Alternatives (2/2)
Set::Bag - implements multisets
Set::IntSpan - optimized for .newsrc file type sets (also supported
by Bit::Vector, but need more memory)
Set::Object - implements sets of arbitrary objects (can be simulated
with Bit::Vector using lookup table, set operations will then be faster)
Set::Scalar - similar to Set::Object (?), but also allows recursion
(set of sets)
Set::Window - optimized for intervals of integers (needs much less
memory than Bit::Vector, but only of limited use since the whole
interval is either in or out)