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{-# LANGUAGE TypeFamilies, DataKinds, KindSignatures, TypeOperators #-}
module T10776 where
import GHC.TypeLits (Nat, Natural, Symbol, KnownNat)
import Data.Type.Equality ((:~:)(..))
import Data.Proxy
nat_is_natural :: Nat :~: Natural
nat_is_natural = Refl
data NatPair = TN Natural Natural
type X = TN 1 101
type family SecondNat (a :: NatPair) :: Nat where
SecondNat ('TN _ a) = a
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