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{-# LANGUAGE GADTs, DataKinds, LinearTypes, KindSignatures, ExplicitForAll, TypeApplications #-}
module MultConstructor where
import GHC.Types
data T p a where
MkT :: a %p -> T p a
data Existential a where -- #18790
MkE :: a %p -> Existential a
f1 :: forall (a :: Type). T 'Many a %1 -> (a,a)
f1 (MkT x) = (x,x)
f2 :: forall (a :: Type) m. T 'Many a %1 -> T m a
f2 (MkT x) = MkT x
f3 :: forall (a :: Type). a %1 -> T 'One a
f3 = MkT
g1 :: forall (a :: Type). a %1 -> Existential a
g1 x = MkE x
g2 :: forall (a :: Type). Existential a -> a
g2 (MkE x) = x
vta :: Int %1 -> Existential Int
vta x = MkE @Int @'One x
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