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27 lines
539 B
Idris
27 lines
539 B
Idris
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%default partial
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foo : Maybe a -> a
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foo (Just x) = x
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data Vect : ? -> Type -> Type where
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Nil : Vect Z a
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(::) : a -> Vect k a -> Vect (S k) a
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data Fin : Nat -> Type where
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FZ : Fin (S k)
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FS : Fin k -> Fin (S k)
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lookup : Fin n -> Vect n a -> a
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lookup FZ (x :: xs) = x
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lookup (FS k) (x :: xs) = lookup k xs
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lookup' : Fin n -> Vect n a -> a
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lookup' (FS k) (x :: xs) = lookup' k xs
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lookup'' : Fin n -> Vect n a -> a
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lookup'' n xs = lookup' n xs
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main : IO ()
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main = do let x = foo Nothing
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printLn (the Int x)
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