[Haskell-cafe] Confused about type seen in the wild
alex.solla at gmail.com
Thu Apr 10 18:44:25 UTC 2014
On Thu, Apr 10, 2014 at 11:40 AM, Andres Löh <andres at well-typed.com> wrote:
> Sorry for continuing to reply to myself. But all this seems fixed in 7.8.1:
> Prelude> let whee :: (Show a, Eq a, a) => Bool; whee x = x == x && null
> (show x)
> Expected a constraint, but 'a' has kind '*'
> In the type signature for 'whee': whee :: (Show a, Eq a, a) => Bool
> Prelude> let whee :: (Show a, Eq a) => a => Bool; whee x = x == x &&
> null (show x)
I don't have a GHC 7.8 handy. Can you check to see if:
whee :: Show a => Eq a => (a -> Bool)
works over there?
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