Just out of curiosity, why do you care so much about the lifecycle of an object. I can see why you might want to know in the case where you're representing an

Just out of curiosity, why do you care so much about the lifecycle of an object. I can see why you might want to know in the case where you're representing an external resource, e.g. an open file, but otherwise, I don't see any reason to care about it. In face, with persistent data structures, you can't know. The same is true of share (immutable) data with multiple threads. You can't know the lifetime.