ref: 17ebe55031ae6945ad1f671b69267a672328e4b1
dir: /sys/src/cmd/python/Objects/iterobject.c/
/* Iterator objects */ #include "Python.h" typedef struct { PyObject_HEAD long it_index; PyObject *it_seq; /* Set to NULL when iterator is exhausted */ } seqiterobject; PyObject * PySeqIter_New(PyObject *seq) { seqiterobject *it; if (!PySequence_Check(seq)) { PyErr_BadInternalCall(); return NULL; } it = PyObject_GC_New(seqiterobject, &PySeqIter_Type); if (it == NULL) return NULL; it->it_index = 0; Py_INCREF(seq); it->it_seq = seq; _PyObject_GC_TRACK(it); return (PyObject *)it; } static void iter_dealloc(seqiterobject *it) { _PyObject_GC_UNTRACK(it); Py_XDECREF(it->it_seq); PyObject_GC_Del(it); } static int iter_traverse(seqiterobject *it, visitproc visit, void *arg) { Py_VISIT(it->it_seq); return 0; } static PyObject * iter_iternext(PyObject *iterator) { seqiterobject *it; PyObject *seq; PyObject *result; assert(PySeqIter_Check(iterator)); it = (seqiterobject *)iterator; seq = it->it_seq; if (seq == NULL) return NULL; result = PySequence_GetItem(seq, it->it_index); if (result != NULL) { it->it_index++; return result; } if (PyErr_ExceptionMatches(PyExc_IndexError) || PyErr_ExceptionMatches(PyExc_StopIteration)) { PyErr_Clear(); Py_DECREF(seq); it->it_seq = NULL; } return NULL; } static PyObject * iter_len(seqiterobject *it) { Py_ssize_t seqsize, len; if (it->it_seq) { seqsize = PySequence_Size(it->it_seq); if (seqsize == -1) return NULL; len = seqsize - it->it_index; if (len >= 0) return PyInt_FromSsize_t(len); } return PyInt_FromLong(0); } PyDoc_STRVAR(length_hint_doc, "Private method returning an estimate of len(list(it))."); static PyMethodDef seqiter_methods[] = { {"__length_hint__", (PyCFunction)iter_len, METH_NOARGS, length_hint_doc}, {NULL, NULL} /* sentinel */ }; PyTypeObject PySeqIter_Type = { PyObject_HEAD_INIT(&PyType_Type) 0, /* ob_size */ "iterator", /* tp_name */ sizeof(seqiterobject), /* tp_basicsize */ 0, /* tp_itemsize */ /* methods */ (destructor)iter_dealloc, /* tp_dealloc */ 0, /* tp_print */ 0, /* 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 */ PyObject_GenericGetAttr, /* tp_getattro */ 0, /* tp_setattro */ 0, /* tp_as_buffer */ Py_TPFLAGS_DEFAULT | Py_TPFLAGS_HAVE_GC,/* tp_flags */ 0, /* tp_doc */ (traverseproc)iter_traverse, /* tp_traverse */ 0, /* tp_clear */ 0, /* tp_richcompare */ 0, /* tp_weaklistoffset */ PyObject_SelfIter, /* tp_iter */ iter_iternext, /* tp_iternext */ seqiter_methods, /* tp_methods */ 0, /* tp_members */ }; /* -------------------------------------- */ typedef struct { PyObject_HEAD PyObject *it_callable; /* Set to NULL when iterator is exhausted */ PyObject *it_sentinel; /* Set to NULL when iterator is exhausted */ } calliterobject; PyObject * PyCallIter_New(PyObject *callable, PyObject *sentinel) { calliterobject *it; it = PyObject_GC_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_TRACK(it); return (PyObject *)it; } static void calliter_dealloc(calliterobject *it) { _PyObject_GC_UNTRACK(it); Py_XDECREF(it->it_callable); Py_XDECREF(it->it_sentinel); PyObject_GC_Del(it); } static int calliter_traverse(calliterobject *it, visitproc visit, void *arg) { Py_VISIT(it->it_callable); Py_VISIT(it->it_sentinel); return 0; } static PyObject * calliter_iternext(calliterobject *it) { if (it->it_callable != NULL) { PyObject *args = PyTuple_New(0); PyObject *result; if (args == NULL) return NULL; result = PyObject_Call(it->it_callable, args, NULL); Py_DECREF(args); if (result != NULL) { int ok; ok = PyObject_RichCompareBool(result, it->it_sentinel, Py_EQ); if (ok == 0) return result; /* Common case, fast path */ Py_DECREF(result); if (ok > 0) { Py_CLEAR(it->it_callable); Py_CLEAR(it->it_sentinel); } } else if (PyErr_ExceptionMatches(PyExc_StopIteration)) { PyErr_Clear(); Py_CLEAR(it->it_callable); Py_CLEAR(it->it_sentinel); } } return NULL; } PyTypeObject PyCallIter_Type = { PyObject_HEAD_INIT(&PyType_Type) 0, /* ob_size */ "callable-iterator", /* tp_name */ sizeof(calliterobject), /* tp_basicsize */ 0, /* tp_itemsize */ /* methods */ (destructor)calliter_dealloc, /* tp_dealloc */ 0, /* tp_print */ 0, /* 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 */ PyObject_GenericGetAttr, /* tp_getattro */ 0, /* tp_setattro */ 0, /* tp_as_buffer */ Py_TPFLAGS_DEFAULT | Py_TPFLAGS_HAVE_GC,/* tp_flags */ 0, /* tp_doc */ (traverseproc)calliter_traverse, /* tp_traverse */ 0, /* tp_clear */ 0, /* tp_richcompare */ 0, /* tp_weaklistoffset */ PyObject_SelfIter, /* tp_iter */ (iternextfunc)calliter_iternext, /* tp_iternext */ 0, /* tp_methods */ };