feat: add user-defined fallback procedure for the grind tactic

This PR introduces support for user-defined fallback code in the
`grind` tactic. The fallback code can be utilized to inspect the state
of failing `grind` subgoals and/or invoke user-defined
automation. Users can now write `grind on_failure <code>`, where
`<code>` should have the type `GoalM Unit`. See the modified tests in
this PR for examples.

doc/dev/commit_convention.md

@@ -33,9 +33,6 @@ Format of the commit message
  - chore (maintain, ex: travis-ci)
  - perf (performance improvement, optimization, ...)
 
-Every `feat` or `fix` commit must have a `changelog-*` label, and a commit message
-beginning with "This PR " that will be included in the changelog.
-
 ``<subject>`` has the following constraints:
 
  - use imperative, present tense: "change" not "changed" nor "changes"
@@ -47,7 +44,6 @@ beginning with "This PR " that will be included in the changelog.
  - just as in ``<subject>``, use imperative, present tense
  - includes motivation for the change and contrasts with previous
    behavior
- - If a `changelog-*` label is present, the body must begin with "This PR ".
 
 ``<footer>`` is optional and may contain two items:
 
@@ -64,21 +60,17 @@ Examples
 
 fix: add declarations for operator<<(std::ostream&, expr const&) and operator<<(std::ostream&, context const&) in the kernel
 
-This PR adds declarations `operator<<` for raw printing.
 The actual implementation of these two operators is outside of the
-kernel. They are implemented in the file 'library/printer.cpp'.
-
-We declare them in the kernel to prevent the following problem.
-Suppose there is a file 'foo.cpp' that does not include 'library/printer.h',
+kernel. They are implemented in the file 'library/printer.cpp'. We
+declare them in the kernel to prevent the following problem. Suppose
+there is a file 'foo.cpp' that does not include 'library/printer.h',
 but contains
-```cpp
-expr a;
-...
-std::cout << a << "\n";
-...
-```
+
+    expr a;
+    ...
+    std::cout << a << "\n";
+    ...
 
 The compiler does not generate an error message. It silently uses the
 operator bool() to coerce the expression into a Boolean. This produces
 counter-intuitive behavior, and may confuse developers.
-

doc/dev/ffi.md

@@ -49,9 +49,8 @@ In the case of `@[extern]` all *irrelevant* types are removed first; see next se
   is represented by the representation of that parameter's type.
 
   For example, `{ x : α // p }`, the `Subtype` structure of a value of type `α` and an irrelevant proof, is represented by the representation of `α`.
-  Similarly, the signed integer types `Int8`, ..., `Int64`, `ISize` are also represented by the unsigned C types `uint8_t`, ..., `uint64_t`, `size_t`, respectively, because they have a trivial structure.
-* `Nat` and `Int` are represented by `lean_object *`.
-  Their runtime values is either a pointer to an opaque bignum object or, if the lowest bit of the "pointer" is 1 (`lean_is_scalar`), an encoded unboxed natural number or integer (`lean_box`/`lean_unbox`).
+* `Nat` is represented by `lean_object *`.
+  Its runtime value is either a pointer to an opaque bignum object or, if the lowest bit of the "pointer" is 1 (`lean_is_scalar`), an encoded unboxed natural number (`lean_box`/`lean_unbox`).
 * A universe `Sort u`, type constructor `... → Sort u`, or proposition `p : Prop` is *irrelevant* and is either statically erased (see above) or represented as a `lean_object *` with the runtime value `lean_box(0)`
 * Any other type is represented by `lean_object *`.
   Its runtime value is a pointer to an object of a subtype of `lean_object` (see the "Inductive types" section below) or the unboxed value `lean_box(cidx)` for the `cidx`th constructor of an inductive type if this constructor does not have any relevant parameters.

doc/dev/index.md

@@ -80,10 +80,3 @@ Unlike most Lean projects, all submodules of the `Lean` module begin with the
 `prelude` keyword. This disables the automated import of `Init`, meaning that
 developers need to figure out their own subset of `Init` to import. This is done
 such that changing files in `Init` doesn't force a full rebuild of `Lean`.
-
-### Testing against Mathlib/Batteries
-You can test a Lean PR against Mathlib and Batteries by rebasing your PR
-on to `nightly-with-mathlib` branch. (It is fine to force push after rebasing.)
-CI will generate a branch of Mathlib and Batteries called `lean-pr-testing-NNNN`
-that uses the toolchain for your PR, and will report back to the Lean PR with results from Mathlib CI.
-See https://leanprover-community.github.io/contribute/tags_and_branches.html for more details.

doc/dev/release_checklist.md

@@ -5,6 +5,11 @@ See below for the checklist for release candidates.
 
 We'll use `v4.6.0` as the intended release version as a running example.
 
+- One week before the planned release, ensure that
+  (1) someone has written the release notes and
+  (2) someone has written the first draft of the release blog post.
+  If there is any material in `./releases_drafts/` on the `releases/v4.6.0` branch, then the release notes are not done.
+  (See the section "Writing the release notes".)
 - `git checkout releases/v4.6.0`
   (This branch should already exist, from the release candidates.)
 - `git pull`
@@ -37,32 +42,16 @@ We'll use `v4.6.0` as the intended release version as a running example.
     - Create the tag `v4.6.0` from `master`/`main` and push it.
     - Merge the tag `v4.6.0` into the `stable` branch and push it.
   - We do this for the repositories:
-    - [Batteries](https://github.com/leanprover-community/batteries)
-      - No dependencies
-      - Toolchain bump PR
-      - Create and push the tag
-      - Merge the tag into `stable`
     - [lean4checker](https://github.com/leanprover/lean4checker)
       - No dependencies
       - Toolchain bump PR
       - Create and push the tag
       - Merge the tag into `stable`
-    - [doc-gen4](https://github.com/leanprover/doc-gen4)
-      - Dependencies: exist, but they're not part of the release workflow
-      - Toolchain bump PR including updated Lake manifest
-      - Create and push the tag
-      - There is no `stable` branch; skip this step
-    - [Verso](https://github.com/leanprover/verso)
-      - Dependencies: exist, but they're not part of the release workflow
-      - The `SubVerso` dependency should be compatible with _every_ Lean release simultaneously, rather than following this workflow
-      - Toolchain bump PR including updated Lake manifest
-      - Create and push the tag
-      - There is no `stable` branch; skip this step
-    - [Cli](https://github.com/leanprover/lean4-cli)
+    - [Batteries](https://github.com/leanprover-community/batteries)
       - No dependencies
       - Toolchain bump PR
       - Create and push the tag
-      - There is no `stable` branch; skip this step
+      - Merge the tag into `stable`
     - [ProofWidgets4](https://github.com/leanprover-community/ProofWidgets4)
       - Dependencies: `Batteries`
       - Note on versions and branches:
@@ -77,11 +66,18 @@ We'll use `v4.6.0` as the intended release version as a running example.
       - Toolchain bump PR including updated Lake manifest
       - Create and push the tag
       - Merge the tag into `stable`
-    - [import-graph](https://github.com/leanprover-community/import-graph)
+    - [doc-gen4](https://github.com/leanprover/doc-gen4)
+      - Dependencies: exist, but they're not part of the release workflow
       - Toolchain bump PR including updated Lake manifest
       - Create and push the tag
       - There is no `stable` branch; skip this step
-    - [plausible](https://github.com/leanprover-community/plausible)
+    - [Verso](https://github.com/leanprover/verso)
+      - Dependencies: exist, but they're not part of the release workflow
+      - The `SubVerso` dependency should be compatible with _every_ Lean release simultaneously, rather than following this workflow
+      - Toolchain bump PR including updated Lake manifest
+      - Create and push the tag
+      - There is no `stable` branch; skip this step
+    - [import-graph](https://github.com/leanprover-community/import-graph)
       - Toolchain bump PR including updated Lake manifest
       - Create and push the tag
       - There is no `stable` branch; skip this step
@@ -90,7 +86,7 @@ We'll use `v4.6.0` as the intended release version as a running example.
       - Toolchain bump PR notes:
         - In addition to updating the `lean-toolchain` and `lakefile.lean`,
           in `.github/workflows/lean4checker.yml` update the line
-          `git checkout v4.6.0` to the appropriate tag.
+          `git checkout v4.6.0` to the appropriate tag. 
         - Push the PR branch to the main Mathlib repository rather than a fork, or CI may not work reliably
         - Create and push the tag
         - Create a new branch from the tag, push it, and open a pull request against `stable`.
@@ -102,7 +98,6 @@ We'll use `v4.6.0` as the intended release version as a running example.
       - Toolchain bump PR including updated Lake manifest
       - Create and push the tag
       - Merge the tag into `stable`
-- Run `scripts/release_checklist.py v4.6.0` to check that everything is in order.
 - The `v4.6.0` section of `RELEASES.md` is out of sync between
   `releases/v4.6.0` and `master`. This should be reconciled:
   - Replace the `v4.6.0` section on `master` with the `v4.6.0` section on `releases/v4.6.0`
@@ -144,13 +139,16 @@ We'll use `v4.7.0-rc1` as the intended release version in this example.
     git checkout -b releases/v4.7.0
     ```
 - In `RELEASES.md` replace `Development in progress` in the `v4.7.0` section with `Release notes to be written.`
-- It is essential to choose the nightly that will become the release candidate as early as possible, to avoid confusion.
+- We will rely on automatically generated release notes for release candidates,
+  and the written release notes will be used for stable versions only.
+  It is essential to choose the nightly that will become the release candidate as early as possible, to avoid confusion.
 - In `src/CMakeLists.txt`,
   - verify that you see `set(LEAN_VERSION_MINOR 7)` (for whichever `7` is appropriate); this should already have been updated when the development cycle began.
   - `set(LEAN_VERSION_IS_RELEASE 1)` (this should be a change; on `master` and nightly releases it is always `0`).
   - Commit your changes to `src/CMakeLists.txt`, and push.
 - `git tag v4.7.0-rc1`
 - `git push origin v4.7.0-rc1`
+- Ping the FRO Zulip that release notes need to be written. The release notes do not block completing the rest of this checklist.
 - Now wait, while CI runs.
   - You can monitor this at `https://github.com/leanprover/lean4/actions/workflows/ci.yml`, looking for the `v4.7.0-rc1` tag.
   - This step can take up to an hour.
@@ -250,12 +248,15 @@ Please read https://leanprover-community.github.io/contribute/tags_and_branches.
 
 # Writing the release notes
 
-Release notes are automatically generated from the commit history, using `script/release_notes.py`.
+We are currently trying a system where release notes are compiled all at once from someone looking through the commit history.
+The exact steps are a work in progress.
+Here is the general idea:
 
-Run this as `script/release_notes.py v4.6.0`, where `v4.6.0` is the *previous* release version. This will generate output
-for all commits since that tag. Note that there is output on both stderr, which should be manually reviewed,
-and on stdout, which should be manually copied to `RELEASES.md`.
-
-There can also be pre-written entries in `./releases_drafts`, which should be all incorporated in the release notes and then deleted from the branch.
+* The work is done right on the `releases/v4.6.0` branch sometime after it is created but before the stable release is made.
+  The release notes for `v4.6.0` will later be copied to `master` when we begin a new development cycle.
+* There can be material for release notes entries in commit messages.
+* There can also be pre-written entries in `./releases_drafts`, which should be all incorporated in the release notes and then deleted from the branch.
   See `./releases_drafts/README.md` for more information.
+* The release notes should be written from a downstream expert user's point of view.
 
+This section will be updated when the next release notes are written (for `v4.10.0`).

releases_drafts/list_lex.md

@@ -0,0 +1,16 @@
+We replace the inductive predicate `List.lt` with an upstreamed version of `List.Lex` from Mathlib.
+(Previously `Lex.lt` was defined in terms of `<`; now it is generalized to take an arbitrary relation.)
+This subtely changes the notion of ordering on `List α`.
+
+`List.lt` was a weaker relation: in particular if `l₁ < l₂`, then
+`a :: l₁ < b :: l₂` may hold according to `List.lt` even if `a` and `b` are merely incomparable
+(either neither `a < b` nor `b < a`), whereas according to `List.Lex` this would require `a = b`.
+
+When `<` is total, in the sense that `¬ · < ·` is antisymmetric, then the two relations coincide.
+
+Mathlib was already overriding the order instances for `List α`,
+so this change should not be noticed by anyone already using Mathlib.
+
+We simultaneously add the boolean valued `List.lex` function, parameterised by a `BEq` typeclass
+and an arbitrary `lt` function. This will support the flexibility previously provided for `List.lt`,
+via a `==` function which is weaker than strict equality.

script/prepare-llvm-linux.sh

@@ -63,8 +63,8 @@ else
 fi
 # use `-nostdinc` to make sure headers are not visible by default (in particular, not to `#include_next` in the clang headers),
 # but do not change sysroot so users can still link against system libs
-echo -n " -DLEANC_INTERNAL_FLAGS='--sysroot ROOT -nostdinc -isystem ROOT/include/clang' -DLEANC_CC=ROOT/bin/clang"
-echo -n " -DLEANC_INTERNAL_LINKER_FLAGS='--sysroot ROOT -L ROOT/lib -L ROOT/lib/glibc ROOT/lib/glibc/libc_nonshared.a ROOT/lib/glibc/libpthread_nonshared.a -Wl,--as-needed -Wl,-Bstatic -lgmp -lunwind -luv -Wl,-Bdynamic -Wl,--no-as-needed -fuse-ld=lld'"
+echo -n " -DLEANC_INTERNAL_FLAGS='-nostdinc -isystem ROOT/include/clang' -DLEANC_CC=ROOT/bin/clang"
+echo -n " -DLEANC_INTERNAL_LINKER_FLAGS='-L ROOT/lib -L ROOT/lib/glibc ROOT/lib/glibc/libc_nonshared.a ROOT/lib/glibc/libpthread_nonshared.a -Wl,--as-needed -Wl,-Bstatic -lgmp -lunwind -luv -Wl,-Bdynamic -Wl,--no-as-needed -fuse-ld=lld'"
 # when not using the above flags, link GMP dynamically/as usual
 echo -n " -DLEAN_EXTRA_LINKER_FLAGS='-Wl,--as-needed -lgmp -luv -lpthread -ldl -lrt -Wl,--no-as-needed'"
 # do not set `LEAN_CC` for tests

script/prepare-llvm-macos.sh

@@ -48,11 +48,12 @@ if [[ -L llvm-host ]]; then
   echo -n " -DCMAKE_C_COMPILER=$PWD/stage1/bin/clang"
   gcp $GMP/lib/libgmp.a stage1/lib/
   gcp $LIBUV/lib/libuv.a stage1/lib/
+  echo -n " -DLEANC_INTERNAL_LINKER_FLAGS='-L ROOT/lib -L ROOT/lib/libc -fuse-ld=lld'"
   echo -n " -DLEAN_EXTRA_LINKER_FLAGS='-lgmp -luv'"
 else
   echo -n " -DCMAKE_C_COMPILER=$PWD/llvm-host/bin/clang -DLEANC_OPTS='--sysroot $PWD/stage1 -resource-dir $PWD/stage1/lib/clang/15.0.1 ${EXTRA_FLAGS:-}'"
+  echo -n " -DLEANC_INTERNAL_LINKER_FLAGS='-L ROOT/lib -L ROOT/lib/libc -fuse-ld=lld'"
 fi
-echo -n " -DLEANC_INTERNAL_FLAGS='--sysroot ROOT -nostdinc -isystem ROOT/include/clang' -DLEANC_CC=ROOT/bin/clang"
-echo -n " -DLEANC_INTERNAL_LINKER_FLAGS='--sysroot ROOT -L ROOT/lib -L ROOT/lib/libc -fuse-ld=lld'"
+echo -n " -DLEANC_INTERNAL_FLAGS='-nostdinc -isystem ROOT/include/clang' -DLEANC_CC=ROOT/bin/clang"
 # do not set `LEAN_CC` for tests
 echo -n " -DLEAN_TEST_VARS=''"

script/prepare-llvm-mingw.sh

@@ -43,7 +43,7 @@ echo -n " -DCMAKE_C_COMPILER=$PWD/stage1/bin/clang.exe -DCMAKE_C_COMPILER_WORKS=
 echo -n " -DSTAGE0_CMAKE_C_COMPILER=clang -DSTAGE0_CMAKE_CXX_COMPILER=clang++"
 echo -n " -DLEAN_EXTRA_CXX_FLAGS='--sysroot $PWD/llvm -idirafter /clang64/include/'"
 echo -n " -DLEANC_INTERNAL_FLAGS='--sysroot ROOT -nostdinc -isystem ROOT/include/clang' -DLEANC_CC=ROOT/bin/clang.exe"
-echo -n " -DLEANC_INTERNAL_LINKER_FLAGS='--sysroot ROOT -L ROOT/lib -Wl,-Bstatic -lgmp $(pkg-config --static --libs libuv) -lunwind -Wl,-Bdynamic -fuse-ld=lld'"
+echo -n " -DLEANC_INTERNAL_LINKER_FLAGS='-L ROOT/lib -static-libgcc -Wl,-Bstatic -lgmp $(pkg-config --static --libs libuv) -lunwind -Wl,-Bdynamic -fuse-ld=lld'"
 # when not using the above flags, link GMP dynamically/as usual. Always link ICU dynamically.
 echo -n " -DLEAN_EXTRA_LINKER_FLAGS='-lgmp $(pkg-config --libs libuv) -lucrtbase'"
 # do not set `LEAN_CC` for tests

script/release_checklist.py

@@ -1,132 +0,0 @@
-#!/usr/bin/env python3
-
-import argparse
-import yaml
-import requests
-import base64
-import subprocess
-import sys
-import os
-
-def parse_repos_config(file_path):
-    with open(file_path, "r") as f:
-        return yaml.safe_load(f)["repositories"]
-
-def get_github_token():
-    try:
-        import subprocess
-        result = subprocess.run(['gh', 'auth', 'token'], capture_output=True, text=True)
-        if result.returncode == 0:
-            return result.stdout.strip()
-    except FileNotFoundError:
-        print("Warning: 'gh' CLI not found. Some API calls may be rate-limited.")
-    return None
-
-def get_branch_content(repo_url, branch, file_path, github_token):
-    api_url = repo_url.replace("https://github.com/", "https://api.github.com/repos/") + f"/contents/{file_path}?ref={branch}"
-    headers = {'Authorization': f'token {github_token}'} if github_token else {}
-    response = requests.get(api_url, headers=headers)
-    if response.status_code == 200:
-        content = response.json().get("content", "")
-        content = content.replace("\n", "")
-        try:
-            return base64.b64decode(content).decode('utf-8').strip()
-        except Exception:
-            return None
-    return None
-
-def tag_exists(repo_url, tag_name, github_token):
-    api_url = repo_url.replace("https://github.com/", "https://api.github.com/repos/") + f"/git/refs/tags/{tag_name}"
-    headers = {'Authorization': f'token {github_token}'} if github_token else {}
-    response = requests.get(api_url, headers=headers)
-    return response.status_code == 200
-
-def is_merged_into_stable(repo_url, tag_name, stable_branch, github_token):
-    # First get the commit SHA for the tag
-    api_base = repo_url.replace("https://github.com/", "https://api.github.com/repos/")
-    headers = {'Authorization': f'token {github_token}'} if github_token else {}
-
-    # Get tag's commit SHA
-    tag_response = requests.get(f"{api_base}/git/refs/tags/{tag_name}", headers=headers)
-    if tag_response.status_code != 200:
-        return False
-    tag_sha = tag_response.json()['object']['sha']
-
-    # Get commits on stable branch containing this SHA
-    commits_response = requests.get(
-        f"{api_base}/commits?sha={stable_branch}&per_page=100",
-        headers=headers
-    )
-    if commits_response.status_code != 200:
-        return False
-
-    # Check if any commit in stable's history matches our tag's SHA
-    stable_commits = [commit['sha'] for commit in commits_response.json()]
-    return tag_sha in stable_commits
-
-def parse_version(version_str):
-    # Remove 'v' prefix and split into components
-    # Handle Lean toolchain format (leanprover/lean4:v4.x.y)
-    if ':' in version_str:
-        version_str = version_str.split(':')[1]
-    version = version_str.lstrip('v')
-    # Handle release candidates by removing -rc part for comparison
-    version = version.split('-')[0]
-    return tuple(map(int, version.split('.')))
-
-def is_version_gte(version1, version2):
-    """Check if version1 >= version2"""
-    return parse_version(version1) >= parse_version(version2)
-
-def is_release_candidate(version):
-    return "-rc" in version
-
-def main():
-    github_token = get_github_token()
-
-    if len(sys.argv) != 2:
-        print("Usage: python3 release_checklist.py <toolchain>")
-        sys.exit(1)
-
-    toolchain = sys.argv[1]
-
-    with open(os.path.join(os.path.dirname(__file__), "release_repos.yml")) as f:
-        repos = yaml.safe_load(f)["repositories"]
-
-    for repo in repos:
-        name = repo["name"]
-        url = repo["url"]
-        branch = repo["branch"]
-        check_stable = repo["stable-branch"]
-        check_tag = repo.get("toolchain-tag", True)
-
-        print(f"\nRepository: {name}")
-
-        # Check if branch is on at least the target toolchain
-        lean_toolchain_content = get_branch_content(url, branch, "lean-toolchain", github_token)
-        if lean_toolchain_content is None:
-            print(f"  ❌ No lean-toolchain file found in {branch} branch")
-            continue
-
-        on_target_toolchain = is_version_gte(lean_toolchain_content.strip(), toolchain)
-        if not on_target_toolchain:
-            print(f"  ❌ Not on target toolchain (needs ≥ {toolchain}, but {branch} is on {lean_toolchain_content.strip()})")
-            continue
-        print(f"  ✅ On compatible toolchain (>= {toolchain})")
-
-        # Only check for tag if toolchain-tag is true
-        if check_tag:
-            if not tag_exists(url, toolchain, github_token):
-                print(f"  ❌ Tag {toolchain} does not exist")
-                continue
-            print(f"  ✅ Tag {toolchain} exists")
-
-        # Only check merging into stable if stable-branch is true and not a release candidate
-        if check_stable and not is_release_candidate(toolchain):
-            if not is_merged_into_stable(url, toolchain, "stable", github_token):
-                print(f"  ❌ Tag {toolchain} is not merged into stable")
-                continue
-            print(f"  ✅ Tag {toolchain} is merged into stable")
-
-if __name__ == "__main__":
-    main()

script/release_notes.py

@@ -1,145 +0,0 @@
-#!/usr/bin/env python3
-
-import sys
-import re
-import json
-import requests
-import subprocess
-from collections import defaultdict
-from git import Repo
-
-def get_commits_since_tag(repo, tag):
-    try:
-        tag_commit = repo.commit(tag)
-        commits = list(repo.iter_commits(f"{tag_commit.hexsha}..HEAD"))
-        return [
-            (commit.hexsha, commit.message.splitlines()[0], commit.message)
-            for commit in commits
-        ]
-    except Exception as e:
-        sys.stderr.write(f"Error retrieving commits: {e}\n")
-        sys.exit(1)
-
-def check_pr_number(first_line):
-    match = re.search(r"\(\#(\d+)\)$", first_line)
-    if match:
-        return int(match.group(1))
-    return None
-
-def fetch_pr_labels(pr_number):
-    try:
-        # Use gh CLI to fetch PR details
-        result = subprocess.run([
-            "gh", "api", f"repos/leanprover/lean4/pulls/{pr_number}"
-        ], capture_output=True, text=True, check=True)
-        pr_data = result.stdout
-        pr_json = json.loads(pr_data)
-        return [label["name"] for label in pr_json.get("labels", [])]
-    except subprocess.CalledProcessError as e:
-        sys.stderr.write(f"Failed to fetch PR #{pr_number} using gh: {e.stderr}\n")
-        return []
-
-def format_section_title(label):
-    title = label.replace("changelog-", "").capitalize()
-    if title == "Doc":
-        return "Documentation"
-    elif title == "Pp":
-        return "Pretty Printing"
-    return title
-
-def sort_sections_order():
-    return [
-        "Language",
-        "Library",
-        "Compiler",
-        "Pretty Printing",
-        "Documentation",
-        "Server",
-        "Lake",
-        "Other",
-        "Uncategorised"
-    ]
-
-def format_markdown_description(pr_number, description):
-    link = f"[#{pr_number}](https://github.com/leanprover/lean4/pull/{pr_number})"
-    return f"{link} {description}"
-
-def main():
-    if len(sys.argv) != 2:
-        sys.stderr.write("Usage: script.py <git-tag>\n")
-        sys.exit(1)
-
-    tag = sys.argv[1]
-    try:
-        repo = Repo(".")
-    except Exception as e:
-        sys.stderr.write(f"Error opening Git repository: {e}\n")
-        sys.exit(1)
-
-    commits = get_commits_since_tag(repo, tag)
-
-    sys.stderr.write(f"Found {len(commits)} commits since tag {tag}:\n")
-    for commit_hash, first_line, _ in commits:
-        sys.stderr.write(f"- {commit_hash}: {first_line}\n")
-
-    changelog = defaultdict(list)
-
-    for commit_hash, first_line, full_message in commits:
-        # Skip commits with the specific first lines
-        if first_line == "chore: update stage0" or first_line.startswith("chore: CI: bump "):
-            continue
-
-        pr_number = check_pr_number(first_line)
-
-        if not pr_number:
-            sys.stderr.write(f"No PR number found in {first_line}\n")
-            continue
-
-        # Remove the first line from the full_message for further processing
-        body = full_message[len(first_line):].strip()
-
-        paragraphs = body.split('\n\n')
-        second_paragraph = paragraphs[0] if len(paragraphs) > 0 else ""
-
-        labels = fetch_pr_labels(pr_number)
-
-        # Skip entries with the "changelog-no" label
-        if "changelog-no" in labels:
-            continue
-
-        report_errors = first_line.startswith("feat:") or first_line.startswith("fix:")
-
-        if not second_paragraph.startswith("This PR "):
-            if report_errors:
-                sys.stderr.write(f"No PR description found in commit:\n{commit_hash}\n{first_line}\n{body}\n\n")
-                fallback_description = re.sub(r":$", "", first_line.split(" ", 1)[1]).rsplit(" (#", 1)[0]
-                markdown_description = format_markdown_description(pr_number, fallback_description)
-            else:
-                continue
-        else:
-            markdown_description = format_markdown_description(pr_number, second_paragraph.replace("This PR ", ""))
-
-        changelog_labels = [label for label in labels if label.startswith("changelog-")]
-        if len(changelog_labels) > 1:
-            sys.stderr.write(f"Warning: Multiple changelog-* labels found for PR #{pr_number}: {changelog_labels}\n")
-
-        if not changelog_labels:
-            if report_errors:
-                sys.stderr.write(f"Warning: No changelog-* label found for PR #{pr_number}\n")
-            else:
-                continue
-
-        for label in changelog_labels:
-            changelog[label].append((pr_number, markdown_description))
-
-    section_order = sort_sections_order()
-    sorted_changelog = sorted(changelog.items(), key=lambda item: section_order.index(format_section_title(item[0])) if format_section_title(item[0]) in section_order else len(section_order))
-
-    for label, entries in sorted_changelog:
-        section_title = format_section_title(label) if label != "Uncategorised" else "Uncategorised"
-        print(f"## {section_title}\n")
-        for _, entry in sorted(entries, key=lambda x: x[0]):
-            print(f"* {entry}\n")
-
-if __name__ == "__main__":
-    main()

script/release_repos.yml

@@ -1,86 +0,0 @@
-repositories:
-  - name: Batteries
-    url: https://github.com/leanprover-community/batteries
-    toolchain-tag: true
-    stable-branch: true
-    branch: main
-    dependencies: []
-
-  - name: lean4checker
-    url: https://github.com/leanprover/lean4checker
-    toolchain-tag: true
-    stable-branch: true
-    branch: master
-    dependencies: []
-
-  - name: doc-gen4
-    url: https://github.com/leanprover/doc-gen4
-    toolchain-tag: true
-    stable-branch: false
-    branch: main
-    dependencies: []
-
-  - name: Verso
-    url: https://github.com/leanprover/verso
-    toolchain-tag: true
-    stable-branch: false
-    branch: main
-    dependencies: []
-
-  - name: Cli
-    url: https://github.com/leanprover/lean4-cli
-    toolchain-tag: true
-    stable-branch: false
-    branch: main
-    dependencies: []
-
-  - name: ProofWidgets4
-    url: https://github.com/leanprover-community/ProofWidgets4
-    toolchain-tag: false
-    stable-branch: false
-    branch: main
-    dependencies:
-      - Batteries
-
-  - name: Aesop
-    url: https://github.com/leanprover-community/aesop
-    toolchain-tag: true
-    stable-branch: true
-    branch: master
-    dependencies:
-      - Batteries
-
-  - name: import-graph
-    url: https://github.com/leanprover-community/import-graph
-    toolchain-tag: true
-    stable-branch: false
-    branch: main
-    dependencies: []
-
-  - name: plausible
-    url: https://github.com/leanprover-community/plausible
-    toolchain-tag: true
-    stable-branch: false
-    branch: main
-    dependencies: []
-
-  - name: Mathlib
-    url: https://github.com/leanprover-community/mathlib4
-    toolchain-tag: true
-    stable-branch: true
-    branch: master
-    dependencies:
-      - Aesop
-      - ProofWidgets4
-      - lean4checker
-      - Batteries
-      - doc-gen4
-      - import-graph
-
-  - name: REPL
-    url: https://github.com/leanprover-community/repl
-    toolchain-tag: true
-    stable-branch: true
-    branch: master
-    dependencies:
-      - Mathlib

src/Init/Conv.lean

@@ -150,10 +150,6 @@ See the `simp` tactic for more information. -/
 syntax (name := simp) "simp" optConfig (discharger)? (&" only")?
   (" [" withoutPosition((simpStar <|> simpErase <|> simpLemma),*) "]")? : conv
 
-/-- `simp?` takes the same arguments as `simp`, but reports an equivalent call to `simp only`
-that would be sufficient to close the goal. See the `simp?` tactic for more information. -/
-syntax (name := simpTrace) "simp?" optConfig (discharger)? (&" only")? (simpArgs)? : conv
-
 /--
 `dsimp` is the definitional simplifier in `conv`-mode. It differs from `simp` in that it only
 applies theorems that hold by reflexivity.
@@ -171,9 +167,6 @@ example (a : Nat): (0 + 0) = a - a := by
 syntax (name := dsimp) "dsimp" optConfig (discharger)? (&" only")?
   (" [" withoutPosition((simpErase <|> simpLemma),*) "]")? : conv
 
