擅长:python、mysql、java
<p>当<strong>pdb调试器在计算return命令后停止时,它是函数调用的<strong>返回值</strong>。对于有任何副作用的返回表达式来说,Is是非常重要的(它不能像从管道中读取一行一样被复制)。在</p>
<pre><code>(Pdb) ... # stop somewhere in the debugger ...
> test.py(3)f()
-> return x + 1
(Pdb) l # list source: I'm just before return
1 def f():
2 x = 7
3 -> return x + 1
(Pdb) '__return__' in locals() # __return__ is still undefined
False
(Pdb) s
Return
> test.py(3)f()->8 # This printed 8 is a simple case, but frequently
(Pdb) '__return__' in locals() # the value is an object or line shortened to 80 ch.
True # __return__ has the value after return
(Pdb) __return__
8
</code></pre>
<p>如果函数退出时没有执行<em>return</em>命令,那么每次都是<code>__return__ == None</code>。在</p>