cpython/Doc/c-api/slice.rst

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.. highlightlang:: c
.. _slice-objects:
Slice Objects
-------------
.. cvar:: PyTypeObject PySlice_Type
.. index:: single: SliceType (in module types)
The type object for slice objects. This is the same as ``slice`` and
``types.SliceType``.
.. cfunction:: int PySlice_Check(PyObject *ob)
Return true if *ob* is a slice object; *ob* must not be *NULL*.
.. cfunction:: PyObject* PySlice_New(PyObject *start, PyObject *stop, PyObject *step)
Return a new slice object with the given values. The *start*, *stop*, and
*step* parameters are used as the values of the slice object attributes of the
same names. Any of the values may be *NULL*, in which case the ``None`` will be
used for the corresponding attribute. Return *NULL* if the new object could not
be allocated.
.. cfunction:: int PySlice_GetIndices(PySliceObject *slice, Py_ssize_t length, Py_ssize_t *start, Py_ssize_t *stop, Py_ssize_t *step)
Retrieve the start, stop and step indices from the slice object *slice*,
assuming a sequence of length *length*. Treats indices greater than *length* as
errors.
Returns 0 on success and -1 on error with no exception set (unless one of the
indices was not :const:`None` and failed to be converted to an integer, in which
case -1 is returned with an exception set).
You probably do not want to use this function.
.. cfunction:: 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)
Usable replacement for :cfunc:`PySlice_GetIndices`. Retrieve the start, stop,
and step indices from the slice object *slice* assuming a sequence of length
*length*, and store the length of the slice in *slicelength*. Out of bounds
indices are clipped in a manner consistent with the handling of normal slices.
Returns 0 on success and -1 on error with exception set.