Iterator Objects

Python provides two general-purpose iterator objects. The first, a sequence iterator, works with an arbitrary sequence supporting the __getitem__() method. The second works with a callable object and a sentinel value, calling the callable for each item in the sequence, and ending the iteration when the sentinel value is returned.

PyTypeObject PySeqIter_Type

Part of the Stable ABI.

Type object for iterator objects returned by PySeqIter_New() and the one-argument form of the iter() built-in function for built-in sequence types.

int PySeqIter_Check(PyObject *op)

Return true if the type of op is PySeqIter_Type. This function always succeeds.

PyObject *PySeqIter_New(PyObject *seq)

Return value: New reference. Part of the Stable ABI.

Return an iterator that works with a general sequence object, seq. The iteration ends when the sequence raises IndexError for the subscripting operation.

PyTypeObject PyCallIter_Type

Part of the Stable ABI.

Type object for iterator objects returned by PyCallIter_New() and the two-argument form of the iter() built-in function.

int PyCallIter_Check(PyObject *op)

Return true if the type of op is PyCallIter_Type. This function always succeeds.

PyObject *PyCallIter_New(PyObject *callable, PyObject *sentinel)

Return value: New reference. Part of the Stable ABI.

Return a new iterator. The first parameter, callable, can be any Python callable object that can be called with no parameters; each call to it should return the next item in the iteration. When callable returns a value equal to sentinel, the iteration will be terminated.

Range Objects

PyTypeObject PyRange_Type

Part of the Stable ABI.

The type object for range objects.

int PyRange_Check(PyObject *o)

Return true if the object o is an instance of a range object. This function always succeeds.

Builtin Iterator Types

These are built-in iteration types that are included in Python’s C API, but provide no additional functions. They are here for completeness.

C type	Python type
PyTypeObject PyEnum_Type Part of the Stable ABI.	enumerate
PyTypeObject PyFilter_Type Part of the Stable ABI.	filter
PyTypeObject PyMap_Type Part of the Stable ABI.	map
PyTypeObject PyReversed_Type Part of the Stable ABI.	reversed
PyTypeObject PyZip_Type Part of the Stable ABI.	zip

Other Iterator Objects

PyTypeObject PyByteArrayIter_Type

Part of the Stable ABI.

PyTypeObject PyBytesIter_Type

Part of the Stable ABI.

PyTypeObject PyListIter_Type

Part of the Stable ABI.

PyTypeObject PyListRevIter_Type

Part of the Stable ABI.

PyTypeObject PySetIter_Type

Part of the Stable ABI.

PyTypeObject PyTupleIter_Type

Part of the Stable ABI.

PyTypeObject PyRangeIter_Type

Part of the Stable ABI.

PyTypeObject PyLongRangeIter_Type

Part of the Stable ABI.

PyTypeObject PyDictIterKey_Type

Part of the Stable ABI.

PyTypeObject PyDictRevIterKey_Type

Part of the Stable ABI since version 3.8.

PyTypeObject PyDictIterValue_Type

Part of the Stable ABI.

PyTypeObject PyDictRevIterValue_Type

Part of the Stable ABI since version 3.8.

PyTypeObject PyDictIterItem_Type

Part of the Stable ABI.

PyTypeObject PyDictRevIterItem_Type

Part of the Stable ABI since version 3.8.

PyTypeObject PyODictIter_Type

Type objects for iterators of various built-in objects.

Do not create instances of these directly; prefer calling PyObject_GetIter() instead.

Note that there is no guarantee that a given built-in type uses a given iterator type. For example, iterating over range will use one of two iterator types depending on the size of the range. Other types may start using a similar scheme in the future, without warning.