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Reference counting mystery
#1
Consider this code:

import gc

for i in range(10):
    gc.collect()
    if True:
        all_objects = gc.get_objects()
        print "Number of objects =", len(all_objects)
    else:
        print "Number of objects =", len(gc.get_objects())
With the True block, the number of objects increments by 1 on every iteration (except the first). With the False block, it does not. The result of the get_objects function call has one reference (by all_objects), but on the next iteration all_objects gets bound to a new result. At that point, I don't see who is still holding a reference to the first result, so it isn't clear to me why the number of objects keeps climbing. If it is gc itself that is holding a reference, then I don't see what good gc is for debugging a memory leak if it is causing a memory leak itself.

I am running Python 2.7, although I see the same behavior with Python 3.
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#2
with if True this part will always be executed or in other words else part is NEVER executed
If you can't explain it to a six year old, you don't understand it yourself, Albert Einstein
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#3
Change the if True to if False to execute the other case.
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#4
(Jul-23-2018, 10:57 PM)beezergeezer Wrote: Change the if True to if False to execute the other case.
:-) if you change it to False then this part will never be executed. The point is I don't see the reason for using this if-else block if the conditions are fixed True and False
If you can't explain it to a six year old, you don't understand it yourself, Albert Einstein
How to Ask Questions The Smart Way: link and another link
Create MCV example
Debug small programs

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#5
The reason for the if-else block is to make it easy to run the program once to observe the behavior in one case and then again, after changing the if line, to observe the behavior in the other case.
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