-@[inherit_doc simpTrace]
-syntax (name := dsimpTrace) "dsimp?" optConfig (&" only")? (dsimpArgs)? : conv
-
 /-- `simp_match` simplifies match expressions. For example,
 ```
 match [a, b] with

src/Init/Data/Array/Basic.lean

@@ -244,7 +244,8 @@ def ofFn {n} (f : Fin n → α) : Array α := go 0 (mkEmpty n) where
 def range (n : Nat) : Array Nat :=
   ofFn fun (i : Fin n) => i
 
-@[inline] protected def singleton (v : α) : Array α := #[v]
+def singleton (v : α) : Array α :=
+  mkArray 1 v
 
 def back! [Inhabited α] (a : Array α) : α :=
   a[a.size - 1]!

src/Init/Data/BitVec/Lemmas.lean

@@ -9,9 +9,7 @@ import Init.Data.Bool
 import Init.Data.BitVec.Basic
 import Init.Data.Fin.Lemmas
 import Init.Data.Nat.Lemmas
-import Init.Data.Nat.Div.Lemmas
 import Init.Data.Nat.Mod
-import Init.Data.Nat.Div.Lemmas
 import Init.Data.Int.Bitwise.Lemmas
 import Init.Data.Int.Pow
 
@@ -100,12 +98,6 @@ theorem ofFin_eq_ofNat : @BitVec.ofFin w (Fin.mk x lt) = BitVec.ofNat w x := by
 theorem eq_of_toNat_eq {n} : ∀ {x y : BitVec n}, x.toNat = y.toNat → x = y
   | ⟨_, _⟩, ⟨_, _⟩, rfl => rfl
 
-/-- Prove nonequality of bitvectors in terms of nat operations. -/
-theorem toNat_ne_iff_ne {n} {x y : BitVec n} : x.toNat ≠ y.toNat ↔ x ≠ y := by
-  constructor
-  · rintro h rfl; apply h rfl
-  · intro h h_eq; apply h <| eq_of_toNat_eq h_eq
-
 @[simp] theorem val_toFin (x : BitVec w) : x.toFin.val = x.toNat := rfl
 
 @[bv_toNat] theorem toNat_eq {x y : BitVec n} : x = y ↔ x.toNat = y.toNat :=
@@ -450,10 +442,6 @@ theorem toInt_eq_toNat_cond (x : BitVec n) :
         (x.toNat : Int) - (2^n : Nat) :=
   rfl
 
-theorem toInt_eq_toNat_of_lt {x : BitVec n} (h : 2 * x.toNat < 2^n) :
-    x.toInt = x.toNat := by
-  simp [toInt_eq_toNat_cond, h]
-
 theorem msb_eq_false_iff_two_mul_lt {x : BitVec w} : x.msb = false ↔ 2 * x.toNat < 2^w := by
   cases w <;> simp [Nat.pow_succ, Nat.mul_comm _ 2, msb_eq_decide, toNat_of_zero_length]
 
@@ -466,9 +454,6 @@ theorem toInt_eq_msb_cond (x : BitVec w) :
   simp only [BitVec.toInt, ← msb_eq_false_iff_two_mul_lt]
   cases x.msb <;> rfl
 
-theorem toInt_eq_toNat_of_msb {x : BitVec w} (h : x.msb = false) :
-    x.toInt = x.toNat := by
-  simp [toInt_eq_msb_cond, h]
 
 theorem toInt_eq_toNat_bmod (x : BitVec n) : x.toInt = Int.bmod x.toNat (2^n) := by
   simp only [toInt_eq_toNat_cond]
@@ -800,19 +785,6 @@ theorem extractLsb'_eq_extractLsb {w : Nat} (x : BitVec w) (start len : Nat) (h
   unfold allOnes
   simp
 
-@[simp] theorem toInt_allOnes : (allOnes w).toInt = if 0 < w then -1 else 0 := by
-  norm_cast
-  by_cases h : w = 0
-  · subst h
-    simp
-  · have : 1 < 2 ^ w := by simp [h]
-    simp [BitVec.toInt]
-    omega
-
-@[simp] theorem toFin_allOnes : (allOnes w).toFin = Fin.ofNat' (2^w) (2^w - 1) := by
-  ext
-  simp
-
 @[simp] theorem getLsbD_allOnes : (allOnes v).getLsbD i = decide (i < v) := by
   simp [allOnes]
 
@@ -1170,16 +1142,11 @@ theorem getMsb_not {x : BitVec w} :
 /-! ### shiftLeft -/
 
 @[simp, bv_toNat] theorem toNat_shiftLeft {x : BitVec v} :
-    (x <<< n).toNat = x.toNat <<< n % 2^v :=
+    BitVec.toNat (x <<< n) = BitVec.toNat x <<< n % 2^v :=
   BitVec.toNat_ofNat _ _
 
-@[simp] theorem toInt_shiftLeft {x : BitVec w} :
-    (x <<< n).toInt = (x.toNat <<< n : Int).bmod (2^w) := by
-  rw [toInt_eq_toNat_bmod, toNat_shiftLeft, Nat.shiftLeft_eq]
-  simp
-
 @[simp] theorem toFin_shiftLeft {n : Nat} (x : BitVec w) :
-    (x <<< n).toFin = Fin.ofNat' (2^w) (x.toNat <<< n) := rfl
+    BitVec.toFin (x <<< n) = Fin.ofNat' (2^w) (x.toNat <<< n) := rfl
 
 @[simp]
 theorem shiftLeft_zero (x : BitVec w) : x <<< 0 = x := by
@@ -2315,12 +2282,6 @@ theorem ofNat_sub_ofNat {n} (x y : Nat) : BitVec.ofNat n x - BitVec.ofNat n y =
 @[simp, bv_toNat] theorem toNat_neg (x : BitVec n) : (- x).toNat = (2^n - x.toNat) % 2^n := by
   simp [Neg.neg, BitVec.neg]
 
-theorem toNat_neg_of_pos {x : BitVec n} (h : 0#n < x) :
-    (- x).toNat = 2^n - x.toNat := by
-  change 0 < x.toNat at h
-  rw [toNat_neg, Nat.mod_eq_of_lt]
-  omega
-
 theorem toInt_neg {x : BitVec w} :
     (-x).toInt = (-x.toInt).bmod (2 ^ w) := by
   rw [← BitVec.zero_sub, toInt_sub]
@@ -2416,54 +2377,6 @@ theorem not_neg (x : BitVec w) : ~~~(-x) = x + -1#w := by
         show (_ - x.toNat) % _ = _ by rw [Nat.mod_eq_of_lt (by omega)]]
       omega
 
-/-! ### fill -/
-
-@[simp]
-theorem getLsbD_fill {w i : Nat} {v : Bool} :
-    (fill w v).getLsbD i = (v && decide (i < w)) := by
-  by_cases h : v
-  <;> simp [h, BitVec.fill, BitVec.negOne_eq_allOnes]
-
-@[simp]
-theorem getMsbD_fill {w i : Nat} {v : Bool} :
-    (fill w v).getMsbD i = (v && decide (i < w)) := by
-  by_cases h : v
-  <;> simp [h, BitVec.fill, BitVec.negOne_eq_allOnes]
-
-@[simp]
-theorem getElem_fill {w i : Nat} {v : Bool} (h : i < w) :
-    (fill w v)[i] = v := by
-  by_cases h : v
-  <;> simp [h, BitVec.fill, BitVec.negOne_eq_allOnes]
-
-@[simp]
-theorem msb_fill {w : Nat} {v : Bool} :
-    (fill w v).msb = (v && decide (0 < w)) := by
-  simp [BitVec.msb]
-
-theorem fill_eq {w : Nat} {v : Bool} : fill w v = if v = true then allOnes w else 0#w := by
-  by_cases h : v <;> (simp only [h] ; ext ; simp)
-
-@[simp]
-theorem fill_true {w : Nat} : fill w true = allOnes w := by
-  simp [fill_eq]
-
-@[simp]
-theorem fill_false {w : Nat} : fill w false = 0#w := by
-  simp [fill_eq]
-
-@[simp] theorem fill_toNat {w : Nat} {v : Bool} :
-    (fill w v).toNat = if v = true then 2^w - 1 else 0 := by
-  by_cases h : v <;> simp [h]
-
-@[simp] theorem fill_toInt {w : Nat} {v : Bool} :
-    (fill w v).toInt = if v = true && 0 < w then -1 else 0 := by
-  by_cases h : v <;> simp [h]
-
-@[simp] theorem fill_toFin {w : Nat} {v : Bool} :
-    (fill w v).toFin = if v = true then (allOnes w).toFin else Fin.ofNat' (2 ^ w) 0 := by
-  by_cases h : v <;> simp [h]
-
 /-! ### mul -/
 
 theorem mul_def {n} {x y : BitVec n} : x * y = (ofFin <| x.toFin * y.toFin) := by rfl
@@ -2607,13 +2520,13 @@ theorem udiv_def {x y : BitVec n} : x / y = BitVec.ofNat n (x.toNat / y.toNat) :
   rw [← udiv_eq]
   simp [udiv, bv_toNat, h, Nat.mod_eq_of_lt]
 
-@[simp]
-theorem toFin_udiv {x y : BitVec n} : (x / y).toFin = x.toFin / y.toFin := by
-  rfl
-
 @[simp, bv_toNat]
 theorem toNat_udiv {x y : BitVec n} : (x / y).toNat = x.toNat / y.toNat := by
-  rfl
+  rw [udiv_def]
+  by_cases h : y = 0
+  · simp [h]
+  · rw [toNat_ofNat, Nat.mod_eq_of_lt]
+    exact Nat.lt_of_le_of_lt (Nat.div_le_self ..) (by omega)
 
 @[simp]
 theorem zero_udiv {x : BitVec w} : (0#w) / x = 0#w := by
@@ -2649,45 +2562,6 @@ theorem udiv_self {x : BitVec w} :
       ↓reduceIte, toNat_udiv]
     rw [Nat.div_self (by omega), Nat.mod_eq_of_lt (by omega)]
 
-theorem msb_udiv (x y : BitVec w) :
-    (x / y).msb = (x.msb && y == 1#w) := by
-  cases msb_x : x.msb
-  · suffices x.toNat / y.toNat < 2 ^ (w - 1) by simpa [msb_eq_decide]
-    calc
-      x.toNat / y.toNat ≤ x.toNat     := by apply Nat.div_le_self
-                      _ < 2 ^ (w - 1) := by simpa [msb_eq_decide] using msb_x
-  . rcases w with _|w
-    · contradiction
-    · have : (y == 1#_) = decide (y.toNat = 1) := by
-        simp [(· == ·), toNat_eq]
-      simp only [this, Bool.true_and]
-      match hy : y.toNat with
-      | 0 =>
-        obtain rfl : y = 0#_ := eq_of_toNat_eq hy
-        simp
-      | 1 =>
-        obtain rfl : y = 1#_ := eq_of_toNat_eq (by simp [hy])
-        simpa using msb_x
-      | y + 2 =>
-        suffices x.toNat / (y + 2) < 2 ^ w by
-          simp_all [msb_eq_decide, hy]
-        calc
-          x.toNat / (y + 2)
-            ≤ x.toNat / 2 := by apply Nat.div_add_le_right (by omega)
-          _ < 2 ^ w       := by omega
-
-theorem msb_udiv_eq_false_of {x : BitVec w} (h : x.msb = false) (y : BitVec w) :
-    (x / y).msb = false := by
-  simp [msb_udiv, h]
-
-/--
-If `x` is nonnegative (i.e., does not have its msb set),
-then `x / y` is nonnegative, thus `toInt` and `toNat` coincide.
--/
-theorem toInt_udiv_of_msb {x : BitVec w} (h : x.msb = false) (y : BitVec w) :
-    (x / y).toInt = x.toNat / y.toNat := by
-  simp [toInt_eq_msb_cond, msb_udiv_eq_false_of h]
-
 /-! ### umod -/
 
 theorem umod_def {x y : BitVec n} :
@@ -2700,10 +2574,6 @@ theorem umod_def {x y : BitVec n} :
 theorem toNat_umod {x y : BitVec n} :
     (x % y).toNat = x.toNat % y.toNat := rfl
 
-@[simp]
-theorem toFin_umod {x y : BitVec w} :
-    (x % y).toFin = x.toFin % y.toFin := rfl
-
 @[simp]
 theorem umod_zero {x : BitVec n} : x % 0#n = x := by
   simp [umod_def]
@@ -2731,55 +2601,6 @@ theorem umod_eq_and {x y : BitVec 1} : x % y = x &&& (~~~y) := by
     rcases hy with rfl | rfl <;>
       rfl
 
-theorem umod_eq_of_lt {x y : BitVec w} (h : x < y) :
-    x % y = x := by
-  apply eq_of_toNat_eq
-  simp [Nat.mod_eq_of_lt h]
-
-@[simp]
-theorem msb_umod {x y : BitVec w} :
-    (x % y).msb = (x.msb && (x < y || y == 0#w)) := by
-  rw [msb_eq_decide, toNat_umod]
-  cases msb_x : x.msb
-  · suffices x.toNat % y.toNat < 2 ^ (w - 1) by simpa
-    calc
-      x.toNat % y.toNat ≤ x.toNat     := by apply Nat.mod_le
-                      _ < 2 ^ (w - 1) := by simpa [msb_eq_decide] using msb_x
-  . by_cases hy : y = 0
-    · simp_all [msb_eq_decide]
-    · suffices 2 ^ (w - 1) ≤ x.toNat % y.toNat ↔ x < y by simp_all
-      by_cases x_lt_y : x < y
-      . simp_all [Nat.mod_eq_of_lt x_lt_y, msb_eq_decide]
-      · suffices x.toNat % y.toNat < 2 ^ (w - 1) by
-          simpa [x_lt_y]
-        have y_le_x : y.toNat ≤ x.toNat := by
-          simpa using x_lt_y
-        replace hy : y.toNat ≠ 0 :=
-          toNat_ne_iff_ne.mpr hy
-        by_cases msb_y : y.toNat < 2 ^ (w - 1)
-        · have : x.toNat % y.toNat < y.toNat := Nat.mod_lt _ (by omega)
-          omega
-        · rcases w with _|w
-          · contradiction
-          simp only [Nat.add_one_sub_one]
-          replace msb_y : 2 ^ w ≤ y.toNat := by
-            simpa using msb_y
-          have : y.toNat ≤ y.toNat * (x.toNat / y.toNat) := by
-              apply Nat.le_mul_of_pos_right
-              apply Nat.div_pos y_le_x
-              omega
-          have : x.toNat % y.toNat ≤ x.toNat - y.toNat := by
-            rw [Nat.mod_eq_sub]; omega
-          omega
-
-theorem toInt_umod {x y : BitVec w} :
-    (x % y).toInt = (x.toNat % y.toNat : Int).bmod (2 ^ w) := by
-  simp [toInt_eq_toNat_bmod]
-
-theorem toInt_umod_of_msb {x y : BitVec w} (h : x.msb = false) :
-    (x % y).toInt = x.toInt % y.toNat := by
-  simp [toInt_eq_msb_cond, h]
-
 /-! ### smtUDiv -/
 
 theorem smtUDiv_eq (x y : BitVec w) : smtUDiv x y = if y = 0#w then allOnes w else x / y := by
@@ -2936,12 +2757,7 @@ theorem smod_zero {x : BitVec n} : x.smod 0#n = x := by
 
 /-! # Rotate Left -/
 
-/--`rotateLeft` is defined in terms of left and right shifts. -/
-theorem rotateLeft_def {x : BitVec w} {r : Nat} :
-    x.rotateLeft r = (x <<< (r % w)) ||| (x >>> (w - r % w)) := by
-  simp only [rotateLeft, rotateLeftAux]
-
-/-- `rotateLeft` is invariant under `mod` by the bitwidth. -/
+/-- rotateLeft is invariant under `mod` by the bitwidth. -/
 @[simp]
 theorem rotateLeft_mod_eq_rotateLeft {x : BitVec w} {r : Nat} :
     x.rotateLeft (r % w) = x.rotateLeft r := by
@@ -3085,18 +2901,8 @@ theorem msb_rotateLeft {m w : Nat} {x : BitVec w} :
   · simp
     omega
 
-@[simp]
-theorem toNat_rotateLeft {x : BitVec w} {r : Nat} :
-    (x.rotateLeft r).toNat = (x.toNat <<< (r % w)) % (2^w) ||| x.toNat >>> (w - r % w) := by
-  simp only [rotateLeft_def, toNat_shiftLeft, toNat_ushiftRight, toNat_or]
-
 /-! ## Rotate Right -/
 
-/-- `rotateRight` is defined in terms of left and right shifts. -/
-theorem rotateRight_def {x : BitVec w} {r : Nat} :
-    x.rotateRight r = (x >>> (r % w)) ||| (x <<< (w - r % w)) := by
-  simp only [rotateRight, rotateRightAux]
-
 /--
 Accessing bits in `x.rotateRight r` the range `[0, w-r)` is equal to
 accessing bits `x` in the range `[r, w)`.
@@ -3232,11 +3038,6 @@ theorem msb_rotateRight {r w : Nat} {x : BitVec w} :
     simp [h₁]
   · simp [show w = 0 by omega]
 
-@[simp]
-theorem toNat_rotateRight {x : BitVec w} {r : Nat} :
-    (x.rotateRight r).toNat = (x.toNat >>> (r % w)) ||| x.toNat <<< (w - r % w) % (2^w) := by
-  simp only [rotateRight_def, toNat_shiftLeft, toNat_ushiftRight, toNat_or]
-
 /- ## twoPow -/
 
 theorem twoPow_eq (w : Nat) (i : Nat) : twoPow w i = 1#w <<< i := by

src/Init/Data/Int/DivModLemmas.lean

@@ -534,13 +534,6 @@ theorem mul_emod (a b n : Int) : (a * b) % n = (a % n) * (b % n) % n := by
 @[simp] theorem emod_emod (a b : Int) : (a % b) % b = a % b := by
   conv => rhs; rw [← emod_add_ediv a b, add_mul_emod_self_left]
 
-@[simp] theorem emod_sub_emod (m n k : Int) : (m % n - k) % n = (m - k) % n :=
-  Int.emod_add_emod m n (-k)
-
-@[simp] theorem sub_emod_emod (m n k : Int) : (m - n % k) % k = (m - n) % k := by
-  apply (emod_add_cancel_right (n % k)).mp
-  rw [Int.sub_add_cancel, Int.add_emod_emod, Int.sub_add_cancel]
-
 theorem sub_emod (a b n : Int) : (a - b) % n = (a % n - b % n) % n := by
   apply (emod_add_cancel_right b).mp
   rw [Int.sub_add_cancel, ← Int.add_emod_emod, Int.sub_add_cancel, emod_emod]
@@ -1105,32 +1098,6 @@ theorem bmod_def (x : Int) (m : Nat) : bmod x m =
     (x % m) - m :=
   rfl
 
-theorem bdiv_add_bmod (x : Int) (m : Nat) : m * bdiv x m + bmod x m = x := by
-  unfold bdiv bmod
-  split
-  · simp_all only [Nat.cast_ofNat_Int, Int.mul_zero, emod_zero, Int.zero_add, Int.sub_zero,
-      ite_self]
-  · dsimp only
-    split
-    · exact ediv_add_emod x m
-    · rw [Int.mul_add, Int.mul_one, Int.add_assoc, Int.add_comm m, Int.sub_add_cancel]
-      exact ediv_add_emod x m
-
-theorem bmod_add_bdiv (x : Int) (m : Nat) : bmod x m + m * bdiv x m = x := by
-  rw [Int.add_comm]; exact bdiv_add_bmod x m
-
-theorem bdiv_add_bmod' (x : Int) (m : Nat) : bdiv x m * m + bmod x m = x := by
-  rw [Int.mul_comm]; exact bdiv_add_bmod x m
-
-theorem bmod_add_bdiv' (x : Int) (m : Nat) : bmod x m + bdiv x m * m = x := by
-  rw [Int.add_comm]; exact bdiv_add_bmod' x m
-
-theorem bmod_eq_self_sub_mul_bdiv (x : Int) (m : Nat) : bmod x m = x - m * bdiv x m := by
-  rw [← Int.add_sub_cancel (bmod x m), bmod_add_bdiv]
-
-theorem bmod_eq_self_sub_bdiv_mul (x : Int) (m : Nat) : bmod x m = x - bdiv x m * m := by
-  rw [← Int.add_sub_cancel (bmod x m), bmod_add_bdiv']
-
 theorem bmod_pos (x : Int) (m : Nat) (p : x % m < (m + 1) / 2) : bmod x m = x % m := by
   simp [bmod_def, p]
 

src/Init/Data/List/Lemmas.lean

@@ -1,8 +1,7 @@
 /-
 Copyright (c) 2014 Parikshit Khanna. All rights reserved.
 Released under Apache 2.0 license as described in the file LICENSE.
-Authors: Parikshit Khanna, Jeremy Avigad, Leonardo de Moura, Floris van Doorn, Mario Carneiro,
-  Kim Morrison
+Authors: Parikshit Khanna, Jeremy Avigad, Leonardo de Moura, Floris van Doorn, Mario Carneiro
 -/
 prelude
 import Init.Data.Bool
@@ -758,6 +757,207 @@ theorem length_eq_of_beq [BEq α] {l₁ l₂ : List α} (h : l₁ == l₂) : l
     | nil => simp
     | cons b l₂ => simp [isEqv, ih]
 
+/-! ### foldlM and foldrM -/
+
+@[simp] theorem foldlM_reverse [Monad m] (l : List α) (f : β → α → m β) (b) :
+    l.reverse.foldlM f b = l.foldrM (fun x y => f y x) b := rfl
+
+@[simp] theorem foldlM_append [Monad m] [LawfulMonad m] (f : β → α → m β) (b) (l l' : List α) :
+    (l ++ l').foldlM f b = l.foldlM f b >>= l'.foldlM f := by
+  induction l generalizing b <;> simp [*]
+
+@[simp] theorem foldrM_cons [Monad m] [LawfulMonad m] (a : α) (l) (f : α → β → m β) (b) :
+    (a :: l).foldrM f b = l.foldrM f b >>= f a := by
+  simp only [foldrM]
+  induction l <;> simp_all
+
+theorem foldl_eq_foldlM (f : β → α → β) (b) (l : List α) :
+    l.foldl f b = l.foldlM (m := Id) f b := by
+  induction l generalizing b <;> simp [*, foldl]
+
+theorem foldr_eq_foldrM (f : α → β → β) (b) (l : List α) :
+    l.foldr f b = l.foldrM (m := Id) f b := by
+  induction l <;> simp [*, foldr]
+
+@[simp] theorem id_run_foldlM (f : β → α → Id β) (b) (l : List α) :
+    Id.run (l.foldlM f b) = l.foldl f b := (foldl_eq_foldlM f b l).symm
+
+@[simp] theorem id_run_foldrM (f : α → β → Id β) (b) (l : List α) :
+    Id.run (l.foldrM f b) = l.foldr f b := (foldr_eq_foldrM f b l).symm
+
+/-! ### foldl and foldr -/
+
+@[simp] theorem foldr_cons_eq_append (l : List α) : l.foldr cons l' = l ++ l' := by
+  induction l <;> simp [*]
+
+@[deprecated foldr_cons_eq_append (since := "2024-08-22")] abbrev foldr_self_append := @foldr_cons_eq_append
+
+@[simp] theorem foldl_flip_cons_eq_append (l : List α) : l.foldl (fun x y => y :: x) l' = l.reverse ++ l' := by
+  induction l generalizing l' <;> simp [*]
+
+theorem foldr_cons_nil (l : List α) : l.foldr cons [] = l := by simp
+
+@[deprecated foldr_cons_nil (since := "2024-09-04")] abbrev foldr_self := @foldr_cons_nil
+
+theorem foldl_map (f : β₁ → β₂) (g : α → β₂ → α) (l : List β₁) (init : α) :
+    (l.map f).foldl g init = l.foldl (fun x y => g x (f y)) init := by
+  induction l generalizing init <;> simp [*]
+
+theorem foldr_map (f : α₁ → α₂) (g : α₂ → β → β) (l : List α₁) (init : β) :
+    (l.map f).foldr g init = l.foldr (fun x y => g (f x) y) init := by
+  induction l generalizing init <;> simp [*]
+
+theorem foldl_filterMap (f : α → Option β) (g : γ → β → γ) (l : List α) (init : γ) :
+    (l.filterMap f).foldl g init = l.foldl (fun x y => match f y with | some b => g x b | none => x) init := by
+  induction l generalizing init with
+  | nil => rfl
+  | cons a l ih =>
+    simp only [filterMap_cons, foldl_cons]
+    cases f a <;> simp [ih]
+
+theorem foldr_filterMap (f : α → Option β) (g : β → γ → γ) (l : List α) (init : γ) :
+    (l.filterMap f).foldr g init = l.foldr (fun x y => match f x with | some b => g b y | none => y) init := by
+  induction l generalizing init with
+  | nil => rfl
+  | cons a l ih =>
+    simp only [filterMap_cons, foldr_cons]
+    cases f a <;> simp [ih]
+
+theorem foldl_map' (g : α → β) (f : α → α → α) (f' : β → β → β) (a : α) (l : List α)
+    (h : ∀ x y, f' (g x) (g y) = g (f x y)) :
+    (l.map g).foldl f' (g a) = g (l.foldl f a) := by
+  induction l generalizing a
+  · simp
+  · simp [*, h]
+
+theorem foldr_map' (g : α → β) (f : α → α → α) (f' : β → β → β) (a : α) (l : List α)
+    (h : ∀ x y, f' (g x) (g y) = g (f x y)) :
+    (l.map g).foldr f' (g a) = g (l.foldr f a) := by
+  induction l generalizing a
+  · simp
+  · simp [*, h]
+
+theorem foldl_assoc {op : α → α → α} [ha : Std.Associative op] :
+    ∀ {l : List α} {a₁ a₂}, l.foldl op (op a₁ a₂) = op a₁ (l.foldl op a₂)
+  | [], a₁, a₂ => rfl
+  | a :: l, a₁, a₂ => by
+    simp only [foldl_cons, ha.assoc]
+    rw [foldl_assoc]
+
+theorem foldr_assoc {op : α → α → α} [ha : Std.Associative op] :
+    ∀ {l : List α} {a₁ a₂}, l.foldr op (op a₁ a₂) = op (l.foldr op a₁) a₂
+  | [], a₁, a₂ => rfl
+  | a :: l, a₁, a₂ => by
+    simp only [foldr_cons, ha.assoc]
+    rw [foldr_assoc]
+
+theorem foldl_hom (f : α₁ → α₂) (g₁ : α₁ → β → α₁) (g₂ : α₂ → β → α₂) (l : List β) (init : α₁)
+    (H : ∀ x y, g₂ (f x) y = f (g₁ x y)) : l.foldl g₂ (f init) = f (l.foldl g₁ init) := by
+  induction l generalizing init <;> simp [*, H]
+
+theorem foldr_hom (f : β₁ → β₂) (g₁ : α → β₁ → β₁) (g₂ : α → β₂ → β₂) (l : List α) (init : β₁)
+    (H : ∀ x y, g₂ x (f y) = f (g₁ x y)) : l.foldr g₂ (f init) = f (l.foldr g₁ init) := by
+  induction l <;> simp [*, H]
+
+/--
+Prove a proposition about the result of `List.foldl`,
+by proving it for the initial data,
+and the implication that the operation applied to any element of the list preserves the property.
+
+The motive can take values in `Sort _`, so this may be used to construct data,
+as well as to prove propositions.
+-/
+def foldlRecOn {motive : β → Sort _} : ∀ (l : List α) (op : β → α → β) (b : β) (_ : motive b)
+    (_ : ∀ (b : β) (_ : motive b) (a : α) (_ : a ∈ l), motive (op b a)), motive (List.foldl op b l)
+  | [], _, _, hb, _ => hb
+  | hd :: tl, op, b, hb, hl =>
+    foldlRecOn tl op (op b hd) (hl b hb hd (mem_cons_self hd tl))
+      fun y hy x hx => hl y hy x (mem_cons_of_mem hd hx)
+
+@[simp] theorem foldlRecOn_nil {motive : β → Sort _} (hb : motive b)
+    (hl : ∀ (b : β) (_ : motive b) (a : α) (_ : a ∈ []), motive (op b a)) :
+    foldlRecOn [] op b hb hl = hb := rfl
+
+@[simp] theorem foldlRecOn_cons {motive : β → Sort _} (hb : motive b)
+    (hl : ∀ (b : β) (_ : motive b) (a : α) (_ : a ∈ x :: l), motive (op b a)) :
+    foldlRecOn (x :: l) op b hb hl =
+      foldlRecOn l op (op b x) (hl b hb x (mem_cons_self x l))
+        (fun b c a m => hl b c a (mem_cons_of_mem x m)) :=
+  rfl
+
+/--
+Prove a proposition about the result of `List.foldr`,
+by proving it for the initial data,
+and the implication that the operation applied to any element of the list preserves the property.
+
+The motive can take values in `Sort _`, so this may be used to construct data,
+as well as to prove propositions.
+-/
+def foldrRecOn {motive : β → Sort _} : ∀ (l : List α) (op : α → β → β) (b : β) (_ : motive b)
+    (_ : ∀ (b : β) (_ : motive b) (a : α) (_ : a ∈ l), motive (op a b)), motive (List.foldr op b l)
+  | nil, _, _, hb, _ => hb
+  | x :: l, op, b, hb, hl =>
+    hl (foldr op b l)
+      (foldrRecOn l op b hb fun b c a m => hl b c a (mem_cons_of_mem x m)) x (mem_cons_self x l)
+
+@[simp] theorem foldrRecOn_nil {motive : β → Sort _} (hb : motive b)
+    (hl : ∀ (b : β) (_ : motive b) (a : α) (_ : a ∈ []), motive (op a b)) :
+    foldrRecOn [] op b hb hl = hb := rfl
+
+@[simp] theorem foldrRecOn_cons {motive : β → Sort _} (hb : motive b)
+    (hl : ∀ (b : β) (_ : motive b) (a : α) (_ : a ∈ x :: l), motive (op a b)) :
+    foldrRecOn (x :: l) op b hb hl =
+      hl _ (foldrRecOn l op b hb fun b c a m => hl b c a (mem_cons_of_mem x m))
+        x (mem_cons_self x l) :=
+  rfl
+
+/--
+We can prove that two folds over the same list are related (by some arbitrary relation)
+if we know that the initial elements are related and the folding function, for each element of the list,
+preserves the relation.
+-/
+theorem foldl_rel {l : List α} {f g : β → α → β} {a b : β} (r : β → β → Prop)
+    (h : r a b) (h' : ∀ (a : α), a ∈ l → ∀ (c c' : β), r c c' → r (f c a) (g c' a)) :
+    r (l.foldl (fun acc a => f acc a) a) (l.foldl (fun acc a => g acc a) b) := by
+  induction l generalizing a b with
+  | nil => simp_all
+  | cons a l ih =>
+    simp only [foldl_cons]
+    apply ih
+    · simp_all
+    · exact fun a m c c' h => h' _ (by simp_all) _ _ h
+
+/--
+We can prove that two folds over the same list are related (by some arbitrary relation)
+if we know that the initial elements are related and the folding function, for each element of the list,
+preserves the relation.
+-/
+theorem foldr_rel {l : List α} {f g : α → β → β} {a b : β} (r : β → β → Prop)
+    (h : r a b) (h' : ∀ (a : α), a ∈ l → ∀ (c c' : β), r c c' → r (f a c) (g a c')) :
+    r (l.foldr (fun a acc => f a acc) a) (l.foldr (fun a acc => g a acc) b) := by
+  induction l generalizing a b with
+  | nil => simp_all
+  | cons a l ih =>
+    simp only [foldr_cons]
+    apply h'
+    · simp
+    · exact ih h fun a m c c' h => h' _ (by simp_all) _ _ h
+
+@[simp] theorem foldl_add_const (l : List α) (a b : Nat) :
+    l.foldl (fun x _ => x + a) b = b + a * l.length := by
+  induction l generalizing b with
+  | nil => simp
+  | cons y l ih =>
+    simp only [foldl_cons, ih, length_cons, Nat.mul_add, Nat.mul_one, Nat.add_assoc,
+      Nat.add_comm a]
+
+@[simp] theorem foldr_add_const (l : List α) (a b : Nat) :
+    l.foldr (fun _ x => x + a) b = b + a * l.length := by
+  induction l generalizing b with
+  | nil => simp
+  | cons y l ih =>
+    simp only [foldr_cons, ih, length_cons, Nat.mul_add, Nat.mul_one, Nat.add_assoc]
+
 /-! ### getLast -/
 
 theorem getLast_eq_getElem : ∀ (l : List α) (h : l ≠ []),
@@ -1016,6 +1216,27 @@ theorem getLast?_tail (l : List α) : (tail l).getLast? = if l.length = 1 then n
 
 /-! ### map -/
 
+@[simp] theorem map_id_fun : map (id : α → α) = id := by
+  funext l
+  induction l <;> simp_all
+
+/-- `map_id_fun'` differs from `map_id_fun` by representing the identity function as a lambda, rather than `id`. -/
+@[simp] theorem map_id_fun' : map (fun (a : α) => a) = id := map_id_fun
+
+-- This is not a `@[simp]` lemma because `map_id_fun` will apply.
+theorem map_id (l : List α) : map (id : α → α) l = l := by
+  induction l <;> simp_all
+
+/-- `map_id'` differs from `map_id` by representing the identity function as a lambda, rather than `id`. -/
+-- This is not a `@[simp]` lemma because `map_id_fun'` will apply.
+theorem map_id' (l : List α) : map (fun (a : α) => a) l = l := map_id l
+
+/-- Variant of `map_id`, with a side condition that the function is pointwise the identity. -/
+theorem map_id'' {f : α → α} (h : ∀ x, f x = x) (l : List α) : map f l = l := by
+  simp [show f = id from funext h]
+
+theorem map_singleton (f : α → β) (a : α) : map f [a] = [f a] := rfl
+
 @[simp] theorem length_map (as : List α) (f : α → β) : (as.map f).length = as.length := by
   induction as with
   | nil => simp [List.map]
@@ -1041,27 +1262,6 @@ theorem get_map (f : α → β) {l i} :
     get (map f l) i = f (get l ⟨i, length_map l f ▸ i.2⟩) := by
   simp
 
-@[simp] theorem map_id_fun : map (id : α → α) = id := by
-  funext l
-  induction l <;> simp_all
-
-/-- `map_id_fun'` differs from `map_id_fun` by representing the identity function as a lambda, rather than `id`. -/
-@[simp] theorem map_id_fun' : map (fun (a : α) => a) = id := map_id_fun
-
--- This is not a `@[simp]` lemma because `map_id_fun` will apply.
-theorem map_id (l : List α) : map (id : α → α) l = l := by
-  induction l <;> simp_all
-
-/-- `map_id'` differs from `map_id` by representing the identity function as a lambda, rather than `id`. -/
--- This is not a `@[simp]` lemma because `map_id_fun'` will apply.
-theorem map_id' (l : List α) : map (fun (a : α) => a) l = l := map_id l
-
-/-- Variant of `map_id`, with a side condition that the function is pointwise the identity. -/
-theorem map_id'' {f : α → α} (h : ∀ x, f x = x) (l : List α) : map f l = l := by
-  simp [show f = id from funext h]
-
-theorem map_singleton (f : α → β) (a : α) : map f [a] = [f a] := rfl
-
 @[simp] theorem mem_map {f : α → β} : ∀ {l : List α}, b ∈ l.map f ↔ ∃ a, a ∈ l ∧ f a = b
   | [] => by simp
   | _ :: l => by simp [mem_map (l := l), eq_comm (a := b)]
@@ -1115,10 +1315,6 @@ theorem map_eq_cons_iff' {f : α → β} {l : List α} :
 
 @[deprecated map_eq_cons' (since := "2024-09-05")] abbrev map_eq_cons' := @map_eq_cons_iff'
 
-@[simp] theorem map_eq_singleton_iff {f : α → β} {l : List α} {b : β} :
-    map f l = [b] ↔ ∃ a, l = [a] ∧ f a = b := by
-  simp [map_eq_cons_iff]
-
 theorem map_eq_map_iff : map f l = map g l ↔ ∀ a ∈ l, f a = g a := by
   induction l <;> simp
 
@@ -1285,7 +1481,7 @@ theorem map_filter_eq_foldr (f : α → β) (p : α → Bool) (as : List α) :
 @[simp] theorem filter_append {p : α → Bool} :
     ∀ (l₁ l₂ : List α), filter p (l₁ ++ l₂) = filter p l₁ ++ filter p l₂
   | [], _ => rfl
-  | a :: l₁, l₂ => by simp only [cons_append, filter]; split <;> simp [filter_append l₁]
+  | a :: l₁, l₂ => by simp [filter]; split <;> simp [filter_append l₁]
 
 theorem filter_eq_cons_iff {l} {a} {as} :
     filter p l = a :: as ↔
@@ -1494,34 +1690,6 @@ theorem filterMap_eq_cons_iff {l} {b} {bs} :
 @[simp] theorem cons_append_fun (a : α) (as : List α) :
     (fun bs => ((a :: as) ++ bs)) = fun bs => a :: (as ++ bs) := rfl
 
-@[simp] theorem mem_append {a : α} {s t : List α} : a ∈ s ++ t ↔ a ∈ s ∨ a ∈ t := by
-  induction s <;> simp_all [or_assoc]
-
-theorem not_mem_append {a : α} {s t : List α} (h₁ : a ∉ s) (h₂ : a ∉ t) : a ∉ s ++ t :=
-  mt mem_append.1 $ not_or.mpr ⟨h₁, h₂⟩
-
-@[deprecated mem_append (since := "2025-01-13")]
-theorem mem_append_eq (a : α) (s t : List α) : (a ∈ s ++ t) = (a ∈ s ∨ a ∈ t) :=
-  propext mem_append
-
-@[deprecated mem_append_left (since := "2024-11-20")] abbrev mem_append_of_mem_left := @mem_append_left
-@[deprecated mem_append_right (since := "2024-11-20")] abbrev mem_append_of_mem_right := @mem_append_right
-
-/--
-See also `eq_append_cons_of_mem`, which proves a stronger version
-in which the initial list must not contain the element.
--/
-theorem append_of_mem {a : α} {l : List α} : a ∈ l → ∃ s t : List α, l = s ++ a :: t
-  | .head l => ⟨[], l, rfl⟩
-  | .tail b h => let ⟨s, t, h'⟩ := append_of_mem h; ⟨b::s, t, by rw [h', cons_append]⟩
-
-theorem mem_iff_append {a : α} {l : List α} : a ∈ l ↔ ∃ s t : List α, l = s ++ a :: t :=
-  ⟨append_of_mem, fun ⟨s, t, e⟩ => e ▸ by simp⟩
-
-theorem forall_mem_append {p : α → Prop} {l₁ l₂ : List α} :
-    (∀ (x) (_ : x ∈ l₁ ++ l₂), p x) ↔ (∀ (x) (_ : x ∈ l₁), p x) ∧ (∀ (x) (_ : x ∈ l₂), p x) := by
-  simp only [mem_append, or_imp, forall_and]
-
 theorem getElem_append {l₁ l₂ : List α} (i : Nat) (h : i < (l₁ ++ l₂).length) :
     (l₁ ++ l₂)[i] = if h' : i < l₁.length then l₁[i] else l₂[i - l₁.length]'(by simp at h h'; exact Nat.sub_lt_left_of_lt_add h' h) := by
   split <;> rename_i h'
@@ -1589,6 +1757,14 @@ theorem get_of_append {l : List α} (eq : l = l₁ ++ a :: l₂) (h : l₁.lengt
     l.get ⟨i, get_of_append_proof eq h⟩ = a := Option.some.inj <| by
   rw [← get?_eq_get, eq, get?_append_right (h ▸ Nat.le_refl _), h, Nat.sub_self]; rfl
 
+/--
+See also `eq_append_cons_of_mem`, which proves a stronger version
+in which the initial list must not contain the element.
+-/
+theorem append_of_mem {a : α} {l : List α} : a ∈ l → ∃ s t : List α, l = s ++ a :: t
+  | .head l => ⟨[], l, rfl⟩
+  | .tail b h => let ⟨s, t, h'⟩ := append_of_mem h; ⟨b::s, t, by rw [h', cons_append]⟩
+
 @[simp 1100] theorem singleton_append : [x] ++ l = x :: l := rfl
 
 theorem append_inj :
@@ -1605,8 +1781,8 @@ theorem append_inj_left (h : s₁ ++ t₁ = s₂ ++ t₂) (hl : length s₁ = le
 
 /-- Variant of `append_inj` instead requiring equality of the lengths of the second lists. -/
 theorem append_inj' (h : s₁ ++ t₁ = s₂ ++ t₂) (hl : length t₁ = length t₂) : s₁ = s₂ ∧ t₁ = t₂ :=
-  append_inj h <| @Nat.add_right_cancel _ t₁.length _ <| by
-    let hap := congrArg length h; simp only [length_append, ← hl] at hap; exact hap
+  append_inj h <| @Nat.add_right_cancel _ (length t₁) _ <| by
+  let hap := congrArg length h; simp only [length_append, ← hl] at hap; exact hap
 
 /-- Variant of `append_inj_right` instead requiring equality of the lengths of the second lists. -/
 theorem append_inj_right' (h : s₁ ++ t₁ = s₂ ++ t₂) (hl : length t₁ = length t₂) : t₁ = t₂ :=
@@ -1634,6 +1810,9 @@ theorem append_left_inj {s₁ s₂ : List α} (t) : s₁ ++ t = s₂ ++ t ↔ s
 @[simp] theorem self_eq_append_right {x y : List α} : x = x ++ y ↔ y = [] := by
   rw [eq_comm, append_right_eq_self]
 
+@[simp] theorem append_eq_nil : p ++ q = [] ↔ p = [] ∧ q = [] := by
+  cases p <;> simp
+
 theorem getLast_concat {a : α} : ∀ (l : List α), getLast (l ++ [a]) (by simp) = a
   | [] => rfl
   | a::t => by
@@ -1659,54 +1838,6 @@ theorem get?_append {l₁ l₂ : List α} {n : Nat} (hn : n < l₁.length) :
     (l₁ ++ l₂).get? n = l₁.get? n := by
   simp [getElem?_append_left hn]
 
-@[simp] theorem append_eq_nil_iff : p ++ q = [] ↔ p = [] ∧ q = [] := by
-  cases p <;> simp
-
-@[deprecated append_eq_nil_iff (since := "2025-01-13")] abbrev append_eq_nil := @append_eq_nil_iff
-
-@[simp] theorem nil_eq_append_iff : [] = a ++ b ↔ a = [] ∧ b = [] := by
-  rw [eq_comm, append_eq_nil_iff]
-
-@[deprecated nil_eq_append_iff (since := "2024-07-24")] abbrev nil_eq_append := @nil_eq_append_iff
-
-theorem append_ne_nil_of_left_ne_nil {s : List α} (h : s ≠ []) (t : List α) : s ++ t ≠ [] := by simp_all
-theorem append_ne_nil_of_right_ne_nil (s : List α) : t ≠ [] → s ++ t ≠ [] := by simp_all
-
-@[deprecated append_ne_nil_of_left_ne_nil (since := "2024-07-24")]
-theorem append_ne_nil_of_ne_nil_left {s : List α} (h : s ≠ []) (t : List α) : s ++ t ≠ [] := by simp_all
-@[deprecated append_ne_nil_of_right_ne_nil (since := "2024-07-24")]
-theorem append_ne_nil_of_ne_nil_right (s : List α) : t ≠ [] → s ++ t ≠ [] := by simp_all
-
-theorem append_eq_cons_iff :
-    a ++ b = x :: c ↔ (a = [] ∧ b = x :: c) ∨ (∃ a', a = x :: a' ∧ c = a' ++ b) := by
-  cases a with simp | cons a as => ?_
-  exact ⟨fun h => ⟨as, by simp [h]⟩, fun ⟨a', ⟨aeq, aseq⟩, h⟩ => ⟨aeq, by rw [aseq, h]⟩⟩
-
-@[deprecated append_eq_cons_iff (since := "2024-07-24")] abbrev append_eq_cons := @append_eq_cons_iff
-
-theorem cons_eq_append_iff :
-    x :: c = a ++ b ↔ (a = [] ∧ b = x :: c) ∨ (∃ a', a = x :: a' ∧ c = a' ++ b) := by
-  rw [eq_comm, append_eq_cons_iff]
-
-@[deprecated cons_eq_append_iff (since := "2024-07-24")] abbrev cons_eq_append := @cons_eq_append_iff
-
-theorem append_eq_singleton_iff :
-    a ++ b = [x] ↔ (a = [] ∧ b = [x]) ∨ (a = [x] ∧ b = []) := by
-  cases a <;> cases b <;> simp
-
-theorem singleton_eq_append_iff :
-    [x] = a ++ b ↔ (a = [] ∧ b = [x]) ∨ (a = [x] ∧ b = []) := by
-  cases a <;> cases b <;> simp [eq_comm]
-
-theorem append_eq_append_iff {a b c d : List α} :
-    a ++ b = c ++ d ↔ (∃ a', c = a ++ a' ∧ b = a' ++ d) ∨ ∃ c', a = c ++ c' ∧ d = c' ++ b := by
-  induction a generalizing c with
-  | nil => simp_all
-  | cons a as ih => cases c <;> simp [eq_comm, and_assoc, ih, and_or_left]
-
-@[deprecated append_inj (since := "2024-07-24")] abbrev append_inj_of_length_left := @append_inj
-@[deprecated append_inj' (since := "2024-07-24")] abbrev append_inj_of_length_right := @append_inj'
-
 @[simp] theorem head_append_of_ne_nil {l : List α} {w₁} (w₂) :
     head (l ++ l') w₁ = head l w₂ := by
   match l, w₂ with
@@ -1756,6 +1887,60 @@ theorem tail_append {l l' : List α} : (l ++ l').tail = if l.isEmpty then l'.tai
 
 @[deprecated tail_append_of_ne_nil (since := "2024-07-24")] abbrev tail_append_left := @tail_append_of_ne_nil
 
+theorem nil_eq_append_iff : [] = a ++ b ↔ a = [] ∧ b = [] := by
+  rw [eq_comm, append_eq_nil]
+
+@[deprecated nil_eq_append_iff (since := "2024-07-24")] abbrev nil_eq_append := @nil_eq_append_iff
+
+theorem append_ne_nil_of_left_ne_nil {s : List α} (h : s ≠ []) (t : List α) : s ++ t ≠ [] := by simp_all
+theorem append_ne_nil_of_right_ne_nil (s : List α) : t ≠ [] → s ++ t ≠ [] := by simp_all
+
+@[deprecated append_ne_nil_of_left_ne_nil (since := "2024-07-24")]
+theorem append_ne_nil_of_ne_nil_left {s : List α} (h : s ≠ []) (t : List α) : s ++ t ≠ [] := by simp_all
+@[deprecated append_ne_nil_of_right_ne_nil (since := "2024-07-24")]
+theorem append_ne_nil_of_ne_nil_right (s : List α) : t ≠ [] → s ++ t ≠ [] := by simp_all
+
+theorem append_eq_cons_iff :
+    a ++ b = x :: c ↔ (a = [] ∧ b = x :: c) ∨ (∃ a', a = x :: a' ∧ c = a' ++ b) := by
+  cases a with simp | cons a as => ?_
+  exact ⟨fun h => ⟨as, by simp [h]⟩, fun ⟨a', ⟨aeq, aseq⟩, h⟩ => ⟨aeq, by rw [aseq, h]⟩⟩
+
+@[deprecated append_eq_cons_iff (since := "2024-07-24")] abbrev append_eq_cons := @append_eq_cons_iff
+
+theorem cons_eq_append_iff :
+    x :: c = a ++ b ↔ (a = [] ∧ b = x :: c) ∨ (∃ a', a = x :: a' ∧ c = a' ++ b) := by
+  rw [eq_comm, append_eq_cons_iff]
+
+@[deprecated cons_eq_append_iff (since := "2024-07-24")] abbrev cons_eq_append := @cons_eq_append_iff
+
+theorem append_eq_append_iff {a b c d : List α} :
+    a ++ b = c ++ d ↔ (∃ a', c = a ++ a' ∧ b = a' ++ d) ∨ ∃ c', a = c ++ c' ∧ d = c' ++ b := by
+  induction a generalizing c with
+  | nil => simp_all
+  | cons a as ih => cases c <;> simp [eq_comm, and_assoc, ih, and_or_left]
+
+@[deprecated append_inj (since := "2024-07-24")] abbrev append_inj_of_length_left := @append_inj
+@[deprecated append_inj' (since := "2024-07-24")] abbrev append_inj_of_length_right := @append_inj'
+
+@[simp] theorem mem_append {a : α} {s t : List α} : a ∈ s ++ t ↔ a ∈ s ∨ a ∈ t := by
+  induction s <;> simp_all [or_assoc]
+
+theorem not_mem_append {a : α} {s t : List α} (h₁ : a ∉ s) (h₂ : a ∉ t) : a ∉ s ++ t :=
+  mt mem_append.1 $ not_or.mpr ⟨h₁, h₂⟩
+
+theorem mem_append_eq (a : α) (s t : List α) : (a ∈ s ++ t) = (a ∈ s ∨ a ∈ t) :=
+  propext mem_append
+
+@[deprecated mem_append_left (since := "2024-11-20")] abbrev mem_append_of_mem_left := @mem_append_left
+@[deprecated mem_append_right (since := "2024-11-20")] abbrev mem_append_of_mem_right := @mem_append_right
+
+theorem mem_iff_append {a : α} {l : List α} : a ∈ l ↔ ∃ s t : List α, l = s ++ a :: t :=
+  ⟨append_of_mem, fun ⟨s, t, e⟩ => e ▸ by simp⟩
+
+theorem forall_mem_append {p : α → Prop} {l₁ l₂ : List α} :
+    (∀ (x) (_ : x ∈ l₁ ++ l₂), p x) ↔ (∀ (x) (_ : x ∈ l₁), p x) ∧ (∀ (x) (_ : x ∈ l₂), p x) := by
+  simp only [mem_append, or_imp, forall_and]
+
 theorem set_append {s t : List α} :
     (s ++ t).set i x = if i < s.length then s.set i x ++ t else s ++ t.set (i - s.length) x := by
   induction s generalizing i with
@@ -1776,6 +1961,16 @@ theorem set_append {s t : List α} :
     (s ++ t).set i x = s ++ t.set (i - s.length) x := by
   rw [set_append, if_neg (by simp_all)]
 
+@[simp] theorem foldrM_append [Monad m] [LawfulMonad m] (f : α → β → m β) (b) (l l' : List α) :
+    (l ++ l').foldrM f b = l'.foldrM f b >>= l.foldrM f := by
+  induction l <;> simp [*]
+
+@[simp] theorem foldl_append {β : Type _} (f : β → α → β) (b) (l l' : List α) :
+    (l ++ l').foldl f b = l'.foldl f (l.foldl f b) := by simp [foldl_eq_foldlM]
+
+@[simp] theorem foldr_append (f : α → β → β) (b) (l l' : List α) :
+    (l ++ l').foldr f b = l.foldr f (l'.foldr f b) := by simp [foldr_eq_foldrM]
+
 theorem filterMap_eq_append_iff {f : α → Option β} :
     filterMap f l = L₁ ++ L₂ ↔ ∃ l₁ l₂, l = l₁ ++ l₂ ∧ filterMap f l₁ = L₁ ∧ filterMap f l₂ = L₂ := by
   constructor
@@ -1924,6 +2119,14 @@ theorem head?_flatten {L : List (List α)} : (flatten L).head? = L.findSome? fun
 -- `getLast?_flatten` is proved later, after the `reverse` section.
 -- `head_flatten` and `getLast_flatten` are proved in `Init.Data.List.Find`.
 
+theorem foldl_flatten (f : β → α → β) (b : β) (L : List (List α)) :
+    (flatten L).foldl f b = L.foldl (fun b l => l.foldl f b) b := by
+  induction L generalizing b <;> simp_all
+
+theorem foldr_flatten (f : α → β → β) (b : β) (L : List (List α)) :
+    (flatten L).foldr f b = L.foldr (fun l b => l.foldr f b) b := by
+  induction L <;> simp_all
+
 @[simp] theorem map_flatten (f : α → β) (L : List (List α)) : map f (flatten L) = flatten (map (map f) L) := by
   induction L <;> simp_all
 
@@ -1985,8 +2188,8 @@ theorem flatten_eq_append_iff {xs : List (List α)} {ys zs : List α} :
   constructor
   · induction xs generalizing ys with
     | nil =>
-      simp only [flatten_nil, nil_eq, append_eq_nil_iff, and_false, cons_append, false_and,
-        exists_const, exists_false, or_false, and_imp, List.cons_ne_nil]
+      simp only [flatten_nil, nil_eq, append_eq_nil, and_false, cons_append, false_and, exists_const,
+        exists_false, or_false, and_imp, List.cons_ne_nil]
       rintro rfl rfl
       exact ⟨[], [], by simp⟩
     | cons x xs ih =>
@@ -2496,114 +2699,10 @@ theorem flatMap_reverse {β} (l : List α) (f : α → List β) : (l.reverse.fla
 @[simp] theorem reverseAux_eq (as bs : List α) : reverseAux as bs = reverse as ++ bs :=
   reverseAux_eq_append ..
 
-@[simp] theorem reverse_replicate (n) (a : α) : reverse (replicate n a) = replicate n a :=
-  eq_replicate_iff.2
-    ⟨by rw [length_reverse, length_replicate],
-     fun _ h => eq_of_mem_replicate (mem_reverse.1 h)⟩
-
-
-/-! ### foldlM and foldrM -/
-
-@[simp] theorem foldlM_append [Monad m] [LawfulMonad m] (f : β → α → m β) (b) (l l' : List α) :
-    (l ++ l').foldlM f b = l.foldlM f b >>= l'.foldlM f := by
-  induction l generalizing b <;> simp [*]
-
-@[simp] theorem foldrM_cons [Monad m] [LawfulMonad m] (a : α) (l) (f : α → β → m β) (b) :
-    (a :: l).foldrM f b = l.foldrM f b >>= f a := by
-  simp only [foldrM]
-  induction l <;> simp_all
-
-theorem foldl_eq_foldlM (f : β → α → β) (b) (l : List α) :
-    l.foldl f b = l.foldlM (m := Id) f b := by
-  induction l generalizing b <;> simp [*, foldl]
-
-theorem foldr_eq_foldrM (f : α → β → β) (b) (l : List α) :
-    l.foldr f b = l.foldrM (m := Id) f b := by
-  induction l <;> simp [*, foldr]
-
-@[simp] theorem id_run_foldlM (f : β → α → Id β) (b) (l : List α) :
-    Id.run (l.foldlM f b) = l.foldl f b := (foldl_eq_foldlM f b l).symm
-
-@[simp] theorem id_run_foldrM (f : α → β → Id β) (b) (l : List α) :
-    Id.run (l.foldrM f b) = l.foldr f b := (foldr_eq_foldrM f b l).symm
-
-@[simp] theorem foldlM_reverse [Monad m] (l : List α) (f : β → α → m β) (b) :
-    l.reverse.foldlM f b = l.foldrM (fun x y => f y x) b := rfl
-
 @[simp] theorem foldrM_reverse [Monad m] (l : List α) (f : α → β → m β) (b) :
     l.reverse.foldrM f b = l.foldlM (fun x y => f y x) b :=
   (foldlM_reverse ..).symm.trans <| by simp
 
-/-! ### foldl and foldr -/
-
-@[simp] theorem foldr_cons_eq_append (l : List α) : l.foldr cons l' = l ++ l' := by
-  induction l <;> simp [*]
-
-@[deprecated foldr_cons_eq_append (since := "2024-08-22")] abbrev foldr_self_append := @foldr_cons_eq_append
-
-@[simp] theorem foldl_flip_cons_eq_append (l : List α) : l.foldl (fun x y => y :: x) l' = l.reverse ++ l' := by
-  induction l generalizing l' <;> simp [*]
-
-theorem foldr_cons_nil (l : List α) : l.foldr cons [] = l := by simp
-
-@[deprecated foldr_cons_nil (since := "2024-09-04")] abbrev foldr_self := @foldr_cons_nil
-
-theorem foldl_map (f : β₁ → β₂) (g : α → β₂ → α) (l : List β₁) (init : α) :
-    (l.map f).foldl g init = l.foldl (fun x y => g x (f y)) init := by
-  induction l generalizing init <;> simp [*]
-
-theorem foldr_map (f : α₁ → α₂) (g : α₂ → β → β) (l : List α₁) (init : β) :
-    (l.map f).foldr g init = l.foldr (fun x y => g (f x) y) init := by
-  induction l generalizing init <;> simp [*]
-
-theorem foldl_filterMap (f : α → Option β) (g : γ → β → γ) (l : List α) (init : γ) :
-    (l.filterMap f).foldl g init = l.foldl (fun x y => match f y with | some b => g x b | none => x) init := by
-  induction l generalizing init with
-  | nil => rfl
-  | cons a l ih =>
-    simp only [filterMap_cons, foldl_cons]
-    cases f a <;> simp [ih]
-
-theorem foldr_filterMap (f : α → Option β) (g : β → γ → γ) (l : List α) (init : γ) :
-    (l.filterMap f).foldr g init = l.foldr (fun x y => match f x with | some b => g b y | none => y) init := by
