.. highlightlang:: c

Python provides two general-purpose iterator objects. The first, a sequence iterator, works with an arbitrary sequence supporting the :meth:`__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.

.. c:var:: PyTypeObject PySeqIter_Type

   Type object for iterator objects returned by :c:func:`PySeqIter_New` and the
   one-argument form of the :func:`iter` built-in function for built-in sequence
   types.

.. c:function:: int PySeqIter_Check(op)

   Return true if the type of *op* is :c:data:`PySeqIter_Type`.

.. c:function:: PyObject* PySeqIter_New(PyObject *seq)

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

.. c:var:: PyTypeObject PyCallIter_Type

   Type object for iterator objects returned by :c:func:`PyCallIter_New` and the
   two-argument form of the :func:`iter` built-in function.

.. c:function:: int PyCallIter_Check(op)

   Return true if the type of *op* is :c:data:`PyCallIter_Type`.

.. c:function:: PyObject* PyCallIter_New(PyObject *callable, PyObject *sentinel)

   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.