我正在尝试在已定义的同一函数内调用一个函数

Question

我正在尝试这样做：

def enter():
    print("hi")
    enter()

但是，一开始它给了我这个：

hi
hi
hi
hi
hi
hi
hi
hi
hi
hi
hi
hi
hi
hi
hi
hi
hi
hi
hi
hi
hi
hi
hi
hi
hi
hi
hi
hi
hi
hi
hi
hi
hi
hi
hi
hi
hi
hi
hi
hi
hi
hi
hi
hi
hi
hi
hi
hi
hi
hi
hi
hi
hi
hi
hi
hi
hi
hi
hi
hi
hi
hi
hi
hi
hi
hi
hi
hi
hi
hi
hi
hi
hi
hi
hi
hi
hi
hi
hi
hi
hi
hi
hi
hi
hi
hi
hi
hi
hi
hi
hi
hi
hi
hi
hi
hi
hi
hi
hi
hi
hi
hi
hi
hi
hi
hi
hi
hi
hi
hi
hi
hi
hi
hi
hi
hi
hi
hi
hi
hi
hi
hi
hi
hi
hi
hi
hi
hi
hi
hi
hi
hi
hi
hi
hi
hi
hi
hi
hi
hi
hi
hi
hi
hi
hi
hi
hi
hi
hi
hi
hi
hi
hi
hi
hi
hi
hi
hi
hi
hi
hi
hi
hi
hi

