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{-# LANGUAGE MultiParamTypeClasses, FunctionalDependencies,
FlexibleInstances #-}
-- !!! Functional dependencies
-- This broke an early impl of functional dependencies
-- (complaining about ambiguity)
module ShouldCompile where
class Foo r a | r -> a where
foo :: r -> a
instance Foo [m a] (m a)
bad:: Monad m => m a
bad = foo bar
bar:: Monad m => [m a]
bar = []
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