-  induction l generalizing init with
-  | nil => rfl
-  | cons a l ih =>
-    simp only [filterMap_cons, foldr_cons]
-    cases f a <;> simp [ih]
-
-theorem foldl_map' (g : α → β) (f : α → α → α) (f' : β → β → β) (a : α) (l : List α)
-    (h : ∀ x y, f' (g x) (g y) = g (f x y)) :
-    (l.map g).foldl f' (g a) = g (l.foldl f a) := by
-  induction l generalizing a
-  · simp
-  · simp [*, h]
-
-theorem foldr_map' (g : α → β) (f : α → α → α) (f' : β → β → β) (a : α) (l : List α)
-    (h : ∀ x y, f' (g x) (g y) = g (f x y)) :
-    (l.map g).foldr f' (g a) = g (l.foldr f a) := by
-  induction l generalizing a
-  · simp
-  · simp [*, h]
-
-@[simp] theorem foldrM_append [Monad m] [LawfulMonad m] (f : α → β → m β) (b) (l l' : List α) :
-    (l ++ l').foldrM f b = l'.foldrM f b >>= l.foldrM f := by
-  induction l <;> simp [*]
-
-@[simp] theorem foldl_append {β : Type _} (f : β → α → β) (b) (l l' : List α) :
-    (l ++ l').foldl f b = l'.foldl f (l.foldl f b) := by simp [foldl_eq_foldlM]
-
-@[simp] theorem foldr_append (f : α → β → β) (b) (l l' : List α) :
-    (l ++ l').foldr f b = l.foldr f (l'.foldr f b) := by simp [foldr_eq_foldrM]
-
-theorem foldl_flatten (f : β → α → β) (b : β) (L : List (List α)) :
-    (flatten L).foldl f b = L.foldl (fun b l => l.foldl f b) b := by
-  induction L generalizing b <;> simp_all
-
-theorem foldr_flatten (f : α → β → β) (b : β) (L : List (List α)) :
-    (flatten L).foldr f b = L.foldr (fun l b => l.foldr f b) b := by
-  induction L <;> simp_all
-
 @[simp] theorem foldl_reverse (l : List α) (f : β → α → β) (b) :
     l.reverse.foldl f b = l.foldr (fun x y => f y x) b := by simp [foldl_eq_foldlM, foldr_eq_foldrM]
 
@@ -2617,127 +2716,10 @@ theorem foldl_eq_foldr_reverse (l : List α) (f : β → α → β) (b) :
 theorem foldr_eq_foldl_reverse (l : List α) (f : α → β → β) (b) :
     l.foldr f b = l.reverse.foldl (fun x y => f y x) b := by simp
 
-theorem foldl_assoc {op : α → α → α} [ha : Std.Associative op] :
-    ∀ {l : List α} {a₁ a₂}, l.foldl op (op a₁ a₂) = op a₁ (l.foldl op a₂)
-  | [], a₁, a₂ => rfl
-  | a :: l, a₁, a₂ => by
-    simp only [foldl_cons, ha.assoc]
-    rw [foldl_assoc]
-
-theorem foldr_assoc {op : α → α → α} [ha : Std.Associative op] :
-    ∀ {l : List α} {a₁ a₂}, l.foldr op (op a₁ a₂) = op (l.foldr op a₁) a₂
-  | [], a₁, a₂ => rfl
-  | a :: l, a₁, a₂ => by
-    simp only [foldr_cons, ha.assoc]
-    rw [foldr_assoc]
-
-theorem foldl_hom (f : α₁ → α₂) (g₁ : α₁ → β → α₁) (g₂ : α₂ → β → α₂) (l : List β) (init : α₁)
-    (H : ∀ x y, g₂ (f x) y = f (g₁ x y)) : l.foldl g₂ (f init) = f (l.foldl g₁ init) := by
-  induction l generalizing init <;> simp [*, H]
-
-theorem foldr_hom (f : β₁ → β₂) (g₁ : α → β₁ → β₁) (g₂ : α → β₂ → β₂) (l : List α) (init : β₁)
-    (H : ∀ x y, g₂ x (f y) = f (g₁ x y)) : l.foldr g₂ (f init) = f (l.foldr g₁ init) := by
-  induction l <;> simp [*, H]
-
-/--
-Prove a proposition about the result of `List.foldl`,
-by proving it for the initial data,
-and the implication that the operation applied to any element of the list preserves the property.
-
-The motive can take values in `Sort _`, so this may be used to construct data,
-as well as to prove propositions.
--/
-def foldlRecOn {motive : β → Sort _} : ∀ (l : List α) (op : β → α → β) (b : β) (_ : motive b)
-    (_ : ∀ (b : β) (_ : motive b) (a : α) (_ : a ∈ l), motive (op b a)), motive (List.foldl op b l)
-  | [], _, _, hb, _ => hb
-  | hd :: tl, op, b, hb, hl =>
-    foldlRecOn tl op (op b hd) (hl b hb hd (mem_cons_self hd tl))
-      fun y hy x hx => hl y hy x (mem_cons_of_mem hd hx)
-
-@[simp] theorem foldlRecOn_nil {motive : β → Sort _} (hb : motive b)
-    (hl : ∀ (b : β) (_ : motive b) (a : α) (_ : a ∈ []), motive (op b a)) :
-    foldlRecOn [] op b hb hl = hb := rfl
-
-@[simp] theorem foldlRecOn_cons {motive : β → Sort _} (hb : motive b)
-    (hl : ∀ (b : β) (_ : motive b) (a : α) (_ : a ∈ x :: l), motive (op b a)) :
-    foldlRecOn (x :: l) op b hb hl =
-      foldlRecOn l op (op b x) (hl b hb x (mem_cons_self x l))
-        (fun b c a m => hl b c a (mem_cons_of_mem x m)) :=
-  rfl
-
-/--
-Prove a proposition about the result of `List.foldr`,
-by proving it for the initial data,
-and the implication that the operation applied to any element of the list preserves the property.
-
-The motive can take values in `Sort _`, so this may be used to construct data,
-as well as to prove propositions.
--/
-def foldrRecOn {motive : β → Sort _} : ∀ (l : List α) (op : α → β → β) (b : β) (_ : motive b)
-    (_ : ∀ (b : β) (_ : motive b) (a : α) (_ : a ∈ l), motive (op a b)), motive (List.foldr op b l)
-  | nil, _, _, hb, _ => hb
-  | x :: l, op, b, hb, hl =>
-    hl (foldr op b l)
-      (foldrRecOn l op b hb fun b c a m => hl b c a (mem_cons_of_mem x m)) x (mem_cons_self x l)
-
-@[simp] theorem foldrRecOn_nil {motive : β → Sort _} (hb : motive b)
-    (hl : ∀ (b : β) (_ : motive b) (a : α) (_ : a ∈ []), motive (op a b)) :
-    foldrRecOn [] op b hb hl = hb := rfl
-
-@[simp] theorem foldrRecOn_cons {motive : β → Sort _} (hb : motive b)
-    (hl : ∀ (b : β) (_ : motive b) (a : α) (_ : a ∈ x :: l), motive (op a b)) :
-    foldrRecOn (x :: l) op b hb hl =
-      hl _ (foldrRecOn l op b hb fun b c a m => hl b c a (mem_cons_of_mem x m))
-        x (mem_cons_self x l) :=
-  rfl
-
-/--
-We can prove that two folds over the same list are related (by some arbitrary relation)
-if we know that the initial elements are related and the folding function, for each element of the list,
-preserves the relation.
--/
-theorem foldl_rel {l : List α} {f g : β → α → β} {a b : β} (r : β → β → Prop)
-    (h : r a b) (h' : ∀ (a : α), a ∈ l → ∀ (c c' : β), r c c' → r (f c a) (g c' a)) :
-    r (l.foldl (fun acc a => f acc a) a) (l.foldl (fun acc a => g acc a) b) := by
-  induction l generalizing a b with
-  | nil => simp_all
-  | cons a l ih =>
-    simp only [foldl_cons]
-    apply ih
-    · simp_all
-    · exact fun a m c c' h => h' _ (by simp_all) _ _ h
-
-/--
-We can prove that two folds over the same list are related (by some arbitrary relation)
-if we know that the initial elements are related and the folding function, for each element of the list,
-preserves the relation.
--/
-theorem foldr_rel {l : List α} {f g : α → β → β} {a b : β} (r : β → β → Prop)
-    (h : r a b) (h' : ∀ (a : α), a ∈ l → ∀ (c c' : β), r c c' → r (f a c) (g a c')) :
-    r (l.foldr (fun a acc => f a acc) a) (l.foldr (fun a acc => g a acc) b) := by
-  induction l generalizing a b with
-  | nil => simp_all
-  | cons a l ih =>
-    simp only [foldr_cons]
-    apply h'
-    · simp
-    · exact ih h fun a m c c' h => h' _ (by simp_all) _ _ h
-
-@[simp] theorem foldl_add_const (l : List α) (a b : Nat) :
-    l.foldl (fun x _ => x + a) b = b + a * l.length := by
-  induction l generalizing b with
-  | nil => simp
-  | cons y l ih =>
-    simp only [foldl_cons, ih, length_cons, Nat.mul_add, Nat.mul_one, Nat.add_assoc,
-      Nat.add_comm a]
-
-@[simp] theorem foldr_add_const (l : List α) (a b : Nat) :
-    l.foldr (fun _ x => x + a) b = b + a * l.length := by
-  induction l generalizing b with
-  | nil => simp
-  | cons y l ih =>
-    simp only [foldr_cons, ih, length_cons, Nat.mul_add, Nat.mul_one, Nat.add_assoc]
-
+@[simp] theorem reverse_replicate (n) (a : α) : reverse (replicate n a) = replicate n a :=
+  eq_replicate_iff.2
+    ⟨by rw [length_reverse, length_replicate],
+     fun _ h => eq_of_mem_replicate (mem_reverse.1 h)⟩
 
 /-! #### Further results about `getLast` and `getLast?` -/
 

src/Init/Data/List/Perm.lean

@@ -510,18 +510,4 @@ theorem Perm.eraseP (f : α → Bool) {l₁ l₂ : List α}
     refine (IH₁ H).trans (IH₂ ((p₁.pairwise_iff ?_).1 H))
     exact fun h h₁ h₂ => h h₂ h₁
 
-theorem perm_insertIdx {α} (x : α) (l : List α) {n} (h : n ≤ l.length) :
-    insertIdx n x l ~ x :: l := by
-  induction l generalizing n with
-  | nil =>
-    cases n with
-    | zero => rfl
-    | succ => cases h
-  | cons _ _ ih =>
-    cases n with
-    | zero => simp [insertIdx]
-    | succ =>
-      simp only [insertIdx, modifyTailIdx]
-      refine .trans (.cons _ (ih (Nat.le_of_succ_le_succ h))) (.swap ..)
-
 end List

src/Init/Data/List/Sort/Lemmas.lean

@@ -253,10 +253,6 @@ theorem merge_perm_append : ∀ {xs ys : List α}, merge xs ys le ~ xs ++ ys
     · exact (merge_perm_append.cons y).trans
         ((Perm.swap x y _).trans (perm_middle.symm.cons x))
 
-theorem Perm.merge (s₁ s₂ : α → α → Bool) (hl : l₁ ~ l₂) (hr : r₁ ~ r₂) :
-    merge l₁ r₁ s₁ ~ merge l₂ r₂ s₂ :=
-  Perm.trans (merge_perm_append ..) <| Perm.trans (Perm.append hl hr) <| Perm.symm (merge_perm_append ..)
-
 /-! ### mergeSort -/
 
 @[simp] theorem mergeSort_nil : [].mergeSort r = [] := by rw [List.mergeSort]

src/Init/Data/List/ToArray.lean

@@ -46,7 +46,7 @@ theorem toArray_cons (a : α) (l : List α) : (a :: l).toArray = #[a] ++ l.toArr
 @[simp] theorem isEmpty_toArray (l : List α) : l.toArray.isEmpty = l.isEmpty := by
   cases l <;> simp [Array.isEmpty]
 
-@[simp] theorem toArray_singleton (a : α) : (List.singleton a).toArray = Array.singleton a := rfl
+@[simp] theorem toArray_singleton (a : α) : (List.singleton a).toArray = singleton a := rfl
 
 @[simp] theorem back!_toArray [Inhabited α] (l : List α) : l.toArray.back! = l.getLast! := by
   simp only [back!, size_toArray, Array.get!_eq_getElem!, getElem!_toArray, getLast!_eq_getElem!]

src/Init/Data/List/Zip.lean

@@ -203,11 +203,11 @@ theorem zipWith_eq_append_iff {f : α → β → γ} {l₁ : List α} {l₂ : Li
     cases l₂ with
     | nil =>
       constructor
-      · simp only [zipWith_nil_right, nil_eq, append_eq_nil_iff, exists_and_left, and_imp]
+      · simp only [zipWith_nil_right, nil_eq, append_eq_nil, exists_and_left, and_imp]
         rintro rfl  rfl
         exact ⟨[], x₁ :: l₁, [], by simp⟩
       · rintro ⟨w, x, y, z, h₁, _, h₃, rfl, rfl⟩
-        simp only [nil_eq, append_eq_nil_iff] at h₃
+        simp only [nil_eq, append_eq_nil] at h₃
         obtain ⟨rfl, rfl⟩ := h₃
         simp
     | cons x₂ l₂ =>

src/Init/Data/Nat/Div/Lemmas.lean

@@ -49,17 +49,4 @@ theorem lt_div_mul_self (h : 0 < k) (w : k ≤ x) : x - k < x / k * k := by
   have : x % k < k := mod_lt x h
   omega
 
-theorem div_pos (hba : b ≤ a) (hb : 0 < b) : 0 < a / b := by
-  cases b
-  · contradiction
-  · simp [Nat.pos_iff_ne_zero, div_eq_zero_iff_lt, hba]
-
-theorem div_le_div_left (hcb : c ≤ b) (hc : 0 < c) : a / b ≤ a / c :=
-  (Nat.le_div_iff_mul_le hc).2 <|
-    Nat.le_trans (Nat.mul_le_mul_left _ hcb) (Nat.div_mul_le_self a b)
-
-theorem div_add_le_right {z : Nat} (h : 0 < z) (x y : Nat) :
-    x / (y + z) ≤ x / z :=
-  div_le_div_left (Nat.le_add_left z y) h
-
 end Nat

src/Init/Data/UInt/Basic.lean

@@ -159,8 +159,6 @@ def UInt32.xor (a b : UInt32) : UInt32 := ⟨a.toBitVec ^^^ b.toBitVec⟩
 def UInt32.shiftLeft (a b : UInt32) : UInt32 := ⟨a.toBitVec <<< (mod b 32).toBitVec⟩
 @[extern "lean_uint32_shift_right"]
 def UInt32.shiftRight (a b : UInt32) : UInt32 := ⟨a.toBitVec >>> (mod b 32).toBitVec⟩
-def UInt32.lt (a b : UInt32) : Prop := a.toBitVec < b.toBitVec
-def UInt32.le (a b : UInt32) : Prop := a.toBitVec ≤ b.toBitVec
 
 instance : Add UInt32       := ⟨UInt32.add⟩
 instance : Sub UInt32       := ⟨UInt32.sub⟩
@@ -171,8 +169,6 @@ set_option linter.deprecated false in
 instance : HMod UInt32 Nat UInt32 := ⟨UInt32.modn⟩
 
 instance : Div UInt32       := ⟨UInt32.div⟩
-instance : LT UInt32        := ⟨UInt32.lt⟩
-instance : LE UInt32        := ⟨UInt32.le⟩
 
 @[extern "lean_uint32_complement"]
 def UInt32.complement (a : UInt32) : UInt32 := ⟨~~~a.toBitVec⟩

src/Init/Data/UInt/Bitwise.lean

@@ -13,12 +13,6 @@ macro "declare_bitwise_uint_theorems" typeName:ident bits:term:arg : command =>
 `(
 namespace $typeName
 
-@[simp] protected theorem toBitVec_add {a b : $typeName} : (a + b).toBitVec = a.toBitVec + b.toBitVec := rfl
-@[simp] protected theorem toBitVec_sub {a b : $typeName} : (a - b).toBitVec = a.toBitVec - b.toBitVec := rfl
-@[simp] protected theorem toBitVec_mul {a b : $typeName} : (a * b).toBitVec = a.toBitVec * b.toBitVec := rfl
-@[simp] protected theorem toBitVec_div {a b : $typeName} : (a / b).toBitVec = a.toBitVec / b.toBitVec := rfl
-@[simp] protected theorem toBitVec_mod {a b : $typeName} : (a % b).toBitVec = a.toBitVec % b.toBitVec := rfl
-@[simp] protected theorem toBitVec_not {a : $typeName} : (~~~a).toBitVec = ~~~a.toBitVec := rfl
 @[simp] protected theorem toBitVec_and (a b : $typeName) : (a &&& b).toBitVec = a.toBitVec &&& b.toBitVec := rfl
 @[simp] protected theorem toBitVec_or (a b : $typeName) : (a ||| b).toBitVec = a.toBitVec ||| b.toBitVec := rfl
 @[simp] protected theorem toBitVec_xor (a b : $typeName) : (a ^^^ b).toBitVec = a.toBitVec ^^^ b.toBitVec := rfl
@@ -43,31 +37,3 @@ declare_bitwise_uint_theorems UInt16 16
 declare_bitwise_uint_theorems UInt32 32
 declare_bitwise_uint_theorems UInt64 64
 declare_bitwise_uint_theorems USize System.Platform.numBits
-
-@[simp]
-theorem Bool.toBitVec_toUInt8 {b : Bool} :
-    b.toUInt8.toBitVec = (BitVec.ofBool b).setWidth 8 := by
-  cases b <;> simp [toUInt8]
-
-@[simp]
-theorem Bool.toBitVec_toUInt16 {b : Bool} :
-    b.toUInt16.toBitVec = (BitVec.ofBool b).setWidth 16 := by
-  cases b <;> simp [toUInt16]
-
-@[simp]
-theorem Bool.toBitVec_toUInt32 {b : Bool} :
-    b.toUInt32.toBitVec = (BitVec.ofBool b).setWidth 32 := by
-  cases b <;> simp [toUInt32]
-
-@[simp]
-theorem Bool.toBitVec_toUInt64 {b : Bool} :
-    b.toUInt64.toBitVec = (BitVec.ofBool b).setWidth 64 := by
-  cases b <;> simp [toUInt64]
-
-@[simp]
-theorem Bool.toBitVec_toUSize {b : Bool} :
-    b.toUSize.toBitVec = (BitVec.ofBool b).setWidth System.Platform.numBits := by
-  cases b
-  · simp [toUSize]
-  · apply BitVec.eq_of_toNat_eq
-    simp [toUSize]

src/Init/Data/Vector/Basic.lean

@@ -103,7 +103,7 @@ of bounds.
 @[inline] def head [NeZero n] (v : Vector α n) := v[0]'(Nat.pos_of_neZero n)
 
 /-- Push an element `x` to the end of a vector. -/
-@[inline] def push (v : Vector α n) (x : α) : Vector α (n + 1) :=
+@[inline] def push (x : α) (v : Vector α n)  : Vector α (n + 1) :=
   ⟨v.toArray.push x, by simp⟩
 
 /-- Remove the last element of a vector. -/
@@ -136,18 +136,6 @@ This will perform the update destructively provided that the vector has a refere
 @[inline] def set! (v : Vector α n) (i : Nat) (x : α) : Vector α n :=
   ⟨v.toArray.set! i x, by simp⟩
 
-@[inline] def foldlM [Monad m] (f : β → α → m β) (b : β) (v : Vector α n) : m β :=
-  v.toArray.foldlM f b
-
-@[inline] def foldrM [Monad m] (f : α → β → m β) (b : β) (v : Vector α n) : m β :=
-  v.toArray.foldrM f b
-
-@[inline] def foldl (f : β → α → β) (b : β) (v : Vector α n) : β :=
-  v.toArray.foldl f b
-
-@[inline] def foldr (f : α → β → β) (b : β) (v : Vector α n) : β :=
-  v.toArray.foldr f b
-
 /-- Append two vectors. -/
 @[inline] def append (v : Vector α n) (w : Vector α m) : Vector α (n + m) :=
   ⟨v.toArray ++ w.toArray, by simp⟩

src/Init/Data/Vector/Lemmas.lean

@@ -1,7 +1,7 @@
 /-
 Copyright (c) 2024 Shreyas Srinivas. All rights reserved.
 Released under Apache 2.0 license as described in the file LICENSE.
-Authors: Shreyas Srinivas, Francois Dorais, Kim Morrison
+Authors: Shreyas Srinivas, Francois Dorais
 -/
 prelude
 import Init.Data.Vector.Basic
@@ -66,18 +66,6 @@ theorem toArray_mk (a : Array α) (h : a.size = n) : (Vector.mk a h).toArray = a
 @[simp] theorem back?_mk (a : Array α) (h : a.size = n) :
     (Vector.mk a h).back? = a.back? := rfl
 
-@[simp] theorem foldlM_mk [Monad m] (f : β → α → m β) (b : β) (a : Array α) (h : a.size = n) :
-    (Vector.mk a h).foldlM f b = a.foldlM f b := rfl
-
-@[simp] theorem foldrM_mk [Monad m] (f : α → β → m β) (b : β) (a : Array α) (h : a.size = n) :
-    (Vector.mk a h).foldrM f b = a.foldrM f b := rfl
-
-@[simp] theorem foldl_mk (f : β → α → β) (b : β) (a : Array α) (h : a.size = n) :
-    (Vector.mk a h).foldl f b = a.foldl f b := rfl
-
-@[simp] theorem foldr_mk (f : α → β → β) (b : β) (a : Array α) (h : a.size = n) :
-    (Vector.mk a h).foldr f b = a.foldr f b := rfl
-
 @[simp] theorem drop_mk (a : Array α) (h : a.size = n) (m) :
     (Vector.mk a h).drop m = Vector.mk (a.extract m a.size) (by simp [h]) := rfl
 
@@ -153,14 +141,6 @@ theorem toArray_mk (a : Array α) (h : a.size = n) : (Vector.mk a h).toArray = a
 @[simp] theorem all_mk (p : α → Bool) (a : Array α) (h : a.size = n) :
     (Vector.mk a h).all p = a.all p := rfl
 
-@[simp] theorem eq_mk : v = Vector.mk a h ↔ v.toArray = a := by
-  cases v
-  simp
-
-@[simp] theorem mk_eq : Vector.mk a h = v ↔ a = v.toArray := by
-  cases v
-  simp
-
 /-! ### toArray lemmas -/
 
 @[simp] theorem getElem_toArray {α n} (xs : Vector α n) (i : Nat) (h : i < xs.toArray.size) :
@@ -693,24 +673,6 @@ theorem forall_getElem {l : Vector α n} {p : α → Prop} :
   rcases l with ⟨l, rfl⟩
   simp [Array.forall_getElem]
 
-
-/-! ### cast -/
-
-@[simp] theorem getElem_cast (a : Vector α n) (h : n = m) (i : Nat) (hi : i < m) :
-    (a.cast h)[i] = a[i] := by
-  cases a
-  simp
-
-@[simp] theorem getElem?_cast {l : Vector α n} {m : Nat} {w : n = m} {i : Nat} :
-    (l.cast w)[i]? = l[i]? := by
-  rcases l with ⟨l, rfl⟩
-  simp
-
-@[simp] theorem mem_cast {a : α} {l : Vector α n} {m : Nat} {w : n = m} :
-    a ∈ l.cast w ↔ a ∈ l := by
-  rcases l with ⟨l, rfl⟩
-  simp
-
 /-! ### Decidability of bounded quantifiers -/
 
 instance {xs : Vector α n} {p : α → Prop} [DecidablePred p] :
@@ -1061,12 +1023,11 @@ theorem mem_setIfInBounds (v : Vector α n) (i : Nat) (hi : i < n) (a : α) :
   cases l₂
   simp
 
-/-! ### map -/
+/-! Content below this point has not yet been aligned with `List` and `Array`. -/
 
-@[simp] theorem getElem_map (f : α → β) (a : Vector α n) (i : Nat) (hi : i < n) :
-    (a.map f)[i] = f a[i] := by
-  cases a
-  simp
+@[simp] theorem getElem_ofFn {α n} (f : Fin n → α) (i : Nat) (h : i < n) :
+    (Vector.ofFn f)[i] = f ⟨i, by simpa using h⟩ := by
+  simp [ofFn]
 
 /-- The empty vector maps to the empty vector. -/
 @[simp]
@@ -1074,344 +1035,6 @@ theorem map_empty (f : α → β) : map f #v[] = #v[] := by
   rw [map, mk.injEq]
   exact Array.map_empty f
 
-@[simp] theorem map_push {f : α → β} {as : Vector α n} {x : α} :
-    (as.push x).map f = (as.map f).push (f x) := by
-  cases as
-  simp
-
-@[simp] theorem map_id_fun : map (n := n) (id : α → α) = id := by
-  funext l
-  induction l <;> simp_all
-
-/-- `map_id_fun'` differs from `map_id_fun` by representing the identity function as a lambda, rather than `id`. -/
-@[simp] theorem map_id_fun' : map (n := n) (fun (a : α) => a) = id := map_id_fun
-
--- This is not a `@[simp]` lemma because `map_id_fun` will apply.
-theorem map_id (l : Vector α n) : map (id : α → α) l = l := by
-  cases l <;> simp_all
-
-/-- `map_id'` differs from `map_id` by representing the identity function as a lambda, rather than `id`. -/
--- This is not a `@[simp]` lemma because `map_id_fun'` will apply.
-theorem map_id' (l : Vector α n) : map (fun (a : α) => a) l = l := map_id l
-
-/-- Variant of `map_id`, with a side condition that the function is pointwise the identity. -/
-theorem map_id'' {f : α → α} (h : ∀ x, f x = x) (l : Vector α n) : map f l = l := by
-  simp [show f = id from funext h]
-
-theorem map_singleton (f : α → β) (a : α) : map f #v[a] = #v[f a] := rfl
-
-@[simp] theorem mem_map {f : α → β} {l : Vector α n} : b ∈ l.map f ↔ ∃ a, a ∈ l ∧ f a = b := by
-  cases l
-  simp
-
-theorem exists_of_mem_map (h : b ∈ map f l) : ∃ a, a ∈ l ∧ f a = b := mem_map.1 h
-
-theorem mem_map_of_mem (f : α → β) (h : a ∈ l) : f a ∈ map f l := mem_map.2 ⟨_, h, rfl⟩
-
-theorem forall_mem_map {f : α → β} {l : Vector α n} {P : β → Prop} :
-    (∀ (i) (_ : i ∈ l.map f), P i) ↔ ∀ (j) (_ : j ∈ l), P (f j) := by
-  simp
-
-@[simp] theorem map_inj_left {f g : α → β} : map f l = map g l ↔ ∀ a ∈ l, f a = g a := by
-  cases l <;> simp_all
-
-theorem map_congr_left (h : ∀ a ∈ l, f a = g a) : map f l = map g l :=
-  map_inj_left.2 h
-
-theorem map_inj [NeZero n] : map (n := n) f = map g ↔ f = g := by
-  constructor
-  · intro h
-    ext a
-    replace h := congrFun h (mkVector n a)
-    simp only [mkVector, map_mk, mk.injEq, Array.map_inj_left, Array.mem_mkArray,  and_imp,
-      forall_eq_apply_imp_iff] at h
-    exact h (NeZero.ne n)
-  · intro h; subst h; rfl
-
-theorem map_eq_push_iff {f : α → β} {l : Vector α (n + 1)} {l₂ : Vector β n} {b : β} :
-    map f l = l₂.push b ↔ ∃ l₁ a, l = l₁.push a ∧ map f l₁ = l₂ ∧ f a = b := by
-  rcases l with ⟨l, h⟩
-  rcases l₂ with ⟨l₂, rfl⟩
-  simp only [map_mk, push_mk, mk.injEq, Array.map_eq_push_iff]
-  constructor
-  · rintro ⟨l₁, a, rfl, rfl, rfl⟩
-    refine ⟨⟨l₁, by simp⟩, a, by simp⟩
-  · rintro ⟨l₁, a, h₁, h₂, rfl⟩
-    refine ⟨l₁.toArray, a, by simp_all⟩
-
-@[simp] theorem map_eq_singleton_iff {f : α → β} {l : Vector α 1} {b : β} :
-    map f l = #v[b] ↔ ∃ a, l = #v[a] ∧ f a = b := by
-  cases l
-  simp
-
-theorem map_eq_map_iff {f g : α → β} {l : Vector α n} :
-    map f l = map g l ↔ ∀ a ∈ l, f a = g a := by
-  cases l <;> simp_all
-
-theorem map_eq_iff {f : α → β} {l : Vector α n} {l' : Vector β n} :
-    map f l = l' ↔ ∀ i (h : i < n), l'[i] = f l[i] := by
-  rcases l with ⟨l, rfl⟩
-  rcases l' with ⟨l', h'⟩
-  simp only [map_mk, eq_mk, Array.map_eq_iff, getElem_mk]
-  constructor
-  · intro w i h
-    simpa [h, h'] using w i
-  · intro w i
-    if h : i < l.size then
-      simpa [h, h'] using w i h
-    else
-      rw [getElem?_neg, getElem?_neg, Option.map_none'] <;> omega
-
-@[simp] theorem map_set {f : α → β} {l : Vector α n} {i : Nat} {h : i < n} {a : α} :
-    (l.set i a).map f = (l.map f).set i (f a) (by simpa using h) := by
-  cases l
-  simp
-
-@[simp] theorem map_setIfInBounds {f : α → β} {l : Vector α n} {i : Nat} {a : α} :
-    (l.setIfInBounds i a).map f = (l.map f).setIfInBounds i (f a) := by
-  cases l
-  simp
-
-@[simp] theorem map_pop {f : α → β} {l : Vector α n} : l.pop.map f = (l.map f).pop := by
-  cases l
-  simp
-
-@[simp] theorem back?_map {f : α → β} {l : Vector α n} : (l.map f).back? = l.back?.map f := by
-  cases l
-  simp
-
-@[simp] theorem map_map {f : α → β} {g : β → γ} {as : Vector α n} :
-    (as.map f).map g = as.map (g ∘ f) := by
-  cases as
-  simp
-
-/-! ### singleton -/
-
-@[simp] theorem singleton_def (v : α) : Vector.singleton v = #v[v] := rfl
-
-/-! ### append -/
-
-@[simp] theorem append_push {as : Vector α n} {bs : Vector α m} {a : α} :
-    as ++ bs.push a = (as ++ bs).push a := by
-  cases as
-  cases bs
-  simp
-
-theorem singleton_eq_toVector_singleton (a : α) : #v[a] = #[a].toVector := rfl
-
-@[simp] theorem mem_append {a : α} {s : Vector α n} {t : Vector α m} :
-    a ∈ s ++ t ↔ a ∈ s ∨ a ∈ t := by
-  cases s
-  cases t
-  simp
-
-theorem mem_append_left {a : α} {s : Vector α n} {t : Vector α m} (h : a ∈ s) : a ∈ s ++ t :=
-  mem_append.2 (Or.inl h)
-
-theorem mem_append_right {a : α} {s : Vector α n} {t : Vector α m} (h : a ∈ t) : a ∈ s ++ t :=
-  mem_append.2 (Or.inr h)
-
-theorem not_mem_append {a : α} {s : Vector α n} {t : Vector α m} (h₁ : a ∉ s) (h₂ : a ∉ t) :
-    a ∉ s ++ t :=
-  mt mem_append.1 $ not_or.mpr ⟨h₁, h₂⟩
-
-/--
-See also `eq_push_append_of_mem`, which proves a stronger version
-in which the initial array must not contain the element.
--/
-theorem append_of_mem {a : α} {l : Vector α n} (h : a ∈ l) :
-    ∃ (m k : Nat) (w : m + 1 + k = n) (s : Vector α m) (t : Vector α k),
-      l = (s.push a ++ t).cast w := by
-  rcases l with ⟨l, rfl⟩
-  obtain ⟨s, t, rfl⟩ := Array.append_of_mem (by simpa using h)
-  refine ⟨_, _, by simp, s.toVector, t.toVector, by simp_all⟩
-
-theorem mem_iff_append {a : α} {l : Vector α n} :
-    a ∈ l ↔ ∃ (m k : Nat) (w : m + 1 + k = n) (s : Vector α m) (t : Vector α k),
-      l = (s.push a ++ t).cast w :=
-  ⟨append_of_mem, by rintro ⟨m, k, rfl, s, t, rfl⟩; simp⟩
-
-theorem forall_mem_append {p : α → Prop} {l₁ : Vector α n} {l₂ : Vector α m} :
-    (∀ (x) (_ : x ∈ l₁ ++ l₂), p x) ↔ (∀ (x) (_ : x ∈ l₁), p x) ∧ (∀ (x) (_ : x ∈ l₂), p x) := by
-  simp only [mem_append, or_imp, forall_and]
-
-theorem empty_append (as : Vector α n) : (#v[] : Vector α 0) ++ as = as.cast (by omega) := by
-  rcases as with ⟨as, rfl⟩
-  simp
-
-theorem append_empty (as : Vector α n) : as ++ (#v[] : Vector α 0) = as := by
-  rw [← toArray_inj, toArray_append, Array.append_nil]
-
-theorem getElem_append (a : Vector α n) (b : Vector α m) (i : Nat) (hi : i < n + m) :
-    (a ++ b)[i] = if h : i < n then a[i] else b[i - n] := by
-  rcases a with ⟨a, rfl⟩
-  rcases b with ⟨b, rfl⟩
-  simp [Array.getElem_append, hi]
-
-theorem getElem_append_left {a : Vector α n} {b : Vector α m} {i : Nat} (hi : i < n) :
-    (a ++ b)[i] = a[i] := by simp [getElem_append, hi]
-
-theorem getElem_append_right {a : Vector α n} {b : Vector α m} {i : Nat} (h : i < n + m) (hi : n ≤ i) :
-    (a ++ b)[i] = b[i - n] := by
-  rw [getElem_append, dif_neg (by omega)]
-
-theorem getElem?_append_left {as : Vector α n} {bs : Vector α m} {i : Nat} (hn : i < n) :
-    (as ++ bs)[i]? = as[i]? := by
-  have hn' : i < n + m := by omega
-  simp_all [getElem?_eq_getElem, getElem_append]
-
-theorem getElem?_append_right {as : Vector α n} {bs : Vector α m} {i : Nat} (h : n ≤ i) :
-    (as ++ bs)[i]? = bs[i - n]? := by
-  rcases as with ⟨as, rfl⟩
-  rcases bs with ⟨bs, rfl⟩
-  simp [Array.getElem?_append_right, h]
-
-theorem getElem?_append {as : Vector α n} {bs : Vector α m} {i : Nat} :
-    (as ++ bs)[i]? = if i < n then as[i]? else bs[i - n]? := by
-  split <;> rename_i h
-  · exact getElem?_append_left h
-  · exact getElem?_append_right (by simpa using h)
-
-/-- Variant of `getElem_append_left` useful for rewriting from the small array to the big array. -/
-theorem getElem_append_left' (l₁ : Vector α m) {l₂ : Vector α n} {i : Nat} (hi : i < m) :
-    l₁[i] = (l₁ ++ l₂)[i] := by
-  rw [getElem_append_left] <;> simp
-
-/-- Variant of `getElem_append_right` useful for rewriting from the small array to the big array. -/
-theorem getElem_append_right' (l₁ : Vector α m) {l₂ : Vector α n} {i : Nat} (hi : i < n) :
-    l₂[i] = (l₁ ++ l₂)[i + m] := by
-  rw [getElem_append_right] <;> simp [*, Nat.le_add_left]
-
-theorem getElem_of_append {l : Vector α n} {l₁ : Vector α m} {l₂ : Vector α k}
-    (w : m + 1 + k = n) (eq : l = (l₁.push a ++ l₂).cast w) :
-    l[m] = a := Option.some.inj <| by
-  rw [← getElem?_eq_getElem, eq, getElem?_cast, getElem?_append_left (by simp)]
-  simp
-
-@[simp 1100] theorem append_singleton {a : α} {as : Vector α n} : as ++ #v[a] = as.push a := by
-  cases as
-  simp
-
-theorem append_inj {s₁ s₂ : Vector α n} {t₁ t₂ : Vector α m} (h : s₁ ++ t₁ = s₂ ++ t₂) :
-    s₁ = s₂ ∧ t₁ = t₂ := by
-  rcases s₁ with ⟨s₁, rfl⟩
-  rcases s₂ with ⟨s₂, hs⟩
-  rcases t₁ with ⟨t₁, rfl⟩
-  rcases t₂ with ⟨t₂, ht⟩
-  simpa using Array.append_inj (by simpa using h) (by omega)
-
-theorem append_inj_right {s₁ s₂ : Vector α n} {t₁ t₂ : Vector α m}
-    (h : s₁ ++ t₁ = s₂ ++ t₂) : t₁ = t₂ :=
-  (append_inj h).right
-
-theorem append_inj_left {s₁ s₂ : Vector α n} {t₁ t₂ : Vector α m}
-    (h : s₁ ++ t₁ = s₂ ++ t₂) : s₁ = s₂ :=
-  (append_inj h).left
-
-theorem append_right_inj {t₁ t₂ : Vector α m} (s : Vector α n) : s ++ t₁ = s ++ t₂ ↔ t₁ = t₂ :=
-  ⟨fun h => append_inj_right h, congrArg _⟩
-
-theorem append_left_inj {s₁ s₂ : Vector α n} (t : Vector α m) : s₁ ++ t = s₂ ++ t ↔ s₁ = s₂ :=
-  ⟨fun h => append_inj_left h, congrArg (· ++ _)⟩
-
-theorem append_eq_append_iff {a : Vector α n} {b : Vector α m} {c : Vector α k} {d : Vector α l}
-    (w : k + l = n + m) :
-    a ++ b = (c ++ d).cast w ↔
-      if h : n ≤ k then
-        ∃ a' : Vector α (k - n), c = (a ++ a').cast (by omega) ∧ b = (a' ++ d).cast (by omega)
-      else
-        ∃ c' : Vector α (n - k), a = (c ++ c').cast (by omega) ∧ d = (c' ++ b).cast (by omega) := by
-  rcases a with ⟨a, rfl⟩
-  rcases b with ⟨b, rfl⟩
-  rcases c with ⟨c, rfl⟩
-  rcases d with ⟨d, rfl⟩
-  simp only [mk_append_mk, Array.append_eq_append_iff, mk_eq, toArray_cast]
-  constructor
-  · rintro (⟨a', rfl, rfl⟩ | ⟨c', rfl, rfl⟩)
-    · rw [dif_pos (by simp)]
-      exact ⟨a'.toVector.cast (by simp; omega), by simp⟩
-    · split <;> rename_i h
-      · have hc : c'.size = 0 := by simp at h; omega
-        simp at hc
-        exact ⟨#v[].cast (by simp; omega), by simp_all⟩
-      · exact ⟨c'.toVector.cast (by simp; omega), by simp⟩
-  · split <;> rename_i h
-    · rintro ⟨a', hc, rfl⟩
-      left
-      refine ⟨a'.toArray, hc, rfl⟩
-    · rintro ⟨c', ha, rfl⟩
-      right
-      refine ⟨c'.toArray, ha, rfl⟩
-
-theorem set_append {s : Vector α n} {t : Vector α m} {i : Nat} {x : α} (h : i < n + m) :
-    (s ++ t).set i x =
-      if h' : i < n then
-        s.set i x ++ t
-      else
-        s ++ t.set (i - n) x := by
-  rcases s with ⟨s, rfl⟩
-  rcases t with ⟨t, rfl⟩
-  simp only [mk_append_mk, set_mk, Array.set_append]
-  split <;> simp
-
-@[simp] theorem set_append_left {s : Vector α n} {t : Vector α m} {i : Nat} {x : α} (h : i < n) :
-    (s ++ t).set i x = s.set i x ++ t := by
-  simp [set_append, h]
-
-@[simp] theorem set_append_right {s : Vector α n} {t : Vector α m} {i : Nat} {x : α}
-    (h' : i < n + m) (h : n ≤ i) :
-    (s ++ t).set i x = s ++ t.set (i - n) x := by
-  rw [set_append, dif_neg (by omega)]
-
-theorem setIfInBounds_append {s : Vector α n} {t : Vector α m} {i : Nat} {x : α} :
-    (s ++ t).setIfInBounds i x =
-      if i < n then
-        s.setIfInBounds i x ++ t
-      else
-        s ++ t.setIfInBounds (i - n) x := by
-  rcases s with ⟨s, rfl⟩
-  rcases t with ⟨t, rfl⟩
-  simp only [mk_append_mk, setIfInBounds_mk, Array.setIfInBounds_append]
-  split <;> simp
-
-@[simp] theorem setIfInBounds_append_left {s : Vector α n} {t : Vector α m} {i : Nat} {x : α} (h : i < n) :
-    (s ++ t).setIfInBounds i x = s.setIfInBounds i x ++ t := by
-  simp [setIfInBounds_append, h]
-
-@[simp] theorem setIfInBounds_append_right {s : Vector α n} {t : Vector α m} {i : Nat} {x : α}
-    (h : n ≤ i) :
-    (s ++ t).setIfInBounds i x = s ++ t.setIfInBounds (i - n) x := by
-  rw [setIfInBounds_append, if_neg (by omega)]
-
-@[simp] theorem map_append (f : α → β) (l₁ : Vector α n) (l₂ : Vector α m) :
-    map f (l₁ ++ l₂) = map f l₁ ++ map f l₂ := by
-  rcases l₁ with ⟨l₁, rfl⟩
-  rcases l₂ with ⟨l₂, rfl⟩
-  simp
-
-theorem map_eq_append_iff {f : α → β} :
-    map f l = L₁ ++ L₂ ↔ ∃ l₁ l₂, l = l₁ ++ l₂ ∧ map f l₁ = L₁ ∧ map f l₂ = L₂ := by
-  rcases l with ⟨l, h⟩
-  rcases L₁ with ⟨L₁, rfl⟩
-  rcases L₂ with ⟨L₂, rfl⟩
-  simp only [map_mk, mk_append_mk, eq_mk, Array.map_eq_append_iff, mk_eq, toArray_append,
-    toArray_map]
-  constructor
-  · rintro ⟨l₁, l₂, rfl, rfl, rfl⟩
-    exact ⟨l₁.toVector.cast (by simp), l₂.toVector.cast (by simp), by simp⟩
-  · rintro ⟨⟨l₁⟩, ⟨l₂⟩, rfl, h₁, h₂⟩
-    exact ⟨l₁, l₂, by simp_all⟩
-
-theorem append_eq_map_iff {f : α → β} :
-    L₁ ++ L₂ = map f l ↔ ∃ l₁ l₂, l = l₁ ++ l₂ ∧ map f l₁ = L₁ ∧ map f l₂ = L₂ := by
-  rw [eq_comm, map_eq_append_iff]
-
-/-! Content below this point has not yet been aligned with `List` and `Array`. -/
-
-@[simp] theorem getElem_ofFn {α n} (f : Fin n → α) (i : Nat) (h : i < n) :
-    (Vector.ofFn f)[i] = f ⟨i, by simpa using h⟩ := by
-  simp [ofFn]
-
 @[simp] theorem getElem_push_last {v : Vector α n} {x : α} : (v.push x)[n] = x := by
   rcases v with ⟨data, rfl⟩
   simp
@@ -1436,6 +1059,28 @@ defeq issues in the implicit size argument.
     subst h
     simp [pop, back, back!, ← Array.eq_push_pop_back!_of_size_ne_zero]
 
+/-! ### append -/
+
+theorem getElem_append (a : Vector α n) (b : Vector α m) (i : Nat) (hi : i < n + m) :
+    (a ++ b)[i] = if h : i < n then a[i] else b[i - n] := by
+  rcases a with ⟨a, rfl⟩
+  rcases b with ⟨b, rfl⟩
+  simp [Array.getElem_append, hi]
+
+theorem getElem_append_left {a : Vector α n} {b : Vector α m} {i : Nat} (hi : i < n) :
+    (a ++ b)[i] = a[i] := by simp [getElem_append, hi]
+
+theorem getElem_append_right {a : Vector α n} {b : Vector α m} {i : Nat} (h : i < n + m) (hi : n ≤ i) :
+    (a ++ b)[i] = b[i - n] := by
+  rw [getElem_append, dif_neg (by omega)]
+
+/-! ### cast -/
+
+@[simp] theorem getElem_cast (a : Vector α n) (h : n = m) (i : Nat) (hi : i < m) :
+    (a.cast h)[i] = a[i] := by
+  cases a
+  simp
+
 /-! ### extract -/
 
 @[simp] theorem getElem_extract (a : Vector α n) (start stop) (i : Nat) (hi : i < min stop n - start) :
@@ -1443,6 +1088,13 @@ defeq issues in the implicit size argument.
   cases a
   simp
 
+/-! ### map -/
+
+@[simp] theorem getElem_map (f : α → β) (a : Vector α n) (i : Nat) (hi : i < n) :
+    (a.map f)[i] = f a[i] := by
+  cases a
+  simp
+
 /-! ### zipWith -/
 
 @[simp] theorem getElem_zipWith (f : α → β → γ) (a : Vector α n) (b : Vector β n) (i : Nat)
@@ -1451,37 +1103,6 @@ defeq issues in the implicit size argument.
   cases b
   simp
 
-/-! ### foldlM and foldrM -/
-
-@[simp] theorem foldlM_append [Monad m] [LawfulMonad m] (f : β → α → m β) (b) (l : Vector α n) (l' : Vector α n') :
-    (l ++ l').foldlM f b = l.foldlM f b >>= l'.foldlM f := by
-  cases l
-  cases l'
-  simp
-
-@[simp] theorem foldrM_push [Monad m] (f : α → β → m β) (init : β) (l : Vector α n) (a : α) :
-    (l.push a).foldrM f init = f a init >>= l.foldrM f := by
-  cases l
-  simp
-
-theorem foldl_eq_foldlM (f : β → α → β) (b) (l : Vector α n) :
-    l.foldl f b = l.foldlM (m := Id) f b := by
-  cases l
-  simp [Array.foldl_eq_foldlM]
-
-theorem foldr_eq_foldrM (f : α → β → β) (b) (l : Vector α n) :
-    l.foldr f b = l.foldrM (m := Id) f b := by
-  cases l
-  simp [Array.foldr_eq_foldrM]
-
-@[simp] theorem id_run_foldlM (f : β → α → Id β) (b) (l : Vector α n) :
-    Id.run (l.foldlM f b) = l.foldl f b := (foldl_eq_foldlM f b l).symm
-
-@[simp] theorem id_run_foldrM (f : α → β → Id β) (b) (l : Vector α n) :
-    Id.run (l.foldrM f b) = l.foldr f b := (foldr_eq_foldrM f b l).symm
-
-/-! ### foldl and foldr -/
-
 /-! ### take -/
 
 @[simp] theorem take_size (a : Vector α n) : a.take n = a.cast (by simp) := by

src/Init/Grind.lean

@@ -10,5 +10,3 @@ import Init.Grind.Lemmas
 import Init.Grind.Cases
 import Init.Grind.Propagator
 import Init.Grind.Util
-import Init.Grind.Offset
-import Init.Grind.PP

src/Init/Grind/Lemmas.lean

@@ -12,9 +12,6 @@ import Init.Grind.Util
 
 namespace Lean.Grind
 
-theorem rfl_true : true = true :=
-  rfl
-
 theorem intro_with_eq (p p' q : Prop) (he : p = p') (h : p' → q) : p → q :=
   fun hp => h (he.mp hp)
 
@@ -28,9 +25,6 @@ theorem and_eq_of_eq_false_right {a b : Prop} (h : b = False) : (a ∧ b) = Fals
 theorem eq_true_of_and_eq_true_left {a b : Prop} (h : (a ∧ b) = True) : a = True := by simp_all
 theorem eq_true_of_and_eq_true_right {a b : Prop} (h : (a ∧ b) = True) : b = True := by simp_all
 
-theorem or_of_and_eq_false {a b : Prop} (h : (a ∧ b) = False) : (¬a ∨ ¬b) := by
-  by_cases a <;> by_cases b <;> simp_all
-
 /-! Or -/
 
 theorem or_eq_of_eq_true_left {a b : Prop} (h : a = True) : (a ∨ b) = True := by simp [h]
@@ -41,15 +35,6 @@ theorem or_eq_of_eq_false_right {a b : Prop} (h : b = False) : (a ∨ b) = a :=
 theorem eq_false_of_or_eq_false_left {a b : Prop} (h : (a ∨ b) = False) : a = False := by simp_all
 theorem eq_false_of_or_eq_false_right {a b : Prop} (h : (a ∨ b) = False) : b = False := by simp_all
 
-/-! Implies -/
-
-theorem imp_eq_of_eq_false_left {a b : Prop} (h : a = False) : (a → b) = True := by simp [h]
-theorem imp_eq_of_eq_true_right {a b : Prop} (h : b = True) : (a → b) = True := by simp [h]
-theorem imp_eq_of_eq_true_left {a b : Prop} (h : a = True) : (a → b) = b := by simp [h]
-
-theorem eq_true_of_imp_eq_false {a b : Prop} (h : (a → b) = False) : a = True := by simp_all
-theorem eq_false_of_imp_eq_false {a b : Prop} (h : (a → b) = False) : b = False := by simp_all
-
 /-! Not -/
 
 theorem not_eq_of_eq_true {a : Prop} (h : a = True) : (Not a) = False := by simp [h]
@@ -69,12 +54,6 @@ theorem eq_eq_of_eq_true_right {a b : Prop} (h : b = True) : (a = b) = a := by s
 theorem eq_congr  {α : Sort u} {a₁ b₁ a₂ b₂ : α} (h₁ : a₁ = a₂) (h₂ : b₁ = b₂) : (a₁ = b₁) = (a₂ = b₂) := by simp [*]
 theorem eq_congr' {α : Sort u} {a₁ b₁ a₂ b₂ : α} (h₁ : a₁ = b₂) (h₂ : b₁ = a₂) : (a₁ = b₁) = (a₂ = b₂) := by rw [h₁, h₂, Eq.comm (a := a₂)]
 
-/- The following two helper theorems are used to case-split `a = b` representing `iff`. -/
-theorem of_eq_eq_true {a b : Prop} (h : (a = b) = True) : (¬a ∨ b) ∧ (¬b ∨ a) := by
-  by_cases a <;> by_cases b <;> simp_all
-theorem of_eq_eq_false {a b : Prop} (h : (a = b) = False) : (¬a ∨ ¬b) ∧ (b ∨ a) := by
-  by_cases a <;> by_cases b <;> simp_all
-
 /-! Forall -/
 
 theorem forall_propagator (p : Prop) (q : p → Prop) (q' : Prop) (h₁ : p = True) (h₂ : q (of_eq_true h₁) = q') : (∀ hp : p, q hp) = q' := by
@@ -82,28 +61,4 @@ theorem forall_propagator (p : Prop) (q : p → Prop) (q' : Prop) (h₁ : p = Tr
   · intro h'; exact Eq.mp h₂ (h' (of_eq_true h₁))
   · intro h'; intros; exact Eq.mpr h₂ h'
 
-theorem of_forall_eq_false (α : Sort u) (p : α → Prop) (h : (∀ x : α, p x) = False) : ∃ x : α, ¬ p x := by simp_all
-
-/-! dite -/
-
-theorem dite_cond_eq_true' {α : Sort u} {c : Prop} {_ : Decidable c} {a : c → α} {b : ¬ c → α} {r : α} (h₁ : c = True) (h₂ : a (of_eq_true h₁) = r) : (dite c a b) = r := by simp [h₁, h₂]
-theorem dite_cond_eq_false' {α : Sort u} {c : Prop} {_ : Decidable c} {a : c → α} {b : ¬ c → α} {r : α} (h₁ : c = False) (h₂ : b (of_eq_false h₁) = r) : (dite c a b) = r := by simp [h₁, h₂]
-
-/-! Casts -/
-
-theorem eqRec_heq.{u_1, u_2} {α : Sort u_2} {a : α}
-        {motive : (x : α) → a = x → Sort u_1} (v : motive a (Eq.refl a)) {b : α} (h : a = b)
-        : HEq (@Eq.rec α a motive v b h) v := by
- subst h; rfl
-
-theorem eqRecOn_heq.{u_1, u_2} {α : Sort u_2} {a : α}
-        {motive : (x : α) → a = x → Sort u_1} {b : α} (h : a = b) (v : motive a (Eq.refl a))
-        : HEq (@Eq.recOn α a motive b h v) v := by
- subst h; rfl
-
-theorem eqNDRec_heq.{u_1, u_2} {α : Sort u_2} {a : α}
-        {motive : α → Sort u_1} (v : motive a) {b : α} (h : a = b)
-        : HEq (@Eq.ndrec α a motive v b h) v := by
- subst h; rfl
-
 end Lean.Grind

src/Init/Grind/Norm.lean

@@ -5,7 +5,6 @@ Authors: Leonardo de Moura
 -/
 prelude
 import Init.SimpLemmas
-import Init.PropLemmas
 import Init.Classical
 import Init.ByCases
 
@@ -41,17 +40,10 @@ attribute [grind_norm] not_true
 -- False
 attribute [grind_norm] not_false_eq_true
 
--- Remark: we disabled the following normalization rule because we want this information when implementing splitting heuristics
 -- Implication as a clause
-theorem imp_eq (p q : Prop) : (p → q) = (¬ p ∨ q) := by
+@[grind_norm↓] theorem imp_eq (p q : Prop) : (p → q) = (¬ p ∨ q) := by
   by_cases p <;> by_cases q <;> simp [*]
 
-@[grind_norm] theorem true_imp_eq (p : Prop) : (True → p) = p := by simp
-@[grind_norm] theorem false_imp_eq (p : Prop) : (False → p) = True := by simp
-@[grind_norm] theorem imp_true_eq (p : Prop) : (p → True) = True := by simp
-@[grind_norm] theorem imp_false_eq (p : Prop) : (p → False) = ¬p := by simp
-@[grind_norm] theorem imp_self_eq (p : Prop) : (p → p) = True := by simp
-
 -- And
 @[grind_norm↓] theorem not_and (p q : Prop) : (¬(p ∧ q)) = (¬p ∨ ¬q) := by
   by_cases p <;> by_cases q <;> simp [*]
@@ -66,19 +58,13 @@ attribute [grind_norm] ite_true ite_false
 @[grind_norm↓] theorem not_ite {_ : Decidable p} (q r : Prop) : (¬ite p q r) = ite p (¬q) (¬r) := by
   by_cases p <;> simp [*]
 
-@[grind_norm] theorem ite_true_false {_ : Decidable p} : (ite p True False) = p := by
-  by_cases p <;> simp
-
-@[grind_norm] theorem ite_false_true {_ : Decidable p} : (ite p False True) = ¬p := by
-  by_cases p <;> simp
-
 -- Forall
 @[grind_norm↓] theorem not_forall (p : α → Prop) : (¬∀ x, p x) = ∃ x, ¬p x := by simp
 attribute [grind_norm] forall_and
 
 -- Exists
 @[grind_norm↓] theorem not_exists (p : α → Prop) : (¬∃ x, p x) = ∀ x, ¬p x := by simp
-attribute [grind_norm] exists_const exists_or exists_prop exists_and_left exists_and_right
+attribute [grind_norm] exists_const exists_or
 
 -- Bool cond
 @[grind_norm] theorem cond_eq_ite (c : Bool) (a b : α) : cond c a b = ite c a b := by
@@ -121,7 +107,4 @@ attribute [grind_norm] Nat.le_zero_eq
 -- GT GE
 attribute [grind_norm] GT.gt GE.ge
 
--- Succ
-attribute [grind_norm] Nat.succ_eq_add_one
-
 end Lean.Grind

src/Init/Grind/Offset.lean

@@ -1,83 +0,0 @@
-/-
-Copyright (c) 2025 Amazon.com, Inc. or its affiliates. All Rights Reserved.
-Released under Apache 2.0 license as described in the file LICENSE.
-Authors: Leonardo de Moura
--/
-prelude
-import Init.Core
-import Init.Omega
-
-namespace Lean.Grind
-abbrev isLt (x y : Nat) : Bool := x < y
-abbrev isLE (x y : Nat) : Bool := x ≤ y
-
-/-! Theorems for transitivity. -/
-theorem Nat.le_ro (u w v k : Nat) : u ≤ w → w ≤ v + k → u ≤ v + k := by
-  omega
-theorem Nat.le_lo (u w v k : Nat) : u ≤ w → w + k ≤ v → u + k ≤ v := by
-  omega
-theorem Nat.lo_le (u w v k : Nat) : u + k ≤ w → w ≤ v → u + k ≤ v := by
-  omega
-theorem Nat.lo_lo (u w v k₁ k₂ : Nat) : u + k₁ ≤ w → w + k₂ ≤ v → u + (k₁ + k₂) ≤ v := by
-  omega
-theorem Nat.lo_ro_1 (u w v k₁ k₂ : Nat) : isLt k₂ k₁ = true → u + k₁ ≤ w → w ≤ v + k₂ → u + (k₁ - k₂) ≤ v := by
-  simp [isLt]; omega
-theorem Nat.lo_ro_2 (u w v k₁ k₂ : Nat) : u + k₁ ≤ w → w ≤ v + k₂ → u ≤ v + (k₂ - k₁) := by
-  omega
-theorem Nat.ro_le (u w v k : Nat) : u ≤ w + k → w ≤ v → u ≤ v + k := by
-  omega
-theorem Nat.ro_lo_1 (u w v k₁ k₂ : Nat) : u ≤ w + k₁ → w + k₂ ≤ v → u ≤ v + (k₁ - k₂) := by
-  omega
-theorem Nat.ro_lo_2 (u w v k₁ k₂ : Nat) : isLt k₁ k₂ = true → u ≤ w + k₁ → w + k₂ ≤ v → u + (k₂ - k₁) ≤ v := by
-  simp [isLt]; omega
-theorem Nat.ro_ro (u w v k₁ k₂ : Nat) : u ≤ w + k₁ → w ≤ v + k₂ → u ≤ v + (k₁ + k₂) := by
-  omega
-
-/-! Theorems for negating constraints. -/
-theorem Nat.of_le_eq_false (u v : Nat) : ((u ≤ v) = False) → v + 1 ≤ u := by
-  simp; omega
-theorem Nat.of_lo_eq_false_1 (u v : Nat) : ((u + 1 ≤ v) = False) → v ≤ u := by
-  simp; omega
-theorem Nat.of_lo_eq_false (u v k : Nat) : ((u + k ≤ v) = False) → v ≤ u + (k-1) := by
-  simp; omega
-theorem Nat.of_ro_eq_false (u v k : Nat) : ((u ≤ v + k) = False) → v + (k+1) ≤ u := by
