chore: basic functionality tests for modify/alter

.github/ISSUE_TEMPLATE/bug_report.md

@@ -39,7 +39,7 @@ Please put an X between the brackets as you perform the following steps:
 
 ### Versions
 
-[Output of `#version` or `#eval Lean.versionString`]
+[Output of `#eval Lean.versionString`]
 [OS version, if not using live.lean-lang.org.]
 
 ### Additional Information

.github/dependabot.yml

@@ -1,8 +0,0 @@
-version: 2
-updates:
-  - package-ecosystem: "github-actions"
-    directory: "/"
-    schedule:
-      interval: "monthly"
-    commit-message:
-      prefix: "chore: CI"

.github/workflows/actionlint.yml

@@ -17,6 +17,6 @@ jobs:
     - name: Checkout
       uses: actions/checkout@v4
     - name: actionlint
-      uses: raven-actions/actionlint@v2
+      uses: raven-actions/actionlint@v1
       with:
         pyflakes: false # we do not use python scripts

.github/workflows/ci.yml

@@ -217,7 +217,7 @@ jobs:
                 "release": true,
                 "check-level": 2,
                 "shell": "msys2 {0}",
-                "CMAKE_OPTIONS": "-G \"Unix Makefiles\"",
+                "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",
@@ -227,7 +227,7 @@ jobs:
               {
                 "name": "Linux aarch64",
                 "os": "nscloud-ubuntu-22.04-arm64-4x8",
-                "CMAKE_OPTIONS": "-DLEAN_INSTALL_SUFFIX=-linux_aarch64",
+                "CMAKE_OPTIONS": "-DUSE_GMP=OFF -DLEAN_INSTALL_SUFFIX=-linux_aarch64",
                 "release": true,
                 "check-level": 2,
                 "shell": "nix develop .#oldGlibcAArch -c bash -euxo pipefail {0}",
@@ -415,10 +415,6 @@ jobs:
       - name: Test
         id: test
         run: |
-          # give Linux debug unlimited stack, we're not interested in its specific stack usage
-          if [[ '${{ matrix.name }}' == 'Linux Debug' ]]; then
-            ulimit -s unlimited
-          fi
           time ctest --preset ${{ matrix.CMAKE_PRESET || 'release' }} --test-dir build/stage1 -j$NPROC --output-junit test-results.xml ${{ matrix.CTEST_OPTIONS }}
         if: (matrix.wasm || !matrix.cross) && needs.configure.outputs.check-level >= 1
       - name: Test Summary
@@ -496,7 +492,7 @@ jobs:
         with:
           path: artifacts
       - name: Release
-        uses: softprops/action-gh-release@v2
+        uses: softprops/action-gh-release@v1
         with:
           files: artifacts/*/*
           fail_on_unmatched_files: true
@@ -540,7 +536,7 @@ jobs:
           echo -e "\n*Full commit log*\n" >> diff.md
           git log --oneline "$last_tag"..HEAD | sed 's/^/* /' >> diff.md
       - name: Release Nightly
-        uses: softprops/action-gh-release@v2
+        uses: softprops/action-gh-release@v1
         with:
           body_path: diff.md
           prerelease: true

.github/workflows/nix-ci.yml

@@ -112,7 +112,7 @@ jobs:
         if: matrix.name == 'Nix Linux'
       - name: Check manual for broken links
         id: lychee
-        uses: lycheeverse/lychee-action@v2.0.2
+        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
@@ -129,7 +129,7 @@ jobs:
           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@v3.0
+        uses: nwtgck/actions-netlify@v2.0
         id: publish-manual
         with:
           publish-dir: ./dist

.github/workflows/pr-release.yml

@@ -34,7 +34,7 @@ jobs:
       - name: Download artifact from the previous workflow.
         if: ${{ steps.workflow-info.outputs.pullRequestNumber != '' }}
         id: download-artifact
-        uses: dawidd6/action-download-artifact@v6 # https://github.com/marketplace/actions/download-workflow-artifact
+        uses: dawidd6/action-download-artifact@v2 # https://github.com/marketplace/actions/download-workflow-artifact
         with:
           run_id: ${{ github.event.workflow_run.id }}
           path: artifacts
@@ -60,7 +60,7 @@ jobs:
           GH_TOKEN: ${{ secrets.PR_RELEASES_TOKEN }}
       - name: Release
         if: ${{ steps.workflow-info.outputs.pullRequestNumber != '' }}
-        uses: softprops/action-gh-release@v2
+        uses: softprops/action-gh-release@v1
         with:
           name: Release for PR ${{ steps.workflow-info.outputs.pullRequestNumber }}
           # There are coredumps files here as well, but all in deeper subdirectories.
@@ -75,7 +75,7 @@ jobs:
 
       - name: Report release status
         if: ${{ steps.workflow-info.outputs.pullRequestNumber != '' }}
-        uses: actions/github-script@v7
+        uses: actions/github-script@v6
         with:
           script: |
             await github.rest.repos.createCommitStatus({
@@ -111,7 +111,7 @@ jobs:
 
       - name: 'Setup jq'
         if: ${{ steps.workflow-info.outputs.pullRequestNumber != '' }}
-        uses: dcarbone/install-jq-action@v2.1.0
+        uses: dcarbone/install-jq-action@v1.0.1
 
       # Check that the most recently nightly coincides with 'git merge-base HEAD master'
       - name: Check merge-base and nightly-testing-YYYY-MM-DD
@@ -208,7 +208,7 @@ jobs:
 
       - name: Report mathlib base
         if: ${{ steps.workflow-info.outputs.pullRequestNumber != '' && steps.ready.outputs.mathlib_ready == 'true' }}
-        uses: actions/github-script@v7
+        uses: actions/github-script@v6
         with:
           script: |
             const description =

.github/workflows/stale.yml

@@ -11,7 +11,7 @@ jobs:
   stale:
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/stale@v9
+      - uses: actions/stale@v8
         with:
           days-before-stale: -1
           days-before-pr-stale: 30

RELEASES.md

@@ -8,329 +8,6 @@ This file contains work-in-progress notes for the upcoming release, as well as p
 Please check the [releases](https://github.com/leanprover/lean4/releases) page for the current status
 of each version.
 
-v4.15.0
-----------
-
-Development in progress.
-
-v4.14.0
-----------
-
-Release candidate, release notes will be copied from the branch `releases/v4.14.0` once completed.
-
-v4.13.0
-----------
-
-**Full Changelog**: https://github.com/leanprover/lean4/compare/v4.12.0...v4.13.0
-
-### Language features, tactics, and metaprograms
-
-* `structure` command
-  * [#5511](https://github.com/leanprover/lean4/pull/5511) allows structure parents to be type synonyms.
-  * [#5531](https://github.com/leanprover/lean4/pull/5531) allows default values for structure fields to be noncomputable.
-
-* `rfl` and `apply_rfl` tactics
-  * [#3714](https://github.com/leanprover/lean4/pull/3714), [#3718](https://github.com/leanprover/lean4/pull/3718) improve the `rfl` tactic and give better error messages.
-  * [#3772](https://github.com/leanprover/lean4/pull/3772) makes `rfl` no longer use kernel defeq for ground terms.
-  * [#5329](https://github.com/leanprover/lean4/pull/5329) tags `Iff.refl` with `@[refl]` (@Parcly-Taxel)
-  * [#5359](https://github.com/leanprover/lean4/pull/5359) ensures that the `rfl` tactic tries `Iff.rfl` (@Parcly-Taxel)
-
-* `unfold` tactic
-  * [#4834](https://github.com/leanprover/lean4/pull/4834) let `unfold` do zeta-delta reduction of local definitions, incorporating functionality of the Mathlib `unfold_let` tactic.
-
-* `omega` tactic
-  * [#5382](https://github.com/leanprover/lean4/pull/5382) fixes spurious error in [#5315](https://github.com/leanprover/lean4/issues/5315)
-  * [#5523](https://github.com/leanprover/lean4/pull/5523) supports `Int.toNat`
-
-* `simp` tactic
-  * [#5479](https://github.com/leanprover/lean4/pull/5479) lets `simp` apply rules with higher-order patterns.
-
-* `induction` tactic
-  * [#5494](https://github.com/leanprover/lean4/pull/5494) fixes `induction`’s "pre-tactic" block to always be indented, avoiding unintended uses of it.
-
-* `ac_nf` tactic
-  * [#5524](https://github.com/leanprover/lean4/pull/5524) adds `ac_nf`, a counterpart to `ac_rfl`, for normalizing expressions with respect to associativity and commutativity. Tests it with `BitVec` expressions.
-
-* `bv_decide`
-  * [#5211](https://github.com/leanprover/lean4/pull/5211) makes `extractLsb'` the primitive `bv_decide` understands, rather than `extractLsb` (@alexkeizer)
-  * [#5365](https://github.com/leanprover/lean4/pull/5365) adds `bv_decide` diagnoses.
-  * [#5375](https://github.com/leanprover/lean4/pull/5375) adds `bv_decide` normalization rules for `ofBool (a.getLsbD i)` and `ofBool a[i]` (@alexkeizer)
-  * [#5423](https://github.com/leanprover/lean4/pull/5423) enhances the rewriting rules of `bv_decide`
-  * [#5433](https://github.com/leanprover/lean4/pull/5433) presents the `bv_decide` counterexample at the API
-  * [#5484](https://github.com/leanprover/lean4/pull/5484) handles `BitVec.ofNat` with `Nat` fvars in `bv_decide`
-  * [#5506](https://github.com/leanprover/lean4/pull/5506), [#5507](https://github.com/leanprover/lean4/pull/5507) add `bv_normalize` rules.
-  * [#5568](https://github.com/leanprover/lean4/pull/5568) generalize the `bv_normalize` pipeline to support more general preprocessing passes
-  * [#5573](https://github.com/leanprover/lean4/pull/5573) gets `bv_normalize` up-to-date with the current `BitVec` rewrites
-  * Cleanups: [#5408](https://github.com/leanprover/lean4/pull/5408), [#5493](https://github.com/leanprover/lean4/pull/5493), [#5578](https://github.com/leanprover/lean4/pull/5578)
-
-
-* Elaboration improvements
-  * [#5266](https://github.com/leanprover/lean4/pull/5266) preserve order of overapplied arguments in `elab_as_elim` procedure.
-  * [#5510](https://github.com/leanprover/lean4/pull/5510) generalizes `elab_as_elim` to allow arbitrary motive applications.
-  * [#5283](https://github.com/leanprover/lean4/pull/5283), [#5512](https://github.com/leanprover/lean4/pull/5512) refine how named arguments suppress explicit arguments. Breaking change: some previously omitted explicit arguments may need explicit `_` arguments now.
-  * [#5376](https://github.com/leanprover/lean4/pull/5376) modifies projection instance binder info for instances, making parameters that are instance implicit in the type be implicit.
-  * [#5402](https://github.com/leanprover/lean4/pull/5402) localizes universe metavariable errors to `let` bindings and `fun` binders if possible. Makes "cannot synthesize metavariable" errors take precedence over unsolved universe level errors.
-  * [#5419](https://github.com/leanprover/lean4/pull/5419) must not reduce `ite` in the discriminant of `match`-expression when reducibility setting is `.reducible`
-  * [#5474](https://github.com/leanprover/lean4/pull/5474) have autoparams report parameter/field on failure
-  * [#5530](https://github.com/leanprover/lean4/pull/5530) makes automatic instance names about types with hygienic names be hygienic.
-
-* Deriving handlers
-  * [#5432](https://github.com/leanprover/lean4/pull/5432) makes `Repr` deriving instance handle explicit type parameters
-
-* Functional induction
-  * [#5364](https://github.com/leanprover/lean4/pull/5364) adds more equalities in context, more careful cleanup.
-
-* Linters
-  * [#5335](https://github.com/leanprover/lean4/pull/5335) fixes the unused variables linter complaining about match/tactic combinations
-  * [#5337](https://github.com/leanprover/lean4/pull/5337) fixes the unused variables linter complaining about some wildcard patterns
-
-* Other fixes
-  * [#4768](https://github.com/leanprover/lean4/pull/4768) fixes a parse error when `..` appears with a `.` on the next line
-
-* Metaprogramming
-  * [#3090](https://github.com/leanprover/lean4/pull/3090) handles level parameters in `Meta.evalExpr` (@eric-wieser)  
-  * [#5401](https://github.com/leanprover/lean4/pull/5401) instance for `Inhabited (TacticM α)` (@alexkeizer)
-  * [#5412](https://github.com/leanprover/lean4/pull/5412) expose Kernel.check for debugging purposes
-  * [#5556](https://github.com/leanprover/lean4/pull/5556) improves the "invalid projection" type inference error in `inferType`.
-  * [#5587](https://github.com/leanprover/lean4/pull/5587) allows `MVarId.assertHypotheses` to set `BinderInfo` and `LocalDeclKind`.
-  * [#5588](https://github.com/leanprover/lean4/pull/5588) adds `MVarId.tryClearMany'`, a variant of `MVarId.tryClearMany`.
-
-
-
-### Language server, widgets, and IDE extensions
-
-* [#5205](https://github.com/leanprover/lean4/pull/5205) decreases the latency of auto-completion in tactic blocks.
-* [#5237](https://github.com/leanprover/lean4/pull/5237) fixes symbol occurrence highlighting in VS Code not highlighting occurrences when moving the text cursor into the identifier from the right.
-* [#5257](https://github.com/leanprover/lean4/pull/5257) fixes several instances of incorrect auto-completions being reported.
-* [#5299](https://github.com/leanprover/lean4/pull/5299) allows auto-completion to report completions for global identifiers when the elaborator fails to provide context-specific auto-completions.
-* [#5312](https://github.com/leanprover/lean4/pull/5312) fixes the server breaking when changing whitespace after the module header.
-* [#5322](https://github.com/leanprover/lean4/pull/5322) fixes several instances of auto-completion reporting non-existent namespaces.
-* [#5428](https://github.com/leanprover/lean4/pull/5428) makes sure to always report some recent file range as progress when waiting for elaboration.
-
-
-### Pretty printing
-
-* [#4979](https://github.com/leanprover/lean4/pull/4979) make pretty printer escape identifiers that are tokens.
-* [#5389](https://github.com/leanprover/lean4/pull/5389) makes formatter use the current token table.
-* [#5513](https://github.com/leanprover/lean4/pull/5513) use breakable instead of unbreakable whitespace when formatting tokens.
-
-
-### Library
-
-* [#5222](https://github.com/leanprover/lean4/pull/5222) reduces allocations in `Json.compress`.
-* [#5231](https://github.com/leanprover/lean4/pull/5231) upstreams `Zero` and `NeZero`
-* [#5292](https://github.com/leanprover/lean4/pull/5292) refactors `Lean.Elab.Deriving.FromToJson` (@arthur-adjedj)
-* [#5415](https://github.com/leanprover/lean4/pull/5415) implements `Repr Empty` (@TomasPuverle)
-* [#5421](https://github.com/leanprover/lean4/pull/5421) implements `To/FromJSON Empty` (@TomasPuverle)
-
-* Logic
-  * [#5263](https://github.com/leanprover/lean4/pull/5263) allows simplifying `dite_not`/`decide_not` with only `Decidable (¬p)`.
-  * [#5268](https://github.com/leanprover/lean4/pull/5268) fixes binders on `ite_eq_left_iff`
-  * [#5284](https://github.com/leanprover/lean4/pull/5284) turns off `Inhabited (Sum α β)` instances
-  * [#5355](https://github.com/leanprover/lean4/pull/5355) adds simp lemmas for `LawfulBEq`
-  * [#5374](https://github.com/leanprover/lean4/pull/5374) add `Nonempty` instances for products, allowing more `partial` functions to elaborate successfully
-  * [#5447](https://github.com/leanprover/lean4/pull/5447) updates Pi instance names
-  * [#5454](https://github.com/leanprover/lean4/pull/5454) makes some instance arguments implicit
-  * [#5456](https://github.com/leanprover/lean4/pull/5456) adds `heq_comm`
-  * [#5529](https://github.com/leanprover/lean4/pull/5529) moves `@[simp]` from `exists_prop'` to `exists_prop`
-
-* `Bool`
-  * [#5228](https://github.com/leanprover/lean4/pull/5228) fills gaps in Bool lemmas
-  * [#5332](https://github.com/leanprover/lean4/pull/5332) adds notation `^^` for Bool.xor
-  * [#5351](https://github.com/leanprover/lean4/pull/5351) removes `_root_.and` (and or/not/xor) and instead exports/uses `Bool.and` (etc.).
-
-* `BitVec`
-  * [#5240](https://github.com/leanprover/lean4/pull/5240) removes BitVec simps with complicated RHS
-  * [#5247](https://github.com/leanprover/lean4/pull/5247) `BitVec.getElem_zeroExtend`
-  * [#5248](https://github.com/leanprover/lean4/pull/5248) simp lemmas for BitVec, improving confluence
-  * [#5249](https://github.com/leanprover/lean4/pull/5249) removes `@[simp]` from some BitVec lemmas
-  * [#5252](https://github.com/leanprover/lean4/pull/5252) changes `BitVec.intMin/Max` from abbrev to def
-  * [#5278](https://github.com/leanprover/lean4/pull/5278) adds `BitVec.getElem_truncate` (@tobiasgrosser)
-  * [#5281](https://github.com/leanprover/lean4/pull/5281) adds udiv/umod bitblasting for `bv_decide` (@bollu)
-  * [#5297](https://github.com/leanprover/lean4/pull/5297) `BitVec` unsigned order theoretic results
-  * [#5313](https://github.com/leanprover/lean4/pull/5313) adds more basic BitVec ordering theory for UInt
-  * [#5314](https://github.com/leanprover/lean4/pull/5314) adds `toNat_sub_of_le` (@bollu)
-  * [#5357](https://github.com/leanprover/lean4/pull/5357) adds `BitVec.truncate` lemmas
-  * [#5358](https://github.com/leanprover/lean4/pull/5358) introduces `BitVec.setWidth` to unify zeroExtend and truncate (@tobiasgrosser)
-  * [#5361](https://github.com/leanprover/lean4/pull/5361) some BitVec GetElem lemmas
-  * [#5385](https://github.com/leanprover/lean4/pull/5385) adds `BitVec.ofBool_[and|or|xor]_ofBool` theorems (@tobiasgrosser)
-  * [#5404](https://github.com/leanprover/lean4/pull/5404) more of `BitVec.getElem_*` (@tobiasgrosser)
-  * [#5410](https://github.com/leanprover/lean4/pull/5410) BitVec analogues of `Nat.{mul_two, two_mul, mul_succ, succ_mul}` (@bollu)
-  * [#5411](https://github.com/leanprover/lean4/pull/5411) `BitVec.toNat_{add,sub,mul_of_lt}` for BitVector non-overflow reasoning (@bollu)
-  * [#5413](https://github.com/leanprover/lean4/pull/5413) adds `_self`, `_zero`, and `_allOnes` for `BitVec.[and|or|xor]` (@tobiasgrosser)
-  * [#5416](https://github.com/leanprover/lean4/pull/5416) adds LawCommIdentity + IdempotentOp for `BitVec.[and|or|xor]` (@tobiasgrosser)
-  * [#5418](https://github.com/leanprover/lean4/pull/5418) decidable quantifers for BitVec
-  * [#5450](https://github.com/leanprover/lean4/pull/5450) adds `BitVec.toInt_[intMin|neg|neg_of_ne_intMin]` (@tobiasgrosser)
-  * [#5459](https://github.com/leanprover/lean4/pull/5459) missing BitVec lemmas
-  * [#5469](https://github.com/leanprover/lean4/pull/5469) adds `BitVec.[not_not, allOnes_shiftLeft_or_shiftLeft, allOnes_shiftLeft_and_shiftLeft]` (@luisacicolini)
-  * [#5478](https://github.com/leanprover/lean4/pull/5478) adds `BitVec.(shiftLeft_add_distrib, shiftLeft_ushiftRight)` (@luisacicolini)
-  * [#5487](https://github.com/leanprover/lean4/pull/5487) adds `sdiv_eq`, `smod_eq` to allow `sdiv`/`smod` bitblasting (@bollu)
-  * [#5491](https://github.com/leanprover/lean4/pull/5491) adds `BitVec.toNat_[abs|sdiv|smod]` (@tobiasgrosser)
-  * [#5492](https://github.com/leanprover/lean4/pull/5492) `BitVec.(not_sshiftRight, not_sshiftRight_not, getMsb_not, msb_not)` (@luisacicolini)
-  * [#5499](https://github.com/leanprover/lean4/pull/5499) `BitVec.Lemmas` - drop non-terminal simps (@tobiasgrosser)
-  * [#5505](https://github.com/leanprover/lean4/pull/5505) unsimps `BitVec.divRec_succ'`
-  * [#5508](https://github.com/leanprover/lean4/pull/5508) adds `BitVec.getElem_[add|add_add_bool|mul|rotateLeft|rotateRight…` (@tobiasgrosser)
-  * [#5554](https://github.com/leanprover/lean4/pull/5554) adds `Bitvec.[add, sub, mul]_eq_xor` and `width_one_cases` (@luisacicolini)
-
-* `List`
-  * [#5242](https://github.com/leanprover/lean4/pull/5242) improve naming for `List.mergeSort` lemmas
-  * [#5302](https://github.com/leanprover/lean4/pull/5302) provide `mergeSort` comparator autoParam
-  * [#5373](https://github.com/leanprover/lean4/pull/5373) fix name of `List.length_mergeSort`
-  * [#5377](https://github.com/leanprover/lean4/pull/5377) upstream `map_mergeSort`
-  * [#5378](https://github.com/leanprover/lean4/pull/5378) modify signature of lemmas about `mergeSort`
-  * [#5245](https://github.com/leanprover/lean4/pull/5245) avoid importing `List.Basic` without List.Impl
-  * [#5260](https://github.com/leanprover/lean4/pull/5260) review of List API
-  * [#5264](https://github.com/leanprover/lean4/pull/5264) review of List API
-  * [#5269](https://github.com/leanprover/lean4/pull/5269) remove HashMap's duplicated Pairwise and Sublist
-  * [#5271](https://github.com/leanprover/lean4/pull/5271) remove @[simp] from `List.head_mem` and similar
-  * [#5273](https://github.com/leanprover/lean4/pull/5273) lemmas about `List.attach`
-  * [#5275](https://github.com/leanprover/lean4/pull/5275) reverse direction of `List.tail_map`
-  * [#5277](https://github.com/leanprover/lean4/pull/5277) more `List.attach` lemmas
-  * [#5285](https://github.com/leanprover/lean4/pull/5285) `List.count` lemmas
-  * [#5287](https://github.com/leanprover/lean4/pull/5287) use boolean predicates in `List.filter`
-  * [#5289](https://github.com/leanprover/lean4/pull/5289) `List.mem_ite_nil_left` and analogues
-  * [#5293](https://github.com/leanprover/lean4/pull/5293) cleanup of `List.findIdx` / `List.take` lemmas
-  * [#5294](https://github.com/leanprover/lean4/pull/5294) switch primes on `List.getElem_take`
-  * [#5300](https://github.com/leanprover/lean4/pull/5300) more `List.findIdx` theorems
-  * [#5310](https://github.com/leanprover/lean4/pull/5310) fix `List.all/any` lemmas
-  * [#5311](https://github.com/leanprover/lean4/pull/5311) fix `List.countP` lemmas
-  * [#5316](https://github.com/leanprover/lean4/pull/5316) `List.tail` lemma
-  * [#5331](https://github.com/leanprover/lean4/pull/5331) fix implicitness of `List.getElem_mem`
-  * [#5350](https://github.com/leanprover/lean4/pull/5350) `List.replicate` lemmas
-  * [#5352](https://github.com/leanprover/lean4/pull/5352) `List.attachWith` lemmas
-  * [#5353](https://github.com/leanprover/lean4/pull/5353) `List.head_mem_head?`
-  * [#5360](https://github.com/leanprover/lean4/pull/5360) lemmas about `List.tail`
-  * [#5391](https://github.com/leanprover/lean4/pull/5391) review of `List.erase` / `List.find` lemmas
-  * [#5392](https://github.com/leanprover/lean4/pull/5392) `List.fold` / `attach` lemmas
-  * [#5393](https://github.com/leanprover/lean4/pull/5393) `List.fold` relators
-  * [#5394](https://github.com/leanprover/lean4/pull/5394) lemmas about `List.maximum?`
-  * [#5403](https://github.com/leanprover/lean4/pull/5403) theorems about `List.toArray`
-  * [#5405](https://github.com/leanprover/lean4/pull/5405) reverse direction of `List.set_map`
-  * [#5448](https://github.com/leanprover/lean4/pull/5448) add lemmas about `List.IsPrefix` (@Command-Master)
-  * [#5460](https://github.com/leanprover/lean4/pull/5460) missing `List.set_replicate_self`
-  * [#5518](https://github.com/leanprover/lean4/pull/5518) rename `List.maximum?` to `max?`
-  * [#5519](https://github.com/leanprover/lean4/pull/5519) upstream `List.fold` lemmas
-  * [#5520](https://github.com/leanprover/lean4/pull/5520) restore `@[simp]` on `List.getElem_mem` etc.
-  * [#5521](https://github.com/leanprover/lean4/pull/5521) List simp fixes
-  * [#5550](https://github.com/leanprover/lean4/pull/5550) `List.unattach` and simp lemmas
-  * [#5594](https://github.com/leanprover/lean4/pull/5594) induction-friendly `List.min?_cons`
-
-* `Array`
-  * [#5246](https://github.com/leanprover/lean4/pull/5246) cleanup imports of Array.Lemmas
-  * [#5255](https://github.com/leanprover/lean4/pull/5255) split Init.Data.Array.Lemmas for better bootstrapping
-  * [#5288](https://github.com/leanprover/lean4/pull/5288) rename `Array.data` to `Array.toList`
-  * [#5303](https://github.com/leanprover/lean4/pull/5303) cleanup of `List.getElem_append` variants
-  * [#5304](https://github.com/leanprover/lean4/pull/5304) `Array.not_mem_empty`
-  * [#5400](https://github.com/leanprover/lean4/pull/5400) reorganization in Array/Basic
-  * [#5420](https://github.com/leanprover/lean4/pull/5420) make `Array` functions either semireducible or use structural recursion
-  * [#5422](https://github.com/leanprover/lean4/pull/5422) refactor `DecidableEq (Array α)`
-  * [#5452](https://github.com/leanprover/lean4/pull/5452) refactor of Array
-  * [#5458](https://github.com/leanprover/lean4/pull/5458) cleanup of Array docstrings after refactor
-  * [#5461](https://github.com/leanprover/lean4/pull/5461) restore `@[simp]` on `Array.swapAt!_def`
-  * [#5465](https://github.com/leanprover/lean4/pull/5465) improve Array GetElem lemmas
-  * [#5466](https://github.com/leanprover/lean4/pull/5466) `Array.foldX` lemmas
-  * [#5472](https://github.com/leanprover/lean4/pull/5472) @[simp] lemmas about `List.toArray`
-  * [#5485](https://github.com/leanprover/lean4/pull/5485) reverse simp direction for `toArray_concat`
-  * [#5514](https://github.com/leanprover/lean4/pull/5514) `Array.eraseReps`
-  * [#5515](https://github.com/leanprover/lean4/pull/5515) upstream `Array.qsortOrd`
-  * [#5516](https://github.com/leanprover/lean4/pull/5516) upstream `Subarray.empty`
-  * [#5526](https://github.com/leanprover/lean4/pull/5526) fix name of `Array.length_toList`
-  * [#5527](https://github.com/leanprover/lean4/pull/5527) reduce use of deprecated lemmas in Array
-  * [#5534](https://github.com/leanprover/lean4/pull/5534) cleanup of Array GetElem lemmas
-  * [#5536](https://github.com/leanprover/lean4/pull/5536) fix `Array.modify` lemmas
-  * [#5551](https://github.com/leanprover/lean4/pull/5551) upstream `Array.flatten` lemmas
-  * [#5552](https://github.com/leanprover/lean4/pull/5552) switch obvious cases of array "bang"`[]!` indexing to rely on hypothesis (@TomasPuverle)
-  * [#5577](https://github.com/leanprover/lean4/pull/5577) add missing simp to `Array.size_feraseIdx`
-  * [#5586](https://github.com/leanprover/lean4/pull/5586) `Array/Option.unattach`
-
-* `Option`
-  * [#5272](https://github.com/leanprover/lean4/pull/5272) remove @[simp] from `Option.pmap/pbind` and add simp lemmas
-  * [#5307](https://github.com/leanprover/lean4/pull/5307) restoring Option simp confluence
-  * [#5354](https://github.com/leanprover/lean4/pull/5354) remove @[simp] from `Option.bind_map`
-  * [#5532](https://github.com/leanprover/lean4/pull/5532) `Option.attach`
-  * [#5539](https://github.com/leanprover/lean4/pull/5539) fix explicitness of `Option.mem_toList`
-
-* `Nat`
-  * [#5241](https://github.com/leanprover/lean4/pull/5241) add @[simp] to `Nat.add_eq_zero_iff`
-  * [#5261](https://github.com/leanprover/lean4/pull/5261) Nat bitwise lemmas
-  * [#5262](https://github.com/leanprover/lean4/pull/5262) `Nat.testBit_add_one` should not be a global simp lemma
-  * [#5267](https://github.com/leanprover/lean4/pull/5267) protect some Nat bitwise theorems
-  * [#5305](https://github.com/leanprover/lean4/pull/5305) rename Nat bitwise lemmas
-  * [#5306](https://github.com/leanprover/lean4/pull/5306) add `Nat.self_sub_mod` lemma
-  * [#5503](https://github.com/leanprover/lean4/pull/5503) restore @[simp] to upstreamed `Nat.lt_off_iff`
-
-* `Int`
-  * [#5301](https://github.com/leanprover/lean4/pull/5301) rename `Int.div/mod` to `Int.tdiv/tmod`
-  * [#5320](https://github.com/leanprover/lean4/pull/5320) add `ediv_nonneg_of_nonpos_of_nonpos` to DivModLemmas (@sakehl)
-
-* `Fin`
-  * [#5250](https://github.com/leanprover/lean4/pull/5250) missing lemma about `Fin.ofNat'`
-  * [#5356](https://github.com/leanprover/lean4/pull/5356) `Fin.ofNat'` uses `NeZero`
-  * [#5379](https://github.com/leanprover/lean4/pull/5379) remove some @[simp]s from Fin lemmas
-  * [#5380](https://github.com/leanprover/lean4/pull/5380) missing Fin @[simp] lemmas
-
-* `HashMap`
-  * [#5244](https://github.com/leanprover/lean4/pull/5244) (`DHashMap`|`HashMap`|`HashSet`).(`getKey?`|`getKey`|`getKey!`|`getKeyD`)
-  * [#5362](https://github.com/leanprover/lean4/pull/5362) remove the last use of `Lean.(HashSet|HashMap)`
-  * [#5369](https://github.com/leanprover/lean4/pull/5369) `HashSet.ofArray`
-  * [#5370](https://github.com/leanprover/lean4/pull/5370) `HashSet.partition`
-  * [#5581](https://github.com/leanprover/lean4/pull/5581) `Singleton`/`Insert`/`Union` instances for `HashMap`/`Set`
-  * [#5582](https://github.com/leanprover/lean4/pull/5582) `HashSet.all`/`any`
-  * [#5590](https://github.com/leanprover/lean4/pull/5590) adding `Insert`/`Singleton`/`Union` instances for `HashMap`/`Set.Raw`
-  * [#5591](https://github.com/leanprover/lean4/pull/5591) `HashSet.Raw.all/any`
-
-* `Monads`
-  * [#5463](https://github.com/leanprover/lean4/pull/5463) upstream some monad lemmas
-  * [#5464](https://github.com/leanprover/lean4/pull/5464) adjust simp attributes on monad lemmas
-  * [#5522](https://github.com/leanprover/lean4/pull/5522) more monadic simp lemmas
-
-* Simp lemma cleanup
-  * [#5251](https://github.com/leanprover/lean4/pull/5251) remove redundant simp annotations
-  * [#5253](https://github.com/leanprover/lean4/pull/5253) remove Int simp lemmas that can't fire
-  * [#5254](https://github.com/leanprover/lean4/pull/5254) variables appearing on both sides of an iff should be implicit
-  * [#5381](https://github.com/leanprover/lean4/pull/5381) cleaning up redundant simp lemmas
-
-
-### Compiler, runtime, and FFI
-
-* [#4685](https://github.com/leanprover/lean4/pull/4685) fixes a typo in the C `run_new_frontend` signature
-* [#4729](https://github.com/leanprover/lean4/pull/4729) has IR checker suggest using `noncomputable`
-* [#5143](https://github.com/leanprover/lean4/pull/5143) adds a shared library for Lake
-* [#5437](https://github.com/leanprover/lean4/pull/5437) removes (syntactically) duplicate imports (@euprunin)
-* [#5462](https://github.com/leanprover/lean4/pull/5462) updates `src/lake/lakefile.toml` to the adjusted Lake build process
-* [#5541](https://github.com/leanprover/lean4/pull/5541) removes new shared libs before build to better support Windows
-* [#5558](https://github.com/leanprover/lean4/pull/5558) make `lean.h` compile with MSVC (@kant2002)
-* [#5564](https://github.com/leanprover/lean4/pull/5564) removes non-conforming size-0 arrays (@eric-wieser)
-
-
-### Lake
-  * Reservoir build cache. Lake will now attempt to fetch a pre-built copy of the package from Reservoir before building it. This is only enabled for packages in the leanprover or leanprover-community organizations on versions indexed by Reservoir. Users can force Lake to build packages from the source by passing --no-cache on the CLI or by setting the  LAKE_NO_CACHE environment variable to true. [#5486](https://github.com/leanprover/lean4/pull/5486), [#5572](https://github.com/leanprover/lean4/pull/5572), [#5583](https://github.com/leanprover/lean4/pull/5583), [#5600](https://github.com/leanprover/lean4/pull/5600), [#5641](https://github.com/leanprover/lean4/pull/5641), [#5642](https://github.com/leanprover/lean4/pull/5642).
-  * [#5504](https://github.com/leanprover/lean4/pull/5504) lake new and lake init now produce TOML configurations by default.
-  * [#5878](https://github.com/leanprover/lean4/pull/5878) fixes a serious issue where Lake would delete path dependencies when attempting to cleanup a dependency required with an incorrect name.
-
-  * **Breaking changes**
-    * [#5641](https://github.com/leanprover/lean4/pull/5641) A Lake build of target within a package will no longer build a package's dependencies package-level extra target dependencies. At the technical level, a package's extraDep facet no longer transitively builds its dependencies’ extraDep facets (which include their extraDepTargets).
-
-### Documentation fixes
-
-* [#3918](https://github.com/leanprover/lean4/pull/3918) `@[builtin_doc]` attribute (@digama0)
-* [#4305](https://github.com/leanprover/lean4/pull/4305) explains the borrow syntax (@eric-wieser)
-* [#5349](https://github.com/leanprover/lean4/pull/5349) adds documentation for `groupBy.loop` (@vihdzp)
-* [#5473](https://github.com/leanprover/lean4/pull/5473) fixes typo in `BitVec.mul` docstring (@llllvvuu)
-* [#5476](https://github.com/leanprover/lean4/pull/5476) fixes typos in `Lean.MetavarContext`
-* [#5481](https://github.com/leanprover/lean4/pull/5481) removes mention of `Lean.withSeconds` (@alexkeizer)
-* [#5497](https://github.com/leanprover/lean4/pull/5497) updates documentation and tests for `toUIntX` functions (@TomasPuverle)
-* [#5087](https://github.com/leanprover/lean4/pull/5087) mentions that `inferType` does not ensure type correctness
-* Many fixes to spelling across the doc-strings, (@euprunin): [#5425](https://github.com/leanprover/lean4/pull/5425) [#5426](https://github.com/leanprover/lean4/pull/5426) [#5427](https://github.com/leanprover/lean4/pull/5427) [#5430](https://github.com/leanprover/lean4/pull/5430)  [#5431](https://github.com/leanprover/lean4/pull/5431) [#5434](https://github.com/leanprover/lean4/pull/5434) [#5435](https://github.com/leanprover/lean4/pull/5435) [#5436](https://github.com/leanprover/lean4/pull/5436) [#5438](https://github.com/leanprover/lean4/pull/5438) [#5439](https://github.com/leanprover/lean4/pull/5439) [#5440](https://github.com/leanprover/lean4/pull/5440) [#5599](https://github.com/leanprover/lean4/pull/5599)
-
-### Changes to CI
-
-* [#5343](https://github.com/leanprover/lean4/pull/5343) allows addition of `release-ci` label via comment (@thorimur)
-* [#5344](https://github.com/leanprover/lean4/pull/5344) sets check level correctly during workflow (@thorimur)
-* [#5444](https://github.com/leanprover/lean4/pull/5444) Mathlib's `lean-pr-testing-NNNN` branches should use Batteries' `lean-pr-testing-NNNN` branches
-* [#5489](https://github.com/leanprover/lean4/pull/5489) commit `lake-manifest.json` when updating `lean-pr-testing` branches
-* [#5490](https://github.com/leanprover/lean4/pull/5490) use separate secrets for commenting and branching in `pr-release.yml`
-
 v4.12.0
 ----------
 

doc/make/index.md

@@ -1,6 +1,6 @@
-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](../dev/index.md).
+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](../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.
+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
 ------------

flake.nix

@@ -38,11 +38,7 @@
           # more convenient `ctest` output
           CTEST_OUTPUT_ON_FAILURE = 1;
         } // pkgs.lib.optionalAttrs pkgs.stdenv.isLinux {
-          GMP = (pkgsDist.gmp.override { withStatic = true; }).overrideAttrs (attrs:
-            pkgs.lib.optionalAttrs (pkgs.stdenv.system == "aarch64-linux") {
-              # would need additional linking setup on Linux aarch64, we don't use it anywhere else either
-              hardeningDisable = [ "stackprotector" ];
-            });
+          GMP = pkgsDist.gmp.override { withStatic = true; };
           LIBUV = pkgsDist.libuv.overrideAttrs (attrs: {
             configureFlags = ["--enable-static"];
             hardeningDisable = [ "stackprotector" ];

script/prepare-llvm-linux.sh

@@ -64,7 +64,7 @@ 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 ROOT/lib/glibc/libpthread_nonshared.a -Wl,--as-needed -Wl,-Bstatic -lgmp -lunwind -luv -Wl,-Bdynamic -Wl,--no-as-needed -fuse-ld=lld'"
+echo -n " -DLEANC_INTERNAL_LINKER_FLAGS='-L ROOT/lib -L ROOT/lib/glibc ROOT/lib/glibc/libc_nonshared.a ROOT/lib/glibc/libpthread_nonshared.a -Wl,--as-needed -Wl,-Bstatic -lgmp -lunwind -luv -lpthread -ldl -lrt -Wl,-Bdynamic -Wl,--no-as-needed -fuse-ld=lld'"
 # when not using the above flags, link GMP dynamically/as usual
 echo -n " -DLEAN_EXTRA_LINKER_FLAGS='-Wl,--as-needed -lgmp -luv -lpthread -ldl -lrt -Wl,--no-as-needed'"
 # do not set `LEAN_CC` for tests

src/CMakeLists.txt

@@ -10,7 +10,7 @@ endif()
 include(ExternalProject)
 project(LEAN CXX C)
 set(LEAN_VERSION_MAJOR 4)
-set(LEAN_VERSION_MINOR 15)
+set(LEAN_VERSION_MINOR 12)
 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'")

src/Init/Control/Basic.lean

@@ -11,13 +11,8 @@ universe u v w
 /--
 A `ForIn'` instance, which handles `for h : x in c do`,
 can also handle `for x in x do` by ignoring `h`, and so provides a `ForIn` instance.
-
-Note that this instance will cause a potentially non-defeq duplication if both `ForIn` and `ForIn'`
-instances are provided for the same type.
 -/
--- We set the priority to 500 so it is below the default,
--- but still above the low priority instance from `Stream`.
-instance (priority := 500) instForInOfForIn' [ForIn' m ρ α d] : ForIn m ρ α where
+instance (priority := low) instForInOfForIn' [ForIn' m ρ α d] : ForIn m ρ α where
   forIn x b f := forIn' x b fun a _ => f a
 
