[Tutor] Clueless

[Marilyn Davis]

On Sat, 13 Mar 2004, Rich Krauter wrote:

> On Sat, 2004-03-13 at 20:44, Marilyn Davis wrote:
> > I can't even give this one a good subject line, I'm so clueless.
> > 
> > I'm trying to make something meaningful using __getattribute__.
> > What a bear to stop all the infinite loops!
> > 
> > But, finally, I have all that under control. 
> > 
> > So, my classes are:
> > 
> >   Logger                       object
> >    /|\                        /|\  /|\
> >     |                          |    |
> >   Watched  --------------------     |
> >    /|\                            list
> >     |                              /|\
> >     |                               |
> >   WatchedList  ---------------------
> > 
> > All is cool as long as I don't implement Logger.__del__
> > 
> > But if I do, crash-city when an object goes away:
> > 
> > Exception exceptions.AttributeError: "'NoneType' object has no
> > attribute 'close'" in <bound method WatchedList.__del__ of []> ignored
> > 
> > If anyone has time and inclination, could you help?
> > 
> > Thank you so much.
> > 
> > Marilyn Davis
> > 
> > #!/usr/bin/env python2.2
> > '''New style classes have __getattribute__ which intercept
> > all references to attributes, ones that exist and don't
> > exist.  We'll make a Watched class that logs all accesses and
> > assignments.'''
> > 
> > import time
> > 
> > class Logger:
> >     def __init__(self, name):
> >         self.file = open(name, 'w')
> >     def logit(self, entry):
> >         self.file.write(time.ctime(time.time()))
> >         self.file.write('\n' + entry + '\n')
> >         self.file.flush()
> > #    def __del__(self):
> > #        self.file.close()
> > 
> 
> Hi Marilyn,
> 
> I added this to the Watched class, and it seemed to help:
> 
> def __del__(self):
>         Logger.__del__(self.log)

Did you do anything else?  I still get the same crash.  You don't?
What version of python?

> 
> Also, I wouldn't use 'file' as an attribute name. It's in synonym for
> 'open'.

I didn't know that.

Thank you. I changed that too.

But I'm still stumped.

Thank you for beating your head against this too.

Marilyn

> 
> Hope that helps.
> 
> Rich
> 
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