muhuk asks don't you (KDE users) feel all vulnerable and exposed without a good trash management system?

26 responses to this plurk.

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  December 16, 2008 at 18:01 shaf nice to see ppl giving back to the community.. ps __trash_singleton ?? (!!)
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  December 16, 2008 at 18:01 shaf Have you worked than one out yet ?
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  December 16, 2008 at 18:18 muhuk says shaf: that's very very old code. It was one of my first projects for learning python.
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  December 16, 2008 at 18:18 muhuk says But it still works on my box New version is cooking, soon to be committed.
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  December 16, 2008 at 18:31 shaf asks if it's that simple to implement the singleton pattern in python
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  December 16, 2008 at 19:38 muhuk says shaf: stackoverflow.com/questions/31875/is-there-a-simple-elegant-way-to-define-singletons-in-python
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  December 16, 2008 at 21:54 timka.org says shaf: I use __new__ which always returns the single instance stored in a class attribute
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  December 16, 2008 at 21:58 shaf yeah but what's to stop you from executing the script using another python intepreter ? Singleton breaks.
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  December 16, 2008 at 21:59 shaf It's just that singleton is the simplest pattern to understand but can be tricky to implement if you don't understand your compiler/interptr
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  December 16, 2008 at 22:12 timka.org says shaf: Another interpreter runs another instance of your program which has its own singleton instance.
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  December 16, 2008 at 22:45 shaf exactly
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  December 16, 2008 at 22:55 timka.org says shaf: I mean Singleton is usually limited to one process no matter what language you use, so multiple *program* instances is out of scope.
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  December 16, 2008 at 22:58 shaf timka_org yep. I know all this already. But as any good programmer would know, singleton in practice is not guarenteed
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  December 16, 2008 at 22:58 shaf this is why in any good production environment. Singleton is frowned upon
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  December 16, 2008 at 23:01 shaf especially read the last few paragraphs of this ... en.wikipedia.org/wiki/Singleton_pattern#Implementation
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  December 16, 2008 at 23:07 timka.org says Yeah, in our production environment at work two instances of our app can fuck up the DB just because nobody cared about proper locking
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  December 16, 2008 at 23:10 timka.org says It's about thread-safety inside single process, but you were talking about multiple processes
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  December 16, 2008 at 23:11 shaf hence the reason for me to have mixed feelings about it. If used - use it carefully
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  December 16, 2008 at 23:12 shaf well some idiot programmers assume singletons to work across processes too
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  December 16, 2008 at 23:14 timka.org says Agree. And punish those who break the conventions!
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  December 16, 2008 at 23:18 timka.org says I think you can only fire or train them. Hard choice...
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  December 17, 2008 at 07:22 muhuk says on the other hand, most of the time singleton is not really needed in practice. Surely there is one trash (per user) but I have come to...
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  December 17, 2008 at 07:23 muhuk says ...realize I don't need a singleton trash wrapper class at all. It is even making things harder to unittest.
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  December 17, 2008 at 07:24 muhuk says Btw, a singleton shouldn't be confused as a concurrency mechanism (especially in multi-process systems).
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  December 17, 2008 at 07:34 timka.org says Anyway, Singleton is just an object creation pattern, conceptually it has nothing to do with concurrency.
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  December 17, 2008 at 07:37 timka.org says However, correct implementations must be aware of the used concurrency model