 @[simp] theorem forIn'_eq_forIn [d : Membership α ρ] [ForIn' m ρ α d] {β} [Monad m] (x : ρ) (b : β)
@@ -35,15 +30,6 @@ instance (priority := 500) instForInOfForIn' [ForIn' m ρ α d] : ForIn m ρ α
   simp [h]
   rfl
 
-/-- Extract the value from a `ForInStep`, ignoring whether it is `done` or `yield`. -/
-def ForInStep.value (x : ForInStep α) : α :=
-  match x with
-  | ForInStep.done b => b
-  | ForInStep.yield b => b
-
-@[simp] theorem ForInStep.value_done (b : β) : (ForInStep.done b).value = b := rfl
-@[simp] theorem ForInStep.value_yield (b : β) : (ForInStep.yield b).value = b := rfl
-
 @[reducible]
 def Functor.mapRev {f : Type u → Type v} [Functor f] {α β : Type u} : f α → (α → β) → f β :=
   fun a f => f <$> a

src/Init/Conv.lean

@@ -7,7 +7,6 @@ Notation for operators defined at Prelude.lean
 -/
 prelude
 import Init.Tactics
-import Init.Meta
 
 namespace Lean.Parser.Tactic.Conv
 
@@ -47,20 +46,12 @@ scoped syntax (name := withAnnotateState)
 /-- `skip` does nothing. -/
 syntax (name := skip) "skip" : conv
 
-/--
-Traverses into the left subterm of a binary operator.
-
-In general, for an `n`-ary operator, it traverses into the second to last argument.
-It is a synonym for `arg -2`.
--/
+/-- Traverses into the left subterm of a binary operator.
+(In general, for an `n`-ary operator, it traverses into the second to last argument.) -/
 syntax (name := lhs) "lhs" : conv
 
-/--
-Traverses into the right subterm of a binary operator.
-
-In general, for an `n`-ary operator, it traverses into the last argument.
-It is a synonym for `arg -1`.
--/
+/-- Traverses into the right subterm of a binary operator.
+(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.
@@ -83,17 +74,13 @@ subgoals for all the function arguments. For example, if the target is `f x y` t
 `congr` produces two subgoals, one for `x` and one for `y`. -/
 syntax (name := congr) "congr" : conv
 
-syntax argArg := "@"? "-"? num
-
 /--
 * `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`.
-  The index may be negative; `arg -1` traverses into the last argument,
-  `arg -2` into the second-to-last argument, and so on.
 * `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`. -/
-syntax (name := arg) "arg " argArg : conv
+syntax (name := arg) "arg " "@"? num : conv
 
 /-- `ext x` traverses into a binder (a `fun x => e` or `∀ x, e` expression)
 to target `e`, introducing name `x` in the process. -/
@@ -143,11 +130,11 @@ For example, if we are searching for `f _` in `f (f a) = f b`:
 syntax (name := pattern) "pattern " (occs)? term : conv
 
 /-- `rw [thm]` rewrites the target using `thm`. See the `rw` tactic for more information. -/
-syntax (name := rewrite) "rewrite" optConfig rwRuleSeq : conv
+syntax (name := rewrite) "rewrite" (config)? rwRuleSeq : conv
 
 /-- `simp [thm]` performs simplification using `thm` and marked `@[simp]` lemmas.
 See the `simp` tactic for more information. -/
-syntax (name := simp) "simp" optConfig (discharger)? (&" only")?
+syntax (name := simp) "simp" (config)? (discharger)? (&" only")?
   (" [" withoutPosition((simpStar <|> simpErase <|> simpLemma),*) "]")? : conv
 
