Proposal: Bounded instance for IntSet (ticket #1953)

Ross Paterson ross at soi.city.ac.uk
Sun Dec 2 18:53:36 EST 2007


On Sun, Dec 02, 2007 at 03:45:40PM -0800, David Benbennick wrote:
> I propose to add a Bounded instance to IntSet.hs.
> 
> IntSet is in Ord, and there are only finitely many instances of
> IntSet. Therefore there is a min IntSet and a max IntSet. It turns out
> these bounds are very simple:
> 
> instance Bounded IntSet where
>     minBound = empty
>     maxBound = singleton maxBound

These are the minimum and maximum under the Ord instance (also for Set),
but what is the intuition behind that ordering?


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