: The next step would be to actually use it... replacing BitSet with : OpenBitSet in BitDocSet (an alternative would be to create another : DocSet type, but that gets more complicated).
The one reason i can think of why having both types of DocSet could be advantagous, is if the memory footprint of an OpenBitSet is significantly larger then a regular BitSet -- if so, it would be nice to have a configuration option so that people who expect to use lots of very large (dense) DocSets, but aren't super concerned about speed can choose the to use BitSet based docsets instead of OpenBitSet based. (similar to the current option for HashDocSet) -Hoss