 /--
@@ -164,7 +151,7 @@ example (a : Nat): (0 + 0) = a - a := by
     rw [← Nat.sub_self a]
 ```
 -/
-syntax (name := dsimp) "dsimp" optConfig (discharger)? (&" only")?
+syntax (name := dsimp) "dsimp" (config)? (discharger)? (&" only")?
   (" [" withoutPosition((simpErase <|> simpLemma),*) "]")? : conv
 
 /-- `simp_match` simplifies match expressions. For example,
@@ -260,12 +247,12 @@ macro (name := failIfSuccess) tk:"fail_if_success " s:convSeq : conv =>
 
 /-- `rw [rules]` applies the given list of rewrite rules to the target.
 See the `rw` tactic for more information. -/
-macro "rw" c:optConfig s:rwRuleSeq : conv => `(conv| rewrite $c:optConfig $s)
+macro "rw" c:(config)? s:rwRuleSeq : conv => `(conv| rewrite $[$c]? $s)
 
-/-- `erw [rules]` is a shorthand for `rw (transparency := .default) [rules]`.
+/-- `erw [rules]` is a shorthand for `rw (config := { transparency := .default }) [rules]`.
 This does rewriting up to unfolding of regular definitions (by comparison to regular `rw`
 which only unfolds `@[reducible]` definitions). -/
-macro "erw" c:optConfig s:rwRuleSeq : conv => `(conv| rw $[$(getConfigItems c)]* (transparency := .default) $s:rwRuleSeq)
+macro "erw" s:rwRuleSeq : conv => `(conv| rw (config := { transparency := .default }) $s)
 
 /-- `args` traverses into all arguments. Synonym for `congr`. -/
 macro "args" : conv => `(conv| congr)
@@ -276,7 +263,7 @@ macro "right" : conv => `(conv| rhs)
 /-- `intro` traverses into binders. Synonym for `ext`. -/
 macro "intro" xs:(ppSpace colGt ident)* : conv => `(conv| ext $xs*)
 
-syntax enterArg := ident <|> argArg
+syntax enterArg := ident <|> ("@"? num)
 
 /-- `enter [arg, ...]` is a compact way to describe a path to a subterm.
 It is a shorthand for other conv tactics as follows:
@@ -285,7 +272,12 @@ It is a shorthand for other conv tactics as follows:
 * `enter [x]` (where `x` is an identifier) is equivalent to `ext x`.
 For example, given the target `f (g a (fun x => x b))`, `enter [1, 2, x, 1]`
 will traverse to the subterm `b`. -/
-syntax (name := enter) "enter" " [" withoutPosition(enterArg,+) "]" : conv
+syntax "enter" " [" withoutPosition(enterArg,+) "]" : conv
+macro_rules
+  | `(conv| enter [$i:num]) => `(conv| arg $i)
+  | `(conv| enter [@$i]) => `(conv| arg @$i)
+  | `(conv| enter [$id:ident]) => `(conv| ext $id)
+  | `(conv| enter [$arg, $args,*]) => `(conv| (enter [$arg]; enter [$args,*]))
 
 /-- The `apply thm` conv tactic is the same as `apply thm` the tactic.
 There are no restrictions on `thm`, but strange results may occur if `thm`

src/Init/Data/Array/Basic.lean

@@ -235,11 +235,9 @@ def range (n : Nat) : Array Nat :=
 def singleton (v : α) : Array α :=
   mkArray 1 v
 
-def back! [Inhabited α] (a : Array α) : α :=
+def back [Inhabited α] (a : Array α) : α :=
   a.get! (a.size - 1)
 
-@[deprecated back! (since := "2024-10-31")] abbrev back := @back!
-
 def get? (a : Array α) (i : Nat) : Option α :=
   if h : i < a.size then some a[i] else none
 
@@ -304,6 +302,37 @@ def modifyOp (self : Array α) (idx : Nat) (f : α → α) : Array α :=
   We claim this unsafe implementation is correct because an array cannot have more than `usizeSz` elements in our runtime.
 
   This kind of low level trick can be removed with a little bit of compiler support. For example, if the compiler simplifies `as.size < usizeSz` to true. -/
+@[inline] unsafe def forInUnsafe {α : Type u} {β : Type v} {m : Type v → Type w} [Monad m] (as : Array α) (b : β) (f : α → β → m (ForInStep β)) : m β :=
+  let sz := as.usize
+  let rec @[specialize] loop (i : USize) (b : β) : m β := do
+    if i < sz then
+      let a := as.uget i lcProof
+      match (← f a b) with
+      | ForInStep.done  b => pure b
+      | ForInStep.yield b => loop (i+1) b
+    else
+      pure b
+  loop 0 b
+
+/-- Reference implementation for `forIn` -/
+@[implemented_by Array.forInUnsafe]
+protected def forIn {α : Type u} {β : Type v} {m : Type v → Type w} [Monad m] (as : Array α) (b : β) (f : α → β → m (ForInStep β)) : m β :=
+  let rec loop (i : Nat) (h : i ≤ as.size) (b : β) : m β := do
+    match i, h with
+    | 0,   _ => pure b
+    | i+1, h =>
+      have h' : i < as.size            := Nat.lt_of_lt_of_le (Nat.lt_succ_self i) h
+      have : as.size - 1 < as.size     := Nat.sub_lt (Nat.zero_lt_of_lt h') (by decide)
+      have : as.size - 1 - i < as.size := Nat.lt_of_le_of_lt (Nat.sub_le (as.size - 1) i) this
+      match (← f as[as.size - 1 - i] b) with
+      | ForInStep.done b  => pure b
+      | ForInStep.yield b => loop i (Nat.le_of_lt h') b
+  loop as.size (Nat.le_refl _) b
+
+instance : ForIn m (Array α) α where
+  forIn := Array.forIn
+
+/-- See comment at `forInUnsafe` -/
 @[inline] unsafe def forIn'Unsafe {α : Type u} {β : Type v} {m : Type v → Type w} [Monad m] (as : Array α) (b : β) (f : (a : α) → a ∈ as → β → m (ForInStep β)) : m β :=
   let sz := as.usize
   let rec @[specialize] loop (i : USize) (b : β) : m β := do
@@ -334,9 +363,7 @@ protected def forIn' {α : Type u} {β : Type v} {m : Type v → Type w} [Monad
 instance : ForIn' m (Array α) α inferInstance where
   forIn' := Array.forIn'
 
--- No separate `ForIn` instance is required because it can be derived from `ForIn'`.
-
-/-- See comment at `forIn'Unsafe` -/
+/-- See comment at `forInUnsafe` -/
 @[inline]
 unsafe def foldlMUnsafe {α : Type u} {β : Type v} {m : Type v → Type w} [Monad m] (f : β → α → m β) (init : β) (as : Array α) (start := 0) (stop := as.size) : m β :=
   let rec @[specialize] fold (i : USize) (stop : USize) (b : β) : m β := do
@@ -371,7 +398,7 @@ def foldlM {α : Type u} {β : Type v} {m : Type v → Type w} [Monad m] (f : β
   else
     fold as.size (Nat.le_refl _)
 
-/-- See comment at `forIn'Unsafe` -/
+/-- See comment at `forInUnsafe` -/
 @[inline]
 unsafe def foldrMUnsafe {α : Type u} {β : Type v} {m : Type v → Type w} [Monad m] (f : α → β → m β) (init : β) (as : Array α) (start := as.size) (stop := 0) : m β :=
   let rec @[specialize] fold (i : USize) (stop : USize) (b : β) : m β := do
@@ -410,7 +437,7 @@ def foldrM {α : Type u} {β : Type v} {m : Type v → Type w} [Monad m] (f : α
   else
     pure init
 
-/-- See comment at `forIn'Unsafe` -/
+/-- See comment at `forInUnsafe` -/
 @[inline]
 unsafe def mapMUnsafe {α : Type u} {β : Type v} {m : Type v → Type w} [Monad m] (f : α → m β) (as : Array α) : m (Array β) :=
   let sz := as.usize
@@ -866,7 +893,6 @@ def zip (as : Array α) (bs : Array β) : Array (α × β) :=
 def unzip (as : Array (α × β)) : Array α × Array β :=
   as.foldl (init := (#[], #[])) fun (as, bs) (a, b) => (as.push a, bs.push b)
 
-@[deprecated partition (since := "2024-11-06")]
 def split (as : Array α) (p : α → Bool) : Array α × Array α :=
   as.foldl (init := (#[], #[])) fun (as, bs) a =>
     if p a then (as.push a, bs) else (as, bs.push a)

src/Init/Data/Array/BinSearch.lean

@@ -69,8 +69,8 @@ namespace Array
   if as.isEmpty then do let v ← add (); pure <| as.push v
   else if lt k (as.get! 0) then do let v ← add (); pure <| as.insertAt! 0 v
   else if !lt (as.get! 0) k then as.modifyM 0 <| merge
-  else if lt as.back! k then do let v ← add (); pure <| as.push v
-  else if !lt k as.back! then as.modifyM (as.size - 1) <| merge
+  else if lt as.back k then do let v ← add (); pure <| as.push v
+  else if !lt k as.back then as.modifyM (as.size - 1) <| merge
   else binInsertAux lt merge add as k 0 (as.size - 1)
 
 @[inline] def binInsert {α : Type u} (lt : α → α → Bool) (as : Array α) (k : α) : Array α :=

src/Init/Data/Array/Bootstrap.lean

@@ -23,7 +23,7 @@ theorem foldlM_eq_foldlM_toList.aux [Monad m]
   · cases Nat.not_le_of_gt ‹_› (Nat.zero_add _ ▸ H)
   · rename_i i; rw [Nat.succ_add] at H
     simp [foldlM_eq_foldlM_toList.aux f arr i (j+1) H]
-    rw (occs := .pos [2]) [← List.getElem_cons_drop_succ_eq_drop ‹_›]
+    rw (config := {occs := .pos [2]}) [← List.get_drop_eq_drop _ _ ‹_›]
     rfl
   · rw [List.drop_of_length_le (Nat.ge_of_not_lt ‹_›)]; rfl
 

src/Init/Data/Array/DecidableEq.lean

@@ -13,9 +13,9 @@ import Init.ByCases
 namespace Array
 
 theorem rel_of_isEqvAux
-    {r : α → α → Bool} {a b : Array α} (hsz : a.size = b.size) {i : Nat} (hi : i ≤ a.size)
+    (r : α → α → Bool) (a b : Array α) (hsz : a.size = b.size) (i : Nat) (hi : i ≤ a.size)
     (heqv : Array.isEqvAux a b hsz r i hi)
-    {j : Nat} (hj : j < i) : r (a[j]'(Nat.lt_of_lt_of_le hj hi)) (b[j]'(Nat.lt_of_lt_of_le hj (hsz ▸ hi))) := by
+    (j : Nat) (hj : j < i) : r (a[j]'(Nat.lt_of_lt_of_le hj hi)) (b[j]'(Nat.lt_of_lt_of_le hj (hsz ▸ hi))) := by
   induction i with
   | zero => contradiction
   | succ i ih =>
@@ -28,7 +28,7 @@ theorem rel_of_isEqvAux
       subst hj'
       exact heqv.left
 
-theorem isEqvAux_of_rel {r : α → α → Bool} {a b : Array α} (hsz : a.size = b.size) {i : Nat} (hi : i ≤ a.size)
+theorem isEqvAux_of_rel (r : α → α → Bool) (a b : Array α) (hsz : a.size = b.size) (i : Nat) (hi : i ≤ a.size)
     (w : ∀ j, (hj : j < i) → r (a[j]'(Nat.lt_of_lt_of_le hj hi)) (b[j]'(Nat.lt_of_lt_of_le hj (hsz ▸ hi)))) : Array.isEqvAux a b hsz r i hi := by
   induction i with
   | zero => simp [Array.isEqvAux]
@@ -36,18 +36,18 @@ theorem isEqvAux_of_rel {r : α → α → Bool} {a b : Array α} (hsz : a.size
     simp only [isEqvAux, Bool.and_eq_true]
     exact ⟨w i (Nat.lt_add_one i), ih _ fun j hj => w j (Nat.lt_add_right 1 hj)⟩
 
-theorem rel_of_isEqv {r : α → α → Bool} {a b : Array α} :
+theorem rel_of_isEqv (r : α → α → Bool) (a b : Array α) :
     Array.isEqv a b r → ∃ h : a.size = b.size, ∀ (i : Nat) (h' : i < a.size), r (a[i]) (b[i]'(h ▸ h')) := by
   simp only [isEqv]
   split <;> rename_i h
-  · exact fun h' => ⟨h, fun i => rel_of_isEqvAux h (Nat.le_refl ..) h'⟩
+  · exact fun h' => ⟨h, rel_of_isEqvAux r a b h a.size (Nat.le_refl ..) h'⟩
   · intro; contradiction
 
 theorem isEqv_iff_rel (a b : Array α) (r) :
     Array.isEqv a b r ↔ ∃ h : a.size = b.size, ∀ (i : Nat) (h' : i < a.size), r (a[i]) (b[i]'(h ▸ h')) :=
-  ⟨rel_of_isEqv, fun ⟨h, w⟩ => by
+  ⟨rel_of_isEqv r a b, fun ⟨h, w⟩ => by
     simp only [isEqv, ← h, ↓reduceDIte]
-    exact isEqvAux_of_rel h (by simp [h]) w⟩
+    exact isEqvAux_of_rel r a b h a.size (by simp [h]) w⟩
 
 theorem isEqv_eq_decide (a b : Array α) (r) :
     Array.isEqv a b r =
@@ -67,7 +67,7 @@ theorem isEqv_eq_decide (a b : Array α) (r) :
   simp [isEqv_eq_decide, List.isEqv_eq_decide]
 
 theorem eq_of_isEqv [DecidableEq α] (a b : Array α) (h : Array.isEqv a b (fun x y => x = y)) : a = b := by
-  have ⟨h, h'⟩ := rel_of_isEqv h
+  have ⟨h, h'⟩ := rel_of_isEqv (fun x y => x = y) a b h
   exact ext _ _ h (fun i lt _ => by simpa using h' i lt)
 
 theorem isEqvAux_self (r : α → α → Bool) (hr : ∀ a, r a a) (a : Array α) (i : Nat) (h : i ≤ a.size) :

src/Init/Data/Array/GetLit.lean

@@ -41,6 +41,6 @@ where
   getLit_eq (as : Array α) (i : Nat) (h₁ : as.size = n) (h₂ : i < n) : as.getLit i h₁ h₂ = getElem as.toList i ((id (α := as.toList.length = n) h₁) ▸ h₂) :=
     rfl
   go (i : Nat) (hi : i ≤ as.size) : toListLitAux as n hsz i hi (as.toList.drop i) = as.toList := by
-    induction i <;> simp only [List.drop, toListLitAux, getLit_eq, List.getElem_cons_drop_succ_eq_drop, *]
+    induction i <;> simp only [List.drop, toListLitAux, getLit_eq, List.get_drop_eq_drop, *]
 
 end Array

src/Init/Data/Array/Lemmas.lean

@@ -10,11 +10,7 @@ import Init.Data.List.Monadic
 import Init.Data.List.Range
 import Init.Data.List.Nat.TakeDrop
 import Init.Data.List.Nat.Modify
-import Init.Data.List.Nat.Erase
-import Init.Data.List.Monadic
-import Init.Data.List.OfFn
 import Init.Data.Array.Mem
-import Init.Data.Array.DecidableEq
 import Init.TacticsExtra
 
 /-!
@@ -73,9 +69,6 @@ theorem getElem_push (a : Array α) (x : α) (i : Nat) (h : i < (a.push x).size)
     rfl
   · simp [getElem?_eq_none_iff.2 (by simpa using h)]
 
-theorem singleton_inj : #[a] = #[b] ↔ a = b := by
-  simp
-
 end Array
 
 namespace List
@@ -108,8 +101,27 @@ We prefer to pull `List.toArray` outwards.
 
 @[simp] theorem toArray_singleton (a : α) : (List.singleton a).toArray = singleton a := rfl
 
-@[simp] theorem back!_toArray [Inhabited α] (l : List α) : l.toArray.back! = l.getLast! := by
-  simp only [back!, size_toArray, Array.get!_eq_getElem!, getElem!_toArray, getLast!_eq_getElem!]
+@[simp] theorem back_toArray [Inhabited α] (l : List α) : l.toArray.back = l.getLast! := by
+  simp only [back, size_toArray, Array.get!_eq_getElem!, getElem!_toArray, getLast!_eq_getElem!]
+
+@[simp] theorem forIn_loop_toArray [Monad m] (l : List α) (f : α → β → m (ForInStep β)) (i : Nat)
+    (h : i ≤ l.length) (b : β) :
+    Array.forIn.loop l.toArray f i h b = (l.drop (l.length - i)).forIn b f := by
+  induction i generalizing l b with
+  | zero => simp [Array.forIn.loop]
+  | succ i ih =>
+    simp only [Array.forIn.loop, size_toArray, getElem_toArray, ih, forIn_eq_forIn]
+    rw [Nat.sub_add_eq, List.drop_sub_one (by omega), List.getElem?_eq_getElem (by omega)]
+    simp only [Option.toList_some, singleton_append, forIn_cons]
+    have t : l.length - 1 - i = l.length - i - 1 := by omega
+    simp only [t]
+    congr
+
+@[simp] theorem forIn_toArray [Monad m] (l : List α) (b : β) (f : α → β → m (ForInStep β)) :
+    forIn l.toArray b f = forIn l b f := by
+  change l.toArray.forIn b f = l.forIn b f
+  rw [Array.forIn, forIn_loop_toArray]
+  simp
 
 @[simp] theorem forIn'_loop_toArray [Monad m] (l : List α) (f : (a : α) → a ∈ l.toArray → β → m (ForInStep β)) (i : Nat)
     (h : i ≤ l.length) (b : β) :
@@ -119,7 +131,7 @@ We prefer to pull `List.toArray` outwards.
   | zero =>
     simp [Array.forIn'.loop]
   | succ i ih =>
-    simp only [Array.forIn'.loop, size_toArray, getElem_toArray, ih]
+    simp only [Array.forIn'.loop, size_toArray, getElem_toArray, ih, forIn_eq_forIn]
     have t : drop (l.length - (i + 1)) l = l[l.length - i - 1] :: drop (l.length - i) l := by
       simp only [Nat.sub_add_eq]
       rw [List.drop_sub_one (by omega), List.getElem?_eq_getElem (by omega)]
@@ -133,11 +145,7 @@ We prefer to pull `List.toArray` outwards.
     forIn' l.toArray b f = forIn' l b (fun a m b => f a (mem_toArray.mpr m) b) := by
   change Array.forIn' _ _ _ = List.forIn' _ _ _
   rw [Array.forIn', forIn'_loop_toArray]
-  simp
-
-@[simp] theorem forIn_toArray [Monad m] (l : List α) (b : β) (f : α → β → m (ForInStep β)) :
-    forIn l.toArray b f = forIn l b f := by
-  simpa using forIn'_toArray l b fun a m b => f a b
+  simp [List.forIn_eq_forIn]
 
 theorem foldrM_toArray [Monad m] (f : α → β → m β) (init : β) (l : List α) :
     l.toArray.foldrM f init = l.foldrM f init := by
@@ -214,25 +222,17 @@ theorem foldrM_push [Monad m] (f : α → β → m β) (init : β) (arr : Array
     (arr.push a).foldrM f init = f a init >>= arr.foldrM f := by
   simp [foldrM_eq_reverse_foldlM_toList, -size_push]
 
-/--
-Variant of `foldrM_push` with `h : start = arr.size + 1`
-rather than `(arr.push a).size` as the argument.
--/
-@[simp] theorem foldrM_push' [Monad m] (f : α → β → m β) (init : β) (arr : Array α) (a : α)
-    {start} (h : start = arr.size + 1) :
-    (arr.push a).foldrM f init start = f a init >>= arr.foldrM f := by
-  simp [← foldrM_push, h]
+/-- Variant of `foldrM_push` with the `start := arr.size + 1` rather than `(arr.push a).size`. -/
+@[simp] theorem foldrM_push' [Monad m] (f : α → β → m β) (init : β) (arr : Array α) (a : α) :
+    (arr.push a).foldrM f init (start := arr.size + 1) = f a init >>= arr.foldrM f := by
+  simp [← foldrM_push]
 
 theorem foldr_push (f : α → β → β) (init : β) (arr : Array α) (a : α) :
     (arr.push a).foldr f init = arr.foldr f (f a init) := foldrM_push ..
 
-/--
-Variant of `foldr_push` with the `h : start = arr.size + 1`
-rather than `(arr.push a).size` as the argument.
--/
-@[simp] theorem foldr_push' (f : α → β → β) (init : β) (arr : Array α) (a : α) {start}
-    (h : start = arr.size + 1) : (arr.push a).foldr f init start = arr.foldr f (f a init) :=
-  foldrM_push' _ _ _ _ h
+/-- Variant of `foldr_push` with the `start := arr.size + 1` rather than `(arr.push a).size`. -/
+@[simp] theorem foldr_push' (f : α → β → β) (init : β) (arr : Array α) (a : α) :
+    (arr.push a).foldr f init (start := arr.size + 1) = arr.foldr f (f a init) := foldrM_push' ..
 
 /-- A more efficient version of `arr.toList.reverse`. -/
 @[inline] def toListRev (arr : Array α) : List α := arr.foldl (fun l t => t :: l) []
@@ -247,7 +247,7 @@ where
   aux (i r) :
       mapM.map f arr i r = (arr.toList.drop i).foldlM (fun bs a => bs.push <$> f a) r := by
     unfold mapM.map; split
-    · rw [← List.getElem_cons_drop_succ_eq_drop ‹_›]
+    · rw [← List.get_drop_eq_drop _ i ‹_›]
       simp only [aux (i + 1), map_eq_pure_bind, length_toList, List.foldlM_cons, bind_assoc,
         pure_bind]
       rfl
@@ -506,14 +506,13 @@ theorem getElem?_eq_some_iff {as : Array α} : as[n]? = some a ↔ ∃ h : n < a
   cases as
   simp [List.getElem?_eq_some_iff]
 
-theorem back!_eq_back? [Inhabited α] (a : Array α) : a.back! = a.back?.getD default := by
-  simp only [back!, get!_eq_getElem?, get?_eq_getElem?, back?]
+@[simp] theorem back_eq_back? [Inhabited α] (a : Array α) : a.back = a.back?.getD default := by
+  simp only [back, get!_eq_getElem?, get?_eq_getElem?, back?]
 
 @[simp] theorem back?_push (a : Array α) : (a.push x).back? = some x := by
   simp [back?, getElem?_eq_getElem?_toList]
 
-@[simp] theorem back!_push [Inhabited α] (a : Array α) : (a.push x).back! = x := by
-  simp [back!_eq_back?]
+theorem back_push [Inhabited α] (a : Array α) : (a.push x).back = x := by simp
 
 theorem getElem?_push_lt (a : Array α) (x : α) (i : Nat) (h : i < a.size) :
     (a.push x)[i]? = some a[i] := by
@@ -626,8 +625,8 @@ theorem eq_empty_of_size_eq_zero {as : Array α} (h : as.size = 0) : as = #[] :=
   · simp [h]
   · intros; contradiction
 
-theorem eq_push_pop_back!_of_size_ne_zero [Inhabited α] {as : Array α} (h : as.size ≠ 0) :
-    as = as.pop.push as.back! := by
+theorem eq_push_pop_back_of_size_ne_zero [Inhabited α] {as : Array α} (h : as.size ≠ 0) :
+    as = as.pop.push as.back := by
   apply ext
   · simp [Nat.sub_add_cancel (Nat.zero_lt_of_ne_zero h)]
   · intros i h h'
@@ -636,12 +635,12 @@ theorem eq_push_pop_back!_of_size_ne_zero [Inhabited α] {as : Array α} (h : as
     else
       have heq : i = as.pop.size :=
         Nat.le_antisymm (size_pop .. ▸ Nat.le_pred_of_lt h) (Nat.le_of_not_gt hlt)
-      cases heq; rw [getElem_push_eq, back!, ←size_pop, get!_eq_getD, getD, dif_pos h]; rfl
+      cases heq; rw [getElem_push_eq, back, ←size_pop, get!_eq_getD, getD, dif_pos h]; rfl
 
 theorem eq_push_of_size_ne_zero {as : Array α} (h : as.size ≠ 0) :
     ∃ (bs : Array α) (c : α), as = bs.push c :=
   let _ : Inhabited α := ⟨as[0]⟩
-  ⟨as.pop, as.back!, eq_push_pop_back!_of_size_ne_zero h⟩
+  ⟨as.pop, as.back, eq_push_pop_back_of_size_ne_zero h⟩
 
 theorem size_eq_length_toList (as : Array α) : as.size = as.toList.length := rfl
 
@@ -714,43 +713,6 @@ theorem getElem_range {n : Nat} {x : Nat} (h : x < (Array.range n).size) : (Arra
         true_and, Nat.not_lt] at h
       rw [List.getElem?_eq_none_iff.2 ‹_›, List.getElem?_eq_none_iff.2 (a.toList.length_reverse ▸ ‹_›)]
 
-/-! ### BEq -/
-
-@[simp] theorem reflBEq_iff [BEq α] : ReflBEq (Array α) ↔ ReflBEq α := by
-  constructor
-  · intro h
-    constructor
-    intro a
-    suffices (#[a] == #[a]) = true by
-      simpa only [instBEq, isEqv, isEqvAux, Bool.and_true]
-    simp
-  · intro h
-    constructor
-    apply Array.isEqv_self_beq
-
-@[simp] theorem lawfulBEq_iff [BEq α] : LawfulBEq (Array α) ↔ LawfulBEq α := by
-  constructor
-  · intro h
-    constructor
-    · intro a b h
-      apply singleton_inj.1
-      apply eq_of_beq
-      simp only [instBEq, isEqv, isEqvAux]
-      simpa
-    · intro a
-      suffices (#[a] == #[a]) = true by
-        simpa only [instBEq, isEqv, isEqvAux, Bool.and_true]
-      simp
-  · intro h
-    constructor
-    · intro a b h
-      obtain ⟨hs, hi⟩ := rel_of_isEqv h
-      ext i h₁ h₂
-      · exact hs
-      · simpa using hi _ h₁
-    · intro a
-      apply Array.isEqv_self_beq
-
 /-! ### take -/
 
 @[simp] theorem size_take_loop (a : Array α) (n : Nat) : (take.loop n a).size = a.size - n := by
@@ -910,7 +872,7 @@ theorem map_induction (as : Array α) (f : α → β) (motive : Nat → Prop) (h
   obtain ⟨m, eq, w⟩ := t
   · refine ⟨m, by simpa [map_eq_foldl] using eq, ?_⟩
     intro i h
-    simp only [eq] at w
+    simp [eq] at w
     specialize w ⟨i, h⟩ h
     simpa [map_eq_foldl] using w
   · exact ⟨h0, rfl, nofun⟩
@@ -1461,10 +1423,6 @@ theorem swap_comm (a : Array α) {i j : Fin a.size} : a.swap i j = a.swap j i :=
     · split <;> simp_all
     · split <;> simp_all
 
-theorem feraseIdx_eq_eraseIdx {a : Array α} {i : Fin a.size} :
-    a.feraseIdx i = a.eraseIdx i.1 := by
-  simp [eraseIdx]
-
 end Array
 
 open Array
@@ -1616,98 +1574,13 @@ theorem filterMap_toArray (f : α → Option β) (l : List α) :
   apply ext'
   simp
 
-@[simp] theorem extract_toArray (l : List α) (start stop : Nat) :
+@[simp] theorem toArray_extract (l : List α) (start stop : Nat) :
     l.toArray.extract start stop = ((l.drop start).take (stop - start)).toArray := by
   apply ext'
   simp
 
-@[simp] theorem toArray_ofFn (f : Fin n → α) : (ofFn f).toArray = Array.ofFn f := by
-  ext <;> simp
-
-theorem takeWhile_go_succ (p : α → Bool) (a : α) (l : List α) (i : Nat) :
-    takeWhile.go p (a :: l).toArray (i+1) r = takeWhile.go p l.toArray i r := by
-  rw [takeWhile.go, takeWhile.go]
-  simp only [size_toArray, length_cons, Nat.add_lt_add_iff_right, Array.get_eq_getElem,
-    getElem_toArray, getElem_cons_succ]
-  split
-  rw [takeWhile_go_succ]
-  rfl
-
-theorem takeWhile_go_toArray (p : α → Bool) (l : List α) (i : Nat) :
-    Array.takeWhile.go p l.toArray i r = r ++ (takeWhile p (l.drop i)).toArray := by
-  induction l generalizing i r with
-  | nil => simp [takeWhile.go]
-  | cons a l ih =>
-    rw [takeWhile.go]
-    cases i with
-    | zero =>
-      simp [takeWhile_go_succ, ih, takeWhile_cons]
-      split <;> simp
-    | succ i =>
-      simp only [size_toArray, length_cons, Nat.add_lt_add_iff_right, Array.get_eq_getElem,
-        getElem_toArray, getElem_cons_succ, drop_succ_cons]
-      split <;> rename_i h₁
-      · rw [takeWhile_go_succ, ih]
-        rw [← getElem_cons_drop_succ_eq_drop h₁, takeWhile_cons]
-        split <;> simp_all
-      · simp_all [drop_eq_nil_of_le]
-
-@[simp] theorem takeWhile_toArray (p : α → Bool) (l : List α) :
-    l.toArray.takeWhile p = (l.takeWhile p).toArray := by
-  simp [Array.takeWhile, takeWhile_go_toArray]
-
-@[simp] theorem feraseIdx_toArray (l : List α) (i : Fin l.toArray.size) :
-    l.toArray.feraseIdx i = (l.eraseIdx i).toArray := by
-  rw [feraseIdx]
-  split <;> rename_i h
-  · rw [feraseIdx_toArray]
-    simp only [swap_toArray, Fin.getElem_fin, toList_toArray, mk.injEq]
-    rw [eraseIdx_set_gt (by simp), eraseIdx_set_eq]
-    simp
-  · rcases i with ⟨i, w⟩
-    simp at h w
-    have t : i = l.length - 1 := by omega
-    simp [t]
-termination_by l.length - i
-decreasing_by
-  rename_i h
-  simp at h
-  simp
-  omega
-
-@[simp] theorem eraseIdx_toArray (l : List α) (i : Nat) :
-    l.toArray.eraseIdx i = (l.eraseIdx i).toArray := by
-  rw [Array.eraseIdx]
-  split
-  · simp
-  · simp_all [eraseIdx_eq_self.2]
-
 end List
 
-namespace Array
-
-@[simp] theorem mapM_id {l : Array α} {f : α → Id β} : l.mapM f = l.map f := by
-  induction l; simp_all
-
-@[simp] theorem toList_ofFn (f : Fin n → α) : (Array.ofFn f).toList = List.ofFn f := by
-  apply List.ext_getElem <;> simp
-
-@[simp] theorem toList_takeWhile (p : α → Bool) (as : Array α) :
-    (as.takeWhile p).toList = as.toList.takeWhile p := by
-  induction as; simp
-
-@[simp] theorem toList_feraseIdx (as : Array α) (i : Fin as.size) :
-    (as.feraseIdx i).toList = as.toList.eraseIdx i.1 := by
-  induction as
-  simp
-
-@[simp] theorem toList_eraseIdx (as : Array α) (i : Nat) :
-    (as.eraseIdx i).toList = as.toList.eraseIdx i := by
-  induction as
-  simp
-
-end Array
-
 /-! ### Deprecations -/
 
 namespace List
@@ -1721,8 +1594,6 @@ theorem toArray_concat {as : List α} {x : α} :
   apply ext'
   simp
 
-@[deprecated back!_toArray (since := "2024-10-31")] abbrev back_toArray := @back!_toArray
-
 end List
 
 namespace Array
@@ -1863,9 +1734,4 @@ abbrev get_swap := @getElem_swap
 @[deprecated getElem_swap' (since := "2024-09-30")]
 abbrev get_swap' := @getElem_swap'
 
-@[deprecated back!_eq_back? (since := "2024-10-31")] abbrev back_eq_back? := @back!_eq_back?
-@[deprecated back!_push (since := "2024-10-31")] abbrev back_push := @back!_push
-@[deprecated eq_push_pop_back!_of_size_ne_zero (since := "2024-10-31")]
-abbrev eq_push_pop_back_of_size_ne_zero := @eq_push_pop_back!_of_size_ne_zero
-
 end Array

src/Init/Data/Array/MapIdx.lean

@@ -60,10 +60,6 @@ theorem mapFinIdx_spec (as : Array α) (f : Fin as.size → α → β)
   simp only [getElem?_def, size_mapFinIdx, getElem_mapFinIdx]
   split <;> simp_all
 
-@[simp] theorem toList_mapFinIdx (a : Array α) (f : Fin a.size → α → β) :
-    (a.mapFinIdx f).toList = a.toList.mapFinIdx (fun i a => f ⟨i, by simp⟩ a) := by
-  apply List.ext_getElem <;> simp
-
 /-! ### mapIdx -/
 
 theorem mapIdx_induction (as : Array α) (f : Nat → α → β)
@@ -93,20 +89,4 @@ theorem mapIdx_spec (as : Array α) (f : Nat → α → β)
       a[i]?.map (f i) := by
   simp [getElem?_def, size_mapIdx, getElem_mapIdx]
 
-@[simp] theorem toList_mapIdx (a : Array α) (f : Nat → α → β) :
-    (a.mapIdx f).toList = a.toList.mapIdx (fun i a => f i a) := by
-  apply List.ext_getElem <;> simp
-
 end Array
-
-namespace List
-
-@[simp] theorem mapFinIdx_toArray (l : List α) (f : Fin l.length → α → β) :
-    l.toArray.mapFinIdx f = (l.mapFinIdx f).toArray := by
-  ext <;> simp
-
-@[simp] theorem mapIdx_toArray (l : List α) (f : Nat → α → β) :
-    l.toArray.mapIdx f = (l.mapIdx f).toArray := by
-  ext <;> simp
-
-end List

src/Init/Data/BitVec/Basic.lean

@@ -634,16 +634,6 @@ def twoPow (w : Nat) (i : Nat) : BitVec w := 1#w <<< i
 
 end bitwise
 
-/-- Compute a hash of a bitvector, combining 64-bit words using `mixHash`. -/
-def hash (bv : BitVec n) : UInt64 :=
-  if n ≤ 64 then
-    bv.toFin.val.toUInt64
-  else
-    mixHash (bv.toFin.val.toUInt64) (hash ((bv >>> 64).setWidth (n - 64)))
-
-instance : Hashable (BitVec n) where
-  hash := hash
-
 section normalization_eqs
 /-! We add simp-lemmas that rewrite bitvector operations into the equivalent notation -/
 @[simp] theorem append_eq (x : BitVec w) (y : BitVec v)   : BitVec.append x y = x ++ y        := rfl

src/Init/Data/BitVec/Bitblast.lean

@@ -174,30 +174,6 @@ theorem carry_succ (i : Nat) (x y : BitVec w) (c : Bool) :
     exact mod_two_pow_add_mod_two_pow_add_bool_lt_two_pow_succ ..
   cases x.toNat.testBit i <;> cases y.toNat.testBit i <;> (simp; omega)
 
-theorem carry_succ_one (i : Nat) (x : BitVec w) (h : 0 < w) :
-    carry (i+1) x (1#w) false = decide (∀ j ≤ i, x.getLsbD j = true) := by
-  induction i with
-  | zero => simp [carry_succ, h]
-  | succ i ih =>
-    rw [carry_succ, ih]
-    simp only [getLsbD_one, add_one_ne_zero, decide_False, Bool.and_false, atLeastTwo_false_mid]
-    cases hx : x.getLsbD (i+1)
-    case false =>
-      have : ∃ j ≤ i + 1, x.getLsbD j = false :=
-        ⟨i+1, by omega, hx⟩
-      simpa
-    case true =>
-      suffices
-          (∀ (j : Nat), j ≤ i → x.getLsbD j = true)
-          ↔ (∀ (j : Nat), j ≤ i + 1 → x.getLsbD j = true) by
-        simpa
-      constructor
-      · intro h j hj
-        rcases Nat.le_or_eq_of_le_succ hj with (hj' | rfl)
-        · apply h; assumption
-        · exact hx
-      · intro h j hj; apply h; omega
-
 /--
 If `x &&& y = 0`, then the carry bit `(x + y + 0)` is always `false` for any index `i`.
 Intuitively, this is because a carry is only produced when at least two of `x`, `y`, and the
@@ -376,117 +352,6 @@ theorem bit_neg_eq_neg (x : BitVec w) : -x = (adc (((iunfoldr (fun (i : Fin w) c
     simp [← sub_toAdd, BitVec.sub_add_cancel]
   · simp [bit_not_testBit x _]
 
-/--
-Remember that negating a bitvector is equal to incrementing the complement
-by one, i.e., `-x = ~~~x + 1`. See also `neg_eq_not_add`.
-
-This computation has two crucial properties:
-- The least significant bit of `-x` is the same as the least significant bit of `x`, and
-- The `i+1`-th least significant bit of `-x` is the complement of the `i+1`-th bit of `x`, unless
-  all of the preceding bits are `false`, in which case the bit is equal to the `i+1`-th bit of `x`
--/
-theorem getLsbD_neg {i : Nat} {x : BitVec w} :
-    getLsbD (-x) i =
-      (getLsbD x i ^^ decide (i < w) && decide (∃ j < i, getLsbD x j = true)) := by
-  rw [neg_eq_not_add]
-  by_cases hi : i < w
-  · rw [getLsbD_add hi]
-    have : 0 < w := by omega
-    simp only [getLsbD_not, hi, decide_True, Bool.true_and, getLsbD_one, this, not_bne,
-      _root_.true_and, not_eq_eq_eq_not]
-    cases i with
-    | zero =>
-      have carry_zero : carry 0 ?x ?y false = false := by
-        simp [carry]; omega
-      simp [hi, carry_zero]
-    | succ =>
-      rw [carry_succ_one _ _ (by omega), ← Bool.xor_not, ← decide_not]
-      simp only [add_one_ne_zero, decide_False, getLsbD_not, and_eq_true, decide_eq_true_eq,
-        not_eq_eq_eq_not, Bool.not_true, false_bne, not_exists, _root_.not_and, not_eq_true,
-        bne_left_inj, decide_eq_decide]
-      constructor
-      · rintro h j hj; exact And.right <| h j (by omega)
-      · rintro h j hj; exact ⟨by omega, h j (by omega)⟩
-  · have h_ge : w ≤ i := by omega
-    simp [getLsbD_ge _ _ h_ge, h_ge, hi]
-
-theorem getMsbD_neg {i : Nat} {x : BitVec w} :
-    getMsbD (-x) i =
-      (getMsbD x i ^^ decide (∃ j < w, i < j ∧ getMsbD x j = true)) := by
-  simp only [getMsbD, getLsbD_neg, Bool.decide_and, Bool.and_eq_true, decide_eq_true_eq]
-  by_cases hi : i < w
-  case neg =>
-    simp [hi]; omega
-  case pos =>
-    have h₁ : w - 1 - i < w := by omega
-    simp only [hi, decide_True, h₁, Bool.true_and, Bool.bne_left_inj, decide_eq_decide]
-    constructor
-    · rintro ⟨j, hj, h⟩
-      refine ⟨w - 1 - j, by omega, by omega, by omega, _root_.cast ?_ h⟩
-      congr; omega
-    · rintro ⟨j, hj₁, hj₂, -, h⟩
-      exact ⟨w - 1 - j, by omega, h⟩
-
-theorem msb_neg {w : Nat} {x : BitVec w} :
-    (-x).msb = ((x != 0#w && x != intMin w) ^^ x.msb) := by
-  simp only [BitVec.msb, getMsbD_neg]
-  by_cases hmin : x = intMin _
-  case pos =>
-    have : (∃ j, j < w ∧ 0 < j ∧ 0 < w ∧ j = 0) ↔ False := by
-      simp; omega
-    simp [hmin, getMsbD_intMin, this]
-  case neg =>
-    by_cases hzero : x = 0#w
-    case pos => simp [hzero]
-    case neg =>
-      have w_pos : 0 < w := by
-        cases w
-        · rw [@of_length_zero x] at hzero
-          contradiction
-        · omega
-      suffices ∃ j, j < w ∧ 0 < j ∧ x.getMsbD j = true
-        by simp [show x != 0#w by simpa, show x != intMin w by simpa, this]
-      false_or_by_contra
-      rename_i getMsbD_x
-      simp only [not_exists, _root_.not_and, not_eq_true] at getMsbD_x
-      /- `getMsbD` says that all bits except the msb are `false` -/
-      cases hmsb : x.msb
-      case true =>
-        apply hmin
-        apply eq_of_getMsbD_eq
-        rintro ⟨i, hi⟩
-        simp only [getMsbD_intMin, w_pos, decide_True, Bool.true_and]
-        cases i
-        case zero => exact hmsb
-        case succ => exact getMsbD_x _ hi (by omega)
-      case false =>
-        apply hzero
-        apply eq_of_getMsbD_eq
-        rintro ⟨i, hi⟩
-        simp only [getMsbD_zero]
-        cases i
-        case zero => exact hmsb
-        case succ => exact getMsbD_x _ hi (by omega)
-
-/-! ### abs -/
-
-theorem msb_abs {w : Nat} {x : BitVec w} :
-    x.abs.msb = (decide (x = intMin w) && decide (0 < w)) := by
-  simp only [BitVec.abs, getMsbD_neg, ne_eq, decide_not, Bool.not_bne]
-  by_cases h₀ : 0 < w
-  · by_cases h₁ : x = intMin w
-    · simp [h₁, msb_intMin]
-    · simp only [neg_eq, h₁, decide_False]
-      by_cases h₂ : x.msb
-      · simp [h₂, msb_neg]
-        and_intros
-        · by_cases h₃ : x = 0#w
-          · simp [h₃] at h₂
-          · simp [h₃]
-        · simp [h₁]
-      · simp [h₂]
-  · simp [BitVec.msb, show w = 0 by omega]
-
 /-! ### Inequalities (le / lt) -/
 
 theorem ult_eq_not_carry (x y : BitVec w) : x.ult y = !carry w x (~~~y) true := by

src/Init/Data/BitVec/Lemmas.lean

@@ -1792,7 +1792,7 @@ theorem setWidth_succ (x : BitVec w) :
     · simp_all
     · omega
 
-@[deprecated "Use the reverse direction of `cons_msb_setWidth`" (since := "2024-09-23")]
+@[deprecated "Use the reverse direction of `cons_msb_setWidth`"]
 theorem eq_msb_cons_setWidth (x : BitVec (w+1)) : x = (cons x.msb (x.setWidth w)) := by
   simp
 
@@ -2026,9 +2026,9 @@ theorem sub_def {n} (x y : BitVec n) : x - y = .ofNat n ((2^n - y.toNat) + x.toN
 
 @[simp] theorem toFin_sub (x y : BitVec n) : (x - y).toFin = toFin x - toFin y := rfl
 
-theorem ofFin_sub (x : Fin (2^n)) (y : BitVec n) : .ofFin x - y = .ofFin (x - y.toFin) :=
+@[simp] theorem ofFin_sub (x : Fin (2^n)) (y : BitVec n) : .ofFin x - y = .ofFin (x - y.toFin) :=
   rfl
-theorem sub_ofFin (x : BitVec n) (y : Fin (2^n)) : x - .ofFin y = .ofFin (x.toFin - y) :=
+@[simp] theorem sub_ofFin (x : BitVec n) (y : Fin (2^n)) : x - .ofFin y = .ofFin (x.toFin - y) :=
   rfl
 
 -- Remark: we don't use `[simp]` here because simproc` subsumes it for literals.
@@ -2146,6 +2146,19 @@ theorem not_neg (x : BitVec w) : ~~~(-x) = x + -1#w := by
         show (_ - x.toNat) % _ = _ by rw [Nat.mod_eq_of_lt (by omega)]]
       omega
 
+/-! ### abs -/
+
+theorem abs_eq (x : BitVec w) : x.abs = if x.msb then -x else x := by rfl
+
+@[simp, bv_toNat]
+theorem toNat_abs {x : BitVec w} : x.abs.toNat = if x.msb then 2^w - x.toNat else x.toNat := by
+  simp only [BitVec.abs, neg_eq]
+  by_cases h : x.msb = true
+  · simp only [h, ↓reduceIte, toNat_neg]
+    have : 2 * x.toNat ≥ 2 ^ w := BitVec.msb_eq_true_iff_two_mul_ge.mp h
+    rw [Nat.mod_eq_of_lt (by omega)]
+  · simp [h]
+
 /-! ### mul -/
 
 theorem mul_def {n} {x y : BitVec n} : x * y = (ofFin <| x.toFin * y.toFin) := by rfl
@@ -2886,14 +2899,6 @@ theorem getLsbD_intMin (w : Nat) : (intMin w).getLsbD i = decide (i + 1 = w) :=
   simp only [intMin, getLsbD_twoPow, boolToPropSimps]
   omega
 
-theorem getMsbD_intMin {w i : Nat} :
-    (intMin w).getMsbD i = (decide (0 < w) && decide (i = 0)) := by
-  simp only [getMsbD, getLsbD_intMin]
-  match w, i with
-  | 0,   _    => simp
-  | w+1, 0    => simp
-  | w+1, i+1  => simp; omega
-
 /--
 The RHS is zero in case `w = 0` which is modeled by wrapping the expression in `... % 2 ^ w`.
 -/
@@ -2916,21 +2921,6 @@ theorem toInt_intMin {w : Nat} :
     rw [Nat.mul_comm]
     simp [w_pos]
 
-theorem toInt_intMin_le (x : BitVec w) :
-    (intMin w).toInt ≤ x.toInt := by
-  cases w
-  case zero => simp [@of_length_zero x]
-  case succ w =>
