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{-# LANGUAGE ViewPatterns, GADTs #-}
module T30243( getUL ) where
import Data.Kind
import Unsafe.Coerce
newtype AsUnitLoop a (b :: Type) (c :: Type) = UnsafeUL a
data SafeUnitLoop a b c where
SafeUnitLoop :: !a -> SafeUnitLoop a () ()
mkSafeUnitLoop :: AsUnitLoop a b c -> SafeUnitLoop a b c
mkSafeUnitLoop (UnsafeUL a) = unsafeCoerce (SafeUnitLoop a)
getUL :: AsUnitLoop a b c -> a
getUL (mkSafeUnitLoop -> SafeUnitLoop a) = a
-- There should be no unsafeEqualityProof in the output
-- when compiled with -O
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