Protocolo iterador

Hay dos funciones específicas para trabajar con iteradores.

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_Next(), 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.

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.

Para escribir un bucle que itera sobre un iterador, el código en C debería verse así:

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 */
}

type PySendResult

El valor de enumeración utilizado para representar diferentes resultados de 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.

Envía el valor arg al iterador iter. Retorna:

• PYGEN_RETURN si el iterador regresa. El valor de retorno se retorna a través de presult.

• PYGEN_NEXT si el iterador cede. El valor cedido se retorna a través de presult.

• PYGEN_ERROR si el iterador ha lanzado una excepción. presult se establece en NULL.

Added in version 3.10.