Data.Map, Data.IntMap documentation
Twan van Laarhoven
twanvl at gmail.com
Fri Aug 17 23:04:20 EDT 2007
Stefan O'Rear wrote:
>>>Interesting problem, but I don't see any reason why this could not
>>>be an instance of Ord.
> There's nothing stoping you from writing
> instance Ord TypeRep where compare = comparing show
> STRef could also be cheaply made Ord, ...
What we really need for this is a 'unsafe' PrimOrd class, sugesting that
the comparison is not intended for human consumption.
> class Eq a => PrimOrd a where
> primcompare :: a -> a -> Ordering
> class PrimOrd a => Ord a where
> -- needs something like class aliasses to be useble
Now the Data.Map functions can be based on PrimOrd, because we don't
actually care about the ordering. Except for to/fromAscList, which
should check the ordering is actually an Ord.
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