-  simp; omega
-
-/-! Theorems for closing a goal. -/
-theorem Nat.unsat_le_lo (u v k : Nat) : isLt 0 k = true → u ≤ v → v + k ≤ u → False := by
-  simp [isLt]; omega
-theorem Nat.unsat_lo_lo (u v k₁ k₂ : Nat) : isLt 0 (k₁+k₂) = true → u + k₁ ≤ v → v + k₂ ≤ u → False := by
-  simp [isLt]; omega
-theorem Nat.unsat_lo_ro (u v k₁ k₂ : Nat) : isLt k₂ k₁ = true → u + k₁ ≤ v → v ≤ u + k₂ → False := by
-  simp [isLt]; omega
-
-/-! Theorems for propagating constraints to `True` -/
-theorem Nat.lo_eq_true_of_lo (u v k₁ k₂ : Nat) : isLE k₂ k₁ = true → u + k₁ ≤ v → (u + k₂ ≤ v) = True :=
-  by simp [isLt]; omega
-theorem Nat.le_eq_true_of_lo (u v k : Nat) : u + k ≤ v → (u ≤ v) = True :=
-  by simp; omega
-theorem Nat.le_eq_true_of_le (u v : Nat) : u ≤ v → (u ≤ v) = True :=
-  by simp
-theorem Nat.ro_eq_true_of_lo (u v k₁ k₂ : Nat) : u + k₁ ≤ v → (u ≤ v + k₂) = True :=
-  by simp; omega
-theorem Nat.ro_eq_true_of_le (u v k : Nat) : u ≤ v → (u ≤ v + k) = True :=
-  by simp; omega
-theorem Nat.ro_eq_true_of_ro (u v k₁ k₂ : Nat) : isLE k₁ k₂ = true → u ≤ v + k₁ → (u ≤ v + k₂) = True :=
-  by simp [isLE]; omega
-
-/-!
-Theorems for propagating constraints to `False`.
-They are variants of the theorems for closing a goal.
--/
-theorem Nat.lo_eq_false_of_le (u v k : Nat) : isLt 0 k = true → u ≤ v → (v + k ≤ u) = False := by
- simp [isLt]; omega
-theorem Nat.le_eq_false_of_lo (u v k : Nat) : isLt 0 k = true → u + k ≤ v → (v ≤ u) = False := by
- simp [isLt]; omega
-theorem Nat.lo_eq_false_of_lo (u v k₁ k₂ : Nat) : isLt 0 (k₁+k₂) = true → u + k₁ ≤ v → (v + k₂ ≤ u) = False := by
-  simp [isLt]; omega
-theorem Nat.ro_eq_false_of_lo (u v k₁ k₂ : Nat) : isLt k₂ k₁ = true → u + k₁ ≤ v → (v ≤ u + k₂) = False := by
-  simp [isLt]; omega
-theorem Nat.lo_eq_false_of_ro (u v k₁ k₂ : Nat) : isLt k₁ k₂ = true → u ≤ v + k₁ → (v + k₂ ≤ u) = False := by
-  simp [isLt]; omega
-
-end Lean.Grind

src/Init/Grind/PP.lean

@@ -1,30 +0,0 @@
-/-
-Copyright (c) 2024 Amazon.com, Inc. or its affiliates. All Rights Reserved.
-Released under Apache 2.0 license as described in the file LICENSE.
-Authors: Leonardo de Moura
--/
-prelude
-import Init.NotationExtra
-
-namespace Lean.Grind
-/-!
-This is a hackish module for hovering node information in the `grind` tactic state.
--/
-
-inductive NodeDef where
-  | unit
-
-set_option linter.unusedVariables false in
-def node_def (_ : Nat) {α : Sort u} {a : α} : NodeDef := .unit
-
-@[app_unexpander node_def]
-def nodeDefUnexpander : PrettyPrinter.Unexpander := fun stx => do
-  match stx with
-  | `($_ $id:num) => return mkIdent <| Name.mkSimple $ "#" ++ toString id.getNat
-  | _ => throw ()
-
-@[app_unexpander NodeDef]
-def NodeDefUnexpander : PrettyPrinter.Unexpander := fun _ => do
-  return mkIdent <| Name.mkSimple "NodeDef"
-
-end Lean.Grind

src/Init/Grind/Tactics.lean

@@ -6,27 +6,20 @@ Authors: Leonardo de Moura
 prelude
 import Init.Tactics
 
-namespace Lean.Parser.Attr
-
-syntax grindEq     := "="
-syntax grindEqBoth := atomic("_" "=" "_")
-syntax grindEqRhs  := atomic("=" "_")
-syntax grindBwd    := "←"
-syntax grindFwd    := "→"
-
-syntax (name := grind) "grind" (grindEqBoth <|> grindEqRhs <|> grindEq <|> grindBwd <|> grindFwd)? : attr
-
-end Lean.Parser.Attr
-
 namespace Lean.Grind
 /--
 The configuration for `grind`.
-Passed to `grind` using, for example, the `grind (config := { matchEqs := true })` syntax.
+Passed to `grind` using, for example, the `grind (config := { eager := true })` syntax.
 -/
 structure Config where
-  /-- Maximum number of case-splits in a proof search branch. It does not include splits performed during normalization. -/
-  splits : Nat := 8
-  /-- Maximum number of E-matching (aka heuristic theorem instantiation) rounds before each case split. -/
+  /-- When `eager` is true (default: `false`), `grind` eagerly splits `if-then-else` and `match` expressions during internalization. -/
+  eager : Bool := false
+  /-- Maximum number of branches (i.e., case-splits) in the proof search tree. -/
+  splits : Nat := 100
+  /--
+  Maximum number of E-matching (aka heuristic theorem instantiation)
+  in a proof search tree branch.
+  -/
   ematch : Nat := 5
   /--
   Maximum term generation.
@@ -35,16 +28,6 @@ structure Config where
   gen : Nat := 5
   /-- Maximum number of theorem instances generated using E-matching in a proof search tree branch. -/
   instances : Nat := 1000
-  /-- If `matchEqs` is `true`, `grind` uses `match`-equations as E-matching theorems. -/
-  matchEqs : Bool := true
-  /-- If `splitMatch` is `true`, `grind` performs case-splitting on `match`-expressions during the search. -/
-  splitMatch : Bool := true
-  /-- If `splitIte` is `true`, `grind` performs case-splitting on `if-then-else` expressions during the search. -/
-  splitIte : Bool := true
-  /--
-  If `splitIndPred` is `true`, `grind` performs case-splitting on inductive predicates.
-  Otherwise, it performs case-splitting only on types marked with `[grind_split]` attribute. -/
-  splitIndPred : Bool := true
   deriving Inhabited, BEq
 
 end Lean.Grind

src/Init/Grind/Util.lean

@@ -9,26 +9,11 @@ import Init.Core
 namespace Lean.Grind
 
 /-- A helper gadget for annotating nested proofs in goals. -/
-def nestedProof (p : Prop) {h : p} : p := h
+def nestedProof (p : Prop) (h : p) : p := h
 
-/--
-Gadget for marking terms that should not be normalized by `grind`s simplifier.
-`grind` uses a simproc to implement this feature.
-We use it when adding instances of `match`-equations to prevent them from being simplified to true.
--/
-def doNotSimp {α : Sort u} (a : α) : α := a
+set_option pp.proofs true
 
-/-- Gadget for representing offsets `t+k` in patterns. -/
-def offset (a b : Nat) : Nat := a + b
-
-/--
-Gadget for annotating the equalities in `match`-equations conclusions.
-`_origin` is the term used to instantiate the `match`-equation using E-matching.
-When `EqMatch a b origin` is `True`, we mark `origin` as a resolved case-split.
--/
-def EqMatch (a b : α) {_origin : α} : Prop := a = b
-
-theorem nestedProof_congr (p q : Prop) (h : p = q) (hp : p) (hq : q) : HEq (@nestedProof p hp) (@nestedProof q hq) := by
+theorem nestedProof_congr (p q : Prop) (h : p = q) (hp : p) (hq : q) : HEq (nestedProof p hp) (nestedProof q hq) := by
   subst h; apply HEq.refl
 
 end Lean.Grind

src/Init/Prelude.lean

@@ -4170,16 +4170,6 @@ def withRef [Monad m] [MonadRef m] {α} (ref : Syntax) (x : m α) : m α :=
   let ref := replaceRef ref oldRef
   MonadRef.withRef ref x
 
-/--
-If `ref? = some ref`, run `x : m α` with a modified value for the `ref` by calling `withRef`.
-Otherwise, run `x` directly.
--/
-@[always_inline, inline]
-def withRef? [Monad m] [MonadRef m] {α} (ref? : Option Syntax) (x : m α) : m α :=
-  match ref? with
-  | some ref => withRef ref x
-  | _        => x
-
 /-- A monad that supports syntax quotations. Syntax quotations (in term
     position) are monadic values that when executed retrieve the current "macro
     scope" from the monad and apply it to every identifier they introduce

src/Init/Tactics.lean

@@ -818,7 +818,7 @@ syntax inductionAlt  := ppDedent(ppLine) inductionAltLHS+ " => " (hole <|> synth
 After `with`, there is an optional tactic that runs on all branches, and
 then a list of alternatives.
 -/
-syntax inductionAlts := " with" (ppSpace colGt tactic)? withPosition((colGe inductionAlt)*)
+syntax inductionAlts := " with" (ppSpace colGt tactic)? withPosition((colGe inductionAlt)+)
 
 /--
 Assuming `x` is a variable in the local context with an inductive type,

src/Lean/AddDecl.lean

@@ -21,6 +21,11 @@ def Environment.addDecl (env : Environment) (opts : Options) (decl : Declaration
   else
     addDeclCore env (Core.getMaxHeartbeats opts).toUSize decl cancelTk?
 
+def Environment.addAndCompile (env : Environment) (opts : Options) (decl : Declaration)
+    (cancelTk? : Option IO.CancelToken := none) : Except KernelException Environment := do
+  let env ← addDecl env opts decl cancelTk?
+  compileDecl env opts decl
+
 def addDecl (decl : Declaration) : CoreM Unit := do
   profileitM Exception "type checking" (← getOptions) do
     withTraceNode `Kernel (fun _ => return m!"typechecking declaration") do

src/Lean/Compiler/InitAttr.lean

@@ -144,7 +144,11 @@ def declareBuiltin (forDecl : Name) (value : Expr) : CoreM Unit := do
   let type := mkApp (mkConst `IO) (mkConst `Unit)
   let decl := Declaration.defnDecl { name, levelParams := [], type, value, hints := ReducibilityHints.opaque,
                                      safety := DefinitionSafety.safe }
-  addAndCompile decl
-  IO.ofExcept (setBuiltinInitAttr (← getEnv) name) >>= setEnv
+  match (← getEnv).addAndCompile {} decl with
+  -- TODO: pretty print error
+  | Except.error e => do
+    let msg ← (e.toMessageData {}).toString
+    throwError "failed to emit registration code for builtin '{forDecl}': {msg}"
+  | Except.ok env  => IO.ofExcept (setBuiltinInitAttr env name) >>= setEnv
 
 end Lean

src/Lean/Compiler/Old.lean

@@ -53,3 +53,18 @@ def isUnsafeRecName? : Name → Option Name
   | _ => none
 
 end Compiler
+
+namespace Environment
+
+/--
+Compile the given block of mutual declarations.
+Assumes the declarations have already been added to the environment using `addDecl`.
+-/
+@[extern "lean_compile_decls"]
+opaque compileDecls (env : Environment) (opt : @& Options) (decls : @& List Name) : Except KernelException Environment
+
+/-- Compile the given declaration, it assumes the declaration has already been added to the environment using `addDecl`. -/
+def compileDecl (env : Environment) (opt : @& Options) (decl : @& Declaration) : Except KernelException Environment :=
+  compileDecls env opt (Compiler.getDeclNamesForCodeGen decl)
+
+end Environment

src/Lean/CoreM.lean

@@ -514,16 +514,13 @@ register_builtin_option compiler.enableNew : Bool := {
 @[extern "lean_lcnf_compile_decls"]
 opaque compileDeclsNew (declNames : List Name) : CoreM Unit
 
-@[extern "lean_compile_decls"]
-opaque compileDeclsOld (env : Environment) (opt : @& Options) (decls : @& List Name) : Except KernelException Environment
-
 def compileDecl (decl : Declaration) : CoreM Unit := do
   let opts ← getOptions
   let decls := Compiler.getDeclNamesForCodeGen decl
   if compiler.enableNew.get opts then
     compileDeclsNew decls
   let res ← withTraceNode `compiler (fun _ => return m!"compiling old: {decls}") do
-    return compileDeclsOld (← getEnv) opts decls
+    return (← getEnv).compileDecl opts decl
   match res with
   | Except.ok env => setEnv env
   | Except.error (KernelException.other msg) =>
@@ -536,7 +533,7 @@ def compileDecls (decls : List Name) : CoreM Unit := do
   let opts ← getOptions
   if compiler.enableNew.get opts then
     compileDeclsNew decls
-  match compileDeclsOld (← getEnv) opts decls with
+  match (← getEnv).compileDecls opts decls with
   | Except.ok env   => setEnv env
   | Except.error (KernelException.other msg) =>
     throwError msg

src/Lean/Data/AssocList.lean

@@ -24,7 +24,7 @@ abbrev empty : AssocList α β :=
 
 instance : EmptyCollection (AssocList α β) := ⟨empty⟩
 
-abbrev insertNew (m : AssocList α β) (k : α) (v : β) : AssocList α β :=
+abbrev insert (m : AssocList α β) (k : α) (v : β) : AssocList α β :=
   m.cons k v
 
 def isEmpty : AssocList α β → Bool
@@ -77,12 +77,6 @@ def replace [BEq α] (a : α) (b : β) : AssocList α β → AssocList α β
     | true  => cons a b es
     | false => cons k v (replace a b es)
 
-def insert [BEq α] (m : AssocList α β) (k : α) (v : β) : AssocList α β :=
-  if m.contains k then
-    m.replace k v
-  else
-    m.insertNew k v
-
 def erase [BEq α] (a : α) : AssocList α β → AssocList α β
   | nil         => nil
   | cons k v es => match k == a with

src/Lean/Data/Json/Printer.lean

@@ -11,22 +11,6 @@ import Init.Data.List.Impl
 namespace Lean
 namespace Json
 
-set_option maxRecDepth 1024 in
-/--
-This table contains for each UTF-8 byte whether we need to escape a string that contains it.
--/
-private def escapeTable : { xs : ByteArray // xs.size = 256 } :=
-  ⟨ByteArray.mk #[
-    1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1, 1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,
-    0,0,1,0,0,0,0,0,0,0,0,0,0,0,0,1, 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,
-    0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0, 0,0,0,0,0,0,0,0,0,0,0,0,1,0,0,0,
-    0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0, 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,
-    1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1, 1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,
-    1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1, 1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,
-    1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1, 1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,
-    1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1, 1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1
-  ], by rfl⟩
-
 private def escapeAux (acc : String) (c : Char) : String :=
   -- escape ", \, \n and \r, keep all other characters ≥ 0x20 and render characters < 0x20 with \u
   if c = '"' then -- hack to prevent emacs from regarding the rest of the file as a string: "
@@ -55,27 +39,8 @@ private def escapeAux (acc : String) (c : Char) : String :=
     let d4 := Nat.digitChar (n % 16)
     acc ++ "\\u" |>.push d1 |>.push d2 |>.push d3 |>.push d4
 
-private def needEscape (s : String) : Bool :=
-  go s 0
-where
-  go (s : String) (i : Nat) : Bool :=
-    if h : i < s.utf8ByteSize then
-      let byte := s.getUtf8Byte i h
-      have h1 : byte.toNat < 256 := UInt8.toNat_lt_size byte
-      have h2 : escapeTable.val.size = 256 := escapeTable.property
-      if escapeTable.val.get byte.toNat (Nat.lt_of_lt_of_eq h1 h2.symm) == 0 then
-        go s (i + 1)
-      else
-        true
-    else
-      false
-
 def escape (s : String) (acc : String := "") : String :=
-  -- If we don't have any characters that need to be escaped we can just append right away.
-  if needEscape s then
-    s.foldl escapeAux acc
-  else
-    acc ++ s
+  s.foldl escapeAux acc
 
 def renderString (s : String) (acc : String := "") : String :=
   let acc := acc ++ "\""

src/Lean/Data/Lsp.lean

@@ -6,7 +6,6 @@ Authors: Marc Huisinga, Wojciech Nawrocki
 -/
 prelude
 import Lean.Data.Lsp.Basic
-import Lean.Data.Lsp.CancelParams
 import Lean.Data.Lsp.Capabilities
 import Lean.Data.Lsp.Client
 import Lean.Data.Lsp.Communication

src/Lean/Data/Lsp/Basic.lean

@@ -6,6 +6,7 @@ Authors: Marc Huisinga, Wojciech Nawrocki
 -/
 prelude
 import Lean.Data.Json
+import Lean.Data.JsonRpc
 
 /-! Defines most of the 'Basic Structures' in the LSP specification
 (https://microsoft.github.io/language-server-protocol/specifications/specification-current/),
@@ -18,6 +19,10 @@ namespace Lsp
 
 open Json
 
+structure CancelParams where
+  id : JsonRpc.RequestID
+  deriving Inhabited, BEq, ToJson, FromJson
+
 abbrev DocumentUri := String
 
 /-- We adopt the convention that zero-based UTF-16 positions as sent by LSP clients

src/Lean/Data/Lsp/CancelParams.lean

@@ -1,25 +0,0 @@
-/-
-Copyright (c) 2020 Marc Huisinga. All rights reserved.
-Released under Apache 2.0 license as described in the file LICENSE.
-
-Authors: Marc Huisinga, Wojciech Nawrocki
--/
-prelude
-import Lean.Data.JsonRpc
-
-/-! # Defines `Lean.Lsp.CancelParams`.
-
-This is separate from `Lean.Data.Lsp.Basic` to reduce transitive dependencies.
--/
-
-namespace Lean
-namespace Lsp
-
-open Json
-
-structure CancelParams where
-  id : JsonRpc.RequestID
-  deriving Inhabited, BEq, ToJson, FromJson
-
-end Lsp
-end Lean

src/Lean/Data/Lsp/Utf16.lean

@@ -6,6 +6,7 @@ Authors: Marc Huisinga, Wojciech Nawrocki
 -/
 prelude
 import Init.Data.String
+import Init.Data.Array
 import Lean.Data.Lsp.Basic
 import Lean.Data.Position
 import Lean.DeclarationRange

src/Lean/Elab/App.lean

@@ -1474,7 +1474,7 @@ where
     | field::fields, false => .fieldName field field.getId.getString! none fIdent :: toLVals fields false
 
 /-- Resolve `(.$id:ident)` using the expected type to infer namespace. -/
-private partial def resolveDotName (id : Syntax) (expectedType? : Option Expr) : TermElabM Expr := do
+private partial def resolveDotName (id : Syntax) (expectedType? : Option Expr) : TermElabM Name := do
   tryPostponeIfNoneOrMVar expectedType?
   let some expectedType := expectedType?
     | throwError "invalid dotted identifier notation, expected type must be known"
@@ -1489,7 +1489,7 @@ where
         withForallBody body k
       else
         k body
-  go (resultType : Expr) (expectedType : Expr) (previousExceptions : Array Exception) : TermElabM Expr := do
+  go (resultType : Expr) (expectedType : Expr) (previousExceptions : Array Exception) : TermElabM Name := do
     let resultType ← instantiateMVars resultType
     let resultTypeFn := resultType.cleanupAnnotations.getAppFn
     try
@@ -1497,12 +1497,9 @@ where
       let .const declName .. := resultTypeFn.cleanupAnnotations
         | throwError "invalid dotted identifier notation, expected type is not of the form (... → C ...) where C is a constant{indentExpr expectedType}"
       let idNew := declName ++ id.getId.eraseMacroScopes
-      if (← getEnv).contains idNew then
-        mkConst idNew
-      else if let some (fvar, []) ← resolveLocalName idNew then
-        return fvar
-      else
+      unless (← getEnv).contains idNew do
         throwError "invalid dotted identifier notation, unknown identifier `{idNew}` from expected type{indentExpr expectedType}"
+      return idNew
     catch
       | ex@(.error ..) =>
         match (← unfoldDefinition? resultType) with
@@ -1551,7 +1548,7 @@ private partial def elabAppFn (f : Syntax) (lvals : List LVal) (namedArgs : Arra
     | `(_)       => throwError "placeholders '_' cannot be used where a function is expected"
     | `(.$id:ident) =>
         addCompletionInfo <| CompletionInfo.dotId f id.getId (← getLCtx) expectedType?
-        let fConst ← resolveDotName id expectedType?
+        let fConst ← mkConst (← resolveDotName id expectedType?)
         let s ← observing do
           -- Use (force := true) because we want to record the result of .ident resolution even in patterns
           let fConst ← addTermInfo f fConst expectedType? (force := true)

src/Lean/Elab/Import.lean

@@ -5,7 +5,7 @@ Authors: Leonardo de Moura, Sebastian Ullrich
 -/
 prelude
 import Lean.Parser.Module
-import Lean.Util.Paths
+import Lean.Data.Json
 
 namespace Lean.Elab
 
@@ -42,12 +42,4 @@ def printImports (input : String) (fileName : Option String) : IO Unit := do
     let fname ← findOLean dep.module
     IO.println fname
 
-@[export lean_print_import_srcs]
-def printImportSrcs (input : String) (fileName : Option String) : IO Unit := do
-  let sp ← initSrcSearchPath
-  let (deps, _, _) ← parseImports input fileName
-  for dep in deps do
-    let fname ← findLean sp dep.module
-    IO.println fname
-
 end Lean.Elab

src/Lean/Elab/Tactic/BuiltinTactic.lean

@@ -362,9 +362,9 @@ partial def evalChoiceAux (tactics : Array Syntax) (i : Nat) : TacticM Unit :=
   | `(tactic| intro $h:term $hs:term*) => evalTactic (← `(tactic| intro $h:term; intro $hs:term*))
   | _ => throwUnsupportedSyntax
 where
-  introStep (ref? : Option Syntax) (n : Name) (typeStx? : Option Syntax := none) : TacticM Unit := do
+  introStep (ref : Option Syntax) (n : Name) (typeStx? : Option Syntax := none) : TacticM Unit := do
     let fvarId ← liftMetaTacticAux fun mvarId => do
-      let (fvarId, mvarId) ← withRef? ref? <| mvarId.intro n
+      let (fvarId, mvarId) ← mvarId.intro n
       pure (fvarId, [mvarId])
     if let some typeStx := typeStx? then
       withMainContext do
@@ -374,9 +374,9 @@ where
         unless (← isDefEqGuarded type fvarType) do
           throwError "type mismatch at `intro {fvar}`{← mkHasTypeButIsExpectedMsg fvarType type}"
         liftMetaTactic fun mvarId => return [← mvarId.replaceLocalDeclDefEq fvarId type]
-    if let some ref := ref? then
+    if let some stx := ref then
       withMainContext do
-        Term.addLocalVarInfo ref (mkFVar fvarId)
+        Term.addLocalVarInfo stx (mkFVar fvarId)
 
 @[builtin_tactic Lean.Parser.Tactic.introMatch] def evalIntroMatch : Tactic := fun stx => do
   let matchAlts := stx[1]

src/Lean/Elab/Tactic/Classical.lean

@@ -24,8 +24,11 @@ def classical [Monad m] [MonadEnv m] [MonadFinally m] [MonadLiftT MetaM m] (t :
   finally
     modifyEnv Meta.instanceExtension.popScope
 
-@[builtin_tactic Lean.Parser.Tactic.classical, builtin_incremental]
-def evalClassical : Tactic := fun stx =>
-  classical <| Term.withNarrowedArgTacticReuse (argIdx := 1) Elab.Tactic.evalTactic stx
+@[builtin_tactic Lean.Parser.Tactic.classical]
+def evalClassical : Tactic := fun stx => do
+  match stx with
+  | `(tactic| classical $tacs:tacticSeq) =>
+     classical <| Elab.Tactic.evalTactic tacs
+  | _ => throwUnsupportedSyntax
 
 end Lean.Elab.Tactic

src/Lean/Elab/Tactic/Conv/Simp.lean

@@ -7,10 +7,9 @@ prelude
 import Lean.Elab.Tactic.Simp
 import Lean.Elab.Tactic.Split
 import Lean.Elab.Tactic.Conv.Basic
-import Lean.Elab.Tactic.SimpTrace
 
 namespace Lean.Elab.Tactic.Conv
-open Meta Tactic TryThis
+open Meta
 
 def applySimpResult (result : Simp.Result) : TacticM Unit := do
   if result.proof?.isNone then
@@ -24,19 +23,6 @@ def applySimpResult (result : Simp.Result) : TacticM Unit := do
   let (result, _) ← dischargeWrapper.with fun d? => simp lhs ctx (simprocs := simprocs) (discharge? := d?)
   applySimpResult result
 
-@[builtin_tactic Lean.Parser.Tactic.Conv.simpTrace] def evalSimpTrace : Tactic := fun stx => withMainContext do
-  match stx with
-  | `(conv| simp?%$tk $cfg:optConfig $(discharger)? $[only%$o]? $[[$args,*]]?) => do
-    let stx ← `(tactic| simp%$tk $cfg:optConfig $[$discharger]? $[only%$o]? $[[$args,*]]?)
-    let { ctx, simprocs, dischargeWrapper, .. } ← mkSimpContext stx (eraseLocal := false)
-    let lhs ← getLhs
-    let (result, stats) ← dischargeWrapper.with fun d? =>
-      simp lhs ctx (simprocs := simprocs) (discharge? := d?)
-    applySimpResult result
-    let stx ← mkSimpCallStx stx stats.usedTheorems
-    addSuggestion tk stx (origSpan? := ← getRef)
-  | _ => throwUnsupportedSyntax
-
 @[builtin_tactic Lean.Parser.Tactic.Conv.simpMatch] def evalSimpMatch : Tactic := fun _ => withMainContext do
   applySimpResult (← Split.simpMatch (← getLhs))
 
@@ -44,15 +30,4 @@ def applySimpResult (result : Simp.Result) : TacticM Unit := do
   let { ctx, .. } ← mkSimpContext stx (eraseLocal := false) (kind := .dsimp)
   changeLhs (← Lean.Meta.dsimp (← getLhs) ctx).1
 
-@[builtin_tactic Lean.Parser.Tactic.Conv.dsimpTrace] def evalDSimpTrace : Tactic := fun stx => withMainContext do
-  match stx with
-  | `(conv| dsimp?%$tk $cfg:optConfig $[only%$o]? $[[$args,*]]?) =>
-    let stx ← `(tactic| dsimp%$tk $cfg:optConfig $[only%$o]? $[[$args,*]]?)
-    let { ctx, .. } ← mkSimpContext stx (eraseLocal := false) (kind := .dsimp)
-    let (result, stats) ← Lean.Meta.dsimp (← getLhs) ctx
-    changeLhs result
-    let stx ← mkSimpCallStx stx stats.usedTheorems
-    addSuggestion tk stx (origSpan? := ← getRef)
-  | _ => throwUnsupportedSyntax
-
 end Lean.Elab.Tactic.Conv

src/Lean/Elab/Tactic/Grind.lean

@@ -26,18 +26,16 @@ def elabGrindPattern : CommandElab := fun stx => do
       let info ← getConstInfo declName
       forallTelescope info.type fun xs _ => do
         let patterns ← terms.getElems.mapM fun term => do
-          let pattern ← elabTerm term none
-          synthesizeSyntheticMVarsUsingDefault
-          let pattern ← instantiateMVars pattern
-          let pattern ← Grind.preprocessPattern pattern
+          let pattern ← instantiateMVars (← elabTerm term none)
+          let pattern ← Grind.unfoldReducible pattern
           return pattern.abstract xs
         Grind.addEMatchTheorem declName xs.size patterns.toList
   | _ => throwUnsupportedSyntax
 
 def grind (mvarId : MVarId) (config : Grind.Config) (mainDeclName : Name) (fallback : Grind.Fallback) : MetaM Unit := do
-  let goals ← Grind.main mvarId config mainDeclName fallback
-  unless goals.isEmpty do
-    throwError "`grind` failed\n{← Grind.goalsToMessageData goals}"
+  let mvarIds ← Grind.main mvarId config mainDeclName fallback
+  unless mvarIds.isEmpty do
+    throwError "`grind` failed\n{goalsToMessageData mvarIds}"
 
 private def elabFallback (fallback? : Option Term) : TermElabM (Grind.GoalM Unit) := do
   let some fallback := fallback? | return (pure ())

src/Lean/Elab/Tactic/Induction.lean

@@ -258,11 +258,11 @@ private def saveAltVarsInfo (altMVarId : MVarId) (altStx : Syntax) (fvarIds : Ar
           i := i + 1
 
 open Language in
-def evalAlts (elimInfo : ElimInfo) (alts : Array Alt) (optPreTac : Syntax) (altStxs? : Option (Array Syntax))
+def evalAlts (elimInfo : ElimInfo) (alts : Array Alt) (optPreTac : Syntax) (altStxs : Array Syntax)
     (initialInfo : Info)
     (numEqs : Nat := 0) (numGeneralized : Nat := 0) (toClear : Array FVarId := #[])
     (toTag : Array (Ident × FVarId) := #[]) : TacticM Unit := do
-  let hasAlts := altStxs?.isSome
+  let hasAlts := altStxs.size > 0
   if hasAlts then
     -- default to initial state outside of alts
     -- HACK: because this node has the same span as the original tactic,
@@ -274,7 +274,9 @@ def evalAlts (elimInfo : ElimInfo) (alts : Array Alt) (optPreTac : Syntax) (altS
 where
   -- continuation in the correct info context
   goWithInfo := do
-    if let some altStxs := altStxs? then
+    let hasAlts := altStxs.size > 0
+
+    if hasAlts then
       if let some tacSnap := (← readThe Term.Context).tacSnap? then
         -- incrementality: create a new promise for each alternative, resolve current snapshot to
         -- them, eventually put each of them back in `Context.tacSnap?` in `applyAltStx`
@@ -307,8 +309,7 @@ where
 
   -- continuation in the correct incrementality context
   goWithIncremental (tacSnaps : Array (SnapshotBundle TacticParsedSnapshot)) := do
-    let hasAlts := altStxs?.isSome
-    let altStxs := altStxs?.getD #[]
+    let hasAlts := altStxs.size > 0
     let mut alts := alts
 
     -- initial sanity checks: named cases should be known, wildcards should be last
@@ -342,12 +343,12 @@ where
       let altName := getAltName altStx
       if let some i := alts.findFinIdx? (·.1 == altName) then
         -- cover named alternative
-        applyAltStx tacSnaps altStxs altStxIdx altStx alts[i]
+        applyAltStx tacSnaps altStxIdx altStx alts[i]
         alts := alts.eraseIdx i
       else if !alts.isEmpty && isWildcard altStx then
         -- cover all alternatives
         for alt in alts do
-          applyAltStx tacSnaps altStxs altStxIdx altStx alt
+          applyAltStx tacSnaps altStxIdx altStx alt
         alts := #[]
       else
         throwErrorAt altStx "unused alternative '{altName}'"
@@ -378,7 +379,7 @@ where
         altMVarIds.forM fun mvarId => admitGoal mvarId
 
   /-- Applies syntactic alternative to alternative goal. -/
-  applyAltStx tacSnaps altStxs altStxIdx altStx alt := withRef altStx do
+  applyAltStx tacSnaps altStxIdx altStx alt := withRef altStx do
     let { name := altName, info, mvarId := altMVarId } := alt
     -- also checks for unknown alternatives
     let numFields ← getAltNumFields elimInfo altName
@@ -475,7 +476,7 @@ private def generalizeVars (mvarId : MVarId) (stx : Syntax) (targets : Array Exp
 /--
 Given `inductionAlts` of the form
 ```
-syntax inductionAlts := "with " (tactic)? withPosition( (colGe inductionAlt)*)
+syntax inductionAlts := "with " (tactic)? withPosition( (colGe inductionAlt)+)
 ```
 Return an array containing its alternatives.
 -/
@@ -485,30 +486,21 @@ private def getAltsOfInductionAlts (inductionAlts : Syntax) : Array Syntax :=
 /--
 Given `inductionAlts` of the form
 ```
-syntax inductionAlts := "with " (tactic)? withPosition( (colGe inductionAlt)*)
+syntax inductionAlts := "with " (tactic)? withPosition( (colGe inductionAlt)+)
 ```
-runs `cont (some alts)` where `alts` is an array containing all `inductionAlt`s while disabling incremental
-reuse if any other syntax changed. If there's no `with` clause, then runs `cont none`.
+runs `cont alts` where `alts` is an array containing all `inductionAlt`s while disabling incremental
+reuse if any other syntax changed.
 -/
 private def withAltsOfOptInductionAlts (optInductionAlts : Syntax)
-    (cont : Option (Array Syntax) → TacticM α) : TacticM α :=
+    (cont : Array Syntax → TacticM α) : TacticM α :=
   Term.withNarrowedTacticReuse (stx := optInductionAlts) (fun optInductionAlts =>
     if optInductionAlts.isNone then
       -- if there are no alternatives, what to compare is irrelevant as there will be no reuse
       (mkNullNode #[], mkNullNode #[])
     else
-      -- if there are no alts, then use the `with` token for `inner` for a ref for messages
-      let altStxs := optInductionAlts[0].getArg 2
-      let inner := if altStxs.getNumArgs > 0 then altStxs else optInductionAlts[0][0]
       -- `with` and tactic applied to all branches must be unchanged for reuse
-      (mkNullNode optInductionAlts[0].getArgs[:2], inner))
-    (fun alts? =>
-      if optInductionAlts.isNone then      -- no `with` clause
-        cont none
-      else if alts?.isOfKind nullKind then -- has alts
-        cont (some alts?.getArgs)
-      else                                 -- has `with` clause, but no alts
-        cont (some #[]))
+      (mkNullNode optInductionAlts[0].getArgs[:2], optInductionAlts[0].getArg 2))
+    (fun alts => cont alts.getArgs)
 
 private def getOptPreTacOfOptInductionAlts (optInductionAlts : Syntax) : Syntax :=
   if optInductionAlts.isNone then mkNullNode else optInductionAlts[0][1]
@@ -526,7 +518,7 @@ private def expandMultiAlt? (alt : Syntax) : Option (Array Syntax) := Id.run do
 /--
 Given `inductionAlts` of the form
 ```
-syntax inductionAlts := "with " (tactic)? withPosition( (colGe inductionAlt)*)
+syntax inductionAlts := "with " (tactic)? withPosition( (colGe inductionAlt)+)
 ```
 Return `some inductionAlts'` if one of the alternatives have multiple LHSs, in the new `inductionAlts'`
 all alternatives have a single LHS.
@@ -708,10 +700,10 @@ def evalInduction : Tactic := fun stx =>
         -- unchanged
         -- everything up to the alternatives must be unchanged for reuse
         Term.withNarrowedArgTacticReuse (stx := stx) (argIdx := 4) fun optInductionAlts => do
-        withAltsOfOptInductionAlts optInductionAlts fun alts? => do
+        withAltsOfOptInductionAlts optInductionAlts fun alts => do
           let optPreTac := getOptPreTacOfOptInductionAlts optInductionAlts
           mvarId.assign result.elimApp
-          ElimApp.evalAlts elimInfo result.alts optPreTac alts? initInfo (numGeneralized := n) (toClear := targetFVarIds)
+          ElimApp.evalAlts elimInfo result.alts optPreTac alts initInfo (numGeneralized := n) (toClear := targetFVarIds)
           appendGoals result.others.toList
 where
   checkTargets (targets : Array Expr) : MetaM Unit := do

src/Lean/Elab/Tactic/Omega/Frontend.lean

@@ -680,7 +680,7 @@ def omegaTactic (cfg : OmegaConfig) : TacticM Unit := do
 
 /-- The `omega` tactic, for resolving integer and natural linear arithmetic problems. This
 `TacticM Unit` frontend with default configuration can be used as an Aesop rule, for example via
-the tactic call `aesop (add 50% tactic Lean.Elab.Tactic.Omega.omegaDefault)`. -/
+the tactic call `aesop (add 50% tactic Lean.Omega.omegaDefault)`. -/
 def omegaDefault : TacticM Unit := omegaTactic {}
 
 @[builtin_tactic Lean.Parser.Tactic.omega]

src/Lean/Elab/Tactic/RCases.lean

@@ -507,7 +507,7 @@ partial def rintroCore (g : MVarId) (fs : FVarSubst) (clears : Array FVarId) (a
   match pat with
   | `(rintroPat| $pat:rcasesPat) =>
     let pat := (← RCasesPatt.parse pat).typed? ref ty?
-    let (v, g) ← withRef pat.ref <| g.intro (pat.name?.getD `_)
+    let (v, g) ← g.intro (pat.name?.getD `_)
     rcasesCore g fs clears (.fvar v) a pat cont
   | `(rintroPat| ($(pats)* $[: $ty?']?)) =>
     let ref := if pats.size == 1 then pat.raw else .missing

src/Lean/Linter/MissingDocs.lean

@@ -4,7 +4,6 @@ Released under Apache 2.0 license as described in the file LICENSE.
 Authors: Mario Carneiro
 -/
 prelude
-import Lean.Parser.Syntax
 import Lean.Meta.Tactic.Simp.RegisterCommand
 import Lean.Elab.Command
 import Lean.Elab.SetOption

src/Lean/Meta/AppBuilder.lean

@@ -11,14 +11,14 @@ import Lean.Meta.DecLevel
 
 namespace Lean.Meta
 
-/-- Returns `id e` -/
+/-- Return `id e` -/
 def mkId (e : Expr) : MetaM Expr := do
   let type ← inferType e
   let u    ← getLevel type
   return mkApp2 (mkConst ``id [u]) type e
 
 /--
-  Given `e` s.t. `inferType e` is definitionally equal to `expectedType`, returns
+  Given `e` s.t. `inferType e` is definitionally equal to `expectedType`, return
   term `@id expectedType e`. -/
 def mkExpectedTypeHint (e : Expr) (expectedType : Expr) : MetaM Expr := do
   let u ← getLevel expectedType
@@ -38,13 +38,13 @@ def mkLetFun (x : Expr) (v : Expr) (e : Expr) : MetaM Expr := do
   let u2 ← getLevel ety
   return mkAppN (.const ``letFun [u1, u2]) #[α, β, v, f]
 
-/-- Returns `a = b`. -/
+/-- Return `a = b`. -/
 def mkEq (a b : Expr) : MetaM Expr := do
   let aType ← inferType a
   let u ← getLevel aType
   return mkApp3 (mkConst ``Eq [u]) aType a b
 
-/-- Returns `HEq a b`. -/
+/-- Return `HEq a b`. -/
 def mkHEq (a b : Expr) : MetaM Expr := do
   let aType ← inferType a
   let bType ← inferType b
@@ -52,7 +52,7 @@ def mkHEq (a b : Expr) : MetaM Expr := do
   return mkApp4 (mkConst ``HEq [u]) aType a bType b
 
 /--
-  If `a` and `b` have definitionally equal types, returns `Eq a b`, otherwise returns `HEq a b`.
+  If `a` and `b` have definitionally equal types, return `Eq a b`, otherwise return `HEq a b`.
 -/
 def mkEqHEq (a b : Expr) : MetaM Expr := do
   let aType ← inferType a
@@ -63,25 +63,25 @@ def mkEqHEq (a b : Expr) : MetaM Expr := do
   else
     return mkApp4 (mkConst ``HEq [u]) aType a bType b
 
-/-- Returns a proof of `a = a`. -/
+/-- Return a proof of `a = a`. -/
 def mkEqRefl (a : Expr) : MetaM Expr := do
   let aType ← inferType a
   let u ← getLevel aType
   return mkApp2 (mkConst ``Eq.refl [u]) aType a
 
-/-- Returns a proof of `HEq a a`. -/
+/-- Return a proof of `HEq a a`. -/
 def mkHEqRefl (a : Expr) : MetaM Expr := do
   let aType ← inferType a
   let u ← getLevel aType
   return mkApp2 (mkConst ``HEq.refl [u]) aType a
 
-/-- Given `hp : P` and `nhp : Not P`, returns an instance of type `e`. -/
+/-- Given `hp : P` and `nhp : Not P` returns an instance of type `e`. -/
 def mkAbsurd (e : Expr) (hp hnp : Expr) : MetaM Expr := do
   let p ← inferType hp
   let u ← getLevel e
   return mkApp4 (mkConst ``absurd [u]) p e hp hnp
 
-/-- Given `h : False`, returns an instance of type `e`. -/
+/-- Given `h : False`, return an instance of type `e`. -/
 def mkFalseElim (e : Expr) (h : Expr) : MetaM Expr := do
   let u ← getLevel e
   return mkApp2 (mkConst ``False.elim [u]) e h
@@ -108,7 +108,7 @@ def mkEqSymm (h : Expr) : MetaM Expr := do
       return mkApp4 (mkConst ``Eq.symm [u]) α a b h
     | none => throwAppBuilderException ``Eq.symm ("equality proof expected" ++ hasTypeMsg h hType)
 
-/-- Given `h₁ : a = b` and `h₂ : b = c`, returns a proof of `a = c`. -/
+/-- Given `h₁ : a = b` and `h₂ : b = c` returns a proof of `a = c`. -/
 def mkEqTrans (h₁ h₂ : Expr) : MetaM Expr := do
   if h₁.isAppOf ``Eq.refl then
     return h₂
@@ -185,7 +185,7 @@ def mkHEqOfEq (h : Expr) : MetaM Expr := do
   return mkApp4 (mkConst ``heq_of_eq [u]) α a b h
 
 /--
-If `e` is `@Eq.refl α a`, returns `a`.
+If `e` is `@Eq.refl α a`, return `a`.
 -/
 def isRefl? (e : Expr) : Option Expr := do
   if e.isAppOfArity ``Eq.refl 2 then
@@ -194,7 +194,7 @@ def isRefl? (e : Expr) : Option Expr := do
     none
 
 /--
-If `e` is `@congrArg α β a b f h`, returns `α`, `f` and `h`.
+If `e` is `@congrArg α β a b f h`, return `α`, `f` and `h`.
 Also works if `e` can be turned into such an application (e.g. `congrFun`).
 -/
 def congrArg? (e : Expr) : MetaM (Option (Expr × Expr × Expr)) := do
@@ -336,14 +336,13 @@ private def withAppBuilderTrace [ToMessageData α] [ToMessageData β]
       throw ex
 
 /--
-  Returns the application `constName xs`.
+  Return the application `constName xs`.
   It tries to fill the implicit arguments before the last element in `xs`.
 
   Remark:
   ``mkAppM `arbitrary #[α]`` returns `@arbitrary.{u} α` without synthesizing
   the implicit argument occurring after `α`.
-  Given a `x : ([Decidable p] → Bool) × Nat`, ``mkAppM `Prod.fst #[x]``,
-  returns `@Prod.fst ([Decidable p] → Bool) Nat x`.
+  Given a `x : ([Decidable p] → Bool) × Nat`, ``mkAppM `Prod.fst #[x]`` returns `@Prod.fst ([Decidable p] → Bool) Nat x`.
 -/
 def mkAppM (constName : Name) (xs : Array Expr) : MetaM Expr := do
   withAppBuilderTrace constName xs do withNewMCtxDepth do
@@ -466,9 +465,8 @@ def mkPure (monad : Expr) (e : Expr) : MetaM Expr :=
   mkAppOptM ``Pure.pure #[monad, none, none, e]
 
 /--
-`mkProjection s fieldName` returns an expression for accessing field `fieldName` of the structure `s`.
-Remark: `fieldName` may be a subfield of `s`.
--/
+  `mkProjection s fieldName` returns an expression for accessing field `fieldName` of the structure `s`.
+  Remark: `fieldName` may be a subfield of `s`. -/
 partial def mkProjection (s : Expr) (fieldName : Name) : MetaM Expr := do
   let type ← inferType s
   let type ← whnf type
@@ -522,11 +520,11 @@ def mkSome (type value : Expr) : MetaM Expr := do
   let u ← getDecLevel type
   return mkApp2 (mkConst ``Option.some [u]) type value
 
-/-- Returns `Decidable.decide p` -/
+/-- Return `Decidable.decide p` -/
 def mkDecide (p : Expr) : MetaM Expr :=
   mkAppOptM ``Decidable.decide #[p, none]
 
-/-- Returns a proof for `p : Prop` using `decide p` -/
+/-- Return a proof for `p : Prop` using `decide p` -/
 def mkDecideProof (p : Expr) : MetaM Expr := do
   let decP      ← mkDecide p
   let decEqTrue ← mkEq decP (mkConst ``Bool.true)
@@ -534,75 +532,59 @@ def mkDecideProof (p : Expr) : MetaM Expr := do
   let h         ← mkExpectedTypeHint h decEqTrue
   mkAppM ``of_decide_eq_true #[h]
 
-/-- Returns `a < b` -/
+/-- Return `a < b` -/
 def mkLt (a b : Expr) : MetaM Expr :=
   mkAppM ``LT.lt #[a, b]
 
-/-- Returns `a <= b` -/
+/-- Return `a <= b` -/
 def mkLe (a b : Expr) : MetaM Expr :=
   mkAppM ``LE.le #[a, b]
 
-/-- Returns `Inhabited.default α` -/
+/-- Return `Inhabited.default α` -/
 def mkDefault (α : Expr) : MetaM Expr :=
   mkAppOptM ``Inhabited.default #[α, none]
 
-/-- Returns `@Classical.ofNonempty α _` -/
+/-- Return `@Classical.ofNonempty α _` -/
 def mkOfNonempty (α : Expr) : MetaM Expr := do
   mkAppOptM ``Classical.ofNonempty #[α, none]
 
-/-- Returns `funext h` -/
+/-- Return `funext h` -/
 def mkFunExt (h : Expr) : MetaM Expr :=
   mkAppM ``funext #[h]
 
-/-- Returns `propext h` -/
+/-- Return `propext h` -/
 def mkPropExt (h : Expr) : MetaM Expr :=
   mkAppM ``propext #[h]
 
-/-- Returns `let_congr h₁ h₂` -/
+/-- Return `let_congr h₁ h₂` -/
 def mkLetCongr (h₁ h₂ : Expr) : MetaM Expr :=
   mkAppM ``let_congr #[h₁, h₂]
 
-/-- Returns `let_val_congr b h` -/
+/-- Return `let_val_congr b h` -/
 def mkLetValCongr (b h : Expr) : MetaM Expr :=
   mkAppM ``let_val_congr #[b, h]
 
-/-- Returns `let_body_congr a h` -/
+/-- Return `let_body_congr a h` -/
 def mkLetBodyCongr (a h : Expr) : MetaM Expr :=
   mkAppM ``let_body_congr #[a, h]
 
-/-- Returns `@of_eq_true p h` -/
-def mkOfEqTrueCore (p : Expr) (h : Expr) : Expr :=
-  match_expr h with
-  | eq_true _ h => h
-  | _ => mkApp2 (mkConst ``of_eq_true) p h
+/-- Return `of_eq_true h` -/
+def mkOfEqTrue (h : Expr) : MetaM Expr :=
+  mkAppM ``of_eq_true #[h]
 
-/-- Returns `of_eq_true h` -/
-def mkOfEqTrue (h : Expr) : MetaM Expr := do
-  match_expr h with
-  | eq_true _ h => return h
-  | _ => mkAppM ``of_eq_true #[h]
-
-/-- Returns `eq_true h` -/
-def mkEqTrueCore (p : Expr) (h : Expr) : Expr :=
-  match_expr h with
-  | of_eq_true _ h => h
-  | _ => mkApp2 (mkConst ``eq_true) p h
-
-/-- Returns `eq_true h` -/
-def mkEqTrue (h : Expr) : MetaM Expr := do
-  match_expr h with
-  | of_eq_true _ h => return h
-  | _ => return mkApp2 (mkConst ``eq_true) (← inferType h) h
+/-- Return `eq_true h` -/
+def mkEqTrue (h : Expr) : MetaM Expr :=
+  mkAppM ``eq_true #[h]
 
 /--
-  Returns `eq_false h`
+  Return `eq_false h`
   `h` must have type definitionally equal to `¬ p` in the current
   reducibility setting. -/
 def mkEqFalse (h : Expr) : MetaM Expr :=
   mkAppM ``eq_false #[h]
 
 /--
-  Returns `eq_false' h`
+  Return `eq_false' h`
   `h` must have type definitionally equal to `p → False` in the current
   reducibility setting. -/
 def mkEqFalse' (h : Expr) : MetaM Expr :=
@@ -620,7 +602,7 @@ def mkImpDepCongrCtx (h₁ h₂ : Expr) : MetaM Expr :=
 def mkForallCongr (h : Expr) : MetaM Expr :=
   mkAppM ``forall_congr #[h]
 
-/-- Returns instance for `[Monad m]` if there is one -/
+/-- Return instance for `[Monad m]` if there is one -/
 def isMonad? (m : Expr) : MetaM (Option Expr) :=
   try
     let monadType ← mkAppM `Monad #[m]
@@ -631,52 +613,52 @@ def isMonad? (m : Expr) : MetaM (Option Expr) :=
   catch _ =>
     pure none
 
-/-- Returns `(n : type)`, a numeric literal of type `type`. The method fails if we don't have an instance `OfNat type n` -/
+/-- Return `(n : type)`, a numeric literal of type `type`. The method fails if we don't have an instance `OfNat type n` -/
 def mkNumeral (type : Expr) (n : Nat) : MetaM Expr := do
   let u ← getDecLevel type
   let inst ← synthInstance (mkApp2 (mkConst ``OfNat [u]) type (mkRawNatLit n))
   return mkApp3 (mkConst ``OfNat.ofNat [u]) type (mkRawNatLit n) inst
 
 /--
-Returns `a op b`, where `op` has name `opName` and is implemented using the typeclass `className`.
-This method assumes `a` and `b` have the same type, and typeclass `className` is heterogeneous.