-    simp only [toInt_intMin, Nat.add_one_sub_one, Int.ofNat_emod]
-    have : 0 < 2 ^ w := Nat.two_pow_pos w
-    rw [Int.emod_eq_of_lt (by omega) (by omega)]
-    rw [BitVec.toInt_eq_toNat_bmod]
-    rw [show (2 ^ w : Nat) = ((2 ^ (w + 1) : Nat) : Int) / 2 by omega]
-    apply Int.le_bmod (by omega)
-
-theorem intMin_sle (x : BitVec w) : (intMin w).sle x := by
-  simp only [BitVec.sle, toInt_intMin_le x, decide_True]
-
 @[simp]
 theorem neg_intMin {w : Nat} : -intMin w = intMin w := by
   by_cases h : 0 < w
@@ -2938,10 +2928,6 @@ theorem neg_intMin {w : Nat} : -intMin w = intMin w := by
   · simp only [Nat.not_lt, Nat.le_zero_eq] at h
     simp [bv_toNat, h]
 
-@[simp]
-theorem abs_intMin {w : Nat} : (intMin w).abs = intMin w := by
-  simp [BitVec.abs, bv_toNat]
-
 theorem toInt_neg_of_ne_intMin {x : BitVec w} (rs : x ≠ intMin w) :
     (-x).toInt = -(x.toInt) := by
   simp only [ne_eq, toNat_eq, toNat_intMin] at rs
@@ -2958,10 +2944,6 @@ theorem toInt_neg_of_ne_intMin {x : BitVec w} (rs : x ≠ intMin w) :
   have := @Nat.two_pow_pred_mul_two w (by omega)
   split <;> split <;> omega
 
-theorem msb_intMin {w : Nat} : (intMin w).msb = decide (0 < w) := by
-  simp only [msb_eq_decide, toNat_intMin, decide_eq_decide]
-  by_cases h : 0 < w <;> simp_all
-
 /-! ### intMax -/
 
 /-- The bitvector of width `w` that has the largest value when interpreted as an integer. -/
@@ -3054,38 +3036,6 @@ theorem sub_le_sub_iff_le {x y z : BitVec w} (hxz : z ≤ x) (hyz : z ≤ y) :
     BitVec.toNat_sub_of_le (by rw [BitVec.le_def]; omega)]
   omega
 
-/-! ### neg -/
-
-theorem msb_eq_toInt {x : BitVec w}:
-    x.msb = decide (x.toInt < 0) := by
-  by_cases h : x.msb <;>
-  · simp [h, toInt_eq_msb_cond]
-    omega
-
-theorem msb_eq_toNat {x : BitVec w}:
-    x.msb = decide (x.toNat ≥ 2 ^ (w - 1)) := by
-  simp only [msb_eq_decide, ge_iff_le]
-
-/-! ### abs -/
-
-theorem abs_eq (x : BitVec w) : x.abs = if x.msb then -x else x := by rfl
-
-@[simp, bv_toNat]
-theorem toNat_abs {x : BitVec w} : x.abs.toNat = if x.msb then 2^w - x.toNat else x.toNat := by
-  simp only [BitVec.abs, neg_eq]
-  by_cases h : x.msb = true
-  · simp only [h, ↓reduceIte, toNat_neg]
-    have : 2 * x.toNat ≥ 2 ^ w := BitVec.msb_eq_true_iff_two_mul_ge.mp h
-    rw [Nat.mod_eq_of_lt (by omega)]
-  · simp [h]
-
-theorem getLsbD_abs {i : Nat} {x : BitVec w} :
-   getLsbD x.abs i = if x.msb then getLsbD (-x) i else getLsbD x i := by
-  by_cases h : x.msb <;> simp [BitVec.abs, h]
-
-theorem getMsbD_abs {i : Nat} {x : BitVec w} :
-    getMsbD (x.abs) i = if x.msb then getMsbD (-x) i else getMsbD x i := by
-  by_cases h : x.msb <;> simp [BitVec.abs, h]
 
 /-! ### Decidable quantifiers -/
 

src/Init/Data/Fin/Fold.lean

@@ -5,8 +5,6 @@ Authors: François G. Dorais
 -/
 prelude
 import Init.Data.Nat.Linear
-import Init.Control.Lawful.Basic
-import Init.Data.Fin.Lemmas
 
 namespace Fin
 
@@ -25,195 +23,4 @@ namespace Fin
   | ⟨0, _⟩, x => x
   | ⟨i+1, h⟩, x => loop ⟨i, Nat.le_of_lt h⟩ (f ⟨i, h⟩ x)
 
-/--
-Folds a monadic function over `Fin n` from left to right:
-```
-Fin.foldlM n f x₀ = do
-  let x₁ ← f x₀ 0
-  let x₂ ← f x₁ 1
-  ...
-  let xₙ ← f xₙ₋₁ (n-1)
-  pure xₙ
-```
--/
-@[inline] def foldlM [Monad m] (n) (f : α → Fin n → m α) (init : α) : m α := loop init 0 where
-  /--
-  Inner loop for `Fin.foldlM`.
-  ```
-  Fin.foldlM.loop n f xᵢ i = do
-    let xᵢ₊₁ ← f xᵢ i
-    ...
-    let xₙ ← f xₙ₋₁ (n-1)
-    pure xₙ
-  ```
-  -/
-  loop (x : α) (i : Nat) : m α := do
-    if h : i < n then f x ⟨i, h⟩ >>= (loop · (i+1)) else pure x
-  termination_by n - i
-  decreasing_by decreasing_trivial_pre_omega
-
-/--
-Folds a monadic function over `Fin n` from right to left:
-```
-Fin.foldrM n f xₙ = do
-  let xₙ₋₁ ← f (n-1) xₙ
-  let xₙ₋₂ ← f (n-2) xₙ₋₁
-  ...
-  let x₀ ← f 0 x₁
-  pure x₀
-```
--/
-@[inline] def foldrM [Monad m] (n) (f : Fin n → α → m α) (init : α) : m α :=
-  loop ⟨n, Nat.le_refl n⟩ init where
-  /--
-  Inner loop for `Fin.foldrM`.
-  ```
-  Fin.foldrM.loop n f i xᵢ = do
-    let xᵢ₋₁ ← f (i-1) xᵢ
-    ...
-    let x₁ ← f 1 x₂
-    let x₀ ← f 0 x₁
-    pure x₀
-  ```
-  -/
-  loop : {i // i ≤ n} → α → m α
-  | ⟨0, _⟩, x => pure x
-  | ⟨i+1, h⟩, x => f ⟨i, h⟩ x >>= loop ⟨i, Nat.le_of_lt h⟩
-
-/-! ### foldlM -/
-
-theorem foldlM_loop_lt [Monad m] (f : α → Fin n → m α) (x) (h : i < n) :
-    foldlM.loop n f x i = f x ⟨i, h⟩ >>= (foldlM.loop n f . (i+1)) := by
-  rw [foldlM.loop, dif_pos h]
-
-theorem foldlM_loop_eq [Monad m] (f : α → Fin n → m α) (x) : foldlM.loop n f x n = pure x := by
-  rw [foldlM.loop, dif_neg (Nat.lt_irrefl _)]
-
-theorem foldlM_loop [Monad m] (f : α → Fin (n+1) → m α) (x) (h : i < n+1) :
-    foldlM.loop (n+1) f x i = f x ⟨i, h⟩ >>= (foldlM.loop n (fun x j => f x j.succ) . i) := by
-  if h' : i < n then
-    rw [foldlM_loop_lt _ _ h]
-    congr; funext
-    rw [foldlM_loop_lt _ _ h', foldlM_loop]; rfl
-  else
-    cases Nat.le_antisymm (Nat.le_of_lt_succ h) (Nat.not_lt.1 h')
-    rw [foldlM_loop_lt]
-    congr; funext
-    rw [foldlM_loop_eq, foldlM_loop_eq]
-termination_by n - i
-
-@[simp] theorem foldlM_zero [Monad m] (f : α → Fin 0 → m α) (x) : foldlM 0 f x = pure x :=
-  foldlM_loop_eq ..
-
-theorem foldlM_succ [Monad m] (f : α → Fin (n+1) → m α) (x) :
-    foldlM (n+1) f x = f x 0 >>= foldlM n (fun x j => f x j.succ) := foldlM_loop ..
-
-/-! ### foldrM -/
-
-theorem foldrM_loop_zero [Monad m] (f : Fin n → α → m α) (x) :
-    foldrM.loop n f ⟨0, Nat.zero_le _⟩ x = pure x := by
-  rw [foldrM.loop]
-
-theorem foldrM_loop_succ [Monad m] (f : Fin n → α → m α) (x) (h : i < n) :
-    foldrM.loop n f ⟨i+1, h⟩ x = f ⟨i, h⟩ x >>= foldrM.loop n f ⟨i, Nat.le_of_lt h⟩ := by
-  rw [foldrM.loop]
-
-theorem foldrM_loop [Monad m] [LawfulMonad m] (f : Fin (n+1) → α → m α) (x) (h : i+1 ≤ n+1) :
-    foldrM.loop (n+1) f ⟨i+1, h⟩ x =
-      foldrM.loop n (fun j => f j.succ) ⟨i, Nat.le_of_succ_le_succ h⟩ x >>= f 0 := by
-  induction i generalizing x with
-  | zero =>
-    rw [foldrM_loop_zero, foldrM_loop_succ, pure_bind]
-    conv => rhs; rw [←bind_pure (f 0 x)]
-    congr; funext; exact foldrM_loop_zero ..
-  | succ i ih =>
-    rw [foldrM_loop_succ, foldrM_loop_succ, bind_assoc]
-    congr; funext; exact ih ..
-
-@[simp] theorem foldrM_zero [Monad m] (f : Fin 0 → α → m α) (x) : foldrM 0 f x = pure x :=
-  foldrM_loop_zero ..
-
-theorem foldrM_succ [Monad m] [LawfulMonad m] (f : Fin (n+1) → α → m α) (x) :
-    foldrM (n+1) f x = foldrM n (fun i => f i.succ) x >>= f 0 := foldrM_loop ..
-
-/-! ### foldl -/
-
-theorem foldl_loop_lt (f : α → Fin n → α) (x) (h : i < n) :
-    foldl.loop n f x i = foldl.loop n f (f x ⟨i, h⟩) (i+1) := by
-  rw [foldl.loop, dif_pos h]
-
-theorem foldl_loop_eq (f : α → Fin n → α) (x) : foldl.loop n f x n = x := by
-  rw [foldl.loop, dif_neg (Nat.lt_irrefl _)]
-
-theorem foldl_loop (f : α → Fin (n+1) → α) (x) (h : i < n+1) :
-    foldl.loop (n+1) f x i = foldl.loop n (fun x j => f x j.succ) (f x ⟨i, h⟩) i := by
-  if h' : i < n then
-    rw [foldl_loop_lt _ _ h]
-    rw [foldl_loop_lt _ _ h', foldl_loop]; rfl
-  else
-    cases Nat.le_antisymm (Nat.le_of_lt_succ h) (Nat.not_lt.1 h')
-    rw [foldl_loop_lt]
-    rw [foldl_loop_eq, foldl_loop_eq]
-
-@[simp] theorem foldl_zero (f : α → Fin 0 → α) (x) : foldl 0 f x = x :=
-  foldl_loop_eq ..
-
-theorem foldl_succ (f : α → Fin (n+1) → α) (x) :
-    foldl (n+1) f x = foldl n (fun x i => f x i.succ) (f x 0) :=
-  foldl_loop ..
-
-theorem foldl_succ_last (f : α → Fin (n+1) → α) (x) :
-    foldl (n+1) f x = f (foldl n (f · ·.castSucc) x) (last n) := by
-  rw [foldl_succ]
-  induction n generalizing x with
-  | zero => simp [foldl_succ, Fin.last]
-  | succ n ih => rw [foldl_succ, ih (f · ·.succ), foldl_succ]; simp [succ_castSucc]
-
-theorem foldl_eq_foldlM (f : α → Fin n → α) (x) :
-    foldl n f x = foldlM (m:=Id) n f x := by
-  induction n generalizing x <;> simp [foldl_succ, foldlM_succ, *]
-
-/-! ### foldr -/
-
-theorem foldr_loop_zero (f : Fin n → α → α) (x) :
-    foldr.loop n f ⟨0, Nat.zero_le _⟩ x = x := by
-  rw [foldr.loop]
-
-theorem foldr_loop_succ (f : Fin n → α → α) (x) (h : i < n) :
-    foldr.loop n f ⟨i+1, h⟩ x = foldr.loop n f ⟨i, Nat.le_of_lt h⟩ (f ⟨i, h⟩ x) := by
-  rw [foldr.loop]
-
-theorem foldr_loop (f : Fin (n+1) → α → α) (x) (h : i+1 ≤ n+1) :
-    foldr.loop (n+1) f ⟨i+1, h⟩ x =
-      f 0 (foldr.loop n (fun j => f j.succ) ⟨i, Nat.le_of_succ_le_succ h⟩ x) := by
-  induction i generalizing x <;> simp [foldr_loop_zero, foldr_loop_succ, *]
-
-@[simp] theorem foldr_zero (f : Fin 0 → α → α) (x) : foldr 0 f x = x :=
-  foldr_loop_zero ..
-
-theorem foldr_succ (f : Fin (n+1) → α → α) (x) :
-    foldr (n+1) f x = f 0 (foldr n (fun i => f i.succ) x) := foldr_loop ..
-
-theorem foldr_succ_last (f : Fin (n+1) → α → α) (x) :
-    foldr (n+1) f x = foldr n (f ·.castSucc) (f (last n) x) := by
-  induction n generalizing x with
-  | zero => simp [foldr_succ, Fin.last]
-  | succ n ih => rw [foldr_succ, ih (f ·.succ), foldr_succ]; simp [succ_castSucc]
-
-theorem foldr_eq_foldrM (f : Fin n → α → α) (x) :
-    foldr n f x = foldrM (m:=Id) n f x := by
-  induction n <;> simp [foldr_succ, foldrM_succ, *]
-
-theorem foldl_rev (f : Fin n → α → α) (x) :
-    foldl n (fun x i => f i.rev x) x = foldr n f x := by
-  induction n generalizing x with
-  | zero => simp
-  | succ n ih => rw [foldl_succ, foldr_succ_last, ← ih]; simp [rev_succ]
-
-theorem foldr_rev (f : α → Fin n → α) (x) :
-     foldr n (fun i x => f x i.rev) x = foldl n f x := by
-  induction n generalizing x with
-  | zero => simp
-  | succ n ih => rw [foldl_succ_last, foldr_succ, ← ih]; simp [rev_succ]
-
 end Fin

src/Init/Data/Hashable.lean

@@ -48,9 +48,6 @@ instance : Hashable UInt64 where
 instance : Hashable USize where
   hash n := n.toUInt64
 
-instance : Hashable ByteArray where
-  hash as := as.foldl (fun r a => mixHash r (hash a)) 7
-
 instance : Hashable (Fin n) where
   hash v := v.val.toUInt64
 

src/Init/Data/Int/DivModLemmas.lean

@@ -1267,7 +1267,7 @@ theorem bmod_le {x : Int} {m : Nat} (h : 0 < m) : bmod x m ≤ (m - 1) / 2 := by
     _ = ((m + 1 - 2) + 2)/2 := by simp
     _ = (m - 1) / 2 + 1     := by
       rw [add_ediv_of_dvd_right]
-      · simp +decide only [Int.ediv_self]
+      · simp (config := {decide := true}) only [Int.ediv_self]
         congr 2
         rw [Int.add_sub_assoc, ← Int.sub_neg]
         congr
@@ -1285,7 +1285,7 @@ theorem bmod_natAbs_plus_one (x : Int) (w : 1 < x.natAbs) : bmod x (x.natAbs + 1
     simp only [bmod, ofNat_eq_coe, natAbs_ofNat, natCast_add, ofNat_one,
       emod_self_add_one (ofNat_nonneg x)]
     match x with
-    | 0 => rw [if_pos] <;> simp +decide
+    | 0 => rw [if_pos] <;> simp (config := {decide := true})
     | (x+1) =>
       rw [if_neg]
       · simp [← Int.sub_sub]

src/Init/Data/Int/Order.lean

@@ -1007,9 +1007,9 @@ theorem sign_eq_neg_one_iff_neg {a : Int} : sign a = -1 ↔ a < 0 :=
   match x with
   | 0 => rfl
   | .ofNat (_ + 1) =>
-    simp +decide only [sign, true_iff]
+    simp (config := { decide := true }) only [sign, true_iff]
     exact Int.le_add_one (ofNat_nonneg _)
-  | .negSucc _ => simp +decide [sign]
+  | .negSucc _ => simp (config := { decide := true }) [sign]
 
 theorem mul_sign : ∀ i : Int, i * sign i = natAbs i
   | succ _ => Int.mul_one _

src/Init/Data/List.lean

@@ -25,4 +25,3 @@ import Init.Data.List.Perm
 import Init.Data.List.Sort
 import Init.Data.List.ToArray
 import Init.Data.List.MapIdx
-import Init.Data.List.OfFn

src/Init/Data/List/Attach.lean

@@ -169,13 +169,6 @@ theorem pmap_ne_nil_iff {P : α → Prop} (f : (a : α) → P a → β) {xs : Li
     (H : ∀ (a : α), a ∈ xs → P a) : xs.pmap f H ≠ [] ↔ xs ≠ [] := by
   simp
 
-theorem pmap_eq_self {l : List α} {p : α → Prop} (hp : ∀ (a : α), a ∈ l → p a)
-    (f : (a : α) → p a → α) : l.pmap f hp = l ↔ ∀ a (h : a ∈ l), f a (hp a h) = a := by
-  rw [pmap_eq_map_attach]
-  conv => lhs; rhs; rw [← attach_map_subtype_val l]
-  rw [map_inj_left]
-  simp
-
 @[simp]
 theorem attach_eq_nil_iff {l : List α} : l.attach = [] ↔ l = [] :=
   pmap_eq_nil_iff

src/Init/Data/List/Basic.lean

@@ -45,7 +45,7 @@ The operations are organized as follow:
 * Zippers: `zipWith`, `zip`, `zipWithAll`, and `unzip`.
 * Ranges and enumeration: `range`, `iota`, `enumFrom`, and `enum`.
 * Minima and maxima: `min?` and `max?`.
-* Other functions: `intersperse`, `intercalate`, `eraseDups`, `eraseReps`, `span`, `splitBy`,
+* Other functions: `intersperse`, `intercalate`, `eraseDups`, `eraseReps`, `span`, `groupBy`,
   `removeAll`
   (currently these functions are mostly only used in meta code,
   and do not have API suitable for verification).
@@ -1639,23 +1639,23 @@ where
     | true  => loop as (a::rs)
     | false => (rs.reverse, a::as)
 
-/-! ### splitBy -/
+/-! ### groupBy -/
 
 /--
-`O(|l|)`. `splitBy R l` splits `l` into chains of elements
+`O(|l|)`. `groupBy R l` splits `l` into chains of elements
 such that adjacent elements are related by `R`.
 
-* `splitBy (·==·) [1, 1, 2, 2, 2, 3, 2] = [[1, 1], [2, 2, 2], [3], [2]]`
-* `splitBy (·<·) [1, 2, 5, 4, 5, 1, 4] = [[1, 2, 5], [4, 5], [1, 4]]`
+* `groupBy (·==·) [1, 1, 2, 2, 2, 3, 2] = [[1, 1], [2, 2, 2], [3], [2]]`
+* `groupBy (·<·) [1, 2, 5, 4, 5, 1, 4] = [[1, 2, 5], [4, 5], [1, 4]]`
 -/
-@[specialize] def splitBy (R : α → α → Bool) : List α → List (List α)
+@[specialize] def groupBy (R : α → α → Bool) : List α → List (List α)
   | []    => []
   | a::as => loop as a [] []
 where
   /--
-  The arguments of `splitBy.loop l ag g gs` represent the following:
+  The arguments of `groupBy.loop l ag g gs` represent the following:
 
-  - `l : List α` are the elements which we still need to split.
+  - `l : List α` are the elements which we still need to group.
   - `ag : α` is the previous element for which a comparison was performed.
   - `g : List α` is the group currently being assembled, in **reverse order**.
   - `gs : List (List α)` is all of the groups that have been completed, in **reverse order**.
@@ -1666,8 +1666,6 @@ where
     | false => loop as a [] ((ag::g).reverse::gs)
   | [], ag, g, gs => ((ag::g).reverse::gs).reverse
 
-@[deprecated splitBy (since := "2024-10-30"), inherit_doc splitBy] abbrev groupBy := @splitBy
-
 /-! ### removeAll -/
 
 /-- `O(|xs|)`. Computes the "set difference" of lists,

src/Init/Data/List/Control.lean

@@ -215,6 +215,27 @@ def findSomeM? {m : Type u → Type v} [Monad m] {α : Type w} {β : Type u} (f
     | some b => pure (some b)
     | none   => findSomeM? f as
 
+@[inline] protected def forIn {α : Type u} {β : Type v} {m : Type v → Type w} [Monad m] (as : List α) (init : β) (f : α → β → m (ForInStep β)) : m β :=
+  let rec @[specialize] loop
+    | [], b    => pure b
+    | a::as, b => do
+      match (← f a b) with
+      | ForInStep.done b  => pure b
+      | ForInStep.yield b => loop as b
+  loop as init
+
+instance : ForIn m (List α) α where
+  forIn := List.forIn
+
+@[simp] theorem forIn_eq_forIn [Monad m] : @List.forIn α β m _ = forIn := rfl
+
+@[simp] theorem forIn_nil [Monad m] (f : α → β → m (ForInStep β)) (b : β) : forIn [] b f = pure b :=
+  rfl
+
+@[simp] theorem forIn_cons [Monad m] (f : α → β → m (ForInStep β)) (a : α) (as : List α) (b : β)
+    : forIn (a::as) b f = f a b >>= fun | ForInStep.done b => pure b | ForInStep.yield b => forIn as b f :=
+  rfl
+
 @[inline] protected def forIn' {α : Type u} {β : Type v} {m : Type v → Type w} [Monad m] (as : List α) (init : β) (f : (a : α) → a ∈ as → β → m (ForInStep β)) : m β :=
   let rec @[specialize] loop : (as' : List α) → (b : β) → Exists (fun bs => bs ++ as' = as) → m β
     | [], b, _    => pure b
@@ -233,15 +254,16 @@ def findSomeM? {m : Type u → Type v} [Monad m] {α : Type w} {β : Type u} (f
 instance : ForIn' m (List α) α inferInstance where
   forIn' := List.forIn'
 
--- No separate `ForIn` instance is required because it can be derived from `ForIn'`.
-
 @[simp] theorem forIn'_eq_forIn' [Monad m] : @List.forIn' α β m _ = forIn' := rfl
 
-@[simp] theorem forIn'_nil [Monad m] (f : (a : α) → a ∈ [] → β → m (ForInStep β)) (b : β) : forIn' [] b f = pure b :=
-  rfl
-
-@[simp] theorem forIn_nil [Monad m] (f : α → β → m (ForInStep β)) (b : β) : forIn [] b f = pure b :=
-  rfl
+@[simp] theorem forIn'_eq_forIn {α : Type u} {β : Type v} {m : Type v → Type w} [Monad m] (as : List α) (init : β) (f : α → β → m (ForInStep β)) : forIn' as init (fun a _ b => f a b) = forIn as init f := by
+  simp [forIn', forIn, List.forIn, List.forIn']
+  have : ∀ cs h, List.forIn'.loop cs (fun a _ b => f a b) as init h = List.forIn.loop f as init := by
+    intro cs h
+    induction as generalizing cs init with
+    | nil => intros; rfl
+    | cons a as ih => intros; simp [List.forIn.loop, List.forIn'.loop, ih]
+  apply this
 
 instance : ForM m (List α) α where
   forM := List.forM

src/Init/Data/List/Count.lean

@@ -153,7 +153,7 @@ theorem countP_filterMap (p : β → Bool) (f : α → Option β) (l : List α)
   simp only [length_filterMap_eq_countP]
   congr
   ext a
-  simp +contextual [Option.getD_eq_iff, Option.isSome_eq_isSome]
+  simp (config := { contextual := true }) [Option.getD_eq_iff, Option.isSome_eq_isSome]
 
 @[simp] theorem countP_flatten (l : List (List α)) :
     countP p l.flatten = (l.map (countP p)).sum := by
@@ -315,7 +315,7 @@ theorem replicate_count_eq_of_count_eq_length {l : List α} (h : count a l = len
 theorem count_le_count_map [DecidableEq β] (l : List α) (f : α → β) (x : α) :
     count x l ≤ count (f x) (map f l) := by
   rw [count, count, countP_map]
-  apply countP_mono_left; simp +contextual
+  apply countP_mono_left; simp (config := { contextual := true })
 
 theorem count_filterMap {α} [BEq β] (b : β) (f : α → Option β) (l : List α) :
     count b (filterMap f l) = countP (fun a => f a == some b) l := by

src/Init/Data/List/Find.lean

@@ -179,7 +179,7 @@ theorem IsPrefix.findSome?_eq_some {l₁ l₂ : List α} {f : α → Option β}
     List.findSome? f l₁ = some b → List.findSome? f l₂ = some b := by
   rw [IsPrefix] at h
   obtain ⟨t, rfl⟩ := h
-  simp +contextual [findSome?_append]
+  simp (config := {contextual := true}) [findSome?_append]
 
 theorem IsPrefix.findSome?_eq_none {l₁ l₂ : List α} {f : α → Option β} (h : l₁ <+: l₂) :
     List.findSome? f l₂ = none → List.findSome? f l₁ = none :=
@@ -436,7 +436,7 @@ theorem IsPrefix.find?_eq_some {l₁ l₂ : List α} {p : α → Bool} (h : l₁
     List.find? p l₁ = some b → List.find? p l₂ = some b := by
   rw [IsPrefix] at h
   obtain ⟨t, rfl⟩ := h
-  simp +contextual [find?_append]
+  simp (config := {contextual := true}) [find?_append]
 
 theorem IsPrefix.find?_eq_none {l₁ l₂ : List α} {p : α → Bool} (h : l₁ <+: l₂) :
     List.find? p l₂ = none → List.find? p l₁ = none :=
@@ -562,7 +562,7 @@ theorem not_of_lt_findIdx {p : α → Bool} {xs : List α} {i : Nat} (h : i < xs
     | inr e =>
       have ipm := Nat.succ_pred_eq_of_pos e
       have ilt := Nat.le_trans ho (findIdx_le_length p)
-      simp +singlePass only [← ipm, getElem_cons_succ]
+      simp (config := { singlePass := true }) only [← ipm, getElem_cons_succ]
       rw [← ipm, Nat.succ_lt_succ_iff] at h
       simpa using ih h
 

src/Init/Data/List/Impl.lean

@@ -23,7 +23,7 @@ namespace List
 The following operations are already tail-recursive, and do not need `@[csimp]` replacements:
 `get`, `foldl`, `beq`, `isEqv`, `reverse`, `elem` (and hence `contains`), `drop`, `dropWhile`,
 `partition`, `isPrefixOf`, `isPrefixOf?`, `find?`, `findSome?`, `lookup`, `any` (and hence `or`),
-`all` (and hence `and`) , `range`, `eraseDups`, `eraseReps`, `span`, `splitBy`.
+`all` (and hence `and`) , `range`, `eraseDups`, `eraseReps`, `span`, `groupBy`.
 
 The following operations are still missing `@[csimp]` replacements:
 `concat`, `zipWithAll`.

src/Init/Data/List/Lemmas.lean

@@ -3328,7 +3328,7 @@ theorem all_eq_not_any_not (l : List α) (p : α → Bool) : l.all p = !l.any (!
 
 @[simp] theorem all_replicate {n : Nat} {a : α} :
     (replicate n a).all f = if n = 0 then true else f a := by
-  cases n <;> simp +contextual [replicate_succ]
+  cases n <;> simp (config := {contextual := true}) [replicate_succ]
 
 @[simp] theorem any_insert [BEq α] [LawfulBEq α] {l : List α} {a : α} :
     (l.insert a).any f = (f a || l.any f) := by

src/Init/Data/List/MapIdx.lean

@@ -7,9 +7,6 @@ Authors: Kim Morrison, Mario Carneiro
 prelude
 import Init.Data.Array.Lemmas
 import Init.Data.List.Nat.Range
-import Init.Data.List.OfFn
-import Init.Data.Fin.Lemmas
-import Init.Data.Option.Attach
 
 namespace List
 
@@ -17,21 +14,8 @@ namespace List
 
 /-! ### mapIdx -/
 
-
 /--
-Given a list `as = [a₀, a₁, ...]` function `f : Fin as.length → α → β`, returns the list
-`[f 0 a₀, f 1 a₁, ...]`.
--/
-@[inline] def mapFinIdx (as : List α) (f : Fin as.length → α → β) : List β := go as #[] (by simp) where
-  /-- Auxiliary for `mapFinIdx`:
-  `mapFinIdx.go [a₀, a₁, ...] acc = acc.toList ++ [f 0 a₀, f 1 a₁, ...]` -/
-  @[specialize] go : (bs : List α) → (acc : Array β) → bs.length + acc.size = as.length → List β
-  | [], acc, h => acc.toList
-  | a :: as, acc, h =>
-    go as (acc.push (f ⟨acc.size, by simp at h; omega⟩ a)) (by simp at h ⊢; omega)
-
-/--
-Given a function `f : Nat → α → β` and `as : List α`, `as = [a₀, a₁, ...]`, returns the list
+Given a function `f : Nat → α → β` and `as : list α`, `as = [a₀, a₁, ...]`, returns the list
 `[f 0 a₀, f 1 a₁, ...]`.
 -/
 @[inline] def mapIdx (f : Nat → α → β) (as : List α) : List β := go as #[] where
@@ -41,177 +25,34 @@ Given a function `f : Nat → α → β` and `as : List α`, `as = [a₀, a₁,
   | [], acc => acc.toList
   | a :: as, acc => go as (acc.push (f acc.size a))
 
-/-! ### mapFinIdx -/
-
-@[simp]
-theorem mapFinIdx_nil {f : Fin 0 → α → β} : mapFinIdx [] f = [] :=
-  rfl
-
-@[simp] theorem length_mapFinIdx_go :
-    (mapFinIdx.go as f bs acc h).length = as.length := by
-  induction bs generalizing acc with
-  | nil => simpa using h
-  | cons _ _ ih => simp [mapFinIdx.go, ih]
-
-@[simp] theorem length_mapFinIdx {as : List α} {f : Fin as.length → α → β} :
-    (as.mapFinIdx f).length = as.length := by
-  simp [mapFinIdx, length_mapFinIdx_go]
-
-theorem getElem_mapFinIdx_go {as : List α} {f : Fin as.length → α → β} {i : Nat} {h} {w} :
-    (mapFinIdx.go as f bs acc h)[i] =
-      if w' : i < acc.size then acc[i] else f ⟨i, by simp at w; omega⟩ (bs[i - acc.size]'(by simp at w; omega)) := by
-  induction bs generalizing acc with
-  | nil =>
-    simp only [length_mapFinIdx_go, length_nil, Nat.zero_add] at w h
-    simp only [mapFinIdx.go, Array.getElem_toList]
-    rw [dif_pos]
-  | cons _ _ ih =>
-    simp [mapFinIdx.go]
-    rw [ih]
-    simp
-    split <;> rename_i h₁ <;> split <;> rename_i h₂
-    · rw [Array.getElem_push_lt]
-    · have h₃ : i = acc.size := by omega
-      subst h₃
-      simp
-    · omega
-    · have h₃ : i - acc.size = (i - (acc.size + 1)) + 1 := by omega
-      simp [h₃]
-
-@[simp] theorem getElem_mapFinIdx {as : List α} {f : Fin as.length → α → β} {i : Nat} {h} :
-    (as.mapFinIdx f)[i] = f ⟨i, by simp at h; omega⟩ (as[i]'(by simp at h; omega)) := by
-  simp [mapFinIdx, getElem_mapFinIdx_go]
-
-theorem mapFinIdx_eq_ofFn {as : List α} {f : Fin as.length → α → β} :
-    as.mapFinIdx f = List.ofFn fun i : Fin as.length => f i as[i] := by
-  apply ext_getElem <;> simp
-
-@[simp] theorem getElem?_mapFinIdx {l : List α} {f : Fin l.length → α → β} {i : Nat} :
-    (l.mapFinIdx f)[i]? = l[i]?.pbind fun x m => f ⟨i, by simp [getElem?_eq_some] at m; exact m.1⟩ x := by
-  simp only [getElem?_eq, length_mapFinIdx, getElem_mapFinIdx]
-  split <;> simp
-
-@[simp]
-theorem mapFinIdx_cons {l : List α} {a : α} {f : Fin (l.length + 1) → α → β} :
-    mapFinIdx (a :: l) f = f 0 a :: mapFinIdx l (fun i => f i.succ) := by
-  apply ext_getElem
-  · simp
-  · rintro (_|i) h₁ h₂ <;> simp
-
-theorem mapFinIdx_append {K L : List α} {f : Fin (K ++ L).length → α → β} :
-    (K ++ L).mapFinIdx f =
-      K.mapFinIdx (fun i => f (i.castLE (by simp))) ++ L.mapFinIdx (fun i => f ((i.natAdd K.length).cast (by simp))) := by
-  apply ext_getElem
-  · simp
-  · intro i h₁ h₂
-    rw [getElem_append]
-    simp only [getElem_mapFinIdx, length_mapFinIdx]
-    split <;> rename_i h
-    · rw [getElem_append_left]
-      congr
-    · simp only [Nat.not_lt] at h
-      rw [getElem_append_right h]
-      congr
-      simp
-      omega
-
-@[simp] theorem mapFinIdx_concat {l : List α} {e : α} {f : Fin (l ++ [e]).length → α → β}:
-    (l ++ [e]).mapFinIdx f = l.mapFinIdx (fun i => f (i.castLE (by simp))) ++ [f ⟨l.length, by simp⟩ e] := by
-  simp [mapFinIdx_append]
-  congr
-
-theorem mapFinIdx_singleton {a : α} {f : Fin 1 → α → β} :
-    [a].mapFinIdx f = [f ⟨0, by simp⟩ a] := by
-  simp
-
-theorem mapFinIdx_eq_enum_map {l : List α} {f : Fin l.length → α → β} :
-    l.mapFinIdx f = l.enum.attach.map
-      fun ⟨⟨i, x⟩, m⟩ => f ⟨i, by rw [mk_mem_enum_iff_getElem?, getElem?_eq_some] at m; exact m.1⟩ x := by
-  apply ext_getElem <;> simp
-
-@[simp]
-theorem mapFinIdx_eq_nil_iff {l : List α} {f : Fin l.length → α → β} :
-    l.mapFinIdx f = [] ↔ l = [] := by
-  rw [mapFinIdx_eq_enum_map, map_eq_nil_iff, attach_eq_nil_iff, enum_eq_nil_iff]
-
-theorem mapFinIdx_ne_nil_iff {l : List α} {f : Fin l.length → α → β} :
-    l.mapFinIdx f ≠ [] ↔ l ≠ [] := by
-  simp
-
-theorem exists_of_mem_mapFinIdx {b : β} {l : List α} {f : Fin l.length → α → β}
-    (h : b ∈ l.mapFinIdx f) : ∃ (i : Fin l.length), f i l[i] = b := by
-  rw [mapFinIdx_eq_enum_map] at h
-  replace h := exists_of_mem_map h
-  simp only [mem_attach, true_and, Subtype.exists, Prod.exists, mk_mem_enum_iff_getElem?] at h
-  obtain ⟨i, b, h, rfl⟩ := h
-  rw [getElem?_eq_some_iff] at h
-  obtain ⟨h', rfl⟩ := h
-  exact ⟨⟨i, h'⟩, rfl⟩
-
-@[simp] theorem mem_mapFinIdx {b : β} {l : List α} {f : Fin l.length → α → β} :
-    b ∈ l.mapFinIdx f ↔ ∃ (i : Fin l.length), f i l[i] = b := by
-  constructor
-  · intro h
-    exact exists_of_mem_mapFinIdx h
-  · rintro ⟨i, h, rfl⟩
-    rw [mem_iff_getElem]
-    exact ⟨i, by simp⟩
-
-theorem mapFinIdx_eq_cons_iff {l : List α} {b : β} {f : Fin l.length → α → β} :
-    l.mapFinIdx f = b :: l₂ ↔
-      ∃ (a : α) (l₁ : List α) (h : l = a :: l₁),
-        f ⟨0, by simp [h]⟩ a = b ∧ l₁.mapFinIdx (fun i => f (i.succ.cast (by simp [h]))) = l₂ := by
-  cases l with
-  | nil => simp
-  | cons x l' =>
-    simp only [mapFinIdx_cons, cons.injEq, length_cons, Fin.zero_eta, Fin.cast_succ_eq,
-      exists_and_left]
-    constructor
-    · rintro ⟨rfl, rfl⟩
-      refine ⟨x, rfl, l', by simp⟩
-    · rintro ⟨a, ⟨rfl, h⟩, ⟨_, ⟨rfl, rfl⟩, h⟩⟩
-      exact ⟨rfl, h⟩
-
-theorem mapFinIdx_eq_cons_iff' {l : List α} {b : β} {f : Fin l.length → α → β} :
-    l.mapFinIdx f = b :: l₂ ↔
-      l.head?.pbind (fun x m => (f ⟨0, by cases l <;> simp_all⟩ x)) = some b ∧
-        l.tail?.attach.map (fun ⟨t, m⟩ => t.mapFinIdx fun i => f (i.succ.cast (by cases l <;> simp_all))) = some l₂ := by
-  cases l <;> simp
-
-theorem mapFinIdx_eq_iff {l : List α} {f : Fin l.length → α → β} :
-    l.mapFinIdx f = l' ↔ ∃ h : l'.length = l.length, ∀ (i : Nat) (h : i < l.length), l'[i] = f ⟨i, h⟩ l[i] := by
-  constructor
-  · rintro rfl
-    simp
-  · rintro ⟨h, w⟩
-    apply ext_getElem <;> simp_all
-
-theorem mapFinIdx_eq_mapFinIdx_iff {l : List α} {f g : Fin l.length → α → β} :
-    l.mapFinIdx f = l.mapFinIdx g ↔ ∀ (i : Fin l.length), f i l[i] = g i l[i] := by
-  rw [eq_comm, mapFinIdx_eq_iff]
-  simp [Fin.forall_iff]
-
-@[simp] theorem mapFinIdx_mapFinIdx {l : List α} {f : Fin l.length → α → β} {g : Fin _ → β → γ} :
-    (l.mapFinIdx f).mapFinIdx g = l.mapFinIdx (fun i => g (i.cast (by simp)) ∘ f i) := by
-  simp [mapFinIdx_eq_iff]
-
-theorem mapFinIdx_eq_replicate_iff {l : List α} {f : Fin l.length → α → β} {b : β} :
-    l.mapFinIdx f = replicate l.length b ↔ ∀ (i : Fin l.length), f i l[i] = b := by
-  simp [eq_replicate_iff, length_mapFinIdx, mem_mapFinIdx, forall_exists_index, true_and]
-
-@[simp] theorem mapFinIdx_reverse {l : List α} {f : Fin l.reverse.length → α → β} :
-    l.reverse.mapFinIdx f = (l.mapFinIdx (fun i => f ⟨l.length - 1 - i, by simp; omega⟩)).reverse := by
-  simp [mapFinIdx_eq_iff]
-  intro i h
-  congr
-  omega
-
-/-! ### mapIdx -/
-
 @[simp]
 theorem mapIdx_nil {f : Nat → α → β} : mapIdx f [] = [] :=
   rfl
 
+theorem mapIdx_go_append  {l₁ l₂ : List α} {arr : Array β} :
+    mapIdx.go f (l₁ ++ l₂) arr = mapIdx.go f l₂ (List.toArray (mapIdx.go f l₁ arr)) := by
+  generalize h : (l₁ ++ l₂).length = len
+  induction len generalizing l₁ arr with
+  | zero =>
+    have l₁_nil : l₁ = [] := by
+      cases l₁
+      · rfl
+      · contradiction
+    have l₂_nil : l₂ = [] := by
+      cases l₂
+      · rfl
+      · rw [List.length_append] at h; contradiction
+    rw [l₁_nil, l₂_nil]; simp only [mapIdx.go, List.toArray_toList]
+  | succ len ih =>
+    cases l₁ with
+    | nil =>
+      simp only [mapIdx.go, nil_append, List.toArray_toList]
+    | cons head tail =>
+      simp only [mapIdx.go, List.append_eq]
+      rw [ih]
+      · simp only [cons_append, length_cons, length_append, Nat.succ.injEq] at h
+        simp only [length_append, h]
+
 theorem mapIdx_go_length {arr : Array β} :
     length (mapIdx.go f l arr) = length l + arr.size := by
   induction l generalizing arr with
@@ -219,6 +60,16 @@ theorem mapIdx_go_length {arr : Array β} :
   | cons _ _ ih =>
     simp only [mapIdx.go, ih, Array.size_push, Nat.add_succ, length_cons, Nat.add_comm]
 
+@[simp] theorem mapIdx_concat {l : List α} {e : α} :
+    mapIdx f (l ++ [e]) = mapIdx f l ++ [f l.length e] := by
+  unfold mapIdx
+  rw [mapIdx_go_append]
+  simp only [mapIdx.go, Array.size_toArray, mapIdx_go_length, length_nil, Nat.add_zero,
+    Array.push_toList]
+
+@[simp] theorem mapIdx_singleton {a : α} : mapIdx f [a] = [f 0 a] := by
+  simpa using mapIdx_concat (l := [])
+
 theorem length_mapIdx_go : ∀ {l : List α} {arr : Array β},
     (mapIdx.go f l arr).length = l.length + arr.size
   | [], _ => by simp [mapIdx.go]
@@ -261,15 +112,6 @@ theorem getElem?_mapIdx_go : ∀ {l : List α} {arr : Array β} {i : Nat},
   rw [← getElem?_eq_getElem, getElem?_mapIdx, getElem?_eq_getElem (by simpa using h)]
   simp
 
-@[simp] theorem mapFinIdx_eq_mapIdx {l : List α} {f : Fin l.length → α → β} {g : Nat → α → β}
-    (h : ∀ (i : Fin l.length), f i l[i] = g i l[i]) :
-    l.mapFinIdx f = l.mapIdx g := by
-  simp_all [mapFinIdx_eq_iff]
-
-theorem mapIdx_eq_mapFinIdx {l : List α} {f : Nat → α → β} :
-    l.mapIdx f = l.mapFinIdx (fun i => f i) := by
-  simp [mapFinIdx_eq_mapIdx]
-
 theorem mapIdx_eq_enum_map {l : List α} :
     l.mapIdx f = l.enum.map (Function.uncurry f) := by
   ext1 i
@@ -288,16 +130,9 @@ theorem mapIdx_append {K L : List α} :
   | nil => rfl
   | cons _ _ ih => simp [ih (f := fun i => f (i + 1)), Nat.add_assoc]
 
-@[simp] theorem mapIdx_concat {l : List α} {e : α} :
-    mapIdx f (l ++ [e]) = mapIdx f l ++ [f l.length e] := by
-  simp [mapIdx_append]
-
-theorem mapIdx_singleton {a : α} : mapIdx f [a] = [f 0 a] := by
-  simp
-
 @[simp]
 theorem mapIdx_eq_nil_iff {l : List α} : List.mapIdx f l = [] ↔ l = [] := by
-  rw [List.mapIdx_eq_enum_map, List.map_eq_nil_iff, List.enum_eq_nil_iff]
+  rw [List.mapIdx_eq_enum_map, List.map_eq_nil_iff, List.enum_eq_nil]
 
 theorem mapIdx_ne_nil_iff {l : List α} :
     List.mapIdx f l ≠ [] ↔ l ≠ [] := by
@@ -305,8 +140,13 @@ theorem mapIdx_ne_nil_iff {l : List α} :
 
 theorem exists_of_mem_mapIdx {b : β} {l : List α}
     (h : b ∈ mapIdx f l) : ∃ (i : Nat) (h : i < l.length), f i l[i] = b := by
-  rw [mapIdx_eq_mapFinIdx] at h
-  simpa [Fin.exists_iff] using exists_of_mem_mapFinIdx h
+  rw [mapIdx_eq_enum_map] at h
+  replace h := exists_of_mem_map h
+  simp only [Prod.exists, mk_mem_enum_iff_getElem?, Function.uncurry_apply_pair] at h
+  obtain ⟨i, b, h, rfl⟩ := h
+  rw [getElem?_eq_some_iff] at h
+  obtain ⟨h, rfl⟩ := h
+  exact ⟨i, h, rfl⟩
 
 @[simp] theorem mem_mapIdx {b : β} {l : List α} :
     b ∈ mapIdx f l ↔ ∃ (i : Nat) (h : i < l.length), f i l[i] = b := by

src/Init/Data/List/Monadic.lean

@@ -5,7 +5,6 @@ Authors: Parikshit Khanna, Jeremy Avigad, Leonardo de Moura, Floris van Doorn, M
 -/
 prelude
 import Init.Data.List.TakeDrop
-import Init.Data.List.Attach
 
 /-!
 # Lemmas about `List.mapM` and `List.forM`.
@@ -49,9 +48,6 @@ theorem mapM'_eq_mapM [Monad m] [LawfulMonad m] (f : α → m β) (l : List α)
 @[simp] theorem mapM_cons [Monad m] [LawfulMonad m] (f : α → m β) :
     (a :: l).mapM f = (return (← f a) :: (← l.mapM f)) := by simp [← mapM'_eq_mapM, mapM']
 
-@[simp] theorem mapM_id {l : List α} {f : α → Id β} : l.mapM f = l.map f := by
-  induction l <;> simp_all
-
 @[simp] theorem mapM_append [Monad m] [LawfulMonad m] (f : α → m β) {l₁ l₂ : List α} :
     (l₁ ++ l₂).mapM f = (return (← l₁.mapM f) ++ (← l₂.mapM f)) := by induction l₁ <;> simp [*]
 
@@ -76,16 +72,6 @@ theorem mapM_eq_reverse_foldlM_cons [Monad m] [LawfulMonad m] (f : α → m β)
       reverse_cons, reverse_nil, nil_append, singleton_append]
     simp [bind_pure_comp]
 
-/-! ### foldlM and foldrM -/
-
-theorem foldlM_map [Monad m] (f : β₁ → β₂) (g : α → β₂ → m α) (l : List β₁) (init : α) :
-    (l.map f).foldlM g init = l.foldlM (fun x y => g x (f y)) init := by
-  induction l generalizing g init <;> simp [*]
-
-theorem foldrM_map [Monad m] [LawfulMonad m] (f : β₁ → β₂) (g : β₂ → α → m α) (l : List β₁)
-    (init : α) : (l.map f).foldrM g init = l.foldrM (fun x y => g (f x) y) init := by
-  induction l generalizing g init <;> simp [*]
-
 /-! ### forM -/
 
 -- We use `List.forM` as the simp normal form, rather that `ForM.forM`.
@@ -103,6 +89,9 @@ theorem foldrM_map [Monad m] [LawfulMonad m] (f : β₁ → β₂) (g : β₂
 
 /-! ### forIn' -/
 
+@[simp] theorem forIn'_nil [Monad m] (f : (a : α) → a ∈ [] → β → m (ForInStep β)) (b : β) : forIn' [] b f = pure b :=
+  rfl
+
 theorem forIn'_loop_congr [Monad m] {as bs : List α}
     {f : (a' : α) → a' ∈ as → β → m (ForInStep β)}
     {g : (a' : α) → a' ∈ bs → β → m (ForInStep β)}
@@ -133,11 +122,6 @@ theorem forIn'_loop_congr [Monad m] {as bs : List α}
     intros
     rfl
 
-@[simp] theorem forIn_cons [Monad m] (f : α → β → m (ForInStep β)) (a : α) (as : List α) (b : β) :
-    forIn (a::as) b f = f a b >>= fun | ForInStep.done b => pure b | ForInStep.yield b => forIn as b f := by
-  have := forIn'_cons (a := a) (as := as) (fun a' _ b => f a' b) b
-  simpa only [forIn'_eq_forIn]
-
 @[congr] theorem forIn'_congr [Monad m] {as bs : List α} (w : as = bs)
     {b b' : β} (hb : b = b')
     {f : (a' : α) → a' ∈ as → β → m (ForInStep β)}
@@ -165,65 +149,6 @@ theorem forIn'_loop_congr [Monad m] {as bs : List α}
           intro a m b
           exact h a (mem_cons_of_mem _ m) b
 
-/--
-We can express a for loop over a list as a fold,
-in which whenever we reach `.done b` we keep that value through the rest of the fold.
--/
-theorem forIn'_eq_foldlM [Monad m] [LawfulMonad m]
-    (l : List α) (f : (a : α) → a ∈ l → β → m (ForInStep β)) (init : β) :
