Lean 4 fork for HoTT-compatible kernel extensions (Path types, transport, HITs). Maintained against upstream leanprover/lean4.
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Leonardo de Moura aaec0f584c
feat: ac normalization in grind (#10146)
This PR implements the basic infrastructure for the new procedure
handling AC operators in grind. It already supports normalizing
disequalities. Future PRs will add support for simplification using
equalities, and computing critical pairs. Examples:
```lean
example {α : Sort u} (op : α → α → α) [Std.Associative op] (a b c : α)
    : op a (op b c) = op (op a b) c := by
  grind only

example {α : Sort u} (op : α → α → α) (u : α) [Std.Associative op] [Std.LawfulIdentity op u] (a b c : α)
    : op a (op b c) = op (op a b) (op c u) := by
  grind only

example {α : Type u} (op : α → α → α) (u : α) [Std.Associative op] [Std.Commutative op] 
    [Std.IdempotentOp op] [Std.LawfulIdentity op u] (a b c : α)
    : op (op a a) (op b c) = op (op (op b a) (op (op u b) b)) c := by
  grind only

example {α} (as bs cs : List α) : as ++ (bs ++ cs) = ((as ++ []) ++ bs) ++ (cs ++ []) := by
  grind only

example (a b c : Nat) : max a (max b c) = max (max b 0) (max a c) ∧ min a b = min b a := by
  grind only [cases Or]
```
2025-08-27 03:28:30 +00:00
.github chore: CI: cache again on failure (#10137) 2025-08-26 14:47:05 +00:00
doc chore: fix spelling errors (#10042) 2025-08-22 07:23:12 +00:00
images
releases_drafts chore: updates to release_checklist.md (#7817) 2025-04-04 03:45:36 +00:00
script chore: make USE_LAKE the default (#10016) 2025-08-21 11:43:25 +00:00
src feat: ac normalization in grind (#10146) 2025-08-27 03:28:30 +00:00
stage0 chore: update stage0 2025-08-26 17:42:03 +00:00
tests feat: ac normalization in grind (#10146) 2025-08-27 03:28:30 +00:00
.gitattributes
.gitignore feat: further release automation (#9092) 2025-06-30 05:44:10 +00:00
.gitpod.Dockerfile chore: add gitpod configuration (#6382) 2024-12-15 21:38:13 +00:00
.gitpod.yml chore: add gitpod configuration (#6382) 2024-12-15 21:38:13 +00:00
.ignore
CMakeLists.txt chore: make USE_LAKE the default (#10016) 2025-08-21 11:43:25 +00:00
CMakePresets.json chore: fix reldebug preset (#8051) 2025-04-23 10:05:11 +00:00
CODEOWNERS chore: make datokrat code owner for iterators, ranges and slices (#9667) 2025-08-01 17:34:43 +00:00
CONTRIBUTING.md doc: triage 2024-07-26 18:24:06 +02:00
flake.lock chore: robustify Nix shell (#8141) 2025-04-28 15:08:32 +00:00
flake.nix chore: remove broken Nix build (#9910) 2025-08-14 08:31:39 +00:00
lean-toolchain doc: VS Code dev setup (#2961) 2023-11-30 08:35:03 +00:00
lean.code-workspace chore: add the lean4 extension to the vscode workspace (#3059) 2023-12-14 08:58:21 +00:00
LICENSE
LICENSES feat: ship cadical (#4325) 2024-08-23 09:13:27 +00:00
README.md doc: fix examples link 2025-08-22 16:28:01 +02:00
RELEASES.md chore: updates to release_checklist.md (#7817) 2025-04-04 03:45:36 +00:00

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