refactor: generalize some simp methods

We are going to reuse these methods to implement a symbolic/partial evaluator.

.github/ISSUE_TEMPLATE/bug_report.md

@@ -9,15 +9,9 @@ assignees: ''
 
 ### Prerequisites
 
-Please put an X between the brackets as you perform the following steps:
-
-* [ ] Check that your issue is not already filed:
-      https://github.com/leanprover/lean4/issues
-* [ ] Reduce the issue to a minimal, self-contained, reproducible test case.
-      Avoid dependencies to Mathlib or Batteries.
-* [ ] Test your test case against the latest nightly release, for example on
-      https://live.lean-lang.org/#project=lean-nightly
-      (You can also use the settings there to switch to “Lean nightly”)
+* [ ] Put an X between the brackets on this line if you have done all of the following:
+    * Check that your issue is not already [filed](https://github.com/leanprover/lean4/issues).
+    * Reduce the issue to a minimal, self-contained, reproducible test case. Avoid dependencies to mathlib4 or std4.
 
 ### Description
 
@@ -39,8 +33,8 @@ Please put an X between the brackets as you perform the following steps:
 
 ### Versions
 
-[Output of `#eval Lean.versionString`]
-[OS version, if not using live.lean-lang.org.]
+[Output of `#eval Lean.versionString` or of `lean --version` in the folder that the issue occured in]
+[OS version]
 
 ### Additional Information
 

.github/PULL_REQUEST_TEMPLATE.md

@@ -1,14 +1,13 @@
-# Read this section before submitting
+# Read and remove this section before submitting
 
 * Ensure your PR follows the [External Contribution Guidelines](https://github.com/leanprover/lean4/blob/master/CONTRIBUTING.md).
 * Please make sure the PR has excellent documentation and tests. If we label it `missing documentation` or `missing tests` then it needs fixing!
-* Include the link to your `RFC` or `bug` issue in the description.
+* Add the link to your `RFC` or `bug` issue below.
 * If the issue does not already have approval from a developer, submit the PR as draft.
-* The PR title/description will become the commit message. Keep it up-to-date as the PR evolves.
-* If you rebase your PR onto `nightly-with-mathlib` then CI will test Mathlib against your PR.
-* You can manage the `awaiting-review`, `awaiting-author`, and `WIP` labels yourself, by writing a comment containing one of these labels on its own line.
-* Remove this section, up to and including the `---` before submitting.
+* Remove this section before submitting.
 
----
+You can manage the `awaiting-review`, `awaiting-author`, and `WIP` labels yourself, by writing a comment containing one of these labels on its own line.
 
-Closes #0000 (`RFC` or `bug` issue number fixed by this PR, if any)
+# Summary
+
+Link to `RFC` or `bug` issue:

.github/workflows/actionlint.yml

@@ -1,22 +0,0 @@
-name: Actionlint
-on:
-  push:
-    branches:
-      - 'master'
-    paths:
-      - '.github/**'
-  pull_request:
-    paths:
-      - '.github/**'
-  merge_group:
-
-jobs:
-  actionlint:
-    runs-on: ubuntu-latest
-    steps:
-    - name: Checkout
-      uses: actions/checkout@v3
-    - name: actionlint
-      uses: raven-actions/actionlint@v1
-      with:
-        pyflakes: false # we do not use python scripts

.github/workflows/check-prelude.yml

@@ -1,26 +0,0 @@
-name: Check for modules that should use `prelude`
-
-on: [pull_request]
-
-jobs:
-  check-prelude:
-    runs-on: ubuntu-latest
-    steps:
-      - name: Checkout
-        uses: actions/checkout@v4
-        with:
-          # the default is to use a virtual merge commit between the PR and master: just use the PR
-          ref: ${{ github.event.pull_request.head.sha }}
-          sparse-checkout: src/Lean
-      - name: Check Prelude
-        run: |
-          failed_files=""
-          while IFS= read -r -d '' file; do
-            if ! grep -q "^prelude$" "$file"; then
-              failed_files="$failed_files$file\n"
-            fi
-          done < <(find src/Lean -name '*.lean' -print0)
-          if [ -n "$failed_files" ]; then
-            echo -e "The following files should use 'prelude':\n$failed_files"
-            exit 1
-          fi

.github/workflows/check-stage0.yml

@@ -1,57 +0,0 @@
-name: Check for stage0 changes
-
-on:
-  merge_group:
-  pull_request:
-
-jobs:
-  check-stage0-on-queue:
-    runs-on: ubuntu-latest
-    steps:
-    - uses: actions/checkout@v4
-      with:
-        ref: ${{ github.event.pull_request.head.sha }}
-        filter: blob:none
-        fetch-depth: 0
-
-    - name: Find base commit
-      if: github.event_name == 'pull_request'
-      run: echo "BASE=$(git merge-base origin/${{ github.base_ref }} HEAD)" >> "$GITHUB_ENV"
-
-    - name: Identify stage0 changes
-      run: |
-        git diff "${BASE:-HEAD^}..HEAD" --name-only -- stage0 |
-          grep -v -x -F $'stage0/src/stdlib_flags.h\nstage0/src/lean.mk.in' \
-          > "$RUNNER_TEMP/stage0" || true
-        if test -s "$RUNNER_TEMP/stage0"
-        then
-          echo "CHANGES=yes" >> "$GITHUB_ENV"
-        else
-          echo "CHANGES=no" >> "$GITHUB_ENV"
-        fi
-      shell: bash
-
-    - if: github.event_name == 'pull_request'
-      name: Set label
-      uses: actions/github-script@v7
-      with:
-        script: |
-          const { owner, repo, number: issue_number  } = context.issue;
-          if (process.env.CHANGES == 'yes') {
-            await github.rest.issues.addLabels({ owner, repo, issue_number, labels: ['changes-stage0'] }).catch(() => {});
-          } else {
-            await github.rest.issues.removeLabel({ owner, repo, issue_number, name: 'changes-stage0' }).catch(() => {});
-          }
-
-    - if: env.CHANGES == 'yes'
-      name: Report changes
-      run: |
-        echo "Found changes to stage0/, please do not merge using the merge queue." | tee "$GITHUB_STEP_SUMMARY"
-        # shellcheck disable=SC2129
-        echo '```'                  >> "$GITHUB_STEP_SUMMARY"
-        cat  "$RUNNER_TEMP/stage0"  >> "$GITHUB_STEP_SUMMARY"
-        echo '```'                  >> "$GITHUB_STEP_SUMMARY"
-
-    - if: github.event_name == 'merge_group' && env.CHANGES == 'yes'
-      name: Fail when on the merge queue
-      run: exit 1

.github/workflows/ci.yml

@@ -6,6 +6,7 @@ on:
     tags:
       - '*'
   pull_request:
+    types: [opened, synchronize, reopened, labeled]
   merge_group:
   schedule:
     - cron: '0 7 * * *'  # 8AM CET/11PM PT
@@ -20,10 +21,8 @@ jobs:
   configure:
     runs-on: ubuntu-latest
     outputs:
-      # 0: PRs without special label
-      # 1: PRs with `merge-ci` label, merge queue checks, master commits
-      # 2: PRs with `release-ci` label, releases (incl. nightlies)
-      check-level: ${{ steps.set-level.outputs.check-level }}
+      # Should we run only a quick CI? Yes on a pull request without the full-ci label
+      quick: ${{ steps.set-quick.outputs.quick }}
       # The build matrix, dynamically generated here
       matrix: ${{ steps.set-matrix.outputs.result }}
       # Should we make a nightly release? If so, this output contains the lean version string, else it is empty
@@ -40,6 +39,155 @@ jobs:
       RELEASE_TAG: ${{ steps.set-release.outputs.RELEASE_TAG }}
 
     steps:
+      - name: Run quick CI?
+        id: set-quick
+        env:
+          quick: ${{
+            github.event_name == 'pull_request' && !contains( github.event.pull_request.labels.*.name, 'full-ci')
+           }}
+        run: |
+          echo "quick=${{env.quick}}" >> $GITHUB_OUTPUT
+
+      - name: Configure build matrix
+        id: set-matrix
+        uses: actions/github-script@v7
+        with:
+          script: |
+            const quick = ${{ steps.set-quick.outputs.quick }};
+            console.log(`quick: ${quick}`)
+            let matrix = [
+              {
+                // portable release build: use channel with older glibc (2.27)
+                "name": "Linux LLVM",
+                "os": "ubuntu-latest",
+                "release": false,
+                "quick": false,
+                "shell": "nix-shell --arg pkgsDist \"import (fetchTarball \\\"channel:nixos-19.03\\\") {{}}\" --run \"bash -euxo pipefail {0}\"",
+                "llvm-url": "https://github.com/leanprover/lean-llvm/releases/download/15.0.1/lean-llvm-x86_64-linux-gnu.tar.zst",
+                "prepare-llvm": "../script/prepare-llvm-linux.sh lean-llvm*",
+                "binary-check": "ldd -v",
+                // foreign code may be linked against more recent glibc
+                // reverse-ffi needs to be updated to link to LLVM libraries
+                "CTEST_OPTIONS": "-E 'foreign|leanlaketest_reverse-ffi'",
+                "CMAKE_OPTIONS": "-DLLVM=ON -DLLVM_CONFIG=${GITHUB_WORKSPACE}/build/llvm-host/bin/llvm-config"
+              },
+              {
+                "name": "Linux release",
+                "os": "ubuntu-latest",
+                "release": true,
+                "quick": true,
+                "shell": "nix-shell --arg pkgsDist \"import (fetchTarball \\\"channel:nixos-19.03\\\") {{}}\" --run \"bash -euxo pipefail {0}\"",
+                "llvm-url": "https://github.com/leanprover/lean-llvm/releases/download/15.0.1/lean-llvm-x86_64-linux-gnu.tar.zst",
+                "prepare-llvm": "../script/prepare-llvm-linux.sh lean-llvm*",
+                "binary-check": "ldd -v",
+                // foreign code may be linked against more recent glibc
+                "CTEST_OPTIONS": "-E 'foreign'"
+              },
+              {
+                "name": "Linux",
+                "os": "ubuntu-latest",
+                "check-stage3": true,
+                "test-speedcenter": true,
+                "quick": false,
+              },
+              {
+                "name": "Linux Debug",
+                "os": "ubuntu-latest",
+                "quick": false,
+                "CMAKE_OPTIONS": "-DCMAKE_BUILD_TYPE=Debug",
+                // exclude seriously slow tests
+                "CTEST_OPTIONS": "-E 'interactivetest|leanpkgtest|laketest|benchtest'"
+              },
+              {
+                "name": "Linux fsanitize",
+                "os": "ubuntu-latest",
+                "quick": false,
+                // turn off custom allocator & symbolic functions to make LSAN do its magic
+                "CMAKE_OPTIONS": "-DLEAN_EXTRA_CXX_FLAGS=-fsanitize=address,undefined -DLEANC_EXTRA_FLAGS='-fsanitize=address,undefined -fsanitize-link-c++-runtime' -DSMALL_ALLOCATOR=OFF -DBSYMBOLIC=OFF",
+                // exclude seriously slow/problematic tests (laketests crash)
+                "CTEST_OPTIONS": "-E 'interactivetest|leanpkgtest|laketest|benchtest'"
+              },
+              {
+                "name": "macOS",
+                "os": "macos-latest",
+                "release": true,
+                "quick": false,
+                "shell": "bash -euxo pipefail {0}",
+                "llvm-url": "https://github.com/leanprover/lean-llvm/releases/download/15.0.1/lean-llvm-x86_64-apple-darwin.tar.zst",
+                "prepare-llvm": "../script/prepare-llvm-macos.sh lean-llvm*",
+                "binary-check": "otool -L",
+                "tar": "gtar" // https://github.com/actions/runner-images/issues/2619
+              },
+              {
+                "name": "macOS aarch64",
+                "os": "macos-latest",
+                "release": true,
+                "quick": false,
+                "cross": true,
+                "shell": "bash -euxo pipefail {0}",
+                "CMAKE_OPTIONS": "-DUSE_GMP=OFF -DLEAN_INSTALL_SUFFIX=-darwin_aarch64",
+                "llvm-url": "https://github.com/leanprover/lean-llvm/releases/download/15.0.1/lean-llvm-aarch64-apple-darwin.tar.zst https://github.com/leanprover/lean-llvm/releases/download/15.0.1/lean-llvm-x86_64-apple-darwin.tar.zst",
+                "prepare-llvm": "EXTRA_FLAGS=--target=aarch64-apple-darwin ../script/prepare-llvm-macos.sh lean-llvm-aarch64-* lean-llvm-x86_64-*",
+                "binary-check": "otool -L",
+                "tar": "gtar" // https://github.com/actions/runner-images/issues/2619
+              },
+              {
+                "name": "Windows",
+                "os": "windows-2022",
+                "release": true,
+                "quick": false,
+                "shell": "msys2 {0}",
+                "CMAKE_OPTIONS": "-G \"Unix Makefiles\" -DUSE_GMP=OFF",
+                // for reasons unknown, interactivetests are flaky on Windows
+                "CTEST_OPTIONS": "--repeat until-pass:2",
+                "llvm-url": "https://github.com/leanprover/lean-llvm/releases/download/15.0.1/lean-llvm-x86_64-w64-windows-gnu.tar.zst",
+                "prepare-llvm": "../script/prepare-llvm-mingw.sh lean-llvm*",
+                "binary-check": "ldd"
+              },
+              {
+                "name": "Linux aarch64",
+                "os": "ubuntu-latest",
+                "CMAKE_OPTIONS": "-DUSE_GMP=OFF -DLEAN_INSTALL_SUFFIX=-linux_aarch64",
+                "release": true,
+                "quick": false,
+                "cross": true,
+                "shell": "nix-shell --arg pkgsDist \"import (fetchTarball \\\"channel:nixos-19.03\\\") {{ localSystem.config = \\\"aarch64-unknown-linux-gnu\\\"; }}\" --run \"bash -euxo pipefail {0}\"",
+                "llvm-url": "https://github.com/leanprover/lean-llvm/releases/download/15.0.1/lean-llvm-x86_64-linux-gnu.tar.zst https://github.com/leanprover/lean-llvm/releases/download/15.0.1/lean-llvm-aarch64-linux-gnu.tar.zst",
+                "prepare-llvm": "EXTRA_FLAGS=--target=aarch64-unknown-linux-gnu ../script/prepare-llvm-linux.sh lean-llvm-aarch64-* lean-llvm-x86_64-*"
+              },
+              {
+                "name": "Linux 32bit",
+                "os": "ubuntu-latest",
+                // Use 32bit on stage0 and stage1 to keep oleans compatible
+                "CMAKE_OPTIONS": "-DSTAGE0_USE_GMP=OFF -DSTAGE0_LEAN_EXTRA_CXX_FLAGS='-m32' -DSTAGE0_LEANC_OPTS='-m32' -DSTAGE0_MMAP=OFF -DUSE_GMP=OFF -DLEAN_EXTRA_CXX_FLAGS='-m32' -DLEANC_OPTS='-m32' -DMMAP=OFF -DLEAN_INSTALL_SUFFIX=-linux_x86",
+                "cmultilib": true,
+                "release": true,
+                "quick": false,
+                "cross": true,
+                "shell": "bash -euxo pipefail {0}"
+              },
+              {
+                "name": "Web Assembly",
+                "os": "ubuntu-latest",
+                // Build a native 32bit binary in stage0 and use it to compile the oleans and the wasm build
+                "CMAKE_OPTIONS": "-DCMAKE_C_COMPILER_WORKS=1 -DSTAGE0_USE_GMP=OFF -DSTAGE0_LEAN_EXTRA_CXX_FLAGS='-m32' -DSTAGE0_LEANC_OPTS='-m32' -DSTAGE0_CMAKE_CXX_COMPILER=clang++ -DSTAGE0_CMAKE_C_COMPILER=clang -DSTAGE0_CMAKE_EXECUTABLE_SUFFIX=\"\" -DUSE_GMP=OFF -DMMAP=OFF -DSTAGE0_MMAP=OFF -DCMAKE_AR=../emsdk/emsdk-main/upstream/emscripten/emar -DCMAKE_TOOLCHAIN_FILE=../emsdk/emsdk-main/upstream/emscripten/cmake/Modules/Platform/Emscripten.cmake -DLEAN_INSTALL_SUFFIX=-linux_wasm32",
+                "wasm": true,
+                "cmultilib": true,
+                "release": true,
+                "quick": false,
+                "cross": true,
+                "shell": "bash -euxo pipefail {0}",
+                // Just a few selected tests because wasm is slow
+                "CTEST_OPTIONS": "-R \"leantest_1007\\.lean|leantest_Format\\.lean|leanruntest\\_1037.lean|leanruntest_ac_rfl\\.lean\""
+              }
+            ];
+            console.log(`matrix:\n${JSON.stringify(matrix, null, 2)}`)
+            if (quick) {
+              return matrix.filter((job) => job.quick)
+            } else {
+              return matrix
+            }
+
       - name: Checkout
         uses: actions/checkout@v3
         # don't schedule nightlies on forks
@@ -53,8 +201,8 @@ jobs:
             git fetch nightly --tags
             LEAN_VERSION_STRING="nightly-$(date -u +%F)"
             # do nothing if commit already has a different tag
-            if [[ "$(git name-rev --name-only --tags --no-undefined HEAD 2> /dev/null || echo "$LEAN_VERSION_STRING")" == "$LEAN_VERSION_STRING" ]]; then
-              echo "nightly=$LEAN_VERSION_STRING" >> "$GITHUB_OUTPUT"
+            if [[ $(git name-rev --name-only --tags --no-undefined HEAD 2> /dev/null || echo $LEAN_VERSION_STRING) == $LEAN_VERSION_STRING ]]; then
+              echo "nightly=$LEAN_VERSION_STRING" >> $GITHUB_OUTPUT
             fi
           fi
 
@@ -62,7 +210,7 @@ jobs:
         if: startsWith(github.ref, 'refs/tags/') && github.repository == 'leanprover/lean4'
         id: set-release
         run: |
-          TAG_NAME="${GITHUB_REF##*/}"
+          TAG_NAME=${GITHUB_REF##*/}
 
           # From https://github.com/fsaintjacques/semver-tool/blob/master/src/semver
 
@@ -79,181 +227,15 @@ jobs:
 
           if [[ ${TAG_NAME} =~ ${SEMVER_REGEX} ]]; then
             echo "Tag ${TAG_NAME} matches SemVer regex, with groups ${BASH_REMATCH[1]} ${BASH_REMATCH[2]} ${BASH_REMATCH[3]} ${BASH_REMATCH[4]}"
-            {
-              echo "LEAN_VERSION_MAJOR=${BASH_REMATCH[1]}"
-              echo "LEAN_VERSION_MINOR=${BASH_REMATCH[2]}"
-              echo "LEAN_VERSION_PATCH=${BASH_REMATCH[3]}"
-              echo "LEAN_SPECIAL_VERSION_DESC=${BASH_REMATCH[4]##-}"
-              echo "RELEASE_TAG=$TAG_NAME"
-            } >> "$GITHUB_OUTPUT"
+            echo "LEAN_VERSION_MAJOR=${BASH_REMATCH[1]}" >> $GITHUB_OUTPUT
+            echo "LEAN_VERSION_MINOR=${BASH_REMATCH[2]}" >> $GITHUB_OUTPUT
+            echo "LEAN_VERSION_PATCH=${BASH_REMATCH[3]}" >> $GITHUB_OUTPUT
+            echo "LEAN_SPECIAL_VERSION_DESC=${BASH_REMATCH[4]##-}" >> $GITHUB_OUTPUT
+            echo "RELEASE_TAG=$TAG_NAME" >> $GITHUB_OUTPUT
           else
             echo "Tag ${TAG_NAME} did not match SemVer regex."
           fi
 
-      - name: Set check level
-        id: set-level
-        # We do not use github.event.pull_request.labels.*.name here because
-        # re-running a run does not update that list, and we do want to be able to
-        # rerun the workflow run after setting the `release-ci`/`merge-ci` labels.
-        run: |
-          check_level=0
-
-          if [[ -n "${{ steps.set-nightly.outputs.nightly }}" || -n "${{ steps.set-release.outputs.RELEASE_TAG }}" ]]; then
-            check_level=2
-          elif [[ "${{ github.event_name }}" != "pull_request" ]]; then
-            check_level=1
-          else
-            labels="$(gh api repos/${{ github.repository_owner }}/${{ github.event.repository.name }}/pulls/${{ github.event.pull_request.number }}) --jq '.labels'"
-            if echo "$labels" | grep -q "release-ci"; then
-              check_level=2
-            elif echo "$labels" | grep -q "merge-ci"; then
-              check_level=1
-            fi
-          fi
-
-          echo "check-level=$check_level" >> "$GITHUB_OUTPUT"
-        env:
-          GH_TOKEN: ${{ github.token }}
-
-      - name: Configure build matrix
-        id: set-matrix
-        uses: actions/github-script@v7
-        with:
-          script: |
-            const level = ${{ steps.set-level.outputs.check-level }};
-            console.log(`level: ${level}`);
-            // use large runners where available (original repo)
-            let large = ${{ github.repository == 'leanprover/lean4' }};
-            let matrix = [
-              {
-                // portable release build: use channel with older glibc (2.27)
-                "name": "Linux LLVM",
-                "os": "ubuntu-latest",
-                "release": false,
-                "check-level": 2,
-                "shell": "nix develop .#oldGlibc -c bash -euxo pipefail {0}",
-                "llvm-url": "https://github.com/leanprover/lean-llvm/releases/download/15.0.1/lean-llvm-x86_64-linux-gnu.tar.zst",
-                "prepare-llvm": "../script/prepare-llvm-linux.sh lean-llvm*",
-                "binary-check": "ldd -v",
-                // foreign code may be linked against more recent glibc
-                // reverse-ffi needs to be updated to link to LLVM libraries
-                "CTEST_OPTIONS": "-E 'foreign|leanlaketest_reverse-ffi'",
-                "CMAKE_OPTIONS": "-DLLVM=ON -DLLVM_CONFIG=${GITHUB_WORKSPACE}/build/llvm-host/bin/llvm-config"
-              },
-              {
-                "name": "Linux release",
-                "os": large ? "nscloud-ubuntu-22.04-amd64-4x8" : "ubuntu-latest",
-                "release": true,
-                "check-level": 0,
-                "shell": "nix develop .#oldGlibc -c bash -euxo pipefail {0}",
-                "llvm-url": "https://github.com/leanprover/lean-llvm/releases/download/15.0.1/lean-llvm-x86_64-linux-gnu.tar.zst",
-                "prepare-llvm": "../script/prepare-llvm-linux.sh lean-llvm*",
-                "binary-check": "ldd -v",
-                // foreign code may be linked against more recent glibc
-                "CTEST_OPTIONS": "-E 'foreign'"
-              },
-              {
-                "name": "Linux",
-                "os": large ? "nscloud-ubuntu-22.04-amd64-4x8" : "ubuntu-latest",
-                "check-stage3": level >= 2,
-                "test-speedcenter": level >= 2,
-                "check-level": 1,
-              },
-              {
-                "name": "Linux Debug",
-                "os": "ubuntu-latest",
-                "check-level": 2,
-                "CMAKE_PRESET": "debug",
-                // exclude seriously slow tests
-                "CTEST_OPTIONS": "-E 'interactivetest|leanpkgtest|laketest|benchtest'"
-              },
-              // TODO: suddenly started failing in CI
-              /*{
-                "name": "Linux fsanitize",
-                "os": "ubuntu-latest",
-                "check-level": 2,
-                // turn off custom allocator & symbolic functions to make LSAN do its magic
-                "CMAKE_PRESET": "sanitize",
-                // exclude seriously slow/problematic tests (laketests crash)
-                "CTEST_OPTIONS": "-E 'interactivetest|leanpkgtest|laketest|benchtest'"
-              },*/
-              {
-                "name": "macOS",
-                "os": "macos-13",
-                "release": true,
-                "check-level": 2,
-                "shell": "bash -euxo pipefail {0}",
-                "llvm-url": "https://github.com/leanprover/lean-llvm/releases/download/15.0.1/lean-llvm-x86_64-apple-darwin.tar.zst",
-                "prepare-llvm": "../script/prepare-llvm-macos.sh lean-llvm*",
-                "binary-check": "otool -L",
-                "tar": "gtar" // https://github.com/actions/runner-images/issues/2619
-              },
-              {
-                "name": "macOS aarch64",
-                "os": "macos-14",
-                "CMAKE_OPTIONS": "-DLEAN_INSTALL_SUFFIX=-darwin_aarch64",
-                "release": true,
-                "check-level": 1,
-                "shell": "bash -euxo pipefail {0}",
-                "llvm-url": "https://github.com/leanprover/lean-llvm/releases/download/15.0.1/lean-llvm-aarch64-apple-darwin.tar.zst",
-                "prepare-llvm": "../script/prepare-llvm-macos.sh lean-llvm*",
-                "binary-check": "otool -L",
-                "tar": "gtar" // https://github.com/actions/runner-images/issues/2619
-              },
-              {
-                "name": "Windows",
-                "os": "windows-2022",
-                "release": true,
-                "check-level": 2,
-                "shell": "msys2 {0}",
-                "CMAKE_OPTIONS": "-G \"Unix Makefiles\" -DUSE_GMP=OFF",
-                // for reasons unknown, interactivetests are flaky on Windows
-                "CTEST_OPTIONS": "--repeat until-pass:2",
-                "llvm-url": "https://github.com/leanprover/lean-llvm/releases/download/15.0.1/lean-llvm-x86_64-w64-windows-gnu.tar.zst",
-                "prepare-llvm": "../script/prepare-llvm-mingw.sh lean-llvm*",
-                "binary-check": "ldd"
-              },
-              {
-                "name": "Linux aarch64",
-                "os": "ubuntu-latest",
-                "CMAKE_OPTIONS": "-DUSE_GMP=OFF -DLEAN_INSTALL_SUFFIX=-linux_aarch64",
-                "release": true,
-                "check-level": 2,
-                "cross": true,
-                "cross_target": "aarch64-unknown-linux-gnu",
-                "shell": "nix develop .#oldGlibcAArch -c bash -euxo pipefail {0}",
-                "llvm-url": "https://github.com/leanprover/lean-llvm/releases/download/15.0.1/lean-llvm-x86_64-linux-gnu.tar.zst https://github.com/leanprover/lean-llvm/releases/download/15.0.1/lean-llvm-aarch64-linux-gnu.tar.zst",
-                "prepare-llvm": "../script/prepare-llvm-linux.sh lean-llvm-aarch64-* lean-llvm-x86_64-*"
-              },
-              {
-                "name": "Linux 32bit",
-                "os": "ubuntu-latest",
-                // Use 32bit on stage0 and stage1 to keep oleans compatible
-                "CMAKE_OPTIONS": "-DSTAGE0_USE_GMP=OFF -DSTAGE0_LEAN_EXTRA_CXX_FLAGS='-m32' -DSTAGE0_LEANC_OPTS='-m32' -DSTAGE0_MMAP=OFF -DUSE_GMP=OFF -DLEAN_EXTRA_CXX_FLAGS='-m32' -DLEANC_OPTS='-m32' -DMMAP=OFF -DLEAN_INSTALL_SUFFIX=-linux_x86",
-                "cmultilib": true,
-                "release": true,
-                "check-level": 2,
-                "cross": true,
-                "shell": "bash -euxo pipefail {0}"
-              },
-              {
-                "name": "Web Assembly",
-                "os": "ubuntu-latest",
-                // Build a native 32bit binary in stage0 and use it to compile the oleans and the wasm build
-                "CMAKE_OPTIONS": "-DCMAKE_C_COMPILER_WORKS=1 -DSTAGE0_USE_GMP=OFF -DSTAGE0_LEAN_EXTRA_CXX_FLAGS='-m32' -DSTAGE0_LEANC_OPTS='-m32' -DSTAGE0_CMAKE_CXX_COMPILER=clang++ -DSTAGE0_CMAKE_C_COMPILER=clang -DSTAGE0_CMAKE_EXECUTABLE_SUFFIX=\"\" -DUSE_GMP=OFF -DMMAP=OFF -DSTAGE0_MMAP=OFF -DCMAKE_AR=../emsdk/emsdk-main/upstream/emscripten/emar -DCMAKE_TOOLCHAIN_FILE=../emsdk/emsdk-main/upstream/emscripten/cmake/Modules/Platform/Emscripten.cmake -DLEAN_INSTALL_SUFFIX=-linux_wasm32",
-                "wasm": true,
-                "cmultilib": true,
-                "release": true,
-                "check-level": 2,
-                "cross": true,
-                "shell": "bash -euxo pipefail {0}",
-                // Just a few selected tests because wasm is slow
-                "CTEST_OPTIONS": "-R \"leantest_1007\\.lean|leantest_Format\\.lean|leanruntest\\_1037.lean|leanruntest_ac_rfl\\.lean\""
-              }
-            ];
-            console.log(`matrix:\n${JSON.stringify(matrix, null, 2)}`)
-            return matrix.filter((job) => level >= job["check-level"])
-
   build:
     needs: [configure]
     if: github.event_name != 'schedule' || github.repository == 'leanprover/lean4'
@@ -265,7 +247,7 @@ jobs:
     runs-on: ${{ matrix.os }}
     defaults:
       run:
-        shell: ${{ matrix.shell || 'nix develop -c bash -euxo pipefail {0}' }}
+        shell: ${{ matrix.shell || 'nix-shell --run "bash -euxo pipefail {0}"' }}
     name: ${{ matrix.name }}
     env:
       # must be inside workspace
@@ -280,34 +262,28 @@ jobs:
       CXX: c++
       MACOSX_DEPLOYMENT_TARGET: 10.15
     steps:
+      - name: Checkout
+        uses: actions/checkout@v3
+        with:
+          submodules: true
+          # the default is to use a virtual merge commit between the PR and master: just use the PR
+          ref: ${{ github.event.pull_request.head.sha }}
       - name: Install Nix
-        uses: DeterminateSystems/nix-installer-action@main
-        if: runner.os == 'Linux' && !matrix.cmultilib
+        uses: cachix/install-nix-action@v18
+        with:
+          install_url: https://releases.nixos.org/nix/nix-2.12.0/install
+        if: matrix.os == 'ubuntu-latest' && !matrix.cmultilib
       - name: Install MSYS2
         uses: msys2/setup-msys2@v2
         with:
           msystem: clang64
           # `:p` means prefix with appropriate msystem prefix
           pacboy: "make python cmake:p clang:p ccache:p gmp:p git zip unzip diffutils binutils tree zstd:p tar"
-        if: runner.os == 'Windows'
+        if: matrix.os == 'windows-2022'
       - name: Install Brew Packages
         run: |
           brew install ccache tree zstd coreutils gmp
-        if: runner.os == 'macOS'
-      - name: Checkout
-        uses: actions/checkout@v4
-        with:
-          # the default is to use a virtual merge commit between the PR and master: just use the PR
-          ref: ${{ github.event.pull_request.head.sha }}
-      # Do check out some CI-relevant files from virtual merge commit to accommodate CI changes on
-      # master (as the workflow files themselves are always taken from the merge)
-      # (needs to be after "Install *" to use the right shell)
-      - name: CI Merge Checkout
-        run: |
-          git fetch --depth=1 origin ${{ github.sha }}
-          git checkout FETCH_HEAD flake.nix flake.lock
-        if: github.event_name == 'pull_request'
-      # (needs to be after "Checkout" so files don't get overriden)
+        if: matrix.os == 'macos-latest'
       - name: Setup emsdk
         uses: mymindstorm/setup-emsdk@v12
         with:
@@ -323,31 +299,29 @@ jobs:
         uses: actions/cache@v3
         with:
           path: .ccache
-          key: ${{ matrix.name }}-build-v3-${{ github.event.pull_request.head.sha }}
+          key: ${{ matrix.name }}-build-v3-${{ github.sha }}
           # fall back to (latest) previous cache
           restore-keys: |
             ${{ matrix.name }}-build-v3
-      # open nix-shell once for initial setup
       - name: Setup
         run: |
-          ccache --zero-stats
-        if: runner.os == 'Linux'
-      - name: Set up NPROC
+          # open nix-shell once for initial setup
+          true
+        if: matrix.os == 'ubuntu-latest'
+      - name: Set up core dumps
         run: |
-          echo "NPROC=$(nproc 2>/dev/null || sysctl -n hw.logicalcpu 2>/dev/null || echo 4)" >> $GITHUB_ENV
+          mkdir -p $PWD/coredumps
+          # store in current directory, for easy uploading together with binary
+          echo $PWD/coredumps/%e.%p.%t | sudo tee /proc/sys/kernel/core_pattern
+        if: matrix.os == 'ubuntu-latest'
       - name: Build
         run: |
           mkdir build
           cd build
-          # arguments passed to `cmake`
+          ulimit -c unlimited # coredumps
           # this also enables githash embedding into stage 1 library
           OPTIONS=(-DCHECK_OLEAN_VERSION=ON)
           OPTIONS+=(-DLEAN_EXTRA_MAKE_OPTS=-DwarningAsError=true)
-          if [[ -n '${{ matrix.cross_target }}' ]]; then
-            # used by `prepare-llvm`
-            export EXTRA_FLAGS=--target=${{ matrix.cross_target }}
-            OPTIONS+=(-DLEAN_PLATFORM_TARGET=${{ matrix.cross_target }})
-          fi
           if [[ -n '${{ matrix.prepare-llvm }}' ]]; then
             wget -q ${{ matrix.llvm-url }}
             PREPARE="$(${{ matrix.prepare-llvm }})"
@@ -364,11 +338,9 @@ jobs:
             OPTIONS+=(-DLEAN_SPECIAL_VERSION_DESC=${{ needs.configure.outputs.LEAN_SPECIAL_VERSION_DESC }})
           fi
           # contortion to support empty OPTIONS with old macOS bash
-          cmake .. --preset ${{ matrix.CMAKE_PRESET || 'release' }} -B . ${{ matrix.CMAKE_OPTIONS }} ${OPTIONS[@]+"${OPTIONS[@]}"} -DLEAN_INSTALL_PREFIX=$PWD/..
-          time make -j$NPROC
-      - name: Install
-        run: |
-          make -C build install
+          cmake .. ${{ matrix.CMAKE_OPTIONS }} ${OPTIONS[@]+"${OPTIONS[@]}"} -DLEAN_INSTALL_PREFIX=$PWD/..
+          make -j4
+          make install
       - name: Check Binaries
         run: ${{ matrix.binary-check }} lean-*/bin/* || true
       - name: List Install Tree
@@ -396,43 +368,62 @@ jobs:
           build/stage1/bin/lean --stats src/Lean.lean
         if: ${{ !matrix.cross }}
       - name: Test
-        id: test
         run: |
-          time ctest --preset ${{ matrix.CMAKE_PRESET || 'release' }} --test-dir build/stage1 -j$NPROC --output-junit test-results.xml ${{ matrix.CTEST_OPTIONS }}
-        if: (matrix.wasm || !matrix.cross) && needs.configure.outputs.check-level >= 1
-      - name: Test Summary
-        uses: test-summary/action@v2
-        with:
-          paths: build/stage1/test-results.xml
-        # prefix `if` above with `always` so it's run even if tests failed
-        if: always() && steps.test.conclusion != 'skipped'
+          cd build/stage1
+          ulimit -c unlimited # coredumps
+          # exclude nonreproducible test
+          ctest -j4 --output-on-failure ${{ matrix.CTEST_OPTIONS }} < /dev/null
+        if: (matrix.wasm || !matrix.cross) && needs.configure.outputs.quick == 'false'
       - name: Check Test Binary
         run: ${{ matrix.binary-check }} tests/compiler/534.lean.out
-        if: (!matrix.cross) && steps.test.conclusion != 'skipped'
+        if: ${{ !matrix.cross && needs.configure.outputs.quick == 'false' }}
       - name: Build Stage 2
         run: |
-          make -C build -j$NPROC stage2
+          cd build
+          ulimit -c unlimited # coredumps
+          make -j4 stage2
         if: matrix.test-speedcenter
       - name: Check Stage 3
         run: |
-          make -C build -j$NPROC stage3
+          cd build
+          ulimit -c unlimited # coredumps
+          make -j4 check-stage3
         if: matrix.test-speedcenter
       - name: Test Speedcenter Benchmarks
         run: |
-          # Necessary for some timing metrics but does not work on Namespace runners
-          # and we just want to test that the benchmarks run at all here
-          #echo -1 | sudo tee /proc/sys/kernel/perf_event_paranoid
+          echo -1 | sudo tee /proc/sys/kernel/perf_event_paranoid
           export BUILD=$PWD/build PATH=$PWD/build/stage1/bin:$PATH
           cd tests/bench
           nix shell .#temci -c temci exec --config speedcenter.yaml --included_blocks fast --runs 1
         if: matrix.test-speedcenter
       - name: Check rebootstrap
         run: |
-          # clean rebuild in case of Makefile changes
-          make -C build update-stage0 && rm -rf build/stage* && make -C build -j$NPROC
-        if: matrix.name == 'Linux' && needs.configure.outputs.check-level >= 1
+          cd build
+          ulimit -c unlimited # coredumps
+          make update-stage0 && make -j4
+        if: matrix.name == 'Linux' && needs.configure.outputs.quick == 'false'
       - name: CCache stats
         run: ccache -s
+      - name: Show stacktrace for coredumps
+        if: ${{ failure() }} && matrix.os == 'ubuntu-latest'
+        run: |
+          for c in coredumps/*; do
+            progbin="$(file $c | sed "s/.*execfn: '\([^']*\)'.*/\1/")"
+            echo bt | $GDB/bin/gdb -q $progbin $c || true
+          done
+      - name: Upload coredumps
+        uses: actions/upload-artifact@v3
+        if: ${{ failure() }} && matrix.os == 'ubuntu-latest'
+        with:
+          name: coredumps-${{ matrix.name }}
+          path: |
+            ./coredumps
+            ./build/stage0/bin/lean
+            ./build/stage0/lib/lean/libleanshared.so
+            ./build/stage1/bin/lean
+            ./build/stage1/lib/lean/libleanshared.so
+            ./build/stage2/bin/lean
+            ./build/stage2/lib/lean/libleanshared.so
 
   # This job collects results from all the matrix jobs
   # This can be made the “required” job, instead of listing each
@@ -441,10 +432,9 @@ jobs:
     name: Build matrix complete
     runs-on: ubuntu-latest
     needs: build
-    # mark as merely cancelled not failed if builds are cancelled
-    if: ${{ !cancelled() }}
+    if: ${{ always() }}
     steps:
-    - if: contains(needs.*.result, 'failure')
+    - if: contains(needs.*.result, 'failure') ||  contains(needs.*.result, 'cancelled')
       uses: actions/github-script@v7
       with:
         script: |
@@ -467,7 +457,6 @@ jobs:
         with:
           files: artifacts/*/*
           fail_on_unmatched_files: true
-          prerelease: ${{ !startsWith(github.ref, 'refs/tags/v') || contains(github.ref, '-rc') }}
         env:
           GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
 
@@ -491,16 +480,16 @@ jobs:
         run: |
           git remote add nightly https://foo:'${{ secrets.PUSH_NIGHTLY_TOKEN }}'@github.com/${{ github.repository_owner }}/lean4-nightly.git
           git fetch nightly --tags
-          git tag "${{ needs.configure.outputs.nightly }}"
-          git push nightly "${{ needs.configure.outputs.nightly }}"
+          git tag ${{ needs.configure.outputs.nightly }}
+          git push nightly ${{ needs.configure.outputs.nightly }}
           git push -f origin refs/tags/${{ needs.configure.outputs.nightly }}:refs/heads/nightly
-          last_tag="$(git log HEAD^ --simplify-by-decoration --pretty="format:%d" | grep -o "nightly-[-0-9]*" | head -n 1)"
+          last_tag=$(git log HEAD^ --simplify-by-decoration --pretty="format:%d" | grep -o "nightly-[-0-9]*" | head -n 1)
           echo -e "*Changes since ${last_tag}:*\n\n" > diff.md
-          git show "$last_tag":RELEASES.md > old.md
+          git show $last_tag:RELEASES.md > old.md
           #./script/diff_changelogs.py old.md doc/changes.md >> diff.md
           diff --changed-group-format='%>' --unchanged-group-format='' old.md RELEASES.md >> diff.md || true
           echo -e "\n*Full commit log*\n" >> diff.md
-          git log --oneline "$last_tag"..HEAD | sed 's/^/* /' >> diff.md
+          git log --oneline $last_tag..HEAD | sed 's/^/* /' >> diff.md
       - name: Release Nightly
         uses: softprops/action-gh-release@v1
         with:

.github/workflows/copyright-header.yml

@@ -1,20 +0,0 @@
-name: Check for copyright header
-
-on: [pull_request]
-
-jobs:
-  check-lean-files:
-    runs-on: ubuntu-latest
-    steps:
-    - uses: actions/checkout@v4
-
-    - name: Verify .lean files start with a copyright header.
-      run: |
-        FILES=$(find ./src -type d \( -path "./src/lake/examples" -o -path "./src/lake/tests" \) -prune -o -type f -name "*.lean" -exec perl -ne 'BEGIN { $/ = undef; } print "$ARGV\n" if !m{\A/-\nCopyright}; exit;' {} \;)
-        if [ -n "$FILES" ]; then
-          echo "Found .lean files which do not have a copyright header:"
-          echo "$FILES"
-          exit 1
-        else
-          echo "All copyright headers present."
-        fi

.github/workflows/nix-ci.yml

@@ -13,36 +13,18 @@ concurrency:
   cancel-in-progress: true
 
 jobs:
-  # see ci.yml
-  configure:
-    runs-on: ubuntu-latest
-    outputs:
-      matrix: ${{ steps.set-matrix.outputs.result }}
-    steps:
-      - name: Configure build matrix
-        id: set-matrix
-        uses: actions/github-script@v7
-        with:
-          script: |
-            let large = ${{ github.repository == 'leanprover/lean4' }};
-            let matrix = [
-              {
-                "name": "Nix Linux",
-                "os": large ? "nscloud-ubuntu-22.04-amd64-8x8" : "ubuntu-latest",
-              }
-            ];
-            console.log(`matrix:\n${JSON.stringify(matrix, null, 2)}`);
-            return matrix;
-
   Build:
-    needs: [configure]
     runs-on: ${{ matrix.os }}
     defaults:
       run:
         shell: nix run .#ciShell -- bash -euxo pipefail {0}
     strategy:
       matrix:
-        include: ${{fromJson(needs.configure.outputs.matrix)}}
+        include:
+          - name: Nix Linux
+            os: ubuntu-latest
+          #- name: Nix macOS
+          #  os: macos-latest
       # complete all jobs
       fail-fast: false
     name: ${{ matrix.name }}
@@ -89,60 +71,37 @@ jobs:
         run: |
           sudo chown -R root:nixbld /nix/var/cache
           sudo chmod -R 770 /nix/var/cache
+      - name: Install Cachix
+        uses: cachix/cachix-action@v12
+        with:
+          name: lean4
+          authToken: '${{ secrets.CACHIX_AUTH_TOKEN }}'
+          skipPush: true  # we push specific outputs only
       - name: Build
         run: |
           nix build $NIX_BUILD_ARGS .#cacheRoots -o push-build
       - name: Test
         run: |
-          nix build --keep-failed $NIX_BUILD_ARGS .#test -o push-test || (ln -s /tmp/nix-build-*/source/src/build/ ./push-test; false)
-      - name: Test Summary
-        uses: test-summary/action@v2
-        with:
-          paths: push-test/test-results.xml
-        if: always()
-        continue-on-error: true
+          nix build $NIX_BUILD_ARGS .#test -o push-test
       - name: Build manual
         run: |
           nix build $NIX_BUILD_ARGS --update-input lean --no-write-lock-file ./doc#{lean-mdbook,leanInk,alectryon,test,inked} -o push-doc
           nix build $NIX_BUILD_ARGS --update-input lean --no-write-lock-file ./doc
-          # https://github.com/netlify/cli/issues/1809
-          cp -r --dereference ./result ./dist
         if: matrix.name == 'Nix Linux'
-      - name: Check manual for broken links
-        id: lychee
-        uses: lycheeverse/lychee-action@v1.9.0
-        with:
-          fail: false  # report errors but do not block CI on temporary failures
-          # gmplib.org consistently times out from GH actions
-          # the GitHub token is to avoid rate limiting
-          args: --base './dist' --no-progress --github-token ${{ secrets.GITHUB_TOKEN }} --exclude 'gmplib.org' './dist/**/*.html'
+      - name: Push to Cachix
+        run: |
+          [ -z "${{ secrets.CACHIX_AUTH_TOKEN }}" ] || cachix push -j4 lean4 ./push-* || true
       - name: Rebuild Nix Store Cache
         run: |
           rm -rf nix-store-cache || true
           nix copy ./push-* --to file://$PWD/nix-store-cache?compression=none
-      - id: deploy-info
-        name: Compute Deployment Metadata
-        run: |
-          set -e
-          python3 -c 'import base64; print("alias="+base64.urlsafe_b64encode(bytes.fromhex("${{github.sha}}")).decode("utf-8").rstrip("="))' >> "$GITHUB_OUTPUT"
-          echo "message=`git log -1 --pretty=format:"%s"`" >> "$GITHUB_OUTPUT"
-      - name: Publish manual to Netlify
-        uses: nwtgck/actions-netlify@v2.0
-        id: publish-manual
+      - name: Publish manual
+        uses: peaceiris/actions-gh-pages@v3
         with:
-          publish-dir: ./dist
-          production-branch: master
-          github-token: ${{ secrets.GITHUB_TOKEN }}
-          deploy-message: |
-            ${{ github.event_name == 'pull_request' && format('pr#{0}: {1}', github.event.number, github.event.pull_request.title) || format('ref/{0}: {1}', github.ref_name, steps.deploy-info.outputs.message) }}
-          alias: ${{ steps.deploy-info.outputs.alias }}
-          enable-commit-comment: false
-          enable-pull-request-comment: false
-          github-deployment-environment: "lean-lang.org/lean4/doc"
-          fails-without-credentials: false
-        env:
-          NETLIFY_AUTH_TOKEN: ${{ secrets.NETLIFY_AUTH_TOKEN }}
-          NETLIFY_SITE_ID: "b8e805d2-7e9b-4f80-91fb-a84d72fc4a68"
+          github_token: ${{ secrets.GITHUB_TOKEN }}
+          publish_dir: ./result
+          destination_dir: ./doc
+        if: matrix.name == 'Nix Linux' && github.ref == 'refs/heads/master' && github.event_name == 'push'
       - name: Fixup CCache Cache
         run: |
           sudo chown -R $USER /nix/var/cache

.github/workflows/pr-release.yml

@@ -6,10 +6,6 @@
 # Instead we use `workflow_run`, which essentially allows us to escalate privileges
 # (but only runs the CI as described in the `master` branch, not in the PR branch).
 
