Post #4169135

My current concept for the #Kittyscript compiler involves compile-time side effects. But because a later expression can change a previous expression and potentially remove it, it needs to have a way to roll back side effects too, at least the effects on the compilation output object. For example an expression defining a function must be able to delete the function if the expression gets removed. This could probably be handled with an optional cleanup callback, kinda like React's useEffect.