cleanup

.github/workflows/check-prelude.yml

@@ -14,7 +14,6 @@ jobs:
           sparse-checkout: |
             src/Lean
             src/Std
-            src/lake/Lake
       - name: Check Prelude
         run: |
           failed_files=""
@@ -22,7 +21,7 @@ jobs:
             if ! grep -q "^prelude$" "$file"; then
               failed_files="$failed_files$file\n"
             fi
-          done < <(find src/Lean src/Std src/lake/Lake -name '*.lean' -print0)
+          done < <(find src/Lean src/Std -name '*.lean' -print0)
           if [ -n "$failed_files" ]; then
             echo -e "The following files should use 'prelude':\n$failed_files"
             exit 1

.github/workflows/labels-from-comments.yml

@@ -1,8 +1,7 @@
 # This workflow allows any user to add one of the `awaiting-review`, `awaiting-author`, `WIP`,
-# `release-ci`, or a `changelog-XXX` label by commenting on the PR or issue.
+# or `release-ci` labels by commenting on the PR or issue.
 # If any labels from the set {`awaiting-review`, `awaiting-author`, `WIP`} are added, other labels
 # from that set are removed automatically at the same time.
-# Similarly, if any `changelog-XXX` label is added, other `changelog-YYY` labels are removed.
 
 name: Label PR based on Comment
 
@@ -12,7 +11,7 @@ on:
 
 jobs:
   update-label:
-    if: github.event.issue.pull_request != null && (contains(github.event.comment.body, 'awaiting-review') || contains(github.event.comment.body, 'awaiting-author') || contains(github.event.comment.body, 'WIP') || contains(github.event.comment.body, 'release-ci') || contains(github.event.comment.body, 'changelog-'))
+    if: github.event.issue.pull_request != null && (contains(github.event.comment.body, 'awaiting-review') || contains(github.event.comment.body, 'awaiting-author') || contains(github.event.comment.body, 'WIP') || contains(github.event.comment.body, 'release-ci'))
     runs-on: ubuntu-latest
 
     steps:
@@ -21,14 +20,13 @@ jobs:
       with:
         github-token: ${{ secrets.GITHUB_TOKEN }}
         script: |
-          const { owner, repo, number: issue_number } = context.issue;
+          const { owner, repo, number: issue_number  } = context.issue;
           const commentLines = context.payload.comment.body.split('\r\n');
 
           const awaitingReview = commentLines.includes('awaiting-review');
           const awaitingAuthor = commentLines.includes('awaiting-author');
           const wip = commentLines.includes('WIP');
           const releaseCI = commentLines.includes('release-ci');
-          const changelogMatch = commentLines.find(line => line.startsWith('changelog-'));
 
           if (awaitingReview || awaitingAuthor || wip) {
             await github.rest.issues.removeLabel({ owner, repo, issue_number, name: 'awaiting-review' }).catch(() => {});
@@ -49,19 +47,3 @@ jobs:
           if (releaseCI) {
             await github.rest.issues.addLabels({ owner, repo, issue_number, labels: ['release-ci'] });
           }
-
-          if (changelogMatch) {
-            const changelogLabel = changelogMatch.trim();
-            const { data: existingLabels } = await github.rest.issues.listLabelsOnIssue({ owner, repo, issue_number });
-            const changelogLabels = existingLabels.filter(label => label.name.startsWith('changelog-'));
-
-            // Remove all other changelog labels
-            for (const label of changelogLabels) {
-              if (label.name !== changelogLabel) {
-                await github.rest.issues.removeLabel({ owner, repo, issue_number, name: label.name }).catch(() => {});
-              }
-            }
-
-            // Add the new changelog label
-            await github.rest.issues.addLabels({ owner, repo, issue_number, labels: [changelogLabel] });
-          }

.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@v7 # https://github.com/marketplace/actions/download-workflow-artifact
+        uses: dawidd6/action-download-artifact@v6 # https://github.com/marketplace/actions/download-workflow-artifact
         with:
           run_id: ${{ github.event.workflow_run.id }}
           path: artifacts
@@ -111,7 +111,7 @@ jobs:
 
       - name: 'Setup jq'
         if: ${{ steps.workflow-info.outputs.pullRequestNumber != '' }}
-        uses: dcarbone/install-jq-action@v3.0.1
+        uses: dcarbone/install-jq-action@v2.1.0
 
       # Check that the most recently nightly coincides with 'git merge-base HEAD master'
       - name: Check merge-base and nightly-testing-YYYY-MM-DD

RELEASES.md

@@ -8,299 +8,15 @@ 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.
 
-v4.16.0
+v4.15.0
 ----------
 
 Development in progress.
 
-v4.15.0
-----------
-
-Release candidate, release notes will be copied from the branch `releases/v4.15.0` once completed.
-
 v4.14.0
 ----------
 