-Examples of supported classes: `HAdd`, `HSub`, `HMul`.
-We use heterogeneous operators to ensure we have a uniform representation.
--/
+  Return `a op b`, where `op` has name `opName` and is implemented using the typeclass `className`.
+  This method assumes `a` and `b` have the same type, and typeclass `className` is heterogeneous.
+  Examples of supported classes: `HAdd`, `HSub`, `HMul`.
+  We use heterogeneous operators to ensure we have a uniform representation.
+  -/
 private def mkBinaryOp (className : Name) (opName : Name) (a b : Expr) : MetaM Expr := do
   let aType ← inferType a
   let u ← getDecLevel aType
   let inst ← synthInstance (mkApp3 (mkConst className [u, u, u]) aType aType aType)
   return mkApp6 (mkConst opName [u, u, u]) aType aType aType inst a b
 
-/-- Returns `a + b` using a heterogeneous `+`. This method assumes `a` and `b` have the same type. -/
+/-- Return `a + b` using a heterogeneous `+`. This method assumes `a` and `b` have the same type. -/
 def mkAdd (a b : Expr) : MetaM Expr := mkBinaryOp ``HAdd ``HAdd.hAdd a b
 
-/-- Returns `a - b` using a heterogeneous `-`. This method assumes `a` and `b` have the same type. -/
+/-- Return `a - b` using a heterogeneous `-`. This method assumes `a` and `b` have the same type. -/
 def mkSub (a b : Expr) : MetaM Expr := mkBinaryOp ``HSub ``HSub.hSub a b
 
-/-- Returns `a * b` using a heterogeneous `*`. This method assumes `a` and `b` have the same type. -/
+/-- Return `a * b` using a heterogeneous `*`. This method assumes `a` and `b` have the same type. -/
 def mkMul (a b : Expr) : MetaM Expr := mkBinaryOp ``HMul ``HMul.hMul a b
 
 /--
-Returns `a r b`, where `r` has name `rName` and is implemented using the typeclass `className`.
-This method assumes `a` and `b` have the same type.
-Examples of supported classes: `LE` and `LT`.
-We use heterogeneous operators to ensure we have a uniform representation.
--/
+  Return `a r b`, where `r` has name `rName` and is implemented using the typeclass `className`.
+  This method assumes `a` and `b` have the same type.
+  Examples of supported classes: `LE` and `LT`.
+  We use heterogeneous operators to ensure we have a uniform representation.
+  -/
 private def mkBinaryRel (className : Name) (rName : Name) (a b : Expr) : MetaM Expr := do
   let aType ← inferType a
   let u ← getDecLevel aType
   let inst ← synthInstance (mkApp (mkConst className [u]) aType)
   return mkApp4 (mkConst rName [u]) aType inst a b
 
-/-- Returns `a ≤ b`. This method assumes `a` and `b` have the same type. -/
+/-- Return `a ≤ b`. This method assumes `a` and `b` have the same type. -/
 def mkLE (a b : Expr) : MetaM Expr := mkBinaryRel ``LE ``LE.le a b
 
-/-- Returns `a < b`. This method assumes `a` and `b` have the same type. -/
+/-- Return `a < b`. This method assumes `a` and `b` have the same type. -/
 def mkLT (a b : Expr) : MetaM Expr := mkBinaryRel ``LT ``LT.lt a b
 
-/-- Given `h : a = b`, returns a proof for `a ↔ b`. -/
+/-- Given `h : a = b`, return a proof for `a ↔ b`. -/
 def mkIffOfEq (h : Expr) : MetaM Expr := do
   if h.isAppOfArity ``propext 3 then
     return h.appArg!

src/Lean/Meta/Basic.lean

@@ -1964,22 +1964,15 @@ def sortFVarIds (fvarIds : Array FVarId) : MetaM (Array FVarId) := do
 
 end Methods
 
-/--
-Return `some info` if `declName` is an inductive predicate where `info : InductiveVal`.
-That is, `inductive` type in `Prop`.
--/
-def isInductivePredicate? (declName : Name) : MetaM (Option InductiveVal) := do
-  match (← getEnv).find? declName with
-  | some (.inductInfo info) =>
-    forallTelescopeReducing info.type fun _ type => do
-      match (← whnfD type) with
-      | .sort u .. => if u == levelZero then return some info else return none
-      | _ => return none
-  | _ => return none
-
 /-- Return `true` if `declName` is an inductive predicate. That is, `inductive` type in `Prop`. -/
 def isInductivePredicate (declName : Name) : MetaM Bool := do
-  return (← isInductivePredicate? declName).isSome
+  match (← getEnv).find? declName with
+  | some (.inductInfo { type := type, ..}) =>
+    forallTelescopeReducing type fun _ type => do
+      match (← whnfD type) with
+      | .sort u .. => return u == levelZero
+      | _ => return false
+  | _ => return false
 
 def isListLevelDefEqAux : List Level → List Level → MetaM Bool
   | [],    []    => return true

src/Lean/Meta/Tactic/Cases.lean

@@ -33,7 +33,7 @@ private def mkEqAndProof (lhs rhs : Expr) : MetaM (Expr × Expr) := do
   else
     pure (mkApp4 (mkConst ``HEq [u]) lhsType lhs rhsType rhs, mkApp2 (mkConst ``HEq.refl [u]) lhsType lhs)
 
-partial def withNewEqs (targets targetsNew : Array Expr) (k : Array Expr → Array Expr → MetaM α) : MetaM α :=
+private partial def withNewEqs (targets targetsNew : Array Expr) (k : Array Expr → Array Expr → MetaM α) : MetaM α :=
   let rec loop (i : Nat) (newEqs : Array Expr) (newRefls : Array Expr) := do
     if i < targets.size then
       let (newEqType, newRefl) ← mkEqAndProof targets[i]! targetsNew[i]!
@@ -66,31 +66,30 @@ structure GeneralizeIndicesSubgoal where
   numEqs         : Nat
 
 /--
-Given a metavariable `mvarId` representing the goal
-```
-Ctx |- T
-```
-and an expression `e : I A j`, where `I A j` is an inductive datatype where `A` are parameters,
-and `j` the indices. Generate the goal
-```
-Ctx, j' : J, h' : I A j' |- j == j' -> e == h' -> T
-```
-Remark: `(j == j' -> e == h')` is a "telescopic" equality.
-Remark: `j` is sequence of terms, and `j'` a sequence of free variables.
-The result contains the fields
-- `mvarId`: the new goal
-- `indicesFVarIds`: `j'` ids
-- `fvarId`: `h'` id
-- `numEqs`: number of equations in the target
-
-If `varName?` is not none, it is used to name `h'`.
--/
-def generalizeIndices' (mvarId : MVarId) (e : Expr) (varName? : Option Name := none) : MetaM GeneralizeIndicesSubgoal :=
+  Similar to `generalizeTargets` but customized for the `casesOn` motive.
+  Given a metavariable `mvarId` representing the
+  ```
+  Ctx, h : I A j, D |- T
+  ```
+  where `fvarId` is `h`s id, and the type `I A j` is an inductive datatype where `A` are parameters,
+  and `j` the indices. Generate the goal
+  ```
+  Ctx, h : I A j, D, j' : J, h' : I A j' |- j == j' -> h == h' -> T
+  ```
+  Remark: `(j == j' -> h == h')` is a "telescopic" equality.
+  Remark: `j` is sequence of terms, and `j'` a sequence of free variables.
+  The result contains the fields
+  - `mvarId`: the new goal
+  - `indicesFVarIds`: `j'` ids
+  - `fvarId`: `h'` id
+  - `numEqs`: number of equations in the target -/
+def generalizeIndices (mvarId : MVarId) (fvarId : FVarId) : MetaM GeneralizeIndicesSubgoal :=
   mvarId.withContext do
     let lctx       ← getLCtx
     let localInsts ← getLocalInstances
     mvarId.checkNotAssigned `generalizeIndices
-    let type ← whnfD (← inferType e)
+    let fvarDecl ← fvarId.getDecl
+    let type ← whnf fvarDecl.type
     type.withApp fun f args => matchConstInduct f (fun _ => throwTacticEx `generalizeIndices mvarId "inductive type expected") fun val _ => do
       unless val.numIndices > 0 do throwTacticEx `generalizeIndices mvarId "indexed inductive type expected"
       unless args.size == val.numIndices + val.numParams do throwTacticEx `generalizeIndices mvarId "ill-formed inductive datatype"
@@ -99,10 +98,9 @@ def generalizeIndices' (mvarId : MVarId) (e : Expr) (varName? : Option Name := n
       let IAType ← inferType IA
       forallTelescopeReducing IAType fun newIndices _ => do
       let newType := mkAppN IA newIndices
-      let varName ← if let some varName := varName? then pure varName else mkFreshUserName `x
-      withLocalDeclD varName newType fun h' =>
+      withLocalDeclD fvarDecl.userName newType fun h' =>
       withNewEqs indices newIndices fun newEqs newRefls => do
-      let (newEqType, newRefl) ← mkEqAndProof e h'
+      let (newEqType, newRefl) ← mkEqAndProof fvarDecl.toExpr h'
       let newRefls := newRefls.push newRefl
       withLocalDeclD `h newEqType fun newEq => do
       let newEqs := newEqs.push newEq
@@ -114,7 +112,7 @@ def generalizeIndices' (mvarId : MVarId) (e : Expr) (varName? : Option Name := n
       let auxType ← mkForallFVars newIndices auxType
       let newMVar ← mkFreshExprMVarAt lctx localInsts auxType MetavarKind.syntheticOpaque tag
       /- assign mvarId := newMVar indices h refls -/
-      mvarId.assign (mkAppN (mkApp (mkAppN newMVar indices) e) newRefls)
+      mvarId.assign (mkAppN (mkApp (mkAppN newMVar indices) fvarDecl.toExpr) newRefls)
       let (indicesFVarIds, newMVarId) ← newMVar.mvarId!.introNP newIndices.size
       let (fvarId, newMVarId) ← newMVarId.intro1P
       return {
@@ -124,29 +122,6 @@ def generalizeIndices' (mvarId : MVarId) (e : Expr) (varName? : Option Name := n
         numEqs         := newEqs.size
       }
 
-/--
-Similar to `generalizeTargets` but customized for the `casesOn` motive.
-Given a metavariable `mvarId` representing the
-```
-Ctx, h : I A j, D |- T
-```
-where `fvarId` is `h`s id, and the type `I A j` is an inductive datatype where `A` are parameters,
-and `j` the indices. Generate the goal
-```
-Ctx, h : I A j, D, j' : J, h' : I A j' |- j == j' -> h == h' -> T
-```
-Remark: `(j == j' -> h == h')` is a "telescopic" equality.
-Remark: `j` is sequence of terms, and `j'` a sequence of free variables.
-The result contains the fields
-- `mvarId`: the new goal
-- `indicesFVarIds`: `j'` ids
-- `fvarId`: `h'` id
-- `numEqs`: number of equations in the target -/
-def generalizeIndices (mvarId : MVarId) (fvarId : FVarId) : MetaM GeneralizeIndicesSubgoal :=
-  mvarId.withContext do
-    let fvarDecl ← fvarId.getDecl
-    generalizeIndices' mvarId fvarDecl.toExpr fvarDecl.userName
-
 structure CasesSubgoal extends InductionSubgoal where
   ctorName : Name
 

src/Lean/Meta/Tactic/FVarSubst.lean

@@ -35,7 +35,7 @@ def insert (s : FVarSubst) (fvarId : FVarId) (v : Expr) : FVarSubst :=
   if s.contains fvarId then s
   else
     let map := s.map.mapVal fun e => e.replaceFVarId fvarId v;
-    { map := map.insertNew fvarId v }
+    { map := map.insert fvarId v }
 
 def erase (s : FVarSubst) (fvarId : FVarId) : FVarSubst :=
   { map := s.map.erase fvarId }

src/Lean/Meta/Tactic/Grind.lean

@@ -23,8 +23,7 @@ import Lean.Meta.Tactic.Grind.Parser
 import Lean.Meta.Tactic.Grind.EMatchTheorem
 import Lean.Meta.Tactic.Grind.EMatch
 import Lean.Meta.Tactic.Grind.Main
-import Lean.Meta.Tactic.Grind.CasesMatch
-import Lean.Meta.Tactic.Grind.Arith
+
 
 namespace Lean
 
@@ -35,19 +34,10 @@ builtin_initialize registerTraceClass `grind.eqc
 builtin_initialize registerTraceClass `grind.internalize
 builtin_initialize registerTraceClass `grind.ematch
 builtin_initialize registerTraceClass `grind.ematch.pattern
-builtin_initialize registerTraceClass `grind.ematch.pattern.search
 builtin_initialize registerTraceClass `grind.ematch.instance
 builtin_initialize registerTraceClass `grind.ematch.instance.assignment
 builtin_initialize registerTraceClass `grind.issues
 builtin_initialize registerTraceClass `grind.simp
-builtin_initialize registerTraceClass `grind.split
-builtin_initialize registerTraceClass `grind.split.candidate
-builtin_initialize registerTraceClass `grind.split.resolved
-builtin_initialize registerTraceClass `grind.offset
-builtin_initialize registerTraceClass `grind.offset.dist
-builtin_initialize registerTraceClass `grind.offset.internalize
-builtin_initialize registerTraceClass `grind.offset.internalize.term (inherited := true)
-builtin_initialize registerTraceClass `grind.offset.propagate
 
 /-! Trace options for `grind` developers -/
 builtin_initialize registerTraceClass `grind.debug
@@ -57,9 +47,5 @@ builtin_initialize registerTraceClass `grind.debug.proof
 builtin_initialize registerTraceClass `grind.debug.proj
 builtin_initialize registerTraceClass `grind.debug.parent
 builtin_initialize registerTraceClass `grind.debug.final
-builtin_initialize registerTraceClass `grind.debug.forallPropagator
-builtin_initialize registerTraceClass `grind.debug.split
-builtin_initialize registerTraceClass `grind.debug.canon
-builtin_initialize registerTraceClass `grind.debug.offset
-builtin_initialize registerTraceClass `grind.debug.offset.proof
+
 end Lean

src/Lean/Meta/Tactic/Grind/Arith.lean

@@ -1,10 +0,0 @@
-/-
-Copyright (c) 2025 Amazon.com, Inc. or its affiliates. All Rights Reserved.
-Released under Apache 2.0 license as described in the file LICENSE.
-Authors: Leonardo de Moura
--/
-prelude
-import Lean.Meta.Tactic.Grind.Arith.Util
-import Lean.Meta.Tactic.Grind.Arith.Types
-import Lean.Meta.Tactic.Grind.Arith.Offset
-import Lean.Meta.Tactic.Grind.Arith.Main

src/Lean/Meta/Tactic/Grind/Arith/Internalize.lean

@@ -1,14 +0,0 @@
-/-
-Copyright (c) 2025 Amazon.com, Inc. or its affiliates. All Rights Reserved.
-Released under Apache 2.0 license as described in the file LICENSE.
-Authors: Leonardo de Moura
--/
-prelude
-import Lean.Meta.Tactic.Grind.Arith.Offset
-
-namespace Lean.Meta.Grind.Arith
-
-def internalize (e : Expr) : GoalM Unit := do
-  Offset.internalizeCnstr e
-
-end Lean.Meta.Grind.Arith

src/Lean/Meta/Tactic/Grind/Arith/Inv.lean

@@ -1,14 +0,0 @@
-/-
-Copyright (c) 2025 Amazon.com, Inc. or its affiliates. All Rights Reserved.
-Released under Apache 2.0 license as described in the file LICENSE.
-Authors: Leonardo de Moura
--/
-prelude
-import Lean.Meta.Tactic.Grind.Arith.Offset
-
-namespace Lean.Meta.Grind.Arith
-
-def checkInvariants : GoalM Unit :=
-  Offset.checkInvariants
-
-end Lean.Meta.Grind.Arith

src/Lean/Meta/Tactic/Grind/Arith/Main.lean

@@ -1,34 +0,0 @@
-/-
-Copyright (c) 2025 Amazon.com, Inc. or its affiliates. All Rights Reserved.
-Released under Apache 2.0 license as described in the file LICENSE.
-Authors: Leonardo de Moura
--/
-prelude
-import Lean.Meta.Tactic.Grind.PropagatorAttr
-import Lean.Meta.Tactic.Grind.Arith.Offset
-
-namespace Lean.Meta.Grind.Arith
-
-namespace Offset
-def isCnstr? (e : Expr) : GoalM (Option (Cnstr NodeId)) :=
-  return (← get).arith.offset.cnstrs.find? { expr := e }
-
-def assertTrue (c : Cnstr NodeId) (p : Expr) : GoalM Unit := do
-  addEdge c.u c.v c.k (← mkOfEqTrue p)
-
-def assertFalse (c : Cnstr NodeId) (p : Expr) : GoalM Unit := do
-  let p := mkOfNegEqFalse (← get').nodes c p
-  let c := c.neg
-  addEdge c.u c.v c.k p
-
-end Offset
-
-builtin_grind_propagator propagateLE ↓LE.le := fun e => do
-  if (← isEqTrue e) then
-    if let some c ← Offset.isCnstr? e then
-      Offset.assertTrue c (← mkEqTrueProof e)
-  if (← isEqFalse e) then
-    if let some c ← Offset.isCnstr? e then
-      Offset.assertFalse c (← mkEqFalseProof e)
-
-end Lean.Meta.Grind.Arith

src/Lean/Meta/Tactic/Grind/Arith/Model.lean

@@ -1,39 +0,0 @@
-/-
-Copyright (c) 2025 Amazon.com, Inc. or its affiliates. All Rights Reserved.
-Released under Apache 2.0 license as described in the file LICENSE.
-Authors: Leonardo de Moura
--/
-prelude
-import Lean.Meta.Basic
-import Lean.Meta.Tactic.Grind.Types
-
-namespace Lean.Meta.Grind.Arith.Offset
-/-- Construct a model that statisfies all offset constraints -/
-def mkModel (goal : Goal) : MetaM (Array (Expr × Nat)) := do
-  let s := goal.arith.offset
-  let nodes := s.nodes
-  let mut pre : Array (Option Int) := mkArray nodes.size none
-  for u in [:nodes.size] do
-    let val? := s.sources[u]!.foldl (init := @none Int) fun val? v k => Id.run do
-      let some va := pre[v]! | return val?
-      let val' := va - k
-      let some val := val? | return val'
-      if val' > val then return val' else val?
-    let val? := s.targets[u]!.foldl (init := val?) fun val? v k => Id.run do
-      let some va := pre[v]! | return val?
-      let val' := va + k
-      let some val := val? | return val'
-      if val' < val then return val' else val?
-    let val := val?.getD 0
-    pre := pre.set! u (some val)
-  let min := pre.foldl (init := 0) fun min val? => Id.run do
-    let some val := val? | return min
-    if val < min then val else min
-  let mut r := {}
-  for u in [:nodes.size] do
-    let some val := pre[u]! | unreachable!
-    let val := (val - min).toNat
-    r := r.push (nodes[u]!, val)
-  return r
-
-end Lean.Meta.Grind.Arith.Offset

src/Lean/Meta/Tactic/Grind/Arith/Offset.lean

@@ -1,255 +0,0 @@
-/-
-Copyright (c) 2025 Amazon.com, Inc. or its affiliates. All Rights Reserved.
-Released under Apache 2.0 license as described in the file LICENSE.
-Authors: Leonardo de Moura
--/
-prelude
-import Init.Grind.Offset
-import Lean.Meta.Tactic.Grind.Types
-import Lean.Meta.Tactic.Grind.Arith.ProofUtil
-
-namespace Lean.Meta.Grind.Arith.Offset
-/-!
-This module implements a decision procedure for offset constraints of the form:
-```
-x + k ≤ y
-x ≤ y + k
-```
-where `k` is a numeral.
-Each constraint is represented as an edge in a weighted graph.
-The constraint `x + k ≤ y` is represented as a negative edge.
-The shortest path between two nodes in the graph corresponds to an implied inequality.
-When adding a new edge, the state is considered unsatisfiable if the new edge creates a negative cycle.
-An incremental Floyd-Warshall algorithm is used to find the shortest paths between all nodes.
-This module can also handle offset equalities of the form `x + k = y` by representing them with two edges:
-```
-x + k ≤ y
-y ≤ x + k
-```
-The main advantage of this module over a full linear integer arithmetic procedure is
-its ability to efficiently detect all implied equalities and inequalities.
--/
-
-def get' : GoalM State := do
-  return (← get).arith.offset
-
-@[inline] def modify' (f : State → State) : GoalM Unit := do
-  modify fun s => { s with arith.offset := f s.arith.offset }
-
-def mkNode (expr : Expr) : GoalM NodeId := do
-  if let some nodeId := (← get').nodeMap.find? { expr } then
-    return nodeId
-  let nodeId : NodeId := (← get').nodes.size
-  trace[grind.offset.internalize.term] "{expr} ↦ #{nodeId}"
-  modify' fun s => { s with
-    nodes   := s.nodes.push expr
-    nodeMap := s.nodeMap.insert { expr } nodeId
-    sources := s.sources.push {}
-    targets := s.targets.push {}
-    proofs  := s.proofs.push {}
-  }
-  return nodeId
-
-private def getExpr (u : NodeId) : GoalM Expr := do
-  return (← get').nodes[u]!
-
-private def getDist? (u v : NodeId) : GoalM (Option Int) := do
-  return (← get').targets[u]!.find? v
-
-private def getProof? (u v : NodeId) : GoalM (Option ProofInfo) := do
-  return (← get').proofs[u]!.find? v
-
-/--
-Returns a proof for `u + k ≤ v` (or `u ≤ v + k`) where `k` is the
-shortest path between `u` and `v`.
--/
-private partial def mkProofForPath (u v : NodeId) : GoalM Expr := do
-  go (← getProof? u v).get!
-where
-  go (p : ProofInfo) : GoalM Expr := do
-    if u == p.w then
-      return p.proof
-    else
-      let p' := (← getProof? u p.w).get!
-      go (mkTrans (← get').nodes p' p v)
-
-/--
-Given a new edge edge `u --(kuv)--> v` justified by proof `huv` s.t.
-it creates a negative cycle with the existing path `v --{kvu}-->* u`, i.e., `kuv + kvu < 0`,
-this function closes the current goal by constructing a proof of `False`.
--/
-private def setUnsat (u v : NodeId) (kuv : Int) (huv : Expr) (kvu : Int) : GoalM Unit := do
-  assert! kuv + kvu < 0
-  let hvu ← mkProofForPath v u
-  let u ← getExpr u
-  let v ← getExpr v
-  closeGoal (mkUnsatProof u v kuv huv kvu hvu)
-
-/-- Sets the new shortest distance `k` between nodes `u` and `v`. -/
-private def setDist (u v : NodeId) (k : Int) : GoalM Unit := do
-  trace[grind.offset.dist] "{({ u, v, k : Cnstr NodeId})}"
-  modify' fun s => { s with
-    targets := s.targets.modify u fun es => es.insert v k
-    sources := s.sources.modify v fun es => es.insert u k
-  }
-
-private def setProof (u v : NodeId) (p : ProofInfo) : GoalM Unit := do
-  modify' fun s => { s with
-    proofs := s.proofs.modify u fun es => es.insert v p
-  }
-
-@[inline]
-private def forEachSourceOf (u : NodeId) (f : NodeId → Int → GoalM Unit) : GoalM Unit := do
-  (← get').sources[u]!.forM f
-
-@[inline]
-private def forEachTargetOf (u : NodeId) (f : NodeId → Int → GoalM Unit) : GoalM Unit := do
-  (← get').targets[u]!.forM f
-
-/-- Returns `true` if `k` is smaller than the shortest distance between `u` and `v` -/
-private def isShorter (u v : NodeId) (k : Int) : GoalM Bool := do
-  if let some k' ← getDist? u v then
-    return k < k'
-  else
-    return true
-
-/--
-Tries to assign `e` to `True`, which is represented by constraint `c` (from `u` to `v`), using the
-path `u --(k)--> v`.
--/
-private def propagateTrue (u v : NodeId) (k : Int) (c : Cnstr NodeId) (e : Expr) : GoalM Bool := do
-  if k ≤ c.k then
-    trace[grind.offset.propagate] "{{ u, v, k : Cnstr NodeId}} ==> {e} = True"
-    let kuv ← mkProofForPath u v
-    let u ← getExpr u
-    let v ← getExpr v
-    pushEqTrue e <| mkPropagateEqTrueProof u v k kuv c.k
-    return true
-  return false
-
-example (x y : Nat) : x + 2 ≤ y → ¬ (y ≤ x + 1) := by omega
-
-/--
-Tries to assign `e` to `False`, which is represented by constraint `c` (from `v` to `u`), using the
-path `u --(k)--> v`.
--/
-private def propagateFalse (u v : NodeId) (k : Int) (c : Cnstr NodeId) (e : Expr) : GoalM Bool := do
-  if k + c.k < 0 then
-    trace[grind.offset.propagate] "{{ u, v, k : Cnstr NodeId}} ==> {e} = False"
-    let kuv ← mkProofForPath u v
-    let u ← getExpr u
-    let v ← getExpr v
-    pushEqFalse e <| mkPropagateEqFalseProof u v k kuv c.k
-  return false
-
-/--
-Auxiliary function for implementing `propagateAll`.
-Traverses the constraints `c` (representing an expression `e`) s.t.
-`c.u = u` and `c.v = v`, it removes `c` from the list of constraints
-associated with `(u, v)` IF
-- `e` is already assigned, or
-- `f c e` returns true
--/
-@[inline]
-private def updateCnstrsOf (u v : NodeId) (f : Cnstr NodeId → Expr → GoalM Bool) : GoalM Unit := do
-  if let some cs := (← get').cnstrsOf.find? (u, v) then
-    let cs' ← cs.filterM fun (c, e) => do
-      if (← isEqTrue e <||> isEqFalse e) then
-        return false -- constraint was already assigned
-      else
-        return !(← f c e)
-    modify' fun s => { s with cnstrsOf := s.cnstrsOf.insert (u, v) cs' }
-
-/-- Performs constraint propagation. -/
-private def propagateAll (u v : NodeId) (k : Int) : GoalM Unit := do
-  updateCnstrsOf u v fun c e => return !(← propagateTrue u v k c e)
-  updateCnstrsOf v u fun c e => return !(← propagateFalse u v k c e)
-
-/--
-If `isShorter u v k`, updates the shortest distance between `u` and `v`.
-`w` is the penultimate node in the path from `u` to `v`.
--/
-private def updateIfShorter (u v : NodeId) (k : Int) (w : NodeId) : GoalM Unit := do
-  if (← isShorter u v k) then
-    setDist u v k
-    setProof u v (← getProof? w v).get!
-    propagateAll u v k
-
-/--
-Adds an edge `u --(k) --> v` justified by the proof term `p`, and then
-if no negative cycle was created, updates the shortest distance of affected
-node pairs.
--/
-def addEdge (u : NodeId) (v : NodeId) (k : Int) (p : Expr) : GoalM Unit := do
-  if (← isInconsistent) then return ()
-  if let some k' ← getDist? v u then
-    if k'+k < 0 then
-      setUnsat u v k p k'
-      return ()
-  if (← isShorter u v k) then
-    setDist u v k
-    setProof u v { w := u, k, proof := p }
-    propagateAll u v k
-    update
-where
-  update : GoalM Unit := do
-    forEachTargetOf v fun j k₂ => do
-      /- Check whether new path: `u -(k)-> v -(k₂)-> j` is shorter -/
-      updateIfShorter u j (k+k₂) v
-    forEachSourceOf u fun i k₁ => do
-      /- Check whether new path: `i -(k₁)-> u -(k)-> v` is shorter -/
-      updateIfShorter i v (k₁+k) u
-      forEachTargetOf v fun j k₂ => do
-        /- Check whether new path: `i -(k₁)-> u -(k)-> v -(k₂) -> j` is shorter -/
-        updateIfShorter i j (k₁+k+k₂) v
-
-def internalizeCnstr (e : Expr) : GoalM Unit := do
-  let some c := isNatOffsetCnstr? e | return ()
-  let u ← mkNode c.u
-  let v ← mkNode c.v
-  let c := { c with u, v }
-  if let some k ← getDist? u v then
-    if (← propagateTrue u v k c e) then
-      return ()
-  if let some k ← getDist? v u then
-    if (← propagateFalse v u k c e) then
-      return ()
-  trace[grind.offset.internalize] "{e} ↦ {c}"
-  modify' fun s => { s with
-    cnstrs   := s.cnstrs.insert { expr := e } c
-    cnstrsOf :=
-      let cs := if let some cs := s.cnstrsOf.find? (u, v) then (c, e) :: cs else [(c, e)]
-      s.cnstrsOf.insert (u, v) cs
-  }
-
-def traceDists : GoalM Unit := do
-  let s ← get'
-  for u in [:s.targets.size], es in s.targets.toArray do
-    for (v, k) in es do
-      trace[grind.offset.dist] "#{u} -({k})-> #{v}"
-
-def Cnstr.toExpr (c : Cnstr NodeId) : GoalM Expr := do
-  let u := (← get').nodes[c.u]!
-  let v := (← get').nodes[c.v]!
-  let mk := if c.le then mkNatLE else mkNatEq
-  if c.k == 0 then
-    return mk u v
-  else if c.k < 0 then
-    return mk (mkNatAdd u (Lean.toExpr ((-c.k).toNat))) v
-  else
-    return mk u (mkNatAdd v (Lean.toExpr c.k.toNat))
-
-def checkInvariants : GoalM Unit := do
-  let s ← get'
-  for u in [:s.targets.size], es in s.targets.toArray do
-    for (v, k) in es do
-      let c : Cnstr NodeId := { u, v, k }
-      trace[grind.debug.offset] "{c}"
-      let p ← mkProofForPath u v
-      trace[grind.debug.offset.proof] "{p} : {← inferType p}"
-      check p
-      unless (← withDefault <| isDefEq (← inferType p) (← Cnstr.toExpr c)) do
-        trace[grind.debug.offset.proof] "failed: {← inferType p} =?= {← Cnstr.toExpr c}"
-        unreachable!
-
-end Lean.Meta.Grind.Arith.Offset

src/Lean/Meta/Tactic/Grind/Arith/ProofUtil.lean

@@ -1,168 +0,0 @@
-/-
-Copyright (c) 2025 Amazon.com, Inc. or its affiliates. All Rights Reserved.
-Released under Apache 2.0 license as described in the file LICENSE.
-Authors: Leonardo de Moura
--/
-prelude
-import Init.Grind.Offset
-import Init.Grind.Lemmas
-import Lean.Meta.Tactic.Grind.Types
-
-namespace Lean.Meta.Grind.Arith
-
-/-!
-Helper functions for constructing proof terms in the arithmetic procedures.
--/
-
-namespace Offset
-
-/-- Returns a proof for `true = true` -/
-def rfl_true : Expr := mkConst ``Grind.rfl_true
-
-private def toExprN (n : Int) :=
-  assert! n >= 0
-  toExpr n.toNat
-
-open Lean.Grind in
-/--
-Assume `pi₁` is `{ w := u, k := k₁, proof := p₁ }` and `pi₂` is `{ w := w, k := k₂, proof := p₂ }`
-`p₁` is the proof for edge `u -(k₁) → w` and `p₂` the proof for edge `w -(k₂)-> v`.
-Then, this function returns a proof for edge `u -(k₁+k₂) -> v`.
--/
-def mkTrans (nodes : PArray Expr) (pi₁ : ProofInfo) (pi₂ : ProofInfo) (v : NodeId) : ProofInfo :=
-  let { w := u, k := k₁, proof := p₁ } := pi₁
-  let { w, k := k₂, proof := p₂ } := pi₂
-  let u := nodes[u]!
-  let w := nodes[w]!
-  let v := nodes[v]!
-  let p := if k₁ == 0 then
-    if k₂ == 0 then
-      -- u ≤ w, w ≤ v
-      mkApp5 (mkConst ``Nat.le_trans) u w v p₁ p₂
-    else if k₂ > 0 then
-      -- u ≤ v, w ≤ v + k₂
-      mkApp6 (mkConst ``Nat.le_ro) u w v (toExprN k₂) p₁ p₂
-    else
-      let k₂ := - k₂
-      -- u ≤ w, w + k₂ ≤ v
-      mkApp6 (mkConst ``Nat.le_lo) u w v (toExprN k₂) p₁ p₂
-  else if k₁ < 0 then
-    let k₁ := -k₁
-    if k₂ == 0 then
-      mkApp6 (mkConst ``Nat.lo_le) u w v (toExprN k₁) p₁ p₂
-    else if k₂ < 0 then
-      let k₂ := -k₂
-      mkApp7 (mkConst ``Nat.lo_lo) u w v (toExprN k₁) (toExprN k₂) p₁ p₂
-    else
-      let ke₁ := toExprN k₁
-      let ke₂ := toExprN k₂
-      if k₁ > k₂ then
-        mkApp8 (mkConst ``Nat.lo_ro_1) u w v ke₁ ke₂ rfl_true p₁ p₂
-      else
-        mkApp7 (mkConst ``Nat.lo_ro_2) u w v ke₁ ke₂ p₁ p₂
-  else
-    let ke₁ := toExprN k₁
-    if k₂ == 0 then
-      mkApp6 (mkConst ``Nat.ro_le) u w v ke₁ p₁ p₂
-    else if k₂ < 0 then
-      let k₂  := -k₂
-      let ke₂ := toExprN k₂
-       if k₂ > k₁ then
-         mkApp8 (mkConst ``Nat.ro_lo_2) u w v ke₁ ke₂ rfl_true p₁ p₂
-       else
-         mkApp7 (mkConst ``Nat.ro_lo_1) u w v ke₁ ke₂ p₁ p₂
-    else
-      let ke₂ := toExprN k₂
-      mkApp7 (mkConst ``Nat.ro_ro) u w v ke₁ ke₂ p₁ p₂
-  { w := pi₁.w, k := k₁+k₂, proof := p }
-
-open Lean.Grind in
-def mkOfNegEqFalse (nodes : PArray Expr) (c : Cnstr NodeId) (h : Expr) : Expr :=
-  let u := nodes[c.u]!
-  let v := nodes[c.v]!
-  if c.k == 0 then
-    mkApp3 (mkConst ``Nat.of_le_eq_false) u v h
-  else if c.k == -1 && c.le then
-    mkApp3 (mkConst ``Nat.of_lo_eq_false_1) u v h
-  else if c.k < 0 then
-    mkApp4 (mkConst ``Nat.of_lo_eq_false) u v (toExprN (-c.k)) h
-  else
-    mkApp4 (mkConst ``Nat.of_ro_eq_false) u v (toExprN c.k) h
-
-/--
-Returns a proof of `False` using a negative cycle composed of
-- `u --(kuv)--> v` with proof `huv`
-- `v --(kvu)--> u` with proof `hvu`
--/
-def mkUnsatProof (u v : Expr) (kuv : Int) (huv : Expr) (kvu : Int) (hvu : Expr) : Expr :=
-  if kuv == 0 then
-    assert! kvu < 0
-    mkApp6 (mkConst ``Grind.Nat.unsat_le_lo) u v (toExprN (-kvu)) rfl_true huv hvu
-  else if kvu == 0 then
-    mkApp6 (mkConst ``Grind.Nat.unsat_le_lo) v u (toExprN (-kuv)) rfl_true hvu huv
-  else if kuv < 0 then
-    if kvu > 0 then
-      mkApp7 (mkConst ``Grind.Nat.unsat_lo_ro) u v (toExprN (-kuv)) (toExprN kvu) rfl_true huv hvu
-    else
-      assert! kvu < 0
-      mkApp7 (mkConst ``Grind.Nat.unsat_lo_lo) u v (toExprN (-kuv)) (toExprN (-kvu)) rfl_true huv hvu
-  else
-    assert! kuv > 0 && kvu < 0
-    mkApp7 (mkConst ``Grind.Nat.unsat_lo_ro) v u (toExprN (-kvu)) (toExprN kuv) rfl_true hvu huv
-
-/--
-Given a path `u --(kuv)--> v` justified by proof `huv`,
-construct a proof of `e = True` where `e` is a term corresponding to the edgen `u --(k') --> v`
-s.t. `k ≤ k'`
--/
-def mkPropagateEqTrueProof (u v : Expr) (k : Int) (huv : Expr) (k' : Int) : Expr :=
-  if k == 0 then
-    if k' == 0 then
-      mkApp3 (mkConst ``Grind.Nat.le_eq_true_of_le) u v huv
-    else
-      assert! k' > 0
-      mkApp4 (mkConst ``Grind.Nat.ro_eq_true_of_le) u v (toExprN k') huv
-  else if k < 0 then
-    let k := -k
-    if k' == 0 then
-      mkApp4 (mkConst ``Grind.Nat.le_eq_true_of_lo) u v (toExprN k) huv
-    else if k' < 0 then
-      let k' := -k'
-      mkApp6 (mkConst ``Grind.Nat.lo_eq_true_of_lo) u v (toExprN k) (toExprN k') rfl_true huv
-    else
-      assert! k' > 0
-      mkApp5 (mkConst ``Grind.Nat.ro_eq_true_of_lo) u v (toExprN k) (toExprN k') huv
-  else
-    assert! k > 0
-    assert! k' > 0
-    mkApp6 (mkConst ``Grind.Nat.ro_eq_true_of_ro) u v (toExprN k) (toExprN k') rfl_true huv
-
-/--
-Given a path `u --(kuv)--> v` justified by proof `huv`,
-construct a proof of `e = False` where `e` is a term corresponding to the edgen `v --(k') --> u`
-s.t. `k+k' < 0`
--/
-def mkPropagateEqFalseProof (u v : Expr) (k : Int) (huv : Expr) (k' : Int) : Expr :=
-  if k == 0 then
-    assert! k' < 0
-    let k' := -k'
-    mkApp5 (mkConst ``Grind.Nat.lo_eq_false_of_le) u v (toExprN k') rfl_true huv
-  else if k < 0 then
-    let k := -k
-    if k' == 0 then
-      mkApp5 (mkConst ``Grind.Nat.le_eq_false_of_lo) u v (toExprN k) rfl_true huv
-    else if k' < 0 then
-      let k' := -k'
-      mkApp6 (mkConst ``Grind.Nat.lo_eq_false_of_lo) u v (toExprN k) (toExprN k') rfl_true huv
-    else
-      assert! k' > 0
-      mkApp6 (mkConst ``Grind.Nat.ro_eq_false_of_lo) u v (toExprN k) (toExprN k') rfl_true huv
-  else
-    assert! k > 0
-    assert! k' < 0
-    let k' := -k'
-    mkApp6 (mkConst ``Grind.Nat.lo_eq_false_of_ro) u v (toExprN k) (toExprN k') rfl_true huv
-
-end Offset
-
-end Lean.Meta.Grind.Arith

src/Lean/Meta/Tactic/Grind/Arith/Types.lean

@@ -1,66 +0,0 @@
-/-
-Copyright (c) 2025 Amazon.com, Inc. or its affiliates. All Rights Reserved.
-Released under Apache 2.0 license as described in the file LICENSE.
-Authors: Leonardo de Moura
--/
-prelude
-import Lean.Data.PersistentArray
-import Lean.Meta.Tactic.Grind.ENodeKey
-import Lean.Meta.Tactic.Grind.Arith.Util
-
-namespace Lean.Meta.Grind.Arith
-
-namespace Offset
-
-abbrev NodeId := Nat
-
-instance : ToMessageData (Offset.Cnstr NodeId) where
-  toMessageData c := Offset.toMessageData (α := NodeId) (inst := { toMessageData n := m!"#{n}" }) c
-
-/-- Auxiliary structure used for proof extraction.  -/
-structure ProofInfo where
-  w     : NodeId
-  k     : Int
-  proof : Expr
-  deriving Inhabited
-
-/-- State of the constraint offset procedure. -/
-structure State where
-  /-- Mapping from `NodeId` to the `Expr` represented by the node. -/
-  nodes    : PArray Expr := {}
-  /-- Mapping from `Expr` to a node representing it. -/
-  nodeMap  : PHashMap ENodeKey NodeId := {}
-  /-- Mapping from `Expr` representing inequalites to constraints. -/
-  cnstrs   : PHashMap ENodeKey (Cnstr NodeId) := {}
-  /--
-  Mapping from pairs `(u, v)` to a list of offset constraints on `u` and `v`.
-  We use this mapping to implement exhaustive constraint propagation.
-  -/
-  cnstrsOf : PHashMap (NodeId × NodeId) (List (Cnstr NodeId × Expr)) := {}
-  /--
-  For each node with id `u`, `sources[u]` contains
-  pairs `(v, k)` s.t. there is a path from `v` to `u` with weight `k`.
-  -/
-  sources  : PArray (AssocList NodeId Int) := {}
-  /--
-  For each node with id `u`, `targets[u]` contains
-  pairs `(v, k)` s.t. there is a path from `u` to `v` with weight `k`.
-  -/
-  targets  : PArray (AssocList NodeId Int) := {}
-  /--
-  Proof reconstruction information. For each node with id `u`, `proofs[u]` contains
-  pairs `(v, { w, proof })` s.t. there is a path from `u` to `v`, and
-  `w` is the penultimate node in the path, and `proof` is the justification for
-  the last edge.
-  -/
-  proofs   : PArray (AssocList NodeId ProofInfo) := {}
-  deriving Inhabited
-
-end Offset
-
-/-- State for the arithmetic procedures. -/
-structure State where
-  offset : Offset.State := {}
-  deriving Inhabited
-
-end Lean.Meta.Grind.Arith

src/Lean/Meta/Tactic/Grind/Arith/Util.lean

@@ -1,89 +0,0 @@
-/-
-Copyright (c) 2025 Amazon.com, Inc. or its affiliates. All Rights Reserved.
-Released under Apache 2.0 license as described in the file LICENSE.
-Authors: Leonardo de Moura
--/
-prelude
-import Lean.Expr
-import Lean.Message
-
-namespace Lean.Meta.Grind.Arith
-
-/-- Returns `true` if `e` is of the form `Nat` -/
-def isNatType (e : Expr) : Bool :=
-  e.isConstOf ``Nat
-
-/-- Returns `true` if `e` is of the form `@instHAdd Nat instAddNat` -/
-def isInstAddNat (e : Expr) : Bool :=
-  let_expr instHAdd a b := e | false
-  isNatType a && b.isConstOf ``instAddNat
-
-/-- Returns `true` if `e` is `instLENat` -/
-def isInstLENat (e : Expr) : Bool :=
-  e.isConstOf ``instLENat
-
-/--
-Returns `some (a, b)` if `e` is of the form
-```
-@HAdd.hAdd Nat Nat Nat (instHAdd Nat instAddNat) a b
-```
--/
-def isNatAdd? (e : Expr) : Option (Expr × Expr) :=
-  let_expr HAdd.hAdd _ _ _ i a b := e | none
-  if isInstAddNat i then some (a, b) else none
-
-/-- Returns `some k` if `e` `@OfNat.ofNat Nat _ (instOfNatNat k)` -/
-def isNatNum? (e : Expr) : Option Nat := Id.run do
-  let_expr OfNat.ofNat _ _ inst := e | none
-  let_expr instOfNatNat k := inst | none
-  let .lit (.natVal k) := k | none
-  some k
-
-/-- Returns `some (a, k)` if `e` is of the form `a + k`.  -/
-def isNatOffset? (e : Expr) : Option (Expr × Nat) := Id.run do
-  let some (a, b) := isNatAdd? e | none
-  let some k := isNatNum? b | none
-  some (a, k)
-
-/-- An offset constraint. -/
-structure Offset.Cnstr (α : Type) where
-  u  : α
-  v  : α
-  k  : Int := 0
-  le : Bool := true
-  deriving Inhabited
-
-def Offset.Cnstr.neg : Cnstr α → Cnstr α
-  | { u, v, k, le } => { u := v, v := u, le, k := -k - 1 }
-
-example (c : Offset.Cnstr α) : c.neg.neg = c := by
-  cases c; simp [Offset.Cnstr.neg]; omega
-
-def Offset.toMessageData [inst : ToMessageData α] (c : Offset.Cnstr α) : MessageData :=
-  match c.k, c.le with
-  | .ofNat 0,   true  => m!"{c.u} ≤ {c.v}"
-  | .ofNat 0,   false => m!"{c.u} = {c.v}"
-  | .ofNat k,   true  => m!"{c.u} ≤ {c.v} + {k}"
-  | .ofNat k,   false => m!"{c.u} = {c.v} + {k}"
-  | .negSucc k, true  => m!"{c.u} + {k + 1} ≤ {c.v}"
-  | .negSucc k, false => m!"{c.u} + {k + 1} = {c.v}"
-
-instance : ToMessageData (Offset.Cnstr Expr) where
-  toMessageData c := Offset.toMessageData c
-
-/-- Returns `some cnstr` if `e` is offset constraint. -/
-def isNatOffsetCnstr? (e : Expr) : Option (Offset.Cnstr Expr) :=
-  match_expr e with
-  | LE.le _ inst a b => if isInstLENat inst then go a b true else none
-  | Eq α a b => if isNatType α then go a b false else none
-  | _ => none
-where
-  go (u v : Expr) (le : Bool) :=
-    if let some (u, k) := isNatOffset? u then
-      some { u, k := - k, v, le }
-    else if let some (v, k) := isNatOffset? v then
-      some { u, v, k := k, le }
-    else
-      some { u, v, le }
-
-end Lean.Meta.Grind.Arith

src/Lean/Meta/Tactic/Grind/Canon.lean

@@ -22,7 +22,7 @@ to detect when two structurally different atoms are definitionally equal.
 The `grind` tactic, on the other hand, uses congruence closure. Moreover, types, type formers, proofs, and instances
 are considered supporting elements and are not factored into congruence detection.
 
-This module minimizes the number of `isDefEq` checks by comparing two terms `a` and `b` only if they are instances,
+This module minimizes the number of `isDefEq` checks by comparing two terms `a` and `b` only if they instances,
 types, or type formers and are the `i`-th arguments of two different `f`-applications. This approach is
 sufficient for the congruence closure procedure used by the `grind` tactic.
 
@@ -46,35 +46,15 @@ structure State where
   proofCanon : PHashMap Expr Expr := {}
   deriving Inhabited
 
-inductive CanonElemKind where
-  | /--
-    Type class instances are canonicalized using `TransparencyMode.instances`.
-    -/
-    instance
-  | /--
-    Types and Type formers are canonicalized using `TransparencyMode.default`.
-    Remark: propositions are just visited. We do not invoke `canonElemCore` for them.
-    -/
-    type
-  | /--
-    Implicit arguments that are not types, type formers, or instances, are canonicalized
-    using `TransparencyMode.reducible`
-    -/
-    implicit
-  deriving BEq
-
-def CanonElemKind.explain : CanonElemKind → String
-  | .instance => "type class instances"
-  | .type => "types (or type formers)"
-  | .implicit => "implicit arguments (which are not type class instances or types)"
-
 /--
 Helper function for canonicalizing `e` occurring as the `i`th argument of an `f`-application.
+`isInst` is true if `e` is an type class instance.
 
-Thus, if diagnostics are enabled, we also re-check them using `TransparencyMode.default`. If the result is different
+Recall that we use `TransparencyMode.instances` for checking whether two instances are definitionally equal or not.
+Thus, if diagnostics are enabled, we also check them using `TransparencyMode.default`. If the result is different
 we report to the user.
 -/
-def canonElemCore (f : Expr) (i : Nat) (e : Expr) (kind : CanonElemKind) : StateT State MetaM Expr := do
+def canonElemCore (f : Expr) (i : Nat) (e : Expr) (isInst : Bool) : StateT State MetaM Expr := do
   let s ← get
   if let some c := s.canon.find? e then
     return c
@@ -86,19 +66,16 @@ def canonElemCore (f : Expr) (i : Nat) (e : Expr) (kind : CanonElemKind) : State
       -- in general safe to replace `e` with `c` if `c` has more free variables than `e`.
       -- However, we don't revert previously canonicalized elements in the `grind` tactic.
       modify fun s => { s with canon := s.canon.insert e c }
-      trace[grind.debug.canon] "found {e} ===> {c}"
       return c
-    if kind != .type then
-      if (← isTracingEnabledFor `grind.issues <&&> (withDefault <| isDefEq e c)) then
+    if isInst then
+      if (← isDiagnosticsEnabled <&&> pure (c.fvarsSubset e) <&&> (withDefault <| isDefEq e c)) then
         -- TODO: consider storing this information in some structure that can be browsed later.
-        trace[grind.issues] "the following {kind.explain} are definitionally equal with `default` transparency but not with a more restrictive transparency{indentExpr e}\nand{indentExpr c}"
-  trace[grind.debug.canon] "({f}, {i}) ↦ {e}"
+        trace[grind.issues] "the following `grind` static elements are definitionally equal with `default` transparency, but not with `instances` transparency{indentExpr e}\nand{indentExpr c}"
   modify fun s => { s with canon := s.canon.insert e e, argMap := s.argMap.insert key (e::cs) }
   return e
 
-abbrev canonType (f : Expr) (i : Nat) (e : Expr) := withDefault <| canonElemCore f i e .type
-abbrev canonInst (f : Expr) (i : Nat) (e : Expr) := withReducibleAndInstances <| canonElemCore f i e .instance
-abbrev canonImplicit (f : Expr) (i : Nat) (e : Expr) := withReducible <| canonElemCore f i e .implicit
+abbrev canonType (f : Expr) (i : Nat) (e : Expr) := withDefault <| canonElemCore f i e false
+abbrev canonInst (f : Expr) (i : Nat) (e : Expr) := withReducibleAndInstances <| canonElemCore f i e true
 
 /--
 Return type for the `shouldCanon` function.
@@ -108,8 +85,6 @@ private inductive ShouldCanonResult where
     canonType
   | /- Nested instances are canonicalized. -/
     canonInst
-  | /- Implicit argument that is not an instance nor a type. -/
-    canonImplicit
   | /-
     Term is not a proof, type (former), nor an instance.
     Thus, it must be recursively visited by the canonizer.
@@ -117,13 +92,6 @@ private inductive ShouldCanonResult where
     visit
   deriving Inhabited
 
-instance : Repr ShouldCanonResult where
-  reprPrec r _ := match r with
-    | .canonType => "canonType"
-    | .canonInst => "canonInst"
-    | .canonImplicit => "canonImplicit"
-    | .visit => "visit"
-
 /--
 See comments at `ShouldCanonResult`.
 -/
@@ -134,14 +102,7 @@ def shouldCanon (pinfos : Array ParamInfo) (i : Nat) (arg : Expr) : MetaM Should
       return .canonInst
     else if pinfo.isProp then
       return .visit
-    else if pinfo.isImplicit then
-      if (← isTypeFormer arg) then
-        return .canonType
-      else
-        return .canonImplicit
-  if (← isProp arg) then
-    return .visit
-  else if (← isTypeFormer arg) then
