Lean 4 fork for HoTT-compatible kernel extensions (Path types, transport, HITs). Maintained against upstream leanprover/lean4.
47228b94fd
This PR implements support for arbitrary `grind` parameters. The feature is similar to the one available in `simp`, where a proof term is treated as a local universe-polymorphic lemma. This feature relies on `grind -revert` (see #11248). For example, users can now write: ```lean def snd (p : α × β) : β := p.2 theorem snd_eq (a : α) (b : β) : snd (a, b) = b := rfl /-- trace: [grind.ematch.instance] snd_eq (a + 1): snd (a + 1, Type) = Type [grind.ematch.instance] snd_eq (a + 1): snd (a + 1, true) = true -/ #guard_msgs (trace) in set_option trace.grind.ematch.instance true in example (a : Nat) : (snd (a + 1, true), snd (a + 1, Type), snd (2, 2)) = (true, Type, snd (2, 2)) := by grind [snd_eq (a + 1)] ``` Note that in the example above, `snd_eq` is instantiated only twice, but with different universe parameters. As described in #11248, the new feature cannot be used with `grind +revert`. |
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