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The main bottleneck for emit-on-change for stateless operations is really how to load the prior result. That does not necessarily have to be done. Earlier in our discussion, we have talked about using a hash code as a way of uniquely identifying the results, and then comparing those hash codes. But as noted, hash codes can vary across JVMs, and it is not a requirement that the programs on different runs return the same hash code for the exact same object. Instead, we can consider using some method distinct from Object#hashCode(). There is the possibility here that we can add a configuration for allowing emit-on-change for stateless operations. If emit-on-change is enabled, then we can use some method defined by the user i.e. generateUniqueObjectId(V result)  returning a 32-bit or 64-bit integer as an id – this method which will have stricter constraints than a normal hash code function.  This method These generated ids would be used as is the hash codes described in the Implementation section below. We store these ids instead, and compare these for equality.

This potentially can work, but the user must implement the provided method correctly. This must be stressed in further documentation. 

Implementation [DISCARDED]

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