6.3 Sequence Protocol

Python 2.5

previous page next page

6.3 Sequence Protocol

int PySequence_Check(PyObject *o)
Return 1 if the object provides sequence protocol, and 0 otherwise. This function always succeeds.

Py_ssize_t PySequence_Size(PyObject *o)
Returns the number of objects in sequence o on success, and -1 on failure. For objects that do not provide sequence protocol, this is equivalent to the Python expression "len(o)".

Py_ssize_t PySequence_Length(PyObject *o)
Alternate name for PySequence_Size().

PyObject* PySequence_Concat(PyObject *o1, PyObject *o2)
Return value: New reference.
Return the concatenation of o1 and o2 on success, and NULL on failure. This is the equivalent of the Python expression "o1 + o2".

PyObject* PySequence_Repeat(PyObject *o, Py_ssize_t count)
Return value: New reference.
Return the result of repeating sequence object o count times, or NULL on failure. This is the equivalent of the Python expression "o * count".

PyObject* PySequence_InPlaceConcat(PyObject *o1, PyObject *o2)
Return value: New reference.
Return the concatenation of o1 and o2 on success, and NULL on failure. The operation is done in-place when o1 supports it. This is the equivalent of the Python expression "o1 += o2".

PyObject* PySequence_InPlaceRepeat(PyObject *o, Py_ssize_t count)
Return value: New reference.
Return the result of repeating sequence object o count times, or NULL on failure. The operation is done in-place when o supports it. This is the equivalent of the Python expression "o *= count".

PyObject* PySequence_GetItem(PyObject *o, Py_ssize_t i)
Return value: New reference.
Return the ith element of o, or NULL on failure. This is the equivalent of the Python expression "o[i]".

PyObject* PySequence_GetSlice(PyObject *o, Py_ssize_t i1, Py_ssize_t i2)
Return value: New reference.
Return the slice of sequence object o between i1 and i2, or NULL on failure. This is the equivalent of the Python expression "o[i1:i2]".

int PySequence_SetItem(PyObject *o, Py_ssize_t i, PyObject *v)
Assign object v to the ith element of o. Returns -1 on failure. This is the equivalent of the Python statement "o[i] = v". This function does not steal a reference to v.

int PySequence_DelItem(PyObject *o, Py_ssize_t i)
Delete the ith element of object o. Returns -1 on failure. This is the equivalent of the Python statement "del o[i]".

int PySequence_SetSlice(PyObject *o, Py_ssize_t i1, Py_ssize_t i2, PyObject *v)
Assign the sequence object v to the slice in sequence object o from i1 to i2. This is the equivalent of the Python statement "o[i1:i2] = v".

int PySequence_DelSlice(PyObject *o, Py_ssize_t i1, Py_ssize_t i2)
Delete the slice in sequence object o from i1 to i2. Returns -1 on failure. This is the equivalent of the Python statement "del o[i1:i2]".

int PySequence_Count(PyObject *o, PyObject *value)
Return the number of occurrences of value in o, that is, return the number of keys for which o[key] == value. On failure, return -1. This is equivalent to the Python expression "o.count(value)".

int PySequence_Contains(PyObject *o, PyObject *value)
Determine if o contains value. If an item in o is equal to value, return 1, otherwise return 0. On error, return -1. This is equivalent to the Python expression "value in o".

int PySequence_Index(PyObject *o, PyObject *value)
Return the first index i for which o[i] == value. On error, return -1. This is equivalent to the Python expression "o.index(value)".

PyObject* PySequence_List(PyObject *o)
Return value: New reference.
Return a list object with the same contents as the arbitrary sequence o. The returned list is guaranteed to be new.

PyObject* PySequence_Tuple(PyObject *o)
Return value: New reference.
Return a tuple object with the same contents as the arbitrary sequence o or NULL on failure. If o is a tuple, a new reference will be returned, otherwise a tuple will be constructed with the appropriate contents. This is equivalent to the Python expression "tuple(o)".

PyObject* PySequence_Fast(PyObject *o, const char *m)
Return value: New reference.
Returns the sequence o as a tuple, unless it is already a tuple or list, in which case o is returned. Use PySequence_Fast_GET_ITEM() to access the members of the result. Returns NULL on failure. If the object is not a sequence, raises TypeError with m as the message text.

PyObject* PySequence_Fast_GET_ITEM(PyObject *o, Py_ssize_t i)
Return value: Borrowed reference.
Return the ith element of o, assuming that o was returned by PySequence_Fast(), o is not NULL, and that i is within bounds.

PyObject** PySequence_Fast_ITEMS(PyObject *o)
Return the underlying array of PyObject pointers. Assumes that o was returned by PySequence_Fast() and o is not NULL. New in version 2.4.

PyObject* PySequence_ITEM(PyObject *o, Py_ssize_t i)
Return value: New reference.
Return the ith element of o or NULL on failure. Macro form of PySequence_GetItem() but without checking that PySequence_Check(o) is true and without adjustment for negative indices. New in version 2.3.

int PySequence_Fast_GET_SIZE(PyObject *o)
Returns the length of o, assuming that o was returned by PySequence_Fast() and that o is not NULL. The size can also be gotten by calling PySequence_Size() on o, but PySequence_Fast_GET_SIZE() is faster because it can assume o is a list or tuple.

Up one Level Python/C API Reference Manual Contents Index
Previous: Up: 6. Abstract Objects Layer Next:
Release 2.5, documentation updated on 19th September, 2006.
See About this document... for information on suggesting changes.

previous page start next page