17 lines
391 B
Plaintext
17 lines
391 B
Plaintext
module Exists where
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import Prelude
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import Data.Exists (Exists, mkExists)
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-- type Exists f = forall result. (forall a. f a (a -> result)) -> result
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type Forall :: forall k. (k -> Type) -> Type -> Type
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type Forall f r = forall a. f a -> r
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{- type Showable a f = Show a => f
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type EConstructor f = forall a. f a (a -> Exists f)
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mkShowable :: EConstructor Showable
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mkShowable a f = f a -} |