Ashley Yakeley ashley at
Thu Sep 18 17:01:08 EDT 2003

In article <20030918091948.GA29877 at>,
 Ross Paterson <ross at> wrote:

> NHC doesn't have ST (rank-2 types).  In Hugs, they are now
> 	newtype IO a = IO ((a -> IOResult) -> IOResult)
> 	newtype ST s a = ST (forall r. (a -> r) -> r)

Oh now that's interesting. Presumably in Hugs IO and ST s could be made 
instances of MonadCont very easily? How does Hugs do fixIO?

Ashley Yakeley, Seattle WA

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