Re: [Jython-dev] Python object not gc()'d, 21b1

[<bc...@wo...>]

[Ype Kingma]

>Dear jythoneers,
>
>This is a rather involved bug, so I hope it is JVM dependent.
>It shows up in rather unusual circumstances.

[example running __del__() method in clear globals snipped]

It isn't really a mystery and exactly the same thing happens in CPython.
When the __del__() is executed, the globals no longer have a reference
to the module level println function. The result is a common NameError
exception.

Unfortunately Jython 2.1b1 doesn't inform you of the exception in the
way it should. When I fix that bug, your program will the same way, but
it will write:

__main__.executor
Hello   <<unknown>.deltest1 instance at 6467398>
Hello2   <<unknown>.deltest2 instance at 5935979>
after del __main__.executor
Goodbye <<unknown>.deltest1 instance at 6467398>
Goodbye2 <<unknown>.deltest2 instance at 5935979>

__main__.clearingExecutor
Hello   <<unknown>.deltest1 instance at 13226366>
Goodbye <<unknown>.deltest1 instance at 13226366>
Hello2   <<unknown>.deltest2 instance at 14919969>
Exception NameError: println in <unbound method deltest2.__del__>
ignored
after del __main__.clearingExecutor


which at least contain a usefull hint about the real problem.

Thanks for making the example available. Without it, the bug would never
have been uncovered this easily.

regards,
finn