Can't call function from destructor in any class
python
Solution
The order in which objects are destroyed is undefined. This means that by the time `obj.__del__()` is called -- if it's called at all -- `test3()` may or may not have been destroyed.
There is a red box with a warning in the documentation:
Warning Due to the precarious circumstances under which `__del__()` methods are invoked, exceptions that occur during their execution are ignored, and a warning is printed to `sys.stderr` instead. Also, when `__del__()` is invoked in response to a module being deleted (e.g., when execution of the program is done), other globals referenced by the `__del__()` method may already have been deleted or in the process of being torn down (e.g. the import machinery shutting down). For this reason, `__del__()` methods should do the absolute minimum needed to maintain external invariants. Starting with version 1.5, Python guarantees that globals whose name begins with a single underscore are deleted from their module before other globals are deleted; if no other references to such globals exist, this may help in assuring that imported modules are still available at the time when the `__del__()` method is called.
In Python, one almost never overrides `__del__`. You should probably rethink your design. See How do I correctly clean up a Python object?
Problem
I want use ConfigParser in one class, it needs a call from the destructor, but then strange things happen. This is my code: ``` """ function name is test ok! test1 failed! test2 failed! test3 failed! test4 ... ok! """ def test3(): pass class Class1: def __del__(self): test3() if __name__=="__main__": obj=Class1() ``` If the function is named `test1`, `test2` or `test3`, an exception will be raised, and I can't catch it by `try except`. The traceback is: ``` E:\tc.py Exception TypeError: "'NoneType' object is not callable" in <bound method Class1.__del__ of <__main__.Class1 instance at 0x00C18F58>> ignored ``` It's so strange! Can you test it in your system? Or am I doing something wrong?