mirror of https://github.com/python/cpython
Mondo changes to the iterator stuff, without changing how Python code
sees it (test_iter.py is unchanged). - Added a tp_iternext slot, which calls the iterator's next() method; this is much faster for built-in iterators over built-in types such as lists and dicts, speeding up pybench's ForLoop with about 25% compared to Python 2.1. (Now there's a good argument for iterators. ;-) - Renamed the built-in sequence iterator SeqIter, affecting the C API functions for it. (This frees up the PyIter prefix for generic iterator operations.) - Added PyIter_Check(obj), which checks that obj's type has a tp_iternext slot and that the proper feature flag is set. - Added PyIter_Next(obj) which calls the tp_iternext slot. It has a somewhat complex return condition due to the need for speed: when it returns NULL, it may not have set an exception condition, meaning the iterator is exhausted; when the exception StopIteration is set (or a derived exception class), it means the same thing; any other exception means some other error occurred.
This commit is contained in:
Guido van Rossum
parent
8b3d6ca3df
commit
213c7a6aa5
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@ -470,11 +470,24 @@ xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx*/
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*/
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/* Iterators */
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DL_IMPORT(PyObject *) PyObject_GetIter(PyObject *);
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/* Takes an object and returns an iterator for it.
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This is typically a new iterator but if the argument
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is an iterator, this returns itself. */
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#define PyIter_Check(obj) \
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(PyType_HasFeature((obj)->ob_type, Py_TPFLAGS_HAVE_ITER) && \
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(obj)->ob_type->tp_iternext != NULL)
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DL_IMPORT(PyObject *) PyIter_Next(PyObject *);
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/* Takes an iterator object and calls its tp_iternext slot,
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returning the next value. If the iterator is exhausted,
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this can return NULL without setting an exception, *or*
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NULL with a StopIteration exception.
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NULL with any other exception means an error occurred. */
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/* Number Protocol:*/
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DL_IMPORT(int) PyNumber_Check(PyObject *o);
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@ -1,10 +1,10 @@
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/* Iterators (the basic kind, over a sequence) */
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extern DL_IMPORT(PyTypeObject) PyIter_Type;
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extern DL_IMPORT(PyTypeObject) PySeqIter_Type;
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#define PyIter_Check(op) ((op)->ob_type == &PyIter_Type)
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#define PySeqIter_Check(op) ((op)->ob_type == &PySeqIter_Type)
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extern DL_IMPORT(PyObject *) PyIter_New(PyObject *);
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extern DL_IMPORT(PyObject *) PySeqIter_New(PyObject *);
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extern DL_IMPORT(PyTypeObject) PyCallIter_Type;
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@ -201,6 +201,7 @@ typedef PyObject *(*reprfunc)(PyObject *);
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typedef long (*hashfunc)(PyObject *);
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typedef PyObject *(*richcmpfunc) (PyObject *, PyObject *, int);
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typedef PyObject *(*getiterfunc) (PyObject *);
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typedef PyObject *(*iternextfunc) (PyObject *);
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typedef struct _typeobject {
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PyObject_VAR_HEAD
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@ -252,6 +253,7 @@ typedef struct _typeobject {
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/* Iterators */
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getiterfunc tp_iter;
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iternextfunc tp_iternext;
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#ifdef COUNT_ALLOCS
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/* these must be last and never explicitly initialized */
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@ -1748,10 +1748,32 @@ PyObject_GetIter(PyObject *o)
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f = t->tp_iter;
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if (f == NULL) {
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if (PySequence_Check(o))
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return PyIter_New(o);
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return PySeqIter_New(o);
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PyErr_SetString(PyExc_TypeError, "iter() of non-sequence");
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return NULL;
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}
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else
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return (*f)(o);
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else {
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PyObject *res = (*f)(o);
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if (res != NULL && !PyIter_Check(res)) {
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PyErr_Format(PyExc_TypeError,
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"iter() returned non-iterator "
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"of type '%.100s'",
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res->ob_type->tp_name);
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Py_DECREF(res);
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res = NULL;
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}
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return res;
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}
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}
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PyObject *
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PyIter_Next(PyObject *iter)
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{
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if (!PyIter_Check(iter)) {
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PyErr_Format(PyExc_TypeError,
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"'%.100s' object is not an iterator",
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iter->ob_type->tp_name);
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return NULL;
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}
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return (*iter->ob_type->tp_iternext)(iter);
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}
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@ -848,7 +848,8 @@ instance_traverse(PyInstanceObject *o, visitproc visit, void *arg)
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return 0;
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}
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static PyObject *getitemstr, *setitemstr, *delitemstr, *lenstr, *iterstr;
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static PyObject *getitemstr, *setitemstr, *delitemstr, *lenstr;
