code: public static <K, V> MergeResult<K, V> mergeRightIntoLeft(LinkedOptionalMap<K, V> left, LinkedOptionalMap<K, V> right) {
  		LinkedOptionalMap<K, V> merged = new LinkedOptionalMap<>(left);
  		merged.putAll(right);
  
  		return new MergeResult<>(merged, isLeftPrefixOfRight(left, right));
  	}
docs: Tries to merges the keys and the values of @right into @left.