但是，在该数据流之后，它开始给我这样的错误：

Traceback (most recent call last):
  File "<pyshell#0>", line 1, in <module>
    enter()
  File "C:/Users/offcampus/AppData/Local/Programs/Python/Python35/len finder.py", line 11, in enter
    enter()
  File "C:/Users/offcampus/AppData/Local/Programs/Python/Python35/len finder.py", line 11, in enter
    enter()
  File "C:/Users/offcampus/AppData/Local/Programs/Python/Python35/len finder.py", line 11, in enter
    enter()
  File "C:/Users/offcampus/AppData/Local/Programs/Python/Python35/len finder.py", line 11, in enter
    enter()
  File "C:/Users/offcampus/AppData/Local/Programs/Python/Python35/len finder.py", line 11, in enter
    enter()
  File "C:/Users/offcampus/AppData/Local/Programs/Python/Python35/len finder.py", line 11, in enter
    enter()
  File "C:/Users/offcampus/AppData/Local/Programs/Python/Python35/len finder.py", line 11, in enter
    enter()
  File "C:/Users/offcampus/AppData/Local/Programs/Python/Python35/len finder.py", line 11, in enter
    enter()
  File "C:/Users/offcampus/AppData/Local/Programs/Python/Python35/len finder.py", line 11, in enter
    enter()
  File "C:/Users/offcampus/AppData/Local/Programs/Python/Python35/len finder.py", line 11, in enter
    enter()
  File "C:/Users/offcampus/AppData/Local/Programs/Python/Python35/len finder.py", line 11, in enter
    enter()
  File "C:/Users/offcampus/AppData/Local/Programs/Python/Python35/len finder.py", line 11, in enter
    enter()
  File "C:/Users/offcampus/AppData/Local/Programs/Python/Python35/len finder.py", line 11, in enter
    enter()
  File "C:/Users/offcampus/AppData/Local/Programs/Python/Python35/len finder.py", line 11, in enter
    enter()
  File "C:/Users/offcampus/AppData/Local/Programs/Python/Python35/len finder.py", line 11, in enter
    enter()
  File "C:/Users/offcampus/AppData/Local/Programs/Python/Python35/len finder.py", line 11, in enter
    enter()
  File "C:/Users/offcampus/AppData/Local/Programs/Python/Python35/len finder.py", line 11, in enter
    enter()
  File "C:/Users/offcampus/AppData/Local/Programs/Python/Python35/len finder.py", line 11, in enter
    enter()
  File "C:/Users/offcampus/AppData/Local/Programs/Python/Python35/len finder.py", line 11, in enter
    enter()
  File "C:/Users/offcampus/AppData/Local/Programs/Python/Python35/len finder.py", line 11, in enter
    enter()
  File "C:/Users/offcampus/AppData/Local/Programs/Python/Python35/len finder.py", line 11, in enter
    enter()
  File "C:/Users/offcampus/AppData/Local/Programs/Python/Python35/len finder.py", line 11, in enter
    enter()
  File "C:/Users/offcampus/AppData/Local/Programs/Python/Python35/len finder.py", line 11, in enter
    enter()
  File "C:/Users/offcampus/AppData/Local/Programs/Python/Python35/len finder.py", line 11, in enter
    enter()
  File "C:/Users/offcampus/AppData/Local/Programs/Python/Python35/len finder.py", line 11, in enter
    enter()
  File "C:/Users/offcampus/AppData/Local/Programs/Python/Python35/len finder.py", line 11, in enter
    enter()
  File "C:/Users/offcampus/AppData/Local/Programs/Python/Python35/len finder.py", line 11, in enter
    enter()
  File "C:/Users/offcampus/AppData/Local/Programs/Python/Python35/len finder.py", line 11, in enter
    enter()
  File "C:/Users/offcampus/AppData/Local/Programs/Python/Python35/len finder.py", line 11, in enter
    enter()
  File "C:/Users/offcampus/AppData/Local/Programs/Python/Python35/len finder.py", line 11, in enter
    enter()
  File "C:/Users/offcampus/AppData/Local/Programs/Python/Python35/len finder.py", line 11, in enter
    enter()
  File "C:/Users/offcampus/AppData/Local/Programs/Python/Python35/len finder.py", line 11, in enter
    enter()
  File "C:/Users/offcampus/AppData/Local/Programs/Python/Python35/len finder.py", line 11, in enter
    enter()
  File "C:/Users/offcampus/AppData/Local/Programs/Python/Python35/len finder.py", line 11, in enter
    enter()
  File "C:/Users/offcampus/AppData/Local/Programs/Python/Python35/len finder.py", line 11, in enter
    enter()
  File "C:/Users/offcampus/AppData/Local/Programs/Python/Python35/len finder.py", line 11, in enter
    enter()
  File "C:/Users/offcampus/AppData/Local/Programs/Python/Python35/len finder.py", line 11, in enter
    enter()
  File "C:/Users/offcampus/AppData/Local/Programs/Python/Python35/len finder.py", line 11, in enter
    enter()
  File "C:/Users/offcampus/AppData/Local/Programs/Python/Python35/len finder.py", line 11, in enter
    enter()
  File "C:/Users/offcampus/AppData/Local/Programs/Python/Python35/len finder.py", line 11, in enter
    enter()
  File "C:/Users/offcampus/AppData/Local/Programs/Python/Python35/len finder.py", line 11, in enter
    enter()
  File "C:/Users/offcampus/AppData/Local/Programs/Python/Python35/len finder.py", line 11, in enter

它说我已经达到最大深度的递归错误，谁能告诉我如何解决这个问题。

此外，如果有人告诉我递归错误甚至意味着什么，我将不胜感激。

提前致谢！！！

Answer 1

在函数内部调用函数称为递归，是循环的替代方法。但这是有代价的。 Python 需要 "remember" 之前对该函数的所有调用，而不是每次都重置的循环。因此，您可以理解为什么您的计算机最终会运行内存不足，因为您没有停止调用 enter。

这称为堆栈溢出——即，当计算机的 "stack"（内存）溢出（变得太高而有点崩溃）。其他较旧的语言，例如 C，根本无法很好地处理这个问题并且堆栈溢出有点成为程序员要处理的事情，（这就是为什么这被称为 whosebug.com -- 帮助他人解决他们的问题）。

为避免这种情况，Python 设置了递归的限制，超过此限制将引发错误（而不是破坏您的计算机）。为了防止您的代码达到这个（非常高的）限制，您需要指定一个 退出条件 。这是你 return 而不是再次递归的地方。这可以像 if 语句一样简单，也可以更复杂。这也是有道理的。你现在拥有它的方式，很明显为什么它不断递归，你永远不会告诉它不要。

我正在尝试在已定义的同一函数内调用一个函数

I am trying to call a function inside the same function that has been defined

python

python-3.5