+  if (← isTypeFormer arg) then
     return .canonType
   else
     return .visit
@@ -150,13 +111,22 @@ unsafe def canonImpl (e : Expr) : StateT State MetaM Expr := do
   visit e |>.run' mkPtrMap
 where
   visit (e : Expr) : StateRefT (PtrMap Expr Expr) (StateT State MetaM) Expr := do
-    unless e.isApp || e.isForall do return e
-    -- Check whether it is cached
-    if let some r := (← get).find? e then
-      return r
-    let e' ← match e with
-      | .app .. => e.withApp fun f args => do
-        if f.isConstOf ``Lean.Grind.nestedProof && args.size == 2 then
+    match e with
+    | .bvar .. => unreachable!
+    -- Recall that `grind` treats `let`, `forall`, and `lambda` as atomic terms.
+    | .letE .. | .forallE .. | .lam ..
+    | .const .. | .lit .. | .mvar .. | .sort .. | .fvar ..
+    -- Recall that the `grind` preprocessor uses the `foldProjs` preprocessing step.
+    | .proj ..
+    -- Recall that the `grind` preprocessor uses the `eraseIrrelevantMData` preprocessing step.
+    | .mdata ..  => return e
+    -- We only visit applications
+    | .app .. =>
+      -- Check whether it is cached
+      if let some r := (← get).find? e then
+        return r
+      e.withApp fun f args => do
+        let e' ← if f.isConstOf ``Lean.Grind.nestedProof && args.size == 2 then
           let prop := args[0]!
           let prop' ← visit prop
           if let some r := (← getThe State).proofCanon.find? prop' then
@@ -168,32 +138,24 @@ where
         else
           let pinfos := (← getFunInfo f).paramInfo
           let mut modified := false
-          let mut args := args.toVector
-          for h : i in [:args.size] do
-            let arg := args[i]
-            trace[grind.debug.canon] "[{repr (← shouldCanon pinfos i arg)}]: {arg} : {← inferType arg}"
+          let mut args := args
+          for i in [:args.size] do
+            let arg := args[i]!
             let arg' ← match (← shouldCanon pinfos i arg) with
             | .canonType  => canonType f i arg
             | .canonInst  => canonInst f i arg
-            | .canonImplicit => canonImplicit f i (← visit arg)
             | .visit      => visit arg
             unless ptrEq arg arg' do
-              args := args.set i arg'
+              args := args.set! i arg'
               modified := true
-          pure <| if modified then mkAppN f args.toArray else e
-      | .forallE _ d b _ =>
-        -- Recall that we have `ForallProp.lean`.
-        let d' ← visit d
-        -- Remark: users may not want to convert `p → q` into `¬p ∨ q`
-        let b' ← if b.hasLooseBVars then pure b else visit b
-        pure <| e.updateForallE! d' b'
-      | _ => unreachable!
-    modify fun s => s.insert e e'
-    return e'
+          pure <| if modified then mkAppN f args else e
+        modify fun s => s.insert e e'
+        return e'
 
-/-- Canonicalizes nested types, type formers, and instances in `e`. -/
-def canon (e : Expr) : StateT State MetaM Expr := do
-  trace[grind.debug.canon] "{e}"
+/--
+Canonicalizes nested types, type formers, and instances in `e`.
+-/
+def canon (e : Expr) : StateT State MetaM Expr :=
   unsafe canonImpl e
 
 end Canon

src/Lean/Meta/Tactic/Grind/Cases.lean

@@ -11,56 +11,52 @@ namespace Lean.Meta.Grind
 The `grind` tactic includes an auxiliary `cases` tactic that is not intended for direct use by users.
 This method implements it.
 This tactic is automatically applied when introducing local declarations with a type tagged with `[grind_cases]`.
-It is also used for "case-splitting" on terms during the search.
-
 It differs from the user-facing Lean `cases` tactic in the following ways:
 
 - It avoids unnecessary `revert` and `intro` operations.
 
 - It does not introduce new local declarations for each minor premise. Instead, the `grind` tactic preprocessor is responsible for introducing them.
 
+- It assumes that the major premise (i.e., the parameter `fvarId`) is the latest local declaration in the current goal.
+
 - If the major premise type is an indexed family, auxiliary declarations and (heterogeneous) equalities are introduced.
   However, these equalities are not resolved using `unifyEqs`. Instead, the `grind` tactic employs union-find and
   congruence closure to process these auxiliary equalities. This approach avoids applying substitution to propositions
   that have already been internalized by `grind`.
 -/
-def cases (mvarId : MVarId) (e : Expr) : MetaM (List MVarId) := mvarId.withContext do
+def cases (mvarId : MVarId) (fvarId : FVarId) : MetaM (List MVarId) := mvarId.withContext do
   let tag ← mvarId.getTag
-  let type ← whnf (← inferType e)
+  let type ← whnf (← fvarId.getType)
   let .const declName _ := type.getAppFn | throwInductiveExpected type
   let .inductInfo _ ← getConstInfo declName | throwInductiveExpected type
   let recursorInfo ← mkRecursorInfo (mkCasesOnName declName)
-  let k (mvarId : MVarId) (fvarId : FVarId) (indices : Array FVarId) : MetaM (List MVarId) := do
-    let indicesExpr := indices.map mkFVar
-    let recursor ← mkRecursorAppPrefix mvarId `grind.cases fvarId recursorInfo indicesExpr
-    let mut recursor := mkApp (mkAppN recursor indicesExpr) (mkFVar fvarId)
+  let k (mvarId : MVarId) (fvarId : FVarId) (indices : Array Expr) (clearMajor : Bool) : MetaM (List MVarId) := do
+    let recursor ← mkRecursorAppPrefix mvarId `grind.cases fvarId recursorInfo indices
+    let mut recursor := mkApp (mkAppN recursor indices) (mkFVar fvarId)
     let mut recursorType ← inferType recursor
     let mut mvarIdsNew := #[]
-    let mut idx := 1
     for _ in [:recursorInfo.numMinors] do
       let .forallE _ targetNew recursorTypeNew _ ← whnf recursorType
         | throwTacticEx `grind.cases mvarId "unexpected recursor type"
       recursorType := recursorTypeNew
-      let tagNew := if recursorInfo.numMinors > 1 then Name.num tag idx else tag
-      let mvar ← mkFreshExprSyntheticOpaqueMVar targetNew tagNew
+      let mvar ← mkFreshExprSyntheticOpaqueMVar targetNew tag
       recursor := mkApp recursor mvar
-      let mvarIdNew ← mvar.mvarId!.tryClearMany (indices.push fvarId)
+      let mvarIdNew ← if clearMajor then
+        mvar.mvarId!.clear fvarId
+      else
+        pure mvar.mvarId!
       mvarIdsNew := mvarIdsNew.push mvarIdNew
-      idx := idx + 1
     mvarId.assign recursor
     return mvarIdsNew.toList
   if recursorInfo.numIndices > 0 then
-    let s ← generalizeIndices' mvarId e
+    let s ← generalizeIndices mvarId fvarId
     s.mvarId.withContext do
-      k s.mvarId s.fvarId s.indicesFVarIds
-  else if let .fvar fvarId := e then
-    k mvarId fvarId #[]
+      k s.mvarId s.fvarId (s.indicesFVarIds.map mkFVar) (clearMajor := false)
   else
-    let mvarId ← mvarId.assert (← mkFreshUserName `x) type e
-    let (fvarId, mvarId) ← mvarId.intro1
-    mvarId.withContext do k mvarId fvarId #[]
+    let indices ← getMajorTypeIndices mvarId `grind.cases recursorInfo type
+    k mvarId fvarId indices (clearMajor := true)
 where
   throwInductiveExpected {α} (type : Expr) : MetaM α := do
-    throwTacticEx `grind.cases mvarId m!"(non-recursive) inductive type expected at {e}{indentExpr type}"
+    throwTacticEx `grind.cases mvarId m!"(non-recursive) inductive type expected at {mkFVar fvarId}{indentExpr type}"
 
 end Lean.Meta.Grind

src/Lean/Meta/Tactic/Grind/CasesMatch.lean

@@ -1,53 +0,0 @@
-/-
-Copyright (c) 2025 Amazon.com, Inc. or its affiliates. All Rights Reserved.
-Released under Apache 2.0 license as described in the file LICENSE.
-Authors: Leonardo de Moura
--/
-prelude
-import Lean.Meta.Tactic.Util
-import Lean.Meta.Tactic.Cases
-import Lean.Meta.Match.MatcherApp
-
-namespace Lean.Meta.Grind
-
-def casesMatch (mvarId : MVarId) (e : Expr) : MetaM (List MVarId) := mvarId.withContext do
-  let some app ← matchMatcherApp? e
-    | throwTacticEx `grind.casesMatch mvarId m!"`match`-expression expected{indentExpr e}"
-  let (motive, eqRefls) ← mkMotiveAndRefls app
-  let target ← mvarId.getType
-  let mut us := app.matcherLevels
-  if let some i := app.uElimPos? then
-    us := us.set! i (← getLevel target)
-  let splitterName := (← Match.getEquationsFor app.matcherName).splitterName
-  let splitterApp := mkConst splitterName us.toList
-  let splitterApp := mkAppN splitterApp app.params
-  let splitterApp := mkApp splitterApp motive
-  let splitterApp := mkAppN splitterApp app.discrs
-  let (mvars, _, _) ← forallMetaBoundedTelescope (← inferType splitterApp) app.alts.size (kind := .syntheticOpaque)
-  let splitterApp := mkAppN splitterApp mvars
-  let val := mkAppN splitterApp eqRefls
-  mvarId.assign val
-  updateTags mvars
-  return mvars.toList.map (·.mvarId!)
-where
-  mkMotiveAndRefls (app : MatcherApp) : MetaM (Expr × Array Expr) := do
-    let dummy := mkSort 0
-    let aux := mkApp (mkAppN e.getAppFn app.params) dummy
-    forallBoundedTelescope (← inferType aux) app.discrs.size fun xs _ => do
-    withNewEqs app.discrs xs fun eqs eqRefls => do
-      let type ← mvarId.getType
-      let type ← mkForallFVars eqs type
-      let motive ← mkLambdaFVars xs type
-      return (motive, eqRefls)
-
-  updateTags (mvars : Array Expr) : MetaM Unit := do
-    let tag ← mvarId.getTag
-    if mvars.size == 1 then
-      mvars[0]!.mvarId!.setTag tag
-    else
-      let mut idx := 1
-      for mvar in mvars do
-        mvar.mvarId!.setTag (Name.num tag idx)
-        idx := idx + 1
-
-end Lean.Meta.Grind

src/Lean/Meta/Tactic/Grind/Combinators.lean

@@ -1,71 +0,0 @@
-/-
-Copyright (c) 2025 Amazon.com, Inc. or its affiliates. All Rights Reserved.
-Released under Apache 2.0 license as described in the file LICENSE.
-Authors: Leonardo de Moura
--/
-prelude
-import Lean.Meta.Tactic.Grind.Types
-
-namespace Lean.Meta.Grind
-
-/-!
-Combinators for manipulating `GrindTactic`s.
-TODO: a proper tactic language for `grind`.
--/
-
-def GrindTactic := Goal → GrindM (Option (List Goal))
-
-def GrindTactic.try (x : GrindTactic) : GrindTactic := fun g => do
-  let some gs ← x g | return some [g]
-  return some gs
-
-def applyToAll (x : GrindTactic)  (goals : List Goal) : GrindM (List Goal) := do
-  go goals []
-where
-  go (goals : List Goal) (acc : List Goal) : GrindM (List Goal) := do
-    match goals with
-    | [] => return acc.reverse
-    | goal :: goals => match (← x goal) with
-      | none => go goals (goal :: acc)
-      | some goals' => go goals (goals' ++ acc)
-
-partial def GrindTactic.andThen (x y : GrindTactic) : GrindTactic := fun goal => do
-  let some goals ← x goal | return none
-  applyToAll y goals
-
-instance : AndThen GrindTactic where
-  andThen a b := GrindTactic.andThen a (b ())
-
-partial def GrindTactic.iterate (x : GrindTactic) : GrindTactic := fun goal => do
-  go [goal] []
-where
-  go (todo : List Goal) (result : List Goal) : GrindM (List Goal) := do
-    match todo with
-    | [] => return result
-    | goal :: todo =>
-      if let some goalsNew ← x goal then
-        go (goalsNew ++ todo) result
-      else
-        go todo (goal :: result)
-
-partial def GrindTactic.orElse (x y : GrindTactic) : GrindTactic := fun goal => do
-  let some goals ← x goal | y goal
-  return goals
-
-instance : OrElse GrindTactic where
-  orElse a b := GrindTactic.andThen a (b ())
-
-def toGrindTactic (f : GoalM Unit) : GrindTactic := fun goal => do
-  let goal ← GoalM.run' goal f
-  if goal.inconsistent then
-    return some []
-  else
-    return some [goal]
-
-def GrindTactic' := Goal → GrindM (List Goal)
-
-def GrindTactic'.toGrindTactic (x : GrindTactic') : GrindTactic := fun goal => do
-  let goals ← x goal
-  return some goals
-
-end Lean.Meta.Grind

src/Lean/Meta/Tactic/Grind/Core.lean

@@ -41,9 +41,8 @@ This is an auxiliary function performed while merging equivalence classes.
 private def removeParents (root : Expr) : GoalM ParentSet := do
   let parents ← getParentsAndReset root
   for parent in parents do
-    -- Recall that we may have `Expr.forallE` in `parents` because of `ForallProp.lean`
-    if (← pure parent.isApp <&&> isCongrRoot parent) then
-      trace_goal[grind.debug.parent] "remove: {parent}"
+    if (← isCongrRoot parent) then
+      trace[grind.debug.parent] "remove: {parent}"
       modify fun s => { s with congrTable := s.congrTable.erase { e := parent } }
   return parents
 
@@ -53,8 +52,8 @@ This is an auxiliary function performed while merging equivalence classes.
 -/
 private def reinsertParents (parents : ParentSet) : GoalM Unit := do
   for parent in parents do
-    if (← pure parent.isApp <&&> isCongrRoot parent) then
-      trace_goal[grind.debug.parent] "reinsert: {parent}"
+    if (← isCongrRoot parent) then
+      trace[grind.debug.parent] "reinsert: {parent}"
       addCongrTable parent
 
 /-- Closes the goal when `True` and `False` are in the same equivalence class. -/
@@ -91,9 +90,9 @@ private partial def addEqStep (lhs rhs proof : Expr) (isHEq : Bool) : GoalM Unit
   let rhsNode ← getENode rhs
   if isSameExpr lhsNode.root rhsNode.root then
     -- `lhs` and `rhs` are already in the same equivalence class.
-    trace_goal[grind.debug] "{← ppENodeRef lhs} and {← ppENodeRef rhs} are already in the same equivalence class"
+    trace[grind.debug] "{← ppENodeRef lhs} and {← ppENodeRef rhs} are already in the same equivalence class"
     return ()
-  trace_goal[grind.eqc] "{← if isHEq then mkHEq lhs rhs else mkEq lhs rhs}"
+  trace[grind.eqc] "{← if isHEq then mkHEq lhs rhs else mkEq lhs rhs}"
   let lhsRoot ← getENode lhsNode.root
   let rhsRoot ← getENode rhsNode.root
   let mut valueInconsistency := false
@@ -118,11 +117,11 @@ private partial def addEqStep (lhs rhs proof : Expr) (isHEq : Bool) : GoalM Unit
   unless (← isInconsistent) do
     if valueInconsistency then
       closeGoalWithValuesEq lhsRoot.self rhsRoot.self
-  trace_goal[grind.debug] "after addEqStep, {← (← get).ppState}"
+  trace[grind.debug] "after addEqStep, {← ppState}"
   checkInvariants
 where
   go (lhs rhs : Expr) (lhsNode rhsNode lhsRoot rhsRoot : ENode) (flipped : Bool) : GoalM Unit := do
-    trace_goal[grind.debug] "adding {← ppENodeRef lhs} ↦ {← ppENodeRef rhs}"
+    trace[grind.debug] "adding {← ppENodeRef lhs} ↦ {← ppENodeRef rhs}"
     /-
     We have the following `target?/proof?`
     `lhs -> ... -> lhsNode.root`
@@ -139,9 +138,8 @@ where
     }
     let parents ← removeParents lhsRoot.self
     updateRoots lhs rhsNode.root
-    trace_goal[grind.debug] "{← ppENodeRef lhs} new root {← ppENodeRef rhsNode.root}, {← ppENodeRef (← getRoot lhs)}"
+    trace[grind.debug] "{← ppENodeRef lhs} new root {← ppENodeRef rhsNode.root}, {← ppENodeRef (← getRoot lhs)}"
     reinsertParents parents
-    propagateEqcDown lhs
     setENode lhsNode.root { (← getENode lhsRoot.self) with -- We must retrieve `lhsRoot` since it was updated.
       next := rhsRoot.next
     }
@@ -159,13 +157,14 @@ where
       updateMT rhsRoot.self
 
   updateRoots (lhs : Expr) (rootNew : Expr) : GoalM Unit := do
-    traverseEqc lhs fun n =>
-      setENode n.self { n with root := rootNew }
-
-  propagateEqcDown (lhs : Expr) : GoalM Unit := do
-    traverseEqc lhs fun n =>
+    let rec loop (e : Expr) : GoalM Unit := do
+      let n ← getENode e
+      setENode e { n with root := rootNew }
       unless (← isInconsistent) do
-        propagateDown n.self
+        propagateDown e
+      if isSameExpr lhs n.next then return ()
+      loop n.next
+    loop lhs
 
 /-- Ensures collection of equations to be processed is empty. -/
 private def resetNewEqs : GoalM Unit :=
@@ -191,29 +190,17 @@ where
     addEqStep lhs rhs proof isHEq
     processTodo
 
-/-- Adds a new equality `lhs = rhs`. It assumes `lhs` and `rhs` have already been internalized. -/
-private def addEq (lhs rhs proof : Expr) : GoalM Unit := do
+def addEq (lhs rhs proof : Expr) : GoalM Unit := do
   addEqCore lhs rhs proof false
 
-/-- Adds a new heterogeneous equality `HEq lhs rhs`. It assumes `lhs` and `rhs` have already been internalized. -/
-private def addHEq (lhs rhs proof : Expr) : GoalM Unit := do
+def addHEq (lhs rhs proof : Expr) : GoalM Unit := do
   addEqCore lhs rhs proof true
 
-/-- Save asserted facts for pretty printing goal. -/
-private def storeFact (fact : Expr) : GoalM Unit := do
-  modify fun s => { s with facts := s.facts.push fact }
-
-/-- Internalizes `lhs` and `rhs`, and then adds equality `lhs = rhs`. -/
-def addNewEq (lhs rhs proof : Expr) (generation : Nat) : GoalM Unit := do
-  storeFact (← mkEq lhs rhs)
-  internalize lhs generation
-  internalize rhs generation
-  addEq lhs rhs proof
-
-/-- Adds a new `fact` justified by the given proof and using the given generation. -/
+/--
+Adds a new `fact` justified by the given proof and using the given generation.
+-/
 def add (fact : Expr) (proof : Expr) (generation := 0) : GoalM Unit := do
-  storeFact fact
-  trace_goal[grind.assert] "{fact}"
+  trace[grind.assert] "{fact}"
   if (← isInconsistent) then return ()
   resetNewEqs
   let_expr Not p := fact
@@ -222,22 +209,14 @@ def add (fact : Expr) (proof : Expr) (generation := 0) : GoalM Unit := do
 where
   go (p : Expr) (isNeg : Bool) : GoalM Unit := do
     match_expr p with
-    | Eq α lhs rhs =>
-      if α.isProp then
-        -- It is morally an iff.
-        -- We do not use the `goEq` optimization because we want to register `p` as a case-split
-        goFact p isNeg
-      else
-        goEq p lhs rhs isNeg false
+    | Eq _ lhs rhs => goEq p lhs rhs isNeg false
     | HEq _ lhs _ rhs => goEq p lhs rhs isNeg true
-    | _ => goFact p isNeg
-
-  goFact (p : Expr) (isNeg : Bool) : GoalM Unit := do
-    internalize p generation
-    if isNeg then
-      addEq p (← getFalseExpr) (← mkEqFalse proof)
-    else
-      addEq p (← getTrueExpr) (← mkEqTrue proof)
+    | _ =>
+      internalize p generation
+      if isNeg then
+        addEq p (← getFalseExpr) (← mkEqFalse proof)
+      else
+        addEq p (← getTrueExpr) (← mkEqTrue proof)
 
   goEq (p : Expr) (lhs rhs : Expr) (isNeg : Bool) (isHEq : Bool) : GoalM Unit := do
     if isNeg then

src/Lean/Meta/Tactic/Grind/Ctor.lean

@@ -9,18 +9,14 @@ import Lean.Meta.Tactic.Grind.Types
 namespace Lean.Meta.Grind
 
 private partial def propagateInjEqs (eqs : Expr) (proof : Expr) : GoalM Unit := do
-  -- Remark: we must use `shareCommon` before using `pushEq` and `pushHEq`.
-  -- This is needed because the result type of the injection theorem may allocate
   match_expr eqs with
   | And left right =>
     propagateInjEqs left (.proj ``And 0 proof)
     propagateInjEqs right (.proj ``And 1 proof)
-  | Eq _ lhs rhs    =>
-    pushEq (← shareCommon lhs) (← shareCommon rhs) proof
-  | HEq _ lhs _ rhs =>
-    pushHEq (← shareCommon lhs) (← shareCommon rhs) proof
+  | Eq _ lhs rhs    => pushEq lhs rhs proof
+  | HEq _ lhs _ rhs => pushHEq lhs rhs proof
   | _ =>
-   trace_goal[grind.issues] "unexpected injectivity theorem result type{indentExpr eqs}"
+   trace[grind.issues] "unexpected injectivity theorem result type{indentExpr eqs}"
    return ()
 
 /--

src/Lean/Meta/Tactic/Grind/DoNotSimp.lean

@@ -1,35 +0,0 @@
-/-
-Copyright (c) 2025 Amazon.com, Inc. or its affiliates. All Rights Reserved.
-Released under Apache 2.0 license as described in the file LICENSE.
-Authors: Leonardo de Moura
--/
-prelude
-import Init.Grind.Util
-import Init.Simproc
-import Lean.Meta.Tactic.Simp.Simproc
-
-namespace Lean.Meta.Grind
-
-/--
-Returns `Grind.doNotSimp e`.
-Recall that `Grind.doNotSimp` is an identity function, but the following simproc is used to prevent the term `e` from being simplified.
--/
-def markAsDoNotSimp (e : Expr) : MetaM Expr :=
-  mkAppM ``Grind.doNotSimp #[e]
-
-builtin_dsimproc_decl reduceDoNotSimp (Grind.doNotSimp _) := fun e => do
-  let_expr Grind.doNotSimp _ _ ← e | return .continue
-  return .done e
-
-/-- Adds `reduceDoNotSimp` to `s` -/
-def addDoNotSimp (s : Simprocs) : CoreM Simprocs := do
-  s.add ``reduceDoNotSimp (post := false)
-
-/-- Erases `Grind.doNotSimp` annotations. -/
-def eraseDoNotSimp (e : Expr) : CoreM Expr := do
-  let pre (e : Expr) := do
-    let_expr Grind.doNotSimp _ a := e | return .continue e
-    return .continue a
-  Core.transform e (pre := pre)
-
-end Lean.Meta.Grind

src/Lean/Meta/Tactic/Grind/EMatch.lean

@@ -6,7 +6,6 @@ Authors: Leonardo de Moura
 prelude
 import Lean.Meta.Tactic.Grind.Types
 import Lean.Meta.Tactic.Grind.Intro
-import Lean.Meta.Tactic.Grind.DoNotSimp
 
 namespace Lean.Meta.Grind
 namespace EMatch
@@ -16,8 +15,6 @@ namespace EMatch
 inductive Cnstr where
   | /-- Matches pattern `pat` with term `e` -/
     «match» (pat : Expr) (e : Expr)
-  | /-- Matches offset pattern `pat+k` with term `e` -/
-    offset (pat : Expr) (k : Nat) (e : Expr)
   | /-- This constraint is used to encode multi-patterns. -/
     «continue» (pat : Expr)
   deriving Inhabited
@@ -51,8 +48,6 @@ structure Context where
   useMT : Bool := true
   /-- `EMatchTheorem` being processed. -/
   thm   : EMatchTheorem := default
-  /-- Initial application used to start E-matching -/
-  initApp : Expr := default
   deriving Inhabited
 
 /-- State for the E-matching monad -/
@@ -66,9 +61,6 @@ abbrev M := ReaderT Context $ StateRefT State GoalM
 def M.run' (x : M α) : GoalM α :=
   x {} |>.run' {}
 
-@[inline] private abbrev withInitApp (e : Expr) (x : M α) : M α :=
-  withReader (fun ctx => { ctx with initApp := e }) x
-
 /--
 Assigns `bidx := e` in `c`. If `bidx` is already assigned in `c`, we check whether
 `e` and `c.assignment[bidx]` are in the same equivalence class.
@@ -95,28 +87,6 @@ private def eqvFunctions (pFn eFn : Expr) : Bool :=
   (pFn.isFVar && pFn == eFn)
   || (pFn.isConst && eFn.isConstOf pFn.constName!)
 
-/-- Matches a pattern argument. See `matchArgs?`. -/
-private def matchArg? (c : Choice) (pArg : Expr) (eArg : Expr) : OptionT GoalM Choice := do
-  if isPatternDontCare pArg then
-    return c
-  else if pArg.isBVar then
-    assign? c pArg.bvarIdx! eArg
-  else if let some pArg := groundPattern? pArg then
-    guard (← isEqv pArg eArg)
-    return c
-  else if let some (pArg, k) := isOffsetPattern? pArg then
-    assert! Option.isNone <| isOffsetPattern? pArg
-    assert! !isPatternDontCare pArg
-    return { c with cnstrs := .offset pArg k eArg :: c.cnstrs }
-  else
-    return { c with cnstrs := .match pArg eArg :: c.cnstrs }
-
-private def Choice.updateGen (c : Choice) (gen : Nat) : Choice :=
-  { c with gen := Nat.max gen c.gen }
-
-private def pushChoice (c : Choice) : M Unit :=
-  modify fun s => { s with choiceStack := c :: s.choiceStack }
-
 /--
 Matches arguments of pattern `p` with term `e`. Returns `some` if successful,
 and `none` otherwise. It may update `c`s assignment and list of contraints to be
@@ -126,8 +96,16 @@ private partial def matchArgs? (c : Choice) (p : Expr) (e : Expr) : OptionT Goal
   if !p.isApp then return c -- Done
   let pArg := p.appArg!
   let eArg := e.appArg!
-  let c ← matchArg? c pArg eArg
-  matchArgs? c p.appFn! e.appFn!
+  let goFn c := matchArgs? c p.appFn! e.appFn!
+  if isPatternDontCare pArg then
+    goFn c
+  else if pArg.isBVar then
+    goFn (← assign? c pArg.bvarIdx! eArg)
+  else if let some pArg := groundPattern? pArg then
+    guard (← isEqv pArg eArg)
+    goFn c
+  else
+    goFn { c with cnstrs := .match pArg eArg :: c.cnstrs }
 
 /--
 Matches pattern `p` with term `e` with respect to choice `c`.
@@ -142,46 +120,15 @@ private partial def processMatch (c : Choice) (p : Expr) (e : Expr) : M Unit :=
   let mut curr := e
   repeat
     let n ← getENode curr
-    -- Remark: we use `<` because the instance generation is the maximum term generation + 1
-    if n.generation < maxGeneration
+    if n.generation <= maxGeneration
        -- uses heterogeneous equality or is the root of its congruence class
        && (n.heqProofs || n.isCongrRoot)
        && eqvFunctions pFn curr.getAppFn
        && curr.getAppNumArgs == numArgs then
       if let some c ← matchArgs? c p curr |>.run then
-        pushChoice (c.updateGen n.generation)
-    curr ← getNext curr
-    if isSameExpr curr e then break
-
-/--
-Matches offset pattern `pArg+k` with term `e` with respect to choice `c`.
--/
-private partial def processOffset (c : Choice) (pArg : Expr) (k : Nat) (e : Expr) : M Unit := do
-  let maxGeneration ← getMaxGeneration
-  let mut curr := e
-  repeat
-    let n ← getENode curr
-    if n.generation < maxGeneration then
-      if let some (eArg, k') ← isOffset? curr |>.run then
-        if k' < k then
-          let c := c.updateGen n.generation
-          pushChoice { c with cnstrs := .offset pArg (k - k') eArg :: c.cnstrs }
-        else if k' == k then
-          if let some c ← matchArg? c pArg eArg |>.run then
-            pushChoice (c.updateGen n.generation)
-        else if k' > k then
-          let eArg' := mkNatAdd eArg (mkNatLit (k' - k))
-          let eArg' ← shareCommon (← canon eArg')
-          internalize eArg' (n.generation+1)
-          if let some c ← matchArg? c pArg eArg' |>.run then
-            pushChoice (c.updateGen n.generation)
-      else if let some k' ← evalNat curr |>.run then
-        if k' >= k then
-          let eArg' := mkNatLit (k' - k)
-          let eArg' ← shareCommon (← canon eArg')
-          internalize eArg' (n.generation+1)
-          if let some c ← matchArg? c pArg eArg' |>.run then
-            pushChoice (c.updateGen n.generation)
+        let gen := n.generation
+        let c := { c with gen := Nat.max gen c.gen }
+        modify fun s => { s with choiceStack := c :: s.choiceStack }
     curr ← getNext curr
     if isSameExpr curr e then break
 
@@ -192,26 +139,13 @@ private def processContinue (c : Choice) (p : Expr) : M Unit := do
   let maxGeneration ← getMaxGeneration
   for app in apps do
     let n ← getENode app
-    if n.generation < maxGeneration
+    if n.generation <= maxGeneration
        && (n.heqProofs || n.isCongrRoot) then
       if let some c ← matchArgs? c p app |>.run then
         let gen := n.generation
         let c := { c with gen := Nat.max gen c.gen }
         modify fun s => { s with choiceStack := c :: s.choiceStack }
 
-/--
-Helper function for marking parts of `match`-equation theorem as "do-not-simplify"
-`initApp` is the match-expression used to instantiate the `match`-equation.
--/
-private partial def annotateMatchEqnType (prop : Expr) (initApp : Expr) : M Expr := do
-  if let .forallE n d b bi := prop then
-    withLocalDecl n bi (← markAsDoNotSimp d) fun x => do
-      mkForallFVars #[x] (← annotateMatchEqnType (b.instantiate1 x) initApp)
-  else
-    let_expr f@Eq α lhs rhs := prop | return prop
-    -- See comment at `Grind.EqMatch`
-    return mkApp4 (mkConst ``Grind.EqMatch f.constLevels!) α (← markAsDoNotSimp lhs) rhs initApp
-
 /--
 Stores new theorem instance in the state.
 Recall that new instances are internalized later, after a full round of ematching.
@@ -220,11 +154,9 @@ private def addNewInstance (origin : Origin) (proof : Expr) (generation : Nat) :
   let proof ← instantiateMVars proof
   if grind.debug.proofs.get (← getOptions) then
     check proof
-  let mut prop ← inferType proof
-  if Match.isMatchEqnTheorem (← getEnv) origin.key then
-    prop ← annotateMatchEqnType prop (← read).initApp
-  trace_goal[grind.ematch.instance] "{← origin.pp}: {prop}"
-  addTheoremInstance proof prop (generation+1)
+  let prop ← inferType proof
+  trace[grind.ematch.instance] "{← origin.pp}: {prop}"
+  addTheoremInstance proof prop generation
 
 /--
 After processing a (multi-)pattern, use the choice assignment to instantiate the proof.
@@ -234,38 +166,36 @@ private partial def instantiateTheorem (c : Choice) : M Unit := withDefault do w
   let thm := (← read).thm
   unless (← markTheoremInstance thm.proof c.assignment) do
     return ()
-  trace_goal[grind.ematch.instance.assignment] "{← thm.origin.pp}: {assignmentToMessageData c.assignment}"
+  trace[grind.ematch.instance.assignment] "{← thm.origin.pp}: {assignmentToMessageData c.assignment}"
   let proof ← thm.getProofWithFreshMVarLevels
   let numParams := thm.numParams
   assert! c.assignment.size == numParams
   let (mvars, bis, _) ← forallMetaBoundedTelescope (← inferType proof) numParams
   if mvars.size != thm.numParams then
-    trace_goal[grind.issues] "unexpected number of parameters at {← thm.origin.pp}"
+    trace[grind.issues] "unexpected number of parameters at {← thm.origin.pp}"
     return ()
   -- Apply assignment
   for h : i in [:mvars.size] do
     let v := c.assignment[numParams - i - 1]!
     unless isSameExpr v unassigned do
       let mvarId := mvars[i].mvarId!
-      let mvarIdType ← mvarId.getType
-      let vType ← inferType v
-      unless (← isDefEq mvarIdType vType <&&> mvarId.checkedAssign v) do
-        trace_goal[grind.issues] "type error constructing proof for {← thm.origin.pp}\nwhen assigning metavariable {mvars[i]} with {indentExpr v}\n{← mkHasTypeButIsExpectedMsg vType mvarIdType}"
+      unless (← isDefEq (← mvarId.getType) (← inferType v) <&&> mvarId.checkedAssign v) do
+        trace[grind.issues] "type error constructing proof for {← thm.origin.pp}\nwhen assigning metavariable {mvars[i]} with {indentExpr v}"
         return ()
   -- Synthesize instances
   for mvar in mvars, bi in bis do
     if bi.isInstImplicit && !(← mvar.mvarId!.isAssigned) then
       let type ← inferType mvar
       unless (← synthesizeInstance mvar type) do
-        trace_goal[grind.issues] "failed to synthesize instance when instantiating {← thm.origin.pp}{indentExpr type}"
+        trace[grind.issues] "failed to synthesize instance when instantiating {← thm.origin.pp}{indentExpr type}"
         return ()
-  let proof := mkAppN proof mvars
   if (← mvars.allM (·.mvarId!.isAssigned)) then
-    addNewInstance thm.origin proof c.gen
+    addNewInstance thm.origin (mkAppN proof mvars) c.gen
   else
+    let proof := mkAppN proof mvars
     let mvars ← mvars.filterM fun mvar => return !(← mvar.mvarId!.isAssigned)
     if let some mvarBad ← mvars.findM? fun mvar => return !(← isProof mvar) then
-      trace_goal[grind.issues] "failed to instantiate {← thm.origin.pp}, failed to instantiate non propositional argument with type{indentExpr (← inferType mvarBad)}"
+      trace[grind.issues] "failed to instantiate {← thm.origin.pp}, failed to instantiate non propositional argument with type{indentExpr (← inferType mvarBad)}"
     let proof ← mkLambdaFVars (binderInfoForMVars := .default) mvars (← instantiateMVars proof)
     addNewInstance thm.origin proof c.gen
 where
@@ -274,18 +204,16 @@ where
     isDefEq x val
 
 /-- Process choice stack until we don't have more choices to be processed. -/
-private def processChoices : M Unit := do
-  let maxGeneration ← getMaxGeneration
-  while !(← get).choiceStack.isEmpty do
+private partial def processChoices : M Unit := do
+  unless (← get).choiceStack.isEmpty do
     checkSystem "ematch"
     if (← checkMaxInstancesExceeded) then return ()
     let c ← modifyGet fun s : State => (s.choiceStack.head!, { s with choiceStack := s.choiceStack.tail! })
-    if c.gen < maxGeneration then
-      match c.cnstrs with
-      | [] => instantiateTheorem c
-      | .match p e :: cnstrs => processMatch { c with cnstrs } p e
-      | .offset p k e :: cnstrs => processOffset { c with cnstrs } p k e
-      | .continue p :: cnstrs => processContinue { c with cnstrs } p
+    match c.cnstrs with
+    | [] => instantiateTheorem c
+    | .match p e :: cnstrs => processMatch { c with cnstrs } p e
+    | .continue p :: cnstrs => processContinue { c with cnstrs } p
+    processChoices
 
 private def main (p : Expr) (cnstrs : List Cnstr) : M Unit := do
   let some apps := (← getThe Goal).appMap.find? p.toHeadIndex
@@ -299,10 +227,9 @@ private def main (p : Expr) (cnstrs : List Cnstr) : M Unit := do
     let n ← getENode app
     if (n.heqProofs || n.isCongrRoot) &&
        (!useMT || n.mt == gmt) then
-      withInitApp app do
-        if let some c ← matchArgs? { cnstrs, assignment, gen := n.generation } p app |>.run then
-          modify fun s => { s with choiceStack := [c] }
-          processChoices
+      if let some c ← matchArgs? { cnstrs, assignment, gen := n.generation } p app |>.run then
+        modify fun s => { s with choiceStack := [c] }
+        processChoices
 
 def ematchTheorem (thm : EMatchTheorem) : M Unit := do
   if (← checkMaxInstancesExceeded) then return ()
@@ -341,7 +268,7 @@ def ematch : GoalM Unit := do
   let go (thms newThms : PArray EMatchTheorem) : EMatch.M Unit := do
     withReader (fun ctx => { ctx with useMT := true }) <| ematchTheorems thms
     withReader (fun ctx => { ctx with useMT := false }) <| ematchTheorems newThms
-  if (← checkMaxInstancesExceeded <||> checkMaxEmatchExceeded) then
+  if (← checkMaxInstancesExceeded) then
     return ()
   else
     go (← get).thms (← get).newThms |>.run'
@@ -349,18 +276,17 @@ def ematch : GoalM Unit := do
       thms         := s.thms ++ s.newThms
       newThms      := {}
       gmt          := s.gmt + 1
-      numEmatch    := s.numEmatch + 1
     }
 
 /-- Performs one round of E-matching, and assert new instances. -/
-def ematchAndAssert : GrindTactic := fun goal => do
+def ematchAndAssert? (goal : Goal) : GrindM (Option (List Goal)) := do
   let numInstances := goal.numInstances
   let goal ← GoalM.run' goal ematch
   if goal.numInstances == numInstances then
     return none
   assertAll goal
 
-def ematchStar : GrindTactic :=
-  ematchAndAssert.iterate
+def ematchStar (goal : Goal) : GrindM (List Goal) := do
+  iterate goal ematchAndAssert?
 
 end Lean.Meta.Grind

src/Lean/Meta/Tactic/Grind/EMatchTheorem.lean

@@ -4,49 +4,15 @@ Released under Apache 2.0 license as described in the file LICENSE.
 Authors: Leonardo de Moura
 -/
 prelude
-import Init.Grind.Util
-import Init.Grind.Tactics
 import Lean.HeadIndex
 import Lean.PrettyPrinter
 import Lean.Util.FoldConsts
 import Lean.Util.CollectFVars
 import Lean.Meta.Basic
 import Lean.Meta.InferType
-import Lean.Meta.Eqns
-import Lean.Meta.Tactic.Grind.Util
 
 namespace Lean.Meta.Grind
 
-def mkOffsetPattern (pat : Expr) (k : Nat) : Expr :=
-  mkApp2 (mkConst ``Grind.offset) pat (mkRawNatLit k)
-
-private def detectOffsets (pat : Expr) : MetaM Expr := do
-  let pre (e : Expr) := do
-    if e == pat then
-      -- We only consider nested offset patterns
-      return .continue e
-    else match e with
-      | .letE .. | .lam .. | .forallE .. => return .done e
-      | _ =>
-        let some (e, k) ← isOffset? e
-          | return .continue e
-        if k == 0 then return .continue e
-        return .continue <| mkOffsetPattern e k
-  Core.transform pat (pre := pre)
-
-def isOffsetPattern? (pat : Expr) : Option (Expr × Nat) := Id.run do
-  let_expr Grind.offset pat k := pat | none
-  let .lit (.natVal k) := k | none
-  return some (pat, k)
-
-def preprocessPattern (pat : Expr) (normalizePattern := true) : MetaM Expr := do
-  let pat ← instantiateMVars pat
-  let pat ← unfoldReducible pat
-  let pat ← if normalizePattern then normalize pat else pure pat
-  let pat ← detectOffsets pat
-  let pat ← foldProjs pat
-  return pat
-
 inductive Origin where
   /-- A global declaration in the environment. -/
   | decl (declName : Name)
@@ -57,29 +23,22 @@ inductive Origin where
   is the provided grind argument. The `id` is a unique identifier for the call.
   -/
   | stx (id : Name) (ref : Syntax)
-  /-- It is local, but we don't have a local hypothesis for it. -/
-  | local (id : Name)
-  deriving Inhabited, Repr, BEq
+  | other
+  deriving Inhabited, Repr
 
 /-- A unique identifier corresponding to the origin. -/
 def Origin.key : Origin → Name
   | .decl declName => declName
   | .fvar fvarId   => fvarId.name
   | .stx id _      => id
-  | .local id      => id
+  | .other         => `other
 
 def Origin.pp [Monad m] [MonadEnv m] [MonadError m] (o : Origin) : m MessageData := do
   match o with
   | .decl declName => return MessageData.ofConst (← mkConstWithLevelParams declName)
   | .fvar fvarId   => return mkFVar fvarId
   | .stx _ ref     => return ref
-  | .local id      => return id
-
-instance : BEq Origin where
-  beq a b := a.key == b.key
-
-instance : Hashable Origin where
-  hash a := hash a.key
+  | .other         => return "[unknown]"
 
 /-- A theorem for heuristic instantiation based on E-matching. -/
 structure EMatchTheorem where
@@ -97,58 +56,17 @@ structure EMatchTheorem where
   origin      : Origin
   deriving Inhabited
 
-/-- Set of E-matching theorems. -/
-structure EMatchTheorems where
-  /-- The key is a symbol from `EMatchTheorem.symbols`. -/
-  private map : PHashMap Name (List EMatchTheorem) := {}
-  /-- Set of theorem ids that have been inserted using `insert`. -/
-  private origins : PHashSet Origin := {}
-  /-- Theorems that have been marked as erased -/
-  private erased  : PHashSet Origin := {}
-  deriving Inhabited
+/-- The key is a symbol from `EMatchTheorem.symbols`. -/
+abbrev EMatchTheorems := PHashMap Name (List EMatchTheorem)
 
-/--
-Inserts a `thm` with symbols `[s_1, ..., s_n]` to `s`.
-We add `s_1 -> { thm with symbols := [s_2, ..., s_n] }`.
-When `grind` internalizes a term containing symbol `s`, we
-process all theorems `thm` associated with key `s`.
-If their `thm.symbols` is empty, we say they are activated.
-Otherwise, we reinsert into `map`.
--/
 def EMatchTheorems.insert (s : EMatchTheorems) (thm : EMatchTheorem) : EMatchTheorems := Id.run do
   let .const declName :: syms := thm.symbols
     | unreachable!
   let thm := { thm with symbols := syms }
-  let { map, origins, erased } := s
-  let origins := origins.insert thm.origin
-  let erased := erased.erase thm.origin
-  if let some thms := map.find? declName then
-    return { map := map.insert declName (thm::thms), origins, erased }
+  if let some thms := s.find? declName then
+    return PersistentHashMap.insert s declName (thm::thms)
   else
-    return { map := map.insert declName [thm], origins, erased }
-
-/-- Returns `true` if `s` contains a theorem with the given origin. -/
-def EMatchTheorems.contains (s : EMatchTheorems) (origin : Origin) : Bool :=
-  s.origins.contains origin
-
-/-- Mark the theorm with the given origin as `erased` -/
-def EMatchTheorems.erase (s : EMatchTheorems) (origin : Origin) : EMatchTheorems :=
-  { s with erased := s.erased.insert origin, origins := s.origins.erase origin }
-
-/-- Returns true if the theorem has been marked as erased. -/
-def EMatchTheorems.isErased (s : EMatchTheorems) (origin : Origin) : Bool :=
-  s.erased.contains origin
-
-/--
-Retrieves theorems from `s` associated with the given symbol. See `EMatchTheorem.insert`.
-The theorems are removed from `s`.
--/
-@[inline]
-def EMatchTheorems.retrieve? (s : EMatchTheorems) (sym : Name) : Option (List EMatchTheorem × EMatchTheorems) :=
-  if let some thms := s.map.find? sym then
-    some (thms, { s with map := s.map.erase sym })
-  else
-    none
+    return PersistentHashMap.insert s declName [thm]
 
 def EMatchTheorem.getProofWithFreshMVarLevels (thm : EMatchTheorem) : MetaM Expr := do
   if thm.proof.isConst && thm.levelParams.isEmpty then
@@ -167,46 +85,14 @@ def EMatchTheorem.getProofWithFreshMVarLevels (thm : EMatchTheorem) : MetaM Expr
 private builtin_initialize ematchTheoremsExt : SimpleScopedEnvExtension EMatchTheorem EMatchTheorems ←
   registerSimpleScopedEnvExtension {
     addEntry := EMatchTheorems.insert
-    initial  := {}
+    initial  := .empty
   }
 
-/--
-Symbols with built-in support in `grind` are unsuitable as pattern candidates for E-matching.
-This is because `grind` performs normalization operations and uses specialized data structures
-to implement these symbols, which may interfere with E-matching behavior.
--/
 -- TODO: create attribute?
 private def forbiddenDeclNames := #[``Eq, ``HEq, ``Iff, ``And, ``Or, ``Not]
 
 private def isForbidden (declName : Name) := forbiddenDeclNames.contains declName
 
-/--
-Auxiliary function to expand a pattern containing forbidden application symbols
-into a multi-pattern.
-
-This function enhances the usability of the `[grind =]` attribute by automatically handling
-forbidden pattern symbols. For example, consider the following theorem tagged with this attribute:
-```
-getLast?_eq_some_iff {xs : List α} {a : α} : xs.getLast? = some a ↔ ∃ ys, xs = ys ++ [a]
-```
-Here, the selected pattern is `xs.getLast? = some a`, but `Eq` is a forbidden pattern symbol.
-Instead of producing an error, this function converts the pattern into a multi-pattern,
-allowing the attribute to be used conveniently.
-
-The function recursively expands patterns with forbidden symbols by splitting them
-into their sub-components. If the pattern does not contain forbidden symbols,
-it is returned as-is.
--/
-partial def splitWhileForbidden (pat : Expr) : List Expr :=
-  match_expr pat with
-  | Not p => splitWhileForbidden p
-  | And p₁ p₂ => splitWhileForbidden p₁ ++ splitWhileForbidden p₂
-  | Or p₁ p₂ => splitWhileForbidden p₁ ++ splitWhileForbidden p₂
-  | Eq _ lhs rhs => splitWhileForbidden lhs ++ splitWhileForbidden rhs
-  | Iff lhs rhs => splitWhileForbidden lhs ++ splitWhileForbidden rhs
-  | HEq _ lhs _ rhs => splitWhileForbidden lhs ++ splitWhileForbidden rhs
-  | _ => [pat]
-
 private def dontCare := mkConst (Name.mkSimple "[grind_dontcare]")
 
 def mkGroundPattern (e : Expr) : Expr :=
@@ -268,19 +154,17 @@ private def getPatternFn? (pattern : Expr) : Option Expr :=
     | _ => none
 
 /--
-Returns a bit-mask `mask` s.t. `mask[i]` is true if the corresponding argument is
-- a type (that is not a proposition) or type former, or
+Returns a bit-mask `mask` s.t. `mask[i]` is true if the the corresponding argument is
+- a type or type former, or
 - a proof, or
 - an instance implicit argument
 
 When `mask[i]`, we say the corresponding argument is a "support" argument.
 -/
-def getPatternSupportMask (f : Expr) (numArgs : Nat) : MetaM (Array Bool) := do
+private def getPatternFunMask (f : Expr) (numArgs : Nat) : MetaM (Array Bool) := do
