Lean 4 fork for HoTT-compatible kernel extensions (Path types, transport, HITs). Maintained against upstream leanprover/lean4.
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Kim Morrison e01cbf2b8f
feat: add structured TraceResult to TraceData (#12698)
This PR adds a `result? : Option TraceResult` field to `TraceData` and
populates it in `withTraceNode` and `withTraceNodeBefore`, so that
metaprograms walking trace trees can determine success/failure
structurally instead of string-matching on emoji.

`TraceResult` has three cases: `.success` (checkEmoji), `.failure`
(crossEmoji), and `.error` (bombEmoji, exception thrown). An
`ExceptToTraceResult` typeclass converts `Except` results to
`TraceResult` directly, with instances for `Bool` and `Option`.
`TraceResult.toEmoji` converts back to emoji for display. This replaces
the previous `ExceptToEmoji` typeclass — `TraceResult` is now the
primary representation rather than being derived from emoji strings.

`withTraceNodeBefore` (used by `isDefEq`) uses
`ExceptToTraceResult.toTraceResult` directly, correctly handling `Bool`
(`.ok false` = failure) and `Option` (`.ok none` = failure), with
`Except.error` mapping to `.error`.

For `withTraceNode`, `result?` defaults to `none`. Callers can pass
`mkResult?` to provide structured results; when set, the corresponding
emoji is auto-prepended to the message.

Motivated by mathlib's `#defeq_abuse` diagnostic tactic
(https://github.com/leanprover-community/mathlib4/pull/35750) which
currently string-matches on emoji to determine trace node outcomes. See
https://leanprover.zulipchat.com/#narrow/channel/113488-general/topic/backward.2EisDefEq.2ErespectTransparency

🤖 Prepared with Claude Code

---------

Co-authored-by: Claude Opus 4.6 <noreply@anthropic.com>
2026-03-10 02:42:57 +00:00
.claude chore: improve CI failure reporting in release checklist (#12786) 2026-03-04 11:55:34 +00:00
.github fix: address unused simp theorem warnings (#12829) 2026-03-06 23:12:03 +00:00
.vscode chore: replace workspace file with .vscode/ settings (#12770) 2026-03-04 01:10:04 +00:00
doc chore: migrate more tests to new test suite (#12809) 2026-03-06 16:52:01 +00:00
images
releases_drafts chore: remove stale release draft notes (#12518) 2026-02-17 19:56:23 +00:00
script feat: unify name demangling with single Lean implementation (#12539) 2026-03-06 12:29:35 +00:00
src feat: add structured TraceResult to TraceData (#12698) 2026-03-10 02:42:57 +00:00
stage0 chore: turn on new do elaborator in Core (#12656) 2026-03-09 12:38:33 +00:00
tests feat: add structured TraceResult to TraceData (#12698) 2026-03-10 02:42:57 +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: add gitpod configuration (#6382) 2024-12-15 21:38:13 +00:00
.ignore chore: ignore stage0/ (for rg etc.) 2022-03-18 15:28:20 +01:00
CMakeLists.txt feat: bundle leantar with Lean (#12822) 2026-03-09 20:10:59 +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
LICENSE chore: remove LICENSE header that confused GitHub 2021-11-18 09:42:35 +01:00
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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