-    forIn' l init f = ForInStep.value <$>
-      l.attach.foldlM (fun b a => match b with
-        | .yield b => f a.1 a.2 b
-        | .done b => pure (.done b)) (ForInStep.yield init) := by
-  induction l generalizing init with
-  | nil => simp
-  | cons a as ih =>
-    simp only [forIn'_cons, attach_cons, foldlM_cons, _root_.map_bind]
-    congr 1
-    funext x
-    match x with
-    | .done b =>
-      clear ih
-      dsimp
-      induction as with
-      | nil => simp
-      | cons a as ih =>
-        simp only [attach_cons, map_cons, map_map, Function.comp_def, foldlM_cons, pure_bind]
-        specialize ih (fun a m b => f a (by
-          simp only [mem_cons] at m
-          rcases m with rfl|m
-          · apply mem_cons_self
-          · exact mem_cons_of_mem _ (mem_cons_of_mem _ m)) b)
-        simp [ih, List.foldlM_map]
-    | .yield b =>
-      simp [ih, List.foldlM_map]
-
-/--
-We can express a for loop over a list as a fold,
-in which whenever we reach `.done b` we keep that value through the rest of the fold.
--/
-theorem forIn_eq_foldlM [Monad m] [LawfulMonad m]
-    (f : α → β → m (ForInStep β)) (init : β) (l : List α) :
-    forIn l init f = ForInStep.value <$>
-      l.foldlM (fun b a => match b with
-        | .yield b => f a b
-        | .done b => pure (.done b)) (ForInStep.yield init) := by
-  induction l generalizing init with
-  | nil => simp
-  | cons a as ih =>
-    simp only [foldlM_cons, bind_pure_comp, forIn_cons, _root_.map_bind]
-    congr 1
-    funext x
-    match x with
-    | .done b =>
-      clear ih
-      dsimp
-      induction as with
-      | nil => simp
-      | cons a as ih => simp [ih]
-    | .yield b =>
-      simp [ih]
-
 /-! ### allM -/
 
 theorem allM_eq_not_anyM_not [Monad m] [LawfulMonad m] (p : α → m Bool) (as : List α) :
@@ -236,4 +161,14 @@ theorem allM_eq_not_anyM_not [Monad m] [LawfulMonad m] (p : α → m Bool) (as :
     funext b
     split <;> simp_all
 
+/-! ### foldlM and foldrM -/
+
+theorem foldlM_map [Monad m] (f : β₁ → β₂) (g : α → β₂ → m α) (l : List β₁) (init : α) :
+    (l.map f).foldlM g init = l.foldlM (fun x y => g x (f y)) init := by
+  induction l generalizing g init <;> simp [*]
+
+theorem foldrM_map [Monad m] [LawfulMonad m] (f : β₁ → β₂) (g : β₂ → α → m α) (l : List β₁)
+    (init : α) : (l.map f).foldrM g init = l.foldrM (fun x y => g (f x) y) init := by
+  induction l generalizing g init <;> simp [*]
+
 end List

src/Init/Data/List/Nat/Erase.lean

@@ -64,82 +64,3 @@ theorem getElem_eraseIdx_of_ge (l : List α) (i : Nat) (j : Nat) (h : j < (l.era
     (l.eraseIdx i)[j] = l[j + 1]'(by rw [length_eraseIdx] at h; split at h <;> omega) := by
   rw [getElem_eraseIdx, dif_neg]
   omega
-
-theorem eraseIdx_set_eq {l : List α} {i : Nat} {a : α} :
-    (l.set i a).eraseIdx i = l.eraseIdx i := by
-  apply ext_getElem
-  · simp [length_eraseIdx]
-  · intro n h₁ h₂
-    rw [getElem_eraseIdx, getElem_eraseIdx]
-    split <;>
-    · rw [getElem_set_ne]
-      omega
-
-theorem eraseIdx_set_lt {l : List α} {i : Nat} {j : Nat} {a : α} (h : j < i) :
-    (l.set i a).eraseIdx j = (l.eraseIdx j).set (i - 1) a := by
-  apply ext_getElem
-  · simp [length_eraseIdx]
-  · intro n h₁ h₂
-    simp only [length_eraseIdx, length_set] at h₁
-    simp only [getElem_eraseIdx, getElem_set]
-    split
-    · split
-      · split
-        · rfl
-        · omega
-      · split
-        · omega
-        · rfl
-    · split
-      · split
-        · rfl
-        · omega
-      · have t : i - 1 ≠ n := by omega
-        simp [t]
-
-theorem eraseIdx_set_gt {l : List α} {i : Nat} {j : Nat} {a : α} (h : i < j) :
-    (l.set i a).eraseIdx j = (l.eraseIdx j).set i a := by
-  apply ext_getElem
-  · simp [length_eraseIdx]
-  · intro n h₁ h₂
-    simp only [length_eraseIdx, length_set] at h₁
-    simp only [getElem_eraseIdx, getElem_set]
-    split
-    · rfl
-    · split
-      · split
-        · rfl
-        · omega
-      · have t : i ≠ n := by omega
-        simp [t]
-
-@[simp] theorem set_getElem_succ_eraseIdx_succ
-    {l : List α} {i : Nat} (h : i + 1 < l.length) :
-    (l.eraseIdx (i + 1)).set i l[i + 1] = l.eraseIdx i := by
-  apply ext_getElem
-  · simp only [length_set, length_eraseIdx, h, ↓reduceIte]
-    rw [if_pos]
-    omega
-  · intro n h₁ h₂
-    simp [getElem_set, getElem_eraseIdx]
-    split
-    · split
-      · omega
-      · simp_all
-    · split
-      · split
-        · rfl
-        · omega
-      · have t : ¬ n < i := by omega
-        simp [t]
-
-@[simp] theorem eraseIdx_length_sub_one (l : List α) :
-    (l.eraseIdx (l.length - 1)) = l.dropLast := by
-  apply ext_getElem
-  · simp [length_eraseIdx]
-    omega
-  · intro n h₁ h₂
-    rw [getElem_eraseIdx_of_lt, getElem_dropLast]
-    simp_all
-
-end List

src/Init/Data/List/Nat/Range.lean

@@ -169,7 +169,7 @@ theorem not_mem_range_self {n : Nat} : n ∉ range n := by simp
 theorem self_mem_range_succ (n : Nat) : n ∈ range (n + 1) := by simp
 
 theorem pairwise_lt_range (n : Nat) : Pairwise (· < ·) (range n) := by
-  simp +decide only [range_eq_range', pairwise_lt_range']
+  simp (config := {decide := true}) only [range_eq_range', pairwise_lt_range']
 
 theorem pairwise_le_range (n : Nat) : Pairwise (· ≤ ·) (range n) :=
   Pairwise.imp Nat.le_of_lt (pairwise_lt_range _)
@@ -177,10 +177,10 @@ theorem pairwise_le_range (n : Nat) : Pairwise (· ≤ ·) (range n) :=
 theorem take_range (m n : Nat) : take m (range n) = range (min m n) := by
   apply List.ext_getElem
   · simp
-  · simp +contextual [getElem_take, Nat.lt_min]
+  · simp (config := { contextual := true }) [getElem_take, Nat.lt_min]
 
 theorem nodup_range (n : Nat) : Nodup (range n) := by
-  simp +decide only [range_eq_range', nodup_range']
+  simp (config := {decide := true}) only [range_eq_range', nodup_range']
 
 @[simp] theorem find?_range_eq_some {n : Nat} {i : Nat} {p : Nat → Bool} :
     (range n).find? p = some i ↔ p i ∧ i ∈ range n ∧ ∀ j, j < i → !p j := by
@@ -430,10 +430,7 @@ theorem enumFrom_eq_append_iff {l : List α} {n : Nat} :
 /-! ### enum -/
 
 @[simp]
-theorem enum_eq_nil_iff {l : List α} : List.enum l = [] ↔ l = [] := enumFrom_eq_nil
-
-@[deprecated enum_eq_nil_iff (since := "2024-11-04")]
-theorem enum_eq_nil {l : List α} : List.enum l = [] ↔ l = [] := enum_eq_nil_iff
+theorem enum_eq_nil {l : List α} : List.enum l = [] ↔ l = [] := enumFrom_eq_nil
 
 @[simp] theorem enum_singleton (x : α) : enum [x] = [(0, x)] := rfl
 

src/Init/Data/List/OfFn.lean

@@ -1,55 +0,0 @@
-/-
-Copyright (c) 2024 Lean FRO. All rights reserved.
-Released under Apache 2.0 license as described in the file LICENSE.
-Authors: Mario Carneiro, Kim Morrison
--/
-prelude
-import Init.Data.List.Basic
-import Init.Data.Fin.Fold
-
-/-!
-# Theorems about `List.ofFn`
--/
-
-namespace List
-
-/--
-`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) : List α := Fin.foldr n (f · :: ·) []
-
-@[simp]
-theorem length_ofFn (f : Fin n → α) : (ofFn f).length = n := by
-  simp only [ofFn]
-  induction n with
-  | zero => simp
-  | succ n ih => simp [Fin.foldr_succ, ih]
-
-@[simp]
-protected theorem getElem_ofFn (f : Fin n → α) (i : Nat) (h : i < (ofFn f).length) :
-    (ofFn f)[i] = f ⟨i, by simp_all⟩ := by
-  simp only [ofFn]
-  induction n generalizing i with
-  | zero => simp at h
-  | succ n ih =>
-    match i with
-    | 0 => simp [Fin.foldr_succ]
-    | i+1 =>
-      simp only [Fin.foldr_succ]
-      apply ih
-      simp_all
-
-@[simp]
-protected theorem getElem?_ofFn (f : Fin n → α) (i) : (ofFn f)[i]? = if h : i < n then some (f ⟨i, h⟩) else none :=
-  if h : i < (ofFn f).length
-  then by
-    rw [getElem?_eq_getElem h, List.getElem_ofFn]
-    · simp only [length_ofFn] at h; simp [h]
-  else by
-    rw [dif_neg] <;>
-    simpa using h
-
-end List

src/Init/Data/List/Pairwise.lean

@@ -76,11 +76,11 @@ theorem pairwise_of_forall {l : List α} (H : ∀ x y, R x y) : Pairwise R l :=
 
 theorem Pairwise.and_mem {l : List α} :
     Pairwise R l ↔ Pairwise (fun x y => x ∈ l ∧ y ∈ l ∧ R x y) l :=
-  Pairwise.iff_of_mem <| by simp +contextual
+  Pairwise.iff_of_mem <| by simp (config := { contextual := true })
 
 theorem Pairwise.imp_mem {l : List α} :
     Pairwise R l ↔ Pairwise (fun x y => x ∈ l → y ∈ l → R x y) l :=
-  Pairwise.iff_of_mem <| by simp +contextual
+  Pairwise.iff_of_mem <| by simp (config := { contextual := true })
 
 theorem Pairwise.forall_of_forall_of_flip (h₁ : ∀ x ∈ l, R x x) (h₂ : Pairwise R l)
     (h₃ : l.Pairwise (flip R)) : ∀ ⦃x⦄, x ∈ l → ∀ ⦃y⦄, y ∈ l → R x y := by

src/Init/Data/List/Sublist.lean

@@ -116,7 +116,7 @@ fun s => Subset.trans s <| subset_append_right _ _
 theorem replicate_subset {n : Nat} {a : α} {l : List α} : replicate n a ⊆ l ↔ n = 0 ∨ a ∈ l := by
   induction n with
   | zero => simp
-  | succ n ih => simp +contextual [replicate_succ, ih, cons_subset]
+  | succ n ih => simp (config := {contextual := true}) [replicate_succ, ih, cons_subset]
 
 theorem subset_replicate {n : Nat} {a : α} {l : List α} (h : n ≠ 0) : l ⊆ replicate n a ↔ ∀ x ∈ l, x = a := by
   induction l with
@@ -835,7 +835,7 @@ theorem isPrefix_iff : l₁ <+: l₂ ↔ ∀ i (h : i < l₁.length), l₂[i]? =
       simpa using ⟨0, by simp⟩
     | cons b l₂ =>
       simp only [cons_append, cons_prefix_cons, ih]
-      rw (occs := .pos [2]) [← Nat.and_forall_add_one]
+      rw (config := {occs := .pos [2]}) [← Nat.and_forall_add_one]
       simp [Nat.succ_lt_succ_iff, eq_comm]
 
 theorem isPrefix_iff_getElem {l₁ l₂ : List α} :

src/Init/Data/List/TakeDrop.lean

@@ -190,7 +190,7 @@ theorem set_drop {l : List α} {n m : Nat} {a : α} :
 theorem take_concat_get (l : List α) (i : Nat) (h : i < l.length) :
     (l.take i).concat l[i] = l.take (i+1) :=
   Eq.symm <| (append_left_inj _).1 <| (take_append_drop (i+1) l).trans <| by
-    rw [concat_eq_append, append_assoc, singleton_append, getElem_cons_drop_succ_eq_drop, take_append_drop]
+    rw [concat_eq_append, append_assoc, singleton_append, get_drop_eq_drop, take_append_drop]
 
 @[deprecated take_succ_cons (since := "2024-07-25")]
 theorem take_cons_succ : (a::as).take (i+1) = a :: as.take i := rfl

src/Init/Data/Nat/Dvd.lean

@@ -92,7 +92,7 @@ protected theorem div_mul_cancel {n m : Nat} (H : n ∣ m) : m / n * n = m := by
   rw [Nat.mul_comm, Nat.mul_div_cancel' H]
 
 @[simp] theorem mod_mod_of_dvd (a : Nat) (h : c ∣ b) : a % b % c = a % c := by
-  rw (occs := .pos [2]) [← mod_add_div a b]
+  rw (config := {occs := .pos [2]}) [← mod_add_div a b]
   have ⟨x, h⟩ := h
   subst h
   rw [Nat.mul_assoc, add_mul_mod_self_left]

src/Init/Data/Nat/Lemmas.lean

@@ -651,8 +651,8 @@ theorem sub_mul_mod {x k n : Nat} (h₁ : n*k ≤ x) : (x - n*k) % n = x % n :=
   | .inr npos => Nat.mod_eq_of_lt (mod_lt _ npos)
 
 theorem mul_mod (a b n : Nat) : a * b % n = (a % n) * (b % n) % n := by
-  rw (occs := .pos [1]) [← mod_add_div a n]
-  rw (occs := .pos [1]) [← mod_add_div b n]
+  rw (config := {occs := .pos [1]}) [← mod_add_div a n]
+  rw (config := {occs := .pos [1]}) [← mod_add_div b n]
   rw [Nat.add_mul, Nat.mul_add, Nat.mul_add,
     Nat.mul_assoc, Nat.mul_assoc, ← Nat.mul_add n, add_mul_mod_self_left,
     Nat.mul_comm _ (n * (b / n)), Nat.mul_assoc, add_mul_mod_self_left]

src/Init/Data/Option/Instances.lean

@@ -86,6 +86,4 @@ instance : ForIn' m (Option α) α inferInstance where
       match ← f a rfl init with
       | .done r | .yield r => return r
 
--- No separate `ForIn` instance is required because it can be derived from `ForIn'`.
-
 end Option

src/Init/Data/Option/Lemmas.lean

@@ -374,15 +374,9 @@ end choice
 
 -- See `Init.Data.Option.List` for lemmas about `toList`.
 
-@[simp] theorem some_or : (some a).or o = some a := rfl
+@[simp] theorem or_some : (some a).or o = some a := rfl
 @[simp] theorem none_or : none.or o = o := rfl
 
-@[deprecated some_or (since := "2024-11-03")] theorem or_some : (some a).or o = some a := rfl
-
-/-- This will be renamed to `or_some` once the existing deprecated lemma is removed. -/
-@[simp] theorem or_some' {o : Option α} : o.or (some a) = o.getD a := by
-  cases o <;> rfl
-
 theorem or_eq_bif : or o o' = bif o.isSome then o else o' := by
   cases o <;> rfl
 

src/Init/Data/Range.lean

@@ -20,6 +20,21 @@ instance : Membership Nat Range where
 namespace Range
 universe u v
 
+@[inline] protected def forIn {β : Type u} {m : Type u → Type v} [Monad m] (range : Range) (init : β) (f : Nat → β → m (ForInStep β)) : m β :=
+  -- pass `stop` and `step` separately so the `range` object can be eliminated through inlining
+  let rec @[specialize] loop (fuel i stop step : Nat) (b : β) : m β := do
+    if i ≥ stop then
+      return b
+    else match fuel with
+     | 0   => pure b
+     | fuel+1 => match (← f i b) with
+        | ForInStep.done b  => pure b
+        | ForInStep.yield b => loop fuel (i + step) stop step b
+  loop range.stop range.start range.stop range.step init
+
+instance : ForIn m Range Nat where
+  forIn := Range.forIn
+
 @[inline] protected def forIn' {β : Type u} {m : Type u → Type v} [Monad m] (range : Range) (init : β) (f : (i : Nat) → i ∈ range → β → m (ForInStep β)) : m β :=
   let rec @[specialize] loop (start stop step : Nat) (f : (i : Nat) → start ≤ i ∧ i < stop → β → m (ForInStep β)) (fuel i : Nat) (hl : start ≤ i) (b : β) : m β := do
     if hu : i < stop then
@@ -35,8 +50,6 @@ universe u v
 instance : ForIn' m Range Nat inferInstance where
   forIn' := Range.forIn'
 
--- No separate `ForIn` instance is required because it can be derived from `ForIn'`.
-
 @[inline] protected def forM {m : Type u → Type v} [Monad m] (range : Range) (f : Nat → m PUnit) : m PUnit :=
   let rec @[specialize] loop (fuel i stop step : Nat) : m PUnit := do
     if i ≥ stop then

src/Init/Data/SInt/Basic.lean

@@ -22,48 +22,6 @@ structure Int8 where
   -/
   toUInt8 : UInt8
 
-/--
-The type of signed 16-bit integers. This type has special support in the
-compiler to make it actually 16 bits rather than wrapping a `Nat`.
--/
-structure Int16 where
-  /--
-  Obtain the `UInt16` that is 2's complement equivalent to the `Int16`.
-  -/
-  toUInt16 : UInt16
-
-/--
-The type of signed 32-bit integers. This type has special support in the
-compiler to make it actually 32 bits rather than wrapping a `Nat`.
--/
-structure Int32 where
-  /--
-  Obtain the `UInt32` that is 2's complement equivalent to the `Int32`.
-  -/
-  toUInt32 : UInt32
-
-/--
-The type of signed 64-bit integers. This type has special support in the
-compiler to make it actually 64 bits rather than wrapping a `Nat`.
--/
-structure Int64 where
-  /--
-  Obtain the `UInt64` that is 2's complement equivalent to the `Int64`.
-  -/
-  toUInt64 : UInt64
-
-/--
-A `ISize` is a signed integer with the size of a word for the platform's architecture.
-
-For example, if running on a 32-bit machine, ISize is equivalent to `Int32`.
-Or on a 64-bit machine, `Int64`.
--/
-structure ISize where
-  /--
-  Obtain the `USize` that is 2's complement equivalent to the `ISize`.
-  -/
-  toUSize : USize
-
 /-- The size of type `Int8`, that is, `2^8 = 256`. -/
 abbrev Int8.size : Nat := 256
 
@@ -74,16 +32,12 @@ Obtain the `BitVec` that contains the 2's complement representation of the `Int8
 
 @[extern "lean_int8_of_int"]
 def Int8.ofInt (i : @& Int) : Int8 := ⟨⟨BitVec.ofInt 8 i⟩⟩
-@[extern "lean_int8_of_nat"]
+@[extern "lean_int8_of_int"]
 def Int8.ofNat (n : @& Nat) : Int8 := ⟨⟨BitVec.ofNat 8 n⟩⟩
 abbrev Int.toInt8 := Int8.ofInt
 abbrev Nat.toInt8 := Int8.ofNat
 @[extern "lean_int8_to_int"]
 def Int8.toInt (i : Int8) : Int := i.toBitVec.toInt
-/--
-This function has the same behavior as `Int.toNat` for negative numbers.
-If you want to obtain the 2's complement representation use `toBitVec`.
--/
 @[inline] def Int8.toNat (i : Int8) : Nat := i.toInt.toNat
 @[extern "lean_int8_neg"]
 def Int8.neg (i : Int8) : Int8 := ⟨⟨-i.toBitVec⟩⟩
@@ -104,7 +58,7 @@ def Int8.mul (a b : Int8) : Int8 := ⟨⟨a.toBitVec * b.toBitVec⟩⟩
 @[extern "lean_int8_div"]
 def Int8.div (a b : Int8) : Int8 := ⟨⟨BitVec.sdiv a.toBitVec b.toBitVec⟩⟩
 @[extern "lean_int8_mod"]
-def Int8.mod (a b : Int8) : Int8 := ⟨⟨BitVec.srem a.toBitVec b.toBitVec⟩⟩
+def Int8.mod (a b : Int8) : Int8 := ⟨⟨BitVec.smod a.toBitVec b.toBitVec⟩⟩
 @[extern "lean_int8_land"]
 def Int8.land (a b : Int8) : Int8 := ⟨⟨a.toBitVec &&& b.toBitVec⟩⟩
 @[extern "lean_int8_lor"]
@@ -112,9 +66,9 @@ def Int8.lor (a b : Int8) : Int8 := ⟨⟨a.toBitVec ||| b.toBitVec⟩⟩
 @[extern "lean_int8_xor"]
 def Int8.xor (a b : Int8) : Int8 := ⟨⟨a.toBitVec ^^^ b.toBitVec⟩⟩
 @[extern "lean_int8_shift_left"]
-def Int8.shiftLeft (a b : Int8) : Int8 := ⟨⟨a.toBitVec <<< (b.toBitVec.smod 8)⟩⟩
+def Int8.shiftLeft (a b : Int8) : Int8 := ⟨⟨a.toBitVec <<< (mod b 8).toBitVec⟩⟩
 @[extern "lean_int8_shift_right"]
-def Int8.shiftRight (a b : Int8) : Int8 := ⟨⟨BitVec.sshiftRight' a.toBitVec (b.toBitVec.smod 8)⟩⟩
+def Int8.shiftRight (a b : Int8) : Int8 := ⟨⟨BitVec.sshiftRight' a.toBitVec (mod b 8).toBitVec⟩⟩
 @[extern "lean_int8_complement"]
 def Int8.complement (a : Int8) : Int8 := ⟨⟨~~~a.toBitVec⟩⟩
 
@@ -160,429 +114,3 @@ instance (a b : Int8) : Decidable (a < b) := Int8.decLt a b
 instance (a b : Int8) : Decidable (a ≤ b) := Int8.decLe a b
 instance : Max Int8 := maxOfLe
 instance : Min Int8 := minOfLe
-
-/-- The size of type `Int16`, that is, `2^16 = 65536`. -/
-abbrev Int16.size : Nat := 65536
-
-/--
-Obtain the `BitVec` that contains the 2's complement representation of the `Int16`.
--/
-@[inline] def Int16.toBitVec (x : Int16) : BitVec 16 := x.toUInt16.toBitVec
-
-@[extern "lean_int16_of_int"]
-def Int16.ofInt (i : @& Int) : Int16 := ⟨⟨BitVec.ofInt 16 i⟩⟩
-@[extern "lean_int16_of_nat"]
-def Int16.ofNat (n : @& Nat) : Int16 := ⟨⟨BitVec.ofNat 16 n⟩⟩
-abbrev Int.toInt16 := Int16.ofInt
-abbrev Nat.toInt16 := Int16.ofNat
-@[extern "lean_int16_to_int"]
-def Int16.toInt (i : Int16) : Int := i.toBitVec.toInt
-/--
-This function has the same behavior as `Int.toNat` for negative numbers.
-If you want to obtain the 2's complement representation use `toBitVec`.
--/
-@[inline] def Int16.toNat (i : Int16) : Nat := i.toInt.toNat
-@[extern "lean_int16_to_int8"]
-def Int16.toInt8 (a : Int16) : Int8 := ⟨⟨a.toBitVec.signExtend 8⟩⟩
-@[extern "lean_int8_to_int16"]
-def Int8.toInt16 (a : Int8) : Int16 := ⟨⟨a.toBitVec.signExtend 16⟩⟩
-@[extern "lean_int16_neg"]
-def Int16.neg (i : Int16) : Int16 := ⟨⟨-i.toBitVec⟩⟩
-
-instance : ToString Int16 where
-  toString i := toString i.toInt
-
-instance : OfNat Int16 n := ⟨Int16.ofNat n⟩
-instance : Neg Int16 where
-  neg := Int16.neg
-
-@[extern "lean_int16_add"]
-def Int16.add (a b : Int16) : Int16 := ⟨⟨a.toBitVec + b.toBitVec⟩⟩
-@[extern "lean_int16_sub"]
-def Int16.sub (a b : Int16) : Int16 := ⟨⟨a.toBitVec - b.toBitVec⟩⟩
-@[extern "lean_int16_mul"]
-def Int16.mul (a b : Int16) : Int16 := ⟨⟨a.toBitVec * b.toBitVec⟩⟩
-@[extern "lean_int16_div"]
-def Int16.div (a b : Int16) : Int16 := ⟨⟨BitVec.sdiv a.toBitVec b.toBitVec⟩⟩
-@[extern "lean_int16_mod"]
-def Int16.mod (a b : Int16) : Int16 := ⟨⟨BitVec.srem a.toBitVec b.toBitVec⟩⟩
-@[extern "lean_int16_land"]
-def Int16.land (a b : Int16) : Int16 := ⟨⟨a.toBitVec &&& b.toBitVec⟩⟩
-@[extern "lean_int16_lor"]
-def Int16.lor (a b : Int16) : Int16 := ⟨⟨a.toBitVec ||| b.toBitVec⟩⟩
-@[extern "lean_int16_xor"]
-def Int16.xor (a b : Int16) : Int16 := ⟨⟨a.toBitVec ^^^ b.toBitVec⟩⟩
-@[extern "lean_int16_shift_left"]
-def Int16.shiftLeft (a b : Int16) : Int16 := ⟨⟨a.toBitVec <<< (b.toBitVec.smod 16)⟩⟩
-@[extern "lean_int16_shift_right"]
-def Int16.shiftRight (a b : Int16) : Int16 := ⟨⟨BitVec.sshiftRight' a.toBitVec (b.toBitVec.smod 16)⟩⟩
-@[extern "lean_int16_complement"]
-def Int16.complement (a : Int16) : Int16 := ⟨⟨~~~a.toBitVec⟩⟩
-
-@[extern "lean_int16_dec_eq"]
-def Int16.decEq (a b : Int16) : Decidable (a = b) :=
-  match a, b with
-  | ⟨n⟩, ⟨m⟩ =>
-    if h : n = m then
-      isTrue <| h ▸ rfl
-    else
-      isFalse (fun h' => Int16.noConfusion h' (fun h' => absurd h' h))
-
-def Int16.lt (a b : Int16) : Prop := a.toBitVec.slt b.toBitVec
-def Int16.le (a b : Int16) : Prop := a.toBitVec.sle b.toBitVec
-
-instance : Inhabited Int16 where
-  default := 0
-
-instance : Add Int16         := ⟨Int16.add⟩
-instance : Sub Int16         := ⟨Int16.sub⟩
-instance : Mul Int16         := ⟨Int16.mul⟩
-instance : Mod Int16         := ⟨Int16.mod⟩
-instance : Div Int16         := ⟨Int16.div⟩
-instance : LT Int16          := ⟨Int16.lt⟩
-instance : LE Int16          := ⟨Int16.le⟩
-instance : Complement Int16  := ⟨Int16.complement⟩
-instance : AndOp Int16       := ⟨Int16.land⟩
-instance : OrOp Int16        := ⟨Int16.lor⟩
-instance : Xor Int16         := ⟨Int16.xor⟩
-instance : ShiftLeft Int16   := ⟨Int16.shiftLeft⟩
-instance : ShiftRight Int16  := ⟨Int16.shiftRight⟩
-instance : DecidableEq Int16 := Int16.decEq
-
-@[extern "lean_int16_dec_lt"]
-def Int16.decLt (a b : Int16) : Decidable (a < b) :=
-  inferInstanceAs (Decidable (a.toBitVec.slt b.toBitVec))
-
-@[extern "lean_int16_dec_le"]
-def Int16.decLe (a b : Int16) : Decidable (a ≤ b) :=
-  inferInstanceAs (Decidable (a.toBitVec.sle b.toBitVec))
-
-instance (a b : Int16) : Decidable (a < b) := Int16.decLt a b
-instance (a b : Int16) : Decidable (a ≤ b) := Int16.decLe a b
-instance : Max Int16 := maxOfLe
-instance : Min Int16 := minOfLe
-
-/-- The size of type `Int32`, that is, `2^32 = 4294967296`. -/
-abbrev Int32.size : Nat := 4294967296
-
-/--
-Obtain the `BitVec` that contains the 2's complement representation of the `Int32`.
--/
-@[inline] def Int32.toBitVec (x : Int32) : BitVec 32 := x.toUInt32.toBitVec
-
-@[extern "lean_int32_of_int"]
-def Int32.ofInt (i : @& Int) : Int32 := ⟨⟨BitVec.ofInt 32 i⟩⟩
-@[extern "lean_int32_of_nat"]
-def Int32.ofNat (n : @& Nat) : Int32 := ⟨⟨BitVec.ofNat 32 n⟩⟩
-abbrev Int.toInt32 := Int32.ofInt
-abbrev Nat.toInt32 := Int32.ofNat
-@[extern "lean_int32_to_int"]
-def Int32.toInt (i : Int32) : Int := i.toBitVec.toInt
-/--
-This function has the same behavior as `Int.toNat` for negative numbers.
-If you want to obtain the 2's complement representation use `toBitVec`.
--/
-@[inline] def Int32.toNat (i : Int32) : Nat := i.toInt.toNat
-@[extern "lean_int32_to_int8"]
-def Int32.toInt8 (a : Int32) : Int8 := ⟨⟨a.toBitVec.signExtend 8⟩⟩
-@[extern "lean_int32_to_int16"]
-def Int32.toInt16 (a : Int32) : Int16 := ⟨⟨a.toBitVec.signExtend 16⟩⟩
-@[extern "lean_int8_to_int32"]
-def Int8.toInt32 (a : Int8) : Int32 := ⟨⟨a.toBitVec.signExtend 32⟩⟩
-@[extern "lean_int16_to_int32"]
-def Int16.toInt32 (a : Int16) : Int32 := ⟨⟨a.toBitVec.signExtend 32⟩⟩
-@[extern "lean_int32_neg"]
-def Int32.neg (i : Int32) : Int32 := ⟨⟨-i.toBitVec⟩⟩
-
-instance : ToString Int32 where
-  toString i := toString i.toInt
-
-instance : OfNat Int32 n := ⟨Int32.ofNat n⟩
-instance : Neg Int32 where
-  neg := Int32.neg
-
-@[extern "lean_int32_add"]
-def Int32.add (a b : Int32) : Int32 := ⟨⟨a.toBitVec + b.toBitVec⟩⟩
-@[extern "lean_int32_sub"]
-def Int32.sub (a b : Int32) : Int32 := ⟨⟨a.toBitVec - b.toBitVec⟩⟩
-@[extern "lean_int32_mul"]
-def Int32.mul (a b : Int32) : Int32 := ⟨⟨a.toBitVec * b.toBitVec⟩⟩
-@[extern "lean_int32_div"]
-def Int32.div (a b : Int32) : Int32 := ⟨⟨BitVec.sdiv a.toBitVec b.toBitVec⟩⟩
-@[extern "lean_int32_mod"]
-def Int32.mod (a b : Int32) : Int32 := ⟨⟨BitVec.srem a.toBitVec b.toBitVec⟩⟩
-@[extern "lean_int32_land"]
-def Int32.land (a b : Int32) : Int32 := ⟨⟨a.toBitVec &&& b.toBitVec⟩⟩
-@[extern "lean_int32_lor"]
-def Int32.lor (a b : Int32) : Int32 := ⟨⟨a.toBitVec ||| b.toBitVec⟩⟩
-@[extern "lean_int32_xor"]
-def Int32.xor (a b : Int32) : Int32 := ⟨⟨a.toBitVec ^^^ b.toBitVec⟩⟩
-@[extern "lean_int32_shift_left"]
-def Int32.shiftLeft (a b : Int32) : Int32 := ⟨⟨a.toBitVec <<< (b.toBitVec.smod 32)⟩⟩
-@[extern "lean_int32_shift_right"]
-def Int32.shiftRight (a b : Int32) : Int32 := ⟨⟨BitVec.sshiftRight' a.toBitVec (b.toBitVec.smod 32)⟩⟩
-@[extern "lean_int32_complement"]
-def Int32.complement (a : Int32) : Int32 := ⟨⟨~~~a.toBitVec⟩⟩
-
-@[extern "lean_int32_dec_eq"]
-def Int32.decEq (a b : Int32) : Decidable (a = b) :=
-  match a, b with
-  | ⟨n⟩, ⟨m⟩ =>
-    if h : n = m then
-      isTrue <| h ▸ rfl
-    else
-      isFalse (fun h' => Int32.noConfusion h' (fun h' => absurd h' h))
-
-def Int32.lt (a b : Int32) : Prop := a.toBitVec.slt b.toBitVec
-def Int32.le (a b : Int32) : Prop := a.toBitVec.sle b.toBitVec
-
-instance : Inhabited Int32 where
-  default := 0
-
-instance : Add Int32         := ⟨Int32.add⟩
-instance : Sub Int32         := ⟨Int32.sub⟩
-instance : Mul Int32         := ⟨Int32.mul⟩
-instance : Mod Int32         := ⟨Int32.mod⟩
-instance : Div Int32         := ⟨Int32.div⟩
-instance : LT Int32          := ⟨Int32.lt⟩
-instance : LE Int32          := ⟨Int32.le⟩
-instance : Complement Int32  := ⟨Int32.complement⟩
-instance : AndOp Int32       := ⟨Int32.land⟩
-instance : OrOp Int32        := ⟨Int32.lor⟩
-instance : Xor Int32         := ⟨Int32.xor⟩
-instance : ShiftLeft Int32   := ⟨Int32.shiftLeft⟩
-instance : ShiftRight Int32  := ⟨Int32.shiftRight⟩
-instance : DecidableEq Int32 := Int32.decEq
-
-@[extern "lean_int32_dec_lt"]
-def Int32.decLt (a b : Int32) : Decidable (a < b) :=
-  inferInstanceAs (Decidable (a.toBitVec.slt b.toBitVec))
-
-@[extern "lean_int32_dec_le"]
-def Int32.decLe (a b : Int32) : Decidable (a ≤ b) :=
-  inferInstanceAs (Decidable (a.toBitVec.sle b.toBitVec))
-
-instance (a b : Int32) : Decidable (a < b) := Int32.decLt a b
-instance (a b : Int32) : Decidable (a ≤ b) := Int32.decLe a b
-instance : Max Int32 := maxOfLe
-instance : Min Int32 := minOfLe
-
-/-- The size of type `Int64`, that is, `2^64 = 18446744073709551616`. -/
-abbrev Int64.size : Nat := 18446744073709551616
-
-/--
-Obtain the `BitVec` that contains the 2's complement representation of the `Int64`.
--/
-@[inline] def Int64.toBitVec (x : Int64) : BitVec 64 := x.toUInt64.toBitVec
-
-@[extern "lean_int64_of_int"]
-def Int64.ofInt (i : @& Int) : Int64 := ⟨⟨BitVec.ofInt 64 i⟩⟩
-@[extern "lean_int64_of_nat"]
-def Int64.ofNat (n : @& Nat) : Int64 := ⟨⟨BitVec.ofNat 64 n⟩⟩
-abbrev Int.toInt64 := Int64.ofInt
-abbrev Nat.toInt64 := Int64.ofNat
-@[extern "lean_int64_to_int_sint"]
-def Int64.toInt (i : Int64) : Int := i.toBitVec.toInt
-/--
-This function has the same behavior as `Int.toNat` for negative numbers.
-If you want to obtain the 2's complement representation use `toBitVec`.
--/
-@[inline] def Int64.toNat (i : Int64) : Nat := i.toInt.toNat
-@[extern "lean_int64_to_int8"]
-def Int64.toInt8 (a : Int64) : Int8 := ⟨⟨a.toBitVec.signExtend 8⟩⟩
-@[extern "lean_int64_to_int16"]
-def Int64.toInt16 (a : Int64) : Int16 := ⟨⟨a.toBitVec.signExtend 16⟩⟩
-@[extern "lean_int64_to_int32"]
-def Int64.toInt32 (a : Int64) : Int32 := ⟨⟨a.toBitVec.signExtend 32⟩⟩
-@[extern "lean_int8_to_int64"]
-def Int8.toInt64 (a : Int8) : Int64 := ⟨⟨a.toBitVec.signExtend 64⟩⟩
-@[extern "lean_int16_to_int64"]
-def Int16.toInt64 (a : Int16) : Int64 := ⟨⟨a.toBitVec.signExtend 64⟩⟩
-@[extern "lean_int32_to_int64"]
-def Int32.toInt64 (a : Int32) : Int64 := ⟨⟨a.toBitVec.signExtend 64⟩⟩
-@[extern "lean_int64_neg"]
-def Int64.neg (i : Int64) : Int64 := ⟨⟨-i.toBitVec⟩⟩
-
-instance : ToString Int64 where
-  toString i := toString i.toInt
-
-instance : OfNat Int64 n := ⟨Int64.ofNat n⟩
-instance : Neg Int64 where
-  neg := Int64.neg
-
-@[extern "lean_int64_add"]
-def Int64.add (a b : Int64) : Int64 := ⟨⟨a.toBitVec + b.toBitVec⟩⟩
-@[extern "lean_int64_sub"]
-def Int64.sub (a b : Int64) : Int64 := ⟨⟨a.toBitVec - b.toBitVec⟩⟩
-@[extern "lean_int64_mul"]
-def Int64.mul (a b : Int64) : Int64 := ⟨⟨a.toBitVec * b.toBitVec⟩⟩
-@[extern "lean_int64_div"]
-def Int64.div (a b : Int64) : Int64 := ⟨⟨BitVec.sdiv a.toBitVec b.toBitVec⟩⟩
-@[extern "lean_int64_mod"]
-def Int64.mod (a b : Int64) : Int64 := ⟨⟨BitVec.srem a.toBitVec b.toBitVec⟩⟩
-@[extern "lean_int64_land"]
-def Int64.land (a b : Int64) : Int64 := ⟨⟨a.toBitVec &&& b.toBitVec⟩⟩
-@[extern "lean_int64_lor"]
-def Int64.lor (a b : Int64) : Int64 := ⟨⟨a.toBitVec ||| b.toBitVec⟩⟩
-@[extern "lean_int64_xor"]
-def Int64.xor (a b : Int64) : Int64 := ⟨⟨a.toBitVec ^^^ b.toBitVec⟩⟩
-@[extern "lean_int64_shift_left"]
-def Int64.shiftLeft (a b : Int64) : Int64 := ⟨⟨a.toBitVec <<< (b.toBitVec.smod 64)⟩⟩
-@[extern "lean_int64_shift_right"]
-def Int64.shiftRight (a b : Int64) : Int64 := ⟨⟨BitVec.sshiftRight' a.toBitVec (b.toBitVec.smod 64)⟩⟩
-@[extern "lean_int64_complement"]
-def Int64.complement (a : Int64) : Int64 := ⟨⟨~~~a.toBitVec⟩⟩
-
-@[extern "lean_int64_dec_eq"]
-def Int64.decEq (a b : Int64) : Decidable (a = b) :=
-  match a, b with
-  | ⟨n⟩, ⟨m⟩ =>
-    if h : n = m then
-      isTrue <| h ▸ rfl
-    else
-      isFalse (fun h' => Int64.noConfusion h' (fun h' => absurd h' h))
-
-def Int64.lt (a b : Int64) : Prop := a.toBitVec.slt b.toBitVec
-def Int64.le (a b : Int64) : Prop := a.toBitVec.sle b.toBitVec
-
-instance : Inhabited Int64 where
-  default := 0
-
-instance : Add Int64         := ⟨Int64.add⟩
-instance : Sub Int64         := ⟨Int64.sub⟩
-instance : Mul Int64         := ⟨Int64.mul⟩
-instance : Mod Int64         := ⟨Int64.mod⟩
-instance : Div Int64         := ⟨Int64.div⟩
-instance : LT Int64          := ⟨Int64.lt⟩
-instance : LE Int64          := ⟨Int64.le⟩
-instance : Complement Int64  := ⟨Int64.complement⟩
-instance : AndOp Int64       := ⟨Int64.land⟩
-instance : OrOp Int64        := ⟨Int64.lor⟩
-instance : Xor Int64         := ⟨Int64.xor⟩
-instance : ShiftLeft Int64   := ⟨Int64.shiftLeft⟩
-instance : ShiftRight Int64  := ⟨Int64.shiftRight⟩
-instance : DecidableEq Int64 := Int64.decEq
-
-@[extern "lean_int64_dec_lt"]
-def Int64.decLt (a b : Int64) : Decidable (a < b) :=
-  inferInstanceAs (Decidable (a.toBitVec.slt b.toBitVec))
-
-@[extern "lean_int64_dec_le"]
-def Int64.decLe (a b : Int64) : Decidable (a ≤ b) :=
-  inferInstanceAs (Decidable (a.toBitVec.sle b.toBitVec))
-
-instance (a b : Int64) : Decidable (a < b) := Int64.decLt a b
-instance (a b : Int64) : Decidable (a ≤ b) := Int64.decLe a b
-instance : Max Int64 := maxOfLe
-instance : Min Int64 := minOfLe
-
-/-- The size of type `ISize`, that is, `2^System.Platform.numBits`. -/
-abbrev ISize.size : Nat := 2^System.Platform.numBits
-
-/--
-Obtain the `BitVec` that contains the 2's complement representation of the `ISize`.
--/
-@[inline] def ISize.toBitVec (x : ISize) : BitVec System.Platform.numBits := x.toUSize.toBitVec
-
-@[extern "lean_isize_of_int"]
-def ISize.ofInt (i : @& Int) : ISize := ⟨⟨BitVec.ofInt System.Platform.numBits i⟩⟩
-@[extern "lean_isize_of_nat"]
-def ISize.ofNat (n : @& Nat) : ISize := ⟨⟨BitVec.ofNat System.Platform.numBits n⟩⟩
-abbrev Int.toISize := ISize.ofInt
-abbrev Nat.toISize := ISize.ofNat
-@[extern "lean_isize_to_int"]
-def ISize.toInt (i : ISize) : Int := i.toBitVec.toInt
-/--
-This function has the same behavior as `Int.toNat` for negative numbers.
-If you want to obtain the 2's complement representation use `toBitVec`.
--/
-@[inline] def ISize.toNat (i : ISize) : Nat := i.toInt.toNat
-@[extern "lean_isize_to_int32"]
-def ISize.toInt32 (a : ISize) : Int32 := ⟨⟨a.toBitVec.signExtend 32⟩⟩
-/--
-Upcast `ISize` to `Int64`. This function is losless as `ISize` is either `Int32` or `Int64`.
--/
-@[extern "lean_isize_to_int64"]
-def ISize.toInt64 (a : ISize) : Int64 := ⟨⟨a.toBitVec.signExtend 64⟩⟩
-/--
-Upcast `Int32` to `ISize`. This function is losless as `ISize` is either `Int32` or `Int64`.
--/
-@[extern "lean_int32_to_isize"]
-def Int32.toISize (a : Int32) : ISize := ⟨⟨a.toBitVec.signExtend System.Platform.numBits⟩⟩
-@[extern "lean_int64_to_isize"]
-def Int64.toISize (a : Int64) : ISize := ⟨⟨a.toBitVec.signExtend System.Platform.numBits⟩⟩
-@[extern "lean_isize_neg"]
-def ISize.neg (i : ISize) : ISize := ⟨⟨-i.toBitVec⟩⟩
-
-instance : ToString ISize where
-  toString i := toString i.toInt
-
-instance : OfNat ISize n := ⟨ISize.ofNat n⟩
-instance : Neg ISize where
-  neg := ISize.neg
-
-@[extern "lean_isize_add"]
-def ISize.add (a b : ISize) : ISize := ⟨⟨a.toBitVec + b.toBitVec⟩⟩
-@[extern "lean_isize_sub"]
-def ISize.sub (a b : ISize) : ISize := ⟨⟨a.toBitVec - b.toBitVec⟩⟩
-@[extern "lean_isize_mul"]
-def ISize.mul (a b : ISize) : ISize := ⟨⟨a.toBitVec * b.toBitVec⟩⟩
-@[extern "lean_isize_div"]
-def ISize.div (a b : ISize) : ISize := ⟨⟨BitVec.sdiv a.toBitVec b.toBitVec⟩⟩
-@[extern "lean_isize_mod"]
-def ISize.mod (a b : ISize) : ISize := ⟨⟨BitVec.srem a.toBitVec b.toBitVec⟩⟩
-@[extern "lean_isize_land"]
-def ISize.land (a b : ISize) : ISize := ⟨⟨a.toBitVec &&& b.toBitVec⟩⟩
-@[extern "lean_isize_lor"]
-def ISize.lor (a b : ISize) : ISize := ⟨⟨a.toBitVec ||| b.toBitVec⟩⟩
-@[extern "lean_isize_xor"]
-def ISize.xor (a b : ISize) : ISize := ⟨⟨a.toBitVec ^^^ b.toBitVec⟩⟩
-@[extern "lean_isize_shift_left"]
-def ISize.shiftLeft (a b : ISize) : ISize := ⟨⟨a.toBitVec <<< (b.toBitVec.smod System.Platform.numBits)⟩⟩
-@[extern "lean_isize_shift_right"]
-def ISize.shiftRight (a b : ISize) : ISize := ⟨⟨BitVec.sshiftRight' a.toBitVec (b.toBitVec.smod System.Platform.numBits)⟩⟩
-@[extern "lean_isize_complement"]
-def ISize.complement (a : ISize) : ISize := ⟨⟨~~~a.toBitVec⟩⟩
-
-@[extern "lean_isize_dec_eq"]
-def ISize.decEq (a b : ISize) : Decidable (a = b) :=
-  match a, b with
-  | ⟨n⟩, ⟨m⟩ =>
-    if h : n = m then
-      isTrue <| h ▸ rfl
-    else
-      isFalse (fun h' => ISize.noConfusion h' (fun h' => absurd h' h))
-
-def ISize.lt (a b : ISize) : Prop := a.toBitVec.slt b.toBitVec
-def ISize.le (a b : ISize) : Prop := a.toBitVec.sle b.toBitVec
-
-instance : Inhabited ISize where
-  default := 0
-
-instance : Add ISize         := ⟨ISize.add⟩
-instance : Sub ISize         := ⟨ISize.sub⟩
-instance : Mul ISize         := ⟨ISize.mul⟩
-instance : Mod ISize         := ⟨ISize.mod⟩
-instance : Div ISize         := ⟨ISize.div⟩
-instance : LT ISize          := ⟨ISize.lt⟩
-instance : LE ISize          := ⟨ISize.le⟩
-instance : Complement ISize  := ⟨ISize.complement⟩
-instance : AndOp ISize       := ⟨ISize.land⟩
-instance : OrOp ISize        := ⟨ISize.lor⟩
-instance : Xor ISize         := ⟨ISize.xor⟩
-instance : ShiftLeft ISize   := ⟨ISize.shiftLeft⟩
-instance : ShiftRight ISize  := ⟨ISize.shiftRight⟩
-instance : DecidableEq ISize := ISize.decEq
-
-@[extern "lean_isize_dec_lt"]
-def ISize.decLt (a b : ISize) : Decidable (a < b) :=
-  inferInstanceAs (Decidable (a.toBitVec.slt b.toBitVec))
-
-@[extern "lean_isize_dec_le"]
-def ISize.decLe (a b : ISize) : Decidable (a ≤ b) :=
-  inferInstanceAs (Decidable (a.toBitVec.sle b.toBitVec))
-
-instance (a b : ISize) : Decidable (a < b) := ISize.decLt a b
-instance (a b : ISize) : Decidable (a ≤ b) := ISize.decLe a b
-instance : Max ISize := maxOfLe
-instance : Min ISize := minOfLe

src/Init/Data/Sum/Lemmas.lean

@@ -17,11 +17,11 @@ open Function
 
 namespace Sum
 
-protected theorem «forall» {p : α ⊕ β → Prop} :
+@[simp] protected theorem «forall» {p : α ⊕ β → Prop} :
     (∀ x, p x) ↔ (∀ a, p (inl a)) ∧ ∀ b, p (inr b) :=
   ⟨fun h => ⟨fun _ => h _, fun _ => h _⟩, fun ⟨h₁, h₂⟩ => Sum.rec h₁ h₂⟩
 