-# The main specification/documentation for this workflow is at
-# https://leanprover-community.github.io/contribute/tags_and_branches.html
-# Keep that in sync!
-
 name: PR release
 
 on:
@@ -41,7 +37,7 @@ jobs:
           name: build-.*
           name_is_regexp: true
 
-      - name: Push tag
+      - name: Push branch and tag
         if: ${{ steps.workflow-info.outputs.pullRequestNumber != '' }}
         run: |
           git init --bare lean4.git
@@ -73,20 +69,6 @@ jobs:
           # The token used here must have `workflow` privileges.
           GITHUB_TOKEN: ${{ secrets.PR_RELEASES_TOKEN }}
 
-      - name: Report release status
-        if: ${{ steps.workflow-info.outputs.pullRequestNumber != '' }}
-        uses: actions/github-script@v6
-        with:
-          script: |
-            await github.rest.repos.createCommitStatus({
-              owner: context.repo.owner,
-              repo: context.repo.repo,
-              sha: "${{ steps.workflow-info.outputs.sourceHeadSha }}",
-              state: "success",
-              context: "PR toolchain",
-              description: "${{ github.repository_owner }}/lean4-pr-releases:pr-release-${{ steps.workflow-info.outputs.pullRequestNumber }}",
-            });
-
       - name: Add label
         if: ${{ steps.workflow-info.outputs.pullRequestNumber != '' }}
         uses: actions/github-script@v7
@@ -100,14 +82,11 @@ jobs:
             })
 
       # Next, determine the most recent nightly release in this PR's history.
-      - name: Find most recent nightly in feature branch
+      - name: Find most recent nightly
         id: most-recent-nightly-tag
         if: ${{ steps.workflow-info.outputs.pullRequestNumber != '' }}
         run: |
-          git -C lean4.git remote add nightly https://github.com/leanprover/lean4-nightly.git
-          git -C lean4.git fetch nightly '+refs/tags/nightly-*:refs/tags/nightly-*'
-          git -C lean4.git tag --merged "${{ steps.workflow-info.outputs.sourceHeadSha }}" --list "nightly-*" \
-            | sort -rV | head -n 1 | sed "s/^nightly-*/MOST_RECENT_NIGHTLY=/" | tee -a "$GITHUB_ENV"
+          git ls-remote https://github.com/leanprover/lean4-nightly.git 'refs/tags/nightly-*' --sort version:refname |tail -n1| sed 's,.*refs/tags/nightly-,MOST_RECENT_NIGHTLY=,' >> $GITHUB_ENV
 
       - name: 'Setup jq'
         if: ${{ steps.workflow-info.outputs.pullRequestNumber != '' }}
@@ -118,30 +97,22 @@ jobs:
         if: ${{ steps.workflow-info.outputs.pullRequestNumber != '' }}
         id: ready
         run: |
-          echo "Most recent nightly release in your branch: $MOST_RECENT_NIGHTLY"
-          NIGHTLY_SHA=$(git -C lean4.git rev-parse "nightly-$MOST_RECENT_NIGHTLY^{commit}")
-          echo "SHA of most recent nightly release: $NIGHTLY_SHA"
+          echo "Most recent nightly: $MOST_RECENT_NIGHTLY"
+          NIGHTLY_SHA=$(git ls-remote https://github.com/leanprover/lean4-nightly.git "nightly-$MOST_RECENT_NIGHTLY"|cut -f1)
+          echo "SHA of most recent nightly: $NIGHTLY_SHA"
           MERGE_BASE_SHA=$(git -C lean4.git merge-base origin/master "${{ steps.workflow-info.outputs.sourceHeadSha }}")
           echo "SHA of merge-base: $MERGE_BASE_SHA"
           if [ "$NIGHTLY_SHA" = "$MERGE_BASE_SHA" ]; then
-            echo "The merge base of this PR coincides with the nightly release"
+            echo "Most recent nightly tag agrees with the merge base."
 
-            BATTERIES_REMOTE_TAGS="$(git ls-remote https://github.com/leanprover-community/batteries.git nightly-testing-"$MOST_RECENT_NIGHTLY")"
-            MATHLIB_REMOTE_TAGS="$(git ls-remote https://github.com/leanprover-community/mathlib4.git nightly-testing-"$MOST_RECENT_NIGHTLY")"
+            REMOTE_BRANCHES=$(git ls-remote -h https://github.com/leanprover-community/mathlib4.git nightly-testing-$MOST_RECENT_NIGHTLY)
 
-            if [[ -n "$BATTERIES_REMOTE_TAGS" ]]; then
-              echo "... and Batteries has a 'nightly-testing-$MOST_RECENT_NIGHTLY' tag."
+            if [[ -n "$REMOTE_BRANCHES" ]]; then
+              echo "... and Mathlib has a 'nightly-testing-$MOST_RECENT_NIGHTLY' branch."
               MESSAGE=""
-
-              if [[ -n "$MATHLIB_REMOTE_TAGS" ]]; then
-                echo "... and Mathlib has a 'nightly-testing-$MOST_RECENT_NIGHTLY' tag."    
-              else
-                echo "... but Mathlib does not yet have a 'nightly-testing-$MOST_RECENT_NIGHTLY' tag."
-                MESSAGE="- ❗ Mathlib CI can not be attempted yet, as the \`nightly-testing-$MOST_RECENT_NIGHTLY\` tag does not exist there yet. We will retry when you push more commits. If you rebase your branch onto \`nightly-with-mathlib\`, Mathlib CI should run now."
-              fi
             else
-              echo "... but Batteries does not yet have a 'nightly-testing-$MOST_RECENT_NIGHTLY' tag."
-              MESSAGE="- ❗ Batteries CI can not be attempted yet, as the \`nightly-testing-$MOST_RECENT_NIGHTLY\` tag does not exist there yet. We will retry when you push more commits. If you rebase your branch onto \`nightly-with-mathlib\`, Batteries CI should run now."
+              echo "... but Mathlib does not yet have a 'nightly-testing-$MOST_RECENT_NIGHTLY' branch."
+              MESSAGE="- ❗ Mathlib CI can not be attempted yet, as the 'nightly-testing-$MOST_RECENT_NIGHTLY' branch does not exist there yet. We will retry when you push more commits. It may be necessary to rebase onto 'nightly' tomorrow."
             fi
 
           else
@@ -149,26 +120,20 @@ jobs:
             echo "but 'git merge-base origin/master HEAD' reported: $MERGE_BASE_SHA"
             git -C lean4.git log -10 origin/master
 
-            git -C lean4.git fetch origin nightly-with-mathlib 
-            NIGHTLY_WITH_MATHLIB_SHA="$(git -C lean4.git rev-parse "origin/nightly-with-mathlib")"
-            MESSAGE="- ❗ Batteries/Mathlib CI will not be attempted unless your PR branches off the \`nightly-with-mathlib\` branch. Try \`git rebase $MERGE_BASE_SHA --onto $NIGHTLY_WITH_MATHLIB_SHA\`."
+            MESSAGE="- ❗ Mathlib CI will not be attempted unless you rebase your PR onto the 'nightly' branch."
           fi
 
           if [[ -n "$MESSAGE" ]]; then
 
             echo "Checking existing messages"
 
-            # The code for updating comments is duplicated in mathlib's
-            # scripts/lean-pr-testing-comments.sh
-            # so keep in sync
-
             # Use GitHub API to check if a comment already exists
-            existing_comment="$(curl -L -s -H "Authorization: token ${{ secrets.MATHLIB4_BOT }}" \
+            existing_comment=$(curl -L -s -H "Authorization: token ${{ secrets.MATHLIB4_BOT }}" \
                                     -H "Accept: application/vnd.github.v3+json" \
                                     "https://api.github.com/repos/leanprover/lean4/issues/${{ steps.workflow-info.outputs.pullRequestNumber }}/comments" \
-                                    | jq 'first(.[] | select(.body | test("^- . Mathlib") or startswith("Mathlib CI status")) | select(.user.login == "leanprover-community-mathlib4-bot"))')"
-            existing_comment_id="$(echo "$existing_comment" | jq -r .id)"
-            existing_comment_body="$(echo "$existing_comment" | jq -r .body)"
+                                    | jq '.[] | select(.body | startswith("- ❗ Mathlib") or startswith("- ✅ Mathlib") or startswith("- ❌ Mathlib") or startswith("- 💥 Mathlib") or startswith("- 🟡 Mathlib"))')
+            existing_comment_id=$(echo "$existing_comment" | jq -r .id)
+            existing_comment_body=$(echo "$existing_comment" | jq -r .body)
 
             if [[ "$existing_comment_body" != *"$MESSAGE"* ]]; then
               MESSAGE="$MESSAGE ($(date "+%Y-%m-%d %H:%M:%S"))"
@@ -178,14 +143,13 @@ jobs:
               # Append new result to the existing comment or post a new comment
               # It's essential we use the MATHLIB4_BOT token here, so that Mathlib CI can subsequently edit the comment.
               if [ -z "$existing_comment_id" ]; then
-                INTRO="Mathlib CI status ([docs](https://leanprover-community.github.io/contribute/tags_and_branches.html)):"
                 # Post new comment with a bullet point
                 echo "Posting as new comment at leanprover/lean4/issues/${{ steps.workflow-info.outputs.pullRequestNumber }}/comments"
                 curl -L -s \
                   -X POST \
                   -H "Authorization: token ${{ secrets.MATHLIB4_BOT }}" \
                   -H "Accept: application/vnd.github.v3+json" \
-                  -d "$(jq --null-input --arg intro "$INTRO" --arg val "$MESSAGE" '{"body":($intro + "\n" + $val)}')" \
+                  -d "$(jq --null-input --arg val "$MESSAGE" '{"body": $val}')" \
                   "https://api.github.com/repos/leanprover/lean4/issues/${{ steps.workflow-info.outputs.pullRequestNumber }}/comments"
               else
                 # Append new result to the existing comment
@@ -200,93 +164,18 @@ jobs:
             else
               echo "The message already exists in the comment body."
             fi
-            echo "mathlib_ready=false" >> "$GITHUB_OUTPUT"
+            echo "mathlib_ready=false" >> $GITHUB_OUTPUT
           else
-            echo "mathlib_ready=true" >> "$GITHUB_OUTPUT"
+            echo "mathlib_ready=true" >> $GITHUB_OUTPUT
           fi
 
-      - name: Report mathlib base
-        if: ${{ steps.workflow-info.outputs.pullRequestNumber != '' && steps.ready.outputs.mathlib_ready == 'true' }}
-        uses: actions/github-script@v6
-        with:
-          script: |
-            const description =
-              process.env.MOST_RECENT_NIGHTLY ?
-              "nightly-" + process.env.MOST_RECENT_NIGHTLY :
-              "not branched off nightly";
-            await github.rest.repos.createCommitStatus({
-              owner: context.repo.owner,
-              repo: context.repo.repo,
-              sha: "${{ steps.workflow-info.outputs.sourceHeadSha }}",
-              state: "success",
-              context: "PR branched off:",
-              description: description,
-            });
-
-      # We next automatically create a Batteries branch using this toolchain.
-      # Batteries doesn't itself have a mechanism to report results of CI from this branch back to Lean
-      # Instead this is taken care of by Mathlib CI, which will fail if Batteries fails.
-      - name: Cleanup workspace
-        if: steps.workflow-info.outputs.pullRequestNumber != '' && steps.ready.outputs.mathlib_ready == 'true'
-        run: |
-          sudo rm -rf ./*
-
-      # Checkout the Batteries repository with all branches
-      - name: Checkout Batteries repository
-        if: steps.workflow-info.outputs.pullRequestNumber != '' && steps.ready.outputs.mathlib_ready == 'true'
-        uses: actions/checkout@v3
-        with:
-          repository: leanprover-community/batteries
-          token: ${{ secrets.MATHLIB4_BOT }}
-          ref: nightly-testing
-          fetch-depth: 0 # This ensures we check out all tags and branches.
-
-      - name: Check if tag exists
-        if: steps.workflow-info.outputs.pullRequestNumber != '' && steps.ready.outputs.mathlib_ready == 'true'
-        id: check_batteries_tag
-        run: |
-          git config user.name "leanprover-community-mathlib4-bot"
-          git config user.email "leanprover-community-mathlib4-bot@users.noreply.github.com"
-
-          if git ls-remote --heads --tags --exit-code origin "nightly-testing-${MOST_RECENT_NIGHTLY}" >/dev/null; then
-            BASE="nightly-testing-${MOST_RECENT_NIGHTLY}"
-          else
-            echo "This shouldn't be possible: couldn't find a 'nightly-testing-${MOST_RECENT_NIGHTLY}' tag at Batteries. Falling back to 'nightly-testing'."
-            BASE=nightly-testing
-          fi
-
-          echo "Using base branch: $BASE"
-
-          EXISTS="$(git ls-remote --heads origin lean-pr-testing-${{ steps.workflow-info.outputs.pullRequestNumber }} | wc -l)"
-          echo "Branch exists: $EXISTS"
-          if [ "$EXISTS" = "0" ]; then
-            echo "Branch does not exist, creating it."
-            git switch -c lean-pr-testing-${{ steps.workflow-info.outputs.pullRequestNumber }} "$BASE"
-            echo "leanprover/lean4-pr-releases:pr-release-${{ steps.workflow-info.outputs.pullRequestNumber }}" > lean-toolchain
-            git add lean-toolchain
-            git commit -m "Update lean-toolchain for testing https://github.com/leanprover/lean4/pull/${{ steps.workflow-info.outputs.pullRequestNumber }}"
-          else
-            echo "Branch already exists, pushing an empty commit."
-            git switch lean-pr-testing-${{ steps.workflow-info.outputs.pullRequestNumber }}
-            # The Batteries `nightly-testing` or `nightly-testing-YYYY-MM-DD` branch may have moved since this branch was created, so merge their changes.
-            # (This should no longer be possible once `nightly-testing-YYYY-MM-DD` is a tag, but it is still safe to merge.)
-            git merge "$BASE" --strategy-option ours --no-commit --allow-unrelated-histories
-            git commit --allow-empty -m "Trigger CI for https://github.com/leanprover/lean4/pull/${{ steps.workflow-info.outputs.pullRequestNumber }}"
-          fi
-
-      - name: Push changes
-        if: steps.workflow-info.outputs.pullRequestNumber != '' && steps.ready.outputs.mathlib_ready == 'true'
-        run: |
-          git push origin lean-pr-testing-${{ steps.workflow-info.outputs.pullRequestNumber }}
-
-
       # We next automatically create a Mathlib branch using this toolchain.
       # Mathlib CI will be responsible for reporting back success or failure
       # to the PR comments asynchronously.
       - name: Cleanup workspace
         if: steps.workflow-info.outputs.pullRequestNumber != '' && steps.ready.outputs.mathlib_ready == 'true'
         run: |
-          sudo rm -rf ./*
+          sudo rm -rf *
 
       # Checkout the mathlib4 repository with all branches
       - name: Checkout mathlib4 repository
@@ -298,46 +187,37 @@ jobs:
           ref: nightly-testing
           fetch-depth: 0 # This ensures we check out all tags and branches.
 
-      - name: install elan
-        run: |
-          set -o pipefail
-          curl -sSfL https://github.com/leanprover/elan/releases/download/v3.0.0/elan-x86_64-unknown-linux-gnu.tar.gz | tar xz
-          ./elan-init -y --default-toolchain none
-          echo "$HOME/.elan/bin" >> "${GITHUB_PATH}"
-
-      - name: Check if tag exists
+      - name: Check if branch exists
         if: steps.workflow-info.outputs.pullRequestNumber != '' && steps.ready.outputs.mathlib_ready == 'true'
-        id: check_mathlib_tag
+        id: check_branch
         run: |
           git config user.name "leanprover-community-mathlib4-bot"
           git config user.email "leanprover-community-mathlib4-bot@users.noreply.github.com"
 
-          if git ls-remote --heads --tags --exit-code origin "nightly-testing-${MOST_RECENT_NIGHTLY}" >/dev/null; then
-            BASE="nightly-testing-${MOST_RECENT_NIGHTLY}"
+          if git branch -r | grep -q "nightly-testing-${MOST_RECENT_NIGHTLY}"; then
+            BASE=nightly-testing-${MOST_RECENT_NIGHTLY}
           else
             echo "This shouldn't be possible: couldn't find a 'nightly-testing-${MOST_RECENT_NIGHTLY}' branch at Mathlib. Falling back to 'nightly-testing'."
             BASE=nightly-testing
           fi
 
-          echo "Using base tag: $BASE"
+          echo "Using base branch: $BASE"
 
-          EXISTS="$(git ls-remote --heads origin lean-pr-testing-${{ steps.workflow-info.outputs.pullRequestNumber }} | wc -l)"
+          git checkout $BASE
+
+          EXISTS=$(git ls-remote --heads origin lean-pr-testing-${{ steps.workflow-info.outputs.pullRequestNumber }} | wc -l)
           echo "Branch exists: $EXISTS"
           if [ "$EXISTS" = "0" ]; then
             echo "Branch does not exist, creating it."
-            git switch -c lean-pr-testing-${{ steps.workflow-info.outputs.pullRequestNumber }} "$BASE"
+            git checkout -b lean-pr-testing-${{ steps.workflow-info.outputs.pullRequestNumber }}
             echo "leanprover/lean4-pr-releases:pr-release-${{ steps.workflow-info.outputs.pullRequestNumber }}" > lean-toolchain
             git add lean-toolchain
-            sed -i "s/require batteries from git \"https:\/\/github.com\/leanprover-community\/batteries\" @ \".\+\"/require batteries from git \"https:\/\/github.com\/leanprover-community\/batteries\" @ \"nightly-testing-${MOST_RECENT_NIGHTLY}\"/" lakefile.lean
-            lake update batteries
-            git add lakefile.lean lake-manifest.json
             git commit -m "Update lean-toolchain for testing https://github.com/leanprover/lean4/pull/${{ steps.workflow-info.outputs.pullRequestNumber }}"
           else
             echo "Branch already exists, pushing an empty commit."
-            git switch lean-pr-testing-${{ steps.workflow-info.outputs.pullRequestNumber }}
-            # The Mathlib `nightly-testing` branch or `nightly-testing-YYYY-MM-DD` tag may have moved since this branch was created, so merge their changes.
-            # (This should no longer be possible once `nightly-testing-YYYY-MM-DD` is a tag, but it is still safe to merge.)
-            git merge "$BASE" --strategy-option ours --no-commit --allow-unrelated-histories
+            git checkout lean-pr-testing-${{ steps.workflow-info.outputs.pullRequestNumber }}
+            # The Mathlib `nightly-testing` or `nightly-testing-YYYY-MM-DD` branch may have moved since this branch was created, so merge their changes.
+            git merge $BASE --strategy-option ours --no-commit --allow-unrelated-histories
             git commit --allow-empty -m "Trigger CI for https://github.com/leanprover/lean4/pull/${{ steps.workflow-info.outputs.pullRequestNumber }}"
           fi
 

.github/workflows/restart-on-label.yml

@@ -1,31 +0,0 @@
-name: Restart by label
-on:
-  pull_request_target:
-    types:
-      - unlabeled
-      - labeled
-jobs:
-  restart-on-label:
-    runs-on: ubuntu-latest
-    if: contains(github.event.label.name, 'merge-ci') || contains(github.event.label.name, 'release-ci')
-    steps:
-    - run: |
-        # Finding latest CI workflow run on current pull request
-        # (unfortunately cannot search by PR number, only base branch,
-        # and that is't even unique given PRs from forks, but the risk
-        # of confusion is low and the danger is mild)
-        run_id=$(gh run list -e pull_request -b "$head_ref" --workflow 'CI' --limit 1 \
-          --limit 1 --json databaseId --jq '.[0].databaseId')
-        echo "Run id: ${run_id}"
-        gh run view "$run_id"
-        echo "Cancelling (just in case)"
-        gh run cancel "$run_id" || echo "(failed)"
-        echo "Waiting for 10s"
-        sleep 10
-        echo "Rerunning"
-        gh run rerun "$run_id"
-      shell: bash
-      env:
-        head_ref: ${{ github.head_ref }}
-        GH_TOKEN: ${{ github.token }}
-        GH_REPO: ${{ github.repository }}

.github/workflows/update-stage0.yml

@@ -40,32 +40,18 @@ jobs:
       run: |
           git config --global user.name "Lean stage0 autoupdater"
           git config --global user.email "<>"
+    - if: env.should_update_stage0 == 'yes'
+      uses: DeterminateSystems/nix-installer-action@main
     # Would be nice, but does not work yet:
     # https://github.com/DeterminateSystems/magic-nix-cache/issues/39
     # This action does not run that often and building runs in a few minutes, so ok for now
     #- if: env.should_update_stage0 == 'yes'
     #  uses: DeterminateSystems/magic-nix-cache-action@v2
     - if: env.should_update_stage0 == 'yes'
-      name: Restore Build Cache
-      uses: actions/cache/restore@v3
+      name: Install Cachix
+      uses: cachix/cachix-action@v12
       with:
-        path: nix-store-cache
-        key: Nix Linux-nix-store-cache-${{ github.sha }}
-        # fall back to (latest) previous cache
-        restore-keys: |
-          Nix Linux-nix-store-cache
-    - if: env.should_update_stage0 == 'yes'
-      name: Further Set Up Nix Cache
-      shell: bash -euxo pipefail {0}
-      run: |
-        # Nix seems to mutate the cache, so make a copy
-        cp -r nix-store-cache nix-store-cache-copy || true
-    - if: env.should_update_stage0 == 'yes'
-      name: Install Nix
-      uses: DeterminateSystems/nix-installer-action@main
-      with:
-        extra-conf: |
-          substituters = file://${{ github.workspace }}/nix-store-cache-copy?priority=10&trusted=true https://cache.nixos.org  
+        name: lean4
     - if: env.should_update_stage0 == 'yes'
       run: nix run .#update-stage0-commit
     - if: env.should_update_stage0 == 'yes'

.gitignore

@@ -4,10 +4,8 @@
 *.lock
 .lake
 lake-manifest.json
-/build
-/src/lakefile.toml
-/tests/lakefile.toml
-/lakefile.toml
+build
+!/src/lake/Lake/Build
 GPATH
 GRTAGS
 GSYMS

CMakeLists.txt

@@ -78,10 +78,6 @@ add_custom_target(update-stage0
   COMMAND $(MAKE) -C stage1 update-stage0
   DEPENDS stage1)
 
-add_custom_target(update-stage0-commit
-  COMMAND $(MAKE) -C stage1 update-stage0-commit
-  DEPENDS stage1)
-
 add_custom_target(test
   COMMAND $(MAKE) -C stage1 test
   DEPENDS stage1)

CMakePresets.json

@@ -1,83 +0,0 @@
-{
-  "version": 2,
-  "cmakeMinimumRequired": {
-    "major": 3,
-    "minor": 10,
-    "patch": 0
-  },
-  "configurePresets": [
-    {
-      "name": "release",
-      "displayName": "Default development optimized build config",
-      "generator": "Unix Makefiles",
-      "binaryDir": "${sourceDir}/build/release"
-    },
-    {
-      "name": "debug",
-      "displayName": "Debug build config",
-      "cacheVariables": {
-        "CMAKE_BUILD_TYPE": "Debug"
-      },
-      "generator": "Unix Makefiles",
-      "binaryDir": "${sourceDir}/build/debug"
-    },
-    {
-      "name": "sanitize",
-      "displayName": "Sanitize build config",
-      "cacheVariables": {
-        "LEAN_EXTRA_CXX_FLAGS": "-fsanitize=address,undefined",
-        "LEANC_EXTRA_FLAGS": "-fsanitize=address,undefined -fsanitize-link-c++-runtime",
-        "SMALL_ALLOCATOR": "OFF",
-        "BSYMBOLIC": "OFF"
-      },
-      "generator": "Unix Makefiles",
-      "binaryDir": "${sourceDir}/build/sanitize"
-    },
-    {
-      "name": "sandebug",
-      "inherits": ["debug", "sanitize"],
-      "displayName": "Sanitize+debug build config",
-      "binaryDir": "${sourceDir}/build/sandebug"
-    }
-  ],
-  "buildPresets": [
-    {
-      "name": "release",
-      "configurePreset": "release"
-    },
-    {
-      "name": "debug",
-      "configurePreset": "debug"
-    },
-    {
-      "name": "sanitize",
-      "configurePreset": "sanitize"
-    },
-    {
-      "name": "sandebug",
-      "configurePreset": "sandebug"
-    }
-  ],
-  "testPresets": [
-    {
-      "name": "release",
-      "configurePreset": "release",
-      "output": {"outputOnFailure": true, "shortProgress": true}
-    },
-    {
-      "name": "debug",
-      "configurePreset": "debug",
-      "inherits": "release"
-    },
-    {
-      "name": "sanitize",
-      "configurePreset": "sanitize",
-      "inherits": "release"
-    },
-    {
-      "name": "sandebug",
-      "configurePreset": "sandebug",
-      "inherits": "release"
-    }
-  ]
-}

CODEOWNERS

@@ -6,40 +6,17 @@
 
 /.github/ @Kha @semorrison
 /RELEASES.md @semorrison
+/src/ @leodemoura @Kha
+/src/Init/IO.lean @joehendrix
 /src/kernel/ @leodemoura
 /src/lake/ @tydeu
 /src/Lean/Compiler/ @leodemoura
 /src/Lean/Data/Lsp/ @mhuisi
 /src/Lean/Elab/Deriving/ @semorrison
 /src/Lean/Elab/Tactic/ @semorrison
-/src/Lean/Language/ @Kha
 /src/Lean/Meta/Tactic/ @leodemoura
 /src/Lean/Parser/ @Kha
 /src/Lean/PrettyPrinter/ @Kha
-/src/Lean/PrettyPrinter/Delaborator/ @kmill
 /src/Lean/Server/ @mhuisi
 /src/Lean/Widget/ @Vtec234
-/src/Init/Data/ @semorrison
-/src/Init/Data/Array/Lemmas.lean @digama0
-/src/Init/Data/List/Lemmas.lean @digama0
-/src/Init/Data/List/BasicAux.lean @digama0
-/src/Init/Data/Array/Subarray.lean @david-christiansen
-/src/Lean/Elab/Tactic/RCases.lean @digama0
-/src/Init/RCases.lean @digama0
-/src/Lean/Elab/Tactic/Ext.lean @digama0
-/src/Init/Ext.lean @digama0
-/src/Lean/Elab/Tactic/Simpa.lean @digama0
-/src/Lean/Elab/Tactic/NormCast.lean @digama0
-/src/Lean/Meta/Tactic/NormCast.lean @digama0
-/src/Lean/Meta/Tactic/TryThis.lean @digama0
-/src/Lean/Elab/Tactic/SimpTrace.lean @digama0
-/src/Lean/Elab/Tactic/NoMatch.lean @digama0
-/src/Lean/Elab/Tactic/ShowTerm.lean @digama0
-/src/Lean/Elab/Tactic/Repeat.lean @digama0
-/src/Lean/Meta/Tactic/Repeat.lean @digama0
-/src/Lean/Meta/CoeAttr.lean @digama0
-/src/Lean/Elab/GuardMsgs.lean @digama0
-/src/Lean/Elab/Tactic/Guard.lean @digama0
-/src/Init/Guard.lean @digama0
-/src/Lean/Server/CodeActions/ @digama0
-
+/src/runtime/io.cpp @joehendrix

README.md

@@ -1,8 +1,13 @@
 This is the repository for **Lean 4**.
 
+We provide [nightly releases](https://github.com/leanprover/lean4-nightly/releases)
+and have just begun regular [stable point releases](https://github.com/leanprover/lean4/releases).
+
 # About
 
-- [Quickstart](https://lean-lang.org/lean4/doc/quickstart.html)
+- [Quickstart](https://github.com/leanprover/lean4/blob/master/doc/quickstart.md)
+- [Walkthrough installation video](https://www.youtube.com/watch?v=yZo6k48L0VY)
+- [Quick tour video](https://youtu.be/zyXtbb_eYbY)
 - [Homepage](https://lean-lang.org)
 - [Theorem Proving Tutorial](https://lean-lang.org/theorem_proving_in_lean4/)
 - [Functional Programming in Lean](https://lean-lang.org/functional_programming_in_lean/)
@@ -22,4 +27,4 @@ Please read our [Contribution Guidelines](CONTRIBUTING.md) first.
 
 # Building from Source
 
-See [Building Lean](https://lean-lang.org/lean4/doc/make/index.html) (documentation source: [doc/make/index.md](doc/make/index.md)).
+See [Building Lean](https://lean-lang.org/lean4/doc/make/index.html).

default.nix

@@ -0,0 +1,9 @@
+# used for `nix-shell https://github.com/leanprover/lean4/archive/master.tar.gz -A nix`
+{ nix = (import ./shell.nix {}).nix; } //
+(import (
+  fetchTarball {
+    url = "https://github.com/edolstra/flake-compat/archive/c75e76f80c57784a6734356315b306140646ee84.tar.gz";
+    sha256 = "071aal00zp2m9knnhddgr2wqzlx6i6qa1263lv1y7bdn2w20h10h"; }
+) {
+  src =  ./.;
+}).defaultNix

doc/BoolExpr.lean

@@ -1,4 +1,4 @@
-open Batteries
+open Std
 open Lean
 
 inductive BoolExpr where

doc/SUMMARY.md

@@ -89,6 +89,5 @@
 - [Testing](./dev/testing.md)
 - [Debugging](./dev/debugging.md)
 - [Commit Convention](./dev/commit_convention.md)
-- [Release checklist](./dev/release_checklist.md)
 - [Building This Manual](./dev/mdbook.md)
 - [Foreign Function Interface](./dev/ffi.md)

doc/char.md

@@ -1,11 +1 @@
 # Characters
-
-A value of type `Char`, also known as a character, is a [Unicode scalar value](https://www.unicode.org/glossary/#unicode_scalar_value). It is represented using an unsigned 32-bit integer and is statically guaranteed to be a valid Unicode scalar value.
-
-Syntactically, character literals are enclosed in single quotes.
-```lean
-#eval 'a' -- 'a'
-#eval '∀' -- '∀'
-```
-
-Characters are ordered and can be decidably compared using the relational operators `=`, `<`, `≤`, `>`, `≥`.

doc/declarations.md

@@ -483,43 +483,7 @@ def baz : Char → Nat
 | _   => 3
 ```
 
-The case where patterns are matched against an argument whose type is an inductive family is known as *dependent pattern matching*. This is more complicated, because the type of the function being defined can impose constraints on the patterns that are matched. In this case, the equation compiler will detect inconsistent cases and rule them out.
-
-```lean
-universe u
-
-inductive Vector (α : Type u) : Nat → Type u
-  | nil  : Vector α 0
-  | cons : α → Vector α n → Vector α (n+1)
-
-namespace Vector
-
-def head : Vector α (n+1) → α
-  | cons h t => h
-
-def tail : Vector α (n+1) → Vector α n
-  | cons h t => t
-
-def map (f : α → β → γ) : Vector α n → Vector β n → Vector γ n
-  | nil, nil => nil
-  | cons a va, cons b vb => cons (f a b) (map f va vb)
-
-end Vector
-```
-
-.. _recursive_functions:
-
-Recursive functions
-===================
-
-Lean must ensure that a recursive function terminates, for which there are two strategies: _structural recursion_, in which all recursive calls are made on smaller parts of the input data, and _well-founded recursion_, in which recursive calls are justified by showing that arguments to recursive calls are smaller according to some other measure.
-
-Structural recursion
---------------------
-
-If the definition of a function contains recursive calls, Lean first tries to interpret the definition as a structural recursion. In order for that to succeed, the recursive arguments must be subterms of the corresponding arguments on the left-hand side.
-
-The function is then defined using a *course of values* recursion, using automatically generated functions ``below`` and ``brec`` in the namespace corresponding to the inductive type of the recursive argument. In this case the defining equations hold definitionally, possibly with additional case splits.
+If any of the terms ``tᵢ`` in the template above contain a recursive call to ``foo``, the equation compiler tries to interpret the definition as a structural recursion. In order for that to succeed, the recursive arguments must be subterms of the corresponding arguments on the left-hand side. The function is then defined using a *course of values* recursion, using automatically generated functions ``below`` and ``brec`` in the namespace corresponding to the inductive type of the recursive argument. In this case the defining equations hold definitionally, possibly with additional case splits.
 
 ```lean
 namespace Hide
@@ -540,12 +504,7 @@ example : append [(1 : Nat), 2, 3] [4, 5] = [1, 2, 3, 4, 5] => rfl
 end Hide
 ```
 
-Well-founded recursion
----------------------
-
-If structural recursion fails, the equation compiler falls back on well-founded recursion. It tries to infer an instance of ``SizeOf`` for the type of each argument, and then tries to find a permutation of the arguments such that each recursive call is decreasing under the lexicographic order with respect to ``sizeOf`` measures.  Lean uses information in the local context, so you can often provide the relevant proof manually using ``have`` in the body of the definition.
-
-In the case of well-founded recursion, the equation used to declare the function holds only propositionally, but not definitionally, and can be accessed using ``unfold``, ``simp`` and ``rewrite`` with the function name (for example ``unfold foo`` or ``simp [foo]``, where ``foo`` is the function defined with well-founded recursion).
+If structural recursion fails, the equation compiler falls back on well-founded recursion. It tries to infer an instance of ``SizeOf`` for the type of each argument, and then show that each recursive call is decreasing under the lexicographic order of the arguments with respect to ``sizeOf`` measure. If it fails, the error message provides information as to the goal that Lean tried to prove. Lean uses information in the local context, so you can often provide the relevant proof manually using ``have`` in the body of the definition. In this case of well-founded recursion, the defining equations hold only propositionally, and can be accessed using ``simp`` and ``rewrite`` with the name ``foo``.
 
 ```lean
 namespace Hide
@@ -569,53 +528,9 @@ by rw [div]; rfl
 end Hide
 ```
 
-If Lean cannot find a permutation of the arguments for which all recursive calls are decreasing, it will print a table that contains, for every recursive call, which arguments Lean could prove to be decreasing. For example, a function with three recursive calls and four parameters might cause the following message to be printed
-
-```
-example.lean:37:0-43:31: error: Could not find a decreasing measure.
-The arguments relate at each recursive call as follows:
-(<, ≤, =: relation proved, ? all proofs failed, _: no proof attempted)
-           x1 x2 x3 x4
-1) 39:6-27  =  =  _  =
-2) 40:6-25  =  ?  _  <
-3) 41:6-25  <  _  _  _
-Please use `termination_by` to specify a decreasing measure.
-```
-
-This table should be read as follows:
-
- * In the first recursive call, in line 39, arguments 1, 2 and 4 are equal to the function's parameters.
- * The second recursive call, in line 40, has an equal first argument, a smaller fourth argument, and nothing could be inferred for the second argument.
- * The third recursive call, in line 41, has a decreasing first argument.
- * No other proofs were attempted, either because the parameter has a type without a non-trivial ``WellFounded`` instance (parameter 3), or because it is already clear that no decreasing measure can be found.
-
-
-Lean will print the termination argument it found if ``set_option showInferredTerminationBy true`` is set.
-
-If Lean does not find the termination argument, or if you want to be explicit, you can append a `termination_by` clause to the function definition, after the function's body, but before the `where` clause if present. It is of the form
-```
-termination_by e
-```
-where ``e`` is an expression that depends on the parameters of the function and should be decreasing at each recursive call. The type of `e` should be an instance of the class ``WellFoundedRelation``, which determines how to compare two values of that type.
-
-If ``f`` has parameters “after the ``:``” (for example when defining functions via patterns using `|`), then these can be brought into scope using the syntax
-```
-termination_by a₁ … aₙ => e
-```
-
-By default, Lean uses the tactic ``decreasing_tactic`` when proving that an argument is decreasing; see its documentation for how to globally extend it. You can also choose to use a different tactic for a given function definition with the clause
-```
-decreasing_by <tac>
-```
-which should come after ``termination_by`, if present.
-
-
 Note that recursive definitions can in general require nested recursions, that is, recursion on different arguments of ``foo`` in the template above. The equation compiler handles this by abstracting later arguments, and recursively defining higher-order functions to meet the specification.
 
-Mutual recursion
-----------------
-
-The equation compiler also allows mutual recursive definitions, with a syntax similar to that of [Mutual and Nested Inductive Definitions](#mutual-and-nested-inductive-definitions). Mutual definitions are always compiled using well-founded recursion, and so once again the defining equations hold only propositionally.
+The equation compiler also allows mutual recursive definitions, with a syntax similar to that of [Mutual and Nested Inductive Definitions](#mutual-and-nested-inductive-definitions). They are compiled using well-founded recursion, and so once again the defining equations hold only propositionally.
 
 ```lean
 mutual
@@ -672,31 +587,29 @@ def num_consts_lst : List Term → Nat
 end
 ```
 
-In a set of mutually recursive function, either all or no functions must have an explicit termination argument (``termination_by``). A change of the default termination tactic (``decreasing_by``) only affects the proofs about the recursive calls of that function, not the other functions in the group.
+The case where patterns are matched against an argument whose type is an inductive family is known as *dependent pattern matching*. This is more complicated, because the type of the function being defined can impose constraints on the patterns that are matched. In this case, the equation compiler will detect inconsistent cases and rule them out.
 
-```
-mutual
-theorem even_of_odd_succ : ∀ n, Odd (n + 1) → Even n
-| _, odd_succ n h => h
-termination_by n h => h
-decreasing_by decreasing_tactic
+```lean
+universe u
 
-theorem odd_of_even_succ : ∀ n, Even (n + 1) → Odd n
-| _, even_succ n h => h
-termination_by n h => h
-end
-```
+inductive Vector (α : Type u) : Nat → Type u
+| nil  : Vector α 0
+| cons : α → Vector α n → Vector α (n+1)
 
-Another way to express mutual recursion is using local function definitions in ``where`` or ``let rec`` clauses: these can be mutually recursive with each other and their containing function:
+namespace Vector
 
-```
-theorem even_of_odd_succ : ∀ n, Odd (n + 1) → Even n
-  | _, odd_succ n h => h
-termination_by n h => h
-  where
-    theorem odd_of_even_succ : ∀ n, Even (n + 1) → Odd n
-      | _, even_succ n h => h
-    termination_by n h => h
+def head {α : Type} : Vector α (n+1) → α
+| cons h t => h
+
+def tail {α : Type} : Vector α (n+1) → Vector α n
+| cons h t => t
+
+def map {α β γ : Type} (f : α → β → γ) :
+  ∀ {n}, Vector α n → Vector β n → Vector γ n
+| 0,   nil,       nil       => nil
+| n+1, cons a va, cons b vb => cons (f a b) (map f va vb)
+
+end Vector
 ```
 
 .. _match_expressions:

doc/dev/bootstrap.md

@@ -75,28 +75,26 @@ The github repository will automatically update stage0 on `master` once
 
 If you have write access to the lean4 repository, you can also also manually
 trigger that process, for example to be able to use new features in the compiler itself.
-You can do that on <https://github.com/leanprover/lean4/actions/workflows/update-stage0.yml>
+You can do that on <https://github.com/nomeata/lean4/actions/workflows/update-stage0.yml>
 or using Github CLI with
 ```
 gh workflow run update-stage0.yml
 ```
 
-Leaving stage0 updates to the CI automation is preferable, but should you need
-to do it locally, you can use `make update-stage0-commit` in `build/release` to
-update `stage0` from `stage1` or `make -C stageN update-stage0-commit` to
-update from another stage. This command will automatically stage the updated files
-and introduce a commit,so make sure to commit your work before that.
-
-If you rebased the branch (either onto a newer version of `master`, or fixing
-up some commits prior to the stage0 update, recreate the stage0 update commits.
-The script `script/rebase-stage0.sh` can be used for that.
-
-The CI should prevent PRs with changes to stage0 (besides `stdlib_flags.h`)
-from entering `master` through the (squashing!) merge queue, and label such PRs
-with the `changes-stage0` label. Such PRs should have a cleaned up history,
-with separate stage0 update commits; then coordinate with the admins to merge
-your PR using rebase merge, bypassing the merge queue.
+Leaving stage0 updates to the CI automation is preferrable, but should you need
+to do it locally, you can use `make update-stage0` in `build/release`, to
+update `stage0` from `stage1`, `make -C stageN update-stage0` to update from
+another stage, or `nix run .#update-stage0-commit` to update using nix.
 
+Updates to `stage0` should be their own commits in the Git history. So should
+you have to include the stage0 update in your PR (rather than using above
+automation after merging changes), commit your work before running `make
+update-stage0`, commit the updated `stage0` compiler code with the commit
+message:
+```
+chore: update stage0
+```
+and coordinate with the admins to not squash your PR.
 
 ## Further Bootstrapping Complications
 

doc/dev/ffi.md

@@ -53,59 +53,10 @@ In the case of `@[extern]` all *irrelevant* types are removed first; see next se
   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.
+  Its runtime value is a pointer to an object of a subtype of `lean_object` (see respective declarations in `lean.h`) 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.
 
   Example: the runtime value of `u : Unit` is always `lean_box(0)`.
 
