On 18/07/13 17:58, Patrick R. Michaud wrote:
[...] Sets do not implement well on a computer.
Let me strongly disagree with this statement. Sets implement *very well* on computer, it just suffices to know how to do it.
You want a constructive proof? Check the CDuce language (http://www.cduce.org) where types are sets of values, you have all the set-theoretic operations listed in a previous mail, pattern matching is based on type-case (that is dynamic testing the type of the matched value), you have dynamic overloading as you do in Perl6. As added bonus, the language is statically type-safe and you can also have polymorphic functions (not implemented yet, but should be available in an year or so). ... and efficiency is not an issue.
My two cents' worth Beppe
