New in version 2.2.

• iterator.__iter__()

• Return the iterator object itself. This is required to allow both containers and iterators to be used with the for and instatements. This method corresponds to the tp_iter slot of the type structure for Python objects in the Python/C API.

• iterator.next()

• Return the next item from the container. If there are no further items, raise the

  StopIteration exception. This method corresponds to the tp_iternext slot of the type structure for Python objects in the Python/C API.

也就是說 __iter__與next()是配套使用的。

Fibonacci數列：

#!/usr/bin/python

# -*- coding: utf-8 -*-

class Fibo(object):

def __init__(self):

self.a, self.b = 0, 1

def __iter__(self):

return self

def __next__(self):

self.a, self.b = self.b, self.a + self.b

if self.a > 10000:

raise StopIteration()

return self.a, self.b

for n in Fibo():

print n

運行失敗：

怎麽用class做才能成功呢？？？？？

後來，才發現，我2.7版本的解釋器不支持，用網頁上的Python3在線編程解釋器完美運行。。。。。。is ri le gou le.

附使用的python3環境：http://www.dooccn.com/python3/

請問各位大佬，在2.7版本中我該怎麽使用 __iter__ 呢？？求教！！！

python Class: 面向對象高級編程 __iter__ 和 next()