-#### Inductive types
-
-For inductive types which are in the fallback `lean_object *` case above and not trivial constructors, the type is stored as a `lean_ctor_object`, and `lean_is_ctor` will return true. A `lean_ctor_object` stores the constructor index in the header, and the fields are stored in the `m_objs` portion of the object.
-
-The memory order of the fields is derived from the types and order of the fields in the declaration. They are ordered as follows:
-
-* Non-scalar fields stored as `lean_object *`
-* Fields of type `USize`
-* Other scalar fields, in decreasing order by size
-
-Within each group the fields are ordered in declaration order. **Warning**: Trivial wrapper types still count toward a field being treated as non-scalar for this purpose.
-
-* To access fields of the first kind, use `lean_ctor_get(val, i)` to get the `i`th non-scalar field.
-* To access `USize` fields, use `lean_ctor_get_usize(val, n+i)` to get the `i`th usize field and `n` is the total number of fields of the first kind.
-* To access other scalar fields, use `lean_ctor_get_uintN(val, off)` or `lean_ctor_get_usize(val, off)` as appropriate. Here `off` is the byte offset of the field in the structure, starting at `n*sizeof(void*)` where `n` is the number of fields of the first two kinds.
-
-For example, a structure such as
-```lean
-structure S where
-  ptr_1 : Array Nat
-  usize_1 : USize
-  sc64_1 : UInt64
-  ptr_2 : { x : UInt64 // x > 0 } -- wrappers don't count as scalars
-  sc64_2 : Float -- `Float` is 64 bit
-  sc8_1 : Bool
-  sc16_1 : UInt16
-  sc8_2 : UInt8
-  sc64_3 : UInt64
-  usize_2 : USize
-  ptr_3 : Char -- trivial wrapper around `UInt32`
-  sc32_1 : UInt32
-  sc16_2 : UInt16
-```
-would get re-sorted into the following memory order:
-
-* `S.ptr_1` - `lean_ctor_get(val, 0)`
-* `S.ptr_2` - `lean_ctor_get(val, 1)`
-* `S.ptr_3` - `lean_ctor_get(val, 2)`
-* `S.usize_1` - `lean_ctor_get_usize(val, 3)`
-* `S.usize_2` - `lean_ctor_get_usize(val, 4)`
-* `S.sc64_1` - `lean_ctor_get_uint64(val, sizeof(void*)*5)`
-* `S.sc64_2` - `lean_ctor_get_float(val, sizeof(void*)*5 + 8)`
-* `S.sc64_3` - `lean_ctor_get_uint64(val, sizeof(void*)*5 + 16)`
-* `S.sc32_1` - `lean_ctor_get_uint32(val, sizeof(void*)*5 + 24)`
-* `S.sc16_1` - `lean_ctor_get_uint16(val, sizeof(void*)*5 + 28)`
-* `S.sc16_2` - `lean_ctor_get_uint16(val, sizeof(void*)*5 + 30)`
-* `S.sc8_1` - `lean_ctor_get_uint8(val, sizeof(void*)*5 + 32)`
-* `S.sc8_2` - `lean_ctor_get_uint8(val, sizeof(void*)*5 + 33)`
-
 ### Borrowing
 
 By default, all `lean_object *` parameters of an `@[extern]` function are considered *owned*, i.e. the external code is passed a "virtual RC token" and is responsible for passing this token along to another consuming function (exactly once) or freeing it via `lean_dec`.
@@ -160,15 +111,6 @@ if (lean_io_result_is_ok(res)) {
 lean_io_mark_end_initialization();
 ```
 
-In addition, any other thread not spawned by the Lean runtime itself must be initialized for Lean use by calling
-```c
-void lean_initialize_thread();
-```
-and should be finalized in order to free all thread-local resources by calling
-```c
-void lean_finalize_thread();
-```
-
 ## `@[extern]` in the Interpreter
 
 The interpreter can run Lean declarations for which symbols are available in loaded shared libraries, which includes `@[extern]` declarations.
@@ -179,4 +121,4 @@ Thus to e.g. run `#eval` on such a declaration, you need to
 Note that it is not sufficient to load the foreign library containing the external symbol because the interpreter depends on code that is emitted for each `@[extern]` declaration.
 Thus it is not possible to interpret an `@[extern]` declaration in the same file.
 
-See [`tests/compiler/foreign`](https://github.com/leanprover/lean4/tree/master/tests/compiler/foreign/) for an example.
+See `tests/compiler/foreign` for an example.

doc/dev/index.md

@@ -74,9 +74,3 @@ Lean's build process uses [`ccache`](https://ccache.dev/) if it is
 installed to speed up recompilation of the generated C code. Without
 `ccache`, you'll likely spend more time than necessary waiting on
 rebuilds - it's a good idea to make sure it's installed.
-
-### `prelude`
-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`.

doc/dev/release_checklist.md

@@ -1,226 +0,0 @@
-# Releasing a stable version
-
-This checklist walks you through releasing a stable version.
-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 someone has written the first draft of the release blog post
-- `git checkout releases/v4.6.0`
-  (This branch should already exist, from the release candidates.)
-- `git pull`
-- In `src/CMakeLists.txt`, verify you see
-  - `set(LEAN_VERSION_MINOR 6)` (for whichever `6` is appropriate)
-  - `set(LEAN_VERSION_IS_RELEASE 1)`
-  - (both of these should already be in place from the release candidates)
-- It is possible that the `v4.6.0` section of `RELEASES.md` is out of sync between
-  `releases/v4.6.0` and `master`. This should be reconciled:
-  - Run `git diff master RELEASES.md`.
-  - You should expect to see additons on `master` in the `v4.7.0-rc1` section; ignore these.
-    (i.e. the new release notes for the upcoming release candidate).
-  - Reconcile discrepancies in the `v4.6.0` section,
-    usually via copy and paste and a commit to `releases/v4.6.0`.
-- `git tag v4.6.0`
-- `git push $REMOTE v4.6.0`, where `$REMOTE` is the upstream Lean repository (e.g., `origin`, `upstream`)
-- Now wait, while CI runs.
-  - You can monitor this at `https://github.com/leanprover/lean4/actions/workflows/ci.yml`,
-    looking for the `v4.6.0` tag.
-  - This step can take up to an hour.
-  - If you are intending to cut the next release candidate on the same day,
-    you may want to start on the release candidate checklist now.
-- Go to https://github.com/leanprover/lean4/releases and verify that the `v4.6.0` release appears.
-  - Edit the release notes on Github to select the "Set as the latest release".
-  - Copy and paste the Github release notes from the previous releases candidate for this version
-    (e.g. `v4.6.0-rc1`), and quickly sanity check.
-- Next, we will move a curated list of downstream repos to the latest stable release.
-  - For each of the repositories listed below:
-    - Make a PR to `master`/`main` changing the toolchain to `v4.6.0`
-      - Update the toolchain file
-      - In the Lakefile, if there are dependencies on specific version tags of dependencies that you've already pushed as part of this process, update them to the new tag.
-        If they depend on `main` or `master`, don't change this; you've just updated the dependency, so it will work and be saved in the manifest
-      - Run `lake update`
-      - The PR title should be "chore: bump toolchain to v4.6.0".
-    - Merge the PR once CI completes.
-    - 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:
-    - [lean4checker](https://github.com/leanprover/lean4checker)
-      - No dependencies
-      - Toolchain bump PR
-      - Create and push the tag
-      - Merge the tag into `stable`
-    - [Batteries](https://github.com/leanprover-community/batteries)
-      - No dependencies
-      - Toolchain bump PR
-      - Create and push the tag
-      - Merge the tag into `stable`
-    - [ProofWidgets4](https://github.com/leanprover-community/ProofWidgets4)
-      - Dependencies: `Batteries`
-      - Note on versions and branches:
-        - `ProofWidgets` uses a sequential version tagging scheme, e.g. `v0.0.29`,
-          which does not refer to the toolchain being used.
-        - Make a new release in this sequence after merging the toolchain bump PR.
-        - `ProofWidgets` does not maintain a `stable` branch.
-      - Toolchain bump PR
-      - Create and push the tag, following the version convention of the repository
-    - [Aesop](https://github.com/leanprover-community/aesop)
-      - Dependencies: `Batteries`
-      - Toolchain bump PR including updated Lake manifest
-      - 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
-    - [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
-    - [Mathlib](https://github.com/leanprover-community/mathlib4)
-      - Dependencies: `Aesop`, `ProofWidgets4`, `lean4checker`, `Batteries`, `doc-gen4`, `import-graph`
-      - 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. 
-        - 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`.
-          Coordinate with a Mathlib maintainer to get this merged.
-    - [REPL](https://github.com/leanprover-community/repl)
-      - Dependencies: `Mathlib` (for test code)
-      - Note that there are two copies of `lean-toolchain`/`lakefile.lean`:
-        in the root, and in `test/Mathlib/`. Edit both, and run `lake update` in both directories.
-      - Toolchain bump PR including updated Lake manifest
-      - Create and push the tag
-      - Merge the tag into `stable`
-- Merge the release announcement PR for the Lean website - it will be deployed automatically
-- Finally, make an announcement!
-  This should go in https://leanprover.zulipchat.com/#narrow/stream/113486-announce, with topic `v4.6.0`.
-  Please see previous announcements for suggested language.
-  You will want a few bullet points for main topics from the release notes.
-  Link to the blog post from the Zulip announcement.
-- Make sure that whoever is handling social media knows the release is out.
-
-## Optimistic(?) time estimates:
-- Initial checks and push the tag: 30 minutes.
-- Note that if `RELEASES.md` has discrepancies this could take longer!
-- Waiting for the release: 60 minutes.
-- Fixing release notes: 10 minutes.
-- Bumping toolchains in downstream repositories, up to creating the Mathlib PR: 30 minutes.
-- Waiting for Mathlib CI and bors: 120 minutes.
-- Finalizing Mathlib tags and stable branch, and updating REPL: 15 minutes.
-- Posting announcement and/or blog post: 20 minutes.
-
-# Creating a release candidate.
-
-This checklist walks you through creating the first release candidate for a version of Lean.
-
-We'll use `v4.7.0-rc1` as the intended release version in this example.
-
-- Decide which nightly release you want to turn into a release candidate.
-  We will use `nightly-2024-02-29` in this example.
-- It is essential that Batteries and Mathlib already have reviewed branches compatible with this nightly.
-  - Check that both Batteries and Mathlib's `bump/v4.7.0` branch contain `nightly-2024-02-29`
-    in their `lean-toolchain`.
-  - The steps required to reach that state are beyond the scope of this checklist, but see below!
-- Create the release branch from this nightly tag:
-    ```
-    git remote add nightly https://github.com/leanprover/lean4-nightly.git
-    git fetch nightly tag nightly-2024-02-29
-    git checkout nightly-2024-02-29
-    git checkout -b releases/v4.7.0
-    ```
-- In `RELEASES.md` remove `(development in progress)` from the `v4.7.0` section header.
-- Our current goal is to have written release notes only about major language features or breaking changes,
-  and to rely on automatically generated release notes for bugfixes and minor changes.
-  - Do not wait on `RELEASES.md` being perfect before creating the `release/v4.7.0` branch. It is essential to choose the nightly which will become the release candidate as early as possible, to avoid confusion.
-  - If there are major changes not reflected in `RELEASES.md` already, you may need to solicit help from the authors.
-  - Minor changes and bug fixes do not need to be documented in `RELEASES.md`: they will be added automatically on the Github release page.
-  - Commit your changes to `RELEASES.md`, and push.
-  - Remember that changes to `RELEASES.md` after you have branched `releases/v4.7.0` should also be cherry-picked back to `master`.
-- 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`
-- 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.
-- Once the release appears at https://github.com/leanprover/lean4/releases/
-  - Edit the release notes on Github to select the "Set as a pre-release box".
-  - Copy the section of `RELEASES.md` for this version into the Github release notes.
-  - Use the title "Changes since v4.6.0 (from RELEASES.md)"
-  - Then in the "previous tag" dropdown, select `v4.6.0`, and click "Generate release notes".
-  - This will add a list of all the commits since the last stable version.
-    - Delete anything already mentioned in the hand-written release notes above.
-    - Delete "update stage0" commits, and anything with a completely inscrutable commit message.
-    - Briefly rearrange the remaining items by category (e.g. `simp`, `lake`, `bug fixes`),
-      but for minor items don't put any work in expanding on commit messages.
-  - (How we want to release notes to look is evolving: please update this section if it looks wrong!)
-- Next, we will move a curated list of downstream repos to the release candidate.
-  - This assumes that there is already a *reviewed* branch `bump/v4.7.0` on each repository
-    containing the required adaptations (or no adaptations are required).
-    The preparation of this branch is beyond the scope of this document.
-  - For each of the target repositories:
-    - Checkout the `bump/v4.7.0` branch.
-    - Verify that the `lean-toolchain` is set to the nightly from which the release candidate was created.
-    - `git merge origin/master`
-    - Change the `lean-toolchain` to `leanprover/lean4:v4.7.0-rc1`
-    - In `lakefile.lean`, change any dependencies which were using `nightly-testing` or `bump/v4.7.0` branches
-      back to `master` or `main`, and run `lake update` for those dependencies.
-    - Run `lake build` to ensure that dependencies are found (but it's okay to stop it after a moment).
-    - `git commit`
-    - `git push`
-    - Open a PR from `bump/v4.7.0` to `master`, and either merge it yourself after CI, if appropriate,
-      or notify the maintainers that it is ready to go.
-    - Once this PR has been merged, tag `master` with `v4.7.0-rc1` and push this tag.
-  - We do this for the same list of repositories as for stable releases, see above.
-    As above, there are dependencies between these, and so the process above is iterative.
-    It greatly helps if you can merge the `bump/v4.7.0` PRs yourself!
-  - For Batteries/Aesop/Mathlib, which maintain a `nightly-testing` branch, make sure there is a tag
-    `nightly-testing-2024-02-29` with date corresponding to the nightly used for the release
-    (create it if not), and then on the `nightly-testing` branch `git reset --hard master`, and force push.
-- Make an announcement!
-  This should go in https://leanprover.zulipchat.com/#narrow/stream/113486-announce, with topic `v4.7.0-rc1`.
-  Please see previous announcements for suggested language.
-  You will want a few bullet points for main topics from the release notes.
-  Please also make sure that whoever is handling social media knows the release is out.
-- Begin the next development cycle (i.e. for `v4.8.0`) on the Lean repository, by making a PR that:
-  - Updates `src/CMakeLists.txt` to say `set(LEAN_VERSION_MINOR 8)`
-  - Removes `(in development)` from the section heading in `RELEASES.md` for `v4.7.0`,
-    and creates a new `v4.8.0 (in development)` section heading.
-
-## Time estimates:
-Slightly longer than the corresponding steps for a stable release.
-Similar process, but more things go wrong.
-In particular, updating the downstream repositories is significantly more work
-(because we need to merge existing `bump/v4.7.0` branches, not just update a toolchain).
-
-# Preparing `bump/v4.7.0` branches
-
-While not part of the release process per se,
-this is a brief summary of the work that goes into updating Batteries/Aesop/Mathlib to new versions.
-
-Please read https://leanprover-community.github.io/contribute/tags_and_branches.html
-
-* Each repo has an unreviewed `nightly-testing` branch that
-  receives commits automatically from `master`, and
-  has its toolchain updated automatically for every nightly.
-  (Note: the aesop branch is not automated, and is updated on an as needed basis.)
-  As a consequence this branch is often broken.
-  A bot posts in the (private!) "Mathlib reviewers" stream on Zulip about the status of these branches.
-* We fix the breakages by committing directly to `nightly-testing`: there is no PR process.
-  * This can either be done by the person managing this process directly,
-    or by soliciting assistance from authors of files, or generally helpful people on Zulip!
-* Each repo has a `bump/v4.7.0` which accumulates reviewed changes adapting to new versions.
-* Once `nightly-testing` is working on a given nightly, say `nightly-2024-02-15`, we:
-  * Make sure `bump/v4.7.0` is up to date with `master` (by merging `master`, no PR necessary)
-  * Create from `bump/v4.7.0` a `bump/nightly-2024-02-15` branch.
-  * In that branch, `git merge --squash nightly-testing` to bring across changes from `nightly-testing`.
-  * Sanity check changes, commit, and make a PR to `bump/v4.7.0` from the `bump/nightly-2024-02-15` branch.
-  * Solicit review, merge the PR into `bump/v4,7,0`.
-* It is always okay to merge in the following directions:
-  `master` -> `bump/v4.7.0` -> `bump/nightly-2024-02-15` -> `nightly-testing`.
-  Please remember to push any merges you make to intermediate steps!

doc/dev/testing.md

@@ -41,17 +41,17 @@ information is displayed. This option will show all test output.
 
 All these tests are included by [src/shell/CMakeLists.txt](https://github.com/leanprover/lean4/blob/master/src/shell/CMakeLists.txt):
 
-- [`tests/lean`](https://github.com/leanprover/lean4/tree/master/tests/lean/): contains tests that come equipped with a
-  .lean.expected.out file. The driver script [`test_single.sh`](https://github.com/leanprover/lean4/tree/master/tests/lean/test_single.sh) runs
+- `tests/lean`: contains tests that come equipped with a
+  .lean.expected.out file. The driver script `test_single.sh` runs
   each test and checks the actual output (*.produced.out) with the
   checked in expected output.
 
-- [`tests/lean/run`](https://github.com/leanprover/lean4/tree/master/tests/lean/run/): contains tests that are run through the lean
+- `tests/lean/run`: contains tests that are run through the lean
   command line one file at a time. These tests only look for error
   codes and do not check the expected output even though output is
   produced, it is ignored.
 
-- [`tests/lean/interactive`](https://github.com/leanprover/lean4/tree/master/tests/lean/interactive/): are designed to test server requests at a
+- `tests/lean/interactive`: are designed to test server requests at a
   given position in the input file. Each .lean file contains comments
   that indicate how to simulate a client request at that position.
   using a `--^` point to the line position. Example:
@@ -61,7 +61,7 @@ All these tests are included by [src/shell/CMakeLists.txt](https://github.com/le
     Bla.
       --^ textDocument/completion
     ```
-    In this example, the test driver [`test_single.sh`](https://github.com/leanprover/lean4/tree/master/tests/lean/interactive/test_single.sh) will simulate an
+    In this example, the test driver `test_single.sh` will simulate an
     auto-completion request at `Bla.`. The expected output is stored in
     a .lean.expected.out in the json format that is part of the
     [Language Server
@@ -78,21 +78,21 @@ All these tests are included by [src/shell/CMakeLists.txt](https://github.com/le
     --^ collectDiagnostics
     ```
 
-- [`tests/lean/server`](https://github.com/leanprover/lean4/tree/master/tests/lean/server/): Tests more of the Lean `--server` protocol.
+- `tests/lean/server`: Tests more of the Lean `--server` protocol.
   There are just a few of them, and it uses .log files containing
   JSON.
 
-- [`tests/compiler`](https://github.com/leanprover/lean4/tree/master/tests/compiler/): contains tests that will run the Lean compiler and
+- `tests/compiler`: contains tests that will run the Lean compiler and
   build an executable that is executed and the output is compared to
   the .lean.expected.out file. This test also contains a subfolder
-  [`foreign`](https://github.com/leanprover/lean4/tree/master/tests/compiler/foreign/) which shows how to extend Lean using C++.
+  `foreign` which shows how to extend Lean using C++.
 
-- [`tests/lean/trust0`](https://github.com/leanprover/lean4/tree/master/tests/lean/trust0): tests that run Lean in a mode that Lean doesn't
+- `tests/lean/trust0`: tests that run Lean in a mode that Lean doesn't
   even trust the .olean files (i.e., trust 0).
 
-- [`tests/bench`](https://github.com/leanprover/lean4/tree/master/tests/bench/): contains performance tests.
+- `tests/bench`: contains performance tests.
 
-- [`tests/plugin`](https://github.com/leanprover/lean4/tree/master/tests/plugin/): tests that compiled Lean code can be loaded into
+- `tests/plugin`: tests that compiled Lean code can be loaded into
   `lean` via the `--plugin` command line option.
 
 ## Writing Good Tests
@@ -103,7 +103,7 @@ Every test file should contain:
   and, if not 100% clear, why that is the desirable behavior
 
 At the time of writing, most tests do not follow these new guidelines yet.
-For an example of a conforming test, see [`tests/lean/1971.lean`](https://github.com/leanprover/lean4/tree/master/tests/lean/1971.lean).
+For an example of a conforming test, see `tests/lean/1971.lean`.
 
 ## Fixing Tests
 
@@ -119,7 +119,7 @@ First, we must install [meld](http://meldmerge.org/). On Ubuntu, we can do it by
 sudo apt-get install meld
 ```
 
-Now, suppose `bad_class.lean` test is broken. We can see the problem by going to [`tests/lean`](https://github.com/leanprover/lean4/tree/master/tests/lean) directory and
+Now, suppose `bad_class.lean` test is broken. We can see the problem by going to `tests/lean` directory and
 executing
 
 ```

doc/examples/Certora2022/ex8.lean

@@ -4,16 +4,16 @@ def ack : Nat → Nat → Nat
   | 0,   y   => y+1
   | x+1, 0   => ack x 1
   | x+1, y+1 => ack x (ack (x+1) y)
-termination_by x y => (x, y)
+termination_by ack x y => (x, y)
 
 def sum (a : Array Int) : Int :=
   let rec go (i : Nat) :=
-     if _ : i < a.size then
+     if i < a.size then
         a[i] + go (i+1)
      else
         0
-  termination_by a.size - i
   go 0
+termination_by go i => a.size - i
 
 set_option pp.proofs true
 #print sum.go

doc/examples/ICERM2022/ctor.lean

@@ -4,42 +4,43 @@ open Lean Meta
 
 def ctor (mvarId : MVarId) (idx : Nat) : MetaM (List MVarId) := do
   /- Set `MetaM` context using `mvarId` -/
-  mvarId.withContext do
+  withMVarContext mvarId do 
     /- Fail if the metavariable is already assigned. -/
-    mvarId.checkNotAssigned `ctor
+    checkNotAssigned mvarId `ctor
     /- Retrieve the target type, instantiateMVars, and use `whnf`. -/
-    let target ← mvarId.getType'
+    let target ← getMVarType' mvarId
     let .const declName us := target.getAppFn
       | throwTacticEx `ctor mvarId "target is not an inductive datatype"
     let .inductInfo { ctors, .. } ← getConstInfo declName
       | throwTacticEx `ctor mvarId "target is not an inductive datatype"
     if idx = 0 then
-      throwTacticEx `ctor mvarId "invalid index, it must be > 0"
+      throwTacticEx `ctor mvarId "invalid index, it must be > 0"  
     else if h : idx - 1 < ctors.length then
-      mvarId.apply (.const ctors[idx - 1] us)
+      apply mvarId (.const ctors[idx - 1] us)
     else
-      throwTacticEx `ctor mvarId "invalid index, inductive datatype has only {ctors.length} contructors"
+      throwTacticEx `ctor mvarId "invalid index, inductive datatype has only {ctors.length} contructors"  
 
 open Elab Tactic
 
-elab "ctor" idx:num : tactic =>
+elab "ctor" idx:num : tactic => 
   liftMetaTactic (ctor · idx.getNat)
 
-example (p : Prop) : p := by
+example (p : Prop) : p := by 
   ctor 1 -- Error
 
-example (h : q) : p ∨ q := by
+example (h : q) : p ∨ q := by 
   ctor 0 -- Error
   exact h
 
-example (h : q) : p ∨ q := by
+example (h : q) : p ∨ q := by 
   ctor 3 -- Error
   exact h
 
-example (h : q) : p ∨ q := by
+example (h : q) : p ∨ q := by 
   ctor 2
   exact h
 
-example (h : q) : p ∨ q := by
+example (h : q) : p ∨ q := by 
   ctor 1
-  exact h -- Error
+  exact h -- Error 
+

doc/examples/ICERM2022/meta.lean

@@ -5,15 +5,15 @@ open Lean Meta
 def ex1 (declName : Name) : MetaM Unit := do
   let info ← getConstInfo declName
   IO.println s!"{declName} : {← ppExpr info.type}"
-  if let some val := info.value? then
+  if let some val := info.value? then 
     IO.println s!"{declName} : {← ppExpr val}"
-
+    
 #eval ex1 ``Nat
 
 def ex2 (declName : Name) : MetaM Unit := do
   let info ← getConstInfo declName
   trace[Meta.debug] "{declName} : {info.type}"
-  if let some val := info.value? then
+  if let some val := info.value? then 
     trace[Meta.debug] "{declName} : {val}"
 
 #eval ex2 ``Add.add
@@ -30,9 +30,9 @@ def ex3 (declName : Name) : MetaM Unit := do
       trace[Meta.debug] "{x} : {← inferType x}"
 
 def myMin [LT α] [DecidableRel (α := α) (·<·)] (a b : α) : α :=
-  if a < b then
+  if a < b then 
     a
-  else
+  else 
     b
 
 set_option trace.Meta.debug true in
@@ -40,7 +40,7 @@ set_option trace.Meta.debug true in
 
 def ex4 : MetaM Unit := do
   let nat := mkConst ``Nat
-  withLocalDeclD `a nat fun a =>
+  withLocalDeclD `a nat fun a => 
   withLocalDeclD `b nat fun b => do
     let e ← mkAppM ``HAdd.hAdd #[a, b]
     trace[Meta.debug] "{e} : {← inferType e}"
@@ -66,17 +66,15 @@ open Elab Term
 
 def ex5 : TermElabM Unit := do
   let nat := Lean.mkConst ``Nat
-  withLocalDeclD `a nat fun a => do
+  withLocalDeclD `a nat fun a => do 
   withLocalDeclD `b nat fun b => do
     let ab ← mkAppM ``HAdd.hAdd #[a, b]
-    let abStx ← exprToSyntax ab
-    let aStx ← exprToSyntax a
-    let stx ← `(fun x => if x < 10 then $abStx + x else x + $aStx)
+    let stx ← `(fun x => if x < 10 then $(← exprToSyntax ab) + x else x + $(← exprToSyntax a))
     let e ← elabTerm stx none
     trace[Meta.debug] "{e} : {← inferType e}"
     let e := mkApp e (mkNatLit 5)
     let e ← whnf e
     trace[Meta.debug] "{e}"
-
+       
 set_option trace.Meta.debug true in
 #eval ex5

doc/examples/NFM2022/nfm8.lean

@@ -4,16 +4,16 @@ def ack : Nat → Nat → Nat
   | 0,   y   => y+1
   | x+1, 0   => ack x 1
   | x+1, y+1 => ack x (ack (x+1) y)
-termination_by x y => (x, y)
+termination_by ack x y => (x, y)
 
 def sum (a : Array Int) : Int :=
   let rec go (i : Nat) :=
-     if _ : i < a.size then
+     if i < a.size then
         a[i] + go (i+1)
      else
         0
-  termination_by a.size - i
   go 0
+termination_by go i => a.size - i
 
 set_option pp.proofs true
 #print sum.go

doc/examples/bintree.lean

@@ -277,13 +277,14 @@ theorem BinTree.find_insert (b : BinTree β) (k : Nat) (v : β)
     . by_cases' key < k
       cases h; apply ihr; assumption
 
-theorem BinTree.find_insert_of_ne (b : BinTree β) (ne : k ≠ k') (v : β)
+theorem BinTree.find_insert_of_ne (b : BinTree β) (h : k ≠ k') (v : β)
         : (b.insert k v).find? k' = b.find? k' := by
   let ⟨t, h⟩ := b; simp
   induction t with simp
   | leaf =>
-    intros le
-    exact Nat.lt_of_le_of_ne le ne
+    split <;> (try simp) <;> split <;> (try simp)
+    have_eq k k'
+    contradiction
   | node left key value right ihl ihr =>
     let .node hl hr bl br := h
     specialize ihl bl

doc/examples/compiler/.gitignore

@@ -1 +0,0 @@
-build

doc/examples/palindromes.lean

@@ -82,7 +82,7 @@ theorem List.palindrome_ind (motive : List α → Prop)
     have ih := palindrome_ind motive h₁ h₂ h₃ (a₂::as').dropLast
     have : [a₁] ++ (a₂::as').dropLast ++ [(a₂::as').last (by simp)] = a₁::a₂::as' := by simp
     this ▸ h₃ _ _ _ ih
-termination_by as.length
+termination_by _ as => as.length
 
 /-!
 We use our new induction principle to prove that if `as.reverse = as`, then `Palindrome as` holds.

doc/examples/test_single.sh

@@ -1,4 +1,4 @@
 #!/usr/bin/env bash
 source ../../tests/common.sh
 
-exec_check lean -Dlinter.all=false "$f"
+exec_check lean -j 0 -Dlinter.all=false "$f"

doc/examples/widgets.lean

@@ -15,8 +15,9 @@ sections of a Lean document. User widgets are rendered in the Lean infoview.
 To try it out, simply type in the following code and place your cursor over the `#widget` command.
 -/
 
-@[widget_module]
-def helloWidget : Widget.Module where
+@[widget]
+def helloWidget : UserWidgetDefinition where
+  name := "Hello"
   javascript := "
     import * as React from 'react';
     export default function(props) {
@@ -24,7 +25,7 @@ def helloWidget : Widget.Module where
       return React.createElement('p', {}, name + '!')
     }"
 
-#widget helloWidget
+#widget helloWidget .null
 
 /-!
 If you want to dive into a full sample right away, check out
@@ -55,11 +56,7 @@ to the React component. In our first invocation of `#widget`, we set it to `.nul
 happens when you type in:
 -/
 
-structure HelloWidgetProps where
-  name? : Option String := none
-  deriving Server.RpcEncodable
-
-#widget helloWidget with { name? := "<your name here>" : HelloWidgetProps }
+#widget helloWidget (Json.mkObj [("name", "<your name here>")])
 
 /-!
 💡 NOTE: The RPC system presented below does not depend on JavaScript. However the primary use case
@@ -135,8 +132,9 @@ on this we either display an `InteractiveCode` with the type, `mapRpcError` the
 to turn it into a readable message, or show a `Loading..` message, respectively.
 -/
 
-@[widget_module]
-def checkWidget : Widget.Module where
+@[widget]
+def checkWidget : UserWidgetDefinition where
+  name := "#check as a service"
   javascript := "
 import * as React from 'react';
 const e = React.createElement;
@@ -162,7 +160,7 @@ export default function(props) {
 Finally we can try out the widget.
 -/
 
-#widget checkWidget
+#widget checkWidget .null
 
 /-!
 ![`#check` as a service](../images/widgets_caas.png)
@@ -195,8 +193,9 @@ interact with the text editor.
 You can see the full API for this [here](https://github.com/leanprover/vscode-lean4/blob/master/lean4-infoview-api/src/infoviewApi.ts#L52)
 -/
 
-@[widget_module]
-def insertTextWidget : Widget.Module where
+@[widget]
+def insertTextWidget : UserWidgetDefinition where
+  name := "textInserter"
   javascript := "
 import * as React from 'react';
 const e = React.createElement;
@@ -214,4 +213,4 @@ export default function(props) {
 
 /-! Finally, we can try this out: -/
 
-#widget insertTextWidget
+#widget insertTextWidget .null

doc/flake.lock

@@ -69,16 +69,15 @@
     "leanInk": {
       "flake": false,
       "locked": {
-        "lastModified": 1704976501,
-        "narHash": "sha256-FSBUsbX0HxakSnYRYzRBDN2YKmH9EkA0q9p7TSPEJTI=",
-        "owner": "leanprover",
+        "lastModified": 1666154782,
+        "narHash": "sha256-0ELqEca6jZT4BW/mqkDD+uYuxW5QlZUFlNwZkvugsg8=",
+        "owner": "digama0",
         "repo": "LeanInk",
-        "rev": "51821e3c2c032c88e4b2956483899d373ec090c4",
+        "rev": "12a2aec9b5f4aa84e84fb01a9af1da00d8aaff4e",
         "type": "github"
       },
       "original": {
         "owner": "leanprover",
-        "ref": "refs/pull/57/merge",
         "repo": "LeanInk",
         "type": "github"
       }

doc/flake.nix

@@ -12,7 +12,7 @@
     flake = false;
   };
   inputs.leanInk = {
-    url = "github:leanprover/LeanInk/refs/pull/57/merge";
+    url = "github:leanprover/LeanInk";
     flake = false;
   };
 
@@ -27,7 +27,7 @@
         src = inputs.mdBook;
         cargoDeps = drv.cargoDeps.overrideAttrs (_: {
           inherit src;
-          outputHash = "sha256-CO3A9Kpp4sIvkT9X3p+GTidazk7Fn4jf0AP2PINN44A=";
+          outputHash = "sha256-1YlPS6cqgxE4fjy9G8pWrpP27YrrbCDnfeyIsX81ZNw=";
         });
         doCheck = false;
       });

doc/functions.md

@@ -32,8 +32,8 @@ def fact x :=
 
 #eval fact 100
 ```
-By default, Lean only accepts total functions.
-The `partial` keyword may be used to define a recursive function without a termination proof; `partial` functions compute in compiled programs, but are opaque in proofs and during type checking.
+By default, Lean only accepts total functions. The `partial` keyword should be used when Lean cannot
+establish that a function always terminates.
 ```lean
 partial def g (x : Nat) (p : Nat -> Bool) : Nat :=
   if p x then

doc/latex/lean4.py

@@ -0,0 +1,100 @@
+# -*- coding: utf-8 -*-
+"""
+    pygments.lexers.theorem
+    ~~~~~~~~~~~~~~~~~~~~~~~
+
+    Lexers for theorem-proving languages.
+
+    :copyright: Copyright 2006-2017 by the Pygments team, see AUTHORS.
+    :license: BSD, see LICENSE for details.
+"""
+
+import re
+
+from pygments.lexer import RegexLexer, default, words
+from pygments.token import Text, Comment, Operator, Keyword, Name, String, \
+    Number, Punctuation, Generic
+
+__all__ = ['Lean4Lexer']
+
+class Lean4Lexer(RegexLexer):
+    """
+    For the `Lean 4 <https://github.com/leanprover/lean4>`_
+    theorem prover.
+
+    .. versionadded:: 2.0
+    """
+    name = 'Lean4'
+    aliases = ['lean4']
+    filenames = ['*.lean']
+    mimetypes = ['text/x-lean']
+
+    flags = re.MULTILINE | re.UNICODE
+
+    keywords1 = (
+        'import', 'abbreviation', 'opaque_hint', 'tactic_hint', 'definition',
+        'renaming', 'inline', 'hiding', 'parameter', 'lemma', 'variable',
+        'theorem', 'axiom', 'inductive', 'structure', 'universe', 'alias',
+        'help', 'options', 'precedence', 'postfix', 'prefix',
+        'infix', 'infixl', 'infixr', 'notation', '#eval',
+        '#check', '#reduce', '#exit', 'coercion', 'end', 'private', 'using', 'namespace',
+        'including', 'instance', 'section', 'context', 'protected', 'expose',
+        'export', 'set_option', 'extends', 'open', 'example',
+        'constant', 'constants', 'print', 'opaque', 'reducible', 'irreducible',
+        'def', 'macro', 'elab', 'syntax', 'macro_rules', 'reduce', 'where',
+        'abbrev', 'noncomputable', 'class', 'attribute', 'synth', 'mutual',
+    )
+
+    keywords2 = (
+        'forall', 'fun', 'Pi', 'obtain', 'from', 'have', 'show', 'assume',
+        'take', 'let', 'if', 'else', 'then', 'by', 'in', 'with', 'begin',
+        'proof', 'qed', 'calc', 'match', 'nomatch', 'do', 'at',
+    )
+
+    keywords3 = (
+        # Sorts
+        'Type', 'Prop', 'Sort',
+    )
+
+    operators = (
+        u'!=', u'#', u'&', u'&&', u'*', u'+', u'-', u'/', u'@', u'!', u'`',
+        u'-.', u'->', u'.', u'..', u'...', u'::', u':>', u';', u';;', u'<',
+        u'<-', u'=', u'==', u'>', u'_', u'|', u'||', u'~', u'=>', u'<=', u'>=',
+        u'/\\', u'\\/', u'∀', u'Π', u'λ', u'↔', u'∧', u'∨', u'≠', u'≤', u'≥',
+        u'¬', u'⁻¹', u'⬝', u'▸', u'→', u'∃', u'ℕ', u'ℤ', u'≈', u'×', u'⌞',
+        u'⌟', u'≡', u'⟨', u'⟩',
+    )
+
+    punctuation = (u'(', u')', u':', u'{', u'}', u'[', u']', u'⦃', u'⦄',
+                   u':=', u',')
+
+    tokens = {
+        'root': [
+            (r'\s+', Text),
+            (r'/-', Comment, 'comment'),
+            (r'--.*?$', Comment.Single),
+            (words(keywords1, prefix=r'\b', suffix=r'\b'), Keyword.Namespace),
+            (words(keywords2, prefix=r'\b', suffix=r'\b'), Keyword),
+            (words(keywords3, prefix=r'\b', suffix=r'\b'), Keyword.Type),
+            (words(operators), Name.Builtin.Pseudo),
+            (words(punctuation), Operator),
+            (u"[A-Za-z_\u03b1-\u03ba\u03bc-\u03fb\u1f00-\u1ffe\u2100-\u214f]"
+             u"[A-Za-z_'\u03b1-\u03ba\u03bc-\u03fb\u1f00-\u1ffe\u2070-\u2079"
+             u"\u207f-\u2089\u2090-\u209c\u2100-\u214f0-9]*", Name),
+            (r'\d+', Number.Integer),
+            (r'"', String.Double, 'string'),
+            (r'[~?][a-z][\w\']*:', Name.Variable)
+        ],
+        'comment': [
+            # Multiline Comments
+            (r'[^/-]', Comment.Multiline),
+            (r'/-', Comment.Multiline, '#push'),
+            (r'-/', Comment.Multiline, '#pop'),
+            (r'[/-]', Comment.Multiline)
+        ],
+        'string': [
+            (r'[^\\"]+', String.Double),
+            (r'\\[n"\\]', String.Escape),
+            ('"', String.Double, '#pop'),
+        ],
+    }

doc/lexical_structure.md

@@ -8,7 +8,7 @@ A Lean program consists of a stream of UTF-8 tokens where each token
 is one of the following:
 
 ```
-   token: symbol | command | ident | string | raw_string | char | numeral |
+   token: symbol | command | ident | string | char | numeral |
         : decimal | doc_comment | mod_doc_comment | field_notation
 ```
 
@@ -94,22 +94,6 @@ So the complete syntax is:
    string_gap   : "\" newline whitespace*
 ```
 
-Raw String Literals
-===================
-
-Raw string literals are string literals without any escape character processing.
-They begin with `r##...#"` (with zero or more `#` characters) and end with `"#...##` (with the same number of `#` characters).
-The contents of a raw string literal may contain `"##..#` so long as the number of `#` characters
-is less than the number of `#` characters used to begin the raw string literal.
-
-```
-   raw_string          : raw_string_aux(0) | raw_string_aux(1) | raw_string_aux(2) | ...
-   raw_string_aux(n)   : 'r' '#'{n} '"' raw_string_item '"' '#'{n}
-   raw_string_item(n)  : raw_string_char | raw_string_quote(n)
-   raw_string_char     : [^"]
-   raw_string_quote(n) : '"' '#'{0..n-1}
-```
-
 Char Literals
 =============
 

doc/make/index.md

@@ -1,7 +1,3 @@
-These are instructions to set up a working development environment for those who wish to make changes to Lean itself. It is part of the [Development Guide](doc/dev/index.md).
-
-We strongly suggest that new users instead follow the [Quickstart](doc/quickstart.md) to get started using Lean, since this sets up an environment that can automatically manage multiple Lean toolchain versions, which is necessary when working within the Lean ecosystem.
-
 Requirements
 ------------
 
@@ -14,34 +10,47 @@ Platform-Specific Setup
 
 - [Linux (Ubuntu)](ubuntu.md)
 - [Windows (msys2)](msys2.md)
+- [Windows (Visual Studio)](msvc.md)
 - [Windows (WSL)](wsl.md)
 - [macOS (homebrew)](osx-10.9.md)
-- Linux/macOS/WSL via [Nix](https://nixos.org/nix/): Call `nix develop` in the project root. That's it.
+- Linux/macOS/WSL via [Nix](https://nixos.org/nix/): Call `nix-shell` in the project root. That's it.
 
 Generic Build Instructions
 --------------------------
 
-Setting up a basic parallelized release build:
+Setting up a basic release build:
 
 ```bash
-git clone https://github.com/leanprover/lean4
+git clone https://github.com/leanprover/lean4 --recurse-submodules
 cd lean4
-cmake --preset release
-make -C build/release -j$(nproc)  # see below for macOS
+mkdir -p build/release
+cd build/release
+cmake ../..
+make
 ```
-You can replace `$(nproc)`, which is not available on macOS and some alternative shells, with the desired parallelism amount.
+
+For regular development, we recommend running
+```bash
+git config submodule.recurse true
+```
+in the checkout so that `--recurse-submodules` doesn't have to be
+specified with `git pull/checkout/...`.
 
 The above commands will compile the Lean library and binaries into the
-`stage1` subfolder; see below for details.
+`stage1` subfolder; see below for details. Add `-j N` for an
+appropriate `N` to `make` for a parallel build.
 
-You should not usually run `cmake --install` after a successful build.
+For example, on an AMD Ryzen 9 `make` takes 00:04:55, whereas `make -j 10`
+takes 00:01:38.  Your results may vary depending on the speed of your hard
+drive.
+
+You should not usually run `make install` after a successful build.
 See [Dev setup using elan](../dev/index.md#dev-setup-using-elan) on how to properly set up your editor to use the correct stage depending on the source directory.
 
 Useful CMake Configuration Settings
 -----------------------------------
 
-Pass these along with the `cmake --preset release` command.
-There are also two alternative presets that combine some of these options you can use instead of `release`: `debug` and `sandebug` (sanitize + debug).
+Pass these along with the `cmake ../..` command.
 
 * `-D CMAKE_BUILD_TYPE=`\
   Select the build type. Valid values are `RELEASE` (default), `DEBUG`,

doc/make/msvc.md

@@ -0,0 +1,39 @@
+# Compiling Lean with Visual Studio
+
+WARNING: Compiling Lean with Visual Studio doesn't currently work.
+There's an ongoing effort to port Lean to Visual Studio.
+The instructions below are for VS 2017.
+
+In the meantime you can use [MSYS2](msys2.md) or [WSL](wsl.md).
+
+## Installing dependencies
+
+First, install `vcpkg` from https://github.com/Microsoft/vcpkg if you haven't
+done so already.
+Then, open a console in the directory you cloned `vcpkg` to, and type:
+`vcpkg install mpir` for the 32-bit library or
+`vcpkg install mpir:x64-windows` for the x64 one.
+
+In Visual Studio, use the "open folder" feature and open the Lean directory.
+Go to the `CMake->Change CMake Settings` menu. File `CMakeSettings.json` opens.
+In each of the targets, add the following snippet (i.e., after every
+`ctestCommandArgs`):
+
+```json
+    "variables": [
+      {
+        "name": "CMAKE_TOOLCHAIN_FILE",
+        "value": "C:\\path\\to\\vcpkg\\scripts\\buildsystems\\vcpkg.cmake"
+      }
+    ]
+```
+
+## Enable Intellisense
+
+In Visual Studio, press Ctrl+Q and type `CppProperties.json` and press Enter.
+Ensure `includePath` variables include `"${workspaceRoot}\\src"`.
+
+
+## Build Lean
+
+Press F7.

doc/make/msys2.md

@@ -38,9 +38,10 @@ cmake --version
 Then follow the [generic build instructions](index.md) in the MSYS2
 MinGW shell, using:
 ```
-cmake --preset release -DCMAKE_C_COMPILER=clang -DCMAKE_CXX_COMPILER=clang++
+cmake ../.. -G "Unix Makefiles"  -DCMAKE_C_COMPILER=clang -DCMAKE_CXX_COMPILER=clang++
 ```
-instead of `cmake --preset release`. This will use the clang compiler instead of gcc, which is required with msys2.
+instead of `cmake ../..`. This ensures that cmake will call `sh` instead of `cmd.exe`
+for script tasks and it will use the clang compiler instead of gcc, which is required.
 
 ## Install lean
 

doc/make/osx-10.9.md

@@ -1,4 +1,4 @@
-# Install Packages on OS X 14.5
+# Install Packages on OS X 10.9
 
 We assume that you are using [homebrew][homebrew] as a package manager.
 
@@ -22,7 +22,7 @@ brew install gcc
 ```
 To install clang++-3.5 via homebrew, please execute:
 ```bash
-brew install llvm
+brew install llvm --with-clang --with-asan
 ```
 To use compilers other than the default one (Apple's clang++), you
 need to use `-DCMAKE_CXX_COMPILER` option to specify the compiler

doc/metaprogramming-arith.md

@@ -60,7 +60,7 @@ While parsing `a * (b + c)`, `(b + c)` is assigned a precedence `60` by the addi
 the right argument to have precedence **at least** 71. Thus, this parse is invalid. In contrast, `(a * b) + c` assigns
 a precedence of `70` to `(a * b)`. This is compatible with addition which expects the left argument to have precedence
 **at least `60` ** (`70` is greater than `60`). Thus, the string `a * b + c` is parsed as `(a * b) + c`.
-For more details, please look at the [Lean manual on syntax extensions](./notation.md#notations-and-precedence).
+For more details, please look at the [Lean manual on syntax extensions](../syntax.md#notations-and-precedence).
 
