python过滤字符串中不属于指定集合中字符的类实例

python过滤字符串中不属于指定集合中字符的类实例_编程语言综合

2015-07-03 09:30:01 [小大] 已经帮助：人解决问题

　　本文实例讲述了python过滤字符串中不属于指定集合中字符的类。分享给大家供大家参考。具体如下：

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

import sets

class Keeper(object):

def __init__(self, keep):

self.keep = sets.Set(map(ord, keep))

def __getitem__(self, n):

if n not in self.keep:

return None

return unichr(n)

def __call__(self, s):

return s.translate(self)

makefilter = Keeper

if __name__ == '__main__':

just_vowels = makefilter('aeiouy')

print just_vowels(u'four score and seven years ago')

# 输出: ouoeaeeyeaao

print just_vowels(u'tiger, tiger burning bright')

# 输出: ieieuii

　　希望本文所述对大家的Python程序设计有所帮助。