Lean 4 fork for HoTT-compatible kernel extensions (Path types, transport, HITs). Maintained against upstream leanprover/lean4.
Find a file
Leonardo de Moura df61abb08f
fix: normalize instance argument in getStuckMVar? for class projections (#12778)
This PR fixes an inconsistency in `getStuckMVar?` where the instance
argument to class projection functions and auxiliary parent projections
was not whnf-normalized before checking for stuck metavariables. Every
other case in `getStuckMVar?` (recursors, quotient recursors, `.proj`
nodes) normalizes the major argument via `whnf` before recursing — class
projection functions and aux parent projections were the exception.

This bug was identified by Matthew Jasper. When the instance parameter
to a class projection is not normalized, `getStuckMVar?` may fail to
detect stuck metavariables that would be revealed by whnf, or conversely
may report stuckness for expressions that would reduce to constructors.
This caused issues with `OfNat` and `Zero` at
`with_reducible_and_instances` transparency.

Note: PR #12701 (already merged) is also required to fix the original
Mathlib examples.
2026-03-03 18:31:39 +00:00
.claude doc: add guidance on waiting for CI/merges in release command (#12755) 2026-03-02 02:49:34 +00:00
.github fix: use pull_request_target for label-triggered workflows (#12638) 2026-03-01 19:20:56 +11:00
doc chore: switch to new test/bench suite (#12590) 2026-02-25 13:51:53 +00:00
images
releases_drafts chore: remove stale release draft notes (#12518) 2026-02-17 19:56:23 +00:00
script chore: fix profiler shebang and add profiling skill (#12519) 2026-03-01 07:09:33 +00:00
src fix: normalize instance argument in getStuckMVar? for class projections (#12778) 2026-03-03 18:31:39 +00:00
stage0 chore: update stage0 2026-03-02 22:42:13 +00:00
tests feat: lemmas about String.find? and String.contains (#12777) 2026-03-03 16:30:34 +00:00
.gitattributes doc: grove: update and add String data (#11551) 2025-12-08 16:49:37 +00:00
.gitignore chore: fix ci for new test suite (#12704) 2026-02-27 23:25:37 +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: fail build on non-make generators (#12690) 2026-02-25 13:59:40 +00:00
CMakePresets.json chore: fix ci for new test suite (#12704) 2026-02-27 23:25:37 +00:00
CODEOWNERS chore: make @hargoniX code owner of the compiler (#10732) 2025-10-10 04:43:38 +00:00
CONTRIBUTING.md doc: triage 2024-07-26 18:24:06 +02:00
flake.lock chore: update to c++20 (#12117) 2026-02-11 01:17:40 +00:00
flake.nix chore: update to c++20 (#12117) 2026-02-11 01:17:40 +00:00
lean-toolchain chore: relative lean-toolchains (#12652) 2026-02-25 10:23:35 +00:00
lean.code-workspace chore: relative lean-toolchains (#12652) 2026-02-25 10:23:35 +00:00
LICENSE
LICENSES feat: ship cadical (#4325) 2024-08-23 09:13:27 +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

This is the repository for Lean 4.

About

Installation

See Install Lean.

Contributing

Please read our Contribution Guidelines first.

Building from Source

See Building Lean.