 To go from strings into `Arith`, we define a macro to
 translate the syntax category `arith` into an `Arith` inductive value that

doc/monads/except.lean

@@ -33,7 +33,7 @@ convert the pure non-monadic value `x / y` into the required `Except` object.  S
 
 Now this return typing would get tedious if you had to include it everywhere that you call this
 function, however, Lean type inference can clean this up. For example, you can define a test
-function that calls the `divide` function and you don't need to say anything here about the fact that
+function can calls the `divide` function and you don't need to say anything here about the fact that
 it might throw an error, because that is inferred:
 -/
 def test := divide 5 0

doc/monads/states.lean

@@ -15,7 +15,7 @@ data type containing several important pieces of information. First and foremost
 current player, and it has a random generator.
 -/
 
-open Batteries (HashMap)
+open Std (HashMap)
 abbrev TileIndex := Nat × Nat -- a 2D index
 
 inductive TileState where

doc/setup.md

@@ -2,21 +2,21 @@
 
 ### Tier 1
 
-Platforms built & tested by our CI, available as binary releases via elan (see below)
+Platforms built & tested by our CI, available as nightly releases via elan (see below)
 
 * x86-64 Linux with glibc 2.27+
 * x86-64 macOS 10.15+
-* aarch64 (Apple Silicon) macOS 10.15+
 * x86-64 Windows 10+
 
 ### Tier 2
 
-Platforms cross-compiled but not tested by our CI, available as binary releases
+Platforms cross-compiled but not tested by our CI, available as nightly releases
 
 Releases may be silently broken due to the lack of automated testing.
 Issue reports and fixes are welcome.
 
 * aarch64 Linux with glibc 2.27+
+* aarch64 (Apple Silicon) macOS
 * x86 (32-bit) Linux
 * Emscripten Web Assembly
 
@@ -50,10 +50,10 @@ Foo.lean       # main file, import via `import Foo`
 Foo/
   A.lean       # further files, import via e.g. `import Foo.A`
   A/...        # further nesting
-.lake/         # `lake` build output directory
+build/         # `lake` build output directory
 ```
 
-After running `lake build` you will see a binary named `./.lake/build/bin/foo` and when you run it you should see the output:
+After running `lake build` you will see a binary named `./build/bin/foo` and when you run it you should see the output:
 ```
 Hello, world!
 ```

doc/syntax_highlight_in_latex.md

@@ -43,8 +43,7 @@ $ pdflatex test.tex
 
 ## Example with `minted`
 
-First [install Pygments](https://pygments.org/download/) (version 2.18 or newer).
-Then save the following sample LaTeX file `test.tex` into the same directory:
+First [install Pygments](https://pygments.org/download/). Then save [`lean4.py`](https://raw.githubusercontent.com/leanprover/lean4/master/doc/latex/lean4.py), which contains an version of the Lean highlighter updated for Lean 4, and the following sample LaTeX file `test.tex` into the same directory:
 
 ```latex
 \documentclass{article}
@@ -52,8 +51,9 @@ Then save the following sample LaTeX file `test.tex` into the same directory:
 % switch to a monospace font supporting more Unicode characters
 \setmonofont{FreeMono}
 \usepackage{minted}
-\newmintinline[lean]{lean4}{bgcolor=white}
-\newminted[leancode]{lean4}{fontsize=\footnotesize}
+% instruct minted to use our local theorem.py
+\newmintinline[lean]{lean4.py:Lean4Lexer -x}{bgcolor=white}
+\newminted[leancode]{lean4.py:Lean4Lexer -x}{fontsize=\footnotesize}
 \usemintedstyle{tango}  % a nice, colorful theme
 
 \begin{document}
@@ -67,6 +67,9 @@ theorem funext {f₁ f₂ : ∀ (x : α), β x} (h : ∀ x, f₁ x = f₂ x) : f
 \end{document}
 ```
 
+If your version of `minted` is v2.7 or newer, but before v3.0,
+you will additionally need to follow the workaround described in https://github.com/gpoore/minted/issues/360.
+
 You can then compile `test.tex` by executing the following command:
 
 ```bash
@@ -78,14 +81,11 @@ Some remarks:
  - either `xelatex` or `lualatex` is required to handle Unicode characters in the code.
  - `--shell-escape` is needed to allow `xelatex` to execute `pygmentize` in a shell.
  - If the chosen monospace font is missing some Unicode symbols, you can direct them to be displayed using a fallback font or other replacement LaTeX code.
-   ``` latex
-   \usepackage{newunicodechar}
-   \newfontfamily{\freeserif}{DejaVu Sans}
-   \newunicodechar{✝}{\freeserif{✝}}
-   \newunicodechar{𝓞}{\ensuremath{\mathcal{O}}}
-   ```
- - If you are using an old version of Pygments, you can copy 
-   [`lean.py`](https://raw.githubusercontent.com/pygments/pygments/master/pygments/lexers/lean.py) into your working directory,
-   and use `lean4.py:Lean4Lexer -x` instead of `lean4` above.
-   If your version of `minted` is v2.7 or newer, but before v3.0,
-   you will additionally need to follow the workaround described in https://github.com/gpoore/minted/issues/360.
+``` latex
+\usepackage{newunicodechar}
+\newfontfamily{\freeserif}{DejaVu Sans}
+\newunicodechar{✝}{\freeserif{✝}}
+\newunicodechar{𝓞}{\ensuremath{\mathcal{O}}}
+```
+ - minted has a "helpful" feature that draws red boxes around characters the chosen lexer doesn't recognize.
+ Since the Lean lexer cannot encompass all user-defined syntax, it is advisable to [work around](https://tex.stackexchange.com/a/343506/14563) this feature.

doc/tour.md

@@ -15,7 +15,7 @@ The most fundamental pieces of any Lean program are functions organized into nam
 [Functions](./functions.md) perform work on inputs to produce outputs,
 and they are organized under [namespaces](./namespaces.md),
 which are the primary way you group things in Lean.
-They are defined using the `def` command,
+They are defined using the [`def`](./definitions.md) command,
 which give the function a name and define its arguments.
 
 ```lean

doc/typeclass.md

@@ -99,11 +99,11 @@ Let us start with the first step of the program above, declaring an appropriate
 
 ```lean
 # namespace Ex
-class Inhabited (a : Sort u) where
+class Inhabited (a : Type u) where
   default : a
 
 #check @Inhabited.default
--- Inhabited.default : {a : Sort u} → [self : Inhabited a] → a
+-- Inhabited.default : {a : Type u} → [self : Inhabited a] → a
 # end Ex
 ```
 Note `Inhabited.default` doesn't have any explicit argument.
@@ -114,7 +114,7 @@ Now we populate the class with some instances:
 
