blocks|key|1813430|text|堆栈回溯显示调用堆栈在程序运行过程中的某个点的状态。在实践中，当程序中出现错误时，您通常会遇到这些问题。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1813431|call+stack是堆栈帧的堆栈(或列表)。每个堆栈帧对应于一个子进程的调用(在Python中，是一个函数或列表理解)。堆栈是一种可以包含许多元素的数据结构，这些元素以后进先出(LIFO)的方式被删除。|offset|length|1813432|这在抽象上可能很难理解，但是通过一个例子它是相当简单的。|1813433|示例：|1813434|如果你有这个程序：|1813435|def+func1():
++++func2()

def+func2():
++++print("func2")|code-block|syntax|javascript|1813436|调用函数func1时，调用堆栈最初将包含func1的调用框架。然后，func1调用func2，后者将一个调用帧添加到堆栈。当func2退出时，相应的调用帧将从堆栈中删除，因此现在我们又回到了func1。当func1退出时，它的调用帧也会被移除，现在堆栈再次为空。|style|CODE|1813437|因此，我们将有以下堆栈跟踪：|1813438|[empty]+-->+func1+-->+func1+-->+func1+-->+[empty]
++++++++++++++++++++++func2|1813439|堆栈跟踪在调试中很有用，特别是在更复杂的示例中，因为它们显示了程序遇到错误时所在的位置。例如，如果我们修改func2，使其如下所示：|1813440|def+func2():
++++1+/+0|1813441|我们将获得一个具有以下堆栈回溯的ZeroDivisionError：|1813442|Traceback+(most+recent+call+last):
++File+"<stdin>",+line+1,+in+<module>
++File+"<stdin>",+line+2,+in+func1
++File+"<stdin>",+line+2,+in+func2
ZeroDivisionError:+division+by+zero|1813443|因此，我们可以看到错误发生在func2的第2行(在func1的第2行调用)。|1813444|entityMap|0|LINK|mutability|MUTABLE|url|https://en.wikipedia.org/wiki/Call_stack^0|0|0|A|0|0|0|0|0|0|4|5|K|5|Y|5|15|5|1Q|5|2N|5|2U|5|0|0|0|1H|5|0|0|G|H|0|0|E|5|P|5|0^^$0|@$1|2|3|4|5|6|7|1G|8|@]|9|@]|A|$]]|$1|B|3|C|5|6|7|1H|8|@]|9|@$D|1I|E|1J|1|1K]]|A|$]]|$1|F|3|G|5|6|7|1L|8|@]|9|@]|A|$]]|$1|H|3|I|5|6|7|1M|8|@]|9|@]|A|$]]|$1|J|3|K|5|6|7|1N|8|@]|9|@]|A|$]]|$1|L|3|M|5|N|7|1O|8|@]|9|@]|A|$O|P]]|$1|Q|3|R|5|6|7|1P|8|@$D|1Q|E|1R|S|T]|$D|1S|E|1T|S|T]|$D|1U|E|1V|S|T]|$D|1W|E|1X|S|T]|$D|1Y|E|1Z|S|T]|$D|20|E|21|S|T]|$D|22|E|23|S|T]]|9|@]|A|$]]|$1|U|3|V|5|6|7|24|8|@]|9|@]|A|$]]|$1|W|3|X|5|N|7|25|8|@]|9|@]|A|$O|P]]|$1|Y|3|Z|5|6|7|26|8|@$D|27|E|28|S|T]]|9|@]|A|$]]|$1|10|3|11|5|N|7|29|8|@]|9|@]|A|$O|P]]|$1|12|3|13|5|6|7|2A|8|@$D|2B|E|2C|S|T]]|9|@]|A|$]]|$1|14|3|15|5|N|7|2D|8|@]|9|@]|A|$O|P]]|$1|16|3|17|5|6|7|2E|8|@$D|2F|E|2G|S|T]|$D|2H|E|2I|S|T]]|9|@]|A|$]]|$1|18|3|-4|5|6|7|2J|8|@]|9|@]|A|$]]]|19|$1A|$5|1B|1C|1D|A|$1E|1F]]]]

The stack traceback displays the state of the call stack at a certain point in the running of a program. In practice, you'll usually encounter these when an error occurs in your program.

The <a href="https://en.wikipedia.org/wiki/Call_stack" rel="nofollow noreferrer">call stack</a> is a stack (or list) of stack frames. Each stack frame corresponds to the call of a subprocess (in Python, a function or [list]-comprehension). A stack is a data structure that can contain many elements, which are removed in last-in-first-out (LIFO) fashion.

This can be hard to understand in abstract, but with an example it's fairly simple.

Example:

If you have the program:

<pre class="lang-py prettyprint-override"><code>def func1():
 func2()

def func2():
 print("func2")
</code></pre>

And you call the function <code>func1</code>, the the call stack will initially contain a call frame for <code>func1</code>. Then <code>func1</code> calls <code>func2</code>, which adds a call frame to the stack. When <code>func2</code> exits, the corresponding call frame is removed from the stack, so now we're back in <code>func1</code>. When <code>func1</code> exits, its call frame is also removed and now the stack is empty again.

So we would have the following stack traces:

<pre><code>[empty] --&gt; func1 --&gt; func1 --&gt; func1 --&gt; [empty]
 func2
</code></pre>

Stack traces are useful in debugging, especially in more complex examples as they show where the program was when it encountered an error. For example, if we modify <code>func2</code> so that it looks like:

<pre class="lang-py prettyprint-override"><code>def func2():
 1 / 0
</code></pre>

We would get a <code>ZeroDivisionError</code> with the following stack traceback:

<pre><code>Traceback (most recent call last):
 File "&lt;stdin&gt;", line 1, in &lt;module&gt;
 File "&lt;stdin&gt;", line 2, in func1
 File "&lt;stdin&gt;", line 2, in func2
ZeroDivisionError: division by zero
</code></pre>

So we can see the error occurred in line 2 of <code>func2</code> (which was called on line 2 of <code>func1</code>).

I am very new with Python, I do still not understand what stack traceback in python is?
Could you explain it for me?
Thanks for your help very much!

What is stack traceback in python?

数据结构

Python

我是Python的新手，我仍然不明白python中的堆栈回溯是什么？你能给我解释一下吗？非常感谢你的帮助！

问python中的堆栈回溯是什么？
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