Re: How to clean a module?

ai a écrit :
It assumes that there is a module A which have two global variables X
and Y. If I run "import A" in the IDLE shell, then I can use A.X and
A.Y correctly. But if I want to change the module A and then delete
the variable Y, I find I can use A.Y just the same as before!

It's unlikely to be true, see below.

In fact, I have tried all the following methods but can't remove the
A.Y:
execute "import A" again
"reload(A)"
"del A; import A"
Yes, if you use "del A.Y", it works. But it is stupid since there are
probably many names. In my thought, if no one references objects in A,
"del A" will release all memory about A. But it seems that the fact is
not. So I can not refresh the namespace to follow changes of a module
easily and I will worry about the memory if I del a module.
I want to know if there is a way to clear a module entirely.


Actually I do not see your problem and your exact need, when I type the following in python prompt I just see expected behavior, what is a problem to you ? Maybe you could post a code explaining it.


In [64]: import a



In [65]: a.X

Out[65]: 0



In [66]: a.X = 2



In [67]: del a



In [68]: import a as b



In [69]: b.X

Out[69]: 2



In [71]: for name in [ n for n in b.__dict__ if not n.startswith('__') ] :
....: b.__dict__.__delitem__(name)

....:

....:



In [72]: b.X

---------------------------------------------------------------------------

<type 'exceptions.AttributeError'> Traceback (most recent call last)


C:\Documents and Settings\maric\Bureau\<ipython console> in <module>()



<type 'exceptions.AttributeError'>: 'module' object has no attribute 'X'



In [73]: reload(b)

Out[73]: <module 'a' from 'a.pyc'>



In [74]: b.X

Out[74]: 0


In [75]: del b.X



In [76]: del b



In [77]: import a



In [78]: a.b

---------------------------------------------------------------------------

<type 'exceptions.AttributeError'> Traceback (most recent call last)


C:\Documents and Settings\maric\Bureau\<ipython console> in <module>()



<type 'exceptions.AttributeError'>: 'module' object has no attribute 'b'



.

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