Hi everyone, I am trying to figure out how global objects in Perspective Scope work. I have a view with a numeric entry field that will receive the input of the user. I also have a class TestGlobalScope which will take the value of the numeric entry field when its value has changed. class TestGlob…

[image] kgamble: Would checking the type like this work No idea. Test. Or better, just replace it unconditionally in the top level of the defining script. If that runs, you know it will be new code.

I did test it before I asked, was mostly asking from a memory leak standpoint. It works from a code standpoint. I am not exactly sure how Jython handles memory in this case, or if I am missing some other horrible practice here.

Replace it unconditionally in the top level of the defining script. Something like this: class myClass(): __init__(self, prior): # Copy important values from prior version, as long as they # are platform data types. Stop any threads stored in prior # and remove any of its listeners from th…

@pturmel , @Kevin.Herron , @kgamble Thank you very much for the information. However, I still don’t have the full answer to my question. Why did it work in my second scenario?

My guess is that its related to scripting restarts during a save/preview update and something to do with local variables in the runScript functions, vs using the actual global library to set the variable inside the runScript function vs not. However I am not really positive, that’s just a guess inc…

Where should the singleton lock code execute? Inside the actual init method of the class? I see that you didnt put it in there in this example.

Use it everywhere you work with the singleton class. That prevents replacement of the instance you are working with until you release the lock. As long as every locked section leaves the singleton in a consistent state, you can’t break it. The lock is not needed in the init method of the class be…

Okay, so say I want to use it in a function, is below a close representation of how I would get the instance and verify it isn’t locked? Then I presume if it is I would need to try again in X seconds, or raise an exception, or something. def myFunction(): _g = system.util.getGlobals() singletonLo…

You’re making it too hard. Just this, when the function is in the same project script: def myFunction(): with singletonLock: myInstance = _g['singletonKey'] myInstance.performSomeAction() Anywhere else, do this: with path.to.script.singletonLock: myInstance = path.to.script._g['singletonKe…

Oh okay, I didnt realize that the section that creates the singleton lock just executes when the project script is referenced, so it would ensure that it exists and I could access it that way. Would there be any benefit to adding that content into the __enter__ and __exit__ methods on the singleto…

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Global objects in Perspective Scope

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