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{-# LANGUAGE RankNTypes, QuantifiedConstraints, ConstraintKinds #-}
-- NB: disabling these if enabled:
{-# LANGUAGE NoUndecidableInstances, NoUndecidableSuperClasses #-}
module T15316 where
import Data.Proxy
{-
class Class a where
method :: a
subsume :: (Class a => Class b) => Proxy a -> Proxy b -> ((Class a => Class b) => r) -> r
subsume _ _ x = x
value :: Proxy a -> a
value p = subsume p p method
-}
subsume' :: Proxy c -> ((c => c) => r) -> r
subsume' _ x = x
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