-**Full Changelog**: https://github.com/leanprover/lean4/compare/v4.13.0...v4.14.0
-
-### Language features, tactics, and metaprograms
-
-* `structure` and `inductive` commands
-  * [#5517](https://github.com/leanprover/lean4/pull/5517) improves universe level inference for the resulting type of an `inductive` or `structure.` Recall that a `Prop`-valued inductive type is a syntactic subsingleton if it has at most one constructor and all the arguments to the constructor are in `Prop`. Such types have large elimination, so they could be defined in `Type` or `Prop` without any trouble. The way inference has changed is that if a type is a syntactic subsingleton with exactly one constructor, and the constructor has at least one parameter/field, then the `inductive`/`structure` command will prefer creating a `Prop` instead of a `Type`. The upshot is that the `: Prop` in `structure S : Prop` is often no longer needed. (With @arthur-adjedj).
-  * [#5842](https://github.com/leanprover/lean4/pull/5842) and [#5783](https://github.com/leanprover/lean4/pull/5783) implement a feature where the `structure` command can now define recursive inductive types:
-    ```lean
-    structure Tree where
-      n : Nat
-      children : Fin n → Tree
-
-    def Tree.size : Tree → Nat
-      | {n, children} => Id.run do
-        let mut s := 0
-        for h : i in [0 : n] do
-          s := s + (children ⟨i, h.2⟩).size
-        pure s
-    ```
-  * [#5814](https://github.com/leanprover/lean4/pull/5814) fixes a bug where Mathlib's `Type*` elaborator could lead to incorrect universe parameters with the `inductive` command.
-  * [#3152](https://github.com/leanprover/lean4/pull/3152) and [#5844](https://github.com/leanprover/lean4/pull/5844) fix bugs in default value processing for structure instance notation (with @arthur-adjedj).
-  * [#5399](https://github.com/leanprover/lean4/pull/5399) promotes instance synthesis order calculation failure from a soft error to a hard error.
-  * [#5542](https://github.com/leanprover/lean4/pull/5542) deprecates `:=` variants of `inductive` and `structure` (see breaking changes).
-
-* **Application elaboration improvements**
-  * [#5671](https://github.com/leanprover/lean4/pull/5671) makes `@[elab_as_elim]` require at least one discriminant, since otherwise there is no advantage to this alternative elaborator.
-  * [#5528](https://github.com/leanprover/lean4/pull/5528) enables field notation in explicit mode. The syntax `@x.f` elaborates as `@S.f` with `x` supplied to the appropriate parameter.
-  * [#5692](https://github.com/leanprover/lean4/pull/5692) modifies the dot notation resolution algorithm so that it can apply `CoeFun` instances. For example, Mathlib has `Multiset.card : Multiset α →+ Nat`, and now with `m : Multiset α`, the notation `m.card` resolves to `⇑Multiset.card m`.
-  * [#5658](https://github.com/leanprover/lean4/pull/5658) fixes a bug where 'don't know how to synthesize implicit argument' errors might have the incorrect local context when the eta arguments feature is activated.
-  * [#5933](https://github.com/leanprover/lean4/pull/5933) fixes a bug where `..` ellipses in patterns made use of optparams and autoparams.
-  * [#5770](https://github.com/leanprover/lean4/pull/5770) makes dot notation for structures resolve using *all* ancestors. Adds a *resolution order* for generalized field notation. This is the order of namespaces visited during resolution when trying to resolve names. The algorithm to compute a resolution order is the commonly used C3 linearization (used for example by Python), which when successful ensures that immediate parents' namespaces are considered before more distant ancestors' namespaces. By default we use a relaxed version of the algorithm that tolerates inconsistencies, but using `set_option structure.strictResolutionOrder true` makes inconsistent parent orderings into warnings.
-
-* **Recursion and induction principles**
-  * [#5619](https://github.com/leanprover/lean4/pull/5619) fixes functional induction principle generation to avoid over-eta-expanding in the preprocessing step.
-  * [#5766](https://github.com/leanprover/lean4/pull/5766) fixes structural nested recursion so that it is not confused when a nested type appears first.
-  * [#5803](https://github.com/leanprover/lean4/pull/5803) fixes a bug in functional induction principle generation when there are `let` bindings.
-  * [#5904](https://github.com/leanprover/lean4/pull/5904) improves functional induction principle generation to unfold aux definitions more carefully.
-  * [#5850](https://github.com/leanprover/lean4/pull/5850) refactors code for `Predefinition.Structural`.
-
-* **Error messages**
-  * [#5276](https://github.com/leanprover/lean4/pull/5276) fixes a bug in "type mismatch" errors that would structurally assign metavariables during the algorithm to expose differences.
-  * [#5919](https://github.com/leanprover/lean4/pull/5919) makes "type mismatch" errors add type ascriptions to expose differences for numeric literals.
-  * [#5922](https://github.com/leanprover/lean4/pull/5922) makes "type mismatch" errors expose differences in the bodies of functions and pi types.
-  * [#5888](https://github.com/leanprover/lean4/pull/5888) improves the error message for invalid induction alternative names in `match` expressions (@josojo).
-  * [#5719](https://github.com/leanprover/lean4/pull/5719) improves `calc` error messages.
-
-* [#5627](https://github.com/leanprover/lean4/pull/5627) and [#5663](https://github.com/leanprover/lean4/pull/5663) improve the **`#eval` command** and introduce some new features.
-  * Now results can be pretty printed if there is a `ToExpr` instance, which means **hoverable output**. If `ToExpr` fails, it then tries looking for a `Repr` or `ToString` instance like before. Setting `set_option eval.pp false` disables making use of `ToExpr` instances.
-  * There is now **auto-derivation** of `Repr` instances, enabled with the `pp.derive.repr` option (default to **true**). For example:
-    ```lean
-    inductive Baz
-    | a | b
-
-    #eval Baz.a
-    -- Baz.a
-    ```
-    It simply does `deriving instance Repr for Baz` when there's no way to represent `Baz`.
-  * The option `eval.type` controls whether or not to include the type in the output. For now the default is false.
-  * Now expressions such as `#eval do return 2`, where monad is unknown, work. It tries unifying the monad with `CommandElabM`, `TermElabM`, or `IO`.
-  * The classes `Lean.Eval` and `Lean.MetaEval` have been removed. These each used to be responsible for adapting monads and printing results. Now the `MonadEval` class is responsible for adapting monads for evaluation (it is similar to `MonadLift`, but instances are allowed to use default data when initializing state), and representing results is handled through a separate process.
-  * Error messages about failed instance synthesis are now more precise. Once it detects that a `MonadEval` class applies, then the error message will be specific about missing `ToExpr`/`Repr`/`ToString` instances.
-  * Fixes bugs where evaluating `MetaM` and `CoreM` wouldn't collect log messages.
-  * Fixes a bug where `let rec` could not be used in `#eval`.
-
-* `partial` definitions
-  * [#5780](https://github.com/leanprover/lean4/pull/5780) improves the error message when `partial` fails to prove a type is inhabited. Add delta deriving.
-  * [#5821](https://github.com/leanprover/lean4/pull/5821) gives `partial` inhabitation the ability to create local `Inhabited` instances from parameters.
-
