Module columnar::sums::rank_select

Stores for maintaining discriminants, and associated sequential indexes.

The sequential indexes are not explicitly maintained, but are supported by a rank(index) function that indicates how many of a certain variant precede the given index. While this could potentially be done with a scan of all preceding discriminants, the stores maintain running accumulations that make the operation constant time (using additional amortized memory).

Structs

• RankSelect
  A store for maintaining Vec<bool> with fast rank and select access.