-protected theorem «exists» {p : α ⊕ β → Prop} :
+@[simp] protected theorem «exists» {p : α ⊕ β → Prop} :
     (∃ x, p x) ↔ (∃ a, p (inl a)) ∨ ∃ b, p (inr b) :=
   ⟨ fun
     | ⟨inl a, h⟩ => Or.inl ⟨a, h⟩
@@ -116,7 +116,7 @@ theorem comp_elim (f : γ → δ) (g : α → γ) (h : β → γ) :
 
 theorem elim_eq_iff {u u' : α → γ} {v v' : β → γ} :
     Sum.elim u v = Sum.elim u' v' ↔ u = u' ∧ v = v' := by
-  simp [funext_iff, Sum.forall]
+  simp [funext_iff]
 
 /-! ### `Sum.map` -/
 

src/Init/Data/UInt/Basic.lean

@@ -19,8 +19,8 @@ def UInt8.mul (a b : UInt8) : UInt8 := ⟨a.toBitVec * b.toBitVec⟩
 def UInt8.div (a b : UInt8) : UInt8 := ⟨BitVec.udiv a.toBitVec b.toBitVec⟩
 @[extern "lean_uint8_mod"]
 def UInt8.mod (a b : UInt8) : UInt8 := ⟨BitVec.umod a.toBitVec b.toBitVec⟩
-@[deprecated UInt8.mod (since := "2024-09-23")]
-def UInt8.modn (a : UInt8) (n : Nat) : UInt8 := ⟨Fin.modn a.val n⟩
+@[extern "lean_uint8_modn", deprecated UInt8.mod (since := "2024-09-23")]
+def UInt8.modn (a : UInt8) (n : @& Nat) : UInt8 := ⟨Fin.modn a.val n⟩
 @[extern "lean_uint8_land"]
 def UInt8.land (a b : UInt8) : UInt8 := ⟨a.toBitVec &&& b.toBitVec⟩
 @[extern "lean_uint8_lor"]
@@ -79,8 +79,8 @@ def UInt16.mul (a b : UInt16) : UInt16 := ⟨a.toBitVec * b.toBitVec⟩
 def UInt16.div (a b : UInt16) : UInt16 := ⟨BitVec.udiv a.toBitVec b.toBitVec⟩
 @[extern "lean_uint16_mod"]
 def UInt16.mod (a b : UInt16) : UInt16 := ⟨BitVec.umod a.toBitVec b.toBitVec⟩
-@[deprecated UInt16.mod (since := "2024-09-23")]
-def UInt16.modn (a : UInt16) (n : Nat) : UInt16 := ⟨Fin.modn a.val n⟩
+@[extern "lean_uint16_modn", deprecated UInt16.mod (since := "2024-09-23")]
+def UInt16.modn (a : UInt16) (n : @& Nat) : UInt16 := ⟨Fin.modn a.val n⟩
 @[extern "lean_uint16_land"]
 def UInt16.land (a b : UInt16) : UInt16 := ⟨a.toBitVec &&& b.toBitVec⟩
 @[extern "lean_uint16_lor"]
@@ -141,8 +141,8 @@ def UInt32.mul (a b : UInt32) : UInt32 := ⟨a.toBitVec * b.toBitVec⟩
 def UInt32.div (a b : UInt32) : UInt32 := ⟨BitVec.udiv a.toBitVec b.toBitVec⟩
 @[extern "lean_uint32_mod"]
 def UInt32.mod (a b : UInt32) : UInt32 := ⟨BitVec.umod a.toBitVec b.toBitVec⟩
-@[deprecated UInt32.mod (since := "2024-09-23")]
-def UInt32.modn (a : UInt32) (n : Nat) : UInt32 := ⟨Fin.modn a.val n⟩
+@[extern "lean_uint32_modn", deprecated UInt32.mod (since := "2024-09-23")]
+def UInt32.modn (a : UInt32) (n : @& Nat) : UInt32 := ⟨Fin.modn a.val n⟩
 @[extern "lean_uint32_land"]
 def UInt32.land (a b : UInt32) : UInt32 := ⟨a.toBitVec &&& b.toBitVec⟩
 @[extern "lean_uint32_lor"]
@@ -184,8 +184,8 @@ def UInt64.mul (a b : UInt64) : UInt64 := ⟨a.toBitVec * b.toBitVec⟩
 def UInt64.div (a b : UInt64) : UInt64 := ⟨BitVec.udiv a.toBitVec b.toBitVec⟩
 @[extern "lean_uint64_mod"]
 def UInt64.mod (a b : UInt64) : UInt64 := ⟨BitVec.umod a.toBitVec b.toBitVec⟩
-@[deprecated UInt64.mod (since := "2024-09-23")]
-def UInt64.modn (a : UInt64) (n : Nat) : UInt64 := ⟨Fin.modn a.val n⟩
+@[extern "lean_uint64_modn", deprecated UInt64.mod (since := "2024-09-23")]
+def UInt64.modn (a : UInt64) (n : @& Nat) : UInt64 := ⟨Fin.modn a.val n⟩
 @[extern "lean_uint64_land"]
 def UInt64.land (a b : UInt64) : UInt64 := ⟨a.toBitVec &&& b.toBitVec⟩
 @[extern "lean_uint64_lor"]
@@ -243,8 +243,8 @@ def USize.mul (a b : USize) : USize := ⟨a.toBitVec * b.toBitVec⟩
 def USize.div (a b : USize) : USize := ⟨a.toBitVec / b.toBitVec⟩
 @[extern "lean_usize_mod"]
 def USize.mod (a b : USize) : USize := ⟨a.toBitVec % b.toBitVec⟩
-@[deprecated USize.mod (since := "2024-09-23")]
-def USize.modn (a : USize) (n : Nat) : USize := ⟨Fin.modn a.val n⟩
+@[extern "lean_usize_modn", deprecated USize.mod (since := "2024-09-23")]
+def USize.modn (a : USize) (n : @& Nat) : USize := ⟨Fin.modn a.val n⟩
 @[extern "lean_usize_land"]
 def USize.land (a b : USize) : USize := ⟨a.toBitVec &&& b.toBitVec⟩
 @[extern "lean_usize_lor"]

src/Init/GetElem.lean

@@ -211,13 +211,10 @@ instance : GetElem (List α) Nat α fun as i => i < as.length where
   | _ :: _, 0, _ => .head ..
   | _ :: l, _+1, _ => .tail _ (getElem_mem (l := l) ..)
 
-theorem getElem_cons_drop_succ_eq_drop {as : List α} {i : Nat} (h : i < as.length) :
-    as[i] :: as.drop (i+1) = as.drop i :=
+theorem get_drop_eq_drop (as : List α) (i : Nat) (h : i < as.length) : as[i] :: as.drop (i+1) = as.drop i :=
   match as, i with
   | _::_, 0   => rfl
-  | _::_, i+1 => getElem_cons_drop_succ_eq_drop (i := i) _
-
-@[deprecated (since := "2024-11-05")] abbrev get_drop_eq_drop := @getElem_cons_drop_succ_eq_drop
+  | _::_, i+1 => get_drop_eq_drop _ i _
 
 end List
 

src/Init/Meta.lean

@@ -629,9 +629,6 @@ def mkStrLit (val : String) (info := SourceInfo.none) : StrLit :=
 def mkNumLit (val : String) (info := SourceInfo.none) : NumLit :=
   mkLit numLitKind val info
 
-def mkNatLit (val : Nat) (info := SourceInfo.none) : NumLit :=
-  mkLit numLitKind (toString val) info
-
 def mkScientificLit (val : String) (info := SourceInfo.none) : TSyntax scientificLitKind :=
   mkLit scientificLitKind val info
 
@@ -1412,87 +1409,64 @@ namespace Parser
 
 namespace Tactic
 
-/--
-Extracts the items from a tactic configuration,
-either a `Lean.Parser.Tactic.optConfig`, `Lean.Parser.Tactic.config`, or these wrapped in null nodes.
--/
-partial def getConfigItems (c : Syntax) : TSyntaxArray ``configItem :=
-  if c.isOfKind nullKind then
-    c.getArgs.flatMap getConfigItems
-  else
-    match c with
-    | `(optConfig| $items:configItem*) => items
-    | `(config| (config := $_)) => #[⟨c⟩] -- handled by mkConfigItemViews
-    | _ => #[]
-
-def mkOptConfig (items : TSyntaxArray ``configItem) : TSyntax ``optConfig :=
-  ⟨Syntax.node1 .none ``optConfig (mkNullNode items)⟩
-
-/--
-Appends two tactic configurations.
-The configurations can be `Lean.Parser.Tactic.optConfig`, `Lean.Parser.Tactic.config`,
-or these wrapped in null nodes (for example because the syntax is `(config)?`).
--/
-def appendConfig (cfg cfg' : Syntax) : TSyntax ``optConfig :=
-  mkOptConfig <| getConfigItems cfg ++ getConfigItems cfg'
-
-/-- `erw [rules]` is a shorthand for `rw (transparency := .default) [rules]`.
+/-- `erw [rules]` is a shorthand for `rw (config := { transparency := .default }) [rules]`.
 This does rewriting up to unfolding of regular definitions (by comparison to regular `rw`
 which only unfolds `@[reducible]` definitions). -/
-macro "erw" c:optConfig s:rwRuleSeq loc:(location)? : tactic => do
-  `(tactic| rw $[$(getConfigItems c)]* (transparency := .default) $s:rwRuleSeq $(loc)?)
+macro "erw" s:rwRuleSeq loc:(location)? : tactic =>
+  `(tactic| rw (config := { transparency := .default }) $s $(loc)?)
 
 syntax simpAllKind := atomic(" (" &"all") " := " &"true" ")"
 syntax dsimpKind   := atomic(" (" &"dsimp") " := " &"true" ")"
 
 macro (name := declareSimpLikeTactic) doc?:(docComment)?
     "declare_simp_like_tactic" opt:((simpAllKind <|> dsimpKind)?)
-    ppSpace tacName:ident ppSpace tacToken:str ppSpace cfg:optConfig : command => do
+    ppSpace tacName:ident ppSpace tacToken:str ppSpace updateCfg:term : command => do
   let (kind, tkn, stx) ←
     if opt.raw.isNone then
-      pure (← `(``simp), ← `("simp"), ← `($[$doc?:docComment]? syntax (name := $tacName) $tacToken:str optConfig (discharger)? (&" only")? (" [" (simpStar <|> simpErase <|> simpLemma),* "]")? (location)? : tactic))
+      pure (← `(``simp), ← `("simp"), ← `($[$doc?:docComment]? syntax (name := $tacName) $tacToken:str (config)? (discharger)? (&" only")? (" [" (simpStar <|> simpErase <|> simpLemma),* "]")? (location)? : tactic))
     else if opt.raw[0].getKind == ``simpAllKind then
-      pure (← `(``simpAll), ← `("simp_all"), ← `($[$doc?:docComment]? syntax (name := $tacName) $tacToken:str optConfig (discharger)? (&" only")? (" [" (simpErase <|> simpLemma),* "]")? : tactic))
+      pure (← `(``simpAll), ← `("simp_all"), ← `($[$doc?:docComment]? syntax (name := $tacName) $tacToken:str (config)? (discharger)? (&" only")? (" [" (simpErase <|> simpLemma),* "]")? : tactic))
     else
-      pure (← `(``dsimp), ← `("dsimp"), ← `($[$doc?:docComment]? syntax (name := $tacName) $tacToken:str optConfig (discharger)? (&" only")? (" [" (simpErase <|> simpLemma),* "]")? (location)? : tactic))
+      pure (← `(``dsimp), ← `("dsimp"), ← `($[$doc?:docComment]? syntax (name := $tacName) $tacToken:str (config)? (discharger)? (&" only")? (" [" (simpErase <|> simpLemma),* "]")? (location)? : tactic))
   `($stx:command
     @[macro $tacName] def expandSimp : Macro := fun s => do
-      let cfg ← `(optConfig| $cfg)
+      let c ← match s[1][0] with
+        | `(config| (config := $$c)) => `(config| (config := $updateCfg $$c))
+        | _ => `(config| (config := $updateCfg {}))
       let s := s.setKind $kind
       let s := s.setArg 0 (mkAtomFrom s[0] $tkn (canonical := true))
-      let s := s.setArg 1 (appendConfig s[1] cfg)
-      let s := s.mkSynthetic
-      return s)
+      let r := s.setArg 1 (mkNullNode #[c])
+      return r)
 
 /-- `simp!` is shorthand for `simp` with `autoUnfold := true`.
 This will rewrite with all equation lemmas, which can be used to
 partially evaluate many definitions. -/
-declare_simp_like_tactic simpAutoUnfold "simp! " (autoUnfold := true)
+declare_simp_like_tactic simpAutoUnfold "simp! " fun (c : Lean.Meta.Simp.Config) => { c with autoUnfold := true }
 
 /-- `simp_arith` is shorthand for `simp` with `arith := true` and `decide := true`.
 This enables the use of normalization by linear arithmetic. -/
-declare_simp_like_tactic simpArith "simp_arith " (arith := true) (decide := true)
+declare_simp_like_tactic simpArith "simp_arith " fun (c : Lean.Meta.Simp.Config) => { c with arith := true, decide := true }
 
 /-- `simp_arith!` is shorthand for `simp_arith` with `autoUnfold := true`.
 This will rewrite with all equation lemmas, which can be used to
 partially evaluate many definitions. -/
-declare_simp_like_tactic simpArithAutoUnfold "simp_arith! " (arith := true) (autoUnfold := true) (decide := true)
+declare_simp_like_tactic simpArithAutoUnfold "simp_arith! " fun (c : Lean.Meta.Simp.Config) => { c with arith := true, autoUnfold := true, decide := true }
 
 /-- `simp_all!` is shorthand for `simp_all` with `autoUnfold := true`.
 This will rewrite with all equation lemmas, which can be used to
 partially evaluate many definitions. -/
-declare_simp_like_tactic (all := true) simpAllAutoUnfold "simp_all! " (autoUnfold := true)
+declare_simp_like_tactic (all := true) simpAllAutoUnfold "simp_all! " fun (c : Lean.Meta.Simp.ConfigCtx) => { c with autoUnfold := true }
 
 /-- `simp_all_arith` combines the effects of `simp_all` and `simp_arith`. -/
-declare_simp_like_tactic (all := true) simpAllArith "simp_all_arith " (arith := true) (decide := true)
+declare_simp_like_tactic (all := true) simpAllArith "simp_all_arith " fun (c : Lean.Meta.Simp.ConfigCtx) => { c with arith := true, decide := true }
 
 /-- `simp_all_arith!` combines the effects of `simp_all`, `simp_arith` and `simp!`. -/
-declare_simp_like_tactic (all := true) simpAllArithAutoUnfold "simp_all_arith! " (arith := true) (autoUnfold := true) (decide := true)
+declare_simp_like_tactic (all := true) simpAllArithAutoUnfold "simp_all_arith! " fun (c : Lean.Meta.Simp.ConfigCtx) => { c with arith := true, autoUnfold := true, decide := true }
 
 /-- `dsimp!` is shorthand for `dsimp` with `autoUnfold := true`.
 This will rewrite with all equation lemmas, which can be used to
 partially evaluate many definitions. -/
-declare_simp_like_tactic (dsimp := true) dsimpAutoUnfold "dsimp! " (autoUnfold := true)
+declare_simp_like_tactic (dsimp := true) dsimpAutoUnfold "dsimp! " fun (c : Lean.Meta.DSimp.Config) => { c with autoUnfold := true }
 
 end Tactic
 

src/Init/PropLemmas.lean

@@ -643,11 +643,11 @@ theorem decide_ite (u : Prop) [du : Decidable u] (p q : Prop)
     (@ite _ p h q (decide p)) = (decide p && q) := by
   split <;> simp_all
 
-@[deprecated ite_then_decide_self (since := "2024-08-29")]
+@[deprecated ite_then_decide_self]
 theorem ite_true_decide_same (p : Prop) [Decidable p] (b : Bool) :
   (if p then decide p else b) = (decide p || b) := ite_then_decide_self p b
 
-@[deprecated ite_false_decide_same (since := "2024-08-29")]
+@[deprecated ite_false_decide_same]
 theorem ite_false_decide_same (p : Prop) [Decidable p] (b : Bool) :
   (if p then b else decide p) = (decide p && b) := ite_else_decide_self p b
 

src/Init/SimpLemmas.lean

@@ -54,13 +54,6 @@ theorem forall_prop_domain_congr {p₁ p₂ : Prop} {q₁ : p₁ → Prop} {q₂
     : (∀ a : p₁, q₁ a) = (∀ a : p₂, q₂ a) := by
   subst h₁; simp [← h₂]
 
-theorem forall_prop_congr_dom {p₁ p₂ : Prop} (h : p₁ = p₂) (q : p₁ → Prop) :
-    (∀ a : p₁, q a) = (∀ a : p₂, q (h.substr a)) :=
-  h ▸ rfl
-
-theorem pi_congr {α : Sort u} {β β' : α → Sort v} (h : ∀ a, β a = β' a) : (∀ a, β a) = ∀ a, β' a :=
-  (funext h : β = β') ▸ rfl
-
 theorem let_congr {α : Sort u} {β : Sort v} {a a' : α} {b b' : α → β}
     (h₁ : a = a') (h₂ : ∀ x, b x = b' x) : (let x := a; b x) = (let x := a'; b' x) :=
   h₁ ▸ (funext h₂ : b = b') ▸ rfl

src/Init/Tactics.lean

@@ -272,20 +272,12 @@ macro nextTk:"next " args:binderIdent* arrowTk:" => " tac:tacticSeq : tactic =>
   -- Limit ref variability for incrementality; see Note [Incremental Macros]
   withRef arrowTk `(tactic| case%$nextTk _ $args* =>%$arrowTk $tac)
 
-/--
-`all_goals tac` runs `tac` on each goal, concatenating the resulting goals.
-If the tactic fails on any goal, the entire `all_goals` tactic fails.
-
-See also `any_goals tac`.
--/
+/-- `all_goals tac` runs `tac` on each goal, concatenating the resulting goals, if any. -/
 syntax (name := allGoals) "all_goals " tacticSeq : tactic
 
 /--
-`any_goals tac` applies the tactic `tac` to every goal,
-concating the resulting goals for successful tactic applications.
-If the tactic fails on all of the goals, the entire `any_goals` tactic fails.
-
-This tactic is like `all_goals try tac` except that it fails if none of the applications of `tac` succeeds.
+`any_goals tac` applies the tactic `tac` to every goal, and succeeds if at
+least one application succeeds.
 -/
 syntax (name := anyGoals) "any_goals " tacticSeq : tactic
 
@@ -425,27 +417,7 @@ It synthesizes a value of any target type by typeclass inference.
 -/
 macro "infer_instance" : tactic => `(tactic| exact inferInstance)
 
-/--
-`+opt` is short for `(opt := true)`. It sets the `opt` configuration option to `true`.
--/
-syntax posConfigItem := "+" noWs ident
-/--
-`-opt` is short for `(opt := false)`. It sets the `opt` configuration option to `false`.
--/
-syntax negConfigItem := "-" noWs ident
-/--
-`(opt := val)` sets the `opt` configuration option to `val`.
-
-As a special case, `(config := ...)` sets the entire configuration.
--/
-syntax valConfigItem := atomic(" (" notFollowedBy(&"discharger" <|> &"disch") (ident <|> &"config")) " := " withoutPosition(term) ")"
-/-- A configuration item for a tactic configuration. -/
-syntax configItem := posConfigItem <|> negConfigItem <|> valConfigItem
-
-/-- Configuration options for tactics. -/
-syntax optConfig := (colGt configItem)*
-
-/-- Optional configuration option for tactics. (Deprecated. Replace `(config)?` with `optConfig`.) -/
+/-- Optional configuration option for tactics -/
 syntax config := atomic(" (" &"config") " := " withoutPosition(term) ")"
 
 /-- The `*` location refers to all hypotheses and the goal. -/
@@ -502,25 +474,25 @@ This provides a convenient way to unfold `e`.
   list of hypotheses in the local context. In the latter case, a turnstile `⊢` or `|-`
   can also be used, to signify the target of the goal.
 
-Using `rw (occs := .pos L) [e]`,
+Using `rw (config := {occs := .pos L}) [e]`,
 where `L : List Nat`, you can control which "occurrences" are rewritten.
 (This option applies to each rule, so usually this will only be used with a single rule.)
 Occurrences count from `1`.
 At each allowed occurrence, arguments of the rewrite rule `e` may be instantiated,
 restricting which later rewrites can be found.
 (Disallowed occurrences do not result in instantiation.)
-`(occs := .neg L)` allows skipping specified occurrences.
+`{occs := .neg L}` allows skipping specified occurrences.
 -/
-syntax (name := rewriteSeq) "rewrite" optConfig rwRuleSeq (location)? : tactic
+syntax (name := rewriteSeq) "rewrite" (config)? rwRuleSeq (location)? : tactic
 
 /--
 `rw` is like `rewrite`, but also tries to close the goal by "cheap" (reducible) `rfl` afterwards.
 -/
-macro (name := rwSeq) "rw " c:optConfig s:rwRuleSeq l:(location)? : tactic =>
+macro (name := rwSeq) "rw " c:(config)? s:rwRuleSeq l:(location)? : tactic =>
   match s with
   | `(rwRuleSeq| [$rs,*]%$rbrak) =>
     -- We show the `rfl` state on `]`
-    `(tactic| (rewrite $c [$rs,*] $(l)?; with_annotate_state $rbrak (try (with_reducible rfl))))
+    `(tactic| (rewrite $(c)? [$rs,*] $(l)?; with_annotate_state $rbrak (try (with_reducible rfl))))
   | _ => Macro.throwUnsupported
 
 /-- `rwa` is short-hand for `rw; assumption`. -/
@@ -589,14 +561,14 @@ non-dependent hypotheses. It has many variants:
 - `simp [*] at *` simplifies target and all (propositional) hypotheses using the
   other hypotheses.
 -/
-syntax (name := simp) "simp" optConfig (discharger)? (&" only")?
+syntax (name := simp) "simp" (config)? (discharger)? (&" only")?
   (" [" withoutPosition((simpStar <|> simpErase <|> simpLemma),*,?) "]")? (location)? : tactic
 /--
 `simp_all` is a stronger version of `simp [*] at *` where the hypotheses and target
 are simplified multiple times until no simplification is applicable.
 Only non-dependent propositional hypotheses are considered.
 -/
-syntax (name := simpAll) "simp_all" optConfig (discharger)? (&" only")?
+syntax (name := simpAll) "simp_all" (config)? (discharger)? (&" only")?
   (" [" withoutPosition((simpErase <|> simpLemma),*,?) "]")? : tactic
 
 /--
@@ -604,7 +576,7 @@ The `dsimp` tactic is the definitional simplifier. It is similar to `simp` but o
 applies theorems that hold by reflexivity. Thus, the result is guaranteed to be
 definitionally equal to the input.
 -/
-syntax (name := dsimp) "dsimp" optConfig (discharger)? (&" only")?
+syntax (name := dsimp) "dsimp" (config)? (discharger)? (&" only")?
   (" [" withoutPosition((simpErase <|> simpLemma),*,?) "]")? (location)? : tactic
 
 /--
@@ -626,7 +598,7 @@ def dsimpArg := simpErase.binary `orelse simpLemma
 syntax dsimpArgs := " [" dsimpArg,* "]"
 
 /-- The common arguments of `simp?` and `simp?!`. -/
-syntax simpTraceArgsRest := optConfig (discharger)? (&" only")? (simpArgs)? (ppSpace location)?
+syntax simpTraceArgsRest := (config)? (discharger)? (&" only")? (simpArgs)? (ppSpace location)?
 
 /--
 `simp?` takes the same arguments as `simp`, but reports an equivalent call to `simp only`
@@ -645,7 +617,7 @@ syntax (name := simpTrace) "simp?" "!"? simpTraceArgsRest : tactic
 macro tk:"simp?!" rest:simpTraceArgsRest : tactic => `(tactic| simp?%$tk ! $rest)
 
 /-- The common arguments of `simp_all?` and `simp_all?!`. -/
-syntax simpAllTraceArgsRest := optConfig (discharger)? (&" only")? (dsimpArgs)?
+syntax simpAllTraceArgsRest := (config)? (discharger)? (&" only")? (dsimpArgs)?
 
 @[inherit_doc simpTrace]
 syntax (name := simpAllTrace) "simp_all?" "!"? simpAllTraceArgsRest : tactic
@@ -654,7 +626,7 @@ syntax (name := simpAllTrace) "simp_all?" "!"? simpAllTraceArgsRest : tactic
 macro tk:"simp_all?!" rest:simpAllTraceArgsRest : tactic => `(tactic| simp_all?%$tk ! $rest)
 
 /-- The common arguments of `dsimp?` and `dsimp?!`. -/
-syntax dsimpTraceArgsRest := optConfig (&" only")? (dsimpArgs)? (ppSpace location)?
+syntax dsimpTraceArgsRest := (config)? (&" only")? (dsimpArgs)? (ppSpace location)?
 
 @[inherit_doc simpTrace]
 syntax (name := dsimpTrace) "dsimp?" "!"? dsimpTraceArgsRest : tactic
@@ -663,7 +635,7 @@ syntax (name := dsimpTrace) "dsimp?" "!"? dsimpTraceArgsRest : tactic
 macro tk:"dsimp?!" rest:dsimpTraceArgsRest : tactic => `(tactic| dsimp?%$tk ! $rest)
 
 /-- The arguments to the `simpa` family tactics. -/
-syntax simpaArgsRest := optConfig (discharger)? &" only "? (simpArgs)? (" using " term)?
+syntax simpaArgsRest := (config)? (discharger)? &" only "? (simpArgs)? (" using " term)?
 
 /--
 This is a "finishing" tactic modification of `simp`. It has two forms.
@@ -1176,7 +1148,8 @@ a natural subtraction appearing in a hypothesis, and try again.
 
 The options
 ```
-omega +splitDisjunctions +splitNatSub +splitNatAbs +splitMinMax
+omega (config :=
+  { splitDisjunctions := true, splitNatSub := true, splitNatAbs := true, splitMinMax := true })
 ```
 can be used to:
 * `splitDisjunctions`: split any disjunctions found in the context,
@@ -1186,7 +1159,7 @@ can be used to:
 * `splitMinMax`: for each occurrence of `min a b`, split on `min a b = a ∨ min a b = b`
 Currently, all of these are on by default.
 -/
-syntax (name := omega) "omega" optConfig : tactic
+syntax (name := omega) "omega" (config)? : tactic
 
 /--
 `bv_omega` is `omega` with an additional preprocessor that turns statements about `BitVec` into statements about `Nat`.
@@ -1299,7 +1272,7 @@ example (a b : Nat)
 
 See also `norm_cast`.
 -/
-syntax (name := pushCast) "push_cast" optConfig (discharger)? (&" only")?
+syntax (name := pushCast) "push_cast" (config)? (discharger)? (&" only")?
   (" [" (simpStar <|> simpErase <|> simpLemma),* "]")? (location)? : tactic
 
 /--
@@ -1375,7 +1348,7 @@ See also the doc-comment for `Lean.Meta.Tactic.Backtrack.BacktrackConfig` for th
 Both `apply_assumption` and `apply_rules` are implemented via these hooks.
 -/
 syntax (name := solveByElim)
-  "solve_by_elim" "*"? optConfig (&" only")? (args)? (using_)? : tactic
+  "solve_by_elim" "*"? (config)? (&" only")? (args)? (using_)? : tactic
 
 /--
 `apply_assumption` looks for an assumption of the form `... → ∀ _, ... → head`
@@ -1398,7 +1371,7 @@ You can pass a further configuration via the syntax `apply_rules (config := {...
 The options supported are the same as for `solve_by_elim` (and include all the options for `apply`).
 -/
 syntax (name := applyAssumption)
-  "apply_assumption" optConfig (&" only")? (args)? (using_)? : tactic
+  "apply_assumption" (config)? (&" only")? (args)? (using_)? : tactic
 
 /--
 `apply_rules [l₁, l₂, ...]` tries to solve the main goal by iteratively
@@ -1423,7 +1396,7 @@ You can bound the iteration depth using the syntax `apply_rules (config := {maxD
 Unlike `solve_by_elim`, `apply_rules` does not perform backtracking, and greedily applies
 a lemma from the list until it gets stuck.
 -/
-syntax (name := applyRules) "apply_rules" optConfig (&" only")? (args)? (using_)? : tactic
+syntax (name := applyRules) "apply_rules" (config)? (&" only")? (args)? (using_)? : tactic
 end SolveByElim
 
 /--
@@ -1622,7 +1595,7 @@ where `i < arr.size` is in the context) and `simp_arith` and `omega`
 syntax "get_elem_tactic_trivial" : tactic
 
 macro_rules | `(tactic| get_elem_tactic_trivial) => `(tactic| omega)
-macro_rules | `(tactic| get_elem_tactic_trivial) => `(tactic| simp +arith; done)
+macro_rules | `(tactic| get_elem_tactic_trivial) => `(tactic| simp (config := { arith := true }); done)
 macro_rules | `(tactic| get_elem_tactic_trivial) => `(tactic| trivial)
 
 /--

src/Init/TacticsExtra.lean

@@ -70,11 +70,11 @@ macro_rules
 /--
 Rewrites with the given rules, normalizing casts prior to each step.
 -/
-syntax "rw_mod_cast" optConfig rwRuleSeq (location)? : tactic
+syntax "rw_mod_cast" (config)? rwRuleSeq (location)? : tactic
 macro_rules
-  | `(tactic| rw_mod_cast $cfg:optConfig [$rules,*] $[$loc]?) => do
+  | `(tactic| rw_mod_cast $[$config]? [$rules,*] $[$loc]?) => do
     let tacs ← rules.getElems.mapM fun rule =>
-      `(tactic| (norm_cast at *; rw $cfg [$rule] $[$loc]?))
+      `(tactic| (norm_cast at *; rw $[$config]? [$rule] $[$loc]?))
     `(tactic| ($[$tacs]*))
 
 /--

src/Init/WFTactics.lean

@@ -16,14 +16,15 @@ user, and this tactic should no longer be necessary. Calls to `simp_wf` can be r
 by plain calls to `simp`.
 -/
 macro "simp_wf" : tactic =>
-  `(tactic| try simp +unfoldPartialApp +zetaDelta [invImage, InvImage, Prod.lex, sizeOfWFRel, measure, Nat.lt_wfRel, WellFoundedRelation.rel])
+  `(tactic| try simp (config := { unfoldPartialApp := true, zetaDelta := true }) [invImage, InvImage, Prod.lex, sizeOfWFRel, measure, Nat.lt_wfRel, WellFoundedRelation.rel])
 
 /--
 This tactic is used internally by lean before presenting the proof obligations from a well-founded
 definition to the user via `decreasing_by`. It is not necessary to use this tactic manually.
 -/
 macro "clean_wf" : tactic =>
-  `(tactic| simp +unfoldPartialApp +zetaDelta -failIfUnchanged
+  `(tactic| simp
+     (config := { unfoldPartialApp := true, zetaDelta := true, failIfUnchanged := false })
      only [invImage, InvImage, Prod.lex, sizeOfWFRel, measure, Nat.lt_wfRel,
            WellFoundedRelation.rel, sizeOf_nat, reduceCtorEq])
 
@@ -36,7 +37,7 @@ macro_rules | `(tactic| decreasing_trivial) => `(tactic| linarith)
 -/
 syntax "decreasing_trivial" : tactic
 
-macro_rules | `(tactic| decreasing_trivial) => `(tactic| (simp +arith -failIfUnchanged) <;> done)
+macro_rules | `(tactic| decreasing_trivial) => `(tactic| (simp (config := { arith := true, failIfUnchanged := false })) <;> done)
 macro_rules | `(tactic| decreasing_trivial) => `(tactic| omega)
 macro_rules | `(tactic| decreasing_trivial) => `(tactic| assumption)
 

src/Lean/Compiler/IR/ElimDeadVars.lean

@@ -13,7 +13,7 @@ partial def reshapeWithoutDead (bs : Array FnBody) (term : FnBody) : FnBody :=
   let rec reshape (bs : Array FnBody) (b : FnBody) (used : IndexSet) :=
     if bs.isEmpty then b
     else
-      let curr := bs.back!
+      let curr := bs.back
       let bs   := bs.pop
       let keep (_ : Unit) :=
         let used := curr.collectFreeIndices used

src/Lean/Compiler/IR/EmitLLVM.lean

@@ -1075,7 +1075,7 @@ def emitSetTag (builder : LLVM.Builder llvmctx) (x : VarId) (i : Nat) : M llvmct
 def ensureHasDefault' (alts : Array Alt) : Array Alt :=
   if alts.any Alt.isDefault then alts
   else
-    let last := alts.back!
+    let last := alts.back
     let alts := alts.pop
     alts.push (Alt.default last.body)
 

src/Lean/Compiler/IR/ExpandResetReuse.lean

@@ -56,7 +56,7 @@ partial def eraseProjIncForAux (y : VarId) (bs : Array FnBody) (mask : Mask) (ke
   let keepInstr (b : FnBody) := eraseProjIncForAux y bs.pop mask (keep.push b)
   if bs.size < 2 then done ()
   else
-    let b := bs.back!
+    let b := bs.back
     match b with
     | .vdecl _ _ (.sproj _ _ _) _ => keepInstr b
     | .vdecl _ _ (.uproj _ _) _   => keepInstr b

src/Lean/Compiler/IR/PushProj.lean

@@ -13,7 +13,7 @@ namespace Lean.IR
 partial def pushProjs (bs : Array FnBody) (alts : Array Alt) (altsF : Array IndexSet) (ctx : Array FnBody) (ctxF : IndexSet) : Array FnBody × Array Alt :=
   if bs.isEmpty then (ctx.reverse, alts)
   else
-    let b    := bs.back!
+    let b    := bs.back
     let bs   := bs.pop
     let done (_ : Unit) := (bs.push b ++ ctx.reverse, alts)
     let skip (_ : Unit) := pushProjs bs alts altsF (ctx.push b) (b.collectFreeIndices ctxF)

src/Lean/Compiler/IR/SimpCase.lean

@@ -13,8 +13,8 @@ def ensureHasDefault (alts : Array Alt) : Array Alt :=
   if alts.any Alt.isDefault then alts
   else if alts.size < 2 then alts
   else
-    let last := alts.back!
-    let alts := alts.pop
+    let last := alts.back;
+    let alts := alts.pop;
     alts.push (Alt.default last.body)
 
 private def getOccsOf (alts : Array Alt) (i : Nat) : Nat := Id.run do

src/Lean/Compiler/LCNF/InferType.lean

@@ -168,12 +168,13 @@ mutual
       /- TODO: after we erase universe variables, we can just extract a better type using just `structName` and `idx`. -/
       return erasedExpr
     else
-      matchConstStructure structType.getAppFn failed fun structVal structLvls ctorVal =>
-        let structTypeArgs := structType.getAppArgs
-        if structVal.numParams + structVal.numIndices != structTypeArgs.size then
+      matchConstStruct structType.getAppFn failed fun structVal structLvls ctorVal =>
+        let n := structVal.numParams
+        let structParams := structType.getAppArgs
+        if n != structParams.size then
           failed ()
         else do
-          let mut ctorType ← inferAppType (mkAppN (mkConst ctorVal.name structLvls) structTypeArgs[:structVal.numParams])
+          let mut ctorType ← inferAppType (mkAppN (mkConst ctorVal.name structLvls) structParams)
           for _ in [:idx] do
             match ctorType with
             | .forallE _ _ body _ =>

src/Lean/Data/HashMap.lean

@@ -271,11 +271,11 @@ def ofListWith (l : List (α × β)) (f : β → β → β) : HashMap α β :=
         | none   => m.insert p.fst p.snd
         | some v => m.insert p.fst $ f v p.snd)
 
-attribute [deprecated Std.HashMap (since := "2024-08-08")] HashMap
-attribute [deprecated Std.HashMap.Raw (since := "2024-08-08")] HashMapImp
-attribute [deprecated Std.HashMap.Raw.empty (since := "2024-08-08")] mkHashMapImp
-attribute [deprecated Std.HashMap.empty (since := "2024-08-08")] mkHashMap
-attribute [deprecated Std.HashMap.empty (since := "2024-08-08")] HashMap.empty
-attribute [deprecated Std.HashMap.ofList (since := "2024-08-08")] HashMap.ofList
+attribute [deprecated Std.HashMap] HashMap
+attribute [deprecated Std.HashMap.Raw] HashMapImp
+attribute [deprecated Std.HashMap.Raw.empty] mkHashMapImp
+attribute [deprecated Std.HashMap.empty] mkHashMap
+attribute [deprecated Std.HashMap.empty] HashMap.empty
+attribute [deprecated Std.HashMap.ofList] HashMap.ofList
 
 end Lean.HashMap

src/Lean/Data/HashSet.lean

@@ -219,8 +219,8 @@ def merge {α : Type u} [BEq α] [Hashable α] (s t : HashSet α) : HashSet α :
   t.fold (init := s) fun s a => s.insert a
   -- We don't use `insertMany` here because it gives weird universes.
 
-attribute [deprecated Std.HashSet (since := "2024-08-08")] HashSet
-attribute [deprecated Std.HashSet.Raw (since := "2024-08-08")] HashSetImp
-attribute [deprecated Std.HashSet.Raw.empty (since := "2024-08-08")] mkHashSetImp
-attribute [deprecated Std.HashSet.empty (since := "2024-08-08")] mkHashSet
-attribute [deprecated Std.HashSet.empty (since := "2024-08-08")] HashSet.empty
+attribute [deprecated Std.HashSet] HashSet
+attribute [deprecated Std.HashSet.Raw] HashSetImp
+attribute [deprecated Std.HashSet.Raw.empty] mkHashSetImp
+attribute [deprecated Std.HashSet.empty] mkHashSet
+attribute [deprecated Std.HashSet.empty] HashSet.empty

src/Lean/Data/KVMap.lean

@@ -177,7 +177,7 @@ def updateSyntax (m : KVMap) (k : Name) (f : Syntax → Syntax) : KVMap :=
 
 @[inline] protected def forIn.{w, w'} {δ : Type w} {m : Type w → Type w'} [Monad m]
   (kv : KVMap) (init : δ) (f : Name × DataValue → δ → m (ForInStep δ)) : m δ :=
-  forIn kv.entries init f
+  kv.entries.forIn init f
 
 instance : ForIn m KVMap (Name × DataValue) where
   forIn := KVMap.forIn

src/Lean/Data/Lsp/Utf16.lean

@@ -70,7 +70,7 @@ private def lineStartPos (text : FileMap) (line : Nat) : String.Pos :=
   else if text.positions.isEmpty then
     0
   else
-    text.positions.back!
+    text.positions.back
 
 /-- Computes an UTF-8 offset into `text.source`
 from an LSP-style 0-indexed (ln, col) position. -/

src/Lean/Data/Position.lean

@@ -66,12 +66,12 @@ partial def ofString (s : String) : FileMap :=
       let i := s.next i
       if c == '\n' then loop i (line+1) (ps.push i)
       else loop i line ps
-  loop 0 1 #[0]
+  loop 0 1 (#[0])
 
 partial def toPosition (fmap : FileMap) (pos : String.Pos) : Position :=
   match fmap with
   | { source := str, positions := ps } =>
-    if ps.size >= 2 && pos <= ps.back! then
+    if ps.size >= 2 && pos <= ps.back then
       let rec toColumn (i : String.Pos) (c : Nat) : Nat :=
         if i == pos || str.atEnd i then c
         else toColumn (str.next i) (c+1)
@@ -84,14 +84,14 @@ partial def toPosition (fmap : FileMap) (pos : String.Pos) : Position :=
           if pos == posM then { line := fmap.getLine m, column := 0 }
           else if pos > posM then loop m e
           else loop b m
-      loop 0 (ps.size - 1)
+      loop 0 (ps.size -1)
     else if ps.isEmpty then
       ⟨0, 0⟩
     else
       -- Some systems like the delaborator use synthetic positions without an input file,
       -- which would violate `toPositionAux`'s invariant.
       -- Can also happen with EOF errors, which are not strictly inside the file.
-      ⟨fmap.getLastLine, (pos - ps.back!).byteIdx⟩
+      ⟨fmap.getLastLine, (pos - ps.back).byteIdx⟩
 
 /-- Convert a `Lean.Position` to a `String.Pos`. -/
 def ofPosition (text : FileMap) (pos : Position) : String.Pos :=
@@ -101,7 +101,7 @@ def ofPosition (text : FileMap) (pos : Position) : String.Pos :=
     else if text.positions.isEmpty then
       0
     else
-      text.positions.back!
+      text.positions.back
   String.Iterator.nextn ⟨text.source, colPos⟩ pos.column |>.pos
 
 /--

src/Lean/Data/RBMap.lean

@@ -298,14 +298,9 @@ instance : ForIn m (RBMap α β cmp) (α × β) where
   | ⟨leaf, _⟩ => true
   | _         => false
 
-/-- Returns a `List` of the key/value pairs in order. -/
 @[specialize] def toList : RBMap α β cmp → List (α × β)
   | ⟨t, _⟩ => t.revFold (fun ps k v => (k, v)::ps) []
 
-/-- Returns an `Array` of the key/value pairs in order. -/
-@[specialize] def toArray : RBMap α β cmp → Array (α × β)
-  | ⟨t, _⟩ => t.fold (fun ps k v => ps.push (k, v)) #[]
-
 /-- Returns the kv pair `(a,b)` such that `a ≤ k` for all keys in the RBMap. -/
 @[inline] protected def min : RBMap α β cmp → Option (α × β)
   | ⟨t, _⟩ =>

src/Lean/Data/Xml/Parser.lean

@@ -463,7 +463,7 @@ mutual
     let mut res := #[]
     for x in xs do
       if res.size > 0 then
-        match res.back!, x with
+        match res.back, x with
         | Content.Character x, Content.Character y => res := res.set! (res.size - 1) (Content.Character $ x ++ y)
         | _, x => res := res.push x
       else res := res.push x

src/Lean/Elab/App.lean

@@ -595,22 +595,6 @@ mutual
       elabAndAddNewArg argName arg
       main
     | _ =>
-      if (← read).ellipsis && (← readThe Term.Context).inPattern then
-        /-
-        In patterns, ellipsis should always be an implicit argument, even if it is an optparam or autoparam.
-        This prevents examples such as the one in #4555 from failing:
-        ```lean
-        match e with
-        | .internal .. => sorry
-        | .error .. => sorry
-        ```
-        The `internal` has an optparam (`| internal (id : InternalExceptionId) (extra : KVMap := {})`).
-
-        We may consider having ellipsis suppress optparams and autoparams in general.
-        We avoid doing so for now since it's possible to opt-out of them (for example with `.internal (extra := _) ..`)
-        but it's not possible to opt-in.
-        -/
-        return ← addImplicitArg argName
       let argType ← getArgExpectedType
       match (← read).explicit, argType.getOptParamDefault?, argType.getAutoParamTactic? with