-* **New tactic configuration syntax.** The configuration syntax for all core tactics has been given an upgrade. Rather than `simp (config := { contextual := true, maxSteps := 22})`, one can now write `simp +contextual (maxSteps := 22)`. Tactic authors can migrate by switching from `(config)?` to `optConfig` in tactic syntaxes and potentially deleting `mkOptionalNode` in elaborators. [#5883](https://github.com/leanprover/lean4/pull/5883), [#5898](https://github.com/leanprover/lean4/pull/5898),  [#5928](https://github.com/leanprover/lean4/pull/5928), and [#5932](https://github.com/leanprover/lean4/pull/5932). (Tactic authors, see breaking changes.)
-
-* `simp` tactic
-  * [#5632](https://github.com/leanprover/lean4/pull/5632) fixes the simpproc for `Fin` literals to reduce more consistently.
-  * [#5648](https://github.com/leanprover/lean4/pull/5648) fixes a bug in `simpa ... using t` where metavariables in `t` were not properly accounted for, and also improves the type mismatch error.
-  * [#5838](https://github.com/leanprover/lean4/pull/5838) fixes the docstring of `simp!` to actually talk about `simp!`.
-  * [#5870](https://github.com/leanprover/lean4/pull/5870) adds support for `attribute [simp ←]` (note the reverse direction). This adds the reverse of a theorem as a global simp theorem.
-
-* `decide` tactic
-  * [#5665](https://github.com/leanprover/lean4/pull/5665) adds `decide!` tactic for using kernel reduction (warning: this is renamed to `decide +kernel` in a future release).
-
-* `bv_decide` tactic
-  * [#5714](https://github.com/leanprover/lean4/pull/5714) adds inequality regression tests (@alexkeizer).
-  * [#5608](https://github.com/leanprover/lean4/pull/5608) adds `bv_toNat` tag for `toNat_ofInt` (@bollu).
-  * [#5618](https://github.com/leanprover/lean4/pull/5618) adds support for `at` in `ac_nf` and uses it in `bv_normalize` (@tobiasgrosser).
-  * [#5628](https://github.com/leanprover/lean4/pull/5628) adds udiv support.
-  * [#5635](https://github.com/leanprover/lean4/pull/5635) adds auxiliary bitblasters for negation and subtraction.
-  * [#5637](https://github.com/leanprover/lean4/pull/5637) adds more `getLsbD` bitblaster theory.
-  * [#5652](https://github.com/leanprover/lean4/pull/5652) adds umod support.
-  * [#5653](https://github.com/leanprover/lean4/pull/5653) adds performance benchmark for modulo.
-  * [#5655](https://github.com/leanprover/lean4/pull/5655) reduces error on `bv_check` to warning.
-  * [#5670](https://github.com/leanprover/lean4/pull/5670) adds `~~~(-x)` support.
-  * [#5673](https://github.com/leanprover/lean4/pull/5673) disables `ac_nf` by default.
-  * [#5675](https://github.com/leanprover/lean4/pull/5675) fixes context tracking in `bv_decide` counter example.
-  * [#5676](https://github.com/leanprover/lean4/pull/5676) adds an error when the LRAT proof is invalid.
-  * [#5781](https://github.com/leanprover/lean4/pull/5781) introduces uninterpreted symbols everywhere.
-  * [#5823](https://github.com/leanprover/lean4/pull/5823) adds `BitVec.sdiv` support.
-  * [#5852](https://github.com/leanprover/lean4/pull/5852) adds `BitVec.ofBool` support.
-  * [#5855](https://github.com/leanprover/lean4/pull/5855) adds `if` support.
-  * [#5869](https://github.com/leanprover/lean4/pull/5869) adds support for all the SMTLIB BitVec divison/remainder operations.
-  * [#5886](https://github.com/leanprover/lean4/pull/5886) adds embedded constraint substitution.
-  * [#5918](https://github.com/leanprover/lean4/pull/5918) fixes loose mvars bug in `bv_normalize`.
-  * Documentation:
-    * [#5636](https://github.com/leanprover/lean4/pull/5636) adds remarks about multiplication.
-
-* `conv` mode
-  * [#5861](https://github.com/leanprover/lean4/pull/5861) improves the `congr` conv tactic to handle "over-applied" functions.
-  * [#5894](https://github.com/leanprover/lean4/pull/5894) improves the `arg` conv tactic so that it can access more arguments and so that it can handle "over-applied" functions (it generates a specialized congruence lemma for the specific argument in question). Makes `arg 1` and `arg 2` apply to pi types in more situations. Adds negative indexing, for example `arg -2` is equivalent to the `lhs` tactic. Makes the `enter [...]` tactic show intermediate states like `rw`.
-
-* **Other tactics**
-  * [#4846](https://github.com/leanprover/lean4/pull/4846) fixes a bug where `generalize ... at *` would apply to implementation details (@ymherklotz).
-  * [#5730](https://github.com/leanprover/lean4/pull/5730) upstreams the `classical` tactic combinator.
-  * [#5815](https://github.com/leanprover/lean4/pull/5815) improves the error message when trying to unfold a local hypothesis that is not a local definition.
-  * [#5862](https://github.com/leanprover/lean4/pull/5862) and [#5863](https://github.com/leanprover/lean4/pull/5863) change how `apply` and `simp` elaborate, making them not disable error recovery. This improves hovers and completions when the term has elaboration errors.
-
-* `deriving` clauses
-  * [#5899](https://github.com/leanprover/lean4/pull/5899) adds declaration ranges for delta-derived instances.
-  * [#5265](https://github.com/leanprover/lean4/pull/5265) removes unused syntax in `deriving` clauses for providing arguments to deriving handlers (see breaking changes).
-
-* [#5065](https://github.com/leanprover/lean4/pull/5065) upstreams and updates `#where`, a command that reports the current scope information.
-
-* **Linters**
-  * [#5338](https://github.com/leanprover/lean4/pull/5338) makes the unused variables linter ignore variables defined in tactics by default now, avoiding performance bottlenecks.
-  * [#5644](https://github.com/leanprover/lean4/pull/5644) ensures that linters in general do not run on `#guard_msgs` itself.
-
-* **Metaprogramming interface**
-  * [#5720](https://github.com/leanprover/lean4/pull/5720) adds `pushGoal`/`pushGoals` and `popGoal` for manipulating the goal state. These are an alternative to `replaceMainGoal` and `getMainGoal`, and with them you don't need to worry about making sure nothing clears assigned metavariables from the goal list between assigning the main goal and using `replaceMainGoal`. Modifies `closeMainGoalUsing`, which is like a `TacticM` version of `liftMetaTactic`. Now the callback is run in a context where the main goal is removed from the goal list, and the callback is free to modify the goal list. Furthermore, the `checkUnassigned` argument has been replaced with `checkNewUnassigned`, which checks whether the value assigned to the goal has any *new* metavariables, relative to the start of execution of the callback. Modifies `withCollectingNewGoalsFrom` to take the `parentTag` argument explicitly rather than indirectly via `getMainTag`. Modifies `elabTermWithHoles` to optionally take `parentTag?`.
-  * [#5563](https://github.com/leanprover/lean4/pull/5563) fixes `getFunInfo` and `inferType` to use `withAtLeastTransparency` rather than `withTransparency`.
-  * [#5679](https://github.com/leanprover/lean4/pull/5679) fixes `RecursorVal.getInduct` to return the name of major argument’s type. This makes "structure eta" work for nested inductives.
-  * [#5681](https://github.com/leanprover/lean4/pull/5681) removes unused `mkRecursorInfoForKernelRec`.
-  * [#5686](https://github.com/leanprover/lean4/pull/5686) makes discrimination trees index the domains of foralls, for better performance of the simplify and type class search.
-  * [#5760](https://github.com/leanprover/lean4/pull/5760) adds `Lean.Expr.name?` recognizer for `Name` expressions.
-  * [#5800](https://github.com/leanprover/lean4/pull/5800) modifies `liftCommandElabM` to preserve more state, fixing an issue where using it would drop messages.
-  * [#5857](https://github.com/leanprover/lean4/pull/5857) makes it possible to use dot notation in `m!` strings, for example `m!"{.ofConstName n}"`.
