int
39iter_traverse(seqiterobject *it, visitproc visit, void *arg)
40{
Thomas Wouters49fd7fa2006-04-21 10:40:58 +000041 Py_VISIT(it->it_seq);
42 return 0;
Neil Schemenauer7eac9b72001-07-12 13:27:25 +000043}
44
Guido van Rossum05311482001-04-20 21:06:46 +000045static PyObject *
Guido van Rossum213c7a62001-04-23 14:08:49 +000046iter_iternext(PyObject *iterator)
47{
48 seqiterobject *it;
49 PyObject *seq;
Raymond Hettinger48923c52002-08-09 01:30:17 +000050 PyObject *result;
Guido van Rossum213c7a62001-04-23 14:08:49 +000051
52 assert(PySeqIter_Check(iterator));
53 it = (seqiterobject *)iterator;
54 seq = it->it_seq;
Guido van Rossum613bed32002-07-16 20:24:46 +000055 if (seq == NULL)
56 return NULL;
Guido van Rossum213c7a62001-04-23 14:08:49 +000057
Raymond Hettinger48923c52002-08-09 01:30:17 +000058 result = PySequence_GetItem(seq, it->it_index);
59 if (result != NULL) {
60 it->it_index++;
61 return result;
62 }
63 if (PyErr_ExceptionMatches(PyExc_IndexError) ||
64 PyErr_ExceptionMatches(PyExc_StopIteration))
65 {
66 PyErr_Clear();
Guido van Rossum613bed32002-07-16 20:24:46 +000067 Py_DECREF(seq);
68 it->it_seq = NULL;
Martin v. Löwis01f94bd2002-05-08 08:44:21 +000069 }
Raymond Hettinger48923c52002-08-09 01:30:17 +000070 return NULL;
Guido van Rossum213c7a62001-04-23 14:08:49 +000071}
72
Raymond Hettinger6b27cda2005-09-24 21:23:05 +000073static PyObject *
Raymond Hettinger435bf582004-03-18 22:43:10 +000074iter_len(seqiterobject *it)
75{
Martin v. Löwis18e16552006-02-15 17:27:45 +000076 Py_ssize_t seqsize, len;
Raymond Hettinger7892b1c2004-04-12 18:10:01 +000077
78 if (it->it_seq) {
79 seqsize = PySequence_Size(it->it_seq);
80 if (seqsize == -1)
Raymond Hettinger6b27cda2005-09-24 21:23:05 +000081 return NULL;
Raymond Hettinger7892b1c2004-04-12 18:10:01 +000082 len = seqsize - it->it_index;
83 if (len >= 0)
Christian Heimes217cfd12007-12-02 14:31:20 +000084 return PyLong_FromSsize_t(len);
Raymond Hettinger7892b1c2004-04-12 18:10:01 +000085 }
Christian Heimes217cfd12007-12-02 14:31:20 +000086 return PyLong_FromLong(0);
Raymond Hettinger435bf582004-03-18 22:43:10 +000087}
88
Armin Rigof5b3e362006-02-11 21:32:43 +000089PyDoc_STRVAR(length_hint_doc, "Private method returning an estimate of len(list(it)).");
Raymond Hettinger6b27cda2005-09-24 21:23:05 +000090
91static PyMethodDef seqiter_methods[] = {
Armin Rigof5b3e362006-02-11 21:32:43 +000092 {"__length_hint__", (PyCFunction)iter_len, METH_NOARGS, length_hint_doc},
Raymond Hettinger6b27cda2005-09-24 21:23:05 +000093 {NULL, NULL} /* sentinel */
Raymond Hettinger435bf582004-03-18 22:43:10 +000094};
95
Guido van Rossum213c7a62001-04-23 14:08:49 +000096PyTypeObject PySeqIter_Type = {
Martin v. Löwis9f2e3462007-07-21 17:22:18 +000097 PyVarObject_HEAD_INIT(&PyType_Type, 0)
Guido van Rossum05311482001-04-20 21:06:46 +000098 "iterator", /* tp_name */
Neil Schemenauerdbf409f2002-03-18 20:43:51 +000099 sizeof(seqiterobject), /* tp_basicsize */
Guido van Rossum05311482001-04-20 21:06:46 +0000100 0, /* tp_itemsize */
101 /* methods */
102 (destructor)iter_dealloc, /* tp_dealloc */
103 0, /* tp_print */
