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POOn second initialization of an object, why is __init__ called before __del__?
 

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  1. POOn second initialization of an object, why is __init__ called before __del__?
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    <p>Consider the following example code</p> <pre><code>class A: def __init__(self, i): self.i = i print("Initializing object {}".format(self.i)) def __del__(self): print("Deleting object {}".format(self.i)) for i in [1, 2]: a = A(i) </code></pre> <p>Creating the object within the loop was intended to assure that the destructor of A would be called before the new A object would be created. But apparently the following happens:</p> <blockquote> <p>Initializing object 1</p> <p>Initializing object 2</p> <p>Deleting object 1</p> <p>Deleting object 2</p> </blockquote> <p>Why is the destructor of object 1 only called after the new object has been initialized? Is this an intended behaviour? I know that the for loop has no own scope in python. In C++, for example, the destructor of 1 would certainly be called before the constructor for object 2 (at least if the object is declared within the loop).</p> <p>In my program I want to assure that the old object is deleted before the new one is created. Is there another possibility apart from deleting <code>a</code> explicitly at the end of the for loop?</p> <p>Thanks in advance.</p>
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    1. COInteresting thing happen if you change the loop to over `[1,2,3]`.
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    2. COThis would make a nice interview question.
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    3. CORe last paragraph: You don't want to do that. Because you can't (GC is non-deterministic and refcounting is an implementation detail), and you don't need to anyway. If you have resources to dispose, use a context manager (`with` statement) or add a method like `.close()` and make sure it's called.
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