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static PyObject *iterstr, *nextstr;
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static int
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instance_length(PyInstanceObject *inst)
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@ -1726,6 +1727,14 @@ instance_getiter(PyInstanceObject *self)
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if ((func = instance_getattr(self, iterstr)) != NULL) {
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PyObject *res = PyEval_CallObject(func, (PyObject *)NULL);
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Py_DECREF(func);
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if (res != NULL && !PyIter_Check(res)) {
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PyErr_Format(PyExc_TypeError,
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"__iter__ returned non-iterator "
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"of type '%.100s'",
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res->ob_type->tp_name);
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Py_DECREF(res);
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res = NULL;
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}
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return res;
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}
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PyErr_Clear();
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@ -1734,7 +1743,33 @@ instance_getiter(PyInstanceObject *self)
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return NULL;
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}
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Py_DECREF(func);
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return PyIter_New((PyObject *)self);
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return PySeqIter_New((PyObject *)self);
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}
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/* Call the iterator's next */
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static PyObject *
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instance_iternext(PyInstanceObject *self)
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{
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PyObject *func;
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if (nextstr == NULL)
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nextstr = PyString_InternFromString("next");
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if ((func = instance_getattr(self, nextstr)) != NULL) {
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PyObject *res = PyEval_CallObject(func, (PyObject *)NULL);
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Py_DECREF(func);
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if (res != NULL) {
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return res;
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}
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if (PyErr_ExceptionMatches(PyExc_StopIteration)) {
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PyErr_Clear();
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return NULL;
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}
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return NULL;
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}
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PyErr_SetString(PyExc_TypeError, "instance has no next() method");
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return NULL;
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}
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@ -1803,6 +1838,7 @@ PyTypeObject PyInstance_Type = {
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instance_richcompare, /* tp_richcompare */
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offsetof(PyInstanceObject, in_weakreflist), /* tp_weaklistoffset */
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(getiterfunc)instance_getiter, /* tp_iter */
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(iternextfunc)instance_iternext, /* tp_iternext */
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};
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@ -1354,6 +1354,7 @@ PyTypeObject PyDict_Type = {
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0, /* tp_richcompare */
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0, /* tp_weaklistoffset */
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(getiterfunc)dictiter_new, /* tp_iter */
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0, /* tp_iternext */
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};
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/* For backward compatibility with old dictionary interface */
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@ -1433,6 +1434,7 @@ static PyObject *
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dictiter_next(dictiterobject *di, PyObject *args)
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{
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PyObject *key;
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if (di->di_size != di->di_dict->ma_size) {
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PyErr_SetString(PyExc_RuntimeError,
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"dictionary changed size during iteration");
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@ -1460,9 +1462,25 @@ static PyMethodDef dictiter_methods[] = {
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};
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static PyObject *
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dictiter_getattr(dictiterobject *it, char *name)
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dictiter_getattr(dictiterobject *di, char *name)
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{
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return Py_FindMethod(dictiter_methods, (PyObject *)it, name);
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return Py_FindMethod(dictiter_methods, (PyObject *)di, name);
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}
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static PyObject *dictiter_iternext(dictiterobject *di)
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{
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PyObject *key;
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if (di->di_size != di->di_dict->ma_size) {
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PyErr_SetString(PyExc_RuntimeError,
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"dictionary changed size during iteration");
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return NULL;
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}
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if (PyDict_Next((PyObject *)(di->di_dict), &di->di_pos, &key, NULL)) {
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Py_INCREF(key);
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return key;
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}
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return NULL;
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}
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PyTypeObject PyDictIter_Type = {
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@ -1494,4 +1512,5 @@ PyTypeObject PyDictIter_Type = {
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0, /* tp_richcompare */
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0, /* tp_weaklistoffset */
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(getiterfunc)dictiter_getiter, /* tp_iter */
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(iternextfunc)dictiter_iternext, /* tp_iternext */
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};
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@ -1340,6 +1340,7 @@ PyTypeObject PyFile_Type = {
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0, /* tp_richcompare */
