As for what it does, it allows you to store an interval in Lucene, so you could store 1792 - 1796 or you could store 140000 - 125235466734. It uses a similar a

As for what it does, it allows you to store an interval in Lucene, so you could store 1792 - 1796 or you could store 140000 - 125235466734. It uses a similar algorithm as the one used to store numbers so that it doesn't have to store millions of terms in the second example. (we're pretty surprised by the response too!)