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@github-actions github-actions released this 30 Jun 00:14
· 653 commits to master since this release
fix: remove global `NatCast (Fin n)` instance (#8620)

This PR removes the `NatCast (Fin n)` global instance (both the direct
instance, and the indirect one via `Lean.Grind.Semiring`), as that
instance causes causes `x < n` (for `x : Fin k`, `n : Nat`) to be
elaborated as `x < ↑n` rather than `↑x < n`, which is undesirable. Note
however that in Mathlib this happens anyway!