1 .. highlightlang:: c 2 3 .. _slice-objects: 4 5 Slice Objects 6 ------------- 7 8 9 .. c:var:: PyTypeObject PySlice_Type 10 11 .. index:: single: SliceType (in module types) 12 13 The type object for slice objects. This is the same as ``slice`` and 14 ``types.SliceType``. 15 16 17 .. c:function:: int PySlice_Check(PyObject *ob) 18 19 Return true if *ob* is a slice object; *ob* must not be *NULL*. 20 21 22 .. c:function:: PyObject* PySlice_New(PyObject *start, PyObject *stop, PyObject *step) 23 24 Return a new slice object with the given values. The *start*, *stop*, and 25 *step* parameters are used as the values of the slice object attributes of 26 the same names. Any of the values may be *NULL*, in which case the 27 ``None`` will be used for the corresponding attribute. Return *NULL* if 28 the new object could not be allocated. 29 30 31 .. c:function:: int PySlice_GetIndices(PySliceObject *slice, Py_ssize_t length, Py_ssize_t *start, Py_ssize_t *stop, Py_ssize_t *step) 32 33 Retrieve the start, stop and step indices from the slice object *slice*, 34 assuming a sequence of length *length*. Treats indices greater than 35 *length* as errors. 36 37 Returns ``0`` on success and ``-1`` on error with no exception set (unless one of 38 the indices was not :const:`None` and failed to be converted to an integer, 39 in which case ``-1`` is returned with an exception set). 40 41 You probably do not want to use this function. If you want to use slice 42 objects in versions of Python prior to 2.3, you would probably do well to 43 incorporate the source of :c:func:`PySlice_GetIndicesEx`, suitably renamed, 44 in the source of your extension. 45 46 .. versionchanged:: 2.5 47 This function used an :c:type:`int` type for *length* and an 48 :c:type:`int *` type for *start*, *stop*, and *step*. This might require 49 changes in your code for properly supporting 64-bit systems. 50 51 52 .. c:function:: int PySlice_GetIndicesEx(PySliceObject *slice, Py_ssize_t length, Py_ssize_t *start, Py_ssize_t *stop, Py_ssize_t *step, Py_ssize_t *slicelength) 53 54 Usable replacement for :c:func:`PySlice_GetIndices`. Retrieve the start, 55 stop, and step indices from the slice object *slice* assuming a sequence of 56 length *length*, and store the length of the slice in *slicelength*. Out 57 of bounds indices are clipped in a manner consistent with the handling of 58 normal slices. 59 60 Returns ``0`` on success and ``-1`` on error with exception set. 61 62 .. versionadded:: 2.3 63 64 .. versionchanged:: 2.5 65 This function used an :c:type:`int` type for *length* and an 66 :c:type:`int *` type for *start*, *stop*, *step*, and *slicelength*. This 67 might require changes in your code for properly supporting 64-bit 68 systems. 69 70 71 Ellipsis Object 72 --------------- 73 74 75 .. c:var:: PyObject *Py_Ellipsis 76 77 The Python ``Ellipsis`` object. This object has no methods. It needs to be 78 treated just like any other object with respect to reference counts. Like 79 :c:data:`Py_None` it is a singleton object. 80
