Lean 4 fork for HoTT-compatible kernel extensions (Path types, transport, HITs). Maintained against upstream leanprover/lean4.
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Sebastian Ullrich 8f80881c2f
feat: idbg interactive debug expression evaluator (#12648)
This PR adds the experimental `idbg e`, a new do-element (and term)
syntax for live debugging between the language server and a running
compiled Lean program.

When placed in a `do` block, `idbg` captures all local variables in
scope and expression `e`, then:

- **In the language server**: starts a TCP server on localhost waiting
for the running program to
connect; the editor will mark this part of the program as "in progress"
during this wait but that
  will not block `lake build` of the project.
- **In the compiled program**: on first execution of the `idbg` call
site, connects to the server,
receives the expression, compiles and evaluates it using the program's
actual runtime values, and
  sends the `repr` result back.

The result is displayed as an info diagnostic on the `idbg` keyword. The
expression `e` can be
edited while the program is running - each edit triggers re-elaboration
of `e`, a new TCP exchange,
and an updated result. This makes `idbg` a live REPL for inspecting and
experimenting with
program state at a specific point in execution. Only when `idbg` is
inserted, moved, or removed does
the program need to be recompiled and restarted.

# Known Limitations

* The program will poll for the server for up to 10 minutes and needs to
be killed manually
  otherwise.
* Use of multiple `idbg` at once untested, likely too much overhead from
overlapping imports without
  further changes.
* `LEAN_PATH` must be properly set up so compiled program can import its
origin module.
* Untested on Windows and macOS.
2026-02-23 17:22:44 +00:00
.claude chore: CLAUDE.md: restrict build parallelism (#12624) 2026-02-22 14:35:05 +00:00
.github feat: lazy initialization of closed terms (#12044) 2026-02-20 08:45:15 +00:00
doc chore: improve release command PR status checking (#12536) 2026-02-17 21:21:30 +00:00
images
releases_drafts chore: remove stale release draft notes (#12518) 2026-02-17 19:56:23 +00:00
script fix: update bump branch toolchain to nightly for all repos (#12586) 2026-02-19 13:04:26 +00:00
src feat: idbg interactive debug expression evaluator (#12648) 2026-02-23 17:22:44 +00:00
stage0 chore: update stage0 2026-02-23 04:20:25 +00:00
tests feat: idbg interactive debug expression evaluator (#12648) 2026-02-23 17:22:44 +00:00
.gitattributes doc: grove: update and add String data (#11551) 2025-12-08 16:49:37 +00:00
.gitignore chore: enable leanprover/skills plugin for Claude Code (#12609) 2026-02-20 12:35:32 +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: fix repeated cmake calls breaking the build (#12598) 2026-02-19 16:23:47 +00:00
CMakePresets.json chore: CI: enable leak sanitizer again (#11339) 2025-11-27 18:32:35 +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
lean.code-workspace chore: lean.code-workspace: fix terminal cwd (#10802) 2025-10-16 20:19:12 +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

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