-  * [#5841](https://github.com/leanprover/lean4/pull/5841) and [#5853](https://github.com/leanprover/lean4/pull/5853) record the complete list of `structure` parents in the `StructureInfo` environment extension.
-
-* **Other fixes or improvements**
-  * [#5566](https://github.com/leanprover/lean4/pull/5566) fixes a bug introduced in [#4781](https://github.com/leanprover/lean4/pull/4781) where heartbeat exceptions were no longer being handled properly. Now such exceptions are tagged with `runtime.maxHeartbeats` (@eric-wieser).
-  * [#5708](https://github.com/leanprover/lean4/pull/5708) modifies the proof objects produced by the proof-by-reflection tactics `ac_nf0` and `simp_arith` so that the kernel is less prone to reducing expensive atoms.
-  * [#5768](https://github.com/leanprover/lean4/pull/5768) adds a `#version` command that prints Lean's version information.
-  * [#5822](https://github.com/leanprover/lean4/pull/5822) fixes elaborator algorithms to match kernel algorithms for primitive projections (`Expr.proj`).
-  * [#5811](https://github.com/leanprover/lean4/pull/5811) improves the docstring for the `rwa` tactic.
-
-
-### Language server, widgets, and IDE extensions
-
-* [#5224](https://github.com/leanprover/lean4/pull/5224) fixes `WorkspaceClientCapabilities` to make `applyEdit` optional, in accordance with the LSP specification (@pzread).
-* [#5340](https://github.com/leanprover/lean4/pull/5340) fixes a server deadlock when shutting down the language server and a desync between client and language server after a file worker crash.
-* [#5560](https://github.com/leanprover/lean4/pull/5560) makes `initialize` and `builtin_initialize` participate in the call hierarchy and other requests.
-* [#5650](https://github.com/leanprover/lean4/pull/5650) makes references in attributes participate in the call hierarchy and other requests.
-* [#5666](https://github.com/leanprover/lean4/pull/5666) add auto-completion in tactic blocks without having to type the first character of the tactic, and adds tactic completion docs to tactic auto-completion items.
-* [#5677](https://github.com/leanprover/lean4/pull/5677) fixes several cases where goal states were not displayed in certain text cursor positions.
-* [#5707](https://github.com/leanprover/lean4/pull/5707) indicates deprecations in auto-completion items.
-* [#5736](https://github.com/leanprover/lean4/pull/5736), [#5752](https://github.com/leanprover/lean4/pull/5752), [#5763](https://github.com/leanprover/lean4/pull/5763), [#5802](https://github.com/leanprover/lean4/pull/5802), and [#5805](https://github.com/leanprover/lean4/pull/5805) fix various performance issues in the language server.
-* [#5801](https://github.com/leanprover/lean4/pull/5801) distinguishes theorem auto-completions from non-theorem auto-completions.
-
-### Pretty printing
-
-* [#5640](https://github.com/leanprover/lean4/pull/5640) fixes a bug where goal states in messages might print newlines as spaces.
-* [#5643](https://github.com/leanprover/lean4/pull/5643) adds option `pp.mvars.delayed` (default false), which when false causes delayed assignment metavariables to pretty print with what they are assigned to. Now `fun x : Nat => ?a` pretty prints as `fun x : Nat => ?a` rather than `fun x ↦ ?m.7 x`.
-* [#5711](https://github.com/leanprover/lean4/pull/5711) adds options `pp.mvars.anonymous` and `pp.mvars.levels`, which when false respectively cause expression metavariables and level metavariables to pretty print as `?_`.
-* [#5710](https://github.com/leanprover/lean4/pull/5710) adjusts the `⋯` elaboration warning to mention `pp.maxSteps`.
-
-* [#5759](https://github.com/leanprover/lean4/pull/5759) fixes the app unexpander for `sorryAx`.
-* [#5827](https://github.com/leanprover/lean4/pull/5827) improves accuracy of binder names in the signature pretty printer (like in output of `#check`). Also fixes the issue where consecutive hygienic names pretty print without a space separating them, so we now have `(x✝ y✝ : Nat)` rather than `(x✝y✝ : Nat)`.
-* [#5830](https://github.com/leanprover/lean4/pull/5830) makes sure all the core delaborators respond to `pp.explicit` when appropriate.
-* [#5639](https://github.com/leanprover/lean4/pull/5639) makes sure name literals use escaping when pretty printing.
-* [#5854](https://github.com/leanprover/lean4/pull/5854) adds delaborators for `<|>`, `<*>`, `>>`, `<*`, and `*>`.
-
-### Library
-
-* `Array`
-  * [#5687](https://github.com/leanprover/lean4/pull/5687) deprecates `Array.data`.
-  * [#5705](https://github.com/leanprover/lean4/pull/5705) uses a better default value for `Array.swapAt!`.
-  * [#5748](https://github.com/leanprover/lean4/pull/5748) moves `Array.mapIdx` lemmas to a new file.
-  * [#5749](https://github.com/leanprover/lean4/pull/5749) simplifies signature of `Array.mapIdx`.
-  * [#5758](https://github.com/leanprover/lean4/pull/5758) upstreams `Array.reduceOption`.
-  * [#5786](https://github.com/leanprover/lean4/pull/5786) adds simp lemmas for `Array.isEqv` and `BEq`.
-  * [#5796](https://github.com/leanprover/lean4/pull/5796) renames `Array.shrink` to `Array.take`, and relates it to `List.take`.
-  * [#5798](https://github.com/leanprover/lean4/pull/5798) upstreams `List.modify`, adds lemmas, relates to `Array.modify`.
-  * [#5799](https://github.com/leanprover/lean4/pull/5799) relates `Array.forIn` and `List.forIn`.
-  * [#5833](https://github.com/leanprover/lean4/pull/5833) adds `Array.forIn'`, and relates to `List`.
-  * [#5848](https://github.com/leanprover/lean4/pull/5848) fixes deprecations in `Init.Data.Array.Basic` to not recommend the deprecated constant.
-  * [#5895](https://github.com/leanprover/lean4/pull/5895) adds `LawfulBEq (Array α) ↔ LawfulBEq α`.
-  * [#5896](https://github.com/leanprover/lean4/pull/5896) moves `@[simp]` from `back_eq_back?` to `back_push`.
-  * [#5897](https://github.com/leanprover/lean4/pull/5897) renames `Array.back` to `back!`.
-
-* `List`
-  * [#5605](https://github.com/leanprover/lean4/pull/5605) removes `List.redLength`.
-  * [#5696](https://github.com/leanprover/lean4/pull/5696) upstreams `List.mapIdx` and adds lemmas.
-  * [#5697](https://github.com/leanprover/lean4/pull/5697) upstreams `List.foldxM_map`.
-  * [#5701](https://github.com/leanprover/lean4/pull/5701) renames `List.join` to `List.flatten`.
-  * [#5703](https://github.com/leanprover/lean4/pull/5703) upstreams `List.sum`.
-  * [#5706](https://github.com/leanprover/lean4/pull/5706) marks `prefix_append_right_inj` as a simp lemma.
-  * [#5716](https://github.com/leanprover/lean4/pull/5716) fixes `List.drop_drop` addition order.
-  * [#5731](https://github.com/leanprover/lean4/pull/5731) renames `List.bind` and `Array.concatMap` to `flatMap`.
-  * [#5732](https://github.com/leanprover/lean4/pull/5732) renames `List.pure` to `List.singleton`.
-  * [#5742](https://github.com/leanprover/lean4/pull/5742) upstreams `ne_of_mem_of_not_mem`.
-  * [#5743](https://github.com/leanprover/lean4/pull/5743) upstreams `ne_of_apply_ne`.
-  * [#5816](https://github.com/leanprover/lean4/pull/5816) adds more `List.modify` lemmas.
-  * [#5879](https://github.com/leanprover/lean4/pull/5879) renames `List.groupBy` to `splitBy`.
-  * [#5913](https://github.com/leanprover/lean4/pull/5913) relates `for` loops over `List` with `foldlM`.
-
-* `Nat`
-  * [#5694](https://github.com/leanprover/lean4/pull/5694) removes `instBEqNat`, which is redundant with `instBEqOfDecidableEq` but not defeq.
-  * [#5746](https://github.com/leanprover/lean4/pull/5746) deprecates `Nat.sum`.
-  * [#5785](https://github.com/leanprover/lean4/pull/5785) adds `Nat.forall_lt_succ` and variants.
-
-* Fixed width integers
-  * [#5323](https://github.com/leanprover/lean4/pull/5323) redefine unsigned fixed width integers in terms of `BitVec`.