Tim Peters6d6c1a32001-08-02 04:15:00 +0000104 0, /* tp_getattr */
Guido van Rossum05311482001-04-20 21:06:46 +0000105 0, /* tp_setattr */
106 0, /* tp_compare */
107 0, /* tp_repr */
108 0, /* tp_as_number */
Raymond Hettinger6b27cda2005-09-24 21:23:05 +0000109 0, /* tp_as_sequence */
Guido van Rossum05311482001-04-20 21:06:46 +0000110 0, /* tp_as_mapping */
111 0, /* tp_hash */
112 0, /* tp_call */
113 0, /* tp_str */
Tim Peters6d6c1a32001-08-02 04:15:00 +0000114 PyObject_GenericGetAttr, /* tp_getattro */
Guido van Rossum05311482001-04-20 21:06:46 +0000115 0, /* tp_setattro */
116 0, /* tp_as_buffer */
Neil Schemenauerdbf409f2002-03-18 20:43:51 +0000117 Py_TPFLAGS_DEFAULT | Py_TPFLAGS_HAVE_GC,/* tp_flags */
Guido van Rossum05311482001-04-20 21:06:46 +0000118 0, /* tp_doc */
Neil Schemenauer7eac9b72001-07-12 13:27:25 +0000119 (traverseproc)iter_traverse, /* tp_traverse */
Guido van Rossum05311482001-04-20 21:06:46 +0000120 0, /* tp_clear */
121 0, /* tp_richcompare */
122 0, /* tp_weaklistoffset */
Raymond Hettinger1da1dbf2003-03-17 19:46:11 +0000123 PyObject_SelfIter, /* tp_iter */
Thomas Wouters49fd7fa2006-04-21 10:40:58 +0000124 iter_iternext, /* tp_iternext */
Raymond Hettinger6b27cda2005-09-24 21:23:05 +0000125 seqiter_methods, /* tp_methods */
Tim Peters6d6c1a32001-08-02 04:15:00 +0000126 0, /* tp_members */
Guido van Rossum05311482001-04-20 21:06:46 +0000127};
128
129/* -------------------------------------- */
130
131typedef struct {
132 PyObject_HEAD
Guido van Rossum613bed32002-07-16 20:24:46 +0000133 PyObject *it_callable; /* Set to NULL when iterator is exhausted */
134 PyObject *it_sentinel; /* Set to NULL when iterator is exhausted */
Guido van Rossum05311482001-04-20 21:06:46 +0000135} calliterobject;
136
137PyObject *
138PyCallIter_New(PyObject *callable, PyObject *sentinel)
139{
140 calliterobject *it;
Neil Schemenauerdbf409f2002-03-18 20:43:51 +0000141 it = PyObject_GC_New(calliterobject, &PyCallIter_Type);
Guido van Rossum05311482001-04-20 21:06:46 +0000142 if (it == NULL)
143 return NULL;
144 Py_INCREF(callable);
145 it->it_callable = callable;
146 Py_INCREF(sentinel);
147 it->it_sentinel = sentinel;
Neil Schemenauerdbf409f2002-03-18 20:43:51 +0000148 _PyObject_GC_TRACK(it);
Guido van Rossum05311482001-04-20 21:06:46 +0000149 return (PyObject *)it;
150}
151static void
152calliter_dealloc(calliterobject *it)
153{
Neil Schemenauerdbf409f2002-03-18 20:43:51 +0000154 _PyObject_GC_UNTRACK(it);
Guido van Rossum613bed32002-07-16 20:24:46 +0000155 Py_XDECREF(it->it_callable);
156 Py_XDECREF(it->it_sentinel);
Neil Schemenauerdbf409f2002-03-18 20:43:51 +0000157 PyObject_GC_Del(it);
Guido van Rossum05311482001-04-20 21:06:46 +0000158}
Guido van Rossum213c7a62001-04-23 14:08:49 +0000159
Neil Schemenauer7eac9b72001-07-12 13:27:25 +0000160static int
161calliter_traverse(calliterobject *it, visitproc visit, void *arg)
162{
Thomas Wouters49fd7fa2006-04-21 10:40:58 +0000163 Py_VISIT(it->it_callable);
164 Py_VISIT(it->it_sentinel);
Neil Schemenauer7eac9b72001-07-12 13:27:25 +0000165 return 0;
166}
167
Guido van Rossum05311482001-04-20 21:06:46 +0000168static PyObject *