 ```lean
 # namespace Ex
-# class Inhabited (a : Sort _) where
+# class Inhabited (a : Type _) where
 #  default : a
 instance : Inhabited Bool where
   default := true
@@ -138,7 +138,7 @@ instance : Inhabited Prop where
 You can use the command `export` to create the alias `default` for `Inhabited.default`
 ```lean
 # namespace Ex
-# class Inhabited (a : Sort _) where
+# class Inhabited (a : Type _) where
 #  default : a
 # instance : Inhabited Bool where
 #  default := true
@@ -174,7 +174,7 @@ instance [Inhabited a] [Inhabited b] : Inhabited (a × b) where
 With this added to the earlier instance declarations, type class instance can infer, for example, a default element of ``Nat × Bool``:
 ```lean
 # namespace Ex
-# class Inhabited (a : Sort u) where
+# class Inhabited (a : Type u) where
 #  default : a
 # instance : Inhabited Bool where
 #  default := true
@@ -191,14 +191,8 @@ instance [Inhabited a] [Inhabited b] : Inhabited (a × b) where
 ```
 Similarly, we can inhabit type function with suitable constant functions:
 ```lean
-# namespace Ex
-# class Inhabited (a : Sort u) where
-#  default : a
-# opaque default [Inhabited a] : a :=
-#  Inhabited.default
 instance [Inhabited b] : Inhabited (a -> b) where
   default := fun _ => default
-# end Ex
 ```
 As an exercise, try defining default instances for other types, such as `List` and `Sum` types.
 

doc/whatIsLean.md

@@ -37,6 +37,6 @@ Lean has numerous features, including:
 - [Extensible syntax](./syntax.md)
 - Hygienic macros
 - [Dependent types](https://lean-lang.org/theorem_proving_in_lean4/dependent_type_theory.html)
-- [Metaprogramming](./macro_overview.md)
+- [Metaprogramming](./metaprogramming.md)
 - Multithreading
 - Verification: you can prove properties of your functions using Lean itself

flake.lock

@@ -1,31 +1,12 @@
 {
   "nodes": {
-    "flake-compat": {
-      "flake": false,
-      "locked": {
-        "lastModified": 1673956053,
-        "narHash": "sha256-4gtG9iQuiKITOjNQQeQIpoIB6b16fm+504Ch3sNKLd8=",
-        "owner": "edolstra",
-        "repo": "flake-compat",
-        "rev": "35bb57c0c8d8b62bbfd284272c928ceb64ddbde9",
-        "type": "github"
-      },
-      "original": {
-        "owner": "edolstra",
-        "repo": "flake-compat",
-        "type": "github"
-      }
-    },
     "flake-utils": {
-      "inputs": {
-        "systems": "systems"
-      },
       "locked": {
-        "lastModified": 1710146030,
-        "narHash": "sha256-SZ5L6eA7HJ/nmkzGG7/ISclqe6oZdOZTNoesiInkXPQ=",
+        "lastModified": 1656928814,
+        "narHash": "sha256-RIFfgBuKz6Hp89yRr7+NR5tzIAbn52h8vT6vXkYjZoM=",
         "owner": "numtide",
         "repo": "flake-utils",
-        "rev": "b1d9ab70662946ef0850d488da1c9019f3a9752a",
+        "rev": "7e2a3b3dfd9af950a856d66b0a7d01e3c18aa249",
         "type": "github"
       },
       "original": {
@@ -37,11 +18,11 @@
     "lean4-mode": {
       "flake": false,
       "locked": {
-        "lastModified": 1709737301,
-        "narHash": "sha256-uT9JN2kLNKJK9c/S/WxLjiHmwijq49EgLb+gJUSDpz0=",
+        "lastModified": 1676498134,
+        "narHash": "sha256-u3WvyKxOViZG53hkb8wd2/Og6muTecbh+NdflIgVeyk=",
         "owner": "leanprover",
         "repo": "lean4-mode",
-        "rev": "f1f24c15134dee3754b82c9d9924866fe6bc6b9f",
+        "rev": "2c6ef33f476fdf5eb5e4fa4fa023ba8b11372440",
         "type": "github"
       },
       "original": {
@@ -50,35 +31,34 @@
         "type": "github"
       }
     },
-    "libgit2": {
+    "lowdown-src": {
       "flake": false,
       "locked": {
-        "lastModified": 1697646580,
-        "narHash": "sha256-oX4Z3S9WtJlwvj0uH9HlYcWv+x1hqp8mhXl7HsLu2f0=",
-        "owner": "libgit2",
-        "repo": "libgit2",
-        "rev": "45fd9ed7ae1a9b74b957ef4f337bc3c8b3df01b5",
+        "lastModified": 1633514407,
+        "narHash": "sha256-Dw32tiMjdK9t3ETl5fzGrutQTzh2rufgZV4A/BbxuD4=",
+        "owner": "kristapsdz",
+        "repo": "lowdown",
+        "rev": "d2c2b44ff6c27b936ec27358a2653caaef8f73b8",
         "type": "github"
       },
       "original": {
-        "owner": "libgit2",
-        "repo": "libgit2",
+        "owner": "kristapsdz",
+        "repo": "lowdown",
         "type": "github"
       }
     },
     "nix": {
       "inputs": {
-        "flake-compat": "flake-compat",
-        "libgit2": "libgit2",
+        "lowdown-src": "lowdown-src",
         "nixpkgs": "nixpkgs",
         "nixpkgs-regression": "nixpkgs-regression"
       },
       "locked": {
-        "lastModified": 1711102798,
-        "narHash": "sha256-CXOIJr8byjolqG7eqCLa+Wfi7rah62VmLoqSXENaZnw=",
+        "lastModified": 1657097207,
+        "narHash": "sha256-SmeGmjWM3fEed3kQjqIAO8VpGmkC2sL1aPE7kKpK650=",
         "owner": "NixOS",
         "repo": "nix",
-        "rev": "a22328066416650471c3545b0b138669ea212ab4",
+        "rev": "f6316b49a0c37172bca87ede6ea8144d7d89832f",
         "type": "github"
       },
       "original": {
@@ -89,33 +69,16 @@
     },
     "nixpkgs": {
       "locked": {
-        "lastModified": 1709083642,
-        "narHash": "sha256-7kkJQd4rZ+vFrzWu8sTRtta5D1kBG0LSRYAfhtmMlSo=",
+        "lastModified": 1653988320,
+        "narHash": "sha256-ZaqFFsSDipZ6KVqriwM34T739+KLYJvNmCWzErjAg7c=",
         "owner": "NixOS",
         "repo": "nixpkgs",
-        "rev": "b550fe4b4776908ac2a861124307045f8e717c8e",
+        "rev": "2fa57ed190fd6c7c746319444f34b5917666e5c1",
         "type": "github"
       },
       "original": {
         "owner": "NixOS",
-        "ref": "release-23.11",
-        "repo": "nixpkgs",
-        "type": "github"
-      }
-    },
-    "nixpkgs-old": {
-      "flake": false,
-      "locked": {
-        "lastModified": 1581379743,
-        "narHash": "sha256-i1XCn9rKuLjvCdu2UeXKzGLF6IuQePQKFt4hEKRU5oc=",
-        "owner": "NixOS",
-        "repo": "nixpkgs",
-        "rev": "34c7eb7545d155cc5b6f499b23a7cb1c96ab4d59",
-        "type": "github"
-      },
-      "original": {
-        "owner": "NixOS",
-        "ref": "nixos-19.03",
+        "ref": "nixos-22.05-small",
         "repo": "nixpkgs",
         "type": "github"
       }
@@ -138,11 +101,11 @@
     },
     "nixpkgs_2": {
       "locked": {
-        "lastModified": 1710889954,
-        "narHash": "sha256-Pr6F5Pmd7JnNEMHHmspZ0qVqIBVxyZ13ik1pJtm2QXk=",
+        "lastModified": 1686089707,
+        "narHash": "sha256-LTNlJcru2qJ0XhlhG9Acp5KyjB774Pza3tRH0pKIb3o=",
         "owner": "NixOS",
         "repo": "nixpkgs",
-        "rev": "7872526e9c5332274ea5932a0c3270d6e4724f3b",
+        "rev": "af21c31b2a1ec5d361ed8050edd0303c31306397",
         "type": "github"
       },
       "original": {
@@ -157,23 +120,7 @@
         "flake-utils": "flake-utils",
         "lean4-mode": "lean4-mode",
         "nix": "nix",
-        "nixpkgs": "nixpkgs_2",
-        "nixpkgs-old": "nixpkgs-old"
-      }
-    },
-    "systems": {
-      "locked": {
-        "lastModified": 1681028828,
-        "narHash": "sha256-Vy1rq5AaRuLzOxct8nz4T6wlgyUR7zLU309k9mBC768=",
-        "owner": "nix-systems",
-        "repo": "default",
-        "rev": "da67096a3b9bf56a91d16901293e51ba5b49a27e",
-        "type": "github"
-      },
-      "original": {
-        "owner": "nix-systems",
-        "repo": "default",
-        "type": "github"
+        "nixpkgs": "nixpkgs_2"
       }
     }
   },

flake.nix

@@ -2,9 +2,6 @@
   description = "Lean interactive theorem prover";
 
   inputs.nixpkgs.url = "github:NixOS/nixpkgs/nixpkgs-unstable";
-  # old nixpkgs used for portable release with older glibc (2.27)
-  inputs.nixpkgs-old.url = "github:NixOS/nixpkgs/nixos-19.03";
-  inputs.nixpkgs-old.flake = false;
   inputs.flake-utils.url = "github:numtide/flake-utils";
   inputs.nix.url = "github:NixOS/nix";
   inputs.lean4-mode = {
@@ -20,43 +17,14 @@
   #  inputs.lean4-mode.follows = "lean4-mode";
   #};
 
-  outputs = { self, nixpkgs, nixpkgs-old, flake-utils, nix, lean4-mode, ... }@inputs: flake-utils.lib.eachDefaultSystem (system:
+  outputs = { self, nixpkgs, flake-utils, nix, lean4-mode, ... }@inputs: flake-utils.lib.eachDefaultSystem (system:
     let
       pkgs = import nixpkgs {
         inherit system;
         # for `vscode-with-extensions`
         config.allowUnfree = true;
       };
-      # An old nixpkgs for creating releases with an old glibc
-      pkgsDist-old = import nixpkgs-old { inherit system; };
-      # An old nixpkgs for creating releases with an old glibc
-      pkgsDist-old-aarch = import nixpkgs-old { localSystem.config = "aarch64-unknown-linux-gnu"; };
-
       lean-packages = pkgs.callPackage (./nix/packages.nix) { src = ./.; inherit nix lean4-mode; };
-
-      devShellWithDist = pkgsDist: pkgs.mkShell.override {
-          stdenv = pkgs.overrideCC pkgs.stdenv lean-packages.llvmPackages.clang;
-        } ({
-          buildInputs = with pkgs; [
-            cmake gmp ccache
-            lean-packages.llvmPackages.llvm  # llvm-symbolizer for asan/lsan
-            gdb
-            # TODO: only add when proven to not affect the flakification
-            #pkgs.python3
-            tree  # for CI
-          ];
-          # https://github.com/NixOS/nixpkgs/issues/60919
-          hardeningDisable = [ "all" ];
-          # more convenient `ctest` output
-          CTEST_OUTPUT_ON_FAILURE = 1;
-        } // pkgs.lib.optionalAttrs pkgs.stdenv.isLinux {
-          GMP = pkgsDist.gmp.override { withStatic = true; };
-          GLIBC = pkgsDist.glibc;
-          GLIBC_DEV = pkgsDist.glibc.dev;
-          GCC_LIB = pkgsDist.gcc.cc.lib;
-          ZLIB = pkgsDist.zlib;
-          GDB = pkgsDist.gdb;
-        });
     in {
       packages = lean-packages // rec {
         debug = lean-packages.override { debug = true; };
@@ -81,10 +49,7 @@
       };
       defaultPackage = lean-packages.lean-all;
 
-      # The default development shell for working on lean itself
-      devShells.default = devShellWithDist pkgs;
-      devShells.oldGlibc = devShellWithDist pkgsDist-old;
-      devShells.oldGlibcAArch = devShellWithDist pkgsDist-old-aarch;
+      inherit (lean-packages) devShell;
 
       checks.lean = lean-packages.test;
     }) // rec {

nix/bootstrap.nix

@@ -65,7 +65,12 @@ rec {
     installPhase = ''
       mkdir -p $out/bin $out/lib/lean
       mv bin/lean $out/bin/
-      mv lib/lean/*.{so,dylib} $out/lib/lean
+      mv lib/lean/libleanshared.* $out/lib/lean
+   '' + lib.optionalString stdenv.isDarwin ''
+      for lib in $(otool -L $out/bin/lean | tail -n +2 | cut -d' ' -f1); do
+        if [[ "$lib" == *lean* ]]; then install_name_tool -change "$lib" "$out/lib/lean/$(basename $lib)" $out/bin/lean; fi
+      done
+      otool -L $out/bin/lean
     '';
     meta.mainProgram = "lean";
   });
@@ -87,8 +92,7 @@ rec {
         leanFlags = [ "-DwarningAsError=true" ];
       } // args);
       Init' = build { name = "Init"; deps = []; };
-      Std' = build { name = "Std"; deps = [ Init' ]; };
-      Lean' = build { name = "Lean"; deps = [ Std' ]; };
+      Lean' = build { name = "Lean"; deps = [ Init' ]; };
       attachSharedLib = sharedLib: pkg: pkg // {
         inherit sharedLib;
         mods = mapAttrs (_: m: m // { inherit sharedLib; propagatedLoadDynlibs = []; }) pkg.mods;
@@ -96,8 +100,7 @@ rec {
     in (all: all // all.lean) rec {
       inherit (Lean) emacs-dev emacs-package vscode-dev vscode-package;
       Init = attachSharedLib leanshared Init';
-      Std = attachSharedLib leanshared Std' // { allExternalDeps = [ Init ]; };
-      Lean = attachSharedLib leanshared Lean' // { allExternalDeps = [ Std ]; };
+      Lean = attachSharedLib leanshared Lean' // { allExternalDeps = [ Init ]; };
       Lake = build {
         name = "Lake";
         src = src + "/src/lake";
@@ -111,40 +114,35 @@ rec {
         linkFlags = lib.optional stdenv.isLinux "-rdynamic";
         src = src + "/src/lake";
       };
-      stdlib = [ Init Std Lean Lake ];
+      stdlib = [ Init Lean Lake ];
       modDepsFiles = symlinkJoin { name = "modDepsFiles"; paths = map (l: l.modDepsFile) (stdlib ++ [ Leanc ]); };
       depRoots = symlinkJoin { name = "depRoots"; paths = map (l: l.depRoots) stdlib; };
       iTree = symlinkJoin { name = "ileans"; paths = map (l: l.iTree) stdlib; };
       Leanc = build { name = "Leanc"; src = lean-bin-tools-unwrapped.leanc_src; deps = stdlib; roots = [ "Leanc" ]; };
-      stdlibLinkFlags = "${lib.concatMapStringsSep " " (l: "-L${l.staticLib}") stdlib} -L${leancpp}/lib/lean";
-      libInit_shared = runCommand "libInit_shared" { buildInputs = [ stdenv.cc ]; libName = "libInit_shared${stdenv.hostPlatform.extensions.sharedLibrary}"; } ''
-        mkdir $out
-        touch empty.c
-        ${stdenv.cc}/bin/cc -shared -o $out/$libName empty.c
-      '';
+      stdlibLinkFlags = "-L${Init.staticLib} -L${Lean.staticLib} -L${Lake.staticLib} -L${leancpp}/lib/lean";
       leanshared = runCommand "leanshared" { buildInputs = [ stdenv.cc ]; libName = "libleanshared${stdenv.hostPlatform.extensions.sharedLibrary}"; } ''
         mkdir $out
         LEAN_CC=${stdenv.cc}/bin/cc ${lean-bin-tools-unwrapped}/bin/leanc -shared ${lib.optionalString stdenv.isLinux "-Wl,-Bsymbolic"} \
-          ${if stdenv.isDarwin then "-Wl,-force_load,${Init.staticLib}/libInit.a -Wl,-force_load,${Lean.staticLib}/libStd.a -Wl,-force_load,${Lean.staticLib}/libLean.a -Wl,-force_load,${leancpp}/lib/lean/libleancpp.a ${leancpp}/lib/libleanrt_initial-exec.a -lc++"
-            else "-Wl,--whole-archive -lInit -lStd -lLean -lleancpp ${leancpp}/lib/libleanrt_initial-exec.a -Wl,--no-whole-archive -lstdc++"} -lm ${stdlibLinkFlags} \
+          ${if stdenv.isDarwin then "-Wl,-force_load,${Init.staticLib}/libInit.a -Wl,-force_load,${Lean.staticLib}/libLean.a -Wl,-force_load,${leancpp}/lib/lean/libleancpp.a ${leancpp}/lib/libleanrt_initial-exec.a -lc++"
+            else "-Wl,--whole-archive -lInit -lLean -lleancpp ${leancpp}/lib/libleanrt_initial-exec.a -Wl,--no-whole-archive -lstdc++"} -lm ${stdlibLinkFlags} \
           $(${llvmPackages.libllvm.dev}/bin/llvm-config --ldflags --libs) \
           -o $out/$libName
       '';
       mods = foldl' (mods: pkg: mods // pkg.mods) {} stdlib;
       print-paths = Lean.makePrintPathsFor [] mods;
       leanc = writeShellScriptBin "leanc" ''
-        LEAN_CC=${stdenv.cc}/bin/cc ${Leanc.executable}/bin/leanc -I${lean-bin-tools-unwrapped}/include ${stdlibLinkFlags} -L${libInit_shared} -L${leanshared} "$@"
+        LEAN_CC=${stdenv.cc}/bin/cc ${Leanc.executable}/bin/leanc -I${lean-bin-tools-unwrapped}/include ${stdlibLinkFlags} -L${leanshared} "$@"
       '';
       lean = runCommand "lean" { buildInputs = lib.optional stdenv.isDarwin darwin.cctools; } ''
         mkdir -p $out/bin
-        ${leanc}/bin/leanc ${leancpp}/lib/lean.cpp.o ${libInit_shared}/* ${leanshared}/* -o $out/bin/lean
+        ${leanc}/bin/leanc ${leancpp}/lib/lean.cpp.o ${leanshared}/* -o $out/bin/lean
       '';
       # derivation following the directory layout of the "basic" setup, mostly useful for running tests
       lean-all = stdenv.mkDerivation {
         name = "lean-${desc}";
         buildCommand = ''
           mkdir -p $out/bin $out/lib/lean
-          ln -sf ${leancpp}/lib/lean/* ${lib.concatMapStringsSep " " (l: "${l.modRoot}/* ${l.staticLib}/*") (lib.reverseList stdlib)} ${libInit_shared}/* ${leanshared}/* $out/lib/lean/
+          ln -sf ${leancpp}/lib/lean/* ${lib.concatMapStringsSep " " (l: "${l.modRoot}/* ${l.staticLib}/*") (lib.reverseList stdlib)} ${leanshared}/* $out/lib/lean/
           # put everything in a single final derivation so `IO.appDir` references work
           cp ${lean}/bin/lean ${leanc}/bin/leanc ${Lake-Main.executable}/bin/lake $out/bin
           # NOTE: `lndir` will not override existing `bin/leanc`
@@ -152,9 +150,11 @@ rec {
         '';
         meta.mainProgram = "lean";
       };
-      cacheRoots = linkFarmFromDrvs "cacheRoots" ([
+      cacheRoots = linkFarmFromDrvs "cacheRoots" [
         stage0 lean leanc lean-all iTree modDepsFiles depRoots Leanc.src
-      ] ++ map (lib: lib.oTree) stdlib);
+        # .o files are not a runtime dependency on macOS because of lack of thin archives
+        Lean.oTree Lake.oTree
+      ];
       test = buildCMake {
         name = "lean-test-${desc}";
         realSrc = lib.sourceByRegex src [ "src.*" "tests.*" ];
@@ -169,17 +169,16 @@ rec {
           ln -sf ${lean-all}/* .
         '';
         buildPhase = ''
-          ctest --output-junit test-results.xml --output-on-failure -E 'leancomptest_(doc_example|foreign)' -j$NIX_BUILD_CORES
+          ctest --output-on-failure -E 'leancomptest_(doc_example|foreign)' -j$NIX_BUILD_CORES
         '';
         installPhase = ''
-          mkdir $out
-          mv test-results.xml $out
+          touch $out
         '';
       };
       update-stage0 =
-        let cTree = symlinkJoin { name = "cs"; paths = map (lib: lib.cTree) stdlib; }; in
+        let cTree = symlinkJoin { name = "cs"; paths = [ Init.cTree Lean.cTree ]; }; in
         writeShellScriptBin "update-stage0" ''
-          CSRCS=${cTree} CP_C_PARAMS="--dereference --no-preserve=all" ${src + "/script/lib/update-stage0"}
+          CSRCS=${cTree} CP_C_PARAMS="--dereference --no-preserve=all" ${src + "/script/update-stage0"}
         '';
       update-stage0-commit = writeShellScriptBin "update-stage0-commit" ''
         set -euo pipefail

nix/buildLeanPackage.nix

@@ -5,12 +5,12 @@ let lean-final' = lean-final; in
 lib.makeOverridable (
 { name, src, fullSrc ? src, srcPrefix ? "", srcPath ? "$PWD/${srcPrefix}",
   # Lean dependencies. Each entry should be an output of buildLeanPackage.
-  deps ? [ lean.Init lean.Std lean.Lean ],
+  deps ? [ lean.Lean ],
   # Static library dependencies. Each derivation `static` should contain a static library in the directory `${static}`.
   staticLibDeps ? [],
   # Whether to wrap static library inputs in a -Wl,--start-group [...] -Wl,--end-group to ensure dependencies are resolved.
   groupStaticLibs ? false,
-  # Shared library dependencies included at interpretation with --load-dynlib and linked to. Each derivation `shared` should contain a
+  # Shared library dependencies included at interpretation with --load-dynlib and linked to. Each derivation `shared` should contain a 
   # shared library at the path `${shared}/${shared.libName or shared.name}` and a name to link to like `-l${shared.linkName or shared.name}`.
   # These libs are also linked to in packages that depend on this one.
   nativeSharedLibs ? [],
@@ -88,9 +88,9 @@ with builtins; let
   allNativeSharedLibs =
     lib.unique (lib.flatten (nativeSharedLibs ++ (map (dep: dep.allNativeSharedLibs or []) allExternalDeps)));
 
-  # A flattened list of all static library dependencies: this and every dep module's explicitly provided `staticLibDeps`,
+  # A flattened list of all static library dependencies: this and every dep module's explicitly provided `staticLibDeps`, 
   # plus every dep module itself: `dep.staticLib`
-  allStaticLibDeps =
+  allStaticLibDeps = 
     lib.unique (lib.flatten (staticLibDeps ++ (map (dep: [dep.staticLib] ++ dep.staticLibDeps or []) allExternalDeps)));
 
   pathOfSharedLib = dep: dep.libPath or "${dep}/${dep.libName or dep.name}";
@@ -176,7 +176,7 @@ with builtins; let
       # make local "copy" so `drv`'s Nix store path doesn't end up in ccache's hash
       ln -s ${drv.c}/${drv.cPath} src.c
       # on the other hand, a debug build is pretty fast anyway, so preserve the path for gdb
-      leanc -c -o $out/$oPath $leancFlags -fPIC ${if debug then "${drv.c}/${drv.cPath} -g" else "src.c -O3 -DNDEBUG -DLEAN_EXPORTING"}
+      leanc -c -o $out/$oPath $leancFlags -fPIC ${if debug then "${drv.c}/${drv.cPath} -g" else "src.c -O3 -DNDEBUG"}
     '';
   };
   mkMod = mod: deps:

releases_drafts/README.md

@@ -1,22 +0,0 @@
-Draft release notes
--------------------
-
-This folder contains drafts of release notes for inclusion in `RELEASES.md`.
-During the process to create a release candidate, we look through all the commits that make up the release
-to prepare the release notes, and in that process we take these drafts into account.
-
-Guidelines:
-- You should prefer adding release notes to commit messages over adding anything to this folder.
-  A release note should briefly explain the impact of a change from a user's point of view.
-  Please mark these parts out with words such as **release notes** and/or **breaking changes**.
-- It is not necessary to add anything to this folder. It is meant for larger features that span multiple PRs,
-  or for anything that would be helpful when preparing the release notes that might be missed
-  by someone reading through the change log.
-- If the PR that adds a feature simultaneously adds a draft release note, including the PR number is not required
-  since it can be obtained from the git history for the file.
-
-When release notes are prepared, all the draft release notes are deleted from this folder.
-For release candidates beyond the first one, you can either update `RELEASE.md` directly
-or continue to add drafts.
-
-When a release is finalized, we will copy the completed release notes from `RELEASE.md` to the `master` branch.

releases_drafts/varCtorNameLint.md

@@ -1,45 +0,0 @@
-A new linter flags situations where a local variable's name is one of
-the argumentless constructors of its type. This can arise when a user either
-doesn't open a namespace or doesn't add a dot or leading qualifier, as
-in the following:
-
-````
-inductive Tree (α : Type) where
-  | leaf
-  | branch (left : Tree α) (val : α) (right : Tree α)
-
-def depth : Tree α → Nat
-  | leaf => 0
-````
-
-With this linter, the `leaf` pattern is highlighted as a local
-variable whose name overlaps with the constructor `Tree.leaf`.
-
-The linter can be disabled with `set_option linter.constructorNameAsVariable false`.
-
-Additionally, the error message that occurs when a name in a pattern that takes arguments isn't valid now suggests similar names that would be valid. This means that the following definition:
-
-```
-def length (list : List α) : Nat :=
-  match list with
-  | nil => 0
-  | cons x xs => length xs + 1
-```
-
-now results in the following warning:
-
-```
-warning: Local variable 'nil' resembles constructor 'List.nil' - write '.nil' (with a dot) or 'List.nil' to use the constructor.
-note: this linter can be disabled with `set_option linter.constructorNameAsVariable false`
-```
-
-and error:
-
-```
-invalid pattern, constructor or constant marked with '[match_pattern]' expected
-
-Suggestion: 'List.cons' is similar
-```
-
-
-#4301

script/apply.lean

@@ -1,8 +1,3 @@
-/-
-Copyright (c) 2022 Sebastian Ullrich. All rights reserved.
-Released under Apache 2.0 license as described in the file LICENSE.
-Authors: Sebastian Ullrich
--/
 import Lean.Runtime
 
 abbrev M := ReaderT IO.FS.Stream IO
@@ -21,7 +16,7 @@ def mkTypedefFn (i : Nat) : M Unit := do
   emit s!"typedef obj* (*fn{i})({args}); // NOLINT\n"
   emit s!"#define FN{i}(f) reinterpret_cast<fn{i}>(lean_closure_fun(f))\n"
 
-def genSeq (n : Nat) (f : Nat → String) (sep := ", ") : String :=
+def genSeq (n : Nat) (f : Nat → String) (sep := ", ") : String := 
   List.range n |>.map f |>.intersperse sep |> .join
 
 -- make string: "obj* a1, obj* a2, ..., obj* an"

script/collideProfiles.lean

@@ -1,28 +0,0 @@
-import Lean.Util.Profiler
-
-/-!
-
-Usage:
-```sh
-lean --run ./script/collideProfiles.lean **/*.lean.json ... > merged.json
-```
-
-Merges multiple `trace.profiler.output` profiles into a single one while deduplicating samples with
-the same stack. This is useful for building cumulative profiles of medium-to-large projects because
-Firefox Profiler cannot handle hundreds of tracks and the deduplication will also ensure that the
-profile is small enough for uploading.
-
-As ordering of samples is not meaningful after this transformation, only "Call Tree" and "Flame
-Graph" are useful for such profiles.
--/
-
-open Lean
-
-def main (args : List String) : IO Unit := do
-  let profiles ← args.toArray.mapM fun path => do
-    let json ← IO.FS.readFile ⟨path⟩
-    let profile ← IO.ofExcept $ Json.parse json
-    IO.ofExcept <| fromJson? profile
-  -- NOTE: `collide` should not be interpreted
-  let profile := Firefox.Profile.collide profiles
-  IO.println <| Json.compress <| toJson profile

script/issues_summary.sh

@@ -1,39 +0,0 @@
-#!/bin/bash
-
-# https://chat.openai.com/share/7469c7c3-aceb-4d80-aee5-62982e1f1538
-
-# Output CSV Header
-echo '"Issue URL","Title","Days Since Creation","Days Since Last Update","Total Reactions","Assignee","Labels"'
-
-# Get the current date in YYYY-MM-DD format
-today=$(date +%Y-%m-%d)
-
-# Fetch only open issues (excluding PRs and closed issues) from the repository 'leanprover/lean4'
-issues=$(gh api repos/leanprover/lean4/issues --paginate --jq '.[] | select(.pull_request == null and .state == "open") | {url: .html_url, title: .title, created_at: (.created_at | split("T")[0]), updated_at: (.updated_at | split("T")[0]), number: .number, assignee: (.assignee.login // ""), labels: [.labels[].name] | join(",")}')
-
-# Process each JSON object
-echo "$issues" | while IFS= read -r issue; do
-    # Extract fields from JSON
-    url=$(echo "$issue" | jq -r '.url')
-    title=$(echo "$issue" | jq -r '.title')
-    created_at=$(echo "$issue" | jq -r '.created_at')
-    updated_at=$(echo "$issue" | jq -r '.updated_at')
-    issue_number=$(echo "$issue" | jq -r '.number')
-    assignee=$(echo "$issue" | jq -r '.assignee')
-    labels=$(echo "$issue" | jq -r '.labels')
-
-    # Calculate days since creation and update using macOS compatible date calculation
-    days_since_created=$(( ($(date -jf "%Y-%m-%d" "$today" +%s) - $(date -jf "%Y-%m-%d" "$created_at" +%s)) / 86400 ))
-    days_since_updated=$(( ($(date -jf "%Y-%m-%d" "$today" +%s) - $(date -jf "%Y-%m-%d" "$updated_at" +%s)) / 86400 ))
-
-    # Fetch the total number of reactions for each issue
-    reaction_data=$(gh api repos/leanprover/lean4/issues/$issue_number/reactions --paginate --jq 'length' 2>&1)
-    if [[ $reaction_data == *"Not Found"* ]]; then
-        total_reactions="Error fetching reactions"
-    else
-        total_reactions=$reaction_data
-    fi
-
-    # Format output as CSV by escaping quotes and delimiting with commas
-    echo "\"$url\",\"${title//\"/\"\"}\",\"$days_since_created\",\"$days_since_updated\",\"$total_reactions\",\"$assignee\",\"$labels\""
-done

script/lib/README.md

@@ -1,2 +0,0 @@
-This directory contains various scripts that are *not* meant to be called
-directly, but through other scripts or makefiles.

script/lib/rebase-editor.sh

@@ -1,19 +0,0 @@
-#!/usr/bin/env bash
-
-
-# Script internal to `./script/rebase-stage0.sh`
-
-# Determine OS type for sed in-place editing
-SED_CMD=("sed" "-i")
-if [[ "$OSTYPE" == "darwin"* ]]
-then
-    # macOS requires an empty string argument with -i for in-place editing
-    SED_CMD=("sed" "-i" "")
-fi
-
-if [ "$STAGE0_WITH_NIX" = true ]
-then
-  "${SED_CMD[@]}" '/chore: update stage0/ s,.*,x nix run .#update-stage0-commit,' "$1"
-else
-  "${SED_CMD[@]}" '/chore: update stage0/ s,.*,x make -j32 -C build/release update-stage0 \&\& git commit -m "chore: update stage0",' "$1"
-fi

script/lib/update-stage0

@@ -1,33 +0,0 @@
-#!/usr/bin/env bash
-set -euo pipefail
-
-rm -r stage0 || true
-# don't copy untracked files
-# `:!` is git glob flavor for exclude patterns
-for f in $(git ls-files src ':!:src/lake/*' ':!:src/Leanc.lean'); do
-    if [[ $f == *.lean ]]; then
-        f=${f#src/}
-        f=${f%.lean}.c
-        mkdir -p $(dirname stage0/stdlib/$f)
-        cp ${CP_C_PARAMS:-} $CSRCS/$f stage0/stdlib/$f
-    else
-        mkdir -p $(dirname stage0/$f)
-        cp $f stage0/$f
-    fi
-done
-
-# special handling for Lake files due to its nested directory
-# copy the README to ensure the `stage0/src/lake` directory is comitted
-for f in $(git ls-files 'src/lake/Lake/*' src/lake/Lake.lean src/lake/README.md ':!:src/lakefile.toml'); do
-    if [[ $f == *.lean ]]; then
-        f=${f#src/lake}
-        f=${f%.lean}.c
-        mkdir -p $(dirname stage0/stdlib/$f)
-        cp ${CP_C_PARAMS:-} $CSRCS/$f stage0/stdlib/$f
-    else
-        mkdir -p $(dirname stage0/$f)
-        cp $f stage0/$f
-    fi
-done
-
-git add stage0

script/prepare-llvm-linux.sh

@@ -25,8 +25,6 @@ cp -L llvm/bin/llvm-ar stage1/bin/
 # dependencies of the above
 $CP llvm/lib/lib{clang-cpp,LLVM}*.so* stage1/lib/
 $CP $ZLIB/lib/libz.so* stage1/lib/
-# general clang++ dependency, breaks cross-library C++ exceptions if linked statically
-$CP $GCC_LIB/lib/libgcc_s.so* stage1/lib/
 # bundle libatomic (referenced by LLVM >= 15, and required by the lean executable to run)
 $CP $GCC_LIB/lib/libatomic.so* stage1/lib/
 
@@ -62,7 +60,7 @@ 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='-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 -Wl,--as-needed -Wl,-Bstatic -lgmp -lunwind -Wl,-Bdynamic -Wl,--no-as-needed -fuse-ld=lld'"
+echo -n " -DLEANC_INTERNAL_LINKER_FLAGS='-L ROOT/lib -L ROOT/lib/glibc ROOT/lib/glibc/libc_nonshared.a -Wl,--as-needed -static-libgcc -Wl,-Bstatic -lgmp -lunwind -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 -Wl,--no-as-needed'"
 # do not set `LEAN_CC` for tests

script/rebase-stage0.sh

@@ -1,24 +0,0 @@
-#!/usr/bin/env bash
-
-# This script rebases onto the given branch/commit, and updates
-# all `chore: update stage0` commits along the way.
-
-# Whether to use nix or make to update stage0
-if [ "$1" = "-nix" ]
-then
-   export STAGE0_WITH_NIX=true
-   shift
-fi
-
-# Check if an argument is provided
-if [ "$#" -eq 0 ]; then
-    echo "Usage: $0 [-nix] <options to git rebase -i>"
-    exit 1
-fi
-
-REPO_ROOT=$(git rev-parse --show-toplevel)
-
-# Run git rebase in interactive mode, but automatically edit the todo list
-# using the defined GIT_SEQUENCE_EDITOR command
-GIT_SEQUENCE_EDITOR="$REPO_ROOT/script/lib/rebase-editor.sh" git rebase -i "$@"
-

script/update-stage0

@@ -0,0 +1,18 @@
+#!/usr/bin/env bash
+set -euo pipefail
+
+rm -r stage0 || true
+# don't copy untracked files
+# `:!` is git glob flavor for exclude patterns
+for f in $(git ls-files src ':!:src/lake/*' ':!:src/Leanc.lean'); do
+    if [[ $f == *.lean ]]; then
+        f=${f#src/}
+        f=${f%.lean}.c
+        mkdir -p $(dirname stage0/stdlib/$f)
+        cp ${CP_C_PARAMS:-} $CSRCS/$f stage0/stdlib/$f
+    else
+        mkdir -p $(dirname stage0/$f)
+        cp $f stage0/$f
+    fi
+done
+git add stage0

shell.nix

@@ -0,0 +1,27 @@
+let
+  flake = (import ./default.nix);
+  flakePkgs = flake.packages.${builtins.currentSystem};
+in { pkgs ? flakePkgs.nixpkgs, pkgsDist ? pkgs }:
+# use `shell` as default
+(attribs: attribs.shell // attribs) rec {
+  shell = pkgs.mkShell.override {
+    stdenv = pkgs.overrideCC pkgs.stdenv flakePkgs.llvmPackages.clang;
+  } (rec {
+    buildInputs = with pkgs; [
+      cmake gmp ccache
+      flakePkgs.llvmPackages.llvm  # llvm-symbolizer for asan/lsan
+    ];
+    # https://github.com/NixOS/nixpkgs/issues/60919
+    hardeningDisable = [ "all" ];
+    # more convenient `ctest` output
+    CTEST_OUTPUT_ON_FAILURE = 1;
+  } // pkgs.lib.optionalAttrs pkgs.stdenv.isLinux {
+    GMP = pkgsDist.gmp.override { withStatic = true; };
+    GLIBC = pkgsDist.glibc;
+    GLIBC_DEV = pkgsDist.glibc.dev;
+    GCC_LIB = pkgsDist.gcc.cc.lib;
+    ZLIB = pkgsDist.zlib;
+    GDB = pkgsDist.gdb;
+  });
+  nix = flake.devShell.${builtins.currentSystem};
+}

src/CMakeLists.txt

@@ -9,7 +9,7 @@ endif()
 include(ExternalProject)
 project(LEAN CXX C)
 set(LEAN_VERSION_MAJOR 4)
-set(LEAN_VERSION_MINOR 10)
+set(LEAN_VERSION_MINOR 5)
 set(LEAN_VERSION_PATCH 0)
 set(LEAN_VERSION_IS_RELEASE 0)  # This number is 1 in the release revision, and 0 otherwise.
 set(LEAN_SPECIAL_VERSION_DESC "" CACHE STRING "Additional version description like 'nightly-2018-03-11'")
@@ -18,14 +18,6 @@ if (LEAN_SPECIAL_VERSION_DESC)
   string(APPEND LEAN_VERSION_STRING "-${LEAN_SPECIAL_VERSION_DESC}")
 endif()
 
-set(LEAN_PLATFORM_TARGET "" CACHE STRING "LLVM triple of the target platform")
-if (NOT LEAN_PLATFORM_TARGET)
-  # this may fail when the compiler is not clang, but this should only happen in local builds where
-  # the value of the variable is not of immediate relevance
-  execute_process(COMMAND ${CMAKE_C_COMPILER} --print-target-triple
-    OUTPUT_VARIABLE LEAN_PLATFORM_TARGET OUTPUT_STRIP_TRAILING_WHITESPACE)
-endif()
-
 set(LEAN_EXTRA_LINKER_FLAGS "" CACHE STRING "Additional flags used by the linker")
 set(LEAN_EXTRA_CXX_FLAGS "" CACHE STRING "Additional flags used by the C++ compiler")
 set(LEAN_TEST_VARS "LEAN_CC=${CMAKE_C_COMPILER}" CACHE STRING "Additional environment variables used when running tests")
@@ -73,7 +65,6 @@ option(USE_GMP "USE_GMP" ON)
 
 # development-specific options
 option(CHECK_OLEAN_VERSION "Only load .olean files compiled with the current version of Lean" OFF)
-option(USE_LAKE "Use Lake instead of lean.mk for building core libs from language server" OFF)
 
 set(LEAN_EXTRA_MAKE_OPTS  ""                           CACHE STRING "extra options to lean --make")
 set(LEANC_CC              ${CMAKE_C_COMPILER}          CACHE STRING "C compiler to use in `leanc`")
@@ -300,12 +291,13 @@ if(${CMAKE_SYSTEM_NAME} MATCHES "Darwin")
     cmake_path(GET ZLIB_LIBRARY PARENT_PATH ZLIB_LIBRARY_PARENT_PATH)
     string(APPEND LEANSHARED_LINKER_FLAGS " -L ${ZLIB_LIBRARY_PARENT_PATH}")
   endif()
-  string(APPEND TOOLCHAIN_STATIC_LINKER_FLAGS " -lleancpp -lInit -lLean -lleanrt")
+  string(APPEND LEANC_STATIC_LINKER_FLAGS " -lleancpp -lInit -lLean -lleanrt")
 elseif(${CMAKE_SYSTEM_NAME} MATCHES "Emscripten")
-  string(APPEND TOOLCHAIN_STATIC_LINKER_FLAGS " -lleancpp -lInit -lLean -lnodefs.js -lleanrt")
+  string(APPEND LEANC_STATIC_LINKER_FLAGS " -lleancpp -lInit -lLean -lnodefs.js -lleanrt")
 else()
-  string(APPEND TOOLCHAIN_STATIC_LINKER_FLAGS " -Wl,--start-group -lleancpp -lLean -Wl,--end-group -Wl,--start-group -lInit -lleanrt -Wl,--end-group")
+  string(APPEND LEANC_STATIC_LINKER_FLAGS " -Wl,--start-group -lleancpp -lLean -Wl,--end-group -Wl,--start-group -lInit -lleanrt -Wl,--end-group")
 endif()
+string(APPEND LEANC_STATIC_LINKER_FLAGS " -lLake")
 
 set(LEAN_CXX_STDLIB "-lstdc++" CACHE STRING "C++ stdlib linker flags")
 
@@ -313,17 +305,8 @@ if(${CMAKE_SYSTEM_NAME} MATCHES "Darwin")
   set(LEAN_CXX_STDLIB "-lc++")
 endif()
 
-string(APPEND TOOLCHAIN_STATIC_LINKER_FLAGS " ${LEAN_CXX_STDLIB} -lStd")
-string(APPEND TOOLCHAIN_SHARED_LINKER_FLAGS " ${LEAN_CXX_STDLIB}")
-
-# in local builds, link executables and not just dynlibs against C++ stdlib as well,
-# which is required for e.g. asan
-if(NOT LEAN_STANDALONE)
-  string(APPEND CMAKE_EXE_LINKER_FLAGS " ${LEAN_CXX_STDLIB}")
-endif()
-
-# flags for user binaries = flags for toolchain binaries + Lake
-string(APPEND LEANC_STATIC_LINKER_FLAGS " ${TOOLCHAIN_STATIC_LINKER_FLAGS} -lLake")
+string(APPEND LEANC_STATIC_LINKER_FLAGS " ${LEAN_CXX_STDLIB}")
+string(APPEND LEANSHARED_LINKER_FLAGS " ${LEAN_CXX_STDLIB}")
 
 if (LLVM)
   string(APPEND LEANSHARED_LINKER_FLAGS " -L${LLVM_CONFIG_LIBDIR} ${LLVM_CONFIG_LDFLAGS} ${LLVM_CONFIG_LIBS} ${LLVM_CONFIG_SYSTEM_LIBS}")
@@ -351,9 +334,9 @@ endif()
 
 # get rid of unused parts of C++ stdlib
 if(${CMAKE_SYSTEM_NAME} MATCHES "Darwin")
-  string(APPEND TOOLCHAIN_SHARED_LINKER_FLAGS " -Wl,-dead_strip")
+  string(APPEND LEANSHARED_LINKER_FLAGS " -Wl,-dead_strip")
 elseif(NOT ${CMAKE_SYSTEM_NAME} MATCHES "Emscripten")
-  string(APPEND TOOLCHAIN_SHARED_LINKER_FLAGS " -Wl,--gc-sections")
+  string(APPEND LEANSHARED_LINKER_FLAGS " -Wl,--gc-sections")
 endif()
 
 if(NOT ${CMAKE_SYSTEM_NAME} MATCHES "Darwin")
@@ -363,20 +346,26 @@ endif()
 if(${CMAKE_SYSTEM_NAME} MATCHES "Linux")
   if(BSYMBOLIC)
     string(APPEND LEANC_SHARED_LINKER_FLAGS " -Wl,-Bsymbolic")
-    string(APPEND TOOLCHAIN_SHARED_LINKER_FLAGS " -Wl,-Bsymbolic")
+    string(APPEND LEANSHARED_LINKER_FLAGS " -Wl,-Bsymbolic")
   endif()
   string(APPEND CMAKE_CXX_FLAGS " -fPIC -ftls-model=initial-exec")
   string(APPEND LEANC_EXTRA_FLAGS " -fPIC")
-  string(APPEND TOOLCHAIN_SHARED_LINKER_FLAGS " -Wl,-rpath=\\$$ORIGIN/..:\\$$ORIGIN")
-  string(APPEND CMAKE_EXE_LINKER_FLAGS " -Wl,-rpath=\\\$ORIGIN/../lib:\\\$ORIGIN/../lib/lean")
+  string(APPEND LEANSHARED_LINKER_FLAGS " -Wl,-rpath=\\$$ORIGIN/..:\\$$ORIGIN")
+  string(APPEND CMAKE_EXE_LINKER_FLAGS " -lleanshared -Wl,-rpath=\\\$ORIGIN/../lib:\\\$ORIGIN/../lib/lean")
 elseif(${CMAKE_SYSTEM_NAME} MATCHES "Darwin")
   string(APPEND CMAKE_CXX_FLAGS " -ftls-model=initial-exec")
-  string(APPEND INIT_SHARED_LINKER_FLAGS " -install_name @rpath/libInit_shared.dylib")
   string(APPEND LEANSHARED_LINKER_FLAGS " -install_name @rpath/libleanshared.dylib")
-  string(APPEND CMAKE_EXE_LINKER_FLAGS " -Wl,-rpath,@executable_path/../lib -Wl,-rpath,@executable_path/../lib/lean")
+  string(APPEND CMAKE_EXE_LINKER_FLAGS " -lleanshared -Wl,-rpath,@executable_path/../lib -Wl,-rpath,@executable_path/../lib/lean")
 elseif(${CMAKE_SYSTEM_NAME} MATCHES "Emscripten")
   string(APPEND CMAKE_CXX_FLAGS " -fPIC")
   string(APPEND LEANC_EXTRA_FLAGS " -fPIC")
+  # We do not use dynamic linking via leanshared for Emscripten to keep things
+  # simple. (And we are not interested in `Lake` anyway.) To use dynamic
+  # linking, we would probably have to set MAIN_MODULE=2 on `leanshared`,
+  # SIDE_MODULE=2 on `lean`, and set CMAKE_SHARED_LIBRARY_SUFFIX to ".js".
+  string(APPEND CMAKE_EXE_LINKER_FLAGS " -Wl,--whole-archive -lInit -lLean -lleancpp -lleanrt ${EMSCRIPTEN_SETTINGS} -lnodefs.js -s EXIT_RUNTIME=1 -s MAIN_MODULE=1 -s LINKABLE=1 -s EXPORT_ALL=1")
+elseif(${CMAKE_SYSTEM_NAME} MATCHES "Windows")
+  string(APPEND CMAKE_EXE_LINKER_FLAGS " -lleanshared")
 endif()
 
 if(${CMAKE_SYSTEM_NAME} MATCHES "Linux")
@@ -402,7 +391,7 @@ endif()
 # are already loaded) and probably fail unless we set up LD_LIBRARY_PATH.
 if(${CMAKE_SYSTEM_NAME} MATCHES "Windows")
   # import library created by the `leanshared` target
-  string(APPEND LEANC_SHARED_LINKER_FLAGS " -lInit_shared -lleanshared")
+  string(APPEND LEANC_SHARED_LINKER_FLAGS " -lleanshared")
 elseif("${CMAKE_SYSTEM_NAME}" MATCHES "Darwin")
   string(APPEND LEANC_SHARED_LINKER_FLAGS " -Wl,-undefined,dynamic_lookup")
 endif()
@@ -508,25 +497,13 @@ string(REGEX REPLACE "^([a-zA-Z]):" "/\\1" LEAN_BIN "${CMAKE_BINARY_DIR}/bin")
 # (also looks nicer in the build log)
 file(RELATIVE_PATH LIB ${LEAN_SOURCE_DIR} ${CMAKE_BINARY_DIR}/lib)
 
-# set up libInit_shared only on Windows; see also stdlib.make.in
-if(${CMAKE_SYSTEM_NAME} MATCHES "Windows")
-  set(INIT_SHARED_LINKER_FLAGS "-Wl,--whole-archive ${CMAKE_BINARY_DIR}/lib/temp/libInit.a.export ${CMAKE_BINARY_DIR}/runtime/libleanrt_initial-exec.a -Wl,--no-whole-archive -Wl,--out-implib,${CMAKE_BINARY_DIR}/lib/lean/libInit_shared.dll.a")
-endif()
-
 if(${CMAKE_SYSTEM_NAME} MATCHES "Darwin")
-  set(LEANSHARED_LINKER_FLAGS "-Wl,-force_load,${CMAKE_BINARY_DIR}/lib/lean/libInit.a -Wl,-force_load,${CMAKE_BINARY_DIR}/lib/lean/libStd.a -Wl,-force_load,${CMAKE_BINARY_DIR}/lib/lean/libLean.a -Wl,-force_load,${CMAKE_BINARY_DIR}/lib/lean/libleancpp.a ${CMAKE_BINARY_DIR}/runtime/libleanrt_initial-exec.a ${LEANSHARED_LINKER_FLAGS}")
-elseif(${CMAKE_SYSTEM_NAME} MATCHES "Windows")
-  set(LEANSHARED_LINKER_FLAGS "-Wl,--whole-archive ${CMAKE_BINARY_DIR}/lib/temp/libStd.a.export ${CMAKE_BINARY_DIR}/lib/temp/libLean.a.export -lleancpp -Wl,--no-whole-archive -lInit_shared -Wl,--out-implib,${CMAKE_BINARY_DIR}/lib/lean/libleanshared.dll.a")
+  set(LEANSHARED_LINKER_FLAGS "-Wl,-force_load,${CMAKE_BINARY_DIR}/lib/lean/libInit.a -Wl,-force_load,${CMAKE_BINARY_DIR}/lib/lean/libLean.a -Wl,-force_load,${CMAKE_BINARY_DIR}/lib/lean/libleancpp.a ${CMAKE_BINARY_DIR}/runtime/libleanrt_initial-exec.a ${LEANSHARED_LINKER_FLAGS}")
 else()
-  set(LEANSHARED_LINKER_FLAGS "-Wl,--whole-archive -lInit -lStd -lLean -lleancpp -Wl,--no-whole-archive ${CMAKE_BINARY_DIR}/runtime/libleanrt_initial-exec.a ${LEANSHARED_LINKER_FLAGS}")
-endif()
-
-if (${CMAKE_SYSTEM_NAME} MATCHES "Emscripten")
-  # We do not use dynamic linking via leanshared for Emscripten to keep things
-  # simple. (And we are not interested in `Lake` anyway.) To use dynamic
-  # linking, we would probably have to set MAIN_MODULE=2 on `leanshared`,
-  # SIDE_MODULE=2 on `lean`, and set CMAKE_SHARED_LIBRARY_SUFFIX to ".js".
-  string(APPEND LEAN_EXE_LINKER_FLAGS " ${TOOLCHAIN_STATIC_LINKER_FLAGS} ${EMSCRIPTEN_SETTINGS} -lnodefs.js -s EXIT_RUNTIME=1 -s MAIN_MODULE=1 -s LINKABLE=1 -s EXPORT_ALL=1")
+  set(LEANSHARED_LINKER_FLAGS "-Wl,--whole-archive -lInit -lLean -lleancpp -Wl,--no-whole-archive ${CMAKE_BINARY_DIR}/runtime/libleanrt_initial-exec.a ${LEANSHARED_LINKER_FLAGS}")
+  if(${CMAKE_SYSTEM_NAME} MATCHES "Windows")
+    string(APPEND LEANSHARED_LINKER_FLAGS " -Wl,--out-implib,${CMAKE_BINARY_DIR}/lib/lean/libleanshared.dll.a")
+  endif()
 endif()
 
 # Build the compiler using the bootstrapped C sources for stage0, and use
@@ -535,12 +512,16 @@ if (LLVM AND ${STAGE} GREATER 0)
   set(EXTRA_LEANMAKE_OPTS "LLVM=1")
 endif()
 
+# Escape for `make`. Yes, twice.
+string(REPLACE "$" "$$" CMAKE_EXE_LINKER_FLAGS_MAKE "${CMAKE_EXE_LINKER_FLAGS}")
+string(REPLACE "$" "$$" CMAKE_EXE_LINKER_FLAGS_MAKE_MAKE "${CMAKE_EXE_LINKER_FLAGS_MAKE}")
+configure_file(${LEAN_SOURCE_DIR}/stdlib.make.in ${CMAKE_BINARY_DIR}/stdlib.make)
 add_custom_target(make_stdlib ALL
   WORKING_DIRECTORY ${LEAN_SOURCE_DIR}
   # The actual rule is in a separate makefile because we want to prefix it with '+' to use the Make job server
   # for a parallelized nested build, but CMake doesn't let us do that.
   # We use `lean` from the previous stage, but `leanc`, headers, etc. from the current stage
-  COMMAND $(MAKE) -f ${CMAKE_BINARY_DIR}/stdlib.make Init Std Lean
