擅长:python、mysql、java
<p>你可以将<code>list</code>子类化</p>
<pre><code>>>> class L(list):
... def append(self, item):
... list.append(self, item)
... if len(self) > 5: self[:1]=[]
...
>>> l = L()
>>> l.append('apple')
>>> l.append('orange')
>>> l.append('grape')
>>> l.append('banana')
>>> l.append('mango')
>>> print(l)
['apple', 'orange', 'grape', 'banana', 'mango']
>>> l.append('kiwi')
>>> print(l)
['orange', 'grape', 'banana', 'mango', 'kiwi']
>>>
</code></pre>