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0, /* tp_weaklistoffset */
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(getiterfunc)file_getiter, /* tp_iter */
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0, /* tp_iternext */
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};
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/* Interface for the 'soft space' between print items. */
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@ -6,13 +6,13 @@ typedef struct {
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PyObject_HEAD
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long it_index;
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PyObject *it_seq;
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} iterobject;
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} seqiterobject;
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PyObject *
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PyIter_New(PyObject *seq)
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PySeqIter_New(PyObject *seq)
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{
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iterobject *it;
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it = PyObject_NEW(iterobject, &PyIter_Type);
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seqiterobject *it;
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it = PyObject_NEW(seqiterobject, &PySeqIter_Type);
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if (it == NULL)
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return NULL;
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it->it_index = 0;
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@ -21,35 +21,21 @@ PyIter_New(PyObject *seq)
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return (PyObject *)it;
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}
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static void
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iter_dealloc(iterobject *it)
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iter_dealloc(seqiterobject *it)
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{
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Py_DECREF(it->it_seq);
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PyObject_DEL(it);
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}
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static PyObject *
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iter_next(iterobject *it, PyObject *args)
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iter_next(seqiterobject *it, PyObject *args)
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{
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PyObject *seq = it->it_seq;
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PyObject *result = PySequence_GetItem(seq, it->it_index++);
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if (PyList_Check(seq)) {
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PyObject *item;
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if (it->it_index >= PyList_GET_SIZE(seq)) {
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PyErr_SetObject(PyExc_StopIteration, Py_None);
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return NULL;
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}
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item = PyList_GET_ITEM(seq, it->it_index);
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it->it_index++;
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Py_INCREF(item);
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return item;
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}
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else {
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PyObject *result = PySequence_GetItem(seq, it->it_index++);
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if (result == NULL &&
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PyErr_ExceptionMatches(PyExc_IndexError))
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PyErr_SetObject(PyExc_StopIteration, Py_None);
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return result;
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}
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if (result == NULL && PyErr_ExceptionMatches(PyExc_IndexError))
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PyErr_SetObject(PyExc_StopIteration, Py_None);
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return result;
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}
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static PyObject *
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@ -59,6 +45,43 @@ iter_getiter(PyObject *it)
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return it;
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}
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/* Return (value, 0) if OK; (NULL, 0) at end; (NULL, -1) if exception */
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static PyObject *
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iter_iternext(PyObject *iterator)
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{
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seqiterobject *it;
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PyObject *seq;
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assert(PySeqIter_Check(iterator));
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it = (seqiterobject *)iterator;
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seq = it->it_seq;
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if (PyList_Check(seq)) {
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PyObject *item;
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if (it->it_index >= PyList_GET_SIZE(seq)) {
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return NULL;
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}
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item = PyList_GET_ITEM(seq, it->it_index);
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it->it_index++;
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Py_INCREF(item);
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return item;
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}
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else {
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PyObject *result = PySequence_GetItem(seq, it->it_index++);
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if (result != NULL) {
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return result;
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}
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if (PyErr_ExceptionMatches(PyExc_IndexError) ||
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PyErr_ExceptionMatches(PyExc_StopIteration)) {
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PyErr_Clear();
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return NULL;
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}
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else {
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return NULL;
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}
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}
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}
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static PyMethodDef iter_methods[] = {
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{"next", (PyCFunction)iter_next, METH_VARARGS,
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"it.next() -- get the next value, or raise StopIteration"},
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@ -66,16 +89,16 @@ static PyMethodDef iter_methods[] = {
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};
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static PyObject *
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iter_getattr(iterobject *it, char *name)