+  COMMAND $(MAKE) -f ${CMAKE_BINARY_DIR}/stdlib.make Init Lean
   VERBATIM)
 
 # if we have LLVM enabled, then build `lean.h.bc` which has the LLVM bitcode
@@ -552,33 +533,17 @@ endif()
 # We declare these as separate custom targets so they use separate `make` invocations, which makes `make` recompute which dependencies
 # (e.g. `libLean.a`) are now newer than the target file
 
-if(${CMAKE_SYSTEM_NAME} MATCHES "Emscripten")
-  # dummy targets, see `MAIN_MODULE` discussion above
-  add_custom_target(Init_shared ALL
-    DEPENDS make_stdlib leanrt_initial-exec
-    COMMAND touch ${CMAKE_LIBRARY_OUTPUT_DIRECTORY}/libInit_shared${CMAKE_SHARED_LIBRARY_SUFFIX}
-  )
-  add_custom_target(leanshared ALL
-    DEPENDS Init_shared leancpp
-    COMMAND touch ${CMAKE_LIBRARY_OUTPUT_DIRECTORY}/libleanshared${CMAKE_SHARED_LIBRARY_SUFFIX}
-  )
-else()
-  add_custom_target(Init_shared ALL
-    WORKING_DIRECTORY ${LEAN_SOURCE_DIR}
-    DEPENDS make_stdlib leanrt_initial-exec
-    COMMAND $(MAKE) -f ${CMAKE_BINARY_DIR}/stdlib.make Init_shared
-    VERBATIM)
+add_custom_target(leanshared ALL
+  WORKING_DIRECTORY ${LEAN_SOURCE_DIR}
+  DEPENDS make_stdlib leancpp leanrt_initial-exec
+  COMMAND $(MAKE) -f ${CMAKE_BINARY_DIR}/stdlib.make leanshared
+  VERBATIM)
 
-  add_custom_target(leanshared ALL
-    WORKING_DIRECTORY ${LEAN_SOURCE_DIR}
-    DEPENDS Init_shared leancpp
-    COMMAND $(MAKE) -f ${CMAKE_BINARY_DIR}/stdlib.make leanshared
-    VERBATIM)
+if(${STAGE} GREATER 0)
+  if(NOT EXISTS ${LEAN_SOURCE_DIR}/lake/Lake.lean)
+    message(FATAL_ERROR "src/lake does not exist. Please check out the Lake submodule using `git submodule update --init src/lake`.")
+  endif()
 
-  string(APPEND CMAKE_EXE_LINKER_FLAGS " -lInit_shared -lleanshared")
-endif()
-
-if(NOT ${CMAKE_SYSTEM_NAME} MATCHES "Emscripten")
   add_custom_target(lake ALL
     WORKING_DIRECTORY ${LEAN_SOURCE_DIR}
     DEPENDS leanshared
@@ -588,18 +553,14 @@ endif()
 
 if(PREV_STAGE)
   add_custom_target(update-stage0
-    COMMAND bash -c 'CSRCS=${CMAKE_BINARY_DIR}/lib/temp script/lib/update-stage0'
+    COMMAND bash -c 'CSRCS=${CMAKE_BINARY_DIR}/lib/temp script/update-stage0'
     DEPENDS make_stdlib
     WORKING_DIRECTORY "${LEAN_SOURCE_DIR}/..")
-
-  add_custom_target(update-stage0-commit
-    COMMAND git commit -m "chore: update stage0"
-    DEPENDS update-stage0)
 endif()
 
 # use Bash version for building, use Lean version in bin/ for tests & distribution
 configure_file("${LEAN_SOURCE_DIR}/bin/leanc.in" "${CMAKE_BINARY_DIR}/leanc.sh" @ONLY)
-if(${STAGE} GREATER 0 AND EXISTS ${LEAN_SOURCE_DIR}/Leanc.lean AND NOT ${CMAKE_SYSTEM_NAME} MATCHES "Emscripten")
+if(${STAGE} GREATER 0 AND EXISTS ${LEAN_SOURCE_DIR}/Leanc.lean)
   configure_file("${LEAN_SOURCE_DIR}/Leanc.lean" "${CMAKE_BINARY_DIR}/leanc/Leanc.lean" @ONLY)
   add_custom_target(leanc ALL
     WORKING_DIRECTORY ${CMAKE_BINARY_DIR}/leanc
@@ -650,14 +611,3 @@ if(LEAN_INSTALL_PREFIX)
   set(LEAN_INSTALL_SUFFIX "-${LOWER_SYSTEM_NAME}" CACHE STRING "If LEAN_INSTALL_PREFIX is set, append this value to CMAKE_INSTALL_PREFIX")
   set(CMAKE_INSTALL_PREFIX "${LEAN_INSTALL_PREFIX}/lean-${LEAN_VERSION_STRING}${LEAN_INSTALL_SUFFIX}")
 endif()
-
-# Escape for `make`. Yes, twice.
-string(REPLACE "$" "$$" CMAKE_EXE_LINKER_FLAGS_MAKE "${CMAKE_EXE_LINKER_FLAGS}")
-string(REPLACE "$" "$$" CMAKE_EXE_LINKER_FLAGS_MAKE_MAKE "${CMAKE_EXE_LINKER_FLAGS_MAKE}")
-configure_file(${LEAN_SOURCE_DIR}/stdlib.make.in ${CMAKE_BINARY_DIR}/stdlib.make)
-
-if(USE_LAKE AND STAGE EQUAL 1)
-  configure_file(${LEAN_SOURCE_DIR}/lakefile.toml.in ${LEAN_SOURCE_DIR}/lakefile.toml)
-  configure_file(${LEAN_SOURCE_DIR}/lakefile.toml.in ${LEAN_SOURCE_DIR}/../tests/lakefile.toml)
-  configure_file(${LEAN_SOURCE_DIR}/lakefile.toml.in ${LEAN_SOURCE_DIR}/../lakefile.toml)
-endif()

src/Init.lean

@@ -7,9 +7,6 @@ prelude
 import Init.Prelude
 import Init.Notation
 import Init.Tactics
-import Init.TacticsExtra
-import Init.ByCases
-import Init.RCases
 import Init.Core
 import Init.Control
 import Init.Data.Basic
@@ -24,14 +21,6 @@ import Init.MetaTypes
 import Init.Meta
 import Init.NotationExtra
 import Init.SimpLemmas
-import Init.PropLemmas
 import Init.Hints
 import Init.Conv
-import Init.Guard
-import Init.Simproc
 import Init.SizeOfLemmas
-import Init.BinderPredicates
-import Init.Ext
-import Init.Omega
-import Init.MacroTrace
-import Init.Grind

src/Init/BinderPredicates.lean

@@ -1,82 +0,0 @@
-/-
-Copyright (c) 2021 Microsoft Corporation. All rights reserved.
-Released under Apache 2.0 license as described in the file LICENSE.
-Authors: Gabriel Ebner
--/
-prelude
-import Init.NotationExtra
-
-namespace Lean
-
-/--
-The syntax category of binder predicates contains predicates like `> 0`, `∈ s`, etc.
-(`: t` should not be a binder predicate because it would clash with the built-in syntax for ∀/∃.)
--/
-declare_syntax_cat binderPred
-
-/--
-`satisfies_binder_pred% t pred` expands to a proposition expressing that `t` satisfies `pred`.
--/
-syntax "satisfies_binder_pred% " term:max binderPred : term
-
--- Extend ∀ and ∃ to binder predicates.
-
-/--
-The notation `∃ x < 2, p x` is shorthand for `∃ x, x < 2 ∧ p x`,
-and similarly for other binary operators.
--/
-syntax "∃ " binderIdent binderPred ", " term : term
-/--
-The notation `∀ x < 2, p x` is shorthand for `∀ x, x < 2 → p x`,
-and similarly for other binary operators.
--/
-syntax "∀ " binderIdent binderPred ", " term : term
-
-macro_rules
-  | `(∃ $x:ident $pred:binderPred, $p) =>
-    `(∃ $x:ident, satisfies_binder_pred% $x $pred ∧ $p)
-  | `(∃ _ $pred:binderPred, $p) =>
-    `(∃ x, satisfies_binder_pred% x $pred ∧ $p)
-
-macro_rules
-  | `(∀ $x:ident $pred:binderPred, $p) =>
-    `(∀ $x:ident, satisfies_binder_pred% $x $pred → $p)
-  | `(∀ _ $pred:binderPred, $p) =>
-    `(∀ x, satisfies_binder_pred% x $pred → $p)
-
-/-- Declare `∃ x > y, ...` as syntax for `∃ x, x > y ∧ ...` -/
-binder_predicate x " > " y:term => `($x > $y)
-/-- Declare `∃ x ≥ y, ...` as syntax for `∃ x, x ≥ y ∧ ...` -/
-binder_predicate x " ≥ " y:term => `($x ≥ $y)
-/-- Declare `∃ x < y, ...` as syntax for `∃ x, x < y ∧ ...` -/
-binder_predicate x " < " y:term => `($x < $y)
-/-- Declare `∃ x ≤ y, ...` as syntax for `∃ x, x ≤ y ∧ ...` -/
-binder_predicate x " ≤ " y:term => `($x ≤ $y)
-/-- Declare `∃ x ≠ y, ...` as syntax for `∃ x, x ≠ y ∧ ...` -/
-binder_predicate x " ≠ " y:term => `($x ≠ $y)
-
-/-- Declare `∀ x ∈ y, ...` as syntax for `∀ x, x ∈ y → ...` and `∃ x ∈ y, ...` as syntax for
-`∃ x, x ∈ y ∧ ...` -/
-binder_predicate x " ∈ " y:term => `($x ∈ $y)
-
-/-- Declare `∀ x ∉ y, ...` as syntax for `∀ x, x ∉ y → ...` and `∃ x ∉ y, ...` as syntax for
-`∃ x, x ∉ y ∧ ...` -/
-binder_predicate x " ∉ " y:term => `($x ∉ $y)
-
-/-- Declare `∀ x ⊆ y, ...` as syntax for `∀ x, x ⊆ y → ...` and `∃ x ⊆ y, ...` as syntax for
-`∃ x, x ⊆ y ∧ ...` -/
-binder_predicate x " ⊆ " y:term => `($x ⊆ $y)
-
-/-- Declare `∀ x ⊂ y, ...` as syntax for `∀ x, x ⊂ y → ...` and `∃ x ⊂ y, ...` as syntax for
-`∃ x, x ⊂ y ∧ ...` -/
-binder_predicate x " ⊂ " y:term => `($x ⊂ $y)
-
-/-- Declare `∀ x ⊇ y, ...` as syntax for `∀ x, x ⊇ y → ...` and `∃ x ⊇ y, ...` as syntax for
-`∃ x, x ⊇ y ∧ ...` -/
-binder_predicate x " ⊇ " y:term => `($x ⊇ $y)
-
-/-- Declare `∀ x ⊃ y, ...` as syntax for `∀ x, x ⊃ y → ...` and `∃ x ⊃ y, ...` as syntax for
-`∃ x, x ⊃ y ∧ ...` -/
-binder_predicate x " ⊃ " y:term => `($x ⊃ $y)
-
-end Lean

src/Init/ByCases.lean

@@ -1,78 +0,0 @@
-/-
-Copyright (c) 2024 Lean FRO, LLC. All rights reserved.
-Released under Apache 2.0 license as described in the file LICENSE.
-Authors: Leonardo de Moura, Mario Carneiro
--/
-prelude
-import Init.Classical
-
-/-! # by_cases tactic and if-then-else support -/
-
-/--
-`by_cases (h :)? p` splits the main goal into two cases, assuming `h : p` in the first branch, and `h : ¬ p` in the second branch.
--/
-syntax "by_cases " (atomic(ident " : "))? term : tactic
-
-macro_rules
-  | `(tactic| by_cases $e) => `(tactic| by_cases h : $e)
-macro_rules
-  | `(tactic| by_cases $h : $e) =>
-    `(tactic| open Classical in refine if $h:ident : $e then ?pos else ?neg)
-
-/-! ## if-then-else -/
-
-@[simp] theorem if_true {_ : Decidable True} (t e : α) : ite True t e = t := if_pos trivial
-
-@[simp] theorem if_false {_ : Decidable False} (t e : α) : ite False t e = e := if_neg id
-
-theorem ite_id [Decidable c] {α} (t : α) : (if c then t else t) = t := by split <;> rfl
-
-/-- A function applied to a `dite` is a `dite` of that function applied to each of the branches. -/
-theorem apply_dite (f : α → β) (P : Prop) [Decidable P] (x : P → α) (y : ¬P → α) :
-    f (dite P x y) = dite P (fun h => f (x h)) (fun h => f (y h)) := by
-  by_cases h : P <;> simp [h]
-
-/-- A function applied to a `ite` is a `ite` of that function applied to each of the branches. -/
-theorem apply_ite (f : α → β) (P : Prop) [Decidable P] (x y : α) :
-    f (ite P x y) = ite P (f x) (f y) :=
-  apply_dite f P (fun _ => x) (fun _ => y)
-
-@[simp] theorem dite_eq_left_iff {P : Prop} [Decidable P] {B : ¬ P → α} :
-    dite P (fun _ => a) B = a ↔ ∀ h, B h = a := by
-  by_cases P <;> simp [*, forall_prop_of_true, forall_prop_of_false]
-
-@[simp] theorem dite_eq_right_iff {P : Prop} [Decidable P] {A : P → α} :
-    (dite P A fun _ => b) = b ↔ ∀ h, A h = b := by
-  by_cases P <;> simp [*, forall_prop_of_true, forall_prop_of_false]
-
-@[simp] theorem ite_eq_left_iff {P : Prop} [Decidable P] : ite P a b = a ↔ ¬P → b = a :=
-  dite_eq_left_iff
-
-@[simp] theorem ite_eq_right_iff {P : Prop} [Decidable P] : ite P a b = b ↔ P → a = b :=
-  dite_eq_right_iff
-
-/-- A `dite` whose results do not actually depend on the condition may be reduced to an `ite`. -/
-@[simp] theorem dite_eq_ite [Decidable P] : (dite P (fun _ => a) fun _ => b) = ite P a b := rfl
-
--- We don't mark this as `simp` as it is already handled by `ite_eq_right_iff`.
-theorem ite_some_none_eq_none [Decidable P] :
-    (if P then some x else none) = none ↔ ¬ P := by
-  simp only [ite_eq_right_iff]
-  rfl
-
-@[simp] theorem ite_some_none_eq_some [Decidable P] :
-    (if P then some x else none) = some y ↔ P ∧ x = y := by
-  split <;> simp_all
-
--- This is not marked as `simp` as it is already handled by `dite_eq_right_iff`.
-theorem dite_some_none_eq_none [Decidable P] {x : P → α} :
-    (if h : P then some (x h) else none) = none ↔ ¬P := by
-  simp only [dite_eq_right_iff]
-  rfl
-
-@[simp] theorem dite_some_none_eq_some [Decidable P] {x : P → α} {y : α} :
-    (if h : P then some (x h) else none) = some y ↔ ∃ h : P, x h = y := by
-  by_cases h : P <;> simp only [h, dite_cond_eq_true, dite_cond_eq_false, Option.some.injEq,
-    false_iff, not_exists]
-  case pos => exact ⟨fun h_eq ↦ Exists.intro h h_eq, fun h_exists => h_exists.2⟩
-  case neg => exact fun h_false _ ↦ h_false

src/Init/Classical.lean

@@ -1,10 +1,11 @@
 /-
 Copyright (c) 2020 Microsoft Corporation. All rights reserved.
 Released under Apache 2.0 license as described in the file LICENSE.
-Authors: Leonardo de Moura, Mario Carneiro
+Authors: Leonardo de Moura
 -/
 prelude
-import Init.PropLemmas
+import Init.Core
+import Init.NotationExtra
 
 universe u v
 
@@ -15,20 +16,13 @@ namespace Classical
 noncomputable def indefiniteDescription {α : Sort u} (p : α → Prop) (h : ∃ x, p x) : {x // p x} :=
   choice <| let ⟨x, px⟩ := h; ⟨⟨x, px⟩⟩
 
-/--
-Given that there exists an element satisfying `p`, returns one such element.
-
-This is a straightforward consequence of, and equivalent to, `Classical.choice`.
-
-See also `choose_spec`, which asserts that the returned value has property `p`.
--/
 noncomputable def choose {α : Sort u} {p : α → Prop} (h : ∃ x, p x) : α :=
   (indefiniteDescription p h).val
 
 theorem choose_spec {α : Sort u} {p : α → Prop} (h : ∃ x, p x) : p (choose h) :=
   (indefiniteDescription p h).property
 
-/-- **Diaconescu's theorem**: excluded middle from choice, Function extensionality and propositional extensionality. -/
+/-- Diaconescu's theorem: excluded middle from choice, Function extensionality and propositional extensionality. -/
 theorem em (p : Prop) : p ∨ ¬p :=
   let U (x : Prop) : Prop := x = True ∨ p
   let V (x : Prop) : Prop := x = False ∨ p
@@ -118,8 +112,8 @@ theorem skolem {α : Sort u} {b : α → Sort v} {p : ∀ x, b x → Prop} : (
 
 theorem propComplete (a : Prop) : a = True ∨ a = False :=
   match em a with
-  | Or.inl ha => Or.inl (eq_true ha)
-  | Or.inr hn => Or.inr (eq_false hn)
+  | Or.inl ha => Or.inl (propext (Iff.intro (fun _ => ⟨⟩) (fun _ => ha)))
+  | Or.inr hn => Or.inr (propext (Iff.intro (fun h => hn h) (fun h => False.elim h)))
 
 -- this supercedes byCases in Decidable
 theorem byCases {p q : Prop} (hpq : p → q) (hnpq : ¬p → q) : q :=
@@ -129,49 +123,21 @@ theorem byCases {p q : Prop} (hpq : p → q) (hnpq : ¬p → q) : q :=
 theorem byContradiction {p : Prop} (h : ¬p → False) : p :=
   Decidable.byContradiction (dec := propDecidable _) h
 
-/-- The Double Negation Theorem: `¬¬P` is equivalent to `P`.
-The left-to-right direction, double negation elimination (DNE),
-is classically true but not constructively. -/
-@[simp] theorem not_not : ¬¬a ↔ a := Decidable.not_not
+/--
+`by_cases (h :)? p` splits the main goal into two cases, assuming `h : p` in the first branch, and `h : ¬ p` in the second branch.
+-/
+syntax "by_cases " (atomic(ident " : "))? term : tactic
 
-@[simp low] theorem not_forall {p : α → Prop} : (¬∀ x, p x) ↔ ∃ x, ¬p x := Decidable.not_forall
-
-theorem not_forall_not {p : α → Prop} : (¬∀ x, ¬p x) ↔ ∃ x, p x := Decidable.not_forall_not
-theorem not_exists_not {p : α → Prop} : (¬∃ x, ¬p x) ↔ ∀ x, p x := Decidable.not_exists_not
-
-theorem forall_or_exists_not (P : α → Prop) : (∀ a, P a) ∨ ∃ a, ¬ P a := by
-  rw [← not_forall]; exact em _
-theorem exists_or_forall_not (P : α → Prop) : (∃ a, P a) ∨ ∀ a, ¬ P a := by
-  rw [← not_exists]; exact em _
-
-theorem or_iff_not_imp_left  : a ∨ b ↔ (¬a → b) := Decidable.or_iff_not_imp_left
-theorem or_iff_not_imp_right : a ∨ b ↔ (¬b → a) := Decidable.or_iff_not_imp_right
-
-theorem not_imp_iff_and_not : ¬(a → b) ↔ a ∧ ¬b := Decidable.not_imp_iff_and_not
-
-theorem not_and_iff_or_not_not : ¬(a ∧ b) ↔ ¬a ∨ ¬b := Decidable.not_and_iff_or_not_not
-
-theorem not_iff : ¬(a ↔ b) ↔ (¬a ↔ b) := Decidable.not_iff
-
-@[simp] theorem imp_iff_left_iff  : (b ↔ a → b) ↔ a ∨ b := Decidable.imp_iff_left_iff
-@[simp] theorem imp_iff_right_iff : (a → b ↔ b) ↔ a ∨ b := Decidable.imp_iff_right_iff
-
-@[simp] theorem and_or_imp : a ∧ b ∨ (a → c) ↔ a → b ∨ c := Decidable.and_or_imp
-
-@[simp] theorem not_imp : ¬(a → b) ↔ a ∧ ¬b := Decidable.not_imp_iff_and_not
-
-@[simp] theorem imp_and_neg_imp_iff (p q : Prop) : (p → q) ∧ (¬p → q) ↔ q :=
-  Iff.intro (fun (a : _ ∧ _) => (Classical.em p).rec a.left a.right)
-            (fun a => And.intro (fun _ => a) (fun _ => a))
+macro_rules
+  | `(tactic| by_cases $h : $e) =>
+    `(tactic|
+      cases em $e with
+      | inl $h => _
+      | inr $h => _)
+  | `(tactic| by_cases $e) =>
+    `(tactic|
+      cases em $e with
+      | inl h => _
+      | inr h => _)
 
 end Classical
-
-/- Export for Mathlib compat. -/
-export Classical (imp_iff_right_iff imp_and_neg_imp_iff and_or_imp not_imp)
-
-/-- Extract an element from a existential statement, using `Classical.choose`. -/
--- This enables projection notation.
-@[reducible] noncomputable def Exists.choose {p : α → Prop} (P : ∃ a, p a) : α := Classical.choose P
-
-/-- Show that an element extracted from `P : ∃ a, p a` using `P.choose` satisfies `p`. -/
-theorem Exists.choose_spec {p : α → Prop} (P : ∃ a, p a) : p P.choose := Classical.choose_spec P

src/Init/Coe.lean

@@ -290,12 +290,6 @@ between e.g. `↑x + ↑y` and `↑(x + y)`.
 -/
 syntax:1024 (name := coeNotation) "↑" term:1024 : term
 
-/-- `⇑ t` coerces `t` to a function. -/
-syntax:1024 (name := coeFunNotation) "⇑" term:1024 : term
-
-/-- `↥ t` coerces `t` to a type. -/
-syntax:1024 (name := coeSortNotation) "↥" term:1024 : term
-
 /-! # Basic instances -/
 
 instance boolToProp : Coe Bool Prop where
@@ -321,7 +315,7 @@ Helper definition used by the elaborator. It is not meant to be used directly by
 This is used for coercions between monads, in the case where we want to apply
 a monad lift and a coercion on the result type at the same time.
 -/
-@[coe_decl] abbrev Lean.Internal.liftCoeM {m : Type u → Type v} {n : Type u → Type w} {α β : Type u}
+@[inline, coe_decl] def Lean.Internal.liftCoeM {m : Type u → Type v} {n : Type u → Type w} {α β : Type u}
     [MonadLiftT m n] [∀ a, CoeT α a β] [Monad n] (x : m α) : n β := do
   let a ← liftM x
   pure (CoeT.coe a)
@@ -331,7 +325,7 @@ Helper definition used by the elaborator. It is not meant to be used directly by
 
 This is used for coercing the result type under a monad.
 -/
-@[coe_decl] abbrev Lean.Internal.coeM {m : Type u → Type v} {α β : Type u}
+@[inline, coe_decl] def Lean.Internal.coeM {m : Type u → Type v} {α β : Type u}
     [∀ a, CoeT α a β] [Monad m] (x : m α) : m β := do
   let a ← x
   pure (CoeT.coe a)

src/Init/Control/Basic.lean

@@ -20,29 +20,8 @@ def Functor.discard {f : Type u → Type v} {α : Type u} [Functor f] (x : f α)
 
 export Functor (discard)
 
-/--
-An `Alternative` functor is an `Applicative` functor that can "fail" or be "empty"
-and a binary operation `<|>` that “collects values” or finds the “left-most success”.
-
-Important instances include
-* `Option`, where `failure := none` and `<|>` returns the left-most `some`.
-* Parser combinators typically provide an `Applicative` instance for error-handling and
-  backtracking.
-  
-Error recovery and state can interact subtly. For example, the implementation of `Alternative` for `OptionT (StateT σ Id)` keeps modifications made to the state while recovering from failure, while `StateT σ (OptionT Id)` discards them.
--/
--- NB: List instance is in mathlib. Once upstreamed, add
--- * `List`, where `failure` is the empty list and `<|>` concatenates.
 class Alternative (f : Type u → Type v) extends Applicative f : Type (max (u+1) v) where
-  /--
-  Produces an empty collection or recoverable failure.  The `<|>` operator collects values or recovers
-  from failures. See `Alternative` for more details.
-  -/
   failure : {α : Type u} → f α
-  /--
-  Depending on the `Alternative` instance, collects values or recovers from `failure`s by
-  returning the leftmost success. Can be written using the `<|>` operator syntax.
-  -/
   orElse  : {α : Type u} → f α → (Unit → f α) → f α
 
 instance (f : Type u → Type v) (α : Type u) [Alternative f] : OrElse (f α) := ⟨Alternative.orElse⟩
@@ -51,15 +30,9 @@ variable {f : Type u → Type v} [Alternative f] {α : Type u}
 
 export Alternative (failure)
 
-/--
-If the proposition `p` is true, does nothing, else fails (using `failure`).
--/
 @[always_inline, inline] def guard {f : Type → Type v} [Alternative f] (p : Prop) [Decidable p] : f Unit :=
   if p then pure () else failure
 
-/--
-Returns `some x` if `f` succeeds with value `x`, else returns `none`.
--/
 @[always_inline, inline] def optional (x : f α) : f (Option α) :=
   some <$> x <|> pure none
 

src/Init/Control/Except.lean

@@ -131,7 +131,7 @@ protected def adapt {ε' α : Type u} (f : ε → ε') : ExceptT ε m α → Exc
 end ExceptT
 
 @[always_inline]
-instance (m : Type u → Type v) (ε₁ : Type u) (ε₂ : Type u) [MonadExceptOf ε₁ m] : MonadExceptOf ε₁ (ExceptT ε₂ m) where
+instance (m : Type u → Type v) (ε₁ : Type u) (ε₂ : Type u) [Monad m] [MonadExceptOf ε₁ m] : MonadExceptOf ε₁ (ExceptT ε₂ m) where
   throw e := ExceptT.mk <| throwThe ε₁ e
   tryCatch x handle := ExceptT.mk <| tryCatchThe ε₁ x handle
 

src/Init/Control/ExceptCps.lean

@@ -4,7 +4,7 @@ Released under Apache 2.0 license as described in the file LICENSE.
 Authors: Leonardo de Moura
 -/
 prelude
-import Init.Control.Lawful.Basic
+import Init.Control.Lawful
 
 /-!
 The Exception monad transformer using CPS style.
@@ -18,7 +18,6 @@ namespace ExceptCpsT
 def run {ε α : Type u} [Monad m] (x : ExceptCpsT ε m α) : m (Except ε α) :=
   x _ (fun a => pure (Except.ok a)) (fun e => pure (Except.error e))
 
-set_option linter.unusedVariables false in  -- `s` unused
 @[always_inline, inline]
 def runK {ε α : Type u} (x : ExceptCpsT ε m α) (s : ε) (ok : α → m β) (error : ε → m β) : m β :=
   x _ ok error

src/Init/Control/Lawful.lean

@@ -1,8 +1,309 @@
 /-
 Copyright (c) 2021 Microsoft Corporation. All rights reserved.
 Released under Apache 2.0 license as described in the file LICENSE.
-Authors: Sebastian Ullrich, Leonardo de Moura, Mario Carneiro
+Authors: Sebastian Ullrich, Leonardo de Moura
 -/
 prelude
-import Init.Control.Lawful.Basic
-import Init.Control.Lawful.Instances
+import Init.SimpLemmas
+import Init.Control.Except
+import Init.Control.StateRef
+
+open Function
+
+@[simp] theorem monadLift_self [Monad m] (x : m α) : monadLift x = x :=
+  rfl
+
+class LawfulFunctor (f : Type u → Type v) [Functor f] : Prop where
+  map_const          : (Functor.mapConst : α → f β → f α) = Functor.map ∘ const β
+  id_map   (x : f α) : id <$> x = x
+  comp_map (g : α → β) (h : β → γ) (x : f α) : (h ∘ g) <$> x = h <$> g <$> x
+
+export LawfulFunctor (map_const id_map comp_map)
+
+attribute [simp] id_map
+
+@[simp] theorem id_map' [Functor m] [LawfulFunctor m] (x : m α) : (fun a => a) <$> x = x :=
+  id_map x
+
+class LawfulApplicative (f : Type u → Type v) [Applicative f] extends LawfulFunctor f : Prop where
+  seqLeft_eq  (x : f α) (y : f β)     : x <* y = const β <$> x <*> y
+  seqRight_eq (x : f α) (y : f β)     : x *> y = const α id <$> x <*> y
+  pure_seq    (g : α → β) (x : f α)   : pure g <*> x = g <$> x
+  map_pure    (g : α → β) (x : α)     : g <$> (pure x : f α) = pure (g x)
+  seq_pure    {α β : Type u} (g : f (α → β)) (x : α) : g <*> pure x = (fun h => h x) <$> g
+  seq_assoc   {α β γ : Type u} (x : f α) (g : f (α → β)) (h : f (β → γ)) : h <*> (g <*> x) = ((@comp α β γ) <$> h) <*> g <*> x
+  comp_map g h x := (by
+    repeat rw [← pure_seq]
+    simp [seq_assoc, map_pure, seq_pure])
+
+export LawfulApplicative (seqLeft_eq seqRight_eq pure_seq map_pure seq_pure seq_assoc)
+
+attribute [simp] map_pure seq_pure
+
+@[simp] theorem pure_id_seq [Applicative f] [LawfulApplicative f] (x : f α) : pure id <*> x = x := by
+  simp [pure_seq]
+
+class LawfulMonad (m : Type u → Type v) [Monad m] extends LawfulApplicative m : Prop where
+  bind_pure_comp (f : α → β) (x : m α) : x >>= (fun a => pure (f a)) = f <$> x
+  bind_map       {α β : Type u} (f : m (α → β)) (x : m α) : f >>= (. <$> x) = f <*> x
+  pure_bind      (x : α) (f : α → m β) : pure x >>= f = f x
+  bind_assoc     (x : m α) (f : α → m β) (g : β → m γ) : x >>= f >>= g = x >>= fun x => f x >>= g
+  map_pure g x    := (by rw [← bind_pure_comp, pure_bind])
+  seq_pure g x    := (by rw [← bind_map]; simp [map_pure, bind_pure_comp])
+  seq_assoc x g h := (by simp [← bind_pure_comp, ← bind_map, bind_assoc, pure_bind])
+
+export LawfulMonad (bind_pure_comp bind_map pure_bind bind_assoc)
+attribute [simp] pure_bind bind_assoc
+
+@[simp] theorem bind_pure [Monad m] [LawfulMonad m] (x : m α) : x >>= pure = x := by
+  show x >>= (fun a => pure (id a)) = x
+  rw [bind_pure_comp, id_map]
+
+theorem map_eq_pure_bind [Monad m] [LawfulMonad m] (f : α → β) (x : m α) : f <$> x = x >>= fun a => pure (f a) := by
+  rw [← bind_pure_comp]
+
+theorem seq_eq_bind_map {α β : Type u} [Monad m] [LawfulMonad m] (f : m (α → β)) (x : m α) : f <*> x = f >>= (. <$> x) := by
+  rw [← bind_map]
+
+theorem bind_congr [Bind m] {x : m α} {f g : α → m β} (h : ∀ a, f a = g a) : x >>= f = x >>= g := by
+  simp [funext h]
+
+@[simp] theorem bind_pure_unit [Monad m] [LawfulMonad m] {x : m PUnit} : (x >>= fun _ => pure ⟨⟩) = x := by
+  rw [bind_pure]
+
+theorem map_congr [Functor m] {x : m α} {f g : α → β} (h : ∀ a, f a = g a) : (f <$> x : m β) = g <$> x := by
+  simp [funext h]
+
+theorem seq_eq_bind {α β : Type u} [Monad m] [LawfulMonad m] (mf : m (α → β)) (x : m α) : mf <*> x = mf >>= fun f => f <$> x := by
+  rw [bind_map]
+
+theorem seqRight_eq_bind [Monad m] [LawfulMonad m] (x : m α) (y : m β) : x *> y = x >>= fun _ => y := by
+  rw [seqRight_eq]
+  simp [map_eq_pure_bind, seq_eq_bind_map, const]
+
+theorem seqLeft_eq_bind [Monad m] [LawfulMonad m] (x : m α) (y : m β) : x <* y = x >>= fun a => y >>= fun _ => pure a := by
+  rw [seqLeft_eq]; simp [map_eq_pure_bind, seq_eq_bind_map]
+
+/-! # Id -/
+
+namespace Id
+
+@[simp] theorem map_eq (x : Id α) (f : α → β) : f <$> x = f x := rfl
+@[simp] theorem bind_eq (x : Id α) (f : α → id β) : x >>= f = f x := rfl
+@[simp] theorem pure_eq (a : α) : (pure a : Id α) = a := rfl
+
+instance : LawfulMonad Id := by
+  refine' { .. } <;> intros <;> rfl
+
+end Id
+
+/-! # ExceptT -/
+
+namespace ExceptT
+
+theorem ext [Monad m] {x y : ExceptT ε m α} (h : x.run = y.run) : x = y := by
+  simp [run] at h
+  assumption
+
+@[simp] theorem run_pure [Monad m] (x : α) : run (pure x : ExceptT ε m α) = pure (Except.ok x) := rfl
+
+@[simp] theorem run_lift  [Monad.{u, v} m] (x : m α) : run (ExceptT.lift x : ExceptT ε m α) = (Except.ok <$> x : m (Except ε α)) := rfl
+
+@[simp] theorem run_throw [Monad m] : run (throw e : ExceptT ε m β) = pure (Except.error e) := rfl
+
+@[simp] theorem run_bind_lift [Monad m] [LawfulMonad m] (x : m α) (f : α → ExceptT ε m β) : run (ExceptT.lift x >>= f : ExceptT ε m β) = x >>= fun a => run (f a) := by
+  simp[ExceptT.run, ExceptT.lift, bind, ExceptT.bind, ExceptT.mk, ExceptT.bindCont, map_eq_pure_bind]
+
+@[simp] theorem bind_throw [Monad m] [LawfulMonad m] (f : α → ExceptT ε m β) : (throw e >>= f) = throw e := by
+  simp [throw, throwThe, MonadExceptOf.throw, bind, ExceptT.bind, ExceptT.bindCont, ExceptT.mk]
+
+theorem run_bind [Monad m] (x : ExceptT ε m α)
+        : run (x >>= f : ExceptT ε m β)
+          =
+          run x >>= fun
+                     | Except.ok x => run (f x)
+                     | Except.error e => pure (Except.error e) :=
+  rfl
+
+@[simp] theorem lift_pure [Monad m] [LawfulMonad m] (a : α) : ExceptT.lift (pure a) = (pure a : ExceptT ε m α) := by
+  simp [ExceptT.lift, pure, ExceptT.pure]
+
+@[simp] theorem run_map [Monad m] [LawfulMonad m] (f : α → β) (x : ExceptT ε m α)
+    : (f <$> x).run = Except.map f <$> x.run := by
+  simp [Functor.map, ExceptT.map, map_eq_pure_bind]
+  apply bind_congr
+  intro a; cases a <;> simp [Except.map]
+
+protected theorem seq_eq {α β ε : Type u} [Monad m] (mf : ExceptT ε m (α → β)) (x : ExceptT ε m α) : mf <*> x = mf >>= fun f => f <$> x :=
+  rfl
+
+protected theorem bind_pure_comp [Monad m] [LawfulMonad m] (f : α → β) (x : ExceptT ε m α) : x >>= pure ∘ f = f <$> x := by
+  intros; rfl
+
+protected theorem seqLeft_eq {α β ε : Type u} {m : Type u → Type v} [Monad m] [LawfulMonad m] (x : ExceptT ε m α) (y : ExceptT ε m β) : x <* y = const β <$> x <*> y := by
+  show (x >>= fun a => y >>= fun _ => pure a) = (const (α := α) β <$> x) >>= fun f => f <$> y
+  rw [← ExceptT.bind_pure_comp]
+  apply ext
+  simp [run_bind]
+  apply bind_congr
+  intro
+  | Except.error _ => simp
+  | Except.ok _ =>
+    simp [map_eq_pure_bind]; apply bind_congr; intro b;
+    cases b <;> simp [comp, Except.map, const]
+
+protected theorem seqRight_eq [Monad m] [LawfulMonad m] (x : ExceptT ε m α) (y : ExceptT ε m β) : x *> y = const α id <$> x <*> y := by
+  show (x >>= fun _ => y) = (const α id <$> x) >>= fun f => f <$> y
+  rw [← ExceptT.bind_pure_comp]
+  apply ext
+  simp [run_bind]
+  apply bind_congr
+  intro a; cases a <;> simp
+
+instance [Monad m] [LawfulMonad m] : LawfulMonad (ExceptT ε m) where
+  id_map         := by intros; apply ext; simp
+  map_const      := by intros; rfl
+  seqLeft_eq     := ExceptT.seqLeft_eq
+  seqRight_eq    := ExceptT.seqRight_eq
+  pure_seq       := by intros; apply ext; simp [ExceptT.seq_eq, run_bind]
+  bind_pure_comp := ExceptT.bind_pure_comp
+  bind_map       := by intros; rfl
+  pure_bind      := by intros; apply ext; simp [run_bind]
+  bind_assoc     := by intros; apply ext; simp [run_bind]; apply bind_congr; intro a; cases a <;> simp
+
+end ExceptT
+
+/-! # ReaderT -/
+
+namespace ReaderT
+
+theorem ext {x y : ReaderT ρ m α} (h : ∀ ctx, x.run ctx = y.run ctx) : x = y := by
+  simp [run] at h
+  exact funext h
+
+@[simp] theorem run_pure [Monad m] (a : α) (ctx : ρ) : (pure a : ReaderT ρ m α).run ctx = pure a := rfl
+
+@[simp] theorem run_bind [Monad m] (x : ReaderT ρ m α) (f : α → ReaderT ρ m β) (ctx : ρ)
+    : (x >>= f).run ctx = x.run ctx >>= λ a => (f a).run ctx := rfl
+
+@[simp] theorem run_mapConst [Monad m] (a : α) (x : ReaderT ρ m β) (ctx : ρ)
+    : (Functor.mapConst a x).run ctx = Functor.mapConst a (x.run ctx) := rfl
+
+@[simp] theorem run_map [Monad m] (f : α → β) (x : ReaderT ρ m α) (ctx : ρ)
+    : (f <$> x).run ctx = f <$> x.run ctx := rfl
+
+@[simp] theorem run_monadLift [MonadLiftT n m] (x : n α) (ctx : ρ)
+    : (monadLift x : ReaderT ρ m α).run ctx = (monadLift x : m α) := rfl
+
+@[simp] theorem run_monadMap [MonadFunctor n m] (f : {β : Type u} → n β → n β) (x : ReaderT ρ m α) (ctx : ρ)
+    : (monadMap @f x : ReaderT ρ m α).run ctx = monadMap @f (x.run ctx) := rfl
+
+@[simp] theorem run_read [Monad m] (ctx : ρ) : (ReaderT.read : ReaderT ρ m ρ).run ctx = pure ctx := rfl
+
+@[simp] theorem run_seq {α β : Type u} [Monad m] (f : ReaderT ρ m (α → β)) (x : ReaderT ρ m α) (ctx : ρ)
+    : (f <*> x).run ctx = (f.run ctx <*> x.run ctx) := rfl
+
+@[simp] theorem run_seqRight [Monad m] (x : ReaderT ρ m α) (y : ReaderT ρ m β) (ctx : ρ)
+    : (x *> y).run ctx = (x.run ctx *> y.run ctx) := rfl
+
+@[simp] theorem run_seqLeft [Monad m] (x : ReaderT ρ m α) (y : ReaderT ρ m β) (ctx : ρ)
+    : (x <* y).run ctx = (x.run ctx <* y.run ctx) := rfl
+
+instance [Monad m] [LawfulFunctor m] : LawfulFunctor (ReaderT ρ m) where
+  id_map    := by intros; apply ext; simp
+  map_const := by intros; funext a b; apply ext; intros; simp [map_const]
+  comp_map  := by intros; apply ext; intros; simp [comp_map]
+
+instance [Monad m] [LawfulApplicative m] : LawfulApplicative (ReaderT ρ m) where
+  seqLeft_eq  := by intros; apply ext; intros; simp [seqLeft_eq]
+  seqRight_eq := by intros; apply ext; intros; simp [seqRight_eq]
+  pure_seq    := by intros; apply ext; intros; simp [pure_seq]
+  map_pure    := by intros; apply ext; intros; simp [map_pure]
+  seq_pure    := by intros; apply ext; intros; simp [seq_pure]
+  seq_assoc   := by intros; apply ext; intros; simp [seq_assoc]
+
+instance [Monad m] [LawfulMonad m] : LawfulMonad (ReaderT ρ m) where
+  bind_pure_comp := by intros; apply ext; intros; simp [LawfulMonad.bind_pure_comp]
+  bind_map       := by intros; apply ext; intros; simp [bind_map]
+  pure_bind      := by intros; apply ext; intros; simp
+  bind_assoc     := by intros; apply ext; intros; simp
+
+end ReaderT
+
+/-! # StateRefT -/
+
+instance [Monad m] [LawfulMonad m] : LawfulMonad (StateRefT' ω σ m) :=
+  inferInstanceAs (LawfulMonad (ReaderT (ST.Ref ω σ) m))
+
+/-! # StateT -/
+
+namespace StateT
+
+theorem ext {x y : StateT σ m α} (h : ∀ s, x.run s = y.run s) : x = y :=
+  funext h
+
+@[simp] theorem run'_eq [Monad m] (x : StateT σ m α) (s : σ) : run' x s = (·.1) <$> run x s :=
+  rfl
+
+@[simp] theorem run_pure [Monad m] (a : α) (s : σ) : (pure a : StateT σ m α).run s = pure (a, s) := rfl
+
+@[simp] theorem run_bind [Monad m] (x : StateT σ m α) (f : α → StateT σ m β) (s : σ)
+    : (x >>= f).run s = x.run s >>= λ p => (f p.1).run p.2 := by
+  simp [bind, StateT.bind, run]
+
+@[simp] theorem run_map {α β σ : Type u} [Monad m] [LawfulMonad m] (f : α → β) (x : StateT σ m α) (s : σ) : (f <$> x).run s = (fun (p : α × σ) => (f p.1, p.2)) <$> x.run s := by
+  simp [Functor.map, StateT.map, run, map_eq_pure_bind]
+
+@[simp] theorem run_get [Monad m] (s : σ)    : (get : StateT σ m σ).run s = pure (s, s) := rfl
+
+@[simp] theorem run_set [Monad m] (s s' : σ) : (set s' : StateT σ m PUnit).run s = pure (⟨⟩, s') := rfl
+
+@[simp] theorem run_modify [Monad m] (f : σ → σ) (s : σ) : (modify f : StateT σ m PUnit).run s = pure (⟨⟩, f s) := rfl
+
+@[simp] theorem run_modifyGet [Monad m] (f : σ → α × σ) (s : σ) : (modifyGet f : StateT σ m α).run s = pure ((f s).1, (f s).2) := by
+  simp [modifyGet, MonadStateOf.modifyGet, StateT.modifyGet, run]
+
+@[simp] theorem run_lift {α σ : Type u} [Monad m] (x : m α) (s : σ) : (StateT.lift x : StateT σ m α).run s = x >>= fun a => pure (a, s) := rfl
+
+@[simp] theorem run_bind_lift {α σ : Type u} [Monad m] [LawfulMonad m] (x : m α) (f : α → StateT σ m β) (s : σ) : (StateT.lift x >>= f).run s = x >>= fun a => (f a).run s := by
+  simp [StateT.lift, StateT.run, bind, StateT.bind]
+
+@[simp] theorem run_monadLift {α σ : Type u} [Monad m] [MonadLiftT n m] (x : n α) (s : σ) : (monadLift x : StateT σ m α).run s = (monadLift x : m α) >>= fun a => pure (a, s) := rfl
+
+@[simp] theorem run_monadMap [Monad m] [MonadFunctor n m] (f : {β : Type u} → n β → n β) (x : StateT σ m α) (s : σ)
+    : (monadMap @f x : StateT σ m α).run s = monadMap @f (x.run s) := rfl
+
+@[simp] theorem run_seq {α β σ : Type u} [Monad m] [LawfulMonad m] (f : StateT σ m (α → β)) (x : StateT σ m α) (s : σ) : (f <*> x).run s = (f.run s >>= fun fs => (fun (p : α × σ) => (fs.1 p.1, p.2)) <$> x.run fs.2) := by
+  show (f >>= fun g => g <$> x).run s = _
+  simp
+
+@[simp] theorem run_seqRight [Monad m] [LawfulMonad m] (x : StateT σ m α) (y : StateT σ m β) (s : σ) : (x *> y).run s = (x.run s >>= fun p => y.run p.2) := by
+  show (x >>= fun _ => y).run s = _
+  simp
+
+@[simp] theorem run_seqLeft {α β σ : Type u} [Monad m] [LawfulMonad m] (x : StateT σ m α) (y : StateT σ m β) (s : σ) : (x <* y).run s = (x.run s >>= fun p => y.run p.2 >>= fun p' => pure (p.1, p'.2)) := by
+  show (x >>= fun a => y >>= fun _ => pure a).run s = _
+  simp
+
+theorem seqRight_eq [Monad m] [LawfulMonad m] (x : StateT σ m α) (y : StateT σ m β) : x *> y = const α id <$> x <*> y := by
+  apply ext; intro s
+  simp [map_eq_pure_bind, const]
+  apply bind_congr; intro p; cases p
+  simp [Prod.eta]
+
+theorem seqLeft_eq [Monad m] [LawfulMonad m] (x : StateT σ m α) (y : StateT σ m β) : x <* y = const β <$> x <*> y := by
+  apply ext; intro s
+  simp [map_eq_pure_bind]
+
+instance [Monad m] [LawfulMonad m] : LawfulMonad (StateT σ m) where
+  id_map         := by intros; apply ext; intros; simp[Prod.eta]
+  map_const      := by intros; rfl
+  seqLeft_eq     := seqLeft_eq
+  seqRight_eq    := seqRight_eq
+  pure_seq       := by intros; apply ext; intros; simp
+  bind_pure_comp := by intros; apply ext; intros; simp; apply LawfulMonad.bind_pure_comp
+  bind_map       := by intros; rfl
+  pure_bind      := by intros; apply ext; intros; simp
+  bind_assoc     := by intros; apply ext; intros; simp
+
+end StateT

src/Init/Control/Lawful/Basic.lean

@@ -1,169 +0,0 @@
-/-
-Copyright (c) 2021 Microsoft Corporation. All rights reserved.
-Released under Apache 2.0 license as described in the file LICENSE.
-Authors: Sebastian Ullrich, Leonardo de Moura, Mario Carneiro
--/
-prelude
-import Init.SimpLemmas
-import Init.Meta
-
-open Function
-
-@[simp] theorem monadLift_self {m : Type u → Type v} (x : m α) : monadLift x = x :=
-  rfl
-
-/--
-The `Functor` typeclass only contains the operations of a functor.
-`LawfulFunctor` further asserts that these operations satisfy the laws of a functor,
-including the preservation of the identity and composition laws:
-```
-id <$> x = x
-(h ∘ g) <$> x = h <$> g <$> x
-```
--/
-class LawfulFunctor (f : Type u → Type v) [Functor f] : Prop where
-  map_const          : (Functor.mapConst : α → f β → f α) = Functor.map ∘ const β
-  id_map   (x : f α) : id <$> x = x
-  comp_map (g : α → β) (h : β → γ) (x : f α) : (h ∘ g) <$> x = h <$> g <$> x
-
-export LawfulFunctor (map_const id_map comp_map)
-
-attribute [simp] id_map
-
-@[simp] theorem id_map' [Functor m] [LawfulFunctor m] (x : m α) : (fun a => a) <$> x = x :=
-  id_map x
-
-/--
-The `Applicative` typeclass only contains the operations of an applicative functor.
-`LawfulApplicative` further asserts that these operations satisfy the laws of an applicative functor:
-```
-pure id <*> v = v
-pure (·∘·) <*> u <*> v <*> w = u <*> (v <*> w)
-pure f <*> pure x = pure (f x)
-u <*> pure y = pure (· y) <*> u
-```
--/
-class LawfulApplicative (f : Type u → Type v) [Applicative f] extends LawfulFunctor f : Prop where
-  seqLeft_eq  (x : f α) (y : f β)     : x <* y = const β <$> x <*> y
-  seqRight_eq (x : f α) (y : f β)     : x *> y = const α id <$> x <*> y
-  pure_seq    (g : α → β) (x : f α)   : pure g <*> x = g <$> x
-  map_pure    (g : α → β) (x : α)     : g <$> (pure x : f α) = pure (g x)
-  seq_pure    {α β : Type u} (g : f (α → β)) (x : α) : g <*> pure x = (fun h => h x) <$> g
-  seq_assoc   {α β γ : Type u} (x : f α) (g : f (α → β)) (h : f (β → γ)) : h <*> (g <*> x) = ((@comp α β γ) <$> h) <*> g <*> x
-  comp_map g h x := (by
-    repeat rw [← pure_seq]
-    simp [seq_assoc, map_pure, seq_pure])
-
-export LawfulApplicative (seqLeft_eq seqRight_eq pure_seq map_pure seq_pure seq_assoc)
-
-attribute [simp] map_pure seq_pure
-
-@[simp] theorem pure_id_seq [Applicative f] [LawfulApplicative f] (x : f α) : pure id <*> x = x := by
-  simp [pure_seq]
-
-/--
-The `Monad` typeclass only contains the operations of a monad.
-`LawfulMonad` further asserts that these operations satisfy the laws of a monad,
-including associativity and identity laws for `bind`:
-```
-pure x >>= f = f x
-x >>= pure = x
-x >>= f >>= g = x >>= (fun x => f x >>= g)
-```
-
-`LawfulMonad.mk'` is an alternative constructor containing useful defaults for many fields.
--/
-class LawfulMonad (m : Type u → Type v) [Monad m] extends LawfulApplicative m : Prop where
-  bind_pure_comp (f : α → β) (x : m α) : x >>= (fun a => pure (f a)) = f <$> x
-  bind_map       {α β : Type u} (f : m (α → β)) (x : m α) : f >>= (. <$> x) = f <*> x
-  pure_bind      (x : α) (f : α → m β) : pure x >>= f = f x
-  bind_assoc     (x : m α) (f : α → m β) (g : β → m γ) : x >>= f >>= g = x >>= fun x => f x >>= g
-  map_pure g x    := (by rw [← bind_pure_comp, pure_bind])
-  seq_pure g x    := (by rw [← bind_map]; simp [map_pure, bind_pure_comp])
-  seq_assoc x g h := (by simp [← bind_pure_comp, ← bind_map, bind_assoc, pure_bind])
-
-export LawfulMonad (bind_pure_comp bind_map pure_bind bind_assoc)
-attribute [simp] pure_bind bind_assoc
-
-@[simp] theorem bind_pure [Monad m] [LawfulMonad m] (x : m α) : x >>= pure = x := by
-  show x >>= (fun a => pure (id a)) = x
-  rw [bind_pure_comp, id_map]
-
-theorem map_eq_pure_bind [Monad m] [LawfulMonad m] (f : α → β) (x : m α) : f <$> x = x >>= fun a => pure (f a) := by
-  rw [← bind_pure_comp]
-
-theorem seq_eq_bind_map {α β : Type u} [Monad m] [LawfulMonad m] (f : m (α → β)) (x : m α) : f <*> x = f >>= (. <$> x) := by
-  rw [← bind_map]
-
-theorem bind_congr [Bind m] {x : m α} {f g : α → m β} (h : ∀ a, f a = g a) : x >>= f = x >>= g := by
-  simp [funext h]
-
-@[simp] theorem bind_pure_unit [Monad m] [LawfulMonad m] {x : m PUnit} : (x >>= fun _ => pure ⟨⟩) = x := by
-  rw [bind_pure]
-
-theorem map_congr [Functor m] {x : m α} {f g : α → β} (h : ∀ a, f a = g a) : (f <$> x : m β) = g <$> x := by
-  simp [funext h]
-
-theorem seq_eq_bind {α β : Type u} [Monad m] [LawfulMonad m] (mf : m (α → β)) (x : m α) : mf <*> x = mf >>= fun f => f <$> x := by
-  rw [bind_map]
-
-theorem seqRight_eq_bind [Monad m] [LawfulMonad m] (x : m α) (y : m β) : x *> y = x >>= fun _ => y := by
-  rw [seqRight_eq]
-  simp [map_eq_pure_bind, seq_eq_bind_map, const]
-
-theorem seqLeft_eq_bind [Monad m] [LawfulMonad m] (x : m α) (y : m β) : x <* y = x >>= fun a => y >>= fun _ => pure a := by
-  rw [seqLeft_eq]; simp [map_eq_pure_bind, seq_eq_bind_map]
-
-/--
-An alternative constructor for `LawfulMonad` which has more
-defaultable fields in the common case.
--/
-theorem LawfulMonad.mk' (m : Type u → Type v) [Monad m]
-    (id_map : ∀ {α} (x : m α), id <$> x = x)
-    (pure_bind : ∀ {α β} (x : α) (f : α → m β), pure x >>= f = f x)
-    (bind_assoc : ∀ {α β γ} (x : m α) (f : α → m β) (g : β → m γ),
-      x >>= f >>= g = x >>= fun x => f x >>= g)
-    (map_const : ∀ {α β} (x : α) (y : m β),
-      Functor.mapConst x y = Function.const β x <$> y := by intros; rfl)
-    (seqLeft_eq : ∀ {α β} (x : m α) (y : m β),
-      x <* y = (x >>= fun a => y >>= fun _ => pure a) := by intros; rfl)
-    (seqRight_eq : ∀ {α β} (x : m α) (y : m β), x *> y = (x >>= fun _ => y) := by intros; rfl)
-    (bind_pure_comp : ∀ {α β} (f : α → β) (x : m α),
-      x >>= (fun y => pure (f y)) = f <$> x := by intros; rfl)
-    (bind_map : ∀ {α β} (f : m (α → β)) (x : m α), f >>= (. <$> x) = f <*> x := by intros; rfl)
-    : LawfulMonad m :=
-  have map_pure {α β} (g : α → β) (x : α) : g <$> (pure x : m α) = pure (g x) := by
-    rw [← bind_pure_comp]; simp [pure_bind]
-  { id_map, bind_pure_comp, bind_map, pure_bind, bind_assoc, map_pure,
-    comp_map := by simp [← bind_pure_comp, bind_assoc, pure_bind]
-    pure_seq := by intros; rw [← bind_map]; simp [pure_bind]
-    seq_pure := by intros; rw [← bind_map]; simp [map_pure, bind_pure_comp]
-    seq_assoc := by simp [← bind_pure_comp, ← bind_map, bind_assoc, pure_bind]
-    map_const := funext fun x => funext (map_const x)
-    seqLeft_eq := by simp [seqLeft_eq, ← bind_map, ← bind_pure_comp, pure_bind, bind_assoc]
-    seqRight_eq := fun x y => by
-      rw [seqRight_eq, ← bind_map, ← bind_pure_comp, bind_assoc]; simp [pure_bind, id_map] }
-
-/-! # Id -/
-
-namespace Id
-
-@[simp] theorem map_eq (x : Id α) (f : α → β) : f <$> x = f x := rfl
-@[simp] theorem bind_eq (x : Id α) (f : α → id β) : x >>= f = f x := rfl
-@[simp] theorem pure_eq (a : α) : (pure a : Id α) = a := rfl
-