   forallBoundedTelescope (← inferType f) numArgs fun xs _ => do
     xs.mapM fun x => do
-      if (← isProp x) then
-        return false
-      else if (← isTypeFormer x <||> isProof x) then
+      if (← isTypeFormer x <||> isProof x) then
         return true
       else
         return (← x.fvarId!.getDecl).binderInfo matches .instImplicit
@@ -288,26 +172,16 @@ def getPatternSupportMask (f : Expr) (numArgs : Nat) : MetaM (Array Bool) := do
 private partial def go (pattern : Expr) (root := false) : M Expr := do
   if root && !pattern.hasLooseBVars then
     throwError "invalid pattern, it does not have pattern variables"
-  if let some (e, k) := isOffsetPattern? pattern then
-    let e ← goArg e (isSupport := false)
-    if e == dontCare then
-      return dontCare
-    else
-      return mkOffsetPattern e k
   let some f := getPatternFn? pattern
-    | throwError "invalid pattern, (non-forbidden) application expected{indentExpr pattern}"
+    | throwError "invalid pattern, (non-forbidden) application expected"
   assert! f.isConst || f.isFVar
   saveSymbol f.toHeadIndex
-  let mut args := pattern.getAppArgs.toVector
-  let supportMask ← getPatternSupportMask f args.size
-  for h : i in [:args.size] do
-    let arg := args[i]
+  let mut args := pattern.getAppArgs
+  let supportMask ← getPatternFunMask f args.size
+  for i in [:args.size] do
+    let arg := args[i]!
     let isSupport := supportMask[i]?.getD false
-    args := args.set i (← goArg arg isSupport)
-  return mkAppN f args.toArray
-where
-  goArg (arg : Expr) (isSupport : Bool) : M Expr := do
-    if !arg.hasLooseBVars then
+    let arg ← if !arg.hasLooseBVars then
       if arg.hasMVar then
         pure dontCare
       else
@@ -326,14 +200,13 @@ where
           go arg
         else
           pure dontCare
+    args := args.set! i arg
+  return mkAppN f args
 
 def main (patterns : List Expr) : MetaM (List Expr × List HeadIndex × Std.HashSet Nat) := do
   let (patterns, s) ← patterns.mapM go |>.run {}
   return (patterns, s.symbols.toList, s.bvarsFound)
 
-def normalizePattern (e : Expr) : M Expr := do
-  go e
-
 end NormalizePattern
 
 /--
@@ -447,8 +320,8 @@ private def checkCoverage (thmProof : Expr) (numParams : Nat) (bvarsFound : Std.
 Given a theorem with proof `proof` and `numParams` parameters, returns a message
 containing the parameters at positions `paramPos`.
 -/
-private def ppParamsAt (proof : Expr) (numParams : Nat) (paramPos : List Nat) : MetaM MessageData := do
-  forallBoundedTelescope (← inferType proof) numParams fun xs _ => do
+private def ppParamsAt (proof : Expr) (numParms : Nat) (paramPos : List Nat) : MetaM MessageData := do
+  forallBoundedTelescope (← inferType proof) numParms fun xs _ => do
     let mut msg := m!""
     let mut first := true
     for h : i in [:xs.size] do
@@ -458,301 +331,24 @@ private def ppParamsAt (proof : Expr) (numParams : Nat) (paramPos : List Nat) :
         msg := msg ++ m!"{x} : {← inferType x}"
     addMessageContextFull msg
 
-/--
-Creates an E-matching theorem for a theorem with proof `proof`, `numParams` parameters, and the given set of patterns.
-Pattern variables are represented using de Bruijn indices.
--/
-def mkEMatchTheoremCore (origin : Origin) (levelParams : Array Name) (numParams : Nat) (proof : Expr) (patterns : List Expr) : MetaM EMatchTheorem := do
+def addEMatchTheorem (declName : Name) (numParams : Nat) (patterns : List Expr) : MetaM Unit := do
+  let .thmInfo info ← getConstInfo declName
+    | throwError "`{declName}` is not a theorem, you cannot assign patterns to non-theorems for the `grind` tactic"
+  let us := info.levelParams.map mkLevelParam
+  let proof := mkConst declName us
   let (patterns, symbols, bvarFound) ← NormalizePattern.main patterns
-  trace[grind.ematch.pattern] "{MessageData.ofConst proof}: {patterns.map ppPattern}"
+  assert! symbols.all fun s => s matches .const _
+  trace[grind.ematch.pattern] "{declName}: {patterns.map ppPattern}"
   if let .missing pos ← checkCoverage proof numParams bvarFound then
      let pats : MessageData := m!"{patterns.map ppPattern}"
-     throwError "invalid pattern(s) for `{← origin.pp}`{indentD pats}\nthe following theorem parameters cannot be instantiated:{indentD (← ppParamsAt proof numParams pos)}"
-  return {
-    proof, patterns, numParams, symbols
-    levelParams, origin
+     throwError "invalid pattern(s) for `{declName}`{indentD pats}\nthe following theorem parameters cannot be instantiated:{indentD (← ppParamsAt proof numParams pos)}"
+  ematchTheoremsExt.add {
+     proof, patterns, numParams, symbols
+     levelParams := #[]
+     origin      := .decl declName
   }
 
-private def getProofFor (declName : Name) : CoreM Expr := do
-  let .thmInfo info ← getConstInfo declName
-    | throwError "`{declName}` is not a theorem"
-  let us := info.levelParams.map mkLevelParam
-  return mkConst declName us
-
-/--
-Creates an E-matching theorem for `declName` with `numParams` parameters, and the given set of patterns.
-Pattern variables are represented using de Bruijn indices.
--/
-def mkEMatchTheorem (declName : Name) (numParams : Nat) (patterns : List Expr) : MetaM EMatchTheorem := do
-  mkEMatchTheoremCore (.decl declName) #[] numParams (← getProofFor declName) patterns
-
-/--
-Given a theorem with proof `proof` and type of the form `∀ (a_1 ... a_n), lhs = rhs`,
-creates an E-matching pattern for it using `addEMatchTheorem n [lhs]`
-If `normalizePattern` is true, it applies the `grind` simplification theorems and simprocs to the pattern.
--/
-def mkEMatchEqTheoremCore (origin : Origin) (levelParams : Array Name) (proof : Expr) (normalizePattern : Bool) (useLhs : Bool) : MetaM EMatchTheorem := do
-  let (numParams, patterns) ← forallTelescopeReducing (← inferType proof) fun xs type => do
-    let (lhs, rhs) ← match_expr type with
-      | Eq _ lhs rhs => pure (lhs, rhs)
-      | Iff lhs rhs => pure (lhs, rhs)
-      | HEq _ lhs _ rhs => pure (lhs, rhs)
-      | _ => throwError "invalid E-matching equality theorem, conclusion must be an equality{indentExpr type}"
-    let pat := if useLhs then lhs else rhs
-    let pat ← preprocessPattern pat normalizePattern
-    let pats := splitWhileForbidden (pat.abstract xs)
-    return (xs.size, pats)
-  mkEMatchTheoremCore origin levelParams numParams proof patterns
-
-/--
-Given theorem with name `declName` and type of the form `∀ (a_1 ... a_n), lhs = rhs`,
-creates an E-matching pattern for it using `addEMatchTheorem n [lhs]`
-
-If `normalizePattern` is true, it applies the `grind` simplification theorems and simprocs to the
-pattern.
--/
-def mkEMatchEqTheorem (declName : Name) (normalizePattern := true) (useLhs : Bool := true) : MetaM EMatchTheorem := do
-  mkEMatchEqTheoremCore (.decl declName) #[] (← getProofFor declName) normalizePattern useLhs
-
-/--
-Adds an E-matching theorem to the environment.
-See `mkEMatchTheorem`.
--/
-def addEMatchTheorem (declName : Name) (numParams : Nat) (patterns : List Expr) : MetaM Unit := do
-  ematchTheoremsExt.add (← mkEMatchTheorem declName numParams patterns)
-
-/--
-Adds an E-matching equality theorem to the environment.
-See `mkEMatchEqTheorem`.
--/
-def addEMatchEqTheorem (declName : Name) : MetaM Unit := do
-  ematchTheoremsExt.add (← mkEMatchEqTheorem declName)
-
-/-- Returns the E-matching theorems registered in the environment. -/
 def getEMatchTheorems : CoreM EMatchTheorems :=
   return ematchTheoremsExt.getState (← getEnv)
 
-inductive TheoremKind where
-  | eqLhs | eqRhs | eqBoth | fwd | bwd | default
-  deriving Inhabited, BEq
-
-private def TheoremKind.toAttribute : TheoremKind → String
-  | .eqLhs   => "[grind =]"
-  | .eqRhs   => "[grind =_]"
-  | .eqBoth  => "[grind _=_]"
-  | .fwd     => "[grind →]"
-  | .bwd     => "[grind ←]"
-  | .default => "[grind]"
-
-private def TheoremKind.explainFailure : TheoremKind → String
-  | .eqLhs   => "failed to find pattern in the left-hand side of the theorem's conclusion"
-  | .eqRhs   => "failed to find pattern in the right-hand side of the theorem's conclusion"
-  | .eqBoth  => unreachable! -- eqBoth is a macro
-  | .fwd     => "failed to find patterns in the antecedents of the theorem"
-  | .bwd     => "failed to find patterns in the theorem's conclusion"
-  | .default => "failed to find patterns"
-
-/-- Returns the types of `xs` that are propositions. -/
-private def getPropTypes (xs : Array Expr) : MetaM (Array Expr) :=
-  xs.filterMapM fun x => do
-    let type ← inferType x
-    if (← isProp type) then return some type else return none
-
-/-- State for the (pattern) `CollectorM` monad -/
-private structure Collector.State where
-  /-- Pattern found so far. -/
-  patterns  : Array Expr := #[]
-  done      : Bool := false
-
-private structure Collector.Context where
-  proof : Expr
-  xs    : Array Expr
-
-/-- Monad for collecting patterns for a theorem. -/
-private abbrev CollectorM := ReaderT Collector.Context $ StateRefT Collector.State NormalizePattern.M
-
-/-- Similar to `getPatternFn?`, but operates on expressions that do not contain loose de Bruijn variables. -/
-private def isPatternFnCandidate (f : Expr) : CollectorM Bool := do
-  match f with
-  | .const declName _ => return !isForbidden declName
-  | .fvar .. => return !(← read).xs.contains f
-  | _ => return false
-
-private def addNewPattern (p : Expr) : CollectorM Unit := do
-  trace[grind.ematch.pattern.search] "found pattern: {ppPattern p}"
-  let bvarsFound := (← getThe NormalizePattern.State).bvarsFound
-  let done := (← checkCoverage (← read).proof (← read).xs.size bvarsFound) matches .ok
-  if done then
-    trace[grind.ematch.pattern.search] "found full coverage"
-  modify fun s => { s with patterns := s.patterns.push p, done }
-
-private partial def collect (e : Expr) : CollectorM Unit := do
-  if (← get).done then return ()
-  match e with
-  | .app .. =>
-    let f := e.getAppFn
-    if (← isPatternFnCandidate f) then
-      let saved ← getThe NormalizePattern.State
-      try
-        trace[grind.ematch.pattern.search] "candidate: {e}"
-        let p := e.abstract (← read).xs
-        unless p.hasLooseBVars do
-          trace[grind.ematch.pattern.search] "skip, does not contain pattern variables"
-          return ()
-        let p ← NormalizePattern.normalizePattern p
-        if saved.bvarsFound.size < (← getThe NormalizePattern.State).bvarsFound.size then
-          addNewPattern p
-          return ()
-        trace[grind.ematch.pattern.search] "skip, no new variables covered"
-        -- restore state and continue search
-        set saved
-      catch _ =>
-        trace[grind.ematch.pattern.search] "skip, exception during normalization"
-        -- restore state and continue search
-        set saved
-    let args := e.getAppArgs
-    for arg in args, flag in (← NormalizePattern.getPatternSupportMask f args.size) do
-      unless flag do
-        collect arg
-  | .forallE _ d b _ =>
-    if (← pure e.isArrow <&&> isProp d <&&> isProp b) then
-      collect d
-      collect b
-  | _ => return ()
-
-private def collectPatterns? (proof : Expr) (xs : Array Expr) (searchPlaces : Array Expr) : MetaM (Option (List Expr × List HeadIndex)) := do
-  let go : CollectorM (Option (List Expr)) := do
-    for place in searchPlaces do
-      let place ← preprocessPattern place
-      collect place
-      if (← get).done then
-        return some ((← get).patterns.toList)
-    return none
-  let (some ps, s) ← go { proof, xs } |>.run' {} |>.run {}
-    | return none
-  return some (ps, s.symbols.toList)
-
-def mkEMatchTheoremWithKind? (origin : Origin) (levelParams : Array Name) (proof : Expr) (kind : TheoremKind) : MetaM (Option EMatchTheorem) := do
-  if kind == .eqLhs then
-    return (← mkEMatchEqTheoremCore origin levelParams proof (normalizePattern := false) (useLhs := true))
-  else if kind == .eqRhs then
-    return (← mkEMatchEqTheoremCore origin levelParams proof (normalizePattern := false) (useLhs := false))
-  let type ← inferType proof
-  forallTelescopeReducing type fun xs type => do
-    let searchPlaces ← match kind with
-      | .fwd =>
-        let ps ← getPropTypes xs
-        if ps.isEmpty then
-          throwError "invalid `grind` forward theorem, theorem `{← origin.pp}` does not have propositional hypotheses"
-        pure ps
-      | .bwd => pure #[type]
-      | .default => pure <| #[type] ++ (← getPropTypes xs)
-      | _ => unreachable!
-    go xs searchPlaces
-where
-  go (xs : Array Expr) (searchPlaces : Array Expr) : MetaM (Option EMatchTheorem) := do
-    let some (patterns, symbols) ← collectPatterns? proof xs searchPlaces
-      | return none
-    let numParams := xs.size
-    trace[grind.ematch.pattern] "{← origin.pp}: {patterns.map ppPattern}"
-    return some {
-      proof, patterns, numParams, symbols
-      levelParams, origin
-    }
-
-private def getKind (stx : Syntax) : TheoremKind :=
-  if stx[1].isNone then
-    .default
-  else if stx[1][0].getKind == ``Parser.Attr.grindEq then
-    .eqLhs
-  else if stx[1][0].getKind == ``Parser.Attr.grindFwd then
-    .fwd
-  else if stx[1][0].getKind == ``Parser.Attr.grindEqRhs then
-    .eqRhs
-  else if stx[1][0].getKind == ``Parser.Attr.grindEqBoth then
-    .eqBoth
-  else
-    .bwd
-
-private def addGrindEqAttr (declName : Name) (attrKind : AttributeKind) (thmKind : TheoremKind) (useLhs := true) : MetaM Unit := do
-  if (← getConstInfo declName).isTheorem then
-    ematchTheoremsExt.add (← mkEMatchEqTheorem declName (normalizePattern := true) (useLhs := useLhs)) attrKind
-  else if let some eqns ← getEqnsFor? declName then
-    unless useLhs do
-      throwError "`{declName}` is a definition, you must only use the left-hand side for extracting patterns"
-    for eqn in eqns do
-      ematchTheoremsExt.add (← mkEMatchEqTheorem eqn) attrKind
-  else
-    throwError s!"`{thmKind.toAttribute}` attribute can only be applied to equational theorems or function definitions"
-
-private def addGrindAttr (declName : Name) (attrKind : AttributeKind) (thmKind : TheoremKind) : MetaM Unit := do
-  if thmKind == .eqLhs then
-    addGrindEqAttr declName attrKind thmKind (useLhs := true)
-  else if thmKind == .eqRhs then
-    addGrindEqAttr declName attrKind thmKind (useLhs := false)
-  else if thmKind == .eqBoth then
-    addGrindEqAttr declName attrKind thmKind (useLhs := true)
-    addGrindEqAttr declName attrKind thmKind (useLhs := false)
-  else if !(← getConstInfo declName).isTheorem then
-    addGrindEqAttr declName attrKind thmKind
-  else
-    let some thm ← mkEMatchTheoremWithKind? (.decl declName) #[] (← getProofFor declName) thmKind
-      | throwError "`@{thmKind.toAttribute} theorem {declName}` {thmKind.explainFailure}, consider using different options or the `grind_pattern` command"
-    ematchTheoremsExt.add thm attrKind
-
-builtin_initialize
-  registerBuiltinAttribute {
-    name := `grind
-    descr :=
-      "The `[grind]` attribute is used to annotate declarations.\
-      \
-      When applied to an equational theorem, `[grind =]`, `[grind =_]`, or `[grind _=_]`\
-      will mark the theorem for use in heuristic instantiations by the `grind` tactic,
-      using respectively the left-hand side, the right-hand side, or both sides of the theorem.\
-      When applied to a function, `[grind =]` automatically annotates the equational theorems associated with that function.\
-      When applied to a theorem `[grind ←]` will instantiate the theorem whenever it encounters the conclusion of the theorem
-      (that is, it will use the theorem for backwards reasoning).\
-      When applied to a theorem `[grind →]` will instantiate the theorem whenever it encounters sufficiently many of the propositional hypotheses
-      (that is, it will use the theorem for forwards reasoning).\
-      \
-      The attribute `[grind]` by itself will effectively try `[grind ←]` (if the conclusion is sufficient for instantiation) and then `[grind →]`.\
-      \
-      The `grind` tactic utilizes annotated theorems to add instances of matching patterns into the local context during proof search.\
-      For example, if a theorem `@[grind =] theorem foo_idempotent : foo (foo x) = foo x` is annotated,\
-      `grind` will add an instance of this theorem to the local context whenever it encounters the pattern `foo (foo x)`."
-    applicationTime := .afterCompilation
-    add := fun declName stx attrKind => do
-      addGrindAttr declName attrKind (getKind stx) |>.run' {}
-    erase := fun declName => MetaM.run' do
-      /-
-      Remark: consider the following example
-      ```
-      attribute [grind] foo  -- ok
-      attribute [-grind] foo.eqn_2  -- ok
-      attribute [-grind] foo  -- error
-      ```
-      One may argue that the correct behavior should be
-      ```
-      attribute [grind] foo  -- ok
-      attribute [-grind] foo.eqn_2  -- error
-      attribute [-grind] foo  -- ok
-      ```
-      -/
-      let throwErr := throwError "`{declName}` is not marked with the `[grind]` attribute"
-      let info ← getConstInfo declName
-      if !info.isTheorem then
-        if let some eqns ← getEqnsFor? declName then
-           let s := ematchTheoremsExt.getState (← getEnv)
-           unless eqns.all fun eqn => s.contains (.decl eqn) do
-             throwErr
-           modifyEnv fun env => ematchTheoremsExt.modifyState env fun s =>
-             eqns.foldl (init := s) fun s eqn => s.erase (.decl eqn)
-        else
-          throwErr
-      else
-        unless ematchTheoremsExt.getState (← getEnv) |>.contains (.decl declName) do
-          throwErr
-        modifyEnv fun env => ematchTheoremsExt.modifyState env fun s => s.erase (.decl declName)
-  }
-
 end Lean.Meta.Grind

src/Lean/Meta/Tactic/Grind/ENodeKey.lean

@@ -1,30 +0,0 @@
-/-
-Copyright (c) 2025 Amazon.com, Inc. or its affiliates. All Rights Reserved.
-Released under Apache 2.0 license as described in the file LICENSE.
-Authors: Leonardo de Moura
--/
-prelude
-import Lean.Expr
-
-namespace Lean.Meta.Grind
-
-@[inline] def isSameExpr (a b : Expr) : Bool :=
-  -- It is safe to use pointer equality because we hashcons all expressions
-  -- inserted into the E-graph
-  unsafe ptrEq a b
-
-/--
-Key for the `ENodeMap` and `ParentMap` map.
-We use pointer addresses and rely on the fact all internalized expressions
-have been hash-consed, i.e., we have applied `shareCommon`.
--/
-structure ENodeKey where
-  expr : Expr
-
-instance : Hashable ENodeKey where
-  hash k := unsafe (ptrAddrUnsafe k.expr).toUInt64
-
-instance : BEq ENodeKey where
-  beq k₁ k₂ := isSameExpr k₁.expr k₂.expr
-
-end Lean.Meta.Grind

src/Lean/Meta/Tactic/Grind/ForallProp.lean

@@ -15,88 +15,17 @@ If `parent` is a projection-application `proj_i c`,
 check whether the root of the equivalence class containing `c` is a constructor-application `ctor ... a_i ...`.
 If so, internalize the term `proj_i (ctor ... a_i ...)` and add the equality `proj_i (ctor ... a_i ...) = a_i`.
 -/
-def propagateForallPropUp (e : Expr) : GoalM Unit := do
-  let .forallE n p q bi := e | return ()
-  trace_goal[grind.debug.forallPropagator] "{e}"
-  if !q.hasLooseBVars then
-    propagateImpliesUp p q
-  else
-    unless (← isEqTrue p) do return
-    trace_goal[grind.debug.forallPropagator] "isEqTrue, {e}"
-    let h₁ ← mkEqTrueProof p
-    let qh₁ := q.instantiate1 (mkOfEqTrueCore p h₁)
-    let r ← simp qh₁
-    let q := mkLambda n bi p q
-    let q' := r.expr
-    internalize q' (← getGeneration e)
-    trace_goal[grind.debug.forallPropagator] "q': {q'} for{indentExpr e}"
-    let h₂ ← r.getProof
-    let h := mkApp5 (mkConst ``Lean.Grind.forall_propagator) p q q' h₁ h₂
-    pushEq e q' h
-where
-  propagateImpliesUp (a b : Expr) : GoalM Unit := do
-    unless (← alreadyInternalized b) do return ()
-    if (← isEqFalse a) then
-      -- a = False → (a → b) = True
-      pushEqTrue e <| mkApp3 (mkConst ``Grind.imp_eq_of_eq_false_left) a b (← mkEqFalseProof a)
-    else if (← isEqTrue a) then
-      -- a = True → (a → b) = b
-      pushEq e b <| mkApp3 (mkConst ``Grind.imp_eq_of_eq_true_left) a b (← mkEqTrueProof a)
-    else if (← isEqTrue b) then
-      -- b = True → (a → b) = True
-      pushEqTrue e <| mkApp3 (mkConst ``Grind.imp_eq_of_eq_true_right) a b (← mkEqTrueProof b)
-
-private def isEqTrueHyp? (proof : Expr) : Option FVarId := Id.run do
-  let_expr eq_true _ p := proof | return none
-  let .fvar fvarId := p | return none
-  return some fvarId
-
-/-- Similar to `mkEMatchTheoremWithKind?`, but swallow any exceptions. -/
-private def mkEMatchTheoremWithKind'? (origin : Origin) (proof : Expr) (kind : TheoremKind) : MetaM (Option EMatchTheorem) := do
-  try
-    mkEMatchTheoremWithKind? origin #[] proof kind
-  catch _ =>
-    return none
-
-private def addLocalEMatchTheorems (e : Expr) : GoalM Unit := do
-  let proof ← mkEqTrueProof e
-  let origin ← if let some fvarId := isEqTrueHyp? proof then
-    pure <| .fvar fvarId
-  else
-    let idx ← modifyGet fun s => (s.nextThmIdx, { s with nextThmIdx := s.nextThmIdx + 1 })
-    pure <| .local ((`local).appendIndexAfter idx)
-  let proof := mkOfEqTrueCore e proof
-  let size := (← get).newThms.size
-  let gen ← getGeneration e
-  -- TODO: we should have a flag for collecting all unary patterns in a local theorem
-  if let some thm ← mkEMatchTheoremWithKind'? origin proof .fwd then
-    activateTheorem thm gen
-  if let some thm ← mkEMatchTheoremWithKind'? origin proof .bwd then
-    activateTheorem thm gen
-  if (← get).newThms.size == size then
-    if let some thm ← mkEMatchTheoremWithKind'? origin proof .default then
-      activateTheorem thm gen
-  if (← get).newThms.size == size then
-    trace[grind.issues] "failed to create E-match local theorem for{indentExpr e}"
-
-def propagateForallPropDown (e : Expr) : GoalM Unit := do
-  let .forallE n a b bi := e | return ()
-  if (← isEqFalse e) then
-    if b.hasLooseBVars then
-      let α := a
-      let p := b
-      -- `e` is of the form `∀ x : α, p x`
-      -- Add fact `∃ x : α, ¬ p x`
-      let u ← getLevel α
-      let prop := mkApp2 (mkConst ``Exists [u]) α (mkLambda n bi α (mkNot p))
-      let proof := mkApp3 (mkConst ``Grind.of_forall_eq_false [u]) α (mkLambda n bi α p) (← mkEqFalseProof e)
-      addNewFact proof prop (← getGeneration e)
-    else
-      let h ← mkEqFalseProof e
-      pushEqTrue a <| mkApp3 (mkConst ``Grind.eq_true_of_imp_eq_false) a b h
-      pushEqFalse b <| mkApp3 (mkConst ``Grind.eq_false_of_imp_eq_false) a b h
-  else if (← isEqTrue e) then
-    if b.hasLooseBVars then
-      addLocalEMatchTheorems e
+def propagateForallProp (parent : Expr) : GoalM Unit := do
+  let .forallE n p q bi := parent | return ()
+  unless (← isEqTrue p) do return ()
+  let h₁ ← mkEqTrueProof p
+  let qh₁ := q.instantiate1 (mkApp2 (mkConst ``of_eq_true) p h₁)
+  let r ← simp qh₁
+  let q := mkLambda n bi p q
+  let q' := r.expr
+  internalize q' (← getGeneration parent)
+  let h₂ ← r.getProof
+  let h := mkApp5 (mkConst ``Lean.Grind.forall_propagator) p q q' h₁ h₂
+  pushEq parent q' h
 
 end Lean.Meta.Grind

src/Lean/Meta/Tactic/Grind/Internalize.lean

@@ -5,13 +5,9 @@ Authors: Leonardo de Moura
 -/
 prelude
 import Init.Grind.Util
-import Init.Grind.Lemmas
 import Lean.Meta.LitValues
-import Lean.Meta.Match.MatcherInfo
-import Lean.Meta.Match.MatchEqsExt
 import Lean.Meta.Tactic.Grind.Types
 import Lean.Meta.Tactic.Grind.Util
-import Lean.Meta.Tactic.Grind.Arith.Internalize
 
 namespace Lean.Meta.Grind
 
@@ -24,19 +20,15 @@ def addCongrTable (e : Expr) : GoalM Unit := do
     let g := e'.getAppFn
     unless isSameExpr f g do
       unless (← hasSameType f g) do
-        trace_goal[grind.issues] "found congruence between{indentExpr e}\nand{indentExpr e'}\nbut functions have different types"
+        trace[grind.issues] "found congruence between{indentExpr e}\nand{indentExpr e'}\nbut functions have different types"
         return ()
-    trace_goal[grind.debug.congr] "{e} = {e'}"
+    trace[grind.debug.congr] "{e} = {e'}"
     pushEqHEq e e' congrPlaceholderProof
     let node ← getENode e
     setENode e { node with congr := e' }
   else
     modify fun s => { s with congrTable := s.congrTable.insert { e } }
 
-/--
-Given an application `e` of the form `f a_1 ... a_n`,
-adds entry `f ↦ e` to `appMap`. Recall that `appMap` is a multi-map.
--/
 private def updateAppMap (e : Expr) : GoalM Unit := do
   let key := e.toHeadIndex
   modify fun s => { s with
@@ -46,58 +38,6 @@ private def updateAppMap (e : Expr) : GoalM Unit := do
       s.appMap.insert key [e]
   }
 
-/-- Inserts `e` into the list of case-split candidates. -/
-private def addSplitCandidate (e : Expr) : GoalM Unit := do
-  trace_goal[grind.split.candidate] "{e}"
-  modify fun s => { s with splitCandidates := e :: s.splitCandidates }
-
--- TODO: add attribute to make this extensible
-private def forbiddenSplitTypes := [``Eq, ``HEq, ``True, ``False]
-
-/-- Returns `true` if `e` is of the form `@Eq Prop a b` -/
-def isMorallyIff (e : Expr) : Bool :=
-  let_expr Eq α _ _ := e | false
-  α.isProp
-
-/-- Inserts `e` into the list of case-split candidates if applicable. -/
-private def checkAndAddSplitCandidate (e : Expr) : GoalM Unit := do
-  unless e.isApp do return ()
-  if (← getConfig).splitIte && (e.isIte || e.isDIte) then
-    addSplitCandidate e
-    return ()
-  if isMorallyIff e then
-    addSplitCandidate e
-    return ()
-  if (← getConfig).splitMatch then
-    if (← isMatcherApp e) then
-      if let .reduced _ ← reduceMatcher? e then
-        -- When instantiating `match`-equations, we add `match`-applications that can be reduced,
-        -- and consequently don't need to be splitted.
-        return ()
-      else
-        addSplitCandidate e
-        return ()
-  let .const declName _  := e.getAppFn | return ()
-    if forbiddenSplitTypes.contains declName then return ()
-    -- We should have a mechanism for letting users to select types to case-split.
-    -- Right now, we just consider inductive predicates that are not in the forbidden list
-    if (← getConfig).splitIndPred then
-      if (← isInductivePredicate declName) then
-        addSplitCandidate e
-
-/--
-If `e` is a `cast`-like term (e.g., `cast h a`), add `HEq e a` to the to-do list.
-It could be an E-matching theorem, but we want to ensure it is always applied since
-we want to rely on the fact that `cast h a` and `a` are in the same equivalence class.
--/
-private def pushCastHEqs (e : Expr) : GoalM Unit := do
-  match_expr e with
-  | f@cast α β h a => pushHEq e a (mkApp4 (mkConst ``cast_heq f.constLevels!) α β h a)
-  | f@Eq.rec α a motive v b h => pushHEq e v (mkApp6 (mkConst ``Grind.eqRec_heq f.constLevels!) α a motive v b h)
-  | f@Eq.ndrec α a motive v b h => pushHEq e v (mkApp6 (mkConst ``Grind.eqNDRec_heq f.constLevels!) α a motive v b h)
-  | f@Eq.recOn α a motive b h v => pushHEq e v (mkApp6 (mkConst ``Grind.eqRecOn_heq f.constLevels!) α a motive b h v)
-  | _ => return ()
-
 mutual
 /-- Internalizes the nested ground terms in the given pattern. -/
 private partial def internalizePattern (pattern : Expr) (generation : Nat) : GoalM Expr := do
@@ -110,74 +50,51 @@ private partial def internalizePattern (pattern : Expr) (generation : Nat) : Goa
   else pattern.withApp fun f args => do
     return mkAppN f (← args.mapM (internalizePattern · generation))
 
-partial def activateTheorem (thm : EMatchTheorem) (generation : Nat) : GoalM Unit := do
-  -- Recall that we use the proof as part of the key for a set of instances found so far.
-  -- We don't want to use structural equality when comparing keys.
-  let proof ← shareCommon thm.proof
-  let thm := { thm with proof, patterns := (← thm.patterns.mapM (internalizePattern · generation)) }
-  trace_goal[grind.ematch] "activated `{thm.origin.key}`, {thm.patterns.map ppPattern}"
-  modify fun s => { s with newThms := s.newThms.push thm }
-
-/--
-If `Config.matchEqs` is set to `true`, and `f` is `match`-auxiliary function,
-adds its equations to `newThms`.
--/
-private partial def addMatchEqns (f : Expr) (generation : Nat) : GoalM Unit := do
-  if !(← getConfig).matchEqs then return ()
-  let .const declName _ := f | return ()
-  if !(← isMatcher declName) then return ()
-  if (← get).matchEqNames.contains declName then return ()
-  modify fun s => { s with matchEqNames := s.matchEqNames.insert declName }
-  for eqn in (← Match.getEquationsFor declName).eqnNames do
-    -- We disable pattern normalization to prevent the `match`-expression to be reduced.
-    activateTheorem (← mkEMatchEqTheorem eqn (normalizePattern := false)) generation
-
 private partial def activateTheoremPatterns (fName : Name) (generation : Nat) : GoalM Unit := do
-  if let some (thms, thmMap) := (← get).thmMap.retrieve? fName then
-    modify fun s => { s with thmMap }
+  if let some thms := (← get).thmMap.find? fName then
+    modify fun s => { s with thmMap := s.thmMap.erase fName }
     let appMap := (← get).appMap
     for thm in thms do
-      unless (← get).thmMap.isErased thm.origin do
-        let symbols := thm.symbols.filter fun sym => !appMap.contains sym
-        let thm := { thm with symbols }
-        match symbols with
-        | [] => activateTheorem thm generation
-        | _ =>
-          trace_goal[grind.ematch] "reinsert `{thm.origin.key}`"
-          modify fun s => { s with thmMap := s.thmMap.insert thm }
+      let symbols := thm.symbols.filter fun sym => !appMap.contains sym
+      let thm := { thm with symbols }
+      match symbols with
+      | [] =>
+        -- Recall that we use the proof as part of the key for a set of instances found so far.
+        -- We don't want to use structural equality when comparing keys.
+        let proof ← shareCommon thm.proof
+        let thm := { thm with proof, patterns := (← thm.patterns.mapM (internalizePattern · generation)) }
+        trace[grind.ematch] "activated `{thm.origin.key}`, {thm.patterns.map ppPattern}"
+        modify fun s => { s with newThms := s.newThms.push thm }
+      | _ =>
+        trace[grind.ematch] "reinsert `{thm.origin.key}`"
+        modify fun s => { s with thmMap := s.thmMap.insert thm }
 
 partial def internalize (e : Expr) (generation : Nat) : GoalM Unit := do
   if (← alreadyInternalized e) then return ()
-  trace_goal[grind.internalize] "{e}"
+  trace[grind.internalize] "{e}"
   match e with
   | .bvar .. => unreachable!
   | .sort .. => return ()
   | .fvar .. | .letE .. | .lam .. =>
     mkENodeCore e (ctor := false) (interpreted := false) (generation := generation)
-  | .forallE _ d b _ =>
+  | .forallE _ d _ _ =>
     mkENodeCore e (ctor := false) (interpreted := false) (generation := generation)
     if (← isProp d <&&> isProp e) then
       internalize d generation
       registerParent e d
-      unless b.hasLooseBVars do
-        internalize b generation
-        registerParent e b
       propagateUp e
   | .lit .. | .const .. =>
     mkENode e generation
   | .mvar ..
   | .mdata ..
   | .proj .. =>
-    trace_goal[grind.issues] "unexpected term during internalization{indentExpr e}"
+    trace[grind.issues] "unexpected term during internalization{indentExpr e}"
     mkENodeCore e (ctor := false) (interpreted := false) (generation := generation)
   | .app .. =>
     if (← isLitValue e) then
       -- We do not want to internalize the components of a literal value.
       mkENode e generation
     else e.withApp fun f args => do
-      checkAndAddSplitCandidate e
-      pushCastHEqs e
-      addMatchEqns f generation
       if f.isConstOf ``Lean.Grind.nestedProof && args.size == 2 then
         -- We only internalize the proposition. We can skip the proof because of
         -- proof irrelevance
@@ -197,7 +114,6 @@ partial def internalize (e : Expr) (generation : Nat) : GoalM Unit := do
       mkENode e generation
       addCongrTable e
       updateAppMap e
-      Arith.internalize e
       propagateUp e
 end
 

src/Lean/Meta/Tactic/Grind/Intro.lean

@@ -11,7 +11,6 @@ import Lean.Meta.Tactic.Grind.Types
 import Lean.Meta.Tactic.Grind.Cases
 import Lean.Meta.Tactic.Grind.Injection
 import Lean.Meta.Tactic.Grind.Core
-import Lean.Meta.Tactic.Grind.Combinators
 
 namespace Lean.Meta.Grind
 
@@ -22,7 +21,7 @@ private inductive IntroResult where
   | newLocal (fvarId : FVarId) (goal : Goal)
   deriving Inhabited
 
-private def introNext (goal : Goal) (generation : Nat) : GrindM IntroResult := do
+private def introNext (goal : Goal) : GrindM IntroResult := do
   let target ← goal.mvarId.getType
   if target.isArrow then
     goal.mvarId.withContext do
@@ -50,7 +49,7 @@ private def introNext (goal : Goal) (generation : Nat) : GrindM IntroResult := d
             -- `p` and `p'` are definitionally equal
             goal.mvarId.assign h
             return .newHyp fvarId { goal with mvarId := mvarIdNew }
-  else if target.isLet || target.isForall || target.isLetFun then
+  else if target.isLet || target.isForall then
     let (fvarId, mvarId) ← goal.mvarId.intro1P
     mvarId.withContext do
       let localDecl ← fvarId.getDecl
@@ -59,25 +58,17 @@ private def introNext (goal : Goal) (generation : Nat) : GrindM IntroResult := d
         let mvarId ← mvarId.assert (← mkFreshUserName localDecl.userName) localDecl.type (mkFVar fvarId)
         return .newDepHyp { goal with mvarId }
       else
-        let goal := { goal with mvarId }
-        if target.isLet || target.isLetFun then
-          let v := (← fvarId.getDecl).value
-          let r ← simp v
-          let x ← shareCommon (mkFVar fvarId)
-          let goal ← GoalM.run' goal <| addNewEq x r.expr (← r.getProof) generation
-          return .newLocal fvarId goal
-        else
-          return .newLocal fvarId goal
+        return .newLocal fvarId { goal with mvarId }
   else
     return .done
 
-private def isCasesCandidate (type : Expr) : MetaM Bool := do
-  let .const declName _ := type.getAppFn | return false
+private def isCasesCandidate (fvarId : FVarId) : MetaM Bool := do
+  let .const declName _ := (← fvarId.getType).getAppFn | return false
   isGrindCasesTarget declName
 
 private def applyCases? (goal : Goal) (fvarId : FVarId) : MetaM (Option (List Goal)) := goal.mvarId.withContext do
-  if (← isCasesCandidate (← fvarId.getType)) then
-    let mvarIds ← cases goal.mvarId (mkFVar fvarId)
+  if (← isCasesCandidate fvarId) then
+    let mvarIds ← cases goal.mvarId fvarId
     return mvarIds.map fun mvarId => { goal with mvarId }
   else
     return none
@@ -89,11 +80,11 @@ private def applyInjection? (goal : Goal) (fvarId : FVarId) : MetaM (Option Goal
     return none
 
 /-- Introduce new hypotheses (and apply `by_contra`) until goal is of the form `... ⊢ False` -/
-partial def intros  (generation : Nat) : GrindTactic' := fun goal => do
+partial def intros (goal : Goal) (generation : Nat) : GrindM (List Goal) := do
   let rec go (goal : Goal) : StateRefT (Array Goal) GrindM Unit := do
     if goal.inconsistent then
       return ()
-    match (← introNext goal generation) with
+    match (← introNext goal) with
     | .done =>
       if let some mvarId ← goal.mvarId.byContra? then
         go { goal with mvarId }
@@ -117,27 +108,32 @@ partial def intros  (generation : Nat) : GrindTactic' := fun goal => do
   return goals.toList
 
 /-- Asserts a new fact `prop` with proof `proof` to the given `goal`. -/
-def assertAt (proof : Expr) (prop : Expr) (generation : Nat) : GrindTactic' := fun goal => do
-  if (← isCasesCandidate prop) then
-    let mvarId ← goal.mvarId.assert (← mkFreshUserName `h) prop proof
-    let goal := { goal with mvarId }
-    intros generation goal
-  else
-    let goal ← GoalM.run' goal do
-      let r ← simp prop
-      let prop' := r.expr
-      let proof' ← mkEqMP (← r.getProof) proof
-      add prop' proof' generation
-    if goal.inconsistent then return [] else return [goal]
+def assertAt (goal : Goal) (proof : Expr) (prop : Expr) (generation : Nat) : GrindM (List Goal) := do
+  -- TODO: check whether `prop` may benefit from `intros` or not. If not, we should avoid the `assert`+`intros` step and use `Grind.add`
+  let mvarId ← goal.mvarId.assert (← mkFreshUserName `h) prop proof
+  let goal := { goal with mvarId }
+  intros goal generation
 
 /-- Asserts next fact in the `goal` fact queue. -/
-def assertNext : GrindTactic := fun goal => do
+def assertNext? (goal : Goal) : GrindM (Option (List Goal)) := do
   let some (fact, newFacts) := goal.newFacts.dequeue?
     | return none
-  assertAt fact.proof fact.prop fact.generation { goal with newFacts }
+  assertAt { goal with newFacts } fact.proof fact.prop fact.generation
+
+partial def iterate (goal : Goal) (f : Goal → GrindM (Option (List Goal))) : GrindM (List Goal) := do
+  go [goal] []
+where
+  go (todo : List Goal) (result : List Goal) : GrindM (List Goal) := do
+    match todo with
+    | [] => return result
+    | goal :: todo =>
+      if let some goalsNew ← f goal then
+        go (goalsNew ++ todo) result
+      else
+        go todo (goal :: result)
 
 /-- Asserts all facts in the `goal` fact queue. -/
-partial def assertAll : GrindTactic :=
-  assertNext.iterate
+partial def assertAll (goal : Goal) : GrindM (List Goal) := do
+  iterate goal assertNext?
 
 end Lean.Meta.Grind

src/Lean/Meta/Tactic/Grind/Inv.lean

@@ -6,7 +6,6 @@ Authors: Leonardo de Moura
 prelude
 import Lean.Meta.Tactic.Grind.Types
 import Lean.Meta.Tactic.Grind.Proof
-import Lean.Meta.Tactic.Grind.Arith.Inv
 
 namespace Lean.Meta.Grind
 
@@ -59,12 +58,9 @@ private def checkParents (e : Expr) : GoalM Unit := do
           found := true
           break
       -- Recall that we have support for `Expr.forallE` propagation. See `ForallProp.lean`.
-      if let .forallE _ d b _ := parent then
+      if let .forallE _ d _ _ := parent then
         if (← checkChild d) then
           found := true
-        unless b.hasLooseBVars do
-          if (← checkChild b) then
-            found := true
       unless found do
         assert! (← checkChild parent.getAppFn)
   else
@@ -89,9 +85,9 @@ private def checkProofs : GoalM Unit := do
       for b in eqc do
         unless isSameExpr a b do
           let p ← mkEqHEqProof a b
-          trace_goal[grind.debug.proofs] "{a} = {b}"
+          trace[grind.debug.proofs] "{a} = {b}"
           check p
-          trace_goal[grind.debug.proofs] "checked: {← inferType p}"
+          trace[grind.debug.proofs] "checked: {← inferType p}"
 
 /--
 Checks basic invariants if `grind.debug` is enabled.
@@ -104,7 +100,6 @@ def checkInvariants (expensive := false) : GoalM Unit := do
         checkEqc node
     if expensive then
       checkPtrEqImpliesStructEq
-    Arith.checkInvariants
   if expensive && grind.debug.proofs.get (← getOptions) then
     checkProofs
 

src/Lean/Meta/Tactic/Grind/Main.lean

@@ -14,8 +14,6 @@ import Lean.Meta.Tactic.Grind.Util
 import Lean.Meta.Tactic.Grind.Inv
 import Lean.Meta.Tactic.Grind.Intro
 import Lean.Meta.Tactic.Grind.EMatch
-import Lean.Meta.Tactic.Grind.Split
-import Lean.Meta.Tactic.Grind.SimpUtil
 
 namespace Lean.Meta.Grind
 
@@ -24,13 +22,12 @@ def mkMethods (fallback : Fallback) : CoreM Methods := do
   return {
     fallback
     propagateUp := fun e => do
-     propagateForallPropUp e
+     propagateForallProp e
      let .const declName _ := e.getAppFn | return ()
      propagateProjEq e
      if let some prop := builtinPropagators.up[declName]? then
        prop e
     propagateDown := fun e => do
-     propagateForallPropDown e
      let .const declName _ := e.getAppFn | return ()
      if let some prop := builtinPropagators.down[declName]? then
        prop e
@@ -40,8 +37,12 @@ def GrindM.run (x : GrindM α) (mainDeclName : Name) (config : Grind.Config) (fa
   let scState := ShareCommon.State.mk _
   let (falseExpr, scState) := ShareCommon.State.shareCommon scState (mkConst ``False)
   let (trueExpr, scState)  := ShareCommon.State.shareCommon scState (mkConst ``True)
-  let simprocs ← Grind.getSimprocs
-  let simp ← Grind.getSimpContext
+  let thms ← grindNormExt.getTheorems
+  let simprocs := #[(← grindNormSimprocExt.getSimprocs)]
+  let simp ← Simp.mkContext
+    (config := { arith := true })
+    (simpTheorems := #[thms])
+    (congrTheorems := (← getSimpCongrTheorems))
   x (← mkMethods fallback).toMethodsRef { mainDeclName, config, simprocs, simp } |>.run' { scState, trueExpr, falseExpr }
 
 private def mkGoal (mvarId : MVarId) : GrindM Goal := do
@@ -60,7 +61,6 @@ private def initCore (mvarId : MVarId) : GrindM (List Goal) := do
   let mvarId ← mvarId.revertAll
   let mvarId ← mvarId.unfoldReducible
   let mvarId ← mvarId.betaReduce
-  appendTagSuffix mvarId `grind
   let goals ← intros (← mkGoal mvarId) (generation := 0)
   goals.forM (·.checkInvariants (expensive := true))
   return goals.filter fun goal => !goal.inconsistent
@@ -70,10 +70,10 @@ def all (goals : List Goal) (f : Goal → GrindM (List Goal)) : GrindM (List Goa
 
 /-- A very simple strategy -/
 private def simple (goals : List Goal) : GrindM (List Goal) := do
-  applyToAll (assertAll >> ematchStar >> (splitNext >> assertAll >> ematchStar).iterate) goals
+  all goals ematchStar
 
-def main (mvarId : MVarId) (config : Grind.Config) (mainDeclName : Name) (fallback : Fallback) : MetaM (List Goal) := do
-  let go : GrindM (List Goal) := do
+def main (mvarId : MVarId) (config : Grind.Config) (mainDeclName : Name) (fallback : Fallback) : MetaM (List MVarId) := do
+  let go : GrindM (List MVarId) := do
     let goals ← initCore mvarId
     let goals ← simple goals
     let goals ← goals.filterMapM fun goal => do
@@ -83,7 +83,7 @@ def main (mvarId : MVarId) (config : Grind.Config) (mainDeclName : Name) (fallba
       if (← goal.mvarId.isAssigned) then return none
       return some goal
     trace[grind.debug.final] "{← ppGoals goals}"
-    return goals
+    return goals.map (·.mvarId)
   go.run mainDeclName config fallback
 
 end Lean.Meta.Grind

src/Lean/Meta/Tactic/Grind/MarkNestedProofs.lean