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iter_getattr(seqiterobject *it, char *name)
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{
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return Py_FindMethod(iter_methods, (PyObject *)it, name);
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}
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PyTypeObject PyIter_Type = {
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PyTypeObject PySeqIter_Type = {
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PyObject_HEAD_INIT(&PyType_Type)
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0, /* ob_size */
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"iterator", /* tp_name */
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sizeof(iterobject), /* tp_basicsize */
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sizeof(seqiterobject), /* tp_basicsize */
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0, /* tp_itemsize */
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/* methods */
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(destructor)iter_dealloc, /* tp_dealloc */
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@ -100,6 +123,7 @@ PyTypeObject PyIter_Type = {
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0, /* tp_richcompare */
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0, /* tp_weaklistoffset */
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(getiterfunc)iter_getiter, /* tp_iter */
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(iternextfunc)iter_iternext, /* tp_iternext */
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};
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/* -------------------------------------- */
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@ -130,6 +154,7 @@ calliter_dealloc(calliterobject *it)
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Py_DECREF(it->it_sentinel);
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PyObject_DEL(it);
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}
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static PyObject *
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calliter_next(calliterobject *it, PyObject *args)
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{
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@ -156,6 +181,22 @@ calliter_getattr(calliterobject *it, char *name)
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return Py_FindMethod(calliter_methods, (PyObject *)it, name);
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}
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static PyObject *
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calliter_iternext(calliterobject *it)
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{
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PyObject *result = PyObject_CallObject(it->it_callable, NULL);
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if (result != NULL) {
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if (PyObject_RichCompareBool(result, it->it_sentinel, Py_EQ)) {
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Py_DECREF(result);
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result = NULL;
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}
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}
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else if (PyErr_ExceptionMatches(PyExc_StopIteration)) {
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PyErr_Clear();
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}
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return result;
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}
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PyTypeObject PyCallIter_Type = {
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PyObject_HEAD_INIT(&PyType_Type)
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0, /* ob_size */
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@ -185,4 +226,5 @@ PyTypeObject PyCallIter_Type = {
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0, /* tp_richcompare */
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0, /* tp_weaklistoffset */
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(getiterfunc)iter_getiter, /* tp_iter */
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(iternextfunc)calliter_iternext, /* tp_iternext */
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};
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|
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|
@ -381,7 +381,6 @@ eval_code2(PyCodeObject *co, PyObject *globals, PyObject *locals,
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/* Make it easier to find out where we are with a debugger */
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char *filename = PyString_AsString(co->co_filename);
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#endif
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static PyObject *nextstr;
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/* Code access macros */
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||||
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||||
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|
@ -417,11 +416,6 @@ eval_code2(PyCodeObject *co, PyObject *globals, PyObject *locals,
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GETLOCAL(i) = value; } while (0)
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/* Start of code */
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if (nextstr == NULL) {
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nextstr = PyString_InternFromString("next");
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||||
if (nextstr == NULL)
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return NULL;
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}
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#ifdef USE_STACKCHECK
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if (tstate->recursion_depth%10 == 0 && PyOS_CheckStack()) {
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|
@ -1887,34 +1881,29 @@ eval_code2(PyCodeObject *co, PyObject *globals, PyObject *locals,
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x = PyObject_GetIter(v);
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Py_DECREF(v);
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if (x != NULL) {
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w = x;
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x = PyObject_GetAttr(w, nextstr);
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||||
Py_DECREF(w);
|
||||
if (x != NULL) {
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||||
PUSH(x);
|
||||
continue;
|
||||
}
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||||
PUSH(x);
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||||
continue;
|
||||
}
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||||
break;
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||||
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case FOR_ITER:
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||||
/* before: [iter]; after: [iter, iter()] *or* [] */
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||||
v = TOP();
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||||
x = PyObject_CallObject(v, NULL);
|
||||
if (x == NULL) {
|
||||
if (PyErr_ExceptionMatches(
|
||||
PyExc_StopIteration))
|
||||
{
|
||||
PyErr_Clear();
|
||||
x = v = POP();
|
||||
Py_DECREF(v);
|
||||
JUMPBY(oparg);
|
||||
continue;
|
||||
}
|
||||
break;
|
||||
x = PyIter_Next(v);
|
||||
if (x != NULL) {
|
||||
PUSH(x);
|
||||
continue;
|
||||
}
|
||||
PUSH(x);
|
||||
continue;
|
||||
if (!PyErr_Occurred() ||
|
||||
PyErr_ExceptionMatches(
|
||||
PyExc_StopIteration))
|
||||
{
|
||||
x = v = POP();
|
||||
Py_DECREF(v);
|
||||
JUMPBY(oparg);
|
||||
continue;
|
||||
}
|
||||
break;
|
||||
|
||||
case FOR_LOOP:
|
||||
/* for v in s: ...
|
||||
|
|
|
|||
Loading…
Reference in New Issue