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class A(object):
def __eq__(self,other):
print 'A'
class B(object):
def __eq__(self, other):
print 'B'
class C(object):
pass
a=A()
b=B()
c=C()
a==b
b==a
c==a
a==c
a=='123'
'123'==a
print '123'==c
print c=='123'
---------------------------------------------
A
B
A
A
A
A
False
False
def __eq__(self,other):
print 'A'
class B(object):
def __eq__(self, other):
print 'B'
class C(object):
pass
a=A()
b=B()
c=C()
a==b
b==a
c==a
a==c
a=='123'
'123'==a
print '123'==c
print c=='123'
---------------------------------------------
A
B
A
A
A
A
False
False
 | 1 mengzhuo May 28, 2014 请用gist python 的 eq实现，当左对象没有__eq__时，调用另一个的__eq__ |
 | 2 hahastudio May 28, 2014 可以看这里 http://eev.ee/blog/2012/03/24/python-faq-equality/ 就你结果来看，对于新类，== 是这么判断的 1. 左侧的类有没有自定义实现 __eq__？如果有，就调用left.__eq__(right) 2. 右侧的类有没有自定义实现 __eq__？如果有，就调用right.__eq__(left) 其实你可以试试C继承A，重写__eq__，a==c会print 'C'，根据blog，可以追加： 0. 右侧的类是左侧的类的子类，并且重写了__eq__，调用right.__eq__(left) 3. 都没有？尝试使用__cmp__重复上述过程 4. 尝试调用object.__eq__(a, b) |
 | 3 konakona May 31, 2014 用IDE格式化一下... |
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