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21 lines
538 B
Idris
21 lines
538 B
Idris
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parameters (eq : a -> a -> Bool)
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lookup : a -> List (a, b) -> Maybe b
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lookup x [] = Nothing
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lookup x ((k, v) :: ys)
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= if eq x k
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then Just v
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else lookup x ys
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data Dict : Type -> Type where
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MkDict : List (a, b) -> Dict b
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lookupK : a -> Dict b -> Maybe b
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lookupK k (MkDict xs) = lookup k xs
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testDict : Dict {a=Int} (==) String
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testDict = MkDict _ [(0, "foo"), (1, "bar")]
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parameters (y : ?) -- test that the type of 'y' can be inferred
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foo : (x : Int) -> x = y -> Int
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foo x@_ Refl = 42
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