[Tutor] How do I destroy class instances ?

[dave selby]

On 24/02/2008, Dave Kuhlman <dkuhlman at rexx.com> wrote:
> On Sun, Feb 24, 2008 at 04:14:02PM +0000, dave selby wrote:
>  > I have created a list of class instances, works a treat. I need to be
>  > able to re __init__ the instances on a SIGHUP so I guess the best way
>  > is to destroy them & re make them.
>  >
>  > err ... how do I destroy an instance ?
>
>
> It is not likely that you need to.
>
>  When your instances are no longer referenced (nothing points to
>  them, so to speak), they will be garbage collected.  Here is an
>  illustraction -- This code collects three instances of class
>  MyClass in a list, then later "forgets" them:
>
>     myinstances = []
>     myinstances.append(MyClass())
>     myinstances.append(MyClass())
>     myinstances.append(MyClass())
>         o
>         o
>         o
>     myinstances = []
>
>  Or, if there are resources that are held onto by each instance and
>  need to be cleaned up, for example an open file.  Then do something
>  like the following:
>
>     for inst in myinstances:
>         inst.cleanup()
>     myinstances = []
>
>  where "cleanup" is a method implemented in each class that needs to
>  cleanup/release resources.
>
>  But, remember that, if there are objects that are referred to by
>  your instances and *only* your instances, then when your instances
>  go away (are garbage collected), those other things will also
>  automatically go away, too.  No extra work is needed.
>
>  It takes a little thought before you will figure out that this is
>  something that needs (almost) no thought.

Thanks for replying, I have been away from Python for quite a while,
being dabbleing in C++ on a KDE4 app. I Forgot just how friendly
Python is :)

Cheers

Dave



>
>  Hope this helps.
>
>  - Dave
>
>
>  --
>  Dave Kuhlman
>  http://www.rexx.com/~dkuhlman
>
> _______________________________________________
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>


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