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>
9 lines
184 B
Text
9 lines
184 B
Text
def sum (as : Array Nat) : Nat :=
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go 0 0
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where
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go (i : Nat) (s : Nat) : Nat :=
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if h : i < as.size then
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go (i+1) (s + as[i])
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else
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s
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termination_by as.size - i
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