Copyright © 2002-2016 Akinori MUSHA <knu@iDaemons.org>
Documentation by Akinori MUSHA and Gavin Sinclair.
All rights reserved. You can redistribute and/or modify it under the same terms as Ruby.
This library provides the Set class, which deals with a collection of unordered values with no duplicates. It is a hybrid of Array’s intuitive inter-operation facilities and Hash’s fast lookup. If you need to keep values sorted in some order, use the SortedSet class.
to_set is added to Enumerable for convenience.