Lean 4 fork for HoTT-compatible kernel extensions (Path types, transport, HITs). Maintained against upstream leanprover/lean4.
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Joachim Breitner 861f722844
fix: handle multi-discriminant casesOn in WF unfold equation generation (#13232)
This PR fixes a panic when compiling mutually recursive definitions that
use `casesOn` on indexed inductive types (e.g. `Vect`). The
`splitMatchOrCasesOn` function in `WF.Unfold` asserted
`matcherInfo.numDiscrs = 1`, but for indexed types the casesOn recursor
has multiple discriminants (indices + major premise). The fix uses the
last discriminant (the major premise) and lets the `cases` tactic handle
index discriminants automatically.

Closes #13015

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

Co-authored-by: Claude Opus 4.6 <noreply@anthropic.com>
2026-04-01 15:23:13 +00:00
.claude chore: add safety notes to release command (#13225) 2026-04-01 05:01:00 +00:00
.github fix: make -DLEAN_VERSION_* CMake overrides actually work (#13226) 2026-04-01 05:31:23 +00:00
.vscode chore: replace workspace file with .vscode/ settings (#12770) 2026-03-04 01:10:04 +00:00
doc chore: strip binaries only in release builds (#13208) 2026-03-31 17:18:43 +00:00
images
releases_drafts chore: remove stale release draft notes (#12518) 2026-02-17 19:56:23 +00:00
script fix: make -DLEAN_VERSION_* CMake overrides actually work (#13226) 2026-04-01 05:31:23 +00:00
src fix: handle multi-discriminant casesOn in WF unfold equation generation (#13232) 2026-04-01 15:23:13 +00:00
stage0 chore: update stage0 2026-04-01 12:56:25 +00:00
tests fix: handle multi-discriminant casesOn in WF unfold equation generation (#13232) 2026-04-01 15:23:13 +00:00
.gitattributes chore: migrate more tests to new test suite (#12809) 2026-03-06 16:52:01 +00:00
.gitignore chore: replace workspace file with .vscode/ settings (#12770) 2026-03-04 01:10:04 +00:00
.gitpod.Dockerfile chore: add gitpod configuration (#6382) 2024-12-15 21:38:13 +00:00
.gitpod.yml chore: strip binaries only in release builds (#13208) 2026-03-31 17:18:43 +00:00
.ignore
CMakeLists.txt chore: use FetchContent for mimalloc source acquisition (#13196) 2026-03-31 18:00:39 +00:00
CMakePresets.json chore: strip binaries only in release builds (#13208) 2026-03-31 17:18:43 +00:00
CODEOWNERS chore: make @hargoniX code owner of the compiler (#10732) 2025-10-10 04:43:38 +00:00
CONTRIBUTING.md chore: migrate pkg tests (#12889) 2026-03-11 18:55:46 +00:00
flake.lock chore: update to c++20 (#12117) 2026-02-11 01:17:40 +00:00
flake.nix chore: add aarch64-darwin to flake (#12915) 2026-03-18 15:55:34 +00:00
lean-toolchain chore: relative lean-toolchains (#12652) 2026-02-25 10:23:35 +00:00
LICENSE
LICENSES feat: bundle leantar with Lean (#12822) 2026-03-09 20:10:59 +00:00
README.md doc: update URLs that are currently pointing to redirects (#10397) 2025-09-17 15:50:07 +00:00
RELEASES.md chore: updates to release_checklist.md (#7817) 2025-04-04 03:45:36 +00:00

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