Guido van Rossum213c7a62001-04-23 14:08:49 +0000169calliter_iternext(calliterobject *it)
170{
Guido van Rossum613bed32002-07-16 20:24:46 +0000171 if (it->it_callable != NULL) {
Guido van Rossum84b2bed2002-08-16 17:01:09 +0000172 PyObject *args = PyTuple_New(0);
173 PyObject *result;
174 if (args == NULL)
175 return NULL;
176 result = PyObject_Call(it->it_callable, args, NULL);
177 Py_DECREF(args);
Guido van Rossum613bed32002-07-16 20:24:46 +0000178 if (result != NULL) {
179 int ok;
180 ok = PyObject_RichCompareBool(result,
181 it->it_sentinel,
182 Py_EQ);
183 if (ok == 0)
184 return result; /* Common case, fast path */
Guido van Rossum213c7a62001-04-23 14:08:49 +0000185 Py_DECREF(result);
Guido van Rossum613bed32002-07-16 20:24:46 +0000186 if (ok > 0) {
Raymond Hettinger75ccea32004-09-01 07:02:44 +0000187 Py_CLEAR(it->it_callable);
188 Py_CLEAR(it->it_sentinel);
Guido van Rossum613bed32002-07-16 20:24:46 +0000189 }
190 }
191 else if (PyErr_ExceptionMatches(PyExc_StopIteration)) {
192 PyErr_Clear();
Raymond Hettinger75ccea32004-09-01 07:02:44 +0000193 Py_CLEAR(it->it_callable);
194 Py_CLEAR(it->it_sentinel);
Guido van Rossum213c7a62001-04-23 14:08:49 +0000195 }
196 }
Guido van Rossum613bed32002-07-16 20:24:46 +0000197 return NULL;
Guido van Rossum213c7a62001-04-23 14:08:49 +0000198}
199
Guido van Rossum05311482001-04-20 21:06:46 +0000200PyTypeObject PyCallIter_Type = {
Martin v. Löwis9f2e3462007-07-21 17:22:18 +0000201 PyVarObject_HEAD_INIT(&PyType_Type, 0)
Christian Heimesa22e8bd2007-11-29 22:35:39 +0000202 "callable_iterator", /* tp_name */
Neil Schemenauerdbf409f2002-03-18 20:43:51 +0000203 sizeof(calliterobject), /* tp_basicsize */
Guido van Rossum05311482001-04-20 21:06:46 +0000204 0, /* tp_itemsize */
205 /* methods */
206 (destructor)calliter_dealloc, /* tp_dealloc */
207 0, /* tp_print */
Tim Peters6d6c1a32001-08-02 04:15:00 +0000208 0, /* tp_getattr */
Guido van Rossum05311482001-04-20 21:06:46 +0000209 0, /* tp_setattr */
210 0, /* tp_compare */
211 0, /* tp_repr */
212 0, /* tp_as_number */
213 0, /* tp_as_sequence */
214 0, /* tp_as_mapping */
215 0, /* tp_hash */
216 0, /* tp_call */
217 0, /* tp_str */
Tim Peters6d6c1a32001-08-02 04:15:00 +0000218 PyObject_GenericGetAttr, /* tp_getattro */
Guido van Rossum05311482001-04-20 21:06:46 +0000219 0, /* tp_setattro */
220 0, /* tp_as_buffer */
Neil Schemenauerdbf409f2002-03-18 20:43:51 +0000221 Py_TPFLAGS_DEFAULT | Py_TPFLAGS_HAVE_GC,/* tp_flags */
Walter Dörwald03f6c542003-06-25 13:12:18 +0000222 0, /* tp_doc */
223 (traverseproc)calliter_traverse, /* tp_traverse */
224 0, /* tp_clear */
Guido van Rossum05311482001-04-20 21:06:46 +0000225 0, /* tp_richcompare */
226 0, /* tp_weaklistoffset */
Raymond Hettinger1da1dbf2003-03-17 19:46:11 +0000227 PyObject_SelfIter, /* tp_iter */
Guido van Rossum213c7a62001-04-23 14:08:49 +0000228 (iternextfunc)calliter_iternext, /* tp_iternext */
Guido van Rossum613bed32002-07-16 20:24:46 +0000229 0, /* tp_methods */
Guido van Rossum05311482001-04-20 21:06:46 +0000230};
Guido van Rossumb65fb332006-08-25 23:26:40 +0000231
232