25 lines
481 B
Haskell
25 lines
481 B
Haskell
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{-# OPTIONS -cpp #-}
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module API where
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import AltData
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data Interface = Interface {
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equals :: forall t. Eq t => t -> t -> Bool
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}
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--
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-- see how it hides the internal type.. but to compile GHC still checks
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-- the type.
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--
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instance Typeable Interface where
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#if __GLASGOW_HASKELL__ >= 603
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typeOf i = mkTyConApp (mkTyCon "API.Interface") []
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#else
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typeOf i = mkAppTy (mkTyCon "API.Interface") []
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#endif
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plugin :: Interface
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plugin = Interface { equals = (==) }
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