-  * [#5735](https://github.com/leanprover/lean4/pull/5735) adds `UIntX.[val_ofNat, toBitVec_ofNat]`.
-  * [#5790](https://github.com/leanprover/lean4/pull/5790) defines `Int8`.
-  * [#5901](https://github.com/leanprover/lean4/pull/5901) removes native code for `UInt8.modn`.
-
-* `BitVec`
-  * [#5604](https://github.com/leanprover/lean4/pull/5604) completes `BitVec.[getMsbD|getLsbD|msb]` for shifts (@luisacicolini).
-  * [#5609](https://github.com/leanprover/lean4/pull/5609) adds lemmas for division when denominator is zero (@bollu).
-  * [#5620](https://github.com/leanprover/lean4/pull/5620) documents Bitblasting (@bollu)
-  * [#5623](https://github.com/leanprover/lean4/pull/5623) moves `BitVec.udiv/umod/sdiv/smod` after `add/sub/mul/lt` (@tobiasgrosser).
-  * [#5645](https://github.com/leanprover/lean4/pull/5645) defines `udiv` normal form to be `/`, resp. `umod` and `%` (@bollu).
-  * [#5646](https://github.com/leanprover/lean4/pull/5646) adds lemmas about arithmetic inequalities (@bollu).
-  * [#5680](https://github.com/leanprover/lean4/pull/5680) expands relationship with `toFin` (@tobiasgrosser).
-  * [#5691](https://github.com/leanprover/lean4/pull/5691) adds `BitVec.(getMSbD, msb)_(add, sub)` and `BitVec.getLsbD_sub` (@luisacicolini).
-  * [#5712](https://github.com/leanprover/lean4/pull/5712) adds `BitVec.[udiv|umod]_[zero|one|self]` (@tobiasgrosser).
-  * [#5718](https://github.com/leanprover/lean4/pull/5718) adds `BitVec.sdiv_[zero|one|self]` (@tobiasgrosser).
-  * [#5721](https://github.com/leanprover/lean4/pull/5721) adds `BitVec.(msb, getMsbD, getLsbD)_(neg, abs)` (@luisacicolini).
-  * [#5772](https://github.com/leanprover/lean4/pull/5772) adds `BitVec.toInt_sub`, simplifies `BitVec.toInt_neg` (@tobiasgrosser).
-  * [#5778](https://github.com/leanprover/lean4/pull/5778) prove that `intMin` the smallest signed bitvector (@alexkeizer).
-  * [#5851](https://github.com/leanprover/lean4/pull/5851) adds `(msb, getMsbD)_twoPow` (@luisacicolini).
-  * [#5858](https://github.com/leanprover/lean4/pull/5858) adds `BitVec.[zero_ushiftRight|zero_sshiftRight|zero_mul]` and cleans up BVDecide (@tobiasgrosser).
-  * [#5865](https://github.com/leanprover/lean4/pull/5865) adds `BitVec.(msb, getMsbD)_concat` (@luisacicolini).
-  * [#5881](https://github.com/leanprover/lean4/pull/5881) adds `Hashable (BitVec n)`
-
-* `String`/`Char`
-  * [#5728](https://github.com/leanprover/lean4/pull/5728) upstreams `String.dropPrefix?`.
-  * [#5745](https://github.com/leanprover/lean4/pull/5745) changes `String.dropPrefix?` signature.
-  * [#5747](https://github.com/leanprover/lean4/pull/5747) adds `Hashable Char` instance
-
-* `HashMap`
-  * [#5880](https://github.com/leanprover/lean4/pull/5880) adds interim implementation of `HashMap.modify`/`alter`
-
-* **Other**
-  * [#5704](https://github.com/leanprover/lean4/pull/5704) removes `@[simp]` from `Option.isSome_eq_isSome`.
-  * [#5739](https://github.com/leanprover/lean4/pull/5739) upstreams material on `Prod`.
-  * [#5740](https://github.com/leanprover/lean4/pull/5740) moves `Antisymm` to `Std.Antisymm`.
-  * [#5741](https://github.com/leanprover/lean4/pull/5741) upstreams basic material on `Sum`.
-  * [#5756](https://github.com/leanprover/lean4/pull/5756) adds `Nat.log2_two_pow` (@spinylobster).
-  * [#5892](https://github.com/leanprover/lean4/pull/5892) removes duplicated `ForIn` instances.
-  * [#5900](https://github.com/leanprover/lean4/pull/5900) removes `@[simp]` from `Sum.forall` and `Sum.exists`.
-  * [#5812](https://github.com/leanprover/lean4/pull/5812) removes redundant `Decidable` assumptions (@FR-vdash-bot).
-
-### Compiler, runtime, and FFI
-
-* [#5685](https://github.com/leanprover/lean4/pull/5685) fixes help message flags, removes the `-f` flag and adds the `-g` flag (@James-Oswald).
-* [#5930](https://github.com/leanprover/lean4/pull/5930) adds `--short-version` (`-V`) option to display short version (@juhp).
-* [#5144](https://github.com/leanprover/lean4/pull/5144) switches all 64-bit platforms over to consistently using GMP for bignum arithmetic.
-* [#5753](https://github.com/leanprover/lean4/pull/5753) raises the minimum supported Windows version to Windows 10 1903 (released May 2019).
-
-### Lake
-
-* [#5715](https://github.com/leanprover/lean4/pull/5715) changes `lake new math` to use `autoImplicit false` (@eric-wieser).
-* [#5688](https://github.com/leanprover/lean4/pull/5688) makes `Lake` not create core aliases in the `Lake` namespace.
-* [#5924](https://github.com/leanprover/lean4/pull/5924) adds a `text` option for `buildFile*` utilities.
-* [#5789](https://github.com/leanprover/lean4/pull/5789) makes `lake init` not `git init` when inside git work tree (@haoxins).
-* [#5684](https://github.com/leanprover/lean4/pull/5684) has Lake update a package's `lean-toolchain` file on `lake update` if it finds the package's direct dependencies use a newer compatible toolchain. To skip this step, use the `--keep-toolchain` CLI option. (See breaking changes.)
-* [#6218](https://github.com/leanprover/lean4/pull/6218) makes Lake no longer automatically fetch GitHub cloud releases if the package build directory is already present (mirroring the behavior of the Reservoir cache). This prevents the cache from clobbering existing prebuilt artifacts. Users can still manually fetch the cache and clobber the build directory by running `lake build <pkg>:release`.
-* [#6231](https://github.com/leanprover/lean4/pull/6231) improves the errors Lake produces when it fails to fetch a dependency from Reservoir. If the package is not indexed, it will produce a suggestion about how to require it from GitHub.
-
-### Documentation
-
-* [#5617](https://github.com/leanprover/lean4/pull/5617) fixes MSYS2 build instructions.
-* [#5725](https://github.com/leanprover/lean4/pull/5725) points out that `OfScientific` is called with raw literals (@eric-wieser).
-* [#5794](https://github.com/leanprover/lean4/pull/5794) adds a stub for application ellipsis notation (@eric-wieser).
-
-### Breaking changes
-
-* The syntax for providing arguments to deriving handlers has been removed, which was not used by any major Lean projects in the ecosystem. As a result, the  `applyDerivingHandlers` now takes one fewer argument, `registerDerivingHandlerWithArgs` is now simply `registerDerivingHandler`, `DerivingHandler` no longer includes the unused parameter, and `DerivingHandlerNoArgs` has been deprecated. To migrate code, delete the unused `none` argument and use `registerDerivingHandler` and `DerivingHandler`. ([#5265](https://github.com/leanprover/lean4/pull/5265))
-* The minimum supported Windows version has been raised to Windows 10 1903, released May 2019. ([#5753](https://github.com/leanprover/lean4/pull/5753))
-* The `--lean` CLI option for `lake` was removed. Use the `LEAN` environment variable instead. ([#5684](https://github.com/leanprover/lean4/pull/5684))
-* The `inductive ... :=`, `structure ... :=`, and `class ... :=` syntaxes have been deprecated in favor of the `... where` variants. The old syntax produces a warning, controlled by the `linter.deprecated` option. ([#5542](https://github.com/leanprover/lean4/pull/5542))
-* The generated tactic configuration elaborators now land in `TacticM` to make use of the current recovery state. Commands that wish to elaborate configurations should now use `declare_command_config_elab` instead of `declare_config_elab` to get an elaborator landing in `CommandElabM`. Syntaxes should migrate to `optConfig` instead of `(config)?`, but the elaborators are reverse compatible. ([#5883](https://github.com/leanprover/lean4/pull/5883))
-
+Release candidate, release notes will be copied from the branch `releases/v4.14.0` once completed.
 
