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You need to understand a bit tables and methods, basically OOP programming. GetPropertyChangedSignal is a method that is usable by some instances in the game. That means you cannot use it on data type. Thats like if you wanted to use :GetChildren() on a table. Simplified, you cannot use most of in-build functions on data types, only instances that are in game. Boolean value is an instance, but bool data type you used is just data type, just variable of certain type! Maybe learn lua itself first, more about how it works, and after move to roblox coding :D. I hope this helped you, have a nice day.
3 comments
Do not code aimlessly. It appears you have no knowledge on how Instance:GetPropertyChangedSignal is meant to be used; pay a visit to the API reference.
As for detecting when a variable changes, that's not possible. If you need something done, you know exactly where the mutation occurs.
poor ziffixture