how can i fix this?
Mmmh I really need some haskell type class traingings ;)
============= test file ==============================================
module Main where
import HList
import HOccurs
import Control.Monad.Reader
class Get a b where
get :: a -> b
data D1 = D1 Int -- dummy type
type ActionMonad a l = forall l. (HOccurs D1 l)
=> ( ReaderT l IO a )
data CR = CR (ActionMonad Bool ())
instance Get CR (ActionMonad Bool ()) where
get (CR a) = a
main = do
print "test"
============= error ==================================================
|| [1 of 1] Compiling Main ( uqt.hs, uqt.o )
||
uqt.hs|16| 0:
|| Illegal polymorphic or qualified type: forall l.
|| (HOccurs D1 l) =>
|| ReaderT l IO Bool
|| In the instance declaration for `Get CR (ActionMonad Bool ())'
======================================================================
Marc
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