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Code: Alles auswählen

>>> class Player(object):
    def __init__(self, x):
        self.x = x
    def __cmp__(self, other):
        return self.x != other.x

    
>>> a = Player("Peter")
>>> b = Player("Pan")
>>> c = Player("Peter")
>>> a == a
True
>>> a == b
False
>>> a == c
True
>>> b == c
False
>>> b == a
False
>>> b == b
True
>>> v = {}
>>> v[a] = 0
>>> v[b] = 1
>>> v[c] = 2
>>> v
{<__main__.Player object at 0x011DB410>: 0, <__main__.Player object at 0x011DB450>: 1, <__main__.Player object at 0x011CCBF0>: 2}
>>> v[Player("Peter")]

Traceback (most recent call last):
  File "<pyshell#33>", line 1, in <module>
    v[Player("Peter")]
KeyError: <__main__.Player object at 0x011DB4D0>
>>> 

Code: Alles auswählen

>>> def hashText(text):
    h = 0
    for i, x in enumerate(text):
        h += (ord(x) + 1 << i)
    return h

>>> hashText("test")
1721
>>> hashText("tset")
1693
>>> class Player(object):
    def __init__(self, x):
        self.x = x
        self.h = hashText(x)
    def __cmp__(self, other):
        return self.x != other.x
    def __hash__(self):
        return self.h

    
>>> a = Player("Peter")
>>> b = Player("Pan")
>>> c = Player("Peter")
>>> a == a
True
>>> a == b
False
>>> a == c
True
>>> b == b
True
>>> v = {}
>>> v[a] = 0
>>> v[b] = 2
>>> v[c] = 1
>>> v
{<__main__.Player object at 0x011CC750>: 1, <__main__.Player object at 0x011CC410>: 2}
>>> v[Player("Peter")]
1

Code: Alles auswählen

>>> cmp(1,2)
-1
>>> cmp(1,1)
0
>>> cmp(2,1)
1