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{-# OPTIONS_GHC -w #-}
{-# LANGUAGE FlexibleInstances, UndecidableInstances #-}
module ShouldCompile where
import Control.Monad.Reader
instance Eq (a -> b) where
_ == _ = error "whoops"
instance Show (a -> b) where
show = const "<fun>"
-- This is the example from Trac #179
foo x = show (\_ -> True)
-- This is the example from Trac #963
instance (Num a, Monad m, Eq (m a), Show (m a)) => Num (m a) where
test = 1 True
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