 v4.13.0
 ----------
@@ -372,7 +88,7 @@ v4.13.0
   * [#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)
+  * [#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`.

debug.log

@@ -0,0 +1 @@
+[0829/202002.254:ERROR:crashpad_client_win.cc(868)] not connected

doc/dev/bootstrap.md

@@ -103,21 +103,10 @@ your PR using rebase merge, bypassing the merge queue.
 As written above, changes in meta code in the current stage usually will only
 affect later stages. This is an issue in two specific cases.
 
-* For the special case of *quotations*, it is desirable to have changes in builtin parsers affect them immediately: when the changes in the parser become active in the next stage, builtin macros implemented via quotations should generate syntax trees compatible with the new parser, and quotation patterns in builtin macros and elaborators should be able to match syntax created by the new parser and macros.
-  Since quotations capture the syntax tree structure during execution of the current stage and turn it into code for the next stage, we need to run the current stage's builtin parsers in quotations via the interpreter for this to work.
-  Caveats:
-  * We activate this behavior by default when building stage 1 by setting `-Dinternal.parseQuotWithCurrentStage=true`.
-    We force-disable it inside `macro/macro_rules/elab/elab_rules` via `suppressInsideQuot` as they are guaranteed not to run in the next stage and may need to be run in the current one, so the stage 0 parser is the correct one to use for them.
-    It may be necessary to extend this disabling to functions that contain quotations and are (exclusively) used by one of the mentioned commands. A function using quotations should never be used by both builtin and non-builtin macros/elaborators. Example: https://github.com/leanprover/lean4/blob/f70b7e5722da6101572869d87832494e2f8534b7/src/Lean/Elab/Tactic/Config.lean#L118-L122
-  * The parser needs to be reachable via an `import` statement, otherwise the version of the previous stage will silently be used.
-  * Only the parser code (`Parser.fn`) is affected; all metadata such as leading tokens is taken from the previous stage.
-
-  For an example, see https://github.com/leanprover/lean4/commit/f9dcbbddc48ccab22c7674ba20c5f409823b4cc1#diff-371387aed38bb02bf7761084fd9460e4168ae16d1ffe5de041b47d3ad2d22422R13
-
 * For *non-builtin* meta code such as `notation`s or `macro`s in
   `Notation.lean`, we expect changes to affect the current file and all later
   files of the same stage immediately, just like outside the stdlib. To ensure
-  this, we build stage 1 using `-Dinterpreter.prefer_native=false` -
+  this, we need to build the stage using `-Dinterpreter.prefer_native=false` -
   otherwise, when executing a macro, the interpreter would notice that there is
   already a native symbol available for this function and run it instead of the
   new IR, but the symbol is from the previous stage!
@@ -135,11 +124,26 @@ affect later stages. This is an issue in two specific cases.
   further stages (e.g. after an `update-stage0`) will then need to be compiled
   with the flag set to `false` again since they will expect the new signature.
 
-  When enabling `prefer_native`, we usually want to *disable* `parseQuotWithCurrentStage` as it would otherwise make quotations use the interpreter after all.
-  However, there is a specific case where we want to set both options to `true`: when we make changes to a non-builtin parser like `simp` that has a builtin elaborator, we cannot have the new parser be active outside of quotations in stage 1 as the builtin elaborator from stage 0 would not understand them; on the other hand, we need quotations in e.g. the builtin `simp` elaborator to produce the new syntax in the next stage.
-  As this issue usually affects only tactics, enabling `debug.byAsSorry` instead of `prefer_native` can be a simpler solution.
+  For an example, see https://github.com/leanprover/lean4/commit/da4c46370d85add64ef7ca5e7cc4638b62823fbb.
 
-  For a `prefer_native` example, see https://github.com/leanprover/lean4/commit/da4c46370d85add64ef7ca5e7cc4638b62823fbb.
+* For the special case of *quotations*, it is desirable to have changes in
+  built-in parsers affect them immediately: when the changes in the parser
+  become active in the next stage, macros implemented via quotations should
+  generate syntax trees compatible with the new parser, and quotation patterns
+  in macro and elaborators should be able to match syntax created by the new
+  parser and macros. Since quotations capture the syntax tree structure during
+  execution of the current stage and turn it into code for the next stage, we
+  need to run the current stage's built-in parsers in quotation via the
+  interpreter for this to work. Caveats:
+  * Since interpreting full parsers is not nearly as cheap and we rarely change
+    built-in syntax, this needs to be opted in using `-Dinternal.parseQuotWithCurrentStage=true`.
+  * The parser needs to be reachable via an `import` statement, otherwise the
+    version of the previous stage will silently be used.
+  * Only the parser code (`Parser.fn`) is affected; all metadata such as leading
+    tokens is taken from the previous stage.
+
+  For an example, see https://github.com/leanprover/lean4/commit/f9dcbbddc48ccab22c7674ba20c5f409823b4cc1#diff-371387aed38bb02bf7761084fd9460e4168ae16d1ffe5de041b47d3ad2d22422
+  (from before the flag defaulted to `false`).
 
 To modify either of these flags both for building and editing the stdlib, adjust
 the code in `stage0/src/stdlib_flags.h`. The flags will automatically be reset

doc/examples/interp.lean

@@ -12,17 +12,17 @@ Remark: this example is based on an example found in the Idris manual.
 Vectors
 --------
 
-A `Vec` is a list of size `n` whose elements belong to a type `α`.
+A `Vector` is a list of size `n` whose elements belong to a type `α`.
 -/
 
-inductive Vec (α : Type u) : Nat → Type u
-  | nil : Vec α 0
-  | cons : α → Vec α n → Vec α (n+1)
+inductive Vector (α : Type u) : Nat → Type u
+  | nil : Vector α 0
+  | cons : α → Vector α n → Vector α (n+1)
 
 /-!
-We can overload the `List.cons` notation `::` and use it to create `Vec`s.
+We can overload the `List.cons` notation `::` and use it to create `Vector`s.
 -/
-infix:67 " :: " => Vec.cons
+infix:67 " :: " => Vector.cons
 
 /-!
 Now, we define the types of our simple functional language.
@@ -50,11 +50,11 @@ the builtin instance for `Add Int` as the solution.
 /-!
 Expressions are indexed by the types of the local variables, and the type of the expression itself.
 -/
-inductive HasType : Fin n → Vec Ty n → Ty → Type where
+inductive HasType : Fin n → Vector Ty n → Ty → Type where
   | stop : HasType 0 (ty :: ctx) ty
   | pop  : HasType k ctx ty → HasType k.succ (u :: ctx) ty
 
