ref: 3c4c38a565695f5d0ae07b45eff1e1cf9fe4c324 dir: /tests/Eq1.hs/
module Eq1 where class Eq1 f where eq1 :: (Eq a) => f a -> f a -> Bool instance Eq1 Maybe where eq1 = (==) main :: IO () main = do let x = Just (1::Int) print $ eq1 x x