擅长:python、mysql、java
<p>它为<code>except</code>块内的异常提供变量名:</p>
<pre><code>>>> try:
... raise Exception('foo')
... except Exception, ex:
... print ex
... print type(ex)
...
foo
<type 'exceptions.Exception'>
</code></pre>
<p>我个人觉得<code>as</code>语法更清晰:</p>
^{pr2}$
<p>但是根据<a href="https://stackoverflow.com/questions/2535760/python-try-except-comma-vs-as-in-except">this question</a>中的答案,as语法直到2.6才被引入。在</p>