[feature request] Special method to be called on class instance to ask (and wark object) before garbage collection

[AnimusPEXUS]

On Monday, 1 August 2022 at 11:21:43 UTC, vit wrote:
> GC.addRoot: GC.removeRoot:

thanks, I know about those.
But my point is not just to preserve objects from being GCed, but 
object's to be notified before GC, so objects could do some 
additional cleanups.