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这是一个创建于 4405 天前的主题，其中的信息可能已经有所发展或是发生改变。
代码如下
#! /usr/bin/env python
_metaclass_ = type
class bird:
def _init_(self):
self.hungry = True
def eat(self):
if self.hungry:
print 'I am hungry'
self.hungry = False
else:
print 'No,thanks'
class Songbird(bird):
def _init_(self):
super(Songbird, self)._init_()
self.sound = 'Squawk!'
def sing(self):
print self.sound
a = Songbird()
a.sing()
a.eat()
a.eat()
错误信息：
Traceback (most recent call last):
File "bird.py", line 21, in <module>
a.sing()
File "bird.py", line 18, in sing
print self.sound
AttributeError: Songbird instance has no attribute 'sound'
#! /usr/bin/env python
_metaclass_ = type
class bird:
def _init_(self):
self.hungry = True
def eat(self):
if self.hungry:
print 'I am hungry'
self.hungry = False
else:
print 'No,thanks'
class Songbird(bird):
def _init_(self):
super(Songbird, self)._init_()
self.sound = 'Squawk!'
def sing(self):
print self.sound
a = Songbird()
a.sing()
a.eat()
a.eat()
错误信息：
Traceback (most recent call last):
File "bird.py", line 21, in <module>
a.sing()
File "bird.py", line 18, in sing
print self.sound
AttributeError: Songbird instance has no attribute 'sound'
 | 1 9hills 2013-09-21 14:54:47 +08:00  1 python里面 是__init__ 不是_init_ 两个下划线 |
 | 2 ybooty OP |
| 3 ybooty OP 把super(Songbird, self).__init__() 改为 bird.__init()的方法就可以成功，为什么前者就出问题.. |
| 4 ybooty OP 问题已经解决 |
| 5 9hills 2013-09-21 20:18:58 +08:00 @ybooty super() cannot be used with old-style class Python定义类有两种方法，调用父类初始化函数也有两种方法。 class A: 这是旧的定义方法 class A(object): 所有的类必须有父类，也就是bird类必须这么定义： class bird(object): 这是新的定义方法，只有新类型的类才能用super来init |
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