3a408e0e54
This PR changes the signature of `Array.get` to take a Nat and a proof, rather than a `Fin`, for consistency with the rest of the (planned) Array API. Note that because of bootstrapping issues we can't provide `get_elem_tactic` as an autoparameter for the proof. As users will mostly use the `xs[i]` notation provided by `GetElem`, this hopefully isn't a problem. We may restore `Fin` based versions, either here or downstream, as needed, but they won't be the "main" functions. --------- Co-authored-by: David Thrane Christiansen <david@davidchristiansen.dk>
22 lines
505 B
Text
22 lines
505 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 → Id Unit
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def bad2 (bs : Array Bool) (n : Nat) : Id Unit := do
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for idx in [:n] do
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let b := getElem bs idx
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f b
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def bad3 (bs : Array Bool) (n : Nat) : Id Unit := do
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for h : idx in [:n] do
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let b := getElem bs idx
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f b
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end Ex
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