python Class：面向对象高级编程 __str__ / __repr__

其实：__str__ 与 __repr__效果一样， 人们说：__str__ 是面向用户的， 而__repr__是面向程序员的， 轰朵你？

官网解释：

• object.__repr__(self)?
• Called by the repr() built-in function and by string conversions (reverse
  quotes) to compute the “official” string representation of an object.  If at all
  possible, this should look like a valid Python expression that could be used to
  recreate an object with the same value (given an appropriate environment).  If
  this is not possible, a string of the form <...some useful description...>should be returned.  The return value must be a string object. If a class
  defines __repr__() but not __str__(), then __repr__() is also
  used when an “informal” string representation of instances of that class is
  required.

• object.__str__(self)?
• Called by the str() built-in function and by the printstatement to compute the “informal” string representation of an object.  This
  differs from __repr__() in that it does not have to be a valid Python
  expression: a more convenient or concise representation may be used instead.
  The return value must be a string object.

看了解释，哪里说是面向用户，哪里又说面向程序员了？？？？看到加粗字了没有，看到下滑线了没有？？？这里说的是作用于所有人好嘛！！！如果非要以自己的职位来说，好吧，好像是这么一回事，真是 淫秽  隐晦的表达。

不说了，先小试一下：

#!/usr/bin/python
# -*- coding: utf-8 -*-

class Student(object):
     def __init__(self, name):
         self.hah = name
        
class Str(Student):
     def __str__(self):
       return  'Str (name: %s)' %self.hah

class Repr(Student):
     def __repr__(self):
       return  'Repr(name: %s)' % self.hah

s = Student('Michael')
print s.hah

print Str('you')

print Repr('me')

最近非常的狂，不，不是最近，而是这个阶段的我，非常喜欢怼，如果我表达不好，那真是 抱歉了 。。。 你有理，你也来怼我啊，来啊，相互伤害啊！！！

原文地址：http://blog.51cto.com/13502993/2147376