56    start, stop, and step are python objects with None indicating no
61 PySlice_New(PyObject *start, PyObject *stop, PyObject *step)  in PySlice_New()  argument
70     if (start == NULL) start = Py_None;  in PySlice_New()
71     Py_INCREF(start);  in PySlice_New()
76     obj->start = start;  in PySlice_New()
86     PyObject *start, *end, *slice;  in _PySlice_FromIndices()  local
87     start = PyInt_FromSsize_t(istart);  in _PySlice_FromIndices()
88     if (!start)  in _PySlice_FromIndices()
92         Py_DECREF(start);  in _PySlice_FromIndices()
96     slice = PySlice_New(start, end, NULL);  in _PySlice_FromIndices()
97     Py_DECREF(start);  in _PySlice_FromIndices()
104                    Py_ssize_t *start, Py_ssize_t *stop, Py_ssize_t *step)  in PySlice_GetIndices()  argument
113     if (r->start == Py_None) {  in PySlice_GetIndices()
114         *start = *step < 0 ? length-1 : 0;  in PySlice_GetIndices()
116         if (!_PyAnyInt_Check(r->start)) return -1;  in PySlice_GetIndices()
117         *start = PyInt_AsSsize_t(r->start);  in PySlice_GetIndices()
118         if (*start < 0) *start += length;  in PySlice_GetIndices()
128     if (*start >= length) return -1;  in PySlice_GetIndices()
135                 Py_ssize_t *start, Py_ssize_t *stop, Py_ssize_t *step)  in _PySlice_Unpack()  argument
161     if (r->start == Py_None) {  in _PySlice_Unpack()
162         *start = *step < 0 ? PY_SSIZE_T_MAX : 0;  in _PySlice_Unpack()
165         if (!_PyEval_SliceIndex(r->start, start)) return -1;  in _PySlice_Unpack()
180                        Py_ssize_t *start, Py_ssize_t *stop, Py_ssize_t step)  in _PySlice_AdjustIndices()  argument
187     if (*start < 0) {  in _PySlice_AdjustIndices()
188         *start += length;  in _PySlice_AdjustIndices()
189         if (*start < 0) {  in _PySlice_AdjustIndices()
190             *start = (step < 0) ? -1 : 0;  in _PySlice_AdjustIndices()
193     else if (*start >= length) {  in _PySlice_AdjustIndices()
194         *start = (step < 0) ? length - 1 : length;  in _PySlice_AdjustIndices()
208         if (*stop < *start) {  in _PySlice_AdjustIndices()
209             return (*start - *stop - 1) / (-step) + 1;  in _PySlice_AdjustIndices()
213         if (*start < *stop) {  in _PySlice_AdjustIndices()
214             return (*stop - *start - 1) / step + 1;  in _PySlice_AdjustIndices()
224                      Py_ssize_t *start, Py_ssize_t *stop, Py_ssize_t *step,  in PySlice_GetIndicesEx()  argument
227     if (_PySlice_Unpack((PyObject *)r, start, stop, step) < 0)  in PySlice_GetIndicesEx()
229     *slicelength = _PySlice_AdjustIndices(length, start, stop, *step);  in PySlice_GetIndicesEx()
236     PyObject *start, *stop, *step;  in slice_new()  local
238     start = stop = step = NULL;  in slice_new()
243     if (!PyArg_UnpackTuple(args, "slice", 1, 3, &start, &stop, &step))  in slice_new()
246     /* This swapping of stop and start is to maintain similarity with  in slice_new()
249         stop = start;  in slice_new()
250         start = NULL;  in slice_new()
252     return PySlice_New(start, stop, step);  in slice_new()
257 slice(start, stop[, step])\n\
266     Py_DECREF(r->start);  in slice_dealloc()
278     PyString_ConcatAndDel(&s, PyObject_Repr(r->start));  in slice_repr()
289     {"start", T_OBJECT, offsetof(PySliceObject, start), READONLY},
298     Py_ssize_t ilen, start, stop, step;  in slice_indices()  local
306     if (_PySlice_Unpack((PyObject *)self, &start, &stop, &step) < 0) {  in slice_indices()
309     _PySlice_AdjustIndices(ilen, &start, &stop, step);  in slice_indices()
311     return Py_BuildValue("(nnn)", start, stop, step);  in slice_indices()
315 "S.indices(len) -> (start, stop, stride)\n\
317 Assuming a sequence of length len, calculate the start and stop\n\
325     return Py_BuildValue("O(OOO)", Py_TYPE(self), self->start, self->stop, self->step);  in slice_reduce()
346     if (PyObject_Cmp(v->start, w->start, &result) < 0)  in slice_compare()
369     Py_VISIT(v->start);  in slice_traverse()