@@ -24,37 +24,30 @@ where
       let e' := mkApp2 (mkConst ``Lean.Grind.nestedProof) prop e
       modify fun s => s.insert e e'
       return e'
-    -- Remark: we have to process `Expr.proj` since we only
-    -- fold projections later during term internalization
-    unless e.isApp || e.isForall || e.isProj do
-      return e
-    -- Check whether it is cached
-    if let some r := (← get).find? e then
-      return r
-    let e' ← match e with
-      | .app .. => e.withApp fun f args => do
-        let mut modified := false
-        let mut args := args
-        for i in [:args.size] do
-          let arg := args[i]!
-          let arg' ← visit arg
-          unless ptrEq arg arg' do
-            args := args.set! i arg'
-            modified := true
-        if modified then
-          pure <| mkAppN f args
-        else
-          pure e
-      | .proj _ _ b =>
-        pure <| e.updateProj! (← visit b)
-      | .forallE _ d b _ =>
-        -- Recall that we have `ForallProp.lean`.
-        let d' ← visit d
-        let b' ← if b.hasLooseBVars then pure b else visit b
-        pure <| e.updateForallE! d' b'
-      | _ => unreachable!
-    modify fun s => s.insert e e'
-    return e'
+    else match e with
+      | .bvar .. => unreachable!
+      -- See comments on `Canon.lean` for why we do not visit these cases.
+      | .letE .. | .forallE .. | .lam ..
+      | .const .. | .lit .. | .mvar .. | .sort .. | .fvar .. => return e
+      | .proj _ _ b => return e.updateProj! (← visit b)
+      | .mdata _ b  => return e.updateMData! (← visit b)
+      -- We only visit applications
+      | .app .. =>
+        -- Check whether it is cached
+        if let some r := (← get).find? e then
+          return r
+        e.withApp fun f args => do
+          let mut modified := false
+          let mut args := args
+          for i in [:args.size] do
+            let arg := args[i]!
+            let arg' ← visit arg
+            unless ptrEq arg arg' do
+              args := args.set! i arg'
+              modified := true
+          let e' := if modified then mkAppN f args else e
+          modify fun s => s.insert e e'
+          return e'
 
 /--
 Wrap nested proofs `e` with `Lean.Grind.nestedProof`-applications.

src/Lean/Meta/Tactic/Grind/PP.lean

@@ -5,132 +5,62 @@ Authors: Leonardo de Moura
 -/
 prelude
 import Init.Grind.Util
-import Init.Grind.PP
 import Lean.Meta.Tactic.Grind.Types
-import Lean.Meta.Tactic.Grind.Arith.Model
 
 namespace Lean.Meta.Grind
 
 /-- Helper function for pretty printing the state for debugging purposes. -/
-def Goal.ppENodeRef (goal : Goal) (e : Expr) : MetaM MessageData := do
-  let some n := goal.getENode? e | return "_"
-  let type ← inferType e
-  let u ← getLevel type
-  let d := mkApp3 (mkConst ``Grind.node_def [u]) (toExpr n.idx) type e
-  return m!"{d}"
-
-@[inherit_doc Goal.ppENodeRef]
-def ppENodeRef (e : Expr) : GoalM MessageData := do
-  (← get).ppENodeRef e
+def ppENodeRef (e : Expr) : GoalM Format := do
+  let some n ← getENode? e | return "_"
+  return f!"#{n.idx}"
 
 /-- Helper function for pretty printing the state for debugging purposes. -/
-private def Goal.ppENodeDeclValue (goal : Goal) (e : Expr) : MetaM MessageData := do
+def ppENodeDeclValue (e : Expr) : GoalM Format := do
   if e.isApp && !(← isLitValue e) then
     e.withApp fun f args => do
       let r ← if f.isConst then
-        pure m!"{f}"
+        ppExpr f
       else
-        goal.ppENodeRef f
+        ppENodeRef f
       let mut r := r
       for arg in args do
-        r := r ++ " " ++ (← goal.ppENodeRef arg)
+        r := r ++ " " ++ (← ppENodeRef arg)
       return r
   else
     ppExpr e
 
 /-- Helper function for pretty printing the state for debugging purposes. -/
-private def Goal.ppENodeDecl (goal : Goal) (e : Expr) : MetaM MessageData := do
-  let mut r := m!"{← goal.ppENodeRef e} := {← goal.ppENodeDeclValue e}"
-  let n ← goal.getENode e
+def ppENodeDecl (e : Expr) : GoalM Format := do
+  let mut r := f!"{← ppENodeRef e} := {← ppENodeDeclValue e}"
+  let n ← getENode e
   unless isSameExpr e n.root do
-    r := r ++ m!" ↦ {← goal.ppENodeRef n.root}"
+    r := r ++ f!" ↦ {← ppENodeRef n.root}"
   if n.interpreted then
     r := r ++ ", [val]"
   if n.ctor then
     r := r ++ ", [ctor]"
   if grind.debug.get (← getOptions) then
-    if let some target := goal.getTarget? e then
-      r := r ++ m!" ↝ {← goal.ppENodeRef target}"
+    if let some target ← getTarget? e then
+      r := r ++ f!" ↝ {← ppENodeRef target}"
   return r
 
 /-- Pretty print goal state for debugging purposes. -/
-def Goal.ppState (goal : Goal) : MetaM MessageData := do
-  let mut r := m!"Goal:"
-  let nodes := goal.getENodes
+def ppState : GoalM Format := do
+  let mut r := f!"Goal:"
+  let nodes ← getENodes
   for node in nodes do
-    r := r ++ "\n" ++ (← goal.ppENodeDecl node.self)
-  let eqcs := goal.getEqcs
+    r := r ++ "\n" ++ (← ppENodeDecl node.self)
+  let eqcs ← getEqcs
   for eqc in eqcs do
     if eqc.length > 1 then
-      r := r ++ "\n" ++ "{" ++ (MessageData.joinSep (← eqc.mapM goal.ppENodeRef) ", ") ++  "}"
+      r := r ++ "\n" ++ "{" ++ (Format.joinSep (← eqc.mapM ppENodeRef) ", ") ++  "}"
   return r
 
-def ppGoals (goals : List Goal) : MetaM MessageData := do
-  let mut r := m!""
+def ppGoals (goals : List Goal) : GrindM Format := do
+  let mut r := f!""
   for goal in goals do
-    let m ← goal.ppState
-    r := r ++ Format.line ++ m
+    let (f, _) ← GoalM.run goal ppState
+    r := r ++ Format.line ++ f
   return r
 
-private def ppExprArray (cls : Name) (header : String) (es : Array Expr) (clsElem : Name := Name.mkSimple "_") : MessageData :=
-  let es := es.map fun e => .trace { cls := clsElem} m!"{e}" #[]
-  .trace { cls } header es
-
-private def ppEqcs (goal : Goal) : MetaM (Array MessageData) := do
-   let mut trueEqc?  : Option MessageData := none
-   let mut falseEqc? : Option MessageData := none
-   let mut otherEqcs : Array MessageData := #[]
-   for eqc in goal.getEqcs do
-     if Option.isSome <| eqc.find? (·.isTrue) then
-       let eqc := eqc.filter fun e => !e.isTrue
-       unless eqc.isEmpty do
-         trueEqc? := ppExprArray `eqc "True propositions" eqc.toArray `prop
-     else if Option.isSome <| eqc.find? (·.isFalse) then
-       let eqc := eqc.filter fun e => !e.isFalse
-       unless eqc.isEmpty do
-         falseEqc? := ppExprArray `eqc "False propositions" eqc.toArray `prop
-     else if let e :: _ :: _ := eqc then
-       -- We may want to add a flag to pretty print equivalence classes of nested proofs
-       unless (← isProof e) do
-         otherEqcs := otherEqcs.push <| .trace { cls := `eqc } (.group ("{" ++ (MessageData.joinSep (eqc.map toMessageData) ("," ++ Format.line)) ++  "}")) #[]
-   let mut result := #[]
-   if let some trueEqc := trueEqc? then result := result.push trueEqc
-   if let some falseEqc := falseEqc? then result := result.push falseEqc
-   unless otherEqcs.isEmpty do
-     result := result.push <| .trace { cls := `eqc } "Equivalence classes" otherEqcs
-   return result
-
-private def ppEMatchTheorem (thm : EMatchTheorem) : MetaM MessageData := do
-  let m := m!"{← thm.origin.pp}\n{← inferType thm.proof}\npatterns: {thm.patterns.map ppPattern}"
-  return .trace { cls := `thm } m #[]
-
-private def ppActiveTheorems (goal : Goal) : MetaM MessageData := do
-  let m ← goal.thms.toArray.mapM ppEMatchTheorem
-  let m := m ++ (← goal.newThms.toArray.mapM ppEMatchTheorem)
-  if m.isEmpty then
-    return ""
-  else
-    return .trace { cls := `ematch } "E-matching" m
-
-def ppOffset (goal : Goal) : MetaM MessageData := do
-  let s := goal.arith.offset
-  let nodes := s.nodes
-  if nodes.isEmpty then return ""
-  let model ← Arith.Offset.mkModel goal
-  let mut ms := #[]
-  for (e, val) in model do
-    ms := ms.push <| .trace { cls := `assign } m!"{e} := {val}" #[]
-  return .trace { cls := `offset } "Assignment satisfying offset contraints" ms
-
-def goalToMessageData (goal : Goal) : MetaM MessageData := goal.mvarId.withContext do
-  let mut m : Array MessageData := #[.ofGoal goal.mvarId]
-  m := m.push <| ppExprArray `facts "Asserted facts" goal.facts.toArray `prop
-  m := m ++ (← ppEqcs goal)
-  m := m.push (← ppActiveTheorems goal)
-  m := m.push (← ppOffset goal)
-  addMessageContextFull <| MessageData.joinSep m.toList ""
-
-def goalsToMessageData (goals : List Goal) : MetaM MessageData :=
-  return MessageData.joinSep (← goals.mapM goalToMessageData) m!"\n"
-
 end Lean.Meta.Grind

src/Lean/Meta/Tactic/Grind/Proj.lean

@@ -30,7 +30,7 @@ def propagateProjEq (parent : Expr) : GoalM Unit := do
     let parentNew ← shareCommon (mkApp parent.appFn! ctor)
     internalize parentNew (← getGeneration parent)
     pure parentNew
-  trace_goal[grind.debug.proj] "{parentNew}"
+  trace[grind.debug.proj] "{parentNew}"
   let idx := info.numParams + info.i
   unless idx < ctor.getAppNumArgs do return ()
   let v := ctor.getArg! idx

src/Lean/Meta/Tactic/Grind/Propagate.lean

@@ -7,8 +7,6 @@ prelude
 import Init.Grind
 import Lean.Meta.Tactic.Grind.Proof
 import Lean.Meta.Tactic.Grind.PropagatorAttr
-import Lean.Meta.Tactic.Grind.Simp
-import Lean.Meta.Tactic.Grind.Internalize
 
 namespace Lean.Meta.Grind
 
@@ -99,8 +97,6 @@ builtin_grind_propagator propagateNotUp ↑Not := fun e => do
   else if (← isEqTrue a) then
     -- a = True → (Not a) = False
     pushEqFalse e <| mkApp2 (mkConst ``Lean.Grind.not_eq_of_eq_true) a (← mkEqTrueProof a)
-  else if (← isEqv e a) then
-    closeGoal <| mkApp2 (mkConst ``Lean.Grind.false_of_not_eq_self) a (← mkEqProof e a)
 
 /--
 Propagates truth values downwards for a negation expression `Not a` based on the truth value of `Not a`.
@@ -126,59 +122,24 @@ builtin_grind_propagator propagateEqUp ↑Eq := fun e => do
   else if (← isEqTrue b) then
     pushEq e a <| mkApp3 (mkConst ``Lean.Grind.eq_eq_of_eq_true_right) a b (← mkEqTrueProof b)
   else if (← isEqv a b) then
-    pushEqTrue e <| mkEqTrueCore e (← mkEqProof a b)
+    pushEqTrue e <| mkApp2 (mkConst ``eq_true) e (← mkEqProof a b)
 
 /-- Propagates `Eq` downwards -/
 builtin_grind_propagator propagateEqDown ↓Eq := fun e => do
   if (← isEqTrue e) then
     let_expr Eq _ a b := e | return ()
-    pushEq a b <| mkOfEqTrueCore e (← mkEqTrueProof e)
-
-/-- Propagates `EqMatch` downwards -/
-builtin_grind_propagator propagateEqMatchDown ↓Grind.EqMatch := fun e => do
-  if (← isEqTrue e) then
-    let_expr Grind.EqMatch _ a b origin := e | return ()
-    markCaseSplitAsResolved origin
-    pushEq a b <| mkOfEqTrueCore e (← mkEqTrueProof e)
+    pushEq a b <| mkApp2 (mkConst ``of_eq_true) e (← mkEqTrueProof e)
 
 /-- Propagates `HEq` downwards -/
 builtin_grind_propagator propagateHEqDown ↓HEq := fun e => do
   if (← isEqTrue e) then
     let_expr HEq _ a _ b := e | return ()
-    pushHEq a b <| mkOfEqTrueCore e (← mkEqTrueProof e)
+    pushHEq a b <| mkApp2 (mkConst ``of_eq_true) e (← mkEqTrueProof e)
 
 /-- Propagates `HEq` upwards -/
 builtin_grind_propagator propagateHEqUp ↑HEq := fun e => do
   let_expr HEq _ a _ b := e | return ()
   if (← isEqv a b) then
-    pushEqTrue e <| mkEqTrueCore e (← mkHEqProof a b)
-
-/-- Propagates `ite` upwards -/
-builtin_grind_propagator propagateIte ↑ite := fun e => do
-  let_expr f@ite α c h a b := e | return ()
-  if (← isEqTrue c) then
-    pushEq e a <| mkApp6 (mkConst ``ite_cond_eq_true f.constLevels!) α c h a b (← mkEqTrueProof c)
-  else if (← isEqFalse c) then
-    pushEq e b <| mkApp6 (mkConst ``ite_cond_eq_false f.constLevels!) α c h a b (← mkEqFalseProof c)
-
-/-- Propagates `dite` upwards -/
-builtin_grind_propagator propagateDIte ↑dite := fun e => do
-  let_expr f@dite α c h a b := e | return ()
-  if (← isEqTrue c) then
-     let h₁ ← mkEqTrueProof c
-     let ah₁ := mkApp a (mkOfEqTrueCore c h₁)
-     let p ← simp ah₁
-     let r := p.expr
-     let h₂ ← p.getProof
-     internalize r (← getGeneration e)
-     pushEq e r <| mkApp8 (mkConst ``Grind.dite_cond_eq_true' f.constLevels!) α c h a b r h₁ h₂
-  else if (← isEqFalse c) then
-     let h₁ ← mkEqFalseProof c
-     let bh₁ := mkApp b (mkApp2 (mkConst ``of_eq_false) c h₁)
-     let p ← simp bh₁
-     let r := p.expr
-     let h₂ ← p.getProof
-     internalize r (← getGeneration e)
-     pushEq e r <| mkApp8 (mkConst ``Grind.dite_cond_eq_false' f.constLevels!) α c h a b r h₁ h₂
+    pushEqTrue e <| mkApp2 (mkConst ``eq_true) e (← mkHEqProof a b)
 
 end Lean.Meta.Grind

src/Lean/Meta/Tactic/Grind/Simp.lean

@@ -9,7 +9,6 @@ import Lean.Meta.Tactic.Assert
 import Lean.Meta.Tactic.Simp.Main
 import Lean.Meta.Tactic.Grind.Util
 import Lean.Meta.Tactic.Grind.Types
-import Lean.Meta.Tactic.Grind.DoNotSimp
 import Lean.Meta.Tactic.Grind.MarkNestedProofs
 
 namespace Lean.Meta.Grind
@@ -34,7 +33,6 @@ def simp (e : Expr) : GrindM Simp.Result := do
   let e' ← eraseIrrelevantMData e'
   let e' ← foldProjs e'
   let e' ← normalizeLevels e'
-  let e' ← eraseDoNotSimp e'
   let e' ← canon e'
   let e' ← shareCommon e'
   trace[grind.simp] "{e}\n===>\n{e'}"

src/Lean/Meta/Tactic/Grind/SimpUtil.lean

@@ -1,32 +0,0 @@
-/-
-Copyright (c) 2025 Amazon.com, Inc. or its affiliates. All Rights Reserved.
-Released under Apache 2.0 license as described in the file LICENSE.
-Authors: Leonardo de Moura
--/
-prelude
-import Lean.Meta.Tactic.Simp.Simproc
-import Lean.Meta.Tactic.Grind.Simp
-import Lean.Meta.Tactic.Grind.DoNotSimp
-
-namespace Lean.Meta.Grind
-
-/-- Returns the array of simprocs used by `grind`. -/
-protected def getSimprocs : MetaM (Array Simprocs) := do
-  let s ← grindNormSimprocExt.getSimprocs
-  let s ← addDoNotSimp s
-  return #[s, (← Simp.getSEvalSimprocs)]
-
-/-- Returns the simplification context used by `grind`. -/
-protected def getSimpContext : MetaM Simp.Context := do
-  let thms ← grindNormExt.getTheorems
-  Simp.mkContext
-    (config := { arith := true })
-    (simpTheorems := #[thms])
-    (congrTheorems := (← getSimpCongrTheorems))
-
-@[export lean_grind_normalize]
-def normalizeImp (e : Expr) : MetaM Expr := do
-  let (r, _) ← Meta.simp e (← Grind.getSimpContext) (← Grind.getSimprocs)
-  return r.expr
-
-end Lean.Meta.Grind

src/Lean/Meta/Tactic/Grind/Split.lean

@@ -1,178 +0,0 @@
-/-
-Copyright (c) 2025 Amazon.com, Inc. or its affiliates. All Rights Reserved.
-Released under Apache 2.0 license as described in the file LICENSE.
-Authors: Leonardo de Moura
--/
-prelude
-import Lean.Meta.Tactic.Grind.Types
-import Lean.Meta.Tactic.Grind.Intro
-import Lean.Meta.Tactic.Grind.Cases
-import Lean.Meta.Tactic.Grind.CasesMatch
-
-namespace Lean.Meta.Grind
-
-inductive CaseSplitStatus where
-  | resolved
-  | notReady
-  | ready (numCases : Nat) (isRec := false)
-  deriving Inhabited, BEq
-
-/-- Given `c`, the condition of an `if-then-else`, check whether we need to case-split on the `if-then-else` or not -/
-private def checkIteCondStatus (c : Expr) : GoalM CaseSplitStatus := do
-  if (← isEqTrue c <||> isEqFalse c) then
-    return .resolved
-  else
-    return .ready 2
-
-/--
-Given `e` of the form `a ∨ b`, check whether we are ready to case-split on `e`.
-That is, `e` is `True`, but neither `a` nor `b` is `True`."
--/
-private def checkDisjunctStatus (e a b : Expr) : GoalM CaseSplitStatus := do
-  if (← isEqTrue e) then
-    if (← isEqTrue a <||> isEqTrue b) then
-      return .resolved
-    else
-      return .ready 2
-  else if (← isEqFalse e) then
-    return .resolved
-  else
-    return .notReady
-
-/--
-Given `e` of the form `a ∧ b`, check whether we are ready to case-split on `e`.
-That is, `e` is `False`, but neither `a` nor `b` is `False`.
- -/
-private def checkConjunctStatus (e a b : Expr) : GoalM CaseSplitStatus := do
-  if (← isEqTrue e) then
-    return .resolved
-  else if (← isEqFalse e) then
-    if (← isEqFalse a <||> isEqFalse b) then
-      return .resolved
-    else
-      return .ready 2
-  else
-    return .notReady
-
-/--
-Given `e` of the form `@Eq Prop a b`, check whether we are ready to case-split on `e`.
-There are two cases:
-1- `e` is `True`, but neither both `a` and `b` are `True`, nor both `a` and `b` are `False`.
-2- `e` is `False`, but neither `a` is `True` and `b` is `False`, nor `a` is `False` and `b` is `True`.
--/
-private def checkIffStatus (e a b : Expr) : GoalM CaseSplitStatus := do
-  if (← isEqTrue e) then
-    if (← (isEqTrue a <&&> isEqTrue b) <||> (isEqFalse a <&&> isEqFalse b)) then
-      return .resolved
-    else
-      return .ready 2
-  else if (← isEqFalse e) then
-    if (← (isEqTrue a <&&> isEqFalse b) <||> (isEqFalse a <&&> isEqTrue b)) then
-      return .resolved
-    else
-      return .ready 2
-  else
-    return .notReady
-
-private def checkCaseSplitStatus (e : Expr) : GoalM CaseSplitStatus := do
-  match_expr e with
-  | Or a b => checkDisjunctStatus e a b
-  | And a b => checkConjunctStatus e a b
-  | Eq _ a b => checkIffStatus e a b
-  | ite _ c _ _ _ => checkIteCondStatus c
-  | dite _ c _ _ _ => checkIteCondStatus c
-  | _ =>
-    if (← isResolvedCaseSplit e) then
-      trace[grind.debug.split] "split resolved: {e}"
-      return .resolved
-    if let some info := isMatcherAppCore? (← getEnv) e then
-      return .ready info.numAlts
-    let .const declName .. := e.getAppFn | unreachable!
-    if let some info ← isInductivePredicate? declName then
-      if (← isEqTrue e) then
-        return .ready info.ctors.length info.isRec
-    return .notReady
-
-private inductive SplitCandidate where
-  | none
-  | some (c : Expr) (numCases : Nat) (isRec : Bool)
-
-/-- Returns the next case-split to be performed. It uses a very simple heuristic. -/
-private def selectNextSplit? : GoalM SplitCandidate := do
-  if (← isInconsistent) then return .none
-  if (← checkMaxCaseSplit) then return .none
-  go (← get).splitCandidates .none []
-where
-  go (cs : List Expr) (c? : SplitCandidate) (cs' : List Expr) : GoalM SplitCandidate := do
-    match cs with
-    | [] =>
-      modify fun s => { s with splitCandidates := cs'.reverse }
-      if let .some _ numCases isRec := c? then
-        let numSplits := (← get).numSplits
-        -- We only increase the number of splits if there is more than one case or it is recursive.
-        let numSplits := if numCases > 1 || isRec then numSplits + 1 else numSplits
-        -- Remark: we reset `numEmatch` after each case split.
-        -- We should consider other strategies in the future.
-        modify fun s => { s with numSplits, numEmatch := 0 }
-      return c?
-    | c::cs =>
-    match (← checkCaseSplitStatus c) with
-    | .notReady => go cs c? (c::cs')
-    | .resolved => go cs c? cs'
-    | .ready numCases isRec =>
-    match c? with
-    | .none => go cs (.some c numCases isRec) cs'
-    | .some c' numCases' _ =>
-     let isBetter : GoalM Bool := do
-       if numCases == 1 && !isRec && numCases' > 1 then
-         return true
-       if (← getGeneration c) < (← getGeneration c') then
-         return true
-       return numCases < numCases'
-     if (← isBetter) then
-        go cs (.some c numCases isRec) (c'::cs')
-      else
-        go cs c? (c::cs')
-
-/-- Constructs a major premise for the `cases` tactic used by `grind`. -/
-private def mkCasesMajor (c : Expr) : GoalM Expr := do
-  match_expr c with
-  | And a b => return mkApp3 (mkConst ``Grind.or_of_and_eq_false) a b (← mkEqFalseProof c)
-  | ite _ c _ _ _ => return mkEM c
-  | dite _ c _ _ _ => return mkEM c
-  | Eq _ a b =>
-    if (← isEqTrue c) then
-      return mkApp3 (mkConst ``Grind.of_eq_eq_true) a b (← mkEqTrueProof c)
-    else
-      return mkApp3 (mkConst ``Grind.of_eq_eq_false) a b (← mkEqFalseProof c)
-  | _ => return mkOfEqTrueCore c (← mkEqTrueProof c)
-
-/-- Introduces new hypotheses in each goal. -/
-private def introNewHyp (goals : List Goal) (acc : List Goal) (generation : Nat) : GrindM (List Goal) := do
-  match goals with
-  | [] => return acc.reverse
-  | goal::goals => introNewHyp goals ((← intros generation goal) ++ acc) generation
-
-/--
-Selects a case-split from the list of candidates,
-and returns a new list of goals if successful.
--/
-def splitNext : GrindTactic := fun goal => do
-  let (goals?, _) ← GoalM.run goal do
-    let .some c numCases isRec ← selectNextSplit?
-      | return none
-    let gen ← getGeneration c
-    let genNew := if numCases > 1 || isRec then gen+1 else gen
-    trace_goal[grind.split] "{c}, generation: {gen}"
-    let mvarIds ← if (← isMatcherApp c) then
-      casesMatch (← get).mvarId c
-    else
-      let major ← mkCasesMajor c
-      cases (← get).mvarId major
-    let goal ← get
-    let goals := mvarIds.map fun mvarId => { goal with mvarId }
-    let goals ← introNewHyp goals [] genNew
-    return some goals
-  return goals?
-
-end Lean.Meta.Grind

src/Lean/Meta/Tactic/Grind/Types.lean

@@ -13,20 +13,23 @@ import Lean.Meta.CongrTheorems
 import Lean.Meta.AbstractNestedProofs
 import Lean.Meta.Tactic.Simp.Types
 import Lean.Meta.Tactic.Util
-import Lean.Meta.Tactic.Grind.ENodeKey
 import Lean.Meta.Tactic.Grind.Canon
 import Lean.Meta.Tactic.Grind.Attr
-import Lean.Meta.Tactic.Grind.Arith.Types
 import Lean.Meta.Tactic.Grind.EMatchTheorem
 
 namespace Lean.Meta.Grind
 
+@[inline] def isSameExpr (a b : Expr) : Bool :=
+  -- It is safe to use pointer equality because we hashcons all expressions
+  -- inserted into the E-graph
+  unsafe ptrEq a b
+
 /-- We use this auxiliary constant to mark delayed congruence proofs. -/
 def congrPlaceholderProof := mkConst (Name.mkSimple "[congruence]")
 
 /--
 Returns `true` if `e` is `True`, `False`, or a literal value.
-See `Lean.Meta.LitValues` for supported literals.
+See `LitValues` for supported literals.
 -/
 def isInterpreted (e : Expr) : MetaM Bool := do
   if e.isTrue || e.isFalse then return true
@@ -56,16 +59,16 @@ structure CongrTheoremCacheKey where
   f       : Expr
   numArgs : Nat
 
--- We manually define `BEq` because we want to use pointer equality.
+-- We manually define `BEq` because we wannt to use pointer equality.
 instance : BEq CongrTheoremCacheKey where
   beq a b := isSameExpr a.f b.f && a.numArgs == b.numArgs
 
--- We manually define `Hashable` because we want to use pointer equality.
+-- We manually define `Hashable` because we wannt to use pointer equality.
 instance : Hashable CongrTheoremCacheKey where
   hash a := mixHash (unsafe ptrAddrUnsafe a.f).toUInt64 (hash a.numArgs)
 
 /-- State for the `GrindM` monad. -/
-structure State where
+structure CoreState where
   canon      : Canon.State := {}
   /-- `ShareCommon` (aka `Hashconsing`) state. -/
   scState    : ShareCommon.State.{0} ShareCommon.objectFactory := ShareCommon.State.mk _
@@ -80,17 +83,12 @@ structure State where
   simpStats  : Simp.Stats := {}
   trueExpr   : Expr
   falseExpr  : Expr
-  /--
-  Used to generate trace messages of the for `[grind] working on <tag>`,
-  and implement the macro `trace_goal`.
-  -/
-  lastTag    : Name := .anonymous
 
 private opaque MethodsRefPointed : NonemptyType.{0}
 private def MethodsRef : Type := MethodsRefPointed.type
 instance : Nonempty MethodsRef := MethodsRefPointed.property
 
-abbrev GrindM := ReaderT MethodsRef $ ReaderT Context $ StateRefT State MetaM
+abbrev GrindM := ReaderT MethodsRef $ ReaderT Context $ StateRefT CoreState MetaM
 
 /-- Returns the user-defined configuration options -/
 def getConfig : GrindM Grind.Config :=
@@ -125,12 +123,12 @@ def abstractNestedProofs (e : Expr) : GrindM Expr := do
 
 /--
 Applies hash-consing to `e`. Recall that all expressions in a `grind` goal have
-been hash-consed. We perform this step before we internalize expressions.
+been hash-consing. We perform this step before we internalize expressions.
 -/
 def shareCommon (e : Expr) : GrindM Expr := do
-  modifyGet fun { canon, scState, nextThmIdx, congrThms, trueExpr, falseExpr, simpStats, lastTag } =>
+  modifyGet fun { canon, scState, nextThmIdx, congrThms, trueExpr, falseExpr, simpStats } =>
     let (e, scState) := ShareCommon.State.shareCommon scState e
-    (e, { canon, scState, nextThmIdx, congrThms, trueExpr, falseExpr, simpStats, lastTag })
+    (e, { canon, scState, nextThmIdx, congrThms, trueExpr, falseExpr, simpStats })
 
 /--
 Canonicalizes nested types, type formers, and instances in `e`.
@@ -195,7 +193,7 @@ structure ENode where
   interpreted : Bool := false
   /-- `ctor := true` if the head symbol is a constructor application. -/
   ctor : Bool := false
-  /-- `hasLambdas := true` if the equivalence class contains lambda expressions. -/
+  /-- `hasLambdas := true` if equivalence class contains lambda expressions. -/
   hasLambdas : Bool := false
   /--
   If `heqProofs := true`, then some proofs in the equivalence class are based
@@ -209,6 +207,7 @@ structure ENode where
   generation : Nat := 0
   /-- Modification time -/
   mt : Nat := 0
+  -- TODO: see Lean 3 implementation
   deriving Inhabited, Repr
 
 def ENode.isCongrRoot (n : ENode) :=
@@ -221,6 +220,20 @@ structure NewEq where
   proof : Expr
   isHEq : Bool
 
+/--
+Key for the `ENodeMap` and `ParentMap` map.
+We use pointer addresses and rely on the fact all internalized expressions
+have been hash-consed, i.e., we have applied `shareCommon`.
+-/
+private structure ENodeKey where
+  expr : Expr
+
+instance : Hashable ENodeKey where
+  hash k := unsafe (ptrAddrUnsafe k.expr).toUInt64
+
+instance : BEq ENodeKey where
+  beq k₁ k₂ := isSameExpr k₁.expr k₂.expr
+
 abbrev ENodeMap := PHashMap ENodeKey ENode
 
 /--
@@ -351,8 +364,6 @@ structure Goal where
   gmt          : Nat := 0
   /-- Next unique index for creating ENodes -/
   nextIdx      : Nat := 0
-  /-- State of arithmetic procedures -/
-  arith        : Arith.State := {}
   /-- Active theorems that we have performed ematching at least once. -/
   thms         : PArray EMatchTheorem := {}
   /-- Active theorems that we have not performed any round of ematching yet. -/
@@ -364,24 +375,10 @@ structure Goal where
   thmMap       : EMatchTheorems
   /-- Number of theorem instances generated so far -/
   numInstances : Nat := 0
-  /-- Number of E-matching rounds performed in this goal since the last case-split. -/
-  numEmatch    : Nat := 0
   /-- (pre-)instances found so far. It includes instances that failed to be instantiated. -/
   preInstances : PreInstanceSet := {}
   /-- new facts to be processed. -/
   newFacts     : Std.Queue NewFact := ∅
-  /-- `match` auxiliary functions whose equations have already been created and activated. -/
-  matchEqNames : PHashSet Name := {}
-  /-- Case-split candidates. -/
-  splitCandidates : List Expr := []
-  /-- Number of splits performed to get to this goal. -/
-  numSplits : Nat := 0
-  /-- Case-splits that do not have to be performed anymore. -/
-  resolvedSplits : PHashSet ENodeKey := {}
-  /-- Next local E-match theorem idx. -/
-  nextThmIdx : Nat := 0
-  /-- Asserted facts -/
-  facts      : PArray Expr := {}
   deriving Inhabited
 
 def Goal.admit (goal : Goal) : MetaM Unit :=
@@ -395,25 +392,6 @@ abbrev GoalM := StateRefT Goal GrindM
 @[inline] def GoalM.run' (goal : Goal) (x : GoalM Unit) : GrindM Goal :=
   goal.mvarId.withContext do StateRefT'.run' (x *> get) goal
 
-def updateLastTag : GoalM Unit := do
-  if (← isTracingEnabledFor `grind) then
-    let currTag ← (← get).mvarId.getTag
-    if currTag != (← getThe Grind.State).lastTag then
-      trace[grind] "working on goal `{currTag}`"
-      modifyThe Grind.State fun s => { s with lastTag := currTag }
-
-/--
-Macro similar to `trace[...]`, but it includes the trace message `trace[grind] "working on <current goal>"`
-if the tag has changed since the last trace message.
--/
-macro "trace_goal[" id:ident "]" s:(interpolatedStr(term) <|> term) : doElem => do
-  let msg ← if s.raw.getKind == interpolatedStrKind then `(m! $(⟨s⟩)) else `(($(⟨s⟩) : MessageData))
-  `(doElem| do
-    let cls := $(quote id.getId.eraseMacroScopes)
-    if (← Lean.isTracingEnabledFor cls) then
-      updateLastTag
-      Lean.addTrace cls $msg)
-
 /--
 A helper function used to mark a theorem instance found by the E-matching module.
 It returns `true` if it is a new instance and `false` otherwise.
@@ -438,37 +416,18 @@ def addTheoremInstance (proof : Expr) (prop : Expr) (generation : Nat) : GoalM U
 def checkMaxInstancesExceeded : GoalM Bool := do
   return (← get).numInstances >= (← getConfig).instances
 
-/-- Returns `true` if the maximum number of case-splits has been reached. -/
-def checkMaxCaseSplit : GoalM Bool := do
-  return (← get).numSplits >= (← getConfig).splits
-
-/-- Returns `true` if the maximum number of E-matching rounds has been reached. -/
-def checkMaxEmatchExceeded : GoalM Bool := do
-  return (← get).numEmatch >= (← getConfig).ematch
-
 /--
 Returns `some n` if `e` has already been "internalized" into the
 Otherwise, returns `none`s.
 -/
-def Goal.getENode? (goal : Goal) (e : Expr) : Option ENode :=
-  goal.enodes.find? { expr := e }
-
-@[inline, inherit_doc Goal.getENode?]
 def getENode? (e : Expr) : GoalM (Option ENode) :=
-  return (← get).getENode? e
-
-def throwNonInternalizedExpr (e : Expr) : CoreM α :=
-  throwError "internal `grind` error, term has not been internalized{indentExpr e}"
+  return (← get).enodes.find? { expr := e }
 
 /-- Returns node associated with `e`. It assumes `e` has already been internalized. -/
-def Goal.getENode (goal : Goal) (e : Expr) : CoreM ENode := do
-  let some n := goal.enodes.find? { expr := e }
-    | throwNonInternalizedExpr e
-  return n
-
-@[inline, inherit_doc Goal.getENode]
 def getENode (e : Expr) : GoalM ENode := do
-  (← get).getENode e
+  let some n := (← get).enodes.find? { expr := e }
+    | throwError "internal `grind` error, term has not been internalized{indentExpr e}"
+  return n
 
 /-- Returns the generation of the given term. Is assumes it has been internalized -/
 def getGeneration (e : Expr) : GoalM Nat :=
@@ -499,53 +458,30 @@ def isRoot (e : Expr) : GoalM Bool := do
   return isSameExpr n.root e
 
 /-- Returns the root element in the equivalence class of `e` IF `e` has been internalized. -/
-def Goal.getRoot? (goal : Goal) (e : Expr) : Option Expr := Id.run do
-  let some n ← goal.getENode? e | return none
+def getRoot? (e : Expr) : GoalM (Option Expr) := do
+  let some n ← getENode? e | return none
   return some n.root
 
-@[inline, inherit_doc Goal.getRoot?]
-def getRoot? (e : Expr) : GoalM (Option Expr) := do
-  return (← get).getRoot? e
-
 /-- Returns the root element in the equivalence class of `e`. -/
-def Goal.getRoot (goal : Goal) (e : Expr) : CoreM Expr :=
-  return (← goal.getENode e).root
-
-@[inline, inherit_doc Goal.getRoot]
-def getRoot (e : Expr) : GoalM Expr := do
-  (← get).getRoot e
+def getRoot (e : Expr) : GoalM Expr :=
+  return (← getENode e).root
 
 /-- Returns the root enode in the equivalence class of `e`. -/
 def getRootENode (e : Expr) : GoalM ENode := do
   getENode (← getRoot e)
 
-/--
-Returns the next element in the equivalence class of `e`
-if `e` has been internalized in the given goal.
--/
-def Goal.getNext? (goal : Goal) (e : Expr) : Option Expr := Id.run do
-  let some n ← goal.getENode? e | return none
-  return some n.next
-
 /-- Returns the next element in the equivalence class of `e`. -/
-def Goal.getNext (goal : Goal) (e : Expr) : CoreM Expr :=
-  return (← goal.getENode e).next
-
-@[inline, inherit_doc Goal.getRoot]
-def getNext (e : Expr) : GoalM Expr := do
-  (← get).getNext e
+def getNext (e : Expr) : GoalM Expr :=
+  return (← getENode e).next
 
 /-- Returns `true` if `e` has already been internalized. -/
 def alreadyInternalized (e : Expr) : GoalM Bool :=
   return (← get).enodes.contains { expr := e }
 
-def Goal.getTarget? (goal : Goal) (e : Expr) : Option Expr := Id.run do
-  let some n ← goal.getENode? e | return none
+def getTarget? (e : Expr) : GoalM (Option Expr) := do
+  let some n ← getENode? e | return none
   return n.target?
 
-@[inline] def getTarget? (e : Expr) : GoalM (Option Expr) := do
-  return (← get).getTarget? e
-
 /--
 If `isHEq` is `false`, it pushes `lhs = rhs` with `proof` to `newEqs`.
 Otherwise, it pushes `HEq lhs rhs`.
@@ -699,9 +635,7 @@ def mkEqFalseProof (a : Expr) : GoalM Expr := do
 
 /-- Marks current goal as inconsistent without assigning `mvarId`. -/
 def markAsInconsistent : GoalM Unit := do
-  unless (← get).inconsistent do
-    trace[grind] "closed `{← (← get).mvarId.getTag}`"
-    modify fun s => { s with inconsistent := true }
+  modify fun s => { s with inconsistent := true }
 
 /--
 Closes the current goal using the given proof of `False` and
@@ -717,23 +651,11 @@ def closeGoal (falseProof : Expr) : GoalM Unit := do
     else
       mvarId.assign (← mkFalseElim target falseProof)
 
-def Goal.getENodes (goal : Goal) : Array ENode :=
-  -- We must sort because we are using pointer addresses as keys in `enodes`
-  let nodes := goal.enodes.toArray.map (·.2)
-  nodes.qsort fun a b => a.idx < b.idx
-
 /-- Returns all enodes in the goal -/
 def getENodes : GoalM (Array ENode) := do
-  return (← get).getENodes
-
-/-- Executes `f` to each term in the equivalence class containing `e` -/
-@[inline] def traverseEqc (e : Expr) (f : ENode → GoalM Unit) : GoalM Unit := do
-  let mut curr := e
-  repeat
-    let n ← getENode curr
-    f n
-    if isSameExpr n.next e then return ()
-    curr := n.next
+  -- We must sort because we are using pointer addresses as keys in `enodes`
+  let nodes := (← get).enodes.toArray.map (·.2)
+  return nodes.qsort fun a b => a.idx < b.idx
 
 def forEachENode (f : ENode → GoalM Unit) : GoalM Unit := do
   let nodes ← getENodes
@@ -747,7 +669,7 @@ def filterENodes (p : ENode → GoalM Bool) : GoalM (Array ENode) := do
       ref.modify (·.push n)
   ref.get
 
-def forEachEqcRoot (f : ENode → GoalM Unit) : GoalM Unit := do
+def forEachEqc (f : ENode → GoalM Unit) : GoalM Unit := do
   let nodes ← getENodes
   for n in nodes do
     if isSameExpr n.self n.root then
@@ -782,45 +704,24 @@ def applyFallback : GoalM Unit := do
   fallback
 
 /-- Returns expressions in the given expression equivalence class. -/
-partial def Goal.getEqc (goal : Goal) (e : Expr) : List Expr :=
+partial def getEqc (e : Expr) : GoalM (List Expr) :=
   go e e []
 where
-  go (first : Expr) (e : Expr) (acc : List Expr) : List Expr := Id.run do
-    let some next ← goal.getNext? e | acc
+  go (first : Expr) (e : Expr) (acc : List Expr) : GoalM (List Expr) := do
+    let next ← getNext e
     let acc := e :: acc
     if isSameExpr first next then
       return acc
     else
       go first next acc
 
-@[inline, inherit_doc Goal.getEqc]
-partial def getEqc (e : Expr) : GoalM (List Expr) :=
-  return (← get).getEqc e
-
 /-- Returns all equivalence classes in the current goal. -/
-partial def Goal.getEqcs (goal : Goal) : List (List Expr) := Id.run do
-  let mut r : List (List Expr) := []
-  let nodes ← goal.getENodes
+partial def getEqcs : GoalM (List (List Expr)) := do
+  let mut r := []
+  let nodes ← getENodes
   for node in nodes do
     if isSameExpr node.root node.self then
-      r := goal.getEqc node.self :: r
+      r := (← getEqc node.self) :: r
   return r
 
-@[inline, inherit_doc Goal.getEqcs]
-def getEqcs : GoalM (List (List Expr)) :=
-  return (← get).getEqcs
-
-/-- Returns `true` if `e` is a case-split that does not need to be performed anymore. -/
-def isResolvedCaseSplit (e : Expr) : GoalM Bool :=
-  return (← get).resolvedSplits.contains { expr := e }
-
-/--
-Mark `e` as a case-split that does not need to be performed anymore.
-Remark: we currently use this feature to disable `match`-case-splits
--/
-def markCaseSplitAsResolved (e : Expr) : GoalM Unit := do
-  unless (← isResolvedCaseSplit e) do
-    trace_goal[grind.split.resolved] "{e}"
-    modify fun s => { s with resolvedSplits := s.resolvedSplits.insert { expr := e } }
-
 end Lean.Meta.Grind

src/Lean/Meta/Tactic/Grind/Util.lean

@@ -100,14 +100,12 @@ def _root_.Lean.MVarId.clearAuxDecls (mvarId : MVarId) : MetaM MVarId := mvarId.
 /--
 In the `grind` tactic, during `Expr` internalization, we don't expect to find `Expr.mdata`.
 This function ensures `Expr.mdata` is not found during internalization.
-Recall that we do not internalize `Expr.lam` children.
-Recall that we still have to process `Expr.forallE` because of `ForallProp.lean`.
-Moreover, we may not want to reduce `p → q` to `¬p ∨ q` when `(p q : Prop)`.
+Recall that we do not internalize `Expr.forallE` and `Expr.lam` components.
 -/
 def eraseIrrelevantMData (e : Expr) : CoreM Expr := do
   let pre (e : Expr) := do
     match e with
-    | .letE .. | .lam .. => return .done e
+    | .letE .. | .lam .. | .forallE .. => return .done e
     | .mdata _ e => return .continue e
     | _ => return .continue e
   Core.transform e (pre := pre)
@@ -118,14 +116,11 @@ Converts nested `Expr.proj`s into projection applications if possible.
 def foldProjs (e : Expr) : MetaM Expr := do
   let post (e : Expr) := do
     let .proj structName idx s := e | return .done e
-    let some info := getStructureInfo? (← getEnv) structName |
-      trace[grind.issues] "found `Expr.proj` but `{structName}` is not marked as structure{indentExpr e}"
-      return .done e
+    let some info := getStructureInfo? (← getEnv) structName | return .done e
     if h : idx < info.fieldNames.size then
       let fieldName := info.fieldNames[idx]
       return .done (← mkProjection s fieldName)
     else
-      trace[grind.issues] "found `Expr.proj` with invalid field index `{idx}`{indentExpr e}"
       return .done e
   Meta.transform e (post := post)
 
@@ -140,11 +135,4 @@ def normalizeLevels (e : Expr) : CoreM Expr := do
     | _ => return .continue
   Core.transform e (pre := pre)
 
-/--
-Normalizes the given expression using the `grind` simplification theorems and simprocs.
-This function is used for normalzing E-matching patterns. Note that it does not return a proof.
--/
-@[extern "lean_grind_normalize"] -- forward definition
-opaque normalize (e : Expr) : MetaM Expr
-
 end Lean.Meta.Grind

src/Lean/Meta/Tactic/LinearArith/Nat/Simp.lean

@@ -50,24 +50,18 @@ def simpCnstr? (e : Expr) : MetaM (Option (Expr × Expr)) := do
   if let some arg := e.not? then
     let mut eNew?   := none
     let mut thmName := Name.anonymous
-    match_expr arg with
-    | LE.le α _ _ _ =>
-      if α.isConstOf ``Nat then
-        eNew?   := some (← mkLE (← mkAdd (arg.getArg! 3) (mkNatLit 1)) (arg.getArg! 2))
-        thmName := ``Nat.not_le_eq
-    | GE.ge α _ _ _ =>
-      if α.isConstOf ``Nat then
-        eNew?   := some (← mkLE (← mkAdd (arg.getArg! 2) (mkNatLit 1)) (arg.getArg! 3))
-        thmName := ``Nat.not_ge_eq
-    | LT.lt α _ _ _ =>
-      if α.isConstOf ``Nat then
-        eNew?   := some (← mkLE (arg.getArg! 3) (arg.getArg! 2))
-        thmName := ``Nat.not_lt_eq
-    | GT.gt α _ _ _ =>
-      if α.isConstOf ``Nat then
-        eNew?   := some (← mkLE (arg.getArg! 2) (arg.getArg! 3))
-        thmName := ``Nat.not_gt_eq
-    | _ => pure ()
+    if arg.isAppOfArity ``LE.le 4 then
+      eNew?   := some (← mkLE (← mkAdd (arg.getArg! 3) (mkNatLit 1)) (arg.getArg! 2))
+      thmName := ``Nat.not_le_eq
+    else if arg.isAppOfArity ``GE.ge 4 then
+      eNew?   := some (← mkLE (← mkAdd (arg.getArg! 2) (mkNatLit 1)) (arg.getArg! 3))
+      thmName := ``Nat.not_ge_eq
+    else if arg.isAppOfArity ``LT.lt 4 then
+      eNew?   := some (← mkLE (arg.getArg! 3) (arg.getArg! 2))
+      thmName := ``Nat.not_lt_eq
+    else if arg.isAppOfArity ``GT.gt 4 then
+      eNew?   := some (← mkLE (arg.getArg! 2) (arg.getArg! 3))
+      thmName := ``Nat.not_gt_eq
     if let some eNew := eNew? then
       let h₁ := mkApp2 (mkConst thmName) (arg.getArg! 2) (arg.getArg! 3)
       if let some (eNew', h₂) ← simpCnstrPos? eNew then

src/Lean/Parser/Basic.lean

@@ -1583,8 +1583,8 @@ namespace TokenMap
 
 def insert (map : TokenMap α) (k : Name) (v : α) : TokenMap α :=
   match map.find? k with
-  | none    => RBMap.insert map k [v]
-  | some vs => RBMap.insert map k (v::vs)
+  | none    => .insert map k [v]
+  | some vs => .insert map k (v::vs)
 
 instance : Inhabited (TokenMap α) where
   default := RBMap.empty

src/Lean/ParserCompiler.lean

@@ -103,8 +103,11 @@ partial def compileParserExpr (e : Expr) : MetaM Expr := do
           name := c', levelParams := []
           type := ty, value := value, hints := ReducibilityHints.opaque, safety := DefinitionSafety.safe
         }
-        addAndCompile decl
-        modifyEnv (ctx.combinatorAttr.setDeclFor · c c')
+        let env ← getEnv
+        let env ← match env.addAndCompile {} decl with
+          | Except.ok    env => pure env
+          | Except.error kex => do throwError (← (kex.toMessageData {}).toString)
+        setEnv <| ctx.combinatorAttr.setDeclFor env c c'
         if cinfo.type.isConst then
           if let some kind ← parserNodeKind? cinfo.value! then
             -- If the parser is parameter-less and produces a node of kind `kind`,

src/Lean/PrettyPrinter/Delaborator/Builtins.lean

@@ -4,6 +4,7 @@ Released under Apache 2.0 license as described in the file LICENSE.
 Authors: Sebastian Ullrich, Leonardo de Moura, Gabriel Ebner, Mario Carneiro
 -/
 prelude
+import Lean.Parser
 import Lean.PrettyPrinter.Delaborator.Attributes
 import Lean.PrettyPrinter.Delaborator.Basic
 import Lean.PrettyPrinter.Delaborator.SubExpr

src/Lean/Server/Completion.lean

@@ -5,7 +5,6 @@ Authors: Leonardo de Moura, Marc Huisinga
 -/
 prelude
 import Lean.Server.Completion.CompletionCollectors
-import Std.Data.HashMap
 
 namespace Lean.Server.Completion
 open Lsp

src/Lean/Server/Requests.lean

@@ -97,7 +97,7 @@ abbrev RequestT m := ReaderT RequestContext <| ExceptT RequestError m
 /-- Workers execute request handlers in this monad. -/
 abbrev RequestM := ReaderT RequestContext <| EIO RequestError
 
-abbrev RequestTask.pure (a : α) : RequestTask α := Task.pure (.ok a)
+abbrev RequestTask.pure (a : α) : RequestTask α := .pure (.ok a)
 
 instance : MonadLift IO RequestM where
   monadLift x := do