16 lines
379 B
Text
16 lines
379 B
Text
namespace Ex
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class GetElem (Cont : Type u) (Idx : Type v) (Elem : outParam (Type w)) where
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getElem (xs : Cont) (i : Idx) : Elem
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export GetElem (getElem)
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instance : GetElem (Array α) Nat α where
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getElem xs i := xs.get ⟨i, sorry⟩
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opaque f : Option Bool → Bool
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opaque g : Bool → Bool
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def bad (xs : Array Bool) : Bool :=
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let x := getElem xs 0
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f x && g x
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end Ex
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