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Re: LAST^2 CALL for SRFI 113, Sets and Bags

This page is part of the web mail archives of SRFI 113 from before July 7th, 2015. The new archives for SRFI 113 contain all messages, not just those from before July 7th, 2015.



Kevin Wortman scripsit:

> That is what I'd expect, but a reader might be forgiven for thinking that a
> power bag is the same as the power set of the unique elements of the bag.
> In other words, it might help to clarify that the power bag is a set of
> bags, not a set of sets.

It's actually a bag of bags: consequently, it has 2^n elements whether
they are the same or not.  The power bag of {1, 1} is {{}, {1}, {1},
{1, 1}}.

Unfortunately, I failed to commit my code and it got wiped, so I have to
reimplement these two procedures.

--
John Cowan          http://www.ccil.org/~cowan        cowan@xxxxxxxx
"The exception proves the rule."  Dimbulbs think: "Your counterexample proves
my theory."  Latin students think "'Probat' means 'tests': the exception puts
the rule to the proof."  But legal historians know it means "Evidence for an
exception is evidence of the existence of a rule in cases not excepted from."