       | false, some defVal, _  => addNewArg argName defVal; main
@@ -1151,29 +1135,24 @@ private def throwLValError (e : Expr) (eType : Expr) (msg : MessageData) : TermE
   throwError "{msg}{indentExpr e}\nhas type{indentExpr eType}"
 
 /--
-`findMethod? S fName` tries the following for each namespace `S'` in the resolution order for `S`:
-- If `env` contains `S' ++ fName`, returns `(S', S' ++ fName)`
-- Otherwise if `env` contains private name `prv` for `S' ++ fName`, returns `(S', prv)`
+`findMethod? env S fName`.
+- If `env` contains `S ++ fName`, return `(S, S++fName)`
+- Otherwise if `env` contains private name `prv` for `S ++ fName`, return `(S, prv)`, o
+- Otherwise for each parent structure `S'` of  `S`, we try `findMethod? env S' fname`
 -/
-private partial def findMethod? (structName fieldName : Name) : MetaM (Option (Name × Name)) := do
-  let env ← getEnv
-  let find? structName' : MetaM (Option (Name × Name)) := do
-    let fullName := structName' ++ fieldName
-    if env.contains fullName then
-      return some (structName', fullName)
+private partial def findMethod? (env : Environment) (structName fieldName : Name) : Option (Name × Name) :=
+  let fullName := structName ++ fieldName
+  match env.find? fullName with
+  | some _ => some (structName, fullName)
+  | none   =>
     let fullNamePrv := mkPrivateName env fullName
-    if env.contains fullNamePrv then
-      return some (structName', fullNamePrv)
-    return none
-  -- Optimization: the first element of the resolution order is `structName`,
-  -- so we can skip computing the resolution order in the common case
-  -- of the name resolving in the `structName` namespace.
-  find? structName <||> do
-    let resolutionOrder ← if isStructure env structName then getStructureResolutionOrder structName else pure #[structName]
-    for h : i in [1:resolutionOrder.size] do
-      if let some res ← find? resolutionOrder[i] then
-        return res
-    return none
+    match env.find? fullNamePrv with
+    | some _ => some (structName, fullNamePrv)
+    | none   =>
+      if isStructure env structName then
+        (getStructureSubobjects env structName).findSome? fun parentStructName => findMethod? env parentStructName fieldName
+      else
+        none
 
 /--
   Return `some (structName', fullName)` if `structName ++ fieldName` is an alias for `fullName`, and
@@ -1209,23 +1188,23 @@ private def resolveLValAux (e : Expr) (eType : Expr) (lval : LVal) : TermElabM L
     if idx == 0 then
       throwError "invalid projection, index must be greater than 0"
     let env ← getEnv
-    let failK _ := throwLValError e eType "invalid projection, structure expected"
-    matchConstStructure eType.getAppFn failK fun _ _ ctorVal => do
-      let numFields := ctorVal.numFields
-      if idx - 1 < numFields then
-        if isStructure env structName then
-          let fieldNames := getStructureFields env structName
-          return LValResolution.projFn structName structName fieldNames[idx - 1]!
-        else
-          /- `structName` was declared using `inductive` command.
-            So, we don't projection functions for it. Thus, we use `Expr.proj` -/
-          return LValResolution.projIdx structName (idx - 1)
+    unless isStructureLike env structName do
+      throwLValError e eType "invalid projection, structure expected"
+    let numFields := getStructureLikeNumFields env structName
+    if idx - 1 < numFields then
+      if isStructure env structName then
+        let fieldNames := getStructureFields env structName
+        return LValResolution.projFn structName structName fieldNames[idx - 1]!
       else
-        throwLValError e eType m!"invalid projection, structure has only {numFields} field(s)"
+        /- `structName` was declared using `inductive` command.
+           So, we don't projection functions for it. Thus, we use `Expr.proj` -/
+        return LValResolution.projIdx structName (idx - 1)
+    else
+      throwLValError e eType m!"invalid projection, structure has only {numFields} field(s)"
   | some structName, LVal.fieldName _ fieldName _ _ =>
     let env ← getEnv
     let searchEnv : Unit → TermElabM LValResolution := fun _ => do
-      if let some (baseStructName, fullName) ← findMethod? structName (.mkSimple fieldName) then
+      if let some (baseStructName, fullName) := findMethod? env structName (.mkSimple fieldName) then
         return LValResolution.const baseStructName structName fullName
       else if let some (structName', fullName) := findMethodAlias? env structName (.mkSimple fieldName) then
         return LValResolution.const structName' structName' fullName
@@ -1411,17 +1390,19 @@ private def elabAppLValsAux (namedArgs : Array NamedArg) (args : Array Arg) (exp
       loop f lvals
     | LValResolution.projFn baseStructName structName fieldName =>
       let f ← mkBaseProjections baseStructName structName f
-      let some info := getFieldInfo? (← getEnv) baseStructName fieldName | unreachable!
-      if isPrivateNameFromImportedModule (← getEnv) info.projFn then
-        throwError "field '{fieldName}' from structure '{structName}' is private"
-      let projFn ← mkConst info.projFn
-      let projFn ← addProjTermInfo lval.getRef projFn
-      if lvals.isEmpty then
-        let namedArgs ← addNamedArg namedArgs { name := `self, val := Arg.expr f, suppressDeps := true }
-        elabAppArgs projFn namedArgs args expectedType? explicit ellipsis
+      if let some info := getFieldInfo? (← getEnv) baseStructName fieldName then
+        if isPrivateNameFromImportedModule (← getEnv) info.projFn then
+          throwError "field '{fieldName}' from structure '{structName}' is private"
+        let projFn ← mkConst info.projFn
+        let projFn ← addProjTermInfo lval.getRef projFn
+        if lvals.isEmpty then
+          let namedArgs ← addNamedArg namedArgs { name := `self, val := Arg.expr f, suppressDeps := true }
+          elabAppArgs projFn namedArgs args expectedType? explicit ellipsis
+        else
+          let f ← elabAppArgs projFn #[{ name := `self, val := Arg.expr f, suppressDeps := true }] #[] (expectedType? := none) (explicit := false) (ellipsis := false)
+          loop f lvals
       else
-        let f ← elabAppArgs projFn #[{ name := `self, val := Arg.expr f, suppressDeps := true }] #[] (expectedType? := none) (explicit := false) (ellipsis := false)
-        loop f lvals
+        unreachable!
     | LValResolution.const baseStructName structName constName =>
       let f ← if baseStructName != structName then mkBaseProjections baseStructName structName f else pure f
       let projFn ← mkConst constName

src/Lean/Elab/Arg.lean

@@ -39,7 +39,7 @@ partial def expandArgs (args : Array Syntax) : MetaM (Array NamedArg × Array Ar
   let (args, ellipsis) :=
     if args.isEmpty then
       (args, false)
-    else if args.back!.isOfKind ``Lean.Parser.Term.ellipsis then
+    else if args.back.isOfKind ``Lean.Parser.Term.ellipsis then
       (args.pop, true)
     else
       (args, false)

src/Lean/Elab/BuiltinCommand.lean

@@ -424,87 +424,4 @@ def failIfSucceeds (x : CommandElabM Unit) : CommandElabM Unit := do
 @[builtin_command_elab Parser.Command.eoi] def elabEoi : CommandElab := fun _ =>
   return
 
-@[builtin_command_elab Parser.Command.where] def elabWhere : CommandElab := fun _ => do
-  let scope ← getScope
-  let mut msg : Array MessageData := #[]
-  -- Noncomputable
-  if scope.isNoncomputable then
-    msg := msg.push <| ← `(command| noncomputable section)
-  -- Namespace
-  if !scope.currNamespace.isAnonymous then
-    msg := msg.push <| ← `(command| namespace $(mkIdent scope.currNamespace))
-  -- Open namespaces
-  if let some openMsg ← describeOpenDecls scope.openDecls.reverse then
-    msg := msg.push openMsg
-  -- Universe levels
-  if !scope.levelNames.isEmpty then
-    let levels := scope.levelNames.reverse.map mkIdent
-    msg := msg.push <| ← `(command| universe $levels.toArray*)
-  -- Variables
-  if !scope.varDecls.isEmpty then
-    let varDecls : Array (TSyntax `Lean.Parser.Term.bracketedBinder) := scope.varDecls.map (⟨·.raw.unsetTrailing⟩)
-    msg := msg.push <| ← `(command| variable $varDecls*)
-  -- Included variables
-  if !scope.includedVars.isEmpty then
-    msg := msg.push <| ← `(command| include $(scope.includedVars.toArray.map (mkIdent ·.eraseMacroScopes))*)
-  -- Options
-  if let some optionsMsg ← describeOptions scope.opts then
-    msg := msg.push optionsMsg
-  if msg.isEmpty then
-    logInfo m!"-- In root namespace with initial scope"
-  else
-    logInfo <| MessageData.joinSep msg.toList "\n\n"
-where
-  /--
-  'Delaborate' open declarations.
-  Current limitations:
-  - does not check whether or not successive namespaces need `_root_`
-  - does not combine commands with `renaming` clauses into a single command
-  -/
-  describeOpenDecls (ds : List OpenDecl) : CommandElabM (Option MessageData) := do
-    let mut lines : Array MessageData := #[]
-    let mut simple : Array Name := #[]
-    let flush (lines : Array MessageData) (simple : Array Name) : CommandElabM (Array MessageData × Array Name) := do
-      if simple.isEmpty then
-        return (lines, simple)
-      else
-        return (lines.push <| ← `(command| open $(simple.map mkIdent)*), #[])
-    for d in ds do
-      match d with
-      | .explicit id decl =>
-        (lines, simple) ← flush lines simple
-        let ns := decl.getPrefix
-        let «from» := Name.mkSimple decl.getString!
-        lines := lines.push <| ← `(command| open $(mkIdent ns) renaming $(mkIdent «from») → $(mkIdent id))
-      | .simple ns ex =>
-        if ex == [] then
-          simple := simple.push ns
-        else
-          (lines, simple) ← flush lines simple
-          lines := lines.push <| ← `(command| open $(mkIdent ns) hiding $[$(ex.toArray.map mkIdent)]*)
-    (lines, _) ← flush lines simple
-    return if lines.isEmpty then none else MessageData.joinSep lines.toList "\n"
-
-  describeOptions (opts : Options) : CommandElabM (Option MessageData) := do
-    let mut lines : Array MessageData := #[]
-    let decls ← getOptionDecls
-    for (name, val) in opts do
-      let (isSet, isUnknown) :=
-        match decls.find? name with
-        | some decl => (decl.defValue != val, false)
-        | none      => (true, true)
-      if isSet then
-        let cmd : TSyntax `command ←
-          match val with
-          | .ofBool true  => `(set_option $(mkIdent name) true)
-          | .ofBool false => `(set_option $(mkIdent name) false)
-          | .ofString str => `(set_option $(mkIdent name) $(Syntax.mkStrLit str))
-          | .ofNat n      => `(set_option $(mkIdent name) $(Syntax.mkNatLit n))
-          | _             => `(set_option $(mkIdent name) 0 /- unrepresentable value -/)
-        if isUnknown then
-          lines := lines.push m!"-- {cmd} -- unknown option"
-        else
-          lines := lines.push cmd
-    return if lines.isEmpty then none else MessageData.joinSep lines.toList "\n"
-
 end Lean.Elab.Command

src/Lean/Elab/BuiltinEvalCommand.lean

@@ -137,7 +137,7 @@ private def mkFormat (e : Expr) : MetaM Expr := do
       if let .const name _ := (← whnf (← inferType e)).getAppFn then
         try
           trace[Elab.eval] "Attempting to derive a 'Repr' instance for '{.ofConstName name}'"
-          liftCommandElabM do applyDerivingHandlers ``Repr #[name]
+          liftCommandElabM do applyDerivingHandlers ``Repr #[name] none
           resetSynthInstanceCache
           return ← mkRepr e
         catch ex =>

src/Lean/Elab/BuiltinNotation.lean

@@ -226,7 +226,7 @@ partial def mkPairs (elems : Array Term) : MacroM Term :=
       loop i acc
     else
       pure acc
-  loop (elems.size - 1) elems.back!
+  loop (elems.size - 1) elems.back
 
 /-- Return syntax `PProd.mk elems[0] (PProd.mk elems[1] ... (PProd.mk elems[elems.size - 2] elems[elems.size - 1])))` -/
 partial def mkPPairs (elems : Array Term) : MacroM Term :=
@@ -238,7 +238,7 @@ partial def mkPPairs (elems : Array Term) : MacroM Term :=
       loop i acc
     else
       pure acc
-  loop (elems.size - 1) elems.back!
+  loop (elems.size - 1) elems.back
 
 /-- Return syntax `MProd.mk elems[0] (MProd.mk elems[1] ... (MProd.mk elems[elems.size - 2] elems[elems.size - 1])))` -/
 partial def mkMPairs (elems : Array Term) : MacroM Term :=
@@ -250,7 +250,7 @@ partial def mkMPairs (elems : Array Term) : MacroM Term :=
       loop i acc
     else
       pure acc
-  loop (elems.size - 1) elems.back!
+  loop (elems.size - 1) elems.back
 
 
 open Parser in

src/Lean/Elab/Calc.lean

@@ -136,7 +136,7 @@ def throwCalcFailure (steps : Array CalcStepView) (expectedType result : Expr) :
           but is expected to be{indentD m!"{elhs} : {← inferType elhs}"}"
         failed := true
       unless ← isDefEqGuarded rhs erhs do
-        logErrorAt steps.back!.term m!"\
+        logErrorAt steps.back.term m!"\
           invalid 'calc' step, right-hand side is{indentD m!"{rhs} : {← inferType rhs}"}\n\
           but is expected to be{indentD m!"{erhs} : {← inferType erhs}"}"
         failed := true

src/Lean/Elab/Deriving/Basic.lean

@@ -5,7 +5,6 @@ Authors: Leonardo de Moura, Wojciech Nawrocki
 -/
 prelude
 import Lean.Elab.Command
-import Lean.Elab.DeclarationRange
 
 namespace Lean.Elab
 open Command
@@ -56,17 +55,13 @@ def processDefDeriving (className : Name) (declName : Name) : TermElabM Bool :=
       safety      := info.safety
     }
     addInstance instName AttributeKind.global (eval_prio default)
-    addDeclarationRangesFromSyntax instName (← getRef)
     return true
   catch _ =>
     return false
 
 end Term
 
-def DerivingHandler := (typeNames : Array Name) → CommandElabM Bool
-
-/-- Deprecated - `DerivingHandler` no longer assumes arguments -/
-@[deprecated DerivingHandler (since := "2024-09-09")]
+def DerivingHandler := (typeNames : Array Name) → (args? : Option (TSyntax ``Parser.Term.structInst)) → CommandElabM Bool
 def DerivingHandlerNoArgs := (typeNames : Array Name) → CommandElabM Bool
 
 builtin_initialize derivingHandlersRef : IO.Ref (NameMap (List DerivingHandler)) ← IO.mkRef {}
@@ -76,21 +71,25 @@ as well as the syntax of a `with` argument, if present.
 
 For example, `deriving instance Foo with fooArgs for Bar, Baz` invokes
 ``fooHandler #[`Bar, `Baz] `(fooArgs)``. -/
-def registerDerivingHandler (className : Name) (handler : DerivingHandler) : IO Unit := do
+def registerDerivingHandlerWithArgs (className : Name) (handler : DerivingHandler) : IO Unit := do
   unless (← initializing) do
     throw (IO.userError "failed to register deriving handler, it can only be registered during initialization")
   derivingHandlersRef.modify fun m => match m.find? className with
     | some handlers => m.insert className (handler :: handlers)
     | none => m.insert className [handler]
 
+/-- Like `registerBuiltinDerivingHandlerWithArgs` but ignoring any `with` argument. -/
+def registerDerivingHandler (className : Name) (handler : DerivingHandlerNoArgs) : IO Unit := do
+  registerDerivingHandlerWithArgs className fun typeNames _ => handler typeNames
+
 def defaultHandler (className : Name) (typeNames : Array Name) : CommandElabM Unit := do
   throwError "default handlers have not been implemented yet, class: '{className}' types: {typeNames}"
 
-def applyDerivingHandlers (className : Name) (typeNames : Array Name) : CommandElabM Unit := do
+def applyDerivingHandlers (className : Name) (typeNames : Array Name) (args? : Option (TSyntax ``Parser.Term.structInst)) : CommandElabM Unit := do
   match (← derivingHandlersRef.get).find? className with
   | some handlers =>
     for handler in handlers do
-      if (← handler typeNames) then
+      if (← handler typeNames args?) then
         return ()
     defaultHandler className typeNames
   | none => defaultHandler className typeNames
@@ -100,16 +99,16 @@ private def tryApplyDefHandler (className : Name) (declName : Name) : CommandEla
     Term.processDefDeriving className declName
 
 @[builtin_command_elab «deriving»] def elabDeriving : CommandElab
-  | `(deriving instance $[$classes],* for $[$declNames],*) => do
+  | `(deriving instance $[$classes $[with $argss?]?],* for $[$declNames],*) => do
      let declNames ← liftCoreM <| declNames.mapM realizeGlobalConstNoOverloadWithInfo
-     for cls in classes do
+     for cls in classes, args? in argss? do
        try
          let className ← liftCoreM <| realizeGlobalConstNoOverloadWithInfo cls
          withRef cls do
-           if declNames.size == 1 then
+           if declNames.size == 1 && args?.isNone then
              if (← tryApplyDefHandler className declNames[0]!) then
                return ()
-           applyDerivingHandlers className declNames
+           applyDerivingHandlers className declNames args?
        catch ex =>
          logException ex
   | _ => throwUnsupportedSyntax
@@ -117,19 +116,20 @@ private def tryApplyDefHandler (className : Name) (declName : Name) : CommandEla
 structure DerivingClassView where
   ref : Syntax
   className : Name
+  args? : Option (TSyntax ``Parser.Term.structInst)
 
 def getOptDerivingClasses (optDeriving : Syntax) : CoreM (Array DerivingClassView) := do
   match optDeriving with
-  | `(Parser.Command.optDeriving| deriving $[$classes],*) =>
+  | `(Parser.Command.optDeriving| deriving $[$classes $[with $argss?]?],*) =>
     let mut ret := #[]
-    for cls in classes do
+    for cls in classes, args? in argss? do
       let className ← realizeGlobalConstNoOverloadWithInfo cls
-      ret := ret.push { ref := cls, className := className }
+      ret := ret.push { ref := cls, className := className, args? }
     return ret
   | _ => return #[]
 
 def DerivingClassView.applyHandlers (view : DerivingClassView) (declNames : Array Name) : CommandElabM Unit :=
-  withRef view.ref do applyDerivingHandlers view.className declNames
+  withRef view.ref do applyDerivingHandlers view.className declNames view.args?
 
 builtin_initialize
   registerTraceClass `Elab.Deriving

src/Lean/Elab/Do.lean

@@ -801,7 +801,7 @@ private def mkTuple (elems : Array Syntax) : MacroM Syntax := do
   else if elems.size == 1 then
     return elems[0]!
   else
-    elems.extract 0 (elems.size - 1) |>.foldrM (init := elems.back!) fun elem tuple =>
+    elems.extract 0 (elems.size - 1) |>.foldrM (init := elems.back) fun elem tuple =>
       ``(MProd.mk $elem $tuple)
 
 /-- Return `some action` if `doElem` is a `doExpr <action>`-/

src/Lean/Elab/Level.lean

@@ -60,11 +60,11 @@ partial def elabLevel (stx : Syntax) : LevelElabM Level := withRef stx do
     elabLevel (stx.getArg 1)
   else if kind == ``Lean.Parser.Level.max then
     let args := stx.getArg 1 |>.getArgs
-    args[:args.size - 1].foldrM (init := ← elabLevel args.back!) fun stx lvl =>
+    args[:args.size - 1].foldrM (init := ← elabLevel args.back) fun stx lvl =>
       return mkLevelMax' (← elabLevel stx) lvl
   else if kind == ``Lean.Parser.Level.imax then
     let args := stx.getArg 1 |>.getArgs
-    args[:args.size - 1].foldrM (init := ← elabLevel args.back!) fun stx lvl =>
+    args[:args.size - 1].foldrM (init := ← elabLevel args.back) fun stx lvl =>
       return mkLevelIMax' (← elabLevel stx) lvl
   else if kind == ``Lean.Parser.Level.hole then
     mkFreshLevelMVar

src/Lean/Elab/Match.lean

@@ -957,7 +957,7 @@ where
     let mut s : CollectFVars.State := {}
     for discr in discrs do
       s := collectFVars s (← instantiateMVars (← inferType discr))
-    let (indicesFVar, indicesNonFVar) := indices.partition Expr.isFVar
+    let (indicesFVar, indicesNonFVar) := indices.split Expr.isFVar
     let indicesFVar := indicesFVar.map Expr.fvarId!
     let mut toAdd := #[]
     for fvarId in s.fvarSet.toList do

src/Lean/Elab/PreDefinition/Structural/IndGroupInfo.lean

@@ -105,6 +105,6 @@ def IndGroupInst.nestedTypeFormers (igi : IndGroupInst) : MetaM (Array Expr) :=
   auxMotives.mapM fun motive =>
     forallTelescopeReducing motive fun xs _ => do
       assert! xs.size > 0
-      mkForallFVars xs.pop (← inferType xs.back!)
+      mkForallFVars xs.pop (← inferType xs.back)
 
 end Lean.Elab.Structural

src/Lean/Elab/PreDefinition/TerminationArgument.lean

@@ -118,7 +118,7 @@ def TerminationArgument.delab (arity : Nat) (extraParams : Nat) (termArg : Termi
         Array.map (fun (i : Ident) => if stxBody.raw.hasIdent i.getId then i else hole) vars
       -- drop trailing underscores
       let mut vars := vars
-      while ! vars.isEmpty && vars.back!.raw.isOfKind ``hole do vars := vars.pop
+      while ! vars.isEmpty && vars.back.raw.isOfKind ``hole do vars := vars.pop
       if termArg.structural then
         if vars.isEmpty then
           `(terminationBy|termination_by structural $stxBody)

src/Lean/Elab/Quotation.lean

@@ -190,7 +190,7 @@ private partial def quoteSyntax : Syntax → TermElabM Term
                 | $[some $ids:ident],* => $(quote inner)
                 | $[_%$ids],*          => Array.empty)
             | _ =>
-              let arr ← ids[:ids.size-1].foldrM (fun id arr => `(Array.zip $id:ident $arr)) ids.back!
+              let arr ← ids[:ids.size-1].foldrM (fun id arr => `(Array.zip $id:ident $arr)) ids.back
               `(Array.map (fun $(← mkTuple ids) => $(inner[0]!)) $arr)
           let arr ← if k == `sepBy then
             `(mkSepArray $arr $(getSepStxFromSplice arg))

src/Lean/Elab/Structure.lean

@@ -22,12 +22,7 @@ namespace Lean.Elab.Command
 
 register_builtin_option structureDiamondWarning : Bool := {
   defValue := false
-  descr    := "if true, enable warnings when a structure has diamond inheritance"
-}
-
-register_builtin_option structure.strictResolutionOrder : Bool := {
-  defValue := false
-  descr := "if true, require a strict resolution order for structures"
+  descr    := "enable/disable warning messages for structure diamonds"
 }
 
 open Meta
@@ -811,16 +806,9 @@ private def mkAuxConstructions (declName : Name) : TermElabM Unit := do
   let hasEq   := env.contains ``Eq
   let hasHEq  := env.contains ``HEq
   let hasUnit := env.contains ``PUnit
-  let hasProd := env.contains ``Prod
   mkRecOn declName
   if hasUnit then mkCasesOn declName
   if hasUnit && hasEq && hasHEq then mkNoConfusion declName
-  let ival ← getConstInfoInduct declName
-  if ival.isRec then
-    if hasUnit && hasProd then mkBelow declName
-    if hasUnit && hasProd then mkIBelow declName
-    if hasUnit && hasProd then mkBRecOn declName
-    if hasUnit && hasProd then mkBInductionOn declName
 
 private def addDefaults (lctx : LocalContext) (fieldInfos : Array StructFieldInfo) : TermElabM Unit := do
   withLCtx lctx (← getLocalInstances) do
@@ -940,6 +928,8 @@ private def mkInductiveType (view : StructView) (indFVar : Expr) (levelNames : L
   let levelParams := levelNames.map mkLevelParam
   let const := mkConst view.declName levelParams
   let ctorType ← forallBoundedTelescope ctor.type numParams fun params type => do
+    if type.containsFVar indFVar.fvarId! then
+      throwErrorAt view.ref "Recursive structures are not yet supported."
     let type := type.replace fun e =>
       if e == indFVar then
         mkAppN const (params.extract 0 numVars)
@@ -948,23 +938,6 @@ private def mkInductiveType (view : StructView) (indFVar : Expr) (levelNames : L
     instantiateMVars (← mkForallFVars params type)
   return { name := view.declName, type := ← instantiateMVars type, ctors := [{ ctor with type := ← instantiateMVars ctorType }] }
 
-/--
-Precomputes the structure's resolution order.
-Option `structure.strictResolutionOrder` controls whether to create a warning if the C3 algorithm failed.
--/
-private def checkResolutionOrder (structName : Name) : TermElabM Unit := do
-  let resolutionOrderResult ← computeStructureResolutionOrder structName (relaxed := !structure.strictResolutionOrder.get (← getOptions))
-  trace[Elab.structure.resolutionOrder] "computed resolution order: {resolutionOrderResult.resolutionOrder}"
-  unless resolutionOrderResult.conflicts.isEmpty do
-    let mut defects : List MessageData := []
-    for conflict in resolutionOrderResult.conflicts do
-      let parentKind direct := if direct then "parent" else "indirect parent"
-      let conflicts := conflict.conflicts.map fun (isDirect, name) =>
-        m!"{parentKind isDirect} '{MessageData.ofConstName name}'"
-      defects := m!"- {parentKind conflict.isDirectParent} '{MessageData.ofConstName conflict.badParent}' \
-        must come after {MessageData.andList conflicts.toList}" :: defects
-    logWarning m!"failed to compute strict resolution order:\n{MessageData.joinSep defects.reverse "\n"}"
-
 def mkStructureDecl (vars : Array Expr) (view : StructView) : TermElabM Unit := Term.withoutSavingRecAppSyntax do
   let scopeLevelNames ← Term.getLevelNames
   let isUnsafe := view.modifiers.isUnsafe
@@ -1030,8 +1003,6 @@ def mkStructureDecl (vars : Array Expr) (view : StructView) : TermElabM Unit :=
             else
               mkCoercionToCopiedParent levelParams params view parent.structName parent.type
           setStructureParents view.declName parentInfos
-          checkResolutionOrder view.declName
-
           let lctx ← getLCtx
           /- The `lctx` and `defaultAuxDecls` are used to create the auxiliary "default value" declarations
             The parameters `params` for these definitions must be marked as implicit, and all others as explicit. -/
@@ -1069,8 +1040,6 @@ def elabStructure (modifiers : Modifiers) (stx : Syntax) : CommandElabM Unit :=
     pure view
   elabStructureViewPostprocessing view
 
-builtin_initialize
-  registerTraceClass `Elab.structure
-  registerTraceClass `Elab.structure.resolutionOrder
+builtin_initialize registerTraceClass `Elab.structure
 
 end Lean.Elab.Command

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

@@ -35,13 +35,9 @@ Reconstruct bit by bit which value expression must have had which `BitVec` value
 expression - pair values.
 -/
 def reconstructCounterExample (var2Cnf : Std.HashMap BVBit Nat) (assignment : Array (Bool × Nat))
-    (aigSize : Nat) (atomsAssignment : Std.HashMap Nat (Nat × Expr × Bool)) :
+    (aigSize : Nat) (atomsAssignment : Std.HashMap Nat (Nat × Expr)) :
     Array (Expr × BVExpr.PackedBitVec) := Id.run do
   let mut sparseMap : Std.HashMap Nat (RBMap Nat Bool Ord.compare) := {}
-  let filter bvBit _ :=
-    let (_, _, synthetic) := atomsAssignment.get! bvBit.var
-    !synthetic
-  let var2Cnf := var2Cnf.filter filter
   for (bitVar, cnfVar) in var2Cnf.toArray do
     /-
     The setup of the variables in CNF is as follows:
@@ -74,7 +70,7 @@ def reconstructCounterExample (var2Cnf : Std.HashMap BVBit Nat) (assignment : Ar
       if bitValue then
         value := value ||| (1 <<< currentBit)
       currentBit := currentBit + 1
-    let (_, atomExpr, _) := atomsAssignment.get! bitVecVar
+    let atomExpr := atomsAssignment.get! bitVecVar |>.snd
     finalMap := finalMap.push (atomExpr, ⟨BitVec.ofNat currentBit value⟩)
   return finalMap
 
@@ -105,7 +101,7 @@ structure UnsatProver.Result where
   proof : Expr
   lratCert : LratCert
 
-abbrev UnsatProver := MVarId → ReflectionResult → Std.HashMap Nat (Nat × Expr × Bool) →
+abbrev UnsatProver := MVarId → ReflectionResult → Std.HashMap Nat (Nat × Expr) →
     MetaM (Except CounterExample UnsatProver.Result)
 
 /--
@@ -187,7 +183,7 @@ def explainCounterExampleQuality (counterExample : CounterExample) : MetaM Messa
     return err
 
 def lratBitblaster (goal : MVarId) (cfg : TacticContext) (reflectionResult : ReflectionResult)
-    (atomsAssignment : Std.HashMap Nat (Nat × Expr × Bool)) :
+    (atomsAssignment : Std.HashMap Nat (Nat × Expr)) :
     MetaM (Except CounterExample UnsatProver.Result) := do
   let bvExpr := reflectionResult.bvExpr
   let entry ←
@@ -257,8 +253,7 @@ def closeWithBVReflection (g : MVarId) (unsatProver : UnsatProver) :
         reflectBV g
     trace[Meta.Tactic.bv] "Reflected bv logical expression: {reflectionResult.bvExpr}"
 
-    let flipper := (fun (expr, {width, atomNumber, synthetic}) => (atomNumber, (width, expr, synthetic)))
-    let atomsPairs := (← getThe State).atoms.toList.map flipper
+    let atomsPairs := (← getThe State).atoms.toList.map (fun (expr, ⟨width, ident⟩) => (ident, (width, expr)))
     let atomsAssignment := Std.HashMap.ofList atomsPairs
     match ← unsatProver g reflectionResult atomsAssignment with
     | .ok ⟨bvExprUnsat, cert⟩ =>

src/Lean/Elab/Tactic/BVDecide/Frontend/BVDecide/Reflect.lean

@@ -107,25 +107,6 @@ where
 
 open Lean.Meta
 
-/--
-A `BitVec` atom.
--/
-structure Atom where
-  /--
-  The width of the `BitVec` that is being abstracted.
-  -/
-  width : Nat
-  /--
-  A unique numeric identifier for the atom.
-  -/
-  atomNumber : Nat
-  /--
-  Whether the atom is synthetic. The effect of this is that values for this atom are not considered
-  for the counter example deriviation. This is for example useful when we introduce an atom over
-  an expression, together with additional lemmas that fully describe the behavior of the atom.
-  -/
-  synthetic : Bool
-
 /--
 The state of the reflection monad
 -/
@@ -134,7 +115,7 @@ structure State where
   The atoms encountered so far. Saved as a map from `BitVec` expressions to a (width, atomNumber)
   pair.
   -/
-  atoms : Std.HashMap Expr Atom := {}
+  atoms : Std.HashMap Expr (Nat × Nat) := {}
   /--
   A cache for `atomsAssignment`.
   -/
@@ -227,8 +208,8 @@ def run (m : M α) : MetaM α :=
 Retrieve the atoms as pairs of their width and expression.
 -/
 def atoms : M (List (Nat × Expr)) := do
-  let sortedAtoms := (← getThe State).atoms.toArray.qsort (·.2.atomNumber < ·.2.atomNumber)
-  return sortedAtoms.map (fun (expr, {width, ..}) => (width, expr)) |>.toList
+  let sortedAtoms := (← getThe State).atoms.toArray.qsort (·.2.2 < ·.2.2)
+  return sortedAtoms.map (fun (expr, width, _) => (width, expr)) |>.toList
 
 /--
 Retrieve a `BitVec.Assignment` representing the atoms we found so far.
@@ -239,17 +220,16 @@ def atomsAssignment : M Expr := do
 /--
 Look up an expression in the atoms, recording it if it has not previously appeared.
 -/
-def lookup (e : Expr) (width : Nat) (synthetic : Bool) : M Nat := do
+def lookup (e : Expr) (width : Nat) : M Nat := do
   match (← getThe State).atoms[e]? with
-  | some atom =>
-    if width != atom.width then
+  | some (width', ident) =>
+    if width != width' then
       panic! "The same atom occurs with different widths, this is a bug"
-    return atom.atomNumber
+    return ident
   | none =>
-    trace[Meta.Tactic.bv] "New atom of width {width}, synthetic? {synthetic}: {e}"
+    trace[Meta.Tactic.bv] "New atom of width {width}: {e}"
     let ident ← modifyGetThe State fun s =>
-      let newAtom := { width, synthetic, atomNumber := s.atoms.size}
-      (s.atoms.size, { s with atoms := s.atoms.insert e newAtom })
+      (s.atoms.size, { s with atoms := s.atoms.insert e (width, s.atoms.size) })
     updateAtomsAssignment
     return ident
 where

src/Lean/Elab/Tactic/BVDecide/Frontend/BVDecide/ReifiedBVExpr.lean

@@ -32,10 +32,10 @@ def mkBVRefl (w : Nat) (expr : Expr) : Expr :=
    expr
 
 /--
-Register `e` as an atom of `width` that might potentially be `synthetic`.
+Register `e` as an atom of width `width`.
 -/
-def mkAtom (e : Expr) (width : Nat) (synthetic : Bool) : M ReifiedBVExpr := do
-  let ident ← M.lookup e width synthetic
+def mkAtom (e : Expr) (width : Nat) : M ReifiedBVExpr := do
+  let ident ← M.lookup e width
   let expr := mkApp2 (mkConst ``BVExpr.var) (toExpr width) (toExpr ident)
   let proof := do
     let evalExpr ← mkEvalExpr width expr
@@ -55,13 +55,13 @@ def getNatOrBvValue? (ty : Expr) (expr : Expr) : M (Option Nat) := do
   | _ => return none
 
 /--
-Construct an uninterpreted `BitVec` atom from `x`, potentially `synthetic`.
+Construct an uninterpreted `BitVec` atom from `x`.
 -/
-def bitVecAtom (x : Expr) (synthetic : Bool) : M (Option ReifiedBVExpr) := do
+def bitVecAtom (x : Expr) : M (Option ReifiedBVExpr) := do
   let t ← instantiateMVars (← whnfR (← inferType x))
   let_expr BitVec widthExpr := t | return none
   let some width ← getNatValue? widthExpr | return none
-  let atom ← mkAtom x width synthetic
+  let atom ← mkAtom x width
   return some atom
 
 /--

src/Lean/Elab/Tactic/BVDecide/Frontend/BVDecide/ReifiedBVPred.lean

@@ -31,7 +31,7 @@ def boolAtom (t : Expr) : M (Option ReifiedBVPred) := do
   -/
   let ty ← inferType t
   let_expr Bool := ty | return none
-  let atom ← ReifiedBVExpr.mkAtom (mkApp (mkConst ``BitVec.ofBool) t) 1 false
+  let atom ← ReifiedBVExpr.mkAtom (mkApp (mkConst ``BitVec.ofBool) t) 1
   let bvExpr : BVPred := .getLsbD atom.bvExpr 0
   let expr := mkApp3 (mkConst ``BVPred.getLsbD) (toExpr 1) atom.expr (toExpr 0)
   let proof := do

src/Lean/Elab/Tactic/BVDecide/Frontend/BVDecide/Reify.lean

@@ -209,7 +209,7 @@ where
       let_expr Eq α discrExpr val := discrExpr | return none
       let_expr Bool := α | return none
       let_expr Bool.true := val | return none
-      let some atom ← ReifiedBVExpr.bitVecAtom x true | return none
+      let some atom ← ReifiedBVExpr.bitVecAtom x | return none
       let some discr ← ReifiedBVLogical.of discrExpr | return none
       let some lhs ← goOrAtom lhsExpr | return none
       let some rhs ← goOrAtom rhsExpr | return none
@@ -226,7 +226,7 @@ where
     let res ← go x
     match res with
     | some exp => return some exp
-    | none => ReifiedBVExpr.bitVecAtom x false
+    | none => ReifiedBVExpr.bitVecAtom x
 
   shiftConstLikeReflection (distance : Nat) (innerExpr : Expr) (shiftOp : Nat → BVUnOp)
       (shiftOpName : Name) (congrThm : Name) :
@@ -316,7 +316,7 @@ where
     return mkApp4 congrProof (toExpr inner.width) innerExpr innerEval innerProof
 
   goBvLit (x : Expr) : M (Option ReifiedBVExpr) := do
-    let some ⟨_, bvVal⟩ ← getBitVecValue? x | return ← ReifiedBVExpr.bitVecAtom x false
+    let some ⟨_, bvVal⟩ ← getBitVecValue? x | return ← ReifiedBVExpr.bitVecAtom x
     ReifiedBVExpr.mkBVConst bvVal
 
 /--

src/Lean/Elab/Tactic/BVDecide/Frontend/Normalize.lean

@@ -112,6 +112,7 @@ builtin_simproc [bv_normalize] bv_add_const' (((_ : BitVec _) + (_ : BitVec _))
     | some ⟨w', exp1Val⟩ =>
       if h : w = w' then
         let newLhs := exp3Val + h ▸ exp1Val
+        -- TODO
         let expr ← mkAppM ``HAdd.hAdd #[toExpr newLhs, exp2]
         let proof := proofBuilder ``Std.Tactic.BVDecide.Normalize.BitVec.add_const_left'
         return .visit { expr := expr, proof? := some proof }
@@ -177,33 +178,6 @@ def rewriteRulesPass : Pass := fun goal => do
   let some (_, newGoal) := result? | return none
   return newGoal
 
-/--
-Substitute embedded constraints. That is look for hypotheses of the form `h : x = true` and use
-them to substitute occurences of `x` within other hypotheses
--/
