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{-# OPTIONS_GHC -fno-warn-redundant-constraints #-}
module ShouldSucceed where
class C a where
op1 :: a -> a
class (C a) => B a where
op2 :: a -> a -> a
instance (B a) => B [a] where
op2 xs ys = xs
instance C [a] where
op1 xs = xs
{- This was passed by the prototype, but failed hard in the new
typechecker with the message
Fail:No match in theta_class
-}
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