The fundamental data type is the bitmap. Bitmaps are used to efficiently record and test sets of privileges. Bitmaps may be combined into bitmap arrays, which are contiguous groups of bitmaps indexed by integer, and bitmap hashes which are non-contiguous and may be indexed by text strings.
In addition to the bitmap-based types, there are a small number of support types that just help things along. If you think you have a case for defining a new type, please contact the author.
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