// RIANs generate new fact handles on-demand to wrap tuples and need special procedures when serializing to persistent storage
ObjectHashMap memory = (ObjectHashMap) context.wm.getNodeMemory( (NodeMemory) sink );
InternalFactHandle ifh = (InternalFactHandle) memory.get( leftTuple );
// first we serialize the generated fact handle ID
// context.out.println( "FactHandle id:"+ifh.getId() );
stream.writeInt( ifh.getId() );
stream.writeLong( ifh.getRecency() );
writeRightTuples( ifh, context );
stream.writeShort( PersisterEnums.END );