Iterator Protocol

There are two functions specifically for working with iterators.

int PyIter_Check(PyObject *o)
Part of the Stable ABI since version 3.8.

Return non-zero if the object o can be safely passed to PyIter_NextItem() and 0 otherwise. This function always succeeds.

int PyAIter_Check(PyObject *o)
Part of the Stable ABI since version 3.10.

Return non-zero if the object o provides the AsyncIterator protocol, and 0 otherwise. This function always succeeds.

Added in version 3.10.

int PyIter_NextItem(PyObject *iter, PyObject **item)
Part of the Stable ABI since version 3.14.

Return 1 and set item to a strong reference of the next value of the iterator iter on success. Return 0 and set item to NULL if there are no remaining values. Return -1, set item to NULL and set an exception on error.

Added in version 3.14.

PyObject *PyIter_Next(PyObject *o)
Return value: New reference. Part of the Stable ABI.

This is an older version of PyIter_NextItem(), which is retained for backwards compatibility. Prefer PyIter_NextItem().

Return the next value from the iterator o. The object must be an iterator according to PyIter_Check() (it is up to the caller to check this). If there are no remaining values, returns NULL with no exception set. If an error occurs while retrieving the item, returns NULL and passes along the exception.

type PySendResult

The enum value used to represent different results of PyIter_Send().

Added in version 3.10.

PySendResult PyIter_Send(PyObject *iter, PyObject *arg, PyObject **presult)
Part of the Stable ABI since version 3.10.

Sends the arg value into the iterator iter. Returns:

  • PYGEN_RETURN if iterator returns. Return value is returned via presult.

  • PYGEN_NEXT if iterator yields. Yielded value is returned via presult.

  • PYGEN_ERROR if iterator has raised and exception. presult is set to NULL.

Added in version 3.10.