cpython/Objects/iterobject.c

253 lines
5.7 KiB
C

/* Iterator objects */
#include "Python.h"
typedef struct {
PyObject_HEAD
long it_index;
PyObject *it_seq;
} seqiterobject;
PyObject *
PySeqIter_New(PyObject *seq)
{
seqiterobject *it;
it = PyObject_NEW(seqiterobject, &PySeqIter_Type);
if (it == NULL)
return NULL;
it->it_index = 0;
Py_INCREF(seq);
it->it_seq = seq;
PyObject_GC_Init(it);
return (PyObject *)it;
}
static void
iter_dealloc(seqiterobject *it)
{
PyObject_GC_Fini(it);
Py_DECREF(it->it_seq);
it = (seqiterobject *) PyObject_AS_GC(it);
PyObject_DEL(it);
}
static int
iter_traverse(seqiterobject *it, visitproc visit, void *arg)
{
return visit(it->it_seq, arg);
}
static PyObject *
iter_next(seqiterobject *it, PyObject *args)
{
PyObject *seq = it->it_seq;
PyObject *result = PySequence_GetItem(seq, it->it_index++);
if (result == NULL && PyErr_ExceptionMatches(PyExc_IndexError))
PyErr_SetObject(PyExc_StopIteration, Py_None);
return result;
}
static PyObject *
iter_getiter(PyObject *it)
{
Py_INCREF(it);
return it;
}
static PyObject *
iter_iternext(PyObject *iterator)
{
seqiterobject *it;
PyObject *seq;
assert(PySeqIter_Check(iterator));
it = (seqiterobject *)iterator;
seq = it->it_seq;
if (PyList_Check(seq)) {
PyObject *item;
if (it->it_index >= PyList_GET_SIZE(seq)) {
return NULL;
}
item = PyList_GET_ITEM(seq, it->it_index);
it->it_index++;
Py_INCREF(item);
return item;
}
else {
PyObject *result = PySequence_GetItem(seq, it->it_index++);
if (result != NULL) {
return result;
}
if (PyErr_ExceptionMatches(PyExc_IndexError) ||
PyErr_ExceptionMatches(PyExc_StopIteration)) {
PyErr_Clear();
return NULL;
}
else {
return NULL;
}
}
}
static PyMethodDef iter_methods[] = {
{"next", (PyCFunction)iter_next, METH_VARARGS,
"it.next() -- get the next value, or raise StopIteration"},
{NULL, NULL} /* sentinel */
};
static PyObject *
iter_getattr(seqiterobject *it, char *name)
{
return Py_FindMethod(iter_methods, (PyObject *)it, name);
}
PyTypeObject PySeqIter_Type = {
PyObject_HEAD_INIT(&PyType_Type)
0, /* ob_size */
"iterator", /* tp_name */
sizeof(seqiterobject) + PyGC_HEAD_SIZE, /* tp_basicsize */
0, /* tp_itemsize */
/* methods */
(destructor)iter_dealloc, /* tp_dealloc */
0, /* tp_print */
(getattrfunc)iter_getattr, /* tp_getattr */
0, /* tp_setattr */
0, /* tp_compare */
0, /* tp_repr */
0, /* tp_as_number */
0, /* tp_as_sequence */
0, /* tp_as_mapping */
0, /* tp_hash */
0, /* tp_call */
0, /* tp_str */
0, /* tp_getattro */
0, /* tp_setattro */
0, /* tp_as_buffer */
Py_TPFLAGS_DEFAULT | Py_TPFLAGS_GC, /* tp_flags */
0, /* tp_doc */
(traverseproc)iter_traverse, /* tp_traverse */
0, /* tp_clear */
0, /* tp_richcompare */
0, /* tp_weaklistoffset */
(getiterfunc)iter_getiter, /* tp_iter */
(iternextfunc)iter_iternext, /* tp_iternext */
};
/* -------------------------------------- */
typedef struct {
PyObject_HEAD
PyObject *it_callable;
PyObject *it_sentinel;
} calliterobject;
PyObject *
PyCallIter_New(PyObject *callable, PyObject *sentinel)
{
calliterobject *it;
it = PyObject_NEW(calliterobject, &PyCallIter_Type);
if (it == NULL)
return NULL;
Py_INCREF(callable);
it->it_callable = callable;
Py_INCREF(sentinel);
it->it_sentinel = sentinel;
PyObject_GC_Init(it);
return (PyObject *)it;
}
static void
calliter_dealloc(calliterobject *it)
{
PyObject_GC_Fini(it);
Py_DECREF(it->it_callable);
Py_DECREF(it->it_sentinel);
it = (calliterobject *) PyObject_AS_GC(it);
PyObject_DEL(it);
}
static int
calliter_traverse(calliterobject *it, visitproc visit, void *arg)
{
int err;
if ((err = visit(it->it_callable, arg)))
return err;
if ((err = visit(it->it_sentinel, arg)))
return err;
return 0;
}
static PyObject *
calliter_next(calliterobject *it, PyObject *args)
{
PyObject *result = PyObject_CallObject(it->it_callable, NULL);
if (result != NULL) {
if (PyObject_RichCompareBool(result, it->it_sentinel, Py_EQ)) {
PyErr_SetObject(PyExc_StopIteration, Py_None);
Py_DECREF(result);
result = NULL;
}
}
return result;
}
static PyMethodDef calliter_methods[] = {
{"next", (PyCFunction)calliter_next, METH_VARARGS,
"it.next() -- get the next value, or raise StopIteration"},
{NULL, NULL} /* sentinel */
};
static PyObject *
calliter_getattr(calliterobject *it, char *name)
{
return Py_FindMethod(calliter_methods, (PyObject *)it, name);
}
static PyObject *
calliter_iternext(calliterobject *it)
{
PyObject *result = PyObject_CallObject(it->it_callable, NULL);
if (result != NULL) {
if (PyObject_RichCompareBool(result, it->it_sentinel, Py_EQ)) {
Py_DECREF(result);
result = NULL;
}
}
else if (PyErr_ExceptionMatches(PyExc_StopIteration)) {
PyErr_Clear();
}
return result;
}
PyTypeObject PyCallIter_Type = {
PyObject_HEAD_INIT(&PyType_Type)
0, /* ob_size */
"callable-iterator", /* tp_name */
sizeof(calliterobject) + PyGC_HEAD_SIZE,/* tp_basicsize */
0, /* tp_itemsize */
/* methods */
(destructor)calliter_dealloc, /* tp_dealloc */
0, /* tp_print */
(getattrfunc)calliter_getattr, /* tp_getattr */
0, /* tp_setattr */
0, /* tp_compare */
0, /* tp_repr */
0, /* tp_as_number */
0, /* tp_as_sequence */
0, /* tp_as_mapping */
0, /* tp_hash */
0, /* tp_call */
0, /* tp_str */
0, /* tp_getattro */
0, /* tp_setattro */
0, /* tp_as_buffer */
Py_TPFLAGS_DEFAULT | Py_TPFLAGS_GC, /* tp_flags */
0, /* tp_doc */
(traverseproc)calliter_traverse, /* tp_traverse */
0, /* tp_clear */
0, /* tp_richcompare */
0, /* tp_weaklistoffset */
(getiterfunc)iter_getiter, /* tp_iter */
(iternextfunc)calliter_iternext, /* tp_iternext */
};