-instance : LawfulMonad Id := by
-  refine' { .. } <;> intros <;> rfl
-
-end Id
-
-/-! # Option -/
-
-instance : LawfulMonad Option := LawfulMonad.mk'
-  (id_map := fun x => by cases x <;> rfl)
-  (pure_bind := fun x f => rfl)
-  (bind_assoc := fun x f g => by cases x <;> rfl)
-  (bind_pure_comp := fun f x => by cases x <;> rfl)
-
-instance : LawfulApplicative Option := inferInstance
-instance : LawfulFunctor Option := inferInstance

src/Init/Control/Lawful/Instances.lean

@@ -1,248 +0,0 @@
-/-
-Copyright (c) 2021 Microsoft Corporation. All rights reserved.
-Released under Apache 2.0 license as described in the file LICENSE.
-Authors: Sebastian Ullrich, Leonardo de Moura, Mario Carneiro
--/
-prelude
-import Init.Control.Lawful.Basic
-import Init.Control.Except
-import Init.Control.StateRef
-
-open Function
-
-/-! # ExceptT -/
-
-namespace ExceptT
-
-theorem ext {x y : ExceptT ε m α} (h : x.run = y.run) : x = y := by
-  simp [run] at h
-  assumption
-
-@[simp] theorem run_pure [Monad m] (x : α) : run (pure x : ExceptT ε m α) = pure (Except.ok x) := rfl
-
-@[simp] theorem run_lift  [Monad.{u, v} m] (x : m α) : run (ExceptT.lift x : ExceptT ε m α) = (Except.ok <$> x : m (Except ε α)) := rfl
-
-@[simp] theorem run_throw [Monad m] : run (throw e : ExceptT ε m β) = pure (Except.error e) := rfl
-
-@[simp] theorem run_bind_lift [Monad m] [LawfulMonad m] (x : m α) (f : α → ExceptT ε m β) : run (ExceptT.lift x >>= f : ExceptT ε m β) = x >>= fun a => run (f a) := by
-  simp[ExceptT.run, ExceptT.lift, bind, ExceptT.bind, ExceptT.mk, ExceptT.bindCont, map_eq_pure_bind]
-
-@[simp] theorem bind_throw [Monad m] [LawfulMonad m] (f : α → ExceptT ε m β) : (throw e >>= f) = throw e := by
-  simp [throw, throwThe, MonadExceptOf.throw, bind, ExceptT.bind, ExceptT.bindCont, ExceptT.mk]
-
-theorem run_bind [Monad m] (x : ExceptT ε m α)
-        : run (x >>= f : ExceptT ε m β)
-          =
-          run x >>= fun
-                     | Except.ok x => run (f x)
-                     | Except.error e => pure (Except.error e) :=
-  rfl
-
-@[simp] theorem lift_pure [Monad m] [LawfulMonad m] (a : α) : ExceptT.lift (pure a) = (pure a : ExceptT ε m α) := by
-  simp [ExceptT.lift, pure, ExceptT.pure]
-
-@[simp] theorem run_map [Monad m] [LawfulMonad m] (f : α → β) (x : ExceptT ε m α)
-    : (f <$> x).run = Except.map f <$> x.run := by
-  simp [Functor.map, ExceptT.map, map_eq_pure_bind]
-  apply bind_congr
-  intro a; cases a <;> simp [Except.map]
-
-protected theorem seq_eq {α β ε : Type u} [Monad m] (mf : ExceptT ε m (α → β)) (x : ExceptT ε m α) : mf <*> x = mf >>= fun f => f <$> x :=
-  rfl
-
-protected theorem bind_pure_comp [Monad m] (f : α → β) (x : ExceptT ε m α) : x >>= pure ∘ f = f <$> x := by
-  intros; rfl
-
-protected theorem seqLeft_eq {α β ε : Type u} {m : Type u → Type v} [Monad m] [LawfulMonad m] (x : ExceptT ε m α) (y : ExceptT ε m β) : x <* y = const β <$> x <*> y := by
-  show (x >>= fun a => y >>= fun _ => pure a) = (const (α := α) β <$> x) >>= fun f => f <$> y
-  rw [← ExceptT.bind_pure_comp]
-  apply ext
-  simp [run_bind]
-  apply bind_congr
-  intro
-  | Except.error _ => simp
-  | Except.ok _ =>
-    simp [map_eq_pure_bind]; apply bind_congr; intro b;
-    cases b <;> simp [comp, Except.map, const]
-
-protected theorem seqRight_eq [Monad m] [LawfulMonad m] (x : ExceptT ε m α) (y : ExceptT ε m β) : x *> y = const α id <$> x <*> y := by
-  show (x >>= fun _ => y) = (const α id <$> x) >>= fun f => f <$> y
-  rw [← ExceptT.bind_pure_comp]
-  apply ext
-  simp [run_bind]
-  apply bind_congr
-  intro a; cases a <;> simp
-
-instance [Monad m] [LawfulMonad m] : LawfulMonad (ExceptT ε m) where
-  id_map         := by intros; apply ext; simp
-  map_const      := by intros; rfl
-  seqLeft_eq     := ExceptT.seqLeft_eq
-  seqRight_eq    := ExceptT.seqRight_eq
-  pure_seq       := by intros; apply ext; simp [ExceptT.seq_eq, run_bind]
-  bind_pure_comp := ExceptT.bind_pure_comp
-  bind_map       := by intros; rfl
-  pure_bind      := by intros; apply ext; simp [run_bind]
-  bind_assoc     := by intros; apply ext; simp [run_bind]; apply bind_congr; intro a; cases a <;> simp
-
-end ExceptT
-
-/-! # Except -/
-
-instance : LawfulMonad (Except ε) := LawfulMonad.mk'
-  (id_map := fun x => by cases x <;> rfl)
-  (pure_bind := fun a f => rfl)
-  (bind_assoc := fun a f g => by cases a <;> rfl)
-
-instance : LawfulApplicative (Except ε) := inferInstance
-instance : LawfulFunctor (Except ε) := inferInstance
-
-/-! # ReaderT -/
-
-namespace ReaderT
-
-theorem ext {x y : ReaderT ρ m α} (h : ∀ ctx, x.run ctx = y.run ctx) : x = y := by
-  simp [run] at h
-  exact funext h
-
-@[simp] theorem run_pure [Monad m] (a : α) (ctx : ρ) : (pure a : ReaderT ρ m α).run ctx = pure a := rfl
-
-@[simp] theorem run_bind [Monad m] (x : ReaderT ρ m α) (f : α → ReaderT ρ m β) (ctx : ρ)
-    : (x >>= f).run ctx = x.run ctx >>= λ a => (f a).run ctx := rfl
-
-@[simp] theorem run_mapConst [Monad m] (a : α) (x : ReaderT ρ m β) (ctx : ρ)
-    : (Functor.mapConst a x).run ctx = Functor.mapConst a (x.run ctx) := rfl
-
-@[simp] theorem run_map [Monad m] (f : α → β) (x : ReaderT ρ m α) (ctx : ρ)
-    : (f <$> x).run ctx = f <$> x.run ctx := rfl
-
-@[simp] theorem run_monadLift [MonadLiftT n m] (x : n α) (ctx : ρ)
-    : (monadLift x : ReaderT ρ m α).run ctx = (monadLift x : m α) := rfl
-
-@[simp] theorem run_monadMap [MonadFunctor n m] (f : {β : Type u} → n β → n β) (x : ReaderT ρ m α) (ctx : ρ)
-    : (monadMap @f x : ReaderT ρ m α).run ctx = monadMap @f (x.run ctx) := rfl
-
-@[simp] theorem run_read [Monad m] (ctx : ρ) : (ReaderT.read : ReaderT ρ m ρ).run ctx = pure ctx := rfl
-
-@[simp] theorem run_seq {α β : Type u} [Monad m] (f : ReaderT ρ m (α → β)) (x : ReaderT ρ m α) (ctx : ρ)
-    : (f <*> x).run ctx = (f.run ctx <*> x.run ctx) := rfl
-
-@[simp] theorem run_seqRight [Monad m] (x : ReaderT ρ m α) (y : ReaderT ρ m β) (ctx : ρ)
-    : (x *> y).run ctx = (x.run ctx *> y.run ctx) := rfl
-
-@[simp] theorem run_seqLeft [Monad m] (x : ReaderT ρ m α) (y : ReaderT ρ m β) (ctx : ρ)
-    : (x <* y).run ctx = (x.run ctx <* y.run ctx) := rfl
-
-instance [Monad m] [LawfulFunctor m] : LawfulFunctor (ReaderT ρ m) where
-  id_map    := by intros; apply ext; simp
-  map_const := by intros; funext a b; apply ext; intros; simp [map_const]
-  comp_map  := by intros; apply ext; intros; simp [comp_map]
-
-instance [Monad m] [LawfulApplicative m] : LawfulApplicative (ReaderT ρ m) where
-  seqLeft_eq  := by intros; apply ext; intros; simp [seqLeft_eq]
-  seqRight_eq := by intros; apply ext; intros; simp [seqRight_eq]
-  pure_seq    := by intros; apply ext; intros; simp [pure_seq]
-  map_pure    := by intros; apply ext; intros; simp [map_pure]
-  seq_pure    := by intros; apply ext; intros; simp [seq_pure]
-  seq_assoc   := by intros; apply ext; intros; simp [seq_assoc]
-
-instance [Monad m] [LawfulMonad m] : LawfulMonad (ReaderT ρ m) where
-  bind_pure_comp := by intros; apply ext; intros; simp [LawfulMonad.bind_pure_comp]
-  bind_map       := by intros; apply ext; intros; simp [bind_map]
-  pure_bind      := by intros; apply ext; intros; simp
-  bind_assoc     := by intros; apply ext; intros; simp
-
-end ReaderT
-
-/-! # StateRefT -/
-
-instance [Monad m] [LawfulMonad m] : LawfulMonad (StateRefT' ω σ m) :=
-  inferInstanceAs (LawfulMonad (ReaderT (ST.Ref ω σ) m))
-
-/-! # StateT -/
-
-namespace StateT
-
-theorem ext {x y : StateT σ m α} (h : ∀ s, x.run s = y.run s) : x = y :=
-  funext h
-
-@[simp] theorem run'_eq [Monad m] (x : StateT σ m α) (s : σ) : run' x s = (·.1) <$> run x s :=
-  rfl
-
-@[simp] theorem run_pure [Monad m] (a : α) (s : σ) : (pure a : StateT σ m α).run s = pure (a, s) := rfl
-
-@[simp] theorem run_bind [Monad m] (x : StateT σ m α) (f : α → StateT σ m β) (s : σ)
-    : (x >>= f).run s = x.run s >>= λ p => (f p.1).run p.2 := by
-  simp [bind, StateT.bind, run]
-
-@[simp] theorem run_map {α β σ : Type u} [Monad m] [LawfulMonad m] (f : α → β) (x : StateT σ m α) (s : σ) : (f <$> x).run s = (fun (p : α × σ) => (f p.1, p.2)) <$> x.run s := by
-  simp [Functor.map, StateT.map, run, map_eq_pure_bind]
-
-@[simp] theorem run_get [Monad m] (s : σ)    : (get : StateT σ m σ).run s = pure (s, s) := rfl
-
-@[simp] theorem run_set [Monad m] (s s' : σ) : (set s' : StateT σ m PUnit).run s = pure (⟨⟩, s') := rfl
-
-@[simp] theorem run_modify [Monad m] (f : σ → σ) (s : σ) : (modify f : StateT σ m PUnit).run s = pure (⟨⟩, f s) := rfl
-
-@[simp] theorem run_modifyGet [Monad m] (f : σ → α × σ) (s : σ) : (modifyGet f : StateT σ m α).run s = pure ((f s).1, (f s).2) := by
-  simp [modifyGet, MonadStateOf.modifyGet, StateT.modifyGet, run]
-
-@[simp] theorem run_lift {α σ : Type u} [Monad m] (x : m α) (s : σ) : (StateT.lift x : StateT σ m α).run s = x >>= fun a => pure (a, s) := rfl
-
-@[simp] theorem run_bind_lift {α σ : Type u} [Monad m] [LawfulMonad m] (x : m α) (f : α → StateT σ m β) (s : σ) : (StateT.lift x >>= f).run s = x >>= fun a => (f a).run s := by
-  simp [StateT.lift, StateT.run, bind, StateT.bind]
-
-@[simp] theorem run_monadLift {α σ : Type u} [Monad m] [MonadLiftT n m] (x : n α) (s : σ) : (monadLift x : StateT σ m α).run s = (monadLift x : m α) >>= fun a => pure (a, s) := rfl
-
-@[simp] theorem run_monadMap [Monad m] [MonadFunctor n m] (f : {β : Type u} → n β → n β) (x : StateT σ m α) (s : σ)
-    : (monadMap @f x : StateT σ m α).run s = monadMap @f (x.run s) := rfl
-
-@[simp] theorem run_seq {α β σ : Type u} [Monad m] [LawfulMonad m] (f : StateT σ m (α → β)) (x : StateT σ m α) (s : σ) : (f <*> x).run s = (f.run s >>= fun fs => (fun (p : α × σ) => (fs.1 p.1, p.2)) <$> x.run fs.2) := by
-  show (f >>= fun g => g <$> x).run s = _
-  simp
-
-@[simp] theorem run_seqRight [Monad m] (x : StateT σ m α) (y : StateT σ m β) (s : σ) : (x *> y).run s = (x.run s >>= fun p => y.run p.2) := by
-  show (x >>= fun _ => y).run s = _
-  simp
-
-@[simp] theorem run_seqLeft {α β σ : Type u} [Monad m] (x : StateT σ m α) (y : StateT σ m β) (s : σ) : (x <* y).run s = (x.run s >>= fun p => y.run p.2 >>= fun p' => pure (p.1, p'.2)) := by
-  show (x >>= fun a => y >>= fun _ => pure a).run s = _
-  simp
-
-theorem seqRight_eq [Monad m] [LawfulMonad m] (x : StateT σ m α) (y : StateT σ m β) : x *> y = const α id <$> x <*> y := by
-  apply ext; intro s
-  simp [map_eq_pure_bind, const]
-  apply bind_congr; intro p; cases p
-  simp [Prod.eta]
-
-theorem seqLeft_eq [Monad m] [LawfulMonad m] (x : StateT σ m α) (y : StateT σ m β) : x <* y = const β <$> x <*> y := by
-  apply ext; intro s
-  simp [map_eq_pure_bind]
-
-instance [Monad m] [LawfulMonad m] : LawfulMonad (StateT σ m) where
-  id_map         := by intros; apply ext; intros; simp[Prod.eta]
-  map_const      := by intros; rfl
-  seqLeft_eq     := seqLeft_eq
-  seqRight_eq    := seqRight_eq
-  pure_seq       := by intros; apply ext; intros; simp
-  bind_pure_comp := by intros; apply ext; intros; simp; apply LawfulMonad.bind_pure_comp
-  bind_map       := by intros; rfl
-  pure_bind      := by intros; apply ext; intros; simp
-  bind_assoc     := by intros; apply ext; intros; simp
-
-end StateT
-
-/-! # EStateM -/
-
-instance : LawfulMonad (EStateM ε σ) := .mk'
-  (id_map := fun x => funext <| fun s => by
-    dsimp only [EStateM.instMonad, EStateM.map]
-    match x s with
-    | .ok _ _ => rfl
-    | .error _ _ => rfl)
-  (pure_bind := fun _ _ => rfl)
-  (bind_assoc := fun x _ _ => funext <| fun s => by
-    dsimp only [EStateM.instMonad, EStateM.bind]
-    match x s with
-    | .ok _ _ => rfl
-    | .error _ _ => rfl)
-  (map_const := fun _ _ => rfl)

src/Init/Control/Option.lean

@@ -10,7 +10,7 @@ import Init.Control.Except
 
 universe u v
 
-instance : ToBool (Option α) := ⟨Option.isSome⟩
+instance : ToBool (Option α) := ⟨Option.toBool⟩
 
 def OptionT (m : Type u → Type v) (α : Type u) : Type v :=
   m (Option α)
@@ -67,7 +67,7 @@ instance : MonadExceptOf Unit (OptionT m) where
   throw    := fun _ => OptionT.fail
   tryCatch := OptionT.tryCatch
 
-instance (ε : Type u) [MonadExceptOf ε m] : MonadExceptOf ε (OptionT m) where
+instance (ε : Type u) [Monad m] [MonadExceptOf ε m] : MonadExceptOf ε (OptionT m) where
   throw e           := OptionT.mk <| throwThe ε e
   tryCatch x handle := OptionT.mk <| tryCatchThe ε x handle
 

src/Init/Control/Reader.lean

@@ -32,7 +32,7 @@ instance : MonadControl m (ReaderT ρ m) where
   restoreM x _ := x
 
 @[always_inline]
-instance ReaderT.tryFinally [MonadFinally m] : MonadFinally (ReaderT ρ m) where
+instance ReaderT.tryFinally [MonadFinally m] [Monad m] : MonadFinally (ReaderT ρ m) where
   tryFinally' x h ctx := tryFinally' (x ctx) (fun a? => h a? ctx)
 
 @[reducible] def ReaderM (ρ : Type u) := ReaderT ρ Id

src/Init/Control/State.lean

@@ -87,7 +87,7 @@ protected def lift {α : Type u} (t : m α) : StateT σ m α :=
 instance : MonadLift m (StateT σ m) := ⟨StateT.lift⟩
 
 @[always_inline]
-instance (σ m) : MonadFunctor m (StateT σ m) := ⟨fun f x s => f (x s)⟩
+instance (σ m) [Monad m] : MonadFunctor m (StateT σ m) := ⟨fun f x s => f (x s)⟩
 
 @[always_inline]
 instance (ε) [MonadExceptOf ε m] : MonadExceptOf ε (StateT σ m) := {

src/Init/Control/StateCps.lean

@@ -4,7 +4,7 @@ Released under Apache 2.0 license as described in the file LICENSE.
 Authors: Leonardo de Moura
 -/
 prelude
-import Init.Control.Lawful.Basic
+import Init.Control.Lawful
 
 /-!
 The State monad transformer using CPS style.
@@ -14,18 +14,16 @@ def StateCpsT (σ : Type u) (m : Type u → Type v) (α : Type u) := (δ : Type
 
 namespace StateCpsT
 
-variable {α σ : Type u} {m : Type u → Type v}
-
 @[always_inline, inline]
-def runK (x : StateCpsT σ m α) (s : σ) (k : α → σ → m β) : m β :=
+def runK {α σ : Type u} {m : Type u → Type v}  (x : StateCpsT σ m α) (s : σ) (k : α → σ → m β) : m β :=
   x _ s k
 
 @[always_inline, inline]
-def run [Monad m] (x : StateCpsT σ m α) (s : σ) : m (α × σ) :=
+def run {α σ : Type u} {m : Type u → Type v} [Monad m] (x : StateCpsT σ m α) (s : σ) : m (α × σ) :=
   runK x s (fun a s => pure (a, s))
 
 @[always_inline, inline]
-def run' [Monad m] (x : StateCpsT σ m α) (s : σ) : m α :=
+def run' {α σ : Type u} {m : Type u → Type v}  [Monad m] (x : StateCpsT σ m α) (s : σ) : m α :=
   runK x s (fun a _ => pure a)
 
 @[always_inline]
@@ -50,29 +48,29 @@ protected def lift [Monad m] (x : m α) : StateCpsT σ m α :=
 instance [Monad m] : MonadLift m (StateCpsT σ m) where
   monadLift := StateCpsT.lift
 
-@[simp] theorem runK_pure (a : α) (s : σ) (k : α → σ → m β) : (pure a : StateCpsT σ m α).runK s k = k a s := rfl
+@[simp] theorem runK_pure {m : Type u → Type v} (a : α) (s : σ) (k : α → σ → m β) : (pure a : StateCpsT σ m α).runK s k = k a s := rfl
 
-@[simp] theorem runK_get (s : σ) (k : σ → σ → m β) : (get : StateCpsT σ m σ).runK s k = k s s := rfl
+@[simp] theorem runK_get {m : Type u → Type v} (s : σ) (k : σ → σ → m β) : (get : StateCpsT σ m σ).runK s k = k s s := rfl
 
-@[simp] theorem runK_set (s s' : σ) (k : PUnit → σ → m β) : (set s' : StateCpsT σ m PUnit).runK s k = k ⟨⟩ s' := rfl
+@[simp] theorem runK_set {m : Type u → Type v} (s s' : σ) (k : PUnit → σ → m β) : (set s' : StateCpsT σ m PUnit).runK s k = k ⟨⟩ s' := rfl
 
-@[simp] theorem runK_modify (f : σ → σ) (s : σ) (k : PUnit → σ → m β) : (modify f : StateCpsT σ m PUnit).runK s k = k ⟨⟩ (f s) := rfl
+@[simp] theorem runK_modify {m : Type u → Type v} (f : σ → σ) (s : σ) (k : PUnit → σ → m β) : (modify f : StateCpsT σ m PUnit).runK s k = k ⟨⟩ (f s) := rfl
 
-@[simp] theorem runK_lift [Monad m] (x : m α) (s : σ) (k : α → σ → m β) : (StateCpsT.lift x : StateCpsT σ m α).runK s k = x >>= (k . s) := rfl
+@[simp] theorem runK_lift {α σ : Type u} [Monad m] (x : m α) (s : σ) (k : α → σ → m β) : (StateCpsT.lift x : StateCpsT σ m α).runK s k = x >>= (k . s) := rfl
 
-@[simp] theorem runK_monadLift [Monad m] [MonadLiftT n m] (x : n α) (s : σ) (k : α → σ → m β)
+@[simp] theorem runK_monadLift {σ : Type u} [Monad m] [MonadLiftT n m] (x : n α) (s : σ) (k : α → σ → m β)
     : (monadLift x : StateCpsT σ m α).runK s k = (monadLift x : m α) >>= (k . s) := rfl
 
-@[simp] theorem runK_bind_pure (a : α) (f : α → StateCpsT σ m β) (s : σ) (k : β → σ → m γ) : (pure a >>= f).runK s k = (f a).runK s k := rfl
+@[simp] theorem runK_bind_pure {α σ : Type u} [Monad m] (a : α) (f : α → StateCpsT σ m β) (s : σ) (k : β → σ → m γ) : (pure a >>= f).runK s k = (f a).runK s k := rfl
 
-@[simp] theorem runK_bind_lift [Monad m] (x : m α) (f : α → StateCpsT σ m β) (s : σ) (k : β → σ → m γ)
+@[simp] theorem runK_bind_lift {α σ : Type u} [Monad m] (x : m α) (f : α → StateCpsT σ m β) (s : σ) (k : β → σ → m γ)
     : (StateCpsT.lift x >>= f).runK s k = x >>= fun a => (f a).runK s k := rfl
 
-@[simp] theorem runK_bind_get (f : σ → StateCpsT σ m β) (s : σ) (k : β → σ → m γ) : (get >>= f).runK s k = (f s).runK s k := rfl
+@[simp] theorem runK_bind_get {σ : Type u} [Monad m] (f : σ → StateCpsT σ m β) (s : σ) (k : β → σ → m γ) : (get >>= f).runK s k = (f s).runK s k := rfl
 
-@[simp] theorem runK_bind_set (f : PUnit → StateCpsT σ m β) (s s' : σ) (k : β → σ → m γ) : (set s' >>= f).runK s k = (f ⟨⟩).runK s' k := rfl
+@[simp] theorem runK_bind_set {σ : Type u} [Monad m] (f : PUnit → StateCpsT σ m β) (s s' : σ) (k : β → σ → m γ) : (set s' >>= f).runK s k = (f ⟨⟩).runK s' k := rfl
 
-@[simp] theorem runK_bind_modify (f : σ → σ) (g : PUnit → StateCpsT σ m β) (s : σ) (k : β → σ → m γ) : (modify f >>= g).runK s k = (g ⟨⟩).runK (f s) k := rfl
+@[simp] theorem runK_bind_modify {σ : Type u} [Monad m] (f : σ → σ) (g : PUnit → StateCpsT σ m β) (s : σ) (k : β → σ → m γ) : (modify f >>= g).runK s k = (g ⟨⟩).runK (f s) k := rfl
 
 @[simp] theorem run_eq [Monad m] (x : StateCpsT σ m α) (s : σ) : x.run s = x.runK s (fun a s => pure (a, s)) := rfl
 

src/Init/Control/StateRef.lean

@@ -34,22 +34,22 @@ protected def lift (x : m α) : StateRefT' ω σ m α :=
 
 instance [Monad m] : Monad (StateRefT' ω σ m) := inferInstanceAs (Monad (ReaderT _ _))
 instance : MonadLift m (StateRefT' ω σ m) := ⟨StateRefT'.lift⟩
-instance (σ m) : MonadFunctor m (StateRefT' ω σ m) := inferInstanceAs (MonadFunctor m (ReaderT _ _))
+instance (σ m) [Monad m] : MonadFunctor m (StateRefT' ω σ m) := inferInstanceAs (MonadFunctor m (ReaderT _ _))
 instance [Alternative m] [Monad m] : Alternative (StateRefT' ω σ m) := inferInstanceAs (Alternative (ReaderT _ _))
 
 @[inline]
-protected def get [MonadLiftT (ST ω) m] : StateRefT' ω σ m σ :=
+protected def get [Monad m] [MonadLiftT (ST ω) m] : StateRefT' ω σ m σ :=
   fun ref => ref.get
 
 @[inline]
-protected def set [MonadLiftT (ST ω) m] (s : σ) : StateRefT' ω σ m PUnit :=
+protected def set [Monad m] [MonadLiftT (ST ω) m] (s : σ) : StateRefT' ω σ m PUnit :=
   fun ref => ref.set s
 
 @[inline]
-protected def modifyGet [MonadLiftT (ST ω) m] (f : σ → α × σ) : StateRefT' ω σ m α :=
+protected def modifyGet [Monad m] [MonadLiftT (ST ω) m] (f : σ → α × σ) : StateRefT' ω σ m α :=
   fun ref => ref.modifyGet f
 
-instance [MonadLiftT (ST ω) m] : MonadStateOf σ (StateRefT' ω σ m) where
+instance [MonadLiftT (ST ω) m] [Monad m] : MonadStateOf σ (StateRefT' ω σ m) where
   get       := StateRefT'.get
   set       := StateRefT'.set
   modifyGet := StateRefT'.modifyGet

src/Init/Conv.lean

@@ -6,7 +6,7 @@ Authors: Leonardo de Moura
 Notation for operators defined at Prelude.lean
 -/
 prelude
-import Init.Tactics
+import Init.NotationExtra
 
 namespace Lean.Parser.Tactic.Conv
 
@@ -54,10 +54,6 @@ syntax (name := lhs) "lhs" : conv
 (In general, for an `n`-ary operator, it traverses into the last argument.) -/
 syntax (name := rhs) "rhs" : conv
 
-/-- Traverses into the function of a (unary) function application.
-For example, `| f a b` turns into `| f a`. (Use `arg 0` to traverse into `f`.)  -/
-syntax (name := «fun») "fun" : conv
-
 /-- Reduces the target to Weak Head Normal Form. This reduces definitions
 in "head position" until a constructor is exposed. For example, `List.map f [a, b, c]`
 weak head normalizes to `f a :: List.map f [b, c]`. -/
@@ -78,8 +74,7 @@ syntax (name := congr) "congr" : conv
 * `arg i` traverses into the `i`'th argument of the target. For example if the
   target is `f a b c d` then `arg 1` traverses to `a` and `arg 3` traverses to `c`.
 * `arg @i` is the same as `arg i` but it counts all arguments instead of just the
-  explicit arguments.
-* `arg 0` traverses into the function. If the target is `f a b c d`, `arg 0` traverses into `f`. -/
+  explicit arguments. -/
 syntax (name := arg) "arg " "@"? num : conv
 
 /-- `ext x` traverses into a binder (a `fun x => e` or `∀ x, e` expression)
@@ -156,6 +151,7 @@ match [a, b] with
 simplifies to `a`. -/
 syntax (name := simpMatch) "simp_match" : conv
 
+
 /-- Executes the given tactic block without converting `conv` goal into a regular goal. -/
 syntax (name := nestedTacticCore) "tactic'" " => " tacticSeq : conv
 
@@ -201,7 +197,7 @@ macro (name := anyGoals) tk:"any_goals " s:convSeq : conv =>
   with inaccessible names to the given names.
 * `case tag₁ | tag₂ => tac` is equivalent to `(case tag₁ => tac); (case tag₂ => tac)`.
 -/
-macro (name := case) tk:"case " args:sepBy1(caseArg, "|") arr:" => " s:convSeq : conv =>
+macro (name := case) tk:"case " args:sepBy1(caseArg, " | ") arr:" => " s:convSeq : conv =>
   `(conv| tactic' => case%$tk $args|* =>%$arr conv' => ($s); all_goals rfl)
 
 /--
@@ -210,7 +206,7 @@ has been solved after applying `tac`, nor admits the goal if `tac` failed.
 Recall that `case` closes the goal using `sorry` when `tac` fails, and
 the tactic execution is not interrupted.
 -/
-macro (name := case') tk:"case' " args:sepBy1(caseArg, "|") arr:" => " s:convSeq : conv =>
+macro (name := case') tk:"case' " args:sepBy1(caseArg, " | ") arr:" => " s:convSeq : conv =>
   `(conv| tactic' => case'%$tk $args|* =>%$arr conv' => $s)
 
 /--
@@ -307,7 +303,4 @@ Basic forms:
 -- refer to the syntax category instead of this syntax
 syntax (name := conv) "conv" (" at " ident)? (" in " (occs)? term)? " => " convSeq : tactic
 
-/-- `norm_cast` tactic in `conv` mode. -/
-syntax (name := normCast) "norm_cast" : conv
-
 end Lean.Parser.Tactic.Conv

src/Init/Core.lean

@@ -17,9 +17,7 @@ universe u v w
 at the application site itself (by comparison to the `@[inline]` attribute,
 which applies to all applications of the function).
 -/
-@[simp] def inline {α : Sort u} (a : α) : α := a
-
-theorem id_def {α : Sort u} (a : α) : id a = a := rfl
+def inline {α : Sort u} (a : α) : α := a
 
 /--
 `flip f a b` is `f b a`. It is useful for "point-free" programming,
@@ -34,32 +32,8 @@ and `flip (·<·)` is the greater-than relation.
 
 @[simp] theorem Function.comp_apply {f : β → δ} {g : α → β} {x : α} : comp f g x = f (g x) := rfl
 
-theorem Function.comp_def {α β δ} (f : β → δ) (g : α → β) : f ∘ g = fun x => f (g x) := rfl
-
 attribute [simp] namedPattern
 
-/--
-`Empty.elim : Empty → C` says that a value of any type can be constructed from
-`Empty`. This can be thought of as a compiler-checked assertion that a code path is unreachable.
-
-This is a non-dependent variant of `Empty.rec`.
--/
-@[macro_inline] def Empty.elim {C : Sort u} : Empty → C := Empty.rec
-
-/-- Decidable equality for Empty -/
-instance : DecidableEq Empty := fun a => a.elim
-
-/--
-`PEmpty.elim : Empty → C` says that a value of any type can be constructed from
-`PEmpty`. This can be thought of as a compiler-checked assertion that a code path is unreachable.
-
-This is a non-dependent variant of `PEmpty.rec`.
--/
-@[macro_inline] def PEmpty.elim {C : Sort _} : PEmpty → C := fun a => nomatch a
-
-/-- Decidable equality for PEmpty -/
-instance : DecidableEq PEmpty := fun a => a.elim
-
 /--
   Thunks are "lazy" values that are evaluated when first accessed using `Thunk.get/map/bind`.
   The value is then stored and not recomputed for all further accesses. -/
@@ -104,8 +78,6 @@ instance thunkCoe : CoeTail α (Thunk α) where
 abbrev Eq.ndrecOn.{u1, u2} {α : Sort u2} {a : α} {motive : α → Sort u1} {b : α} (h : a = b) (m : motive a) : motive b :=
   Eq.ndrec m h
 
-/-! # definitions  -/
-
 /--
 If and only if, or logical bi-implication. `a ↔ b` means that `a` implies `b` and vice versa.
 By `propext`, this implies that `a` and `b` are equal and hence any expression involving `a`
@@ -154,10 +126,6 @@ inductive PSum (α : Sort u) (β : Sort v) where
 
 @[inherit_doc] infixr:30 " ⊕' " => PSum
 
-instance {α β} [Inhabited α] : Inhabited (PSum α β) := ⟨PSum.inl default⟩
-
-instance {α β} [Inhabited β] : Inhabited (PSum α β) := ⟨PSum.inr default⟩
-
 /--
 `Sigma β`, also denoted `Σ a : α, β a` or `(a : α) × β a`, is the type of dependent pairs
 whose first component is `a : α` and whose second component is `b : β a`
@@ -165,7 +133,6 @@ whose first component is `a : α` and whose second component is `b : β a`
 It is sometimes known as the dependent sum type, since it is the type level version
 of an indexed summation.
 -/
-@[pp_using_anonymous_constructor]
 structure Sigma {α : Type u} (β : α → Type v) where
   /-- Constructor for a dependent pair. If `a : α` and `b : β a` then `⟨a, b⟩ : Sigma β`.
   (This will usually require a type ascription to determine `β`
@@ -191,7 +158,6 @@ which can cause problems for universe level unification,
 because the equation `max 1 u v = ?u + 1` has no solution in level arithmetic.
 `PSigma` is usually only used in automation that constructs pairs of arbitrary types.
 -/
-@[pp_using_anonymous_constructor]
 structure PSigma {α : Sort u} (β : α → Sort v) where
   /-- Constructor for a dependent pair. If `a : α` and `b : β a` then `⟨a, b⟩ : PSigma β`.
   (This will usually require a type ascription to determine `β`
@@ -376,70 +342,6 @@ class HasEquiv (α : Sort u) where
 
 @[inherit_doc] infix:50 " ≈ "  => HasEquiv.Equiv
 
-/-! # set notation  -/
-
-/-- Notation type class for the subset relation `⊆`. -/
-class HasSubset (α : Type u) where
-  /-- Subset relation: `a ⊆ b`  -/
-  Subset : α → α → Prop
-export HasSubset (Subset)
-
-/-- Notation type class for the strict subset relation `⊂`. -/
-class HasSSubset (α : Type u) where
-  /-- Strict subset relation: `a ⊂ b`  -/
-  SSubset : α → α → Prop
-export HasSSubset (SSubset)
-
-/-- Superset relation: `a ⊇ b`  -/
-abbrev Superset [HasSubset α] (a b : α) := Subset b a
-
-/-- Strict superset relation: `a ⊃ b`  -/
-abbrev SSuperset [HasSSubset α] (a b : α) := SSubset b a
-
-/-- Notation type class for the union operation `∪`. -/
-class Union (α : Type u) where
-  /-- `a ∪ b` is the union of`a` and `b`. -/
-  union : α → α → α
-
-/-- Notation type class for the intersection operation `∩`. -/
-class Inter (α : Type u) where
-  /-- `a ∩ b` is the intersection of`a` and `b`. -/
-  inter : α → α → α
-
-/-- Notation type class for the set difference `\`. -/
-class SDiff (α : Type u) where
-  /--
-  `a \ b` is the set difference of `a` and `b`,
-  consisting of all elements in `a` that are not in `b`.
-  -/
-  sdiff : α → α → α
-
-/-- Subset relation: `a ⊆ b`  -/
-infix:50 " ⊆ " => Subset
-
-/-- Strict subset relation: `a ⊂ b`  -/
-infix:50 " ⊂ " => SSubset
-
-/-- Superset relation: `a ⊇ b`  -/
-infix:50 " ⊇ " => Superset
-
-/-- Strict superset relation: `a ⊃ b`  -/
-infix:50 " ⊃ " => SSuperset
-
-/-- `a ∪ b` is the union of`a` and `b`. -/
-infixl:65 " ∪ " => Union.union
-
-/-- `a ∩ b` is the intersection of`a` and `b`. -/
-infixl:70 " ∩ " => Inter.inter
-
-/--
-`a \ b` is the set difference of `a` and `b`,
-consisting of all elements in `a` that are not in `b`.
--/
-infix:70 " \\ " => SDiff.sdiff
-
-/-! # collections  -/
-
 /-- `EmptyCollection α` is the typeclass which supports the notation `∅`, also written as `{}`. -/
 class EmptyCollection (α : Type u) where
   /-- `∅` or `{}` is the empty set or empty collection.
@@ -449,36 +351,6 @@ class EmptyCollection (α : Type u) where
 @[inherit_doc] notation "{" "}" => EmptyCollection.emptyCollection
 @[inherit_doc] notation "∅"     => EmptyCollection.emptyCollection
 
-/--
-Type class for the `insert` operation.
-Used to implement the `{ a, b, c }` syntax.
--/
-class Insert (α : outParam <| Type u) (γ : Type v) where
-  /-- `insert x xs` inserts the element `x` into the collection `xs`. -/
-  insert : α → γ → γ
-export Insert (insert)
-
-/--
-Type class for the `singleton` operation.
-Used to implement the `{ a, b, c }` syntax.
--/
-class Singleton (α : outParam <| Type u) (β : Type v) where
-  /-- `singleton x` is a collection with the single element `x` (notation: `{x}`). -/
-  singleton : α → β
-export Singleton (singleton)
-
-/-- `insert x ∅ = {x}` -/
-class LawfulSingleton (α : Type u) (β : Type v) [EmptyCollection β] [Insert α β] [Singleton α β] :
-    Prop where
-  /-- `insert x ∅ = {x}` -/
-  insert_emptyc_eq (x : α) : (insert x ∅ : β) = singleton x
-export LawfulSingleton (insert_emptyc_eq)
-
-/-- Type class used to implement the notation `{ a ∈ c | p a }` -/
-class Sep (α : outParam <| Type u) (γ : Type v) where
-  /-- Computes `{ a ∈ c | p a }`. -/
-  sep : (α → Prop) → γ → γ
-
 /--
 `Task α` is a primitive for asynchronous computation.
 It represents a computation that will resolve to a value of type `α`,
@@ -539,10 +411,9 @@ set_option linter.unusedVariables.funArgs false in
 be available and then calls `f` on the result.
 
 `prio`, if provided, is the priority of the task.
-If `sync` is set to true, `f` is executed on the current thread if `x` has already finished.
 -/
 @[noinline, extern "lean_task_map"]
-protected def map (f : α → β) (x : Task α) (prio := Priority.default) (sync := false) : Task β :=
+protected def map {α : Type u} {β : Type v} (f : α → β) (x : Task α) (prio := Priority.default) : Task β :=
   ⟨f x.get⟩
 
 set_option linter.unusedVariables.funArgs false in
@@ -553,11 +424,9 @@ for the value of `x` to be available and then calls `f` on the result,
 resulting in a new task which is then run for a result.
 
 `prio`, if provided, is the priority of the task.
-If `sync` is set to true, `f` is executed on the current thread if `x` has already finished.
 -/
 @[noinline, extern "lean_task_bind"]
-protected def bind (x : Task α) (f : α → Task β) (prio := Priority.default) (sync := false) :
-    Task β :=
+protected def bind {α : Type u} {β : Type v} (x : Task α) (f : α → Task β) (prio := Priority.default) : Task β :=
   ⟨(f x.get).get⟩
 
 end Task
@@ -642,7 +511,7 @@ instance : LawfulBEq String := inferInstance
 
 /-! # Logical connectives and equality -/
 
-@[inherit_doc True.intro] theorem trivial : True := ⟨⟩
+@[inherit_doc True.intro] def trivial : True := ⟨⟩
 
 theorem mt {a b : Prop} (h₁ : a → b) (h₂ : ¬b) : ¬a :=
   fun ha => h₂ (h₁ ha)
@@ -653,7 +522,9 @@ theorem not_not_intro {p : Prop} (h : p) : ¬ ¬ p :=
   fun hn : ¬ p => hn h
 
 -- proof irrelevance is built in
-theorem proof_irrel {a : Prop} (h₁ h₂ : a) : h₁ = h₂ := rfl
+theorem proofIrrel {a : Prop} (h₁ h₂ : a) : h₁ = h₂ := rfl
+
+theorem id.def {α : Sort u} (a : α) : id a = a := rfl
 
 /--
 If `h : α = β` is a proof of type equality, then `h.mp : α → β` is the induced
@@ -679,7 +550,7 @@ You can prove theorems about the resulting element by induction on `h`, since
 theorem Eq.substr {α : Sort u} {p : α → Prop} {a b : α} (h₁ : b = a) (h₂ : p a) : p b :=
   h₁ ▸ h₂
 
-@[simp] theorem cast_eq {α : Sort u} (h : α = α) (a : α) : cast h a = a :=
+theorem cast_eq {α : Sort u} (h : α = α) (a : α) : cast h a = a :=
   rfl
 
 /--
@@ -701,9 +572,8 @@ theorem Ne.elim (h : a ≠ b) : a = b → False := h
 
 theorem Ne.irrefl (h : a ≠ a) : False := h rfl
 
-theorem Ne.symm (h : a ≠ b) : b ≠ a := fun h₁ => h (h₁.symm)
-
-theorem ne_comm {α} {a b : α} : a ≠ b ↔ b ≠ a := ⟨Ne.symm, Ne.symm⟩
+theorem Ne.symm (h : a ≠ b) : b ≠ a :=
+  fun h₁ => h (h₁.symm)
 
 theorem false_of_ne : a ≠ a → False := Ne.irrefl
 
@@ -715,8 +585,8 @@ theorem ne_true_of_not : ¬p → p ≠ True :=
     have : ¬True := h ▸ hnp
     this trivial
 
-theorem true_ne_false : ¬True = False := ne_false_of_self trivial
-theorem false_ne_true : False ≠ True := fun h => h.symm ▸ trivial
+theorem true_ne_false : ¬True = False :=
+  ne_false_of_self trivial
 
 end Ne
 
@@ -739,16 +609,13 @@ theorem beq_false_of_ne [BEq α] [LawfulBEq α] {a b : α} (h : a ≠ b) : (a ==
 section
 variable {α β φ : Sort u} {a a' : α} {b b' : β} {c : φ}
 
-/-- Non-dependent recursor for `HEq` -/
-noncomputable def HEq.ndrec.{u1, u2} {α : Sort u2} {a : α} {motive : {β : Sort u2} → β → Sort u1} (m : motive a) {β : Sort u2} {b : β} (h : HEq a b) : motive b :=
+theorem HEq.ndrec.{u1, u2} {α : Sort u2} {a : α} {motive : {β : Sort u2} → β → Sort u1} (m : motive a) {β : Sort u2} {b : β} (h : HEq a b) : motive b :=
   h.rec m
 
-/-- `HEq.ndrec` variant -/
-noncomputable def HEq.ndrecOn.{u1, u2} {α : Sort u2} {a : α} {motive : {β : Sort u2} → β → Sort u1} {β : Sort u2} {b : β} (h : HEq a b) (m : motive a) : motive b :=
+theorem HEq.ndrecOn.{u1, u2} {α : Sort u2} {a : α} {motive : {β : Sort u2} → β → Sort u1} {β : Sort u2} {b : β} (h : HEq a b) (m : motive a) : motive b :=
   h.rec m
 
-/-- `HEq.ndrec` variant -/
-noncomputable def HEq.elim {α : Sort u} {a : α} {p : α → Sort v} {b : α} (h₁ : HEq a b) (h₂ : p a) : p b :=
+theorem HEq.elim {α : Sort u} {a : α} {p : α → Sort v} {b : α} (h₁ : HEq a b) (h₂ : p a) : p b :=
   eq_of_heq h₁ ▸ h₂
 
 theorem HEq.subst {p : (T : Sort u) → T → Prop} (h₁ : HEq a b) (h₂ : p α a) : p β b :=
@@ -796,31 +663,22 @@ theorem Iff.refl (a : Prop) : a ↔ a :=
 protected theorem Iff.rfl {a : Prop} : a ↔ a :=
   Iff.refl a
 
-macro_rules | `(tactic| rfl) => `(tactic| exact Iff.rfl)
-
-theorem Iff.of_eq (h : a = b) : a ↔ b := h ▸ Iff.rfl
-
 theorem Iff.trans (h₁ : a ↔ b) (h₂ : b ↔ c) : a ↔ c :=
-  Iff.intro (h₂.mp ∘ h₁.mp) (h₁.mpr ∘ h₂.mpr)
+  Iff.intro
+    (fun ha => Iff.mp h₂ (Iff.mp h₁ ha))
+    (fun hc => Iff.mpr h₁ (Iff.mpr h₂ hc))
 
--- This is needed for `calc` to work with `iff`.
-instance : Trans Iff Iff Iff where
-  trans := Iff.trans
+theorem Iff.symm (h : a ↔ b) : b ↔ a :=
+  Iff.intro (Iff.mpr h) (Iff.mp h)
 
-theorem Eq.comm {a b : α} : a = b ↔ b = a := Iff.intro Eq.symm Eq.symm
-theorem eq_comm {a b : α} : a = b ↔ b = a := Eq.comm
+theorem Iff.comm : (a ↔ b) ↔ (b ↔ a) :=
+  Iff.intro Iff.symm Iff.symm
 
-theorem Iff.symm (h : a ↔ b) : b ↔ a := Iff.intro h.mpr h.mp
-theorem Iff.comm: (a ↔ b) ↔ (b ↔ a) := Iff.intro Iff.symm Iff.symm
-theorem iff_comm : (a ↔ b) ↔ (b ↔ a) := Iff.comm
+theorem Iff.of_eq (h : a = b) : a ↔ b :=
+  h ▸ Iff.refl _
 
-theorem And.symm : a ∧ b → b ∧ a := fun ⟨ha, hb⟩ => ⟨hb, ha⟩
-theorem And.comm : a ∧ b ↔ b ∧ a := Iff.intro And.symm And.symm
-theorem and_comm : a ∧ b ↔ b ∧ a := And.comm
-
-theorem Or.symm : a ∨ b → b ∨ a := .rec .inr .inl
-theorem Or.comm : a ∨ b ↔ b ∨ a := Iff.intro Or.symm Or.symm
-theorem or_comm : a ∨ b ↔ b ∨ a := Or.comm
+theorem And.comm : a ∧ b ↔ b ∧ a := by
+  constructor <;> intro ⟨h₁, h₂⟩ <;> exact ⟨h₂, h₁⟩
 
 /-! # Exists -/
 
@@ -1020,13 +878,8 @@ protected theorem Subsingleton.helim {α β : Sort u} [h₁ : Subsingleton α] (
   apply heq_of_eq
   apply Subsingleton.elim
 
-instance (p : Prop) : Subsingleton p := ⟨fun a b => proof_irrel a b⟩
-
-instance : Subsingleton Empty  := ⟨(·.elim)⟩
-instance : Subsingleton PEmpty := ⟨(·.elim)⟩
-
-instance [Subsingleton α] [Subsingleton β] : Subsingleton (α × β) :=
-  ⟨fun {..} {..} => by congr <;> apply Subsingleton.elim⟩
+instance (p : Prop) : Subsingleton p :=
+  ⟨fun a b => proofIrrel a b⟩
 
 instance (p : Prop) : Subsingleton (Decidable p) :=
   Subsingleton.intro fun
@@ -1037,9 +890,6 @@ instance (p : Prop) : Subsingleton (Decidable p) :=
       | isTrue t₂  => absurd t₂ f₁
       | isFalse _  => rfl
 
-example [Subsingleton α] (p : α → Prop) : Subsingleton (Subtype p) :=
-  ⟨fun ⟨x, _⟩ ⟨y, _⟩ => by congr; exact Subsingleton.elim x y⟩
-
 theorem recSubsingleton
      {p : Prop} [h : Decidable p]
      {h₁ : p → Sort u}
@@ -1114,6 +964,9 @@ theorem eta (a : {x // p x}) (h : p (val a)) : mk (val a) h = a := by
   cases a
   exact rfl
 
+instance {α : Type u} {p : α → Prop} {a : α} (h : p a) : Inhabited {x // p x} where
+  default := ⟨a, h⟩
+
 instance {α : Type u} {p : α → Prop} [DecidableEq α] : DecidableEq {x : α // p x} :=
   fun ⟨a, h₁⟩ ⟨b, h₂⟩ =>
     if h : a = b then isTrue (by subst h; exact rfl)
@@ -1173,7 +1026,7 @@ def Prod.lexLt [LT α] [LT β] (s : α × β) (t : α × β) : Prop :=
   s.1 < t.1 ∨ (s.1 = t.1 ∧ s.2 < t.2)
 
 instance Prod.lexLtDec
-    [LT α] [LT β] [DecidableEq α]
+    [LT α] [LT β] [DecidableEq α] [DecidableEq β]
     [(a b : α) → Decidable (a < b)] [(a b : β) → Decidable (a < b)]
     : (s t : α × β) → Decidable (Prod.lexLt s t) :=
   fun _ _ => inferInstanceAs (Decidable (_ ∨ _))
@@ -1191,11 +1044,6 @@ def Prod.map {α₁ : Type u₁} {α₂ : Type u₂} {β₁ : Type v₁} {β₂
     (f : α₁ → α₂) (g : β₁ → β₂) : α₁ × β₁ → α₂ × β₂
   | (a, b) => (f a, g b)
 
-@[simp] theorem Prod.map_apply (f : α → β) (g : γ → δ) (x) (y) :
-    Prod.map f g (x, y) = (f x, g y) := rfl
-@[simp] theorem Prod.map_fst (f : α → β) (g : γ → δ) (x) : (Prod.map f g x).1 = f x.1 := rfl
-@[simp] theorem Prod.map_snd (f : α → β) (g : γ → δ) (x) : (Prod.map f g x).2 = g x.2 := rfl
-
 /-! # Dependent products -/
 
 theorem ex_of_PSigma {α : Type u} {p : α → Prop} : (PSigma (fun x => p x)) → Exists (fun x => p x)
@@ -1310,6 +1158,7 @@ gen_injective_theorems% Fin
 gen_injective_theorems% Array
 gen_injective_theorems% Sum
 gen_injective_theorems% PSum
+gen_injective_theorems% Nat
 gen_injective_theorems% Option
 gen_injective_theorems% List
 gen_injective_theorems% Except
@@ -1317,126 +1166,15 @@ gen_injective_theorems% EStateM.Result
 gen_injective_theorems% Lean.Name
 gen_injective_theorems% Lean.Syntax
 
-theorem Nat.succ.inj {m n : Nat} : m.succ = n.succ → m = n :=
-  fun x => Nat.noConfusion x id
-
-theorem Nat.succ.injEq (u v : Nat) : (u.succ = v.succ) = (u = v) :=
-  Eq.propIntro Nat.succ.inj (congrArg Nat.succ)
-
 @[simp] theorem beq_iff_eq [BEq α] [LawfulBEq α] (a b : α) : a == b ↔ a = b :=
   ⟨eq_of_beq, by intro h; subst h; exact LawfulBEq.rfl⟩
 
-/-! # Prop lemmas -/
-
-/-- *Ex falso* for negation: from `¬a` and `a` anything follows. This is the same as `absurd` with
-the arguments flipped, but it is in the `Not` namespace so that projection notation can be used. -/
-def Not.elim {α : Sort _} (H1 : ¬a) (H2 : a) : α := absurd H2 H1
-
-/-- Non-dependent eliminator for `And`. -/
-abbrev And.elim (f : a → b → α) (h : a ∧ b) : α := f h.left h.right
-
-/-- Non-dependent eliminator for `Iff`. -/
-def Iff.elim (f : (a → b) → (b → a) → α) (h : a ↔ b) : α := f h.mp h.mpr
+/-! # Quotients -/
 
 /-- Iff can now be used to do substitutions in a calculation -/
 theorem Iff.subst {a b : Prop} {p : Prop → Prop} (h₁ : a ↔ b) (h₂ : p a) : p b :=
   Eq.subst (propext h₁) h₂
 
-theorem Not.intro {a : Prop} (h : a → False) : ¬a := h
-
-theorem Not.imp {a b : Prop} (H2 : ¬b) (H1 : a → b) : ¬a := mt H1 H2
-
-theorem not_congr (h : a ↔ b) : ¬a ↔ ¬b := ⟨mt h.2, mt h.1⟩
-
-theorem not_not_not : ¬¬¬a ↔ ¬a := ⟨mt not_not_intro, not_not_intro⟩
-
-theorem iff_of_true (ha : a) (hb : b) : a ↔ b := Iff.intro (fun _ => hb) (fun _ => ha)
-theorem iff_of_false (ha : ¬a) (hb : ¬b) : a ↔ b := Iff.intro ha.elim hb.elim
-
-theorem iff_true_left  (ha : a) : (a ↔ b) ↔ b := Iff.intro (·.mp ha) (iff_of_true ha)
-theorem iff_true_right (ha : a) : (b ↔ a) ↔ b := Iff.comm.trans (iff_true_left ha)
-
-theorem iff_false_left  (ha : ¬a) : (a ↔ b) ↔ ¬b := Iff.intro (mt ·.mpr ha) (iff_of_false ha)
-theorem iff_false_right (ha : ¬a) : (b ↔ a) ↔ ¬b := Iff.comm.trans (iff_false_left ha)
-
-theorem of_iff_true    (h : a ↔ True) : a := h.mpr trivial
-theorem iff_true_intro (h : a) : a ↔ True := iff_of_true h trivial
-
-theorem not_of_iff_false : (p ↔ False) → ¬p := Iff.mp
-theorem iff_false_intro (h : ¬a) : a ↔ False := iff_of_false h id
-
-theorem not_iff_false_intro (h : a) : ¬a ↔ False := iff_false_intro (not_not_intro h)
-theorem not_true : (¬True) ↔ False := iff_false_intro (not_not_intro trivial)
-
-theorem not_false_iff : (¬False) ↔ True := iff_true_intro not_false
-
-theorem Eq.to_iff : a = b → (a ↔ b) := Iff.of_eq
-theorem iff_of_eq : a = b → (a ↔ b) := Iff.of_eq
-theorem neq_of_not_iff : ¬(a ↔ b) → a ≠ b := mt Iff.of_eq
-
-theorem iff_iff_eq : (a ↔ b) ↔ a = b := Iff.intro propext Iff.of_eq
-@[simp] theorem eq_iff_iff : (a = b) ↔ (a ↔ b) := iff_iff_eq.symm
-
-theorem eq_self_iff_true (a : α)  : a = a ↔ True  := iff_true_intro rfl
-theorem ne_self_iff_false (a : α) : a ≠ a ↔ False := not_iff_false_intro rfl
-
-theorem false_of_true_iff_false (h : True ↔ False) : False := h.mp trivial
-theorem false_of_true_eq_false  (h : True = False) : False := false_of_true_iff_false (Iff.of_eq h)
-
-theorem true_eq_false_of_false : False → (True = False) := False.elim
-
-theorem iff_def  : (a ↔ b) ↔ (a → b) ∧ (b → a) := iff_iff_implies_and_implies a b
-theorem iff_def' : (a ↔ b) ↔ (b → a) ∧ (a → b) := Iff.trans iff_def And.comm
-
-theorem true_iff_false : (True ↔ False) ↔ False := iff_false_intro (·.mp  True.intro)
-theorem false_iff_true : (False ↔ True) ↔ False := iff_false_intro (·.mpr True.intro)
-
-theorem iff_not_self : ¬(a ↔ ¬a) | H => let f h := H.1 h h; f (H.2 f)
-theorem heq_self_iff_true (a : α) : HEq a a ↔ True := iff_true_intro HEq.rfl
-
-/-! ## implies -/
-
-theorem not_not_of_not_imp : ¬(a → b) → ¬¬a := mt Not.elim
-
-theorem not_of_not_imp {a : Prop} : ¬(a → b) → ¬b := mt fun h _ => h
-
-@[simp] theorem imp_not_self : (a → ¬a) ↔ ¬a := Iff.intro (fun h ha => h ha ha) (fun h _ => h)
-
-theorem imp_intro {α β : Prop} (h : α) : β → α := fun _ => h
-
-theorem imp_imp_imp {a b c d : Prop} (h₀ : c → a) (h₁ : b → d) : (a → b) → (c → d) := (h₁ ∘ · ∘ h₀)
-
-theorem imp_iff_right {a : Prop} (ha : a) : (a → b) ↔ b := Iff.intro (· ha) (fun a _ => a)
-
--- This is not marked `@[simp]` because we have `implies_true : (α → True) = True`
