返回顶部

收藏

Add iterator behavior to your classes

更多
#Define a __iter__() method which returns an 
#object with a next() method. If the class defines next(), then __iter__() can just 
#return self:

class Reverse:
    'Iterator for looping over a sequence backwards'
    def __init__(self, data):
        self.data = data
        self.index = len(data)
    def __iter__(self):
        return self
    def next(self):
        if self.index == 0:
            raise StopIteration
        self.index = self.index - 1
        return self.data[self.index]

for char in Reverse('spam'):
     print char

标签:Python,Buildin,Function

收藏

0人收藏

支持

0

反对

0

发表评论