marking variable as constant

so just to give a little more context. I have tons of clickable buttons, instead of creating each button as a separate object, i only have 1 object with an instance variable that holds the name of a callback function.

now getting the button that is clicked i have been using the UID, but having all those magic numbers get a bit cumbersome sometimes, so now i am think of just adding a bunch of variables (constants) so i can give the magic number more context.

Why is using uid bad? Once your object is created that I'd won't change for that object type?

You might want to check out Ash's post about optimising events with function binding, he talks about a strategy used in the expression compiler for constants.

https://www.construct.net/en/blogs/ashleys-blog-2/optimising-events-with-function-binding-964

when setting a variable as a constant, does that get pre processed so all the usages get replaced with its literal value? or is it just like a variable that does not have setter?

IIRC, the C3 runtime expression compiler does replace it with its actual literal.