问题

You want to write C extension code that consumes items from any iterable object suchas a list, tuple, file, or generator.

解决方案

Here is a sample C extension function that shows how to consume the items on aniterable:

static PyObject *py_consume_iterable(PyObject *self, PyObject *args) {
PyObject *obj;PyObject *iter;PyObject *item;

if (!PyArg_ParseTuple(args, “O”, &obj)) {return NULL;
}if ((iter = PyObject_GetIter(obj)) == NULL) {

return NULL;

}while ((item = PyIter_Next(iter)) != NULL) {

/ Use item [](#)/...Py_DECREF(item);

}

Py_DECREF(iter);return Py_BuildValue(“”);

}

讨论

The code in this recipe mirrors similar code in Python. The PyObject_GetIter() callis the same as calling iter() to get an iterator. The PyIter_Next() function invokesthe next method on the iterator returning the next item or NULL if there are no moreitems. Make sure you’re careful with memory management—Py_DECREF() needs to becalled on both the produced items and the iterator object itself to avoid leaking memory.