Yes, but you have to wrap it up:
{-# LANGUAGE RankNTypes #-}
-- obviously not to useful for this example :)
newtype Id = Id (forall a. a -> a)
f :: IO Id
f = return (Id id)
main = do
Id g <- f
print $ g 1
print $ g "ciao"
Can I ask what you're trying to do with this?
Patrick
On Mon, Jun 15, 2015 at 3:11 PM, Paolino
Hello list, I'm trying to accomplish something along this line
{-# LANGUAGE ScopedTypeVariables #-}
f :: IO (a -> a) f = return id
main = do (g :: a -> a) <- f print $ g 1 print $ g "ciao"
Is it possible or I have to call f more than once to get different g's
Thanks
paolino
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