python Class: 面向对象高级编程 __iter__ 和 next()

官网解释：

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.

也就是说 __iter__与next()是配套使用的。

Fibonacci数列：

#!/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

运行失败：

怎么用class做才能成功呢？？？？？

后来，才发现，我2.7版本的解释器不支持，用网页上的Python3在线编程解释器完美运行。。。。。。is ri le gou le.

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

请问各位大佬，在2.7版本中我该怎么使用 __iter__ 呢？？求教！！！

原文地址：http://blog.51cto.com/13502993/2147531