Fix incorrect kani::index example in loop-contracts documentation#4539
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tautschnig wants to merge 1 commit intomodel-checking:mainfrom
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Fix incorrect kani::index example in loop-contracts documentation#4539tautschnig wants to merge 1 commit intomodel-checking:mainfrom
tautschnig wants to merge 1 commit intomodel-checking:mainfrom
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The existing example intended to demonstrate how `kani::index` works with loop invariants, but had a mismatch between the invariant and the loop body: - The loop invariant used `sum <= (kani::index as u32 * 20)` suggesting that array element values (each ≤ 20) were being summed - However, the loop body was adding `i` (the index) instead of `*j` (the array element value) - The use of `enumerate()` was also unnecessary for the example's purpose Co-authored-by: Alex Bagnall Resolves: model-checking#4534
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Pull request overview
Updates the Kani book’s loop-contracts documentation to fix the kani::index example so the loop body matches the stated invariant (summing array elements bounded by 20).
Changes:
- Replace the
enumerate()loop that incorrectly summed indices with a simpler loop that sums array values. - Remove unnecessary iterator plumbing to better focus the example on
kani::indexand the invariant.
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The existing example intended to demonstrate how
kani::indexworks with loop invariants, but had a mismatch between the invariant and the loop body:sum <= (kani::index as u32 * 20)suggesting that array element values (each ≤ 20) were being summedi(the index) instead of*j(the array element value)enumerate()was also unnecessary for the example's purposeCo-authored-by: Alex Bagnall
Resolves #4534
By submitting this pull request, I confirm that my contribution is made under the terms of the Apache 2.0 and MIT licenses.