-inductive Expr : Vec Ty n → Ty → Type where
+inductive Expr : Vector Ty n → Ty → Type where
   | var   : HasType i ctx ty → Expr ctx ty
   | val   : Int → Expr ctx Ty.int
   | lam   : Expr (a :: ctx) ty → Expr ctx (Ty.fn a ty)
@@ -102,8 +102,8 @@ indexed over the types in scope. Since an environment is just another form of li
 to the vector of local variable types, we overload again the notation `::` so that we can use the usual list syntax.
 Given a proof that a variable is defined in the context, we can then produce a value from the environment.
 -/
-inductive Env : Vec Ty n → Type where
-  | nil  : Env Vec.nil
+inductive Env : Vector Ty n → Type where
+  | nil  : Env Vector.nil
   | cons : Ty.interp a → Env ctx → Env (a :: ctx)
 
 infix:67 " :: " => Env.cons

doc/examples/tc.lean

@@ -82,7 +82,9 @@ theorem Expr.typeCheck_correct (h₁ : HasType e ty) (h₂ : e.typeCheck ≠ .un
 /-!
 Now, we prove that if `Expr.typeCheck e` returns `Maybe.unknown`, then forall `ty`, `HasType e ty` does not hold.
 The notation `e.typeCheck` is sugar for `Expr.typeCheck e`. Lean can infer this because we explicitly said that `e` has type `Expr`.
-The proof is by induction on `e` and case analysis. Note that the tactic `simp [typeCheck]` is applied to all goal generated by the `induction` tactic, and closes
+The proof is by induction on `e` and case analysis. The tactic `rename_i` is used to rename "inaccessible" variables.
+We say a variable is inaccessible if it is introduced by a tactic (e.g., `cases`) or has been shadowed by another variable introduced
+by the user. Note that the tactic `simp [typeCheck]` is applied to all goal generated by the `induction` tactic, and closes
 the cases corresponding to the constructors `Expr.nat` and `Expr.bool`.
 -/
 theorem Expr.typeCheck_complete {e : Expr} : e.typeCheck = .unknown → ¬ HasType e ty := by

doc/examples/test_single.sh

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

doc/lexical_structure.md

@@ -128,16 +128,16 @@ Numeric literals can be specified in various bases.
 
 ```
    numeral    : numeral10 | numeral2 | numeral8 | numeral16
-   numeral10  : [0-9]+ ("_"+ [0-9]+)*
-   numeral2   : "0" [bB] ("_"* [0-1]+)+
-   numeral8   : "0" [oO] ("_"* [0-7]+)+
-   numeral16  : "0" [xX] ("_"* hex_char+)+
+   numeral10  : [0-9]+
+   numeral2   : "0" [bB] [0-1]+
+   numeral8   : "0" [oO] [0-7]+
+   numeral16  : "0" [xX] hex_char+
 ```
 
 Floating point literals are also possible with optional exponent:
 
 ```
-   float    : numeral10 "." numeral10? [eE[+-]numeral10]
+   float    : [0-9]+ "." [0-9]+ [[eE[+-][0-9]+]
 ```
 