-theorem imp_true_iff (α : Sort u) : (α → True) ↔ True := iff_true_intro (fun _ => trivial)
-
-theorem false_imp_iff (a : Prop) : (False → a) ↔ True := iff_true_intro False.elim
-
-theorem true_imp_iff (α : Prop) : (True → α) ↔ α := imp_iff_right True.intro
-
-@[simp high] theorem imp_self : (a → a) ↔ True := iff_true_intro id
-
-@[simp] theorem imp_false : (a → False) ↔ ¬a := Iff.rfl
-
-theorem imp.swap : (a → b → c) ↔ (b → a → c) := Iff.intro flip flip
-
-theorem imp_not_comm : (a → ¬b) ↔ (b → ¬a) := imp.swap
-
-theorem imp_congr_left (h : a ↔ b) : (a → c) ↔ (b → c) := Iff.intro (· ∘ h.mpr) (· ∘ h.mp)
-
-theorem imp_congr_right (h : a → (b ↔ c)) : (a → b) ↔ (a → c) :=
-  Iff.intro (fun hab ha => (h ha).mp (hab ha)) (fun hcd ha => (h ha).mpr (hcd ha))
-
-theorem imp_congr_ctx (h₁ : a ↔ c) (h₂ : c → (b ↔ d)) : (a → b) ↔ (c → d) :=
-  Iff.trans (imp_congr_left h₁) (imp_congr_right h₂)
-
-theorem imp_congr (h₁ : a ↔ c) (h₂ : b ↔ d) : (a → b) ↔ (c → d) := imp_congr_ctx h₁ fun _ => h₂
-
-theorem imp_iff_not (hb : ¬b) : a → b ↔ ¬a := imp_congr_right fun _ => iff_false_intro hb
-
-/-! # Quotients -/
-
 namespace Quot
 /--
 The **quotient axiom**, or at least the nontrivial part of the quotient
@@ -1603,7 +1341,7 @@ protected def mk' {α : Sort u} [s : Setoid α] (a : α) : Quotient s :=
 The analogue of `Quot.sound`: If `a` and `b` are related by the equivalence relation,
 then they have equal equivalence classes.
 -/
-theorem sound {α : Sort u} {s : Setoid α} {a b : α} : a ≈ b → Quotient.mk s a = Quotient.mk s b :=
+def sound {α : Sort u} {s : Setoid α} {a b : α} : a ≈ b → Quotient.mk s a = Quotient.mk s b :=
   Quot.sound
 
 /--
@@ -1942,108 +1680,40 @@ So, you are mainly losing the capability of type checking your development using
 -/
 axiom ofReduceNat (a b : Nat) (h : reduceNat a = b) : a = b
 
-end Lean
-
-@[simp] theorem ge_iff_le [LE α] {x y : α} : x ≥ y ↔ y ≤ x := Iff.rfl
-
-@[simp] theorem gt_iff_lt [LT α] {x y : α} : x > y ↔ y < x := Iff.rfl
-
-theorem le_of_eq_of_le {a b c : α} [LE α] (h₁ : a = b) (h₂ : b ≤ c) : a ≤ c := h₁ ▸ h₂
-
-theorem le_of_le_of_eq {a b c : α} [LE α] (h₁ : a ≤ b) (h₂ : b = c) : a ≤ c := h₂ ▸ h₁
-
-theorem lt_of_eq_of_lt {a b c : α} [LT α] (h₁ : a = b) (h₂ : b < c) : a < c := h₁ ▸ h₂
-
-theorem lt_of_lt_of_eq {a b c : α} [LT α] (h₁ : a < b) (h₂ : b = c) : a < c := h₂ ▸ h₁
-
-namespace Std
-variable {α : Sort u}
-
 /--
-`Associative op` indicates `op` is an associative operation,
-i.e. `(a ∘ b) ∘ c = a ∘ (b ∘ c)`.
+`IsAssociative op` says that `op` is an associative operation,
+i.e. `(a ∘ b) ∘ c = a ∘ (b ∘ c)`. It is used by the `ac_rfl` tactic.
 -/
-class Associative (op : α → α → α) : Prop where
+class IsAssociative {α : Sort u} (op : α → α → α) where
   /-- An associative operation satisfies `(a ∘ b) ∘ c = a ∘ (b ∘ c)`. -/
   assoc : (a b c : α) → op (op a b) c = op a (op b c)
 
 /--
-`Commutative op` says that `op` is a commutative operation,
-i.e. `a ∘ b = b ∘ a`.
+`IsCommutative op` says that `op` is a commutative operation,
+i.e. `a ∘ b = b ∘ a`. It is used by the `ac_rfl` tactic.
 -/
-class Commutative (op : α → α → α) : Prop where
+class IsCommutative {α : Sort u} (op : α → α → α) where
   /-- A commutative operation satisfies `a ∘ b = b ∘ a`. -/
   comm : (a b : α) → op a b = op b a
 
 /--
-`IdempotentOp op` indicates `op` is an idempotent binary operation.
-i.e. `a ∘ a = a`.
+`IsIdempotent op` says that `op` is an idempotent operation,
+i.e. `a ∘ a = a`. It is used by the `ac_rfl` tactic
+(which also simplifies up to idempotence when available).
 -/
-class IdempotentOp (op : α → α → α) : Prop where
+class IsIdempotent {α : Sort u} (op : α → α → α) where
   /-- An idempotent operation satisfies `a ∘ a = a`. -/
   idempotent : (x : α) → op x x = x
 
 /--
-`LeftIdentify op o` indicates `o` is a left identity of `op`.
-
-This class does not require a proof that `o` is an identity, and
-is used primarily for infering the identity using class resoluton.
+`IsNeutral op e` says that `e` is a neutral operation for `op`,
+i.e. `a ∘ e = a = e ∘ a`. It is used by the `ac_rfl` tactic
+(which also simplifies neutral elements when available).
 -/
-class LeftIdentity (op : α → β → β) (o : outParam α) : Prop
+class IsNeutral {α : Sort u} (op : α → α → α) (neutral : α) where
+  /-- A neutral element can be cancelled on the left: `e ∘ a = a`. -/
+  left_neutral : (a : α) → op neutral a = a
+  /-- A neutral element can be cancelled on the right: `a ∘ e = a`. -/
+  right_neutral : (a : α) → op a neutral = a
 
-/--
-`LawfulLeftIdentify op o` indicates `o` is a verified left identity of
-`op`.
--/
-class LawfulLeftIdentity (op : α → β → β) (o : outParam α) extends LeftIdentity op o : Prop where
-  /-- Left identity `o` is an identity. -/
-  left_id : ∀ a, op o a = a
-
-/--
-`RightIdentify op o` indicates `o` is a right identity `o` of `op`.
-
-This class does not require a proof that `o` is an identity, and is used
-primarily for infering the identity using class resoluton.
--/
-class RightIdentity (op : α → β → α) (o : outParam β) : Prop
-
-/--
-`LawfulRightIdentify op o` indicates `o` is a verified right identity of
-`op`.
--/
-class LawfulRightIdentity (op : α → β → α) (o : outParam β) extends RightIdentity op o : Prop where
-  /-- Right identity `o` is an identity. -/
-  right_id : ∀ a, op a o = a
-
-/--
-`Identity op o` indicates `o` is a left and right identity of `op`.
-
-This class does not require a proof that `o` is an identity, and is used
-primarily for infering the identity using class resoluton.
--/
-class Identity (op : α → α → α) (o : outParam α) extends LeftIdentity op o, RightIdentity op o : Prop
-
-/--
-`LawfulIdentity op o` indicates `o` is a verified left and right
-identity of `op`.
--/
-class LawfulIdentity (op : α → α → α) (o : outParam α) extends Identity op o, LawfulLeftIdentity op o, LawfulRightIdentity op o : Prop
-
-/--
-`LawfulCommIdentity` can simplify defining instances of `LawfulIdentity`
-on commutative functions by requiring only a left or right identity
-proof.
-
-This class is intended for simplifying defining instances of
-`LawfulIdentity` and functions needed commutative operations with
-identity should just add a `LawfulIdentity` constraint.
--/
-class LawfulCommIdentity (op : α → α → α) (o : outParam α) [hc : Commutative op] extends LawfulIdentity op o : Prop where
-  left_id a := Eq.trans (hc.comm o a) (right_id a)
-  right_id a := Eq.trans (hc.comm a o) (left_id a)
-
-instance : Commutative Or := ⟨fun _ _ => propext or_comm⟩
-instance : Commutative And := ⟨fun _ _ => propext and_comm⟩
-instance : Commutative Iff := ⟨fun _ _ => propext iff_comm⟩
-
-end Std
+end Lean

src/Init/Data.lean

@@ -6,15 +6,11 @@ Authors: Leonardo de Moura
 prelude
 import Init.Data.Basic
 import Init.Data.Nat
-import Init.Data.Bool
-import Init.Data.BitVec
-import Init.Data.Cast
 import Init.Data.Char
 import Init.Data.String
 import Init.Data.List
 import Init.Data.Int
 import Init.Data.Array
-import Init.Data.Array.Subarray.Split
 import Init.Data.ByteArray
 import Init.Data.FloatArray
 import Init.Data.Fin
@@ -33,5 +29,3 @@ import Init.Data.Prod
 import Init.Data.AC
 import Init.Data.Queue
 import Init.Data.Channel
-import Init.Data.Cast
-import Init.Data.Sum

src/Init/Data/AC.lean

@@ -14,17 +14,15 @@ inductive Expr
   | op (lhs rhs : Expr)
   deriving Inhabited, Repr, BEq
 
-open Std
-
 structure Variable {α : Sort u} (op : α → α → α) : Type u where
   value : α
-  neutral : Option $ PLift (LawfulIdentity op value)
+  neutral : Option $ IsNeutral op value
 
 structure Context (α : Sort u) where
   op : α → α → α
-  assoc : Associative op
-  comm : Option $ PLift $ Commutative op
-  idem : Option $ PLift $ IdempotentOp op
+  assoc : IsAssociative op
+  comm : Option $ IsCommutative op
+  idem : Option $ IsIdempotent op
   vars : List (Variable op)
   arbitrary : α
 
@@ -106,7 +104,7 @@ def norm [info : ContextInformation α] (ctx : α) (e : Expr) : List Nat :=
   let xs := if info.isComm ctx then sort xs else xs
   if info.isIdem ctx then mergeIdem xs else xs
 
-noncomputable def List.two_step_induction
+theorem List.two_step_induction
   {motive : List Nat → Sort u}
   (l : List Nat)
   (empty : motive [])
@@ -130,14 +128,7 @@ theorem Context.mergeIdem_head2 (h : x ≠ y) : mergeIdem (x :: y :: ys) = x ::
   simp [mergeIdem, mergeIdem.loop, h]
 
 theorem Context.evalList_mergeIdem (ctx : Context α) (h : ContextInformation.isIdem ctx) (e : List Nat) : evalList α ctx (mergeIdem e) = evalList α ctx e := by
-  have h : IdempotentOp ctx.op := by
-    simp [ContextInformation.isIdem, Option.isSome] at h;
-    match h₂ : ctx.idem with
-    | none =>
-      simp [h₂] at h
-    | some val =>
-      simp [h₂] at h
-      exact val.down
+  have h : IsIdempotent ctx.op := by simp [ContextInformation.isIdem, Option.isSome] at h; cases h₂ : ctx.idem <;> simp [h₂] at h; assumption
   induction e using List.two_step_induction with
   | empty => rfl
   | single => rfl
@@ -146,22 +137,22 @@ theorem Context.evalList_mergeIdem (ctx : Context α) (h : ContextInformation.is
     | nil =>
       simp [mergeIdem, mergeIdem.loop]
       split
-      next h₂ => simp [evalList, h₂, h.1, EvalInformation.evalOp]
-      next => rfl
+      case inl h₂ => simp [evalList, h₂, h.1, EvalInformation.evalOp]
+      rfl
     | cons z zs =>
       by_cases h₂ : x = y
-      case pos =>
+      case inl =>
         rw [h₂, mergeIdem_head, ih]
         simp [evalList, ←ctx.assoc.1, h.1, EvalInformation.evalOp]
-      case neg =>
+      case inr =>
         rw [mergeIdem_head2]
         by_cases h₃ : y = z
-        case pos =>
+        case inl =>
           simp [mergeIdem_head, h₃, evalList]
           cases h₄ : mergeIdem (z :: zs) with
           | nil => apply absurd h₄; apply mergeIdem_nonEmpty; simp
           | cons u us => simp_all [mergeIdem, mergeIdem.loop, evalList]
-        case neg =>
+        case inr =>
           simp [mergeIdem_head2, h₃, evalList] at *
           rw [ih]
         assumption
@@ -178,7 +169,7 @@ theorem Context.sort_loop_nonEmpty (xs : List Nat) (h : xs ≠ []) : sort.loop x
 
 theorem Context.evalList_insert
   (ctx : Context α)
-  (h : Commutative ctx.op)
+  (h : IsCommutative ctx.op)
   (x : Nat)
   (xs : List Nat)
   : evalList α ctx (insert x xs) = evalList α ctx (x::xs) := by
@@ -191,15 +182,15 @@ theorem Context.evalList_insert
     . simp [evalList, h.1, EvalInformation.evalOp]
   | step y z zs ih =>
     simp [insert] at *; split
-    next => rfl
-    next =>
+    case inl => rfl
+    case inr =>
       split
-      next => simp [evalList, EvalInformation.evalOp]; rw [h.1, ctx.assoc.1, h.1 (evalList _ _ _)]
-      next => simp_all [evalList, EvalInformation.evalOp]; rw [h.1, ctx.assoc.1, h.1 (evalList _ _ _)]
+      case inl => simp [evalList, EvalInformation.evalOp]; rw [h.1, ctx.assoc.1, h.1 (evalList _ _ _)]
+      case inr => simp_all [evalList, EvalInformation.evalOp]; rw [h.1, ctx.assoc.1, h.1 (evalList _ _ _)]
 
 theorem Context.evalList_sort_congr
   (ctx : Context α)
-  (h : Commutative ctx.op)
+  (h : IsCommutative ctx.op)
   (h₂ : evalList α ctx a = evalList α ctx b)
   (h₃ : a ≠ [])
   (h₄ : b ≠ [])
@@ -218,7 +209,7 @@ theorem Context.evalList_sort_congr
 
 theorem Context.evalList_sort_loop_swap
   (ctx : Context α)
-  (h : Commutative ctx.op)
+  (h : IsCommutative ctx.op)
   (xs ys : List Nat)
   : evalList α ctx (sort.loop xs (y::ys)) = evalList α ctx (sort.loop (y::xs) ys) := by
   induction ys generalizing y xs with
@@ -233,7 +224,7 @@ theorem Context.evalList_sort_loop_swap
 
 theorem Context.evalList_sort_cons
   (ctx : Context α)
-  (h : Commutative ctx.op)
+  (h : IsCommutative ctx.op)
   (x : Nat)
   (xs : List Nat)
   : evalList α ctx (sort (x :: xs)) = evalList α ctx (x :: sort xs) := by
@@ -256,14 +247,7 @@ theorem Context.evalList_sort_cons
     all_goals simp [insert_nonEmpty]
 
 theorem Context.evalList_sort (ctx : Context α) (h : ContextInformation.isComm ctx) (e : List Nat) : evalList α ctx (sort e) = evalList α ctx e := by
-  have h : Commutative ctx.op := by
-    simp [ContextInformation.isComm, Option.isSome] at h
-    match h₂ : ctx.comm with
-    | none =>
-      simp only [h₂] at h
-    | some val =>
-      simp [h₂] at h
-      exact val.down
+  have h : IsCommutative ctx.op := by simp [ContextInformation.isComm, Option.isSome] at h; cases h₂ : ctx.comm <;> simp [h₂] at h; assumption
   induction e using List.two_step_induction with
   | empty => rfl
   | single => rfl
@@ -285,12 +269,10 @@ theorem Context.toList_nonEmpty (e : Expr) : e.toList ≠ [] := by
 theorem Context.unwrap_isNeutral
   {ctx : Context α}
   {x : Nat}
-  : ContextInformation.isNeutral ctx x = true → LawfulIdentity (EvalInformation.evalOp ctx) (EvalInformation.evalVar (β := α) ctx x) := by
+  : ContextInformation.isNeutral ctx x = true → IsNeutral (EvalInformation.evalOp ctx) (EvalInformation.evalVar (β := α) ctx x) := by
   simp [ContextInformation.isNeutral, Option.isSome, EvalInformation.evalOp, EvalInformation.evalVar]
   match (var ctx x).neutral with
-  | some hn =>
-    intro
-    exact hn.down
+  | some hn => intro; assumption
   | none => intro; contradiction
 
 theorem Context.evalList_removeNeutrals (ctx : Context α) (e : List Nat) : evalList α ctx (removeNeutrals ctx e) = evalList α ctx e := by
@@ -301,12 +283,10 @@ theorem Context.evalList_removeNeutrals (ctx : Context α) (e : List Nat) : eval
     case h_1 => rfl
     case h_2 h => split at h <;> simp_all
   | step x y ys ih =>
-    cases h₁ : ContextInformation.isNeutral ctx x <;>
-    cases h₂ : ContextInformation.isNeutral ctx y <;>
-    cases h₃ : removeNeutrals.loop ctx ys
+    cases h₁ : ContextInformation.isNeutral ctx x <;> cases h₂ : ContextInformation.isNeutral ctx y <;> cases h₃ : removeNeutrals.loop ctx ys
     <;> simp [removeNeutrals, removeNeutrals.loop, h₁, h₂, h₃, evalList, ←ih]
-    <;> (try simp [unwrap_isNeutral h₂ |>.right_id])
-    <;> (try simp [unwrap_isNeutral h₁ |>.left_id])
+    <;> (try simp [unwrap_isNeutral h₂ |>.2])
+    <;> (try simp [unwrap_isNeutral h₁ |>.1])
 
 theorem Context.evalList_append
   (ctx : Context α)

src/Init/Data/Array.lean

@@ -11,4 +11,3 @@ import Init.Data.Array.InsertionSort
 import Init.Data.Array.DecidableEq
 import Init.Data.Array.Mem
 import Init.Data.Array.BasicAux
-import Init.Data.Array.Lemmas

src/Init/Data/Array/Basic.lean

@@ -10,7 +10,7 @@ import Init.Data.Fin.Basic
 import Init.Data.UInt.Basic
 import Init.Data.Repr
 import Init.Data.ToString.Basic
-import Init.GetElem
+import Init.Util
 universe u v w
 
 namespace Array
@@ -21,22 +21,6 @@ def mkArray {α : Type u} (n : Nat) (v : α) : Array α := {
   data := List.replicate n v
 }
 
-/--
-`ofFn f` with `f : Fin n → α` returns the list whose ith element is `f i`.
-```
-ofFn f = #[f 0, f 1, ... , f(n - 1)]
-``` -/
-def ofFn {n} (f : Fin n → α) : Array α := go 0 (mkEmpty n) where
-  /-- Auxiliary for `ofFn`. `ofFn.go f i acc = acc ++ #[f i, ..., f(n - 1)]` -/
-  go (i : Nat) (acc : Array α) : Array α :=
-    if h : i < n then go (i+1) (acc.push (f ⟨i, h⟩)) else acc
-termination_by n - i
-decreasing_by simp_wf; decreasing_trivial_pre_omega
-
-/-- The array `#[0, 1, ..., n - 1]`. -/
-def range (n : Nat) : Array Nat :=
-  n.fold (flip Array.push) (mkEmpty n)
-
 @[simp] theorem size_mkArray (n : Nat) (v : α) : (mkArray n v).size = n :=
   List.length_replicate ..
 
@@ -44,7 +28,7 @@ instance : EmptyCollection (Array α) := ⟨Array.empty⟩
 instance : Inhabited (Array α) where
   default := Array.empty
 
-@[simp] def isEmpty (a : Array α) : Bool :=
+def isEmpty (a : Array α) : Bool :=
   a.size = 0
 
 def singleton (v : α) : Array α :=
@@ -53,15 +37,13 @@ def singleton (v : α) : Array α :=
 /-- Low-level version of `fget` which is as fast as a C array read.
    `Fin` values are represented as tag pointers in the Lean runtime. Thus,
    `fget` may be slightly slower than `uget`. -/
-@[extern "lean_array_uget", simp]
+@[extern "lean_array_uget"]
 def uget (a : @& Array α) (i : USize) (h : i.toNat < a.size) : α :=
   a[i.toNat]
 
 instance : GetElem (Array α) USize α fun xs i => i.toNat < xs.size where
   getElem xs i h := xs.uget i h
 
-instance : LawfulGetElem (Array α) USize α fun xs i => i.toNat < xs.size where
-
 def back [Inhabited α] (a : Array α) : α :=
   a.get! (a.size - 1)
 
@@ -89,12 +71,6 @@ abbrev getLit {α : Type u} {n : Nat} (a : Array α) (i : Nat) (h₁ : a.size =
 def uset (a : Array α) (i : USize) (v : α) (h : i.toNat < a.size) : Array α :=
   a.set ⟨i.toNat, h⟩ v
 
-/--
-Swaps two entries in an array.
-
-This will perform the update destructively provided that `a` has a reference
-count of 1 when called.
--/
 @[extern "lean_array_fswap"]
 def swap (a : Array α) (i j : @& Fin a.size) : Array α :=
   let v₁ := a.get i
@@ -102,18 +78,12 @@ def swap (a : Array α) (i j : @& Fin a.size) : Array α :=
   let a'  := a.set i v₂
   a'.set (size_set a i v₂ ▸ j) v₁
 
-/--
-Swaps two entries in an array, or panics if either index is out of bounds.
-
-This will perform the update destructively provided that `a` has a reference
-count of 1 when called.
--/
 @[extern "lean_array_swap"]
 def swap! (a : Array α) (i j : @& Nat) : Array α :=
   if h₁ : i < a.size then
   if h₂ : j < a.size then swap a ⟨i, h₁⟩ ⟨j, h₂⟩
-  else a
-  else a
+  else panic! "index out of bounds"
+  else panic! "index out of bounds"
 
 @[inline] def swapAt (a : Array α) (i : Fin a.size) (v : α) : α × Array α :=
   let e := a.get i
@@ -306,9 +276,8 @@ def mapM {α : Type u} {β : Type v} {m : Type v → Type w} [Monad m] (f : α
       map (i+1) (r.push (← f as[i]))
     else
       pure r
-  termination_by as.size - i
-  decreasing_by simp_wf; decreasing_trivial_pre_omega
   map 0 (mkEmpty as.size)
+termination_by map => as.size - i
 
 @[inline]
 def mapIdxM {α : Type u} {β : Type v} {m : Type v → Type w} [Monad m] (as : Array α) (f : Fin as.size → α → m β) : m (Array β) :=
@@ -379,13 +348,12 @@ def anyM {α : Type u} {m : Type → Type w} [Monad m] (p : α → m Bool) (as :
           loop (j+1)
       else
         pure false
-      termination_by stop - j
-      decreasing_by simp_wf; decreasing_trivial_pre_omega
     loop start
   if h : stop ≤ as.size then
     any stop h
   else
     any as.size (Nat.le_refl _)
+termination_by loop i j => stop - j
 
 @[inline]
 def allM {α : Type u} {m : Type → Type w} [Monad m] (p : α → m Bool) (as : Array α) (start := 0) (stop := as.size) : m Bool :=
@@ -433,10 +401,6 @@ def map {α : Type u} {β : Type v} (f : α → β) (as : Array α) : Array β :
 def mapIdx {α : Type u} {β : Type v} (as : Array α) (f : Fin as.size → α → β) : Array β :=
   Id.run <| as.mapIdxM f
 
-/-- Turns `#[a, b]` into `#[(a, 0), (b, 1)]`. -/
-def zipWithIndex (arr : Array α) : Array (α × Nat) :=
-  arr.mapIdx fun i a => (a, i)
-
 @[inline]
 def find? {α : Type} (as : Array α) (p : α → Bool) : Option α :=
   Id.run <| as.findM? p
@@ -461,13 +425,24 @@ def findRev? {α : Type} (as : Array α) (p : α → Bool) : Option α :=
 
 @[inline]
 def findIdx? {α : Type u} (as : Array α) (p : α → Bool) : Option Nat :=
-  let rec loop (j : Nat) :=
-    if h : j < as.size then
-      if p as[j] then some j else loop (j + 1)
-    else none
-    termination_by as.size - j
-    decreasing_by simp_wf; decreasing_trivial_pre_omega
-  loop 0
+  let rec loop (i : Nat) (j : Nat) (inv : i + j = as.size) : Option Nat :=
+    if hlt : j < as.size then
+      match i, inv with
+      | 0, inv => by
+        apply False.elim
+        rw [Nat.zero_add] at inv
+        rw [inv] at hlt
+        exact absurd hlt (Nat.lt_irrefl _)
+      | i+1, inv =>
+        if p as[j] then
+          some j
+        else
+          have : i + (j+1) = as.size := by
+            rw [← inv, Nat.add_comm j 1, Nat.add_assoc]
+          loop i (j+1) this
+    else
+      none
+  loop as.size 0 rfl
 
 def getIdx? [BEq α] (a : Array α) (v : α) : Option Nat :=
 a.findIdx? fun a => a == v
@@ -481,7 +456,7 @@ def all (as : Array α) (p : α → Bool) (start := 0) (stop := as.size) : Bool
   Id.run <| as.allM p start stop
 
 def contains [BEq α] (as : Array α) (a : α) : Bool :=
-  as.any (· == a)
+  as.any fun b => a == b
 
 def elem [BEq α] (a : α) (as : Array α) : Bool :=
   as.contains a
@@ -500,11 +475,6 @@ def elem [BEq α] (a : α) (as : Array α) : Bool :=
 def toList (as : Array α) : List α :=
   as.foldr List.cons []
 
-/-- Prepends an `Array α` onto the front of a list.  Equivalent to `as.toList ++ l`. -/
-@[inline]
-def toListAppend (as : Array α) (l : List α) : List α :=
-  as.foldr List.cons l
-
 instance {α : Type u} [Repr α] : Repr (Array α) where
   reprPrec a _ :=
     let _ : Std.ToFormat α := ⟨repr⟩
@@ -534,13 +504,6 @@ def concatMapM [Monad m] (f : α → m (Array β)) (as : Array α) : m (Array β
 def concatMap (f : α → Array β) (as : Array α) : Array β :=
   as.foldl (init := empty) fun bs a => bs ++ f a
 
-/-- Joins array of array into a single array.
-
-`flatten #[#[a₁, a₂, ⋯], #[b₁, b₂, ⋯], ⋯]` = `#[a₁, a₂, ⋯, b₁, b₂, ⋯]`
--/
-def flatten (as : Array (Array α)) : Array α :=
-  as.foldl (init := empty) fun r a => r ++ a
-
 end Array
 
 export Array (mkArray)
@@ -560,8 +523,7 @@ def isEqvAux (a b : Array α) (hsz : a.size = b.size) (p : α → α → Bool) (
      p a[i] b[i] && isEqvAux a b hsz p (i+1)
   else
     true
-termination_by a.size - i
-decreasing_by simp_wf; decreasing_trivial_pre_omega
+termination_by _ => a.size - i
 
 @[inline] def isEqv (a b : Array α) (p : α → α → Bool) : Bool :=
   if h : a.size = b.size then
@@ -665,8 +627,7 @@ def indexOfAux [BEq α] (a : Array α) (v : α) (i : Nat) : Option (Fin a.size)
     if a.get idx == v then some idx
     else indexOfAux a v (i+1)
   else none
-termination_by a.size - i
-decreasing_by simp_wf; decreasing_trivial_pre_omega
+termination_by _ => a.size - i
 
 def indexOf? [BEq α] (a : Array α) (v : α) : Option (Fin a.size) :=
   indexOfAux a v 0
@@ -698,7 +659,7 @@ where
       loop as (i+1) ⟨j-1, this⟩
     else
       as
-termination_by j - i
+termination_by _ => j - i
 
 def popWhile (p : α → Bool) (as : Array α) : Array α :=
   if h : as.size > 0 then
@@ -708,8 +669,7 @@ def popWhile (p : α → Bool) (as : Array α) : Array α :=
       as
   else
     as
-termination_by as.size
-decreasing_by simp_wf; decreasing_trivial_pre_omega
+termination_by popWhile as => as.size
 
 def takeWhile (p : α → Bool) (as : Array α) : Array α :=
   let rec go (i : Nat) (r : Array α) : Array α :=
@@ -721,39 +681,36 @@ def takeWhile (p : α → Bool) (as : Array α) : Array α :=
         r
     else
       r
-    termination_by as.size - i
-    decreasing_by simp_wf; decreasing_trivial_pre_omega
   go 0 #[]
+termination_by go i r => as.size - i
 
-/-- Remove the element at a given index from an array without bounds checks, using a `Fin` index.
-
-  This function takes worst case O(n) time because
-  it has to backshift all elements at positions greater than `i`.-/
-def feraseIdx (a : Array α) (i : Fin a.size) : Array α :=
-  if h : i.val + 1 < a.size then
-    let a' := a.swap ⟨i.val + 1, h⟩ i
-    let i' : Fin a'.size := ⟨i.val + 1, by simp [a', h]⟩
-    a'.feraseIdx i'
+def eraseIdxAux (i : Nat) (a : Array α) : Array α :=
+  if h : i < a.size then
+    let idx  : Fin a.size := ⟨i, h⟩;
+    let idx1 : Fin a.size := ⟨i - 1, by exact Nat.lt_of_le_of_lt (Nat.pred_le i) h⟩;
+    let a' := a.swap idx idx1
+    eraseIdxAux (i+1) a'
   else
     a.pop
-termination_by a.size - i.val
-decreasing_by simp_wf; exact Nat.sub_succ_lt_self _ _ i.isLt
+termination_by _ => a.size - i
 
-theorem size_feraseIdx (a : Array α) (i : Fin a.size) : (a.feraseIdx i).size = a.size - 1 := by
-  induction a, i using Array.feraseIdx.induct with
-  | @case1 a i h a' _ ih =>
-    unfold feraseIdx
-    simp [h, a', ih]
-  | case2 a i h =>
-    unfold feraseIdx
-    simp [h]
+def feraseIdx (a : Array α) (i : Fin a.size) : Array α :=
+  eraseIdxAux (i.val + 1) a
 
-/-- Remove the element at a given index from an array, or do nothing if the index is out of bounds.
-
-  This function takes worst case O(n) time because
-  it has to backshift all elements at positions greater than `i`.-/
 def eraseIdx (a : Array α) (i : Nat) : Array α :=
-  if h : i < a.size then a.feraseIdx ⟨i, h⟩ else a
+  if i < a.size then eraseIdxAux (i+1) a else a
+
+def eraseIdxSzAux (a : Array α) (i : Nat) (r : Array α) (heq : r.size = a.size) : { r : Array α // r.size = a.size - 1 } :=
+  if h : i < r.size then
+    let idx  : Fin r.size := ⟨i, h⟩;
+    let idx1 : Fin r.size := ⟨i - 1, by exact Nat.lt_of_le_of_lt (Nat.pred_le i) h⟩;
+    eraseIdxSzAux a (i+1) (r.swap idx idx1) ((size_swap r idx idx1).trans heq)
+  else
+    ⟨r.pop, (size_pop r).trans (heq ▸ rfl)⟩
+termination_by _ => r.size - i
+
+def eraseIdx' (a : Array α) (i : Fin a.size) : { r : Array α // r.size = a.size - 1 } :=
+  eraseIdxSzAux a (i.val + 1) a rfl
 
 def erase [BEq α] (as : Array α) (a : α) : Array α :=
   match as.indexOf? a with
@@ -769,11 +726,10 @@ def erase [BEq α] (as : Array α) (a : α) : Array α :=
       loop as ⟨j', by rw [size_swap]; exact j'.2⟩
     else
       as
-    termination_by j.1
-    decreasing_by simp_wf; decreasing_trivial_pre_omega
   let j := as.size
   let as := as.push a
   loop as ⟨j, size_push .. ▸ j.lt_succ_self⟩
+termination_by loop j => j.1
 
 /-- Insert element `a` at position `i`. Panics if `i` is not `i ≤ as.size`. -/
 def insertAt! (as : Array α) (i : Nat) (a : α) : Array α :=
@@ -791,11 +747,11 @@ def toArrayLit (a : Array α) (n : Nat) (hsz : a.size = n) : Array α :=
 theorem ext' {as bs : Array α} (h : as.data = bs.data) : as = bs := by
   cases as; cases bs; simp at h; rw [h]
 
-@[simp] theorem toArrayAux_eq (as : List α) (acc : Array α) : (as.toArrayAux acc).data = acc.data ++ as := by
+theorem toArrayAux_eq (as : List α) (acc : Array α) : (as.toArrayAux acc).data = acc.data ++ as := by
   induction as generalizing acc <;> simp [*, List.toArrayAux, Array.push, List.append_assoc, List.concat_eq_append]
 
 theorem data_toArray (as : List α) : as.toArray.data = as := by
-  simp [List.toArray, Array.mkEmpty]
+  simp [List.toArray, toArrayAux_eq, Array.mkEmpty]
 
 theorem toArrayLit_eq (as : Array α) (n : Nat) (hsz : as.size = n) : as = toArrayLit as n hsz := by
   apply ext'
@@ -810,7 +766,7 @@ where
     rfl
 
   go (i : Nat) (hi : i ≤ as.size) : toListLitAux as n hsz i hi (as.data.drop i) = as.data := by
-    induction i <;> simp [getLit_eq, List.get_drop_eq_drop, toListLitAux, List.drop, *]
+    cases i <;> simp [getLit_eq, List.get_drop_eq_drop, toListLitAux, List.drop, go]
 
 def isPrefixOfAux [BEq α] (as bs : Array α) (hle : as.size ≤ bs.size) (i : Nat) : Bool :=
   if h : i < as.size then
@@ -823,8 +779,7 @@ def isPrefixOfAux [BEq α] (as bs : Array α) (hle : as.size ≤ bs.size) (i : N
       false
   else
     true
-termination_by as.size - i
-decreasing_by simp_wf; decreasing_trivial_pre_omega
+termination_by _ => as.size - i
 
 /-- Return true iff `as` is a prefix of `bs`.
 That is, `bs = as ++ t` for some `t : List α`.-/
@@ -845,8 +800,7 @@ private def allDiffAux [BEq α] (as : Array α) (i : Nat) : Bool :=
     allDiffAuxAux as as[i] i h && allDiffAux as (i+1)
   else
     true
-termination_by as.size - i
-decreasing_by simp_wf; decreasing_trivial_pre_omega
+termination_by _ => as.size - i
 
 def allDiff [BEq α] (as : Array α) : Bool :=
   allDiffAux as 0
@@ -861,8 +815,7 @@ def allDiff [BEq α] (as : Array α) : Bool :=
       cs
   else
     cs
-termination_by as.size - i
-decreasing_by simp_wf; decreasing_trivial_pre_omega
+termination_by _ => as.size - i
 
 @[inline] def zipWith (as : Array α) (bs : Array β) (f : α → β → γ) : Array γ :=
   zipWithAux f as bs 0 #[]

src/Init/Data/Array/BasicAux.lean

@@ -9,7 +9,7 @@ import Init.Data.Nat.Linear
 import Init.NotationExtra
 
 theorem Array.of_push_eq_push {as bs : Array α} (h : as.push a = bs.push b) : as = bs ∧ a = b := by
-  simp only [push, mk.injEq] at h
+  simp [push] at h
   have ⟨h₁, h₂⟩ := List.of_concat_eq_concat h
   cases as; cases bs
   simp_all
@@ -47,8 +47,7 @@ where
       have hlt : i < as.size := Nat.lt_of_le_of_ne hle h
       let b ← f as[i]
       go (i+1) ⟨acc.val.push b, by simp [acc.property]⟩ hlt
-  termination_by as.size - i
-  decreasing_by decreasing_trivial_pre_omega
+termination_by go i _ _ => as.size - i
 
 @[inline] private unsafe def mapMonoMImp [Monad m] (as : Array α) (f : α → m α) : m (Array α) :=
   go 0 as

src/Init/Data/Array/DecidableEq.lean

@@ -5,7 +5,7 @@ Authors: Leonardo de Moura
 -/
 prelude
 import Init.Data.Array.Basic
-import Init.ByCases
+import Init.Classical
 
 namespace Array
 
@@ -20,26 +20,23 @@ theorem eq_of_isEqvAux [DecidableEq α] (a b : Array α) (hsz : a.size = b.size)
   · have heq : i = a.size := Nat.le_antisymm hi (Nat.ge_of_not_lt h)
     subst heq
     exact absurd (Nat.lt_of_lt_of_le high low) (Nat.lt_irrefl j)
-termination_by a.size - i
-decreasing_by decreasing_trivial_pre_omega
-
+termination_by _ => a.size - i
 
 theorem eq_of_isEqv [DecidableEq α] (a b : Array α) : Array.isEqv a b (fun x y => x = y) → a = b := by
   simp [Array.isEqv]
   split
-  next hsz =>
+  case inr => intro; contradiction
+  case inl hsz =>
    intro h
    have aux := eq_of_isEqvAux a b hsz 0 (Nat.zero_le ..) h
    exact ext a b hsz fun i h _ => aux i (Nat.zero_le ..) _
-  next => intro; contradiction
 
 theorem isEqvAux_self [DecidableEq α] (a : Array α) (i : Nat) : Array.isEqvAux a a rfl (fun x y => x = y) i = true := by
   unfold Array.isEqvAux
   split
-  next h => simp [h, isEqvAux_self a (i+1)]
-  next h => simp [h]
-termination_by a.size - i
-decreasing_by decreasing_trivial_pre_omega
+  case inl h => simp [h, isEqvAux_self a (i+1)]
+  case inr h => simp [h]
+termination_by _ => a.size - i
 
 theorem isEqv_self [DecidableEq α] (a : Array α) : Array.isEqv a a (fun x y => x = y) = true := by
   simp [isEqv, isEqvAux_self]

src/Init/Data/Array/Mem.lean

@@ -8,6 +8,16 @@ import Init.Data.Array.Basic
 import Init.Data.Nat.Linear
 import Init.Data.List.BasicAux
 
+theorem List.sizeOf_get_lt [SizeOf α] (as : List α) (i : Fin as.length) : sizeOf (as.get i) < sizeOf as := by
+  match as, i with
+  | [],    i      => apply Fin.elim0 i
+  | a::as, ⟨0, _⟩ => simp_arith [get]
+  | a::as, ⟨i+1, h⟩ =>
+    simp [get]
+    have h : i < as.length := Nat.lt_of_succ_lt_succ h
+    have ih := sizeOf_get_lt as ⟨i, h⟩
+    exact Nat.lt_of_lt_of_le ih (Nat.le_add_left ..)
+
 namespace Array
 
 /-- `a ∈ as` is a predicate which asserts that `a` is in the array `as`. -/
@@ -19,6 +29,10 @@ structure Mem (a : α) (as : Array α) : Prop where
 instance : Membership α (Array α) where
   mem a as := Mem a as
 
+theorem sizeOf_get_lt [SizeOf α] (as : Array α) (i : Fin as.size) : sizeOf (as.get i) < sizeOf as := by
+  cases as with | _ as =>
+  exact Nat.lt_trans (List.sizeOf_get_lt as i) (by simp_arith)
+
 theorem sizeOf_lt_of_mem [SizeOf α] {as : Array α} (h : a ∈ as) : sizeOf a < sizeOf as := by
   cases as with | _ as =>
   exact Nat.lt_trans (List.sizeOf_lt_of_mem h.val) (by simp_arith)
@@ -27,20 +41,13 @@ theorem sizeOf_lt_of_mem [SizeOf α] {as : Array α} (h : a ∈ as) : sizeOf a <
   cases as with | _ as =>
   exact Nat.lt_trans (List.sizeOf_get ..) (by simp_arith)
 
-@[simp] theorem sizeOf_getElem [SizeOf α] (as : Array α) (i : Nat) (h : i < as.size) :
-  sizeOf (as[i]'h) < sizeOf as := sizeOf_get _ _
-
 /-- This tactic, added to the `decreasing_trivial` toolbox, proves that
 `sizeOf arr[i] < sizeOf arr`, which is useful for well founded recursions
 over a nested inductive like `inductive T | mk : Array T → T`. -/
 macro "array_get_dec" : tactic =>
   `(tactic| first
-    -- subsumed by simp
-    -- | with_reducible apply sizeOf_get
-    -- | with_reducible apply sizeOf_getElem
-    | (with_reducible apply Nat.lt_trans (sizeOf_get ..)); simp_arith
-    | (with_reducible apply Nat.lt_trans (sizeOf_getElem ..)); simp_arith
-    )
+    | apply sizeOf_get
+    | apply Nat.lt_trans (sizeOf_get ..); simp_arith)
 
 macro_rules | `(tactic| decreasing_trivial) => `(tactic| array_get_dec)
 
@@ -50,10 +57,9 @@ provided that `a ∈ arr` which is useful for well founded recursions over a nes
 -- NB: This is analogue to tactic `sizeOf_list_dec`
 macro "array_mem_dec" : tactic =>
   `(tactic| first
-    | with_reducible apply Array.sizeOf_lt_of_mem; assumption; done
-    | with_reducible
-        apply Nat.lt_trans (Array.sizeOf_lt_of_mem ?h)
-        case' h => assumption
+    | apply Array.sizeOf_lt_of_mem; assumption; done
+    | apply Nat.lt_trans (Array.sizeOf_lt_of_mem ?h)
+      case' h => assumption
       simp_arith)
 
 macro_rules | `(tactic| decreasing_trivial) => `(tactic| array_mem_dec)

src/Init/Data/Array/QSort.lean

@@ -10,7 +10,7 @@ namespace Array
 -- TODO: remove the [Inhabited α] parameters as soon as we have the tactic framework for automating proof generation and using Array.fget
 
 def qpartition (as : Array α) (lt : α → α → Bool) (lo hi : Nat) : Nat × Array α :=
-  if h : as.size = 0 then (0, as) else have : Inhabited α := ⟨as[0]'(by revert h; cases as.size <;> simp)⟩ -- TODO: remove
+  if h : as.size = 0 then (0, as) else have : Inhabited α := ⟨as[0]'(by revert h; cases as.size <;> simp [Nat.zero_lt_succ])⟩ -- TODO: remove
   let mid := (lo + hi) / 2
   let as  := if lt (as.get! mid) (as.get! lo) then as.swap! lo mid else as
   let as  := if lt (as.get! hi)  (as.get! lo) then as.swap! lo hi  else as
@@ -26,9 +26,8 @@ def qpartition (as : Array α) (lt : α → α → Bool) (lo hi : Nat) : Nat ×
     else
       let as := as.swap! i hi
       (i, as)
-    termination_by hi - j
-    decreasing_by all_goals simp_wf; decreasing_trivial_pre_omega
   loop as lo lo
+termination_by _ => hi - j
 
 @[inline] partial def qsort (as : Array α) (lt : α → α → Bool) (low := 0) (high := as.size - 1) : Array α :=
   let rec @[specialize] sort (as : Array α) (low high : Nat) :=

src/Init/Data/Array/Subarray.lean

@@ -9,46 +9,29 @@ import Init.Data.Array.Basic
 universe u v w
 
 structure Subarray (α : Type u)  where
-  array : Array α
+  as : Array α
   start : Nat
   stop : Nat
-  start_le_stop : start ≤ stop
-  stop_le_array_size : stop ≤ array.size
-
-@[deprecated Subarray.array (since := "2024-04-13")]
-abbrev Subarray.as (s : Subarray α) : Array α := s.array
-
-@[deprecated Subarray.start_le_stop (since := "2024-04-13")]
-theorem Subarray.h₁ (s : Subarray α) : s.start ≤ s.stop := s.start_le_stop
-
-@[deprecated Subarray.stop_le_array_size (since := "2024-04-13")]
-theorem Subarray.h₂ (s : Subarray α) : s.stop ≤ s.array.size := s.stop_le_array_size
+  h₁ : start ≤ stop
+  h₂ : stop ≤ as.size
 
 namespace Subarray
 
 def size (s : Subarray α) : Nat :=
   s.stop - s.start
 
-theorem size_le_array_size {s : Subarray α} : s.size ≤ s.array.size := by
-  let {array, start, stop, start_le_stop, stop_le_array_size} := s
-  simp [size]
-  apply Nat.le_trans (Nat.sub_le stop start)
-  assumption
-
 def get (s : Subarray α) (i : Fin s.size) : α :=
-  have : s.start + i.val < s.array.size := by
-   apply Nat.lt_of_lt_of_le _ s.stop_le_array_size
+  have : s.start + i.val < s.as.size := by
+   apply Nat.lt_of_lt_of_le _ s.h₂
    have := i.isLt
    simp [size] at this
    rw [Nat.add_comm]
    exact Nat.add_lt_of_lt_sub this
-  s.array[s.start + i.val]
+  s.as[s.start + i.val]
 
 instance : GetElem (Subarray α) Nat α fun xs i => i < xs.size where
   getElem xs i h := xs.get ⟨i, h⟩
 
-instance : LawfulGetElem (Subarray α) Nat α fun xs i => i < xs.size where
-
 @[inline] def getD (s : Subarray α) (i : Nat) (v₀ : α) : α :=
   if h : i < s.size then s.get ⟨i, h⟩ else v₀
 
@@ -57,7 +40,7 @@ abbrev get! [Inhabited α] (s : Subarray α) (i : Nat) : α :=
 
 def popFront (s : Subarray α) : Subarray α :=
   if h : s.start < s.stop then
-    { s with start := s.start + 1, start_le_stop := Nat.le_of_lt_succ (Nat.add_lt_add_right h 1) }
+    { s with start := s.start + 1, h₁ := Nat.le_of_lt_succ (Nat.add_lt_add_right h 1) }
   else
     s
 
@@ -65,7 +48,7 @@ def popFront (s : Subarray α) : Subarray α :=
   let sz := USize.ofNat s.stop
   let rec @[specialize] loop (i : USize) (b : β) : m β := do
     if i < sz then
-      let a := s.array.uget i lcProof
+      let a := s.as.uget i lcProof
       match (← f a b) with
       | ForInStep.done  b => pure b
       | ForInStep.yield b => loop (i+1) b
@@ -83,27 +66,27 @@ instance : ForIn m (Subarray α) α where
 
 @[inline]
 def foldlM {α : Type u} {β : Type v} {m : Type v → Type w} [Monad m] (f : β → α → m β) (init : β) (as : Subarray α) : m β :=
-  as.array.foldlM f (init := init) (start := as.start) (stop := as.stop)
+  as.as.foldlM f (init := init) (start := as.start) (stop := as.stop)
 
 @[inline]
 def foldrM {α : Type u} {β : Type v} {m : Type v → Type w} [Monad m] (f : α → β → m β) (init : β) (as : Subarray α) : m β :=
-  as.array.foldrM f (init := init) (start := as.stop) (stop := as.start)
+  as.as.foldrM f (init := init) (start := as.stop) (stop := as.start)
 
 @[inline]
 def anyM {α : Type u} {m : Type → Type w} [Monad m] (p : α → m Bool) (as : Subarray α) : m Bool :=
-  as.array.anyM p (start := as.start) (stop := as.stop)
+  as.as.anyM p (start := as.start) (stop := as.stop)
 
 @[inline]
 def allM {α : Type u} {m : Type → Type w} [Monad m] (p : α → m Bool) (as : Subarray α) : m Bool :=
-  as.array.allM p (start := as.start) (stop := as.stop)
+  as.as.allM p (start := as.start) (stop := as.stop)
 
 @[inline]
 def forM {α : Type u} {m : Type v → Type w} [Monad m] (f : α → m PUnit) (as : Subarray α) : m PUnit :=
-  as.array.forM f (start := as.start) (stop := as.stop)
+  as.as.forM f (start := as.start) (stop := as.stop)
 
 @[inline]
 def forRevM {α : Type u} {m : Type v → Type w} [Monad m] (f : α → m PUnit) (as : Subarray α) : m PUnit :=
-  as.array.forRevM f (start := as.stop) (stop := as.start)
+  as.as.forRevM f (start := as.stop) (stop := as.start)
 
 @[inline]
 def foldl {α : Type u} {β : Type v} (f : β → α → β) (init : β) (as : Subarray α) : β :=
@@ -150,27 +133,16 @@ variable {α : Type u}
 
 def toSubarray (as : Array α) (start : Nat := 0) (stop : Nat := as.size) : Subarray α :=
   if h₂ : stop ≤ as.size then
-    if h₁ : start ≤ stop then
-      { array := as, start := start, stop := stop,
-        start_le_stop := h₁, stop_le_array_size := h₂ }
-    else
-      { array := as, start := stop, stop := stop,
-        start_le_stop := Nat.le_refl _, stop_le_array_size := h₂ }
+     if h₁ : start ≤ stop then
+       { as := as, start := start, stop := stop, h₁ := h₁, h₂ := h₂ }
+     else
+       { as := as, start := stop, stop := stop, h₁ := Nat.le_refl _, h₂ := h₂ }
   else
-    if h₁ : start ≤ as.size then
-      { array := as,
-        start := start,
-        stop := as.size,
-        start_le_stop := h₁,
-        stop_le_array_size := Nat.le_refl _ }
-    else
-      { array := as,
-        start := as.size,
-        stop := as.size,
-        start_le_stop := Nat.le_refl _,
-        stop_le_array_size := Nat.le_refl _ }
+     if h₁ : start ≤ as.size then
+       { as := as, start := start, stop := as.size, h₁ := h₁, h₂ := Nat.le_refl _ }
+     else
+       { as := as, start := as.size, stop := as.size, h₁ := Nat.le_refl _, h₂ := Nat.le_refl _ }
 
-@[coe]
 def ofSubarray (s : Subarray α) : Array α := Id.run do
   let mut as := mkEmpty (s.stop - s.start)
   for a in s do

src/Init/Data/Array/Subarray/Split.lean

@@ -1,71 +0,0 @@
-/-
-Copyright (c) 2024 Lean FRO, LLC. All rights reserved.
-Released under Apache 2.0 license as described in the file LICENSE.
-Authors: David Thrane Christiansen
--/
-
-prelude
-import Init.Data.Array.Basic
-import Init.Data.Array.Subarray
-import Init.Omega
-
-/-
-This module contains splitting operations on subarrays that crucially rely on `omega` for proof
-automation. Placing them in another module breaks an import cycle, because `omega` itself uses the
-array library.
--/
-
-namespace Subarray
-/--
-Splits a subarray into two parts.
--/
-def split (s : Subarray α) (i : Fin s.size.succ) : (Subarray α × Subarray α) :=
-  let ⟨i', isLt⟩ := i
-  have := s.start_le_stop
-  have := s.stop_le_array_size
-  have : i' ≤ s.stop - s.start := Nat.lt_succ.mp isLt
-  have : s.start + i' ≤ s.stop := by omega
-  have : s.start + i' ≤ s.array.size := by omega
-  have : s.start + i' ≤ s.stop := by
-    simp only [size] at isLt
-    omega
-  let pre := {s with
-    stop := s.start + i',
-    start_le_stop := by omega,
-    stop_le_array_size := by assumption
-  }
-  let post := {s with
-    start := s.start + i'
-    start_le_stop := by assumption
-  }
-  (pre, post)
-
-/--
-Removes the first `i` elements of the subarray. If there are `i` or fewer elements, the resulting
-subarray is empty.
--/
-def drop (arr : Subarray α) (i : Nat) : Subarray α where
-  array := arr.array
-  start := min (arr.start + i) arr.stop
-  stop := arr.stop
-  start_le_stop := by
-    rw [Nat.min_def]
-    split <;> simp only [Nat.le_refl, *]
-  stop_le_array_size := arr.stop_le_array_size
-
-/--
-Keeps only the first `i` elements of the subarray. If there are `i` or fewer elements, the resulting
-subarray is empty.
--/
-def take (arr : Subarray α) (i : Nat) : Subarray α where
-  array := arr.array
-  start := arr.start
-  stop := min (arr.start + i) arr.stop
-  start_le_stop := by
-    have := arr.start_le_stop
-    rw [Nat.min_def]
-    split <;> omega
-  stop_le_array_size := by
-    have := arr.stop_le_array_size
-    rw [Nat.min_def]
-    split <;> omega

src/Init/Data/BitVec.lean

@@ -1,10 +0,0 @@
-/-
-Copyright (c) 2024 Lean FRO, LLC. All rights reserved.
-Released under Apache 2.0 license as described in the file LICENSE.
-Authors: Scott Morrison
--/
-prelude
-import Init.Data.BitVec.Basic
-import Init.Data.BitVec.Bitblast
-import Init.Data.BitVec.Folds
-import Init.Data.BitVec.Lemmas