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27 lines
632 B
Plaintext
27 lines
632 B
Plaintext
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data Nat : Type where
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Z : Nat
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S : Nat -> Nat
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namespace Stream
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public export
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data Stream : Type -> Type where
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Cons : $a -> Inf (Stream $a) -> Stream $a
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ones : Stream Integer
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ones = Cons 1 ones
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countFrom : Integer -> Stream Integer
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countFrom $x = Cons x (countFrom (prim__add_Integer 1 x))
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data List : Type -> Type where
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Nil : List $a
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Cons : $a -> List $a -> List $ a
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take : Nat -> Stream $a -> List $a
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take Z $xs = Nil
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take (S $k) (Cons $x $xs) = Cons x (take k xs)
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every2nd : Nat -> Stream $a -> List $a
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every2nd Z $xs = Nil
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every2nd (S $k) (Cons _ (Cons $x $xs)) = Cons x (every2nd k xs)
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