 For example:
@@ -147,7 +147,6 @@ constant w : Int := 55
 constant x : Nat := 26085
 constant y : Nat := 0x65E5
 constant z : Float := 2.548123e-05
-constant b : Bool := 0b_11_01_10_00
 ```
 
 Note: that negative numbers are created by applying the "-" negation prefix operator to the number, for example:

doc/monads/readers.lean

@@ -139,7 +139,7 @@ You might be wondering, how does the context actually move through the `ReaderM`
 add an input argument to a function by modifying its return type?  There is a special command in
 Lean that will show you the reduced types:
 -/
-#reduce (types := true) ReaderM Environment String   -- Environment → String
+#reduce ReaderM Environment String   -- Environment → String
 /-!
 And you can see here that this type is actually a function!  It's a function that takes an
 `Environment` as input and returns a `String`.
@@ -196,4 +196,4 @@ entirely.
 
 Now it's time to move on to [StateM Monad](states.lean.md) which is like a `ReaderM` that is
 also updatable.
--/
+-/

script/mathlib-bench

@@ -1,12 +0,0 @@
-#! /bin/env bash
-# Open a Mathlib4 PR for benchmarking a given Lean 4 PR
-
-set -euo pipefail
-
-[ $# -eq 1 ] || (echo "usage: $0 <lean4 PR #>"; exit 1)
-
-LEAN_PR=$1
-PR_RESPONSE=$(gh api repos/leanprover-community/mathlib4/pulls -X POST -f head=lean-pr-testing-$LEAN_PR -f base=nightly-testing -f title="leanprover/lean4#$LEAN_PR benchmarking" -f draft=true -f body="ignore me")
-PR_NUMBER=$(echo "$PR_RESPONSE" | jq '.number')
-echo "opened https://github.com/leanprover-community/mathlib4/pull/$PR_NUMBER"
-gh api repos/leanprover-community/mathlib4/issues/$PR_NUMBER/comments -X POST -f body="!bench" > /dev/null

src/CMakeLists.txt

@@ -10,7 +10,7 @@ endif()
 include(ExternalProject)
 project(LEAN CXX C)
 set(LEAN_VERSION_MAJOR 4)
-set(LEAN_VERSION_MINOR 16)
+set(LEAN_VERSION_MINOR 15)
 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'")
@@ -51,8 +51,6 @@ option(LLVM               "LLVM"               OFF)
 option(USE_GITHASH        "GIT_HASH"           ON)
 # When ON we install LICENSE files to CMAKE_INSTALL_PREFIX
 option(INSTALL_LICENSE "INSTALL_LICENSE" ON)
-# When ON we install a copy of cadical
-option(INSTALL_CADICAL "Install a copy of cadical" ON)
 # When ON thread storage is automatically finalized, it assumes platform support pthreads.
 # This option is important when using Lean as library that is invoked from a different programming language (e.g., Haskell).
 option(AUTO_THREAD_FINALIZATION "AUTO_THREAD_FINALIZATION" ON)
@@ -122,7 +120,7 @@ if(${CMAKE_SYSTEM_NAME} MATCHES "Emscripten")
     # From https://emscripten.org/docs/compiling/WebAssembly.html#backends:
     # > The simple and safe thing is to pass all -s flags at both compile and link time.
     set(EMSCRIPTEN_SETTINGS "-s ALLOW_MEMORY_GROWTH=1 -fwasm-exceptions -pthread -flto")
-    string(APPEND LEANC_EXTRA_CC_FLAGS " -pthread")
+    string(APPEND LEANC_EXTRA_FLAGS " -pthread")
     string(APPEND LEAN_EXTRA_CXX_FLAGS " -D LEAN_EMSCRIPTEN ${EMSCRIPTEN_SETTINGS}")
     string(APPEND LEAN_EXTRA_LINKER_FLAGS " ${EMSCRIPTEN_SETTINGS}")
 endif()
@@ -157,11 +155,11 @@ if ((${MULTI_THREAD} MATCHES "ON") AND (${CMAKE_SYSTEM_NAME} MATCHES "Darwin"))
 endif ()
 
 # We want explicit stack probes in huge Lean stack frames for robust stack overflow detection
-string(APPEND LEANC_EXTRA_CC_FLAGS " -fstack-clash-protection")
+string(APPEND LEANC_EXTRA_FLAGS " -fstack-clash-protection")
 
 # This makes signed integer overflow guaranteed to match 2's complement.
 string(APPEND CMAKE_CXX_FLAGS " -fwrapv")
-string(APPEND LEANC_EXTRA_CC_FLAGS " -fwrapv")
+string(APPEND LEANC_EXTRA_FLAGS " -fwrapv")
 
 if(NOT MULTI_THREAD)
   message(STATUS "Disabled multi-thread support, it will not be safe to run multiple threads in parallel")
@@ -451,7 +449,7 @@ if(${CMAKE_SYSTEM_NAME} MATCHES "Linux")
     string(APPEND TOOLCHAIN_SHARED_LINKER_FLAGS " -Wl,-Bsymbolic")
   endif()
   string(APPEND CMAKE_CXX_FLAGS " -fPIC -ftls-model=initial-exec")
-  string(APPEND LEANC_EXTRA_CC_FLAGS " -fPIC")
+  string(APPEND LEANC_EXTRA_FLAGS " -fPIC")
   string(APPEND TOOLCHAIN_SHARED_LINKER_FLAGS " -Wl,-rpath=\\$$ORIGIN/..:\\$$ORIGIN")
   string(APPEND LAKESHARED_LINKER_FLAGS " -Wl,--whole-archive ${CMAKE_BINARY_DIR}/lib/temp/libLake.a.export -Wl,--no-whole-archive")
   string(APPEND CMAKE_EXE_LINKER_FLAGS " -Wl,-rpath=\\\$ORIGIN/../lib:\\\$ORIGIN/../lib/lean")
@@ -464,7 +462,7 @@ elseif(${CMAKE_SYSTEM_NAME} MATCHES "Darwin")
   string(APPEND CMAKE_EXE_LINKER_FLAGS " -Wl,-rpath,@executable_path/../lib -Wl,-rpath,@executable_path/../lib/lean")
 elseif(${CMAKE_SYSTEM_NAME} MATCHES "Emscripten")
   string(APPEND CMAKE_CXX_FLAGS " -fPIC")
-  string(APPEND LEANC_EXTRA_CC_FLAGS " -fPIC")
+  string(APPEND LEANC_EXTRA_FLAGS " -fPIC")
 elseif(${CMAKE_SYSTEM_NAME} MATCHES "Windows")
   string(APPEND LAKESHARED_LINKER_FLAGS " -Wl,--out-implib,${CMAKE_BINARY_DIR}/lib/lean/libLake_shared.dll.a -Wl,--whole-archive ${CMAKE_BINARY_DIR}/lib/temp/libLake.a.export -Wl,--no-whole-archive")
 endif()
@@ -479,7 +477,7 @@ if(NOT(${CMAKE_SYSTEM_NAME} MATCHES "Windows") AND NOT(${CMAKE_SYSTEM_NAME} MATC
   string(APPEND CMAKE_EXE_LINKER_FLAGS " -rdynamic")
   # hide all other symbols
   string(APPEND CMAKE_CXX_FLAGS " -fvisibility=hidden -fvisibility-inlines-hidden")
-  string(APPEND LEANC_EXTRA_CC_FLAGS " -fvisibility=hidden")
+  string(APPEND LEANC_EXTRA_FLAGS " -fvisibility=hidden")
 endif()
 
 # On Windows, add bcrypt for random number generation
@@ -544,10 +542,9 @@ include_directories(${CMAKE_BINARY_DIR}/include)  # config.h etc., "public" head
 string(TOUPPER "${CMAKE_BUILD_TYPE}" uppercase_CMAKE_BUILD_TYPE)
 string(APPEND LEANC_OPTS " ${CMAKE_CXX_FLAGS_${uppercase_CMAKE_BUILD_TYPE}}")
 
-# Do embed flag for finding system headers and libraries in dev builds
+# Do embed flag for finding system libraries in dev builds
 if(CMAKE_OSX_SYSROOT AND NOT LEAN_STANDALONE)
-  string(APPEND LEANC_EXTRA_CC_FLAGS " ${CMAKE_CXX_SYSROOT_FLAG}${CMAKE_OSX_SYSROOT}")
-  string(APPEND LEAN_EXTRA_LINKER_FLAGS " ${CMAKE_CXX_SYSROOT_FLAG}${CMAKE_OSX_SYSROOT}")
+  string(APPEND LEANC_EXTRA_FLAGS " ${CMAKE_CXX_SYSROOT_FLAG}${CMAKE_OSX_SYSROOT}")
 endif()
 
 add_subdirectory(initialize)
@@ -619,7 +616,7 @@ else()
     OUTPUT_NAME leancpp)
 endif()
 
-if((${STAGE} GREATER 0) AND CADICAL AND INSTALL_CADICAL)
+if((${STAGE} GREATER 0) AND CADICAL)
   add_custom_target(copy-cadical
     COMMAND cmake -E copy_if_different "${CADICAL}" "${CMAKE_BINARY_DIR}/bin/cadical${CMAKE_EXECUTABLE_SUFFIX}")
   add_dependencies(leancpp copy-cadical)
@@ -741,7 +738,7 @@ file(COPY ${LEAN_SOURCE_DIR}/bin/leanmake DESTINATION ${CMAKE_BINARY_DIR}/bin)
 
 install(DIRECTORY "${CMAKE_BINARY_DIR}/bin/" USE_SOURCE_PERMISSIONS DESTINATION bin)
 
-if (${STAGE} GREATER 0 AND CADICAL AND INSTALL_CADICAL)
+if (${STAGE} GREATER 0 AND CADICAL)
   install(PROGRAMS "${CADICAL}" DESTINATION bin)
 endif()
 

src/Init/Data.lean

@@ -21,7 +21,6 @@ import Init.Data.Fin
 import Init.Data.UInt
 import Init.Data.SInt
 import Init.Data.Float
-import Init.Data.Float32
 import Init.Data.Option
 import Init.Data.Ord
 import Init.Data.Random
@@ -44,4 +43,3 @@ import Init.Data.Zero
 import Init.Data.NeZero
 import Init.Data.Function
 import Init.Data.RArray
-import Init.Data.Vector

src/Init/Data/Array.lean

@@ -19,6 +19,3 @@ import Init.Data.Array.GetLit
 import Init.Data.Array.MapIdx
 import Init.Data.Array.Set
 import Init.Data.Array.Monadic
-import Init.Data.Array.FinRange
-import Init.Data.Array.Perm
-import Init.Data.Array.Find

src/Init/Data/Array/Attach.lean

@@ -10,13 +10,12 @@ import Init.Data.List.Attach
 
 namespace Array
 
-/--
-`O(n)`. Partial map. If `f : Π a, P a → β` is a partial function defined on
-`a : α` satisfying `P`, then `pmap f l h` is essentially the same as `map f l`
-but is defined only when all members of `l` satisfy `P`, using the proof
-to apply `f`.
+/-- `O(n)`. Partial map. If `f : Π a, P a → β` is a partial function defined on
+  `a : α` satisfying `P`, then `pmap f l h` is essentially the same as `map f l`
+  but is defined only when all members of `l` satisfy `P`, using the proof
+  to apply `f`.
 
-We replace this at runtime with a more efficient version via the `csimp` lemma `pmap_eq_pmapImpl`.
+We replace this at runtime with a more efficient version via
 -/
 def pmap {P : α → Prop} (f : ∀ a, P a → β) (l : Array α) (H : ∀ a ∈ l, P a) : Array β :=
   (l.toList.pmap f (fun a m => H a (mem_def.mpr m))).toArray
@@ -74,17 +73,6 @@ Unsafe implementation of `attachWith`, taking advantage of the fact that the rep
   intro a m h₁ h₂
   congr
 
-@[simp] theorem pmap_empty {P : α → Prop} (f : ∀ a, P a → β) : pmap f #[] (by simp) = #[] := rfl
-
-@[simp] theorem pmap_push {P : α → Prop} (f : ∀ a, P a → β) (a : α) (l : Array α) (h : ∀ b ∈ l.push a, P b) :
-    pmap f (l.push a) h =
-      (pmap f l (fun a m => by simp at h; exact h a (.inl m))).push (f a (h a (by simp))) := by
-  simp [pmap]
-
-@[simp] theorem attach_empty : (#[] : Array α).attach = #[] := rfl
-
-@[simp] theorem attachWith_empty {P : α → Prop} (H : ∀ x ∈ #[], P x) : (#[] : Array α).attachWith P H = #[] := rfl
-
 @[simp] theorem _root_.List.attachWