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24 lines
567 B
Idris
24 lines
567 B
Idris
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interface Pretty a where
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pretty : a -> String
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data Bar : Type -> Type
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data Foo a = FNil | FCons a (Bar a)
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data Bar a = BNil | BCons a (Foo a)
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Pretty a => Pretty (Foo a)
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implementation Pretty a => Pretty (Bar a) where
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pretty (BNil) = "Nil"
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pretty (BCons a f) = "\{pretty a} :: \{pretty f}"
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implementation Pretty a => Pretty (Foo a) where
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pretty (FNil) = "Nil"
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pretty (FCons a f) = "\{pretty a} :: \{pretty f}"
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implementation Pretty String where
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pretty a = a
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main : IO ()
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main = putStrLn $ pretty (BCons "1" (FCons "2" (BCons "3" FNil)))
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