Iterator Protocol

Python documentation

There are two functions specifically for working with iterators.

intPyIter_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_Next()

, and 0 otherwise. This function always succeeds.

intPyAIter_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.

New in version 3.10.

PyObject

*PyIter_Next(

PyObject

*o)

Return value: New reference. Part of the

Stable ABI

.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.

To write a loop which iterates over an iterator, the C code should look something like this:

PyObject*iterator=PyObject_GetIter(obj);PyObject*item;if(iterator==NULL){/* propagate error */}while((item=PyIter_Next(iterator))){/* do something with item */.../* release reference when done */Py_DECREF(item);}Py_DECREF(iterator);if(PyErr_Occurred()){/* propagate error */}else{/* continue doing useful work */}typePySendResult

The enum value used to represent different results of

PyIter_Send()

.

New 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.

New in version 3.10.