-def embeddedConstraintPass : Pass := fun goal =>
-  goal.withContext do
-    let hyps ← goal.getNondepPropHyps
-    let relevanceFilter acc hyp := do
-      let typ ← hyp.getType
-      let_expr Eq α _ rhs := typ | return acc
-      let_expr Bool := α | return acc
-      let_expr Bool.true := rhs | return acc
-      let localDecl ← hyp.getDecl
-      let proof  := localDecl.toExpr
-      acc.addTheorem (.fvar hyp) proof
-    let relevantHyps : SimpTheoremsArray ← hyps.foldlM (init := #[]) relevanceFilter
-
-    let simpCtx : Simp.Context := {
-      config := { failIfUnchanged := false }
-      simpTheorems := relevantHyps
-      congrTheorems := (← getSimpCongrTheorems)
-    }
-
-    let ⟨result?, _⟩ ← simpGoal goal (ctx := simpCtx) (fvarIdsToSimp := hyps)
-    let some (_, newGoal) := result? | return none
-    return newGoal
-
 /--
 Normalize with respect to Associativity and Commutativity.
 -/
@@ -222,7 +196,7 @@ def acNormalizePass : Pass := fun goal => do
 /--
 The normalization passes used by `bv_normalize` and thus `bv_decide`.
 -/
-def defaultPipeline : List Pass := [rewriteRulesPass, embeddedConstraintPass]
+def defaultPipeline : List Pass := [rewriteRulesPass]
 
 def passPipeline : MetaM (List Pass) := do
   let opts ← getOptions
@@ -248,8 +222,8 @@ def evalBVNormalize : Tactic := fun
   | `(tactic| bv_normalize) => do
     let g ← getMainGoal
     match ← bvNormalize g with
-    | some newGoal => replaceMainGoal [newGoal]
-    | none => replaceMainGoal []
+    | some newGoal => setGoals [newGoal]
+    | none => setGoals []
   | _ => throwUnsupportedSyntax
 
 end Frontend.Normalize

src/Lean/Elab/Tactic/BuiltinTactic.lean

@@ -263,26 +263,19 @@ private def getOptRotation (stx : Syntax) : Nat :=
 @[builtin_tactic Parser.Tactic.allGoals] def evalAllGoals : Tactic := fun stx => do
   let mvarIds ← getGoals
   let mut mvarIdsNew := #[]
-  let mut abort := false
-  let mut mctxSaved ← getMCtx
   for mvarId in mvarIds do
     unless (← mvarId.isAssigned) do
       setGoals [mvarId]
-      abort ← Tactic.tryCatch
+      mvarIdsNew ← Tactic.tryCatch
         (do
           evalTactic stx[1]
-          pure abort)
+          return mvarIdsNew ++ (← getUnsolvedGoals))
         (fun ex => do
           if (← read).recover then
             logException ex
-            pure true
+            return mvarIdsNew.push mvarId
           else
             throw ex)
-      mvarIdsNew := mvarIdsNew ++ (← getUnsolvedGoals)
-  if abort then
-    setMCtx mctxSaved
-    mvarIds.forM fun mvarId => unless (← mvarId.isAssigned) do admitGoal mvarId
-    throwAbortTactic
   setGoals mvarIdsNew.toList
 
 @[builtin_tactic Parser.Tactic.anyGoals] def evalAnyGoals : Tactic := fun stx => do
@@ -472,7 +465,7 @@ def renameInaccessibles (mvarId : MVarId) (hs : TSyntaxArray ``binderIdent) : Ta
         let inaccessible := !(extractMacroScopes localDecl.userName |>.equalScope callerScopes)
         let shadowed := found.contains localDecl.userName
         if inaccessible || shadowed then
-          if let `(binderIdent| $h:ident) := hs.back! then
+          if let `(binderIdent| $h:ident) := hs.back then
             let newName := h.getId
             lctx := lctx.setUserName localDecl.fvarId newName
             info := info.push (localDecl.fvarId, h)

src/Lean/Elab/Tactic/Config.lean

@@ -1,7 +1,7 @@
 /-
 Copyright (c) 2021 Microsoft Corporation. All rights reserved.
 Released under Apache 2.0 license as described in the file LICENSE.
-Authors: Leonardo de Moura, Kyle Miller
+Authors: Leonardo de Moura
 -/
 prelude
 import Lean.Meta.Eval
@@ -10,174 +10,25 @@ import Lean.Elab.SyntheticMVars
 import Lean.Linter.MissingDocs
 
 namespace Lean.Elab.Tactic
-open Meta Parser.Tactic Command
-
-private structure ConfigItemView where
-  ref : Syntax
-  option : Ident
-  value : Term
-  /-- Whether this was using `+`/`-`, to be able to give a better error message on type mismatch. -/
-  (bool : Bool := false)
-
-/-- Interprets the `config` as an array of option/value pairs. -/
-private def mkConfigItemViews (c : TSyntaxArray ``configItem) : Array ConfigItemView :=
-  c.map fun item =>
-    match item with
-    | `(configItem| ($option:ident := $value)) => { ref := item, option, value }
-    | `(configItem| +$option) => { ref := item, option, bool := true, value := mkCIdentFrom item ``true }
-    | `(configItem| -$option) => { ref := item, option, bool := true, value := mkCIdentFrom item ``false }
-    | `(config| (config%$tk := $value)) => { ref := item, option := mkCIdentFrom tk `config, value := value }
-    | _ => { ref := item, option := ⟨Syntax.missing⟩, value := ⟨Syntax.missing⟩ }
-
-/--
-Expands a field access into full field access like `toB.toA.x`.
-Returns that and the last projection function for `x` itself.
--/
-private def expandFieldName (structName : Name) (fieldName : Name) : MetaM (Name × Name) := do
-  let env ← getEnv
-  unless isStructure env structName do throwError "'{.ofConstName structName}' is not a structure"
-  let some baseStructName := findField? env structName fieldName
-    | throwError "structure '{.ofConstName structName}' does not have a field named '{fieldName}'"
-  let some path := getPathToBaseStructure? env baseStructName structName
-    | throwError "(internal error) failed to access field '{fieldName}' in parent structure"
-  let field := path.foldl (init := .anonymous) (fun acc s => Name.appendCore acc <| Name.mkSimple s.getString!) ++ fieldName
-  let fieldInfo := (getFieldInfo? env baseStructName fieldName).get!
-  return (field, fieldInfo.projFn)
-
-
-/--
-Given a hierarchical name `field`, returns the fully resolved field access, the base struct name, and the last projection function.
--/
-private partial def expandField (structName : Name) (field : Name) : MetaM (Name × Name) := do
-  match field with
-  | .num .. | .anonymous => throwError m!"invalid configuration field"
-  | .str .anonymous fieldName => expandFieldName structName (Name.mkSimple fieldName)
-  | .str field' fieldName =>
-    let (field', projFn) ← expandField structName field'
-    let notStructure {α} : MetaM α := throwError "field '{field'}' of structure '{.ofConstName structName}' is not a structure"
-    let .const structName' _ := (← getConstInfo projFn).type.getForallBody | notStructure
-    unless isStructure (← getEnv) structName' do notStructure
-    let (field'', projFn) ← expandFieldName structName' (Name.mkSimple fieldName)
-    return (field' ++ field'', projFn)
-
-/-- Elaborates a tactic configuration. -/
-private def elabConfig (recover : Bool) (structName : Name) (items : Array ConfigItemView) : TermElabM Expr :=
-  withoutModifyingStateWithInfoAndMessages <| withLCtx {} {} <| withSaveInfoContext do
-    let mkStructInst (source? : Option Term) (fields : TSyntaxArray ``Parser.Term.structInstField) : TermElabM Term :=
-      match source? with
-      | some source => `({$source with $fields* : $(mkCIdent structName)})
-      | none        => `({$fields* : $(mkCIdent structName)})
-    let mut source? : Option Term := none
-    let mut seenFields : NameSet := {}
-    let mut fields : TSyntaxArray ``Parser.Term.structInstField := #[]
-    for item in items do
-      try
-        let option := item.option.getId.eraseMacroScopes
-        if option == `config then
-          unless fields.isEmpty do
-            -- Flush fields. Even though these values will not be used, we still want to elaborate them.
-            source? ← mkStructInst source? fields
-            seenFields := {}
-            fields := #[]
-          let valSrc ← withRef item.value `(($item.value : $(mkCIdent structName)))
-          if let some source := source? then
-            source? ← withRef item.value `({$valSrc, $source with : $(mkCIdent structName)})
-          else
-            source? := valSrc
-        else
-          addCompletionInfo <| CompletionInfo.fieldId item.option option {} structName
-          let (path, projFn) ← withRef item.option <| expandField structName option
-          if item.bool then
-            -- Verify that the type is `Bool`
-            unless (← getConstInfo projFn).type.bindingBody! == .const ``Bool [] do
-              throwErrorAt item.ref m!"option is not boolean-valued, so '({option} := ...)' syntax must be used"
-          let value ←
-            match item.value with
-            | `(by $seq:tacticSeq) =>
-              -- Special case: `(opt := by tacs)` uses the `tacs` syntax itself
-              withRef item.value <| `(Unhygienic.run `(tacticSeq| $seq))
-            | value => pure value
-          if seenFields.contains path then
-            -- Flush fields. There is a duplicate, but we still want to elaborate both.
-            source? ← mkStructInst source? fields
-            seenFields := {}
-            fields := #[]
-          fields := fields.push <| ← `(Parser.Term.structInstField|
-            $(mkCIdentFrom item.option path (canonical := true)):ident := $value)
-          seenFields := seenFields.insert path
-      catch ex =>
-        if recover then
-          logException ex
-        else
-          throw ex
-    let stx : Term ← mkStructInst source? fields
-    let e ← Term.withSynthesize <| Term.elabTermEnsuringType stx (mkConst structName)
-    instantiateMVars e
-
-private def mkConfigElaborator
-    (doc? : Option (TSyntax ``Parser.Command.docComment)) (elabName type monadName : Ident)
-    (adapt recover : Term) : MacroM (TSyntax `command) := do
-  let empty ← withRef type `({ : $type})
-  `(unsafe def evalUnsafe (e : Expr) : TermElabM $type :=
-      Meta.evalExpr' (safety := .unsafe) $type ``$type e
-    @[implemented_by evalUnsafe] opaque eval (e : Expr) : TermElabM $type
-    $[$doc?:docComment]?
-    def $elabName (optConfig : Syntax) : $monadName $type := $adapt do
-      let recover := $recover
-      let go : TermElabM $type := withRef optConfig do
-        let items := mkConfigItemViews (getConfigItems optConfig)
-        if items.isEmpty then
-          return $empty
-        unless (← getEnv).contains ``$type do
-          throwError m!"error evaluating configuration, environment does not yet contain type {``$type}"
-        let c ← elabConfig recover ``$type items
-        if c.hasSyntheticSorry then
-          -- An error is already logged, return the default.
-          return $empty
-        if c.hasSorry then
-          throwError m!"configuration contains 'sorry'"
-        try
-          let res ← eval c
-          return res
-        catch ex =>
-          let msg := m!"error evaluating configuration\n{indentD c}\n\nException: {ex.toMessageData}"
-          if false then
-            logError msg
-            return $empty
-          else
-            throwError msg
-      go)
-
-/-!
-`declare_config_elab elabName TypeName` declares a function `elabName : Syntax → TacticM TypeName`
-that elaborates a tactic configuration.
-The tactic configuration can be from `Lean.Parser.Tactic.optConfig` or `Lean.Parser.Tactic.config`,
-and these can also be wrapped in null nodes (for example, from `(config)?`).
-
-The elaborator responds to the current recovery state.
-
-For defining elaborators for commands, use `declare_command_config_elab`.
--/
-macro (name := configElab) doc?:(docComment)? "declare_config_elab" elabName:ident type:ident : command => do
-  mkConfigElaborator doc? elabName type (mkCIdent ``TacticM) (mkCIdent ``id) (← `((← read).recover))
+open Meta
+macro (name := configElab) doc?:(docComment)? "declare_config_elab" elabName:ident type:ident : command =>
+ `(unsafe def evalUnsafe (e : Expr) : TermElabM $type :=
+    Meta.evalExpr' (safety := .unsafe) $type ``$type e
+   @[implemented_by evalUnsafe] opaque eval (e : Expr) : TermElabM $type
+   $[$doc?:docComment]?
+   def $elabName (optConfig : Syntax) : TermElabM $type := do
+     if optConfig.isNone then
+       return { : $type }
+     else
+       let c ← withoutModifyingStateWithInfoAndMessages <| withLCtx {} {} <| withSaveInfoContext <| Term.withSynthesize do
+         let c ← Term.elabTermEnsuringType optConfig[0][3] (Lean.mkConst ``$type)
+         Term.synthesizeSyntheticMVarsNoPostponing
+         instantiateMVars c
+       eval c
+  )
 
 open Linter.MissingDocs in
 @[builtin_missing_docs_handler Elab.Tactic.configElab]
 def checkConfigElab : SimpleHandler := mkSimpleHandler "config elab"
 
-/-!
-`declare_command_config_elab elabName TypeName` declares a function `elabName : Syntax → CommandElabM TypeName`
-that elaborates a command configuration.
-The configuration can be from `Lean.Parser.Tactic.optConfig` or `Lean.Parser.Tactic.config`,
-and these can also be wrapped in null nodes (for example, from `(config)?`).
-
-The elaborator has error recovery enabled.
--/
-macro (name := commandConfigElab) doc?:(docComment)? "declare_command_config_elab" elabName:ident type:ident : command => do
-  mkConfigElaborator doc? elabName type (mkCIdent ``CommandElabM) (mkCIdent ``liftTermElabM) (mkCIdent ``true)
-
-open Linter.MissingDocs in
-@[builtin_missing_docs_handler Elab.Tactic.commandConfigElab]
-def checkCommandConfigElab : SimpleHandler := mkSimpleHandler "config elab"
-
 end Lean.Elab.Tactic

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

@@ -11,8 +11,6 @@ import Lean.Elab.Tactic.Conv.Basic
 namespace Lean.Elab.Tactic.Conv
 open Meta
 
-@[builtin_tactic Lean.Parser.Tactic.Conv.skip] def evalSkip : Tactic := fun _ => pure ()
-
 private def congrImplies (mvarId : MVarId) : MetaM (List MVarId) := do
   let [mvarId₁, mvarId₂, _, _] ← mvarId.apply (← mkConstWithFreshMVarLevels ``implies_congr) | throwError "'apply implies_congr' unexpected result"
   let mvarId₁ ← markAsConvGoal mvarId₁
@@ -74,14 +72,6 @@ private partial def mkCongrThm (origTag : Name) (f : Expr) (args : Array Expr) (
     mvarIdsNewInsts := mvarIdsNewInsts ++ mvarIdsNewInsts'
   return (proof, mvarIdsNew, mvarIdsNewInsts)
 
-private def resolveRhs (tacticName : String) (rhs rhs' : Expr) : MetaM Unit := do
-  unless (← isDefEqGuarded rhs rhs') do
-    throwError "invalid '{tacticName}' conv tactic, failed to resolve{indentExpr rhs}\n=?={indentExpr rhs'}"
-
-private def resolveRhsFromProof (tacticName : String) (rhs proof : Expr) : MetaM Unit := do
-  let some (_, _, rhs') := (← whnf (← inferType proof)).eq? | throwError "'{tacticName}' conv tactic failed, equality expected"
-  resolveRhs tacticName rhs rhs'
-
 def congr (mvarId : MVarId) (addImplicitArgs := false) (nameSubgoals := true) :
     MetaM (List (Option MVarId)) := mvarId.withContext do
   let origTag ← mvarId.getTag
@@ -92,7 +82,9 @@ def congr (mvarId : MVarId) (addImplicitArgs := false) (nameSubgoals := true) :
   else if lhs.isApp then
     let (proof, mvarIdsNew, mvarIdsNewInsts) ←
       mkCongrThm origTag lhs.getAppFn lhs.getAppArgs addImplicitArgs nameSubgoals
-    resolveRhsFromProof "congr" rhs proof
+    let some (_, _, rhs') := (← whnf (← inferType proof)).eq? | throwError "'congr' conv tactic failed, equality expected"
+    unless (← isDefEqGuarded rhs rhs') do
+      throwError "invalid 'congr' conv tactic, failed to resolve{indentExpr rhs}\n=?={indentExpr rhs'}"
     mvarId.assign proof
     return mvarIdsNew.toList ++ mvarIdsNewInsts.toList
   else
@@ -101,7 +93,42 @@ def congr (mvarId : MVarId) (addImplicitArgs := false) (nameSubgoals := true) :
 @[builtin_tactic Lean.Parser.Tactic.Conv.congr] def evalCongr : Tactic := fun _ => do
   replaceMainGoal <| List.filterMap id (← congr (← getMainGoal))
 
-/-- Implementation of `arg 0`. -/
+-- mvarIds is the list of goals produced by congr. We only want to change the one at position `i`
+-- so this closes all other equality goals with `rfl.`. There are non-equality goals produced
+-- by `congr` (e.g. dependent instances), these are kept as goals.
+private def selectIdx (tacticName : String) (mvarIds : List (Option MVarId)) (i : Int) :
+  TacticM Unit := do
+  if i >= 0 then
+    let i := i.toNat
+    if h : i < mvarIds.length then
+      let mut otherGoals := #[]
+      for mvarId? in mvarIds, j in [:mvarIds.length] do
+        match mvarId? with
+        | none => pure ()
+        | some mvarId =>
+          if i != j then
+            if (← mvarId.getType').isEq then
+              mvarId.refl
+            else
+              -- If its not an equality, it's likely a class constraint, to be left open
+              otherGoals := otherGoals.push mvarId
+      match mvarIds[i] with
+      | none => throwError "cannot select argument"
+      | some mvarId => replaceMainGoal (mvarId :: otherGoals.toList)
+      return ()
+  throwError "invalid '{tacticName}' conv tactic, application has only {mvarIds.length} (nondependent) argument(s)"
+
+@[builtin_tactic Lean.Parser.Tactic.Conv.skip] def evalSkip : Tactic := fun _ => pure ()
+
+@[builtin_tactic Lean.Parser.Tactic.Conv.lhs] def evalLhs : Tactic := fun _ => do
+  let mvarIds ← congr (← getMainGoal) (nameSubgoals := false)
+  selectIdx "lhs" mvarIds ((mvarIds.length : Int) - 2)
+
+@[builtin_tactic Lean.Parser.Tactic.Conv.rhs] def evalRhs : Tactic := fun _ => do
+  let mvarIds ← congr (← getMainGoal) (nameSubgoals := false)
+  selectIdx "rhs" mvarIds ((mvarIds.length : Int) - 1)
+
+/-- Implementation of `arg 0` -/
 def congrFunN (mvarId : MVarId) : MetaM MVarId := mvarId.withContext do
   let (lhs, rhs) ← getLhsRhsCore mvarId
   let lhs := (← instantiateMVars lhs).cleanupAnnotations
@@ -109,137 +136,24 @@ def congrFunN (mvarId : MVarId) : MetaM MVarId := mvarId.withContext do
     throwError "invalid 'arg 0' conv tactic, application expected{indentExpr lhs}"
   lhs.withApp fun f xs => do
     let (g, mvarNew) ← mkConvGoalFor f
-    mvarId.assign (← xs.foldlM (init := mvarNew) Meta.mkCongrFun)
-    resolveRhs "arg 0" rhs (mkAppN g xs)
+    mvarId.assign (← xs.foldlM (fun mvar a => Meta.mkCongrFun mvar a) mvarNew)
+    let rhs' := mkAppN g xs
+    unless ← isDefEqGuarded rhs rhs' do
+      throwError "invalid 'arg 0' conv tactic, failed to resolve{indentExpr rhs}\n=?={indentExpr rhs'}"
     return mvarNew.mvarId!
 
-private partial def mkCongrArgZeroThm (tacticName : String) (origTag : Name) (f : Expr) (args : Array Expr) :
-    MetaM (Expr × MVarId × Array MVarId) := do
-  let funInfo ← getFunInfoNArgs f args.size
-  let some congrThm ← mkCongrSimpCore? f funInfo (← getCongrSimpKindsForArgZero funInfo) (subsingletonInstImplicitRhs := false)
-    | throwError "'{tacticName}' conv tactic failed to create congruence theorem"
-  unless congrThm.argKinds[0]! matches .eq do
-    throwError "'{tacticName}' conv tactic failed, cannot select argument"
-  let mut eNew := f
-  let mut proof := congrThm.proof
-  let mut mvarIdNew? := none
-  let mut mvarIdsNewInsts := #[]
-  for h : i in [:congrThm.argKinds.size] do
-    let arg := args[i]!
-    let argInfo := funInfo.paramInfo[i]!
-    match congrThm.argKinds[i] with
-    | .fixed | .cast =>
-      eNew := mkApp eNew arg
-      proof := mkApp proof arg
-    | .eq =>
-      let (rhs, mvarNew) ← mkConvGoalFor arg origTag
-      eNew := mkApp eNew rhs
-      proof := mkApp3 proof arg rhs mvarNew
-      if mvarIdNew?.isSome then throwError "'{tacticName}' conv tactic failed, cannot select argument"
-      mvarIdNew? := some mvarNew.mvarId!
-    | .subsingletonInst =>
-      proof := mkApp proof arg
-      let rhs ← mkFreshExprMVar (← whnf (← inferType proof)).bindingDomain!
-      eNew := mkApp eNew rhs
-      proof := mkApp proof rhs
-      mvarIdsNewInsts := mvarIdsNewInsts.push rhs.mvarId!
-    | .heq | .fixedNoParam => unreachable!
-  let proof' ← args[congrThm.argKinds.size:].foldlM (init := proof) mkCongrFun
-  return (proof', mvarIdNew?.get!, mvarIdsNewInsts)
-
-/--
-Implements `arg` for foralls. If `domain` is true, accesses the domain, otherwise accesses the codomain.
--/
-def congrArgForall (tacticName : String) (domain : Bool) (mvarId : MVarId) (lhs rhs : Expr) : MetaM (List MVarId) := do
-  let .forallE n t b bi := lhs | unreachable!
-  if domain then
-    if !b.hasLooseBVars then
-      let (t', g) ← mkConvGoalFor t (← mvarId.getTag)
-      mvarId.assign <| ← mkAppM ``implies_congr #[g, ← mkEqRefl b]
-      resolveRhs tacticName rhs (.forallE n t' b bi)
-      return [g.mvarId!]
-    else if ← isProp b <&&> isProp lhs then
-      let (_rhs, g) ← mkConvGoalFor t (← mvarId.getTag)
-      let proof ← mkAppM ``forall_prop_congr_dom #[g, .lam n t b .default]
-      resolveRhsFromProof tacticName rhs proof
-      mvarId.assign proof
-      return [g.mvarId!]
-    else
-      throwError m!"'{tacticName}' conv tactic failed, cannot select domain"
-  else
-    withLocalDeclD (← mkFreshUserName n) t fun arg => do
-      let u ← getLevel t
-      let q := b.instantiate1 arg
-      let (q', g) ← mkConvGoalFor q (← mvarId.getTag)
-      let v ← getLevel q
-      let proof := mkAppN (.const ``pi_congr [u, v])
-        #[t, .lam n t b .default, ← mkLambdaFVars #[arg] q', ← mkLambdaFVars #[arg] g]
-      resolveRhsFromProof tacticName rhs proof
-      mvarId.assign proof
-      return [g.mvarId!]
-
-/-- Implementation of `arg i`. -/
-def congrArgN (tacticName : String) (mvarId : MVarId) (i : Int) (explicit : Bool) : MetaM (List MVarId) := mvarId.withContext do
-  let (lhs, rhs) ← getLhsRhsCore mvarId
-  let lhs := (← instantiateMVars lhs).cleanupAnnotations
-  if lhs.isForall then
-    if i < -2 || i == 0 || i > 2 then throwError "invalid '{tacticName}' conv tactic, index is out of bounds for pi type"
-    let domain := i == 1 || i == -2
-    return ← congrArgForall tacticName domain mvarId lhs rhs
-  else if lhs.isApp then
-    lhs.withApp fun f xs => do
-      let (f, xs) ← applyArgs f xs i
-      let (proof, mvarIdNew, mvarIdsNewInsts) ← mkCongrArgZeroThm tacticName (← mvarId.getTag) f xs
-      resolveRhsFromProof tacticName rhs proof
-      mvarId.assign proof
-      return mvarIdNew :: mvarIdsNewInsts.toList
-  else
-    throwError "invalid '{tacticName}' conv tactic, application or implication expected{indentExpr lhs}"
-where
-  applyArgs (f : Expr) (xs : Array Expr) (i : Int) : MetaM (Expr × Array Expr) := do
-    if explicit then
-      let i := if i > 0 then i - 1 else i + xs.size
-      if i < 0 || i ≥ xs.size then
-        throwError "invalid '{tacticName}' tactic, application has {xs.size} arguments but the index is out of bounds"
-      let idx := i.natAbs
-      return (mkAppN f xs[0:idx], xs[idx:])
-    else
-      let mut fType ← inferType f
-      let mut j := 0
-      let mut explicitIdxs := #[]
-      for k in [0:xs.size] do
-        unless fType.isForall do
-          fType ← withTransparency .all <| whnf (fType.instantiateRevRange j k xs)
-          j := k
-        let .forallE _ _ b bi := fType | failure
-        fType := b
-        if bi.isExplicit then
-          explicitIdxs := explicitIdxs.push k
-      let i := if i > 0 then i - 1 else i + explicitIdxs.size
-      if i < 0 || i ≥ explicitIdxs.size then
-        throwError "invalid '{tacticName}' tactic, application has {xs.size} explicit argument(s) but the index is out of bounds"
-      let idx := explicitIdxs[i.natAbs]!
-      return (mkAppN f xs[0:idx], xs[idx:])
-
-def evalArg (tacticName : String) (i : Int) (explicit : Bool) : TacticM Unit := do
-  if i == 0 then
-    replaceMainGoal [← congrFunN (← getMainGoal)]
-  else
-    replaceMainGoal (← congrArgN tacticName (← getMainGoal) i explicit)
-
-@[builtin_tactic Lean.Parser.Tactic.Conv.arg] def elabArg : Tactic := fun stx => do
+@[builtin_tactic Lean.Parser.Tactic.Conv.arg] def evalArg : Tactic := fun stx => do
   match stx with
-  | `(conv| arg $[@%$tk?]? $[-%$neg?]? $i:num) =>
-    let i : Int := if neg?.isSome then -i.getNat else i.getNat
-    evalArg "arg" i (explicit := tk?.isSome)
+  | `(conv| arg $[@%$tk?]? $i:num) =>
+    let i := i.getNat
+    if i == 0 then
+      replaceMainGoal [← congrFunN (← getMainGoal)]
+    else
+      let i := i - 1
+      let mvarIds ← congr (← getMainGoal) (addImplicitArgs := tk?.isSome) (nameSubgoals := false)
+      selectIdx "arg" mvarIds i
   | _ => throwUnsupportedSyntax
 
-@[builtin_tactic Lean.Parser.Tactic.Conv.lhs] def evalLhs : Tactic := fun _ => do
-  evalArg "lhs" (-2) false
-
-@[builtin_tactic Lean.Parser.Tactic.Conv.rhs] def evalRhs : Tactic := fun _ => do
-  evalArg "rhs" (-1) false
-
 @[builtin_tactic Lean.Parser.Tactic.Conv.«fun»] def evalFun : Tactic := fun _ => do
   let mvarId ← getMainGoal
   mvarId.withContext do
@@ -249,7 +163,9 @@ def evalArg (tacticName : String) (i : Int) (explicit : Bool) : TacticM Unit :=
       | throwError "invalid 'fun' conv tactic, application expected{indentExpr lhs}"
     let (g, mvarNew) ← mkConvGoalFor f
     mvarId.assign (← Meta.mkCongrFun mvarNew a)
-    resolveRhs "fun" rhs (.app g a)
+    let rhs' := .app g a
+    unless ← isDefEqGuarded rhs rhs' do
+      throwError "invalid 'fun' conv tactic, failed to resolve{indentExpr rhs}\n=?={indentExpr rhs'}"
     replaceMainGoal [mvarNew.mvarId!]
 
 def extLetBodyCongr? (mvarId : MVarId) (lhs rhs : Expr) : MetaM (Option MVarId) := do
@@ -293,7 +209,9 @@ private def extCore (mvarId : MVarId) (userName? : Option Name) : MetaM MVarId :
         let (qa, mvarNew) ← mkConvGoalFor pa
         let q ← mkLambdaFVars #[a] qa
         let h ← mkLambdaFVars #[a] mvarNew
-        resolveRhs "ext" rhs (← mkForallFVars #[a] qa)
+        let rhs' ← mkForallFVars #[a] qa
+        unless (← isDefEqGuarded rhs rhs') do
+          throwError "invalid 'ext' conv tactic, failed to resolve{indentExpr rhs}\n=?={indentExpr rhs'}"
         return (q, h, mvarNew)
       let proof := mkApp4 (mkConst ``forall_congr [u]) d p q h
       mvarId.assign proof
@@ -320,22 +238,4 @@ private def ext (userName? : Option Name) : TacticM Unit := do
     for id in ids do
       withRef id <| ext id.getId
 
--- syntax (name := enter) "enter" " [" enterArg,+ "]" : conv
-@[builtin_tactic Lean.Parser.Tactic.Conv.enter] def evalEnter : Tactic := fun stx => do
-  let token := stx[0]
-  let lbrak := stx[1]
-  let enterArgsAndSeps := stx[2].getArgs
-  -- show initial state up to (incl.) `[`
-  withTacticInfoContext (mkNullNode #[token, lbrak]) (pure ())
-  let numEnterArgs := (enterArgsAndSeps.size + 1) / 2
-  for i in [:numEnterArgs] do
-    let enterArg := enterArgsAndSeps[2 * i]!
-    let sep := enterArgsAndSeps.getD (2 * i + 1) .missing
-    -- show state up to (incl.) next `,` and show errors on `enterArg`
-    withTacticInfoContext (mkNullNode #[enterArg, sep]) <| withRef enterArg do
-      match enterArg with
-      | `(Parser.Tactic.Conv.enterArg| $arg:argArg) => evalTactic (← `(conv| arg $arg))
-      | `(Parser.Tactic.Conv.enterArg| $id:ident)   => evalTactic (← `(conv| ext $id))
-      | _ => pure ()
-
 end Lean.Elab.Tactic.Conv

src/Lean/Elab/Tactic/Induction.lean

@@ -208,28 +208,15 @@ private def getAltNumFields (elimInfo : ElimInfo) (altName : Name) : TermElabM N
 private def isWildcard (altStx : Syntax) : Bool :=
   getAltName altStx == `_
 
-private def checkAltNames (alts : Array Alt) (altsSyntax : Array Syntax) : TacticM Unit := do
-  let mut seenNames : Array Name := #[]
+private def checkAltNames (alts : Array Alt) (altsSyntax : Array Syntax) : TacticM Unit :=
   for h : i in [:altsSyntax.size] do
     let altStx := altsSyntax[i]
     if getAltName altStx == `_ && i != altsSyntax.size - 1 then
       withRef altStx <| throwError "invalid occurrence of wildcard alternative, it must be the last alternative"
     let altName := getAltName altStx
     if altName != `_ then
-      if seenNames.contains altName then
-        throwErrorAt altStx s!"duplicate alternative name '{altName}'"
-      seenNames := seenNames.push altName
       unless alts.any (·.name == altName) do
-        let unhandledAlts := alts.filter fun alt => !seenNames.contains alt.name
-        let msg :=
-          if unhandledAlts.isEmpty then
-            m!"invalid alternative name '{altName}', no unhandled alternatives"
-          else
-            let unhandledAltsMessages := unhandledAlts.map (m!"{·.name}")
-            let unhandledAlts := MessageData.orList unhandledAltsMessages.toList
-            m!"invalid alternative name '{altName}', expected {unhandledAlts}"
-        throwErrorAt altStx msg
-
+        throwErrorAt altStx "invalid alternative name '{altName}'"
 
 /-- Given the goal `altMVarId` for a given alternative that introduces `numFields` new variables,
     return the number of explicit variables. Recall that when the `@` is not used, only the explicit variables can

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

@@ -696,9 +696,9 @@ the tactic call `aesop (add 50% tactic Lean.Omega.omegaDefault)`. -/
 def omegaDefault : TacticM Unit := omegaTactic {}
 
 @[builtin_tactic Lean.Parser.Tactic.omega]
-def evalOmega : Tactic
-  | `(tactic| omega $cfg:optConfig) => do
-    let cfg ← elabOmegaConfig cfg
+def evalOmega : Tactic := fun
+  | `(tactic| omega $[$cfg]?) => do
+    let cfg ← elabOmegaConfig (mkOptionalNode cfg)
     omegaTactic cfg
   | _ => throwUnsupportedSyntax
 

src/Lean/Elab/Tactic/Simp.lean

@@ -85,7 +85,7 @@ private def mkDischargeWrapper (optDischargeSyntax : Syntax) : TacticM Simp.Disc
 /-
   `optConfig` is of the form `("(" "config" ":=" term ")")?`
 -/
-def elabSimpConfig (optConfig : Syntax) (kind : SimpKind) : TacticM Meta.Simp.Config := do
+def elabSimpConfig (optConfig : Syntax) (kind : SimpKind) : TermElabM Meta.Simp.Config := do
   match kind with
   | .simp    => elabSimpConfigCore optConfig
   | .simpAll => return (← elabSimpConfigCtxCore optConfig).toConfig
@@ -437,7 +437,7 @@ def withSimpDiagnostics (x : TacticM Simp.Diagnostics) : TacticM Unit := do
   Simp.reportDiag stats
 
 /-
-  "simp" optConfig (discharger)? (" only")? (" [" ((simpStar <|> simpErase <|> simpLemma),*,?) "]")?
+  "simp" (config)? (discharger)? (" only")? (" [" ((simpStar <|> simpErase <|> simpLemma),*,?) "]")?
   (location)?
 -/
 @[builtin_tactic Lean.Parser.Tactic.simp] def evalSimp : Tactic := fun stx => withMainContext do withSimpDiagnostics do

src/Lean/Elab/Tactic/SimpTrace.lean

@@ -25,11 +25,11 @@ def mkSimpCallStx (stx : Syntax) (usedSimps : UsedSimps) : MetaM (TSyntax `tacti
 @[builtin_tactic simpTrace] def evalSimpTrace : Tactic := fun stx =>
   match stx with
   | `(tactic|
-      simp?%$tk $[!%$bang]? $cfg:optConfig $(discharger)? $[only%$o]? $[[$args,*]]? $(loc)?) => withMainContext do withSimpDiagnostics do
+      simp?%$tk $[!%$bang]? $(config)? $(discharger)? $[only%$o]? $[[$args,*]]? $(loc)?) => withMainContext do withSimpDiagnostics do
     let stx ← if bang.isSome then
-      `(tactic| simp!%$tk $cfg:optConfig $(discharger)? $[only%$o]? $[[$args,*]]? $(loc)?)
+      `(tactic| simp!%$tk $(config)? $(discharger)? $[only%$o]? $[[$args,*]]? $(loc)?)
     else
-      `(tactic| simp%$tk $cfg:optConfig $[$discharger]? $[only%$o]? $[[$args,*]]? $(loc)?)
+      `(tactic| simp%$tk $(config)? $(discharger)? $[only%$o]? $[[$args,*]]? $(loc)?)
     let { ctx, simprocs, dischargeWrapper } ← mkSimpContext stx (eraseLocal := false)
     let stats ← dischargeWrapper.with fun discharge? =>
       simpLocation ctx (simprocs := simprocs) discharge? <|
@@ -41,11 +41,11 @@ def mkSimpCallStx (stx : Syntax) (usedSimps : UsedSimps) : MetaM (TSyntax `tacti
 
 @[builtin_tactic simpAllTrace] def evalSimpAllTrace : Tactic := fun stx =>
   match stx with
-  | `(tactic| simp_all?%$tk $[!%$bang]? $cfg:optConfig $(discharger)? $[only%$o]? $[[$args,*]]?) => withSimpDiagnostics do
+  | `(tactic| simp_all?%$tk $[!%$bang]? $(config)? $(discharger)? $[only%$o]? $[[$args,*]]?) => withSimpDiagnostics do
     let stx ← if bang.isSome then
-      `(tactic| simp_all!%$tk $cfg:optConfig $(discharger)? $[only%$o]? $[[$args,*]]?)
+      `(tactic| simp_all!%$tk $(config)? $(discharger)? $[only%$o]? $[[$args,*]]?)
     else
-      `(tactic| simp_all%$tk $cfg:optConfig $(discharger)? $[only%$o]? $[[$args,*]]?)
+      `(tactic| simp_all%$tk $(config)? $(discharger)? $[only%$o]? $[[$args,*]]?)
     let { ctx, .. } ← mkSimpContext stx (eraseLocal := true)
       (kind := .simpAll) (ignoreStarArg := true)
     let (result?, stats) ← simpAll (← getMainGoal) ctx
@@ -81,11 +81,11 @@ where
 
 @[builtin_tactic dsimpTrace] def evalDSimpTrace : Tactic := fun stx =>
   match stx with
-  | `(tactic| dsimp?%$tk $[!%$bang]? $cfg:optConfig $[only%$o]? $[[$args,*]]? $(loc)?) => withSimpDiagnostics do
+  | `(tactic| dsimp?%$tk $[!%$bang]? $(config)? $[only%$o]? $[[$args,*]]? $(loc)?) => withSimpDiagnostics do
     let stx ← if bang.isSome then
-      `(tactic| dsimp!%$tk $cfg:optConfig $[only%$o]? $[[$args,*]]? $(loc)?)
+      `(tactic| dsimp!%$tk $(config)? $[only%$o]? $[[$args,*]]? $(loc)?)
     else
-      `(tactic| dsimp%$tk $cfg:optConfig $[only%$o]? $[[$args,*]]? $(loc)?)
+      `(tactic| dsimp%$tk $(config)? $[only%$o]? $[[$args,*]]? $(loc)?)
     let { ctx, simprocs, .. } ←
       withMainContext <| mkSimpContext stx (eraseLocal := false) (kind := .dsimp)
     let stats ← dsimpLocation' ctx simprocs <| (loc.map expandLocation).getD (.targets #[] true)

src/Lean/Elab/Tactic/Simpa.lean

@@ -31,9 +31,9 @@ deriving instance Repr for UseImplicitLambdaResult
 
 @[builtin_tactic Lean.Parser.Tactic.simpa] def evalSimpa : Tactic := fun stx => do
   match stx with
-  | `(tactic| simpa%$tk $[?%$squeeze]? $[!%$unfold]? $cfg:optConfig $(disch)? $[only%$only]?
+  | `(tactic| simpa%$tk $[?%$squeeze]? $[!%$unfold]? $(cfg)? $(disch)? $[only%$only]?
         $[[$args,*]]? $[using $usingArg]?) => Elab.Tactic.focus do withSimpDiagnostics do
-    let stx ← `(tactic| simp $cfg:optConfig $(disch)? $[only%$only]? $[[$args,*]]?)
+    let stx ← `(tactic| simp $(cfg)? $(disch)? $[only%$only]? $[[$args,*]]?)
     let { ctx, simprocs, dischargeWrapper } ←
       withMainContext <| mkSimpContext stx (eraseLocal := false)
     let ctx := if unfold.isSome then { ctx with config.autoUnfold := true } else ctx
@@ -96,11 +96,11 @@ deriving instance Repr for UseImplicitLambdaResult
         g.assumption; pure stats
       if tactic.simp.trace.get (← getOptions) || squeeze.isSome then
         let stx ← match ← mkSimpOnly stx stats.usedTheorems with
-          | `(tactic| simp $cfg:optConfig $(disch)? $[only%$only]? $[[$args,*]]?) =>
+          | `(tactic| simp $(cfg)? $(disch)? $[only%$only]? $[[$args,*]]?) =>
             if unfold.isSome then
-              `(tactic| simpa! $cfg:optConfig $(disch)? $[only%$only]? $[[$args,*]]? $[using $usingArg]?)
+              `(tactic| simpa! $(cfg)? $(disch)? $[only%$only]? $[[$args,*]]? $[using $usingArg]?)
             else
-              `(tactic| simpa $cfg:optConfig $(disch)? $[only%$only]? $[[$args,*]]? $[using $usingArg]?)
+              `(tactic| simpa $(cfg)? $(disch)? $[only%$only]? $[[$args,*]]? $[using $usingArg]?)
           | _ => unreachable!
         TryThis.addSuggestion tk stx (origSpan? := ← getRef)
       return stats.diag