Lean 4 fork for HoTT-compatible kernel extensions (Path types, transport, HITs). Maintained against upstream leanprover/lean4.
This PR modifies `Option.instDecidableEq` and `Option.decidableEqNone` so that the latter can be made into a global instance without causing diamonds. It also adds `Option.decidabeNoneEq`. See [Zulip](https://leanprover.zulipchat.com/#narrow/channel/270676-lean4/topic/Option.2EdecidableEqNone/near/527226250). --------- Co-authored-by: Eric Wieser <wieser.eric@gmail.com> Co-authored-by: Rob Simmons <rob@lean-fro.org> |
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