Exploration: Holding Operators

Sometimes stuff needs to be re-calculated based on something every frame. These operators help "holding" a cached value for an amount of time, and re-emitting them at every tick.

- Held items should not be cloned, but replayed behind a read only pointer.
- Or if it's writable, maybe taking it would stop the hold prematurely

Note: This may be unneeded or even counter-productive, as there are other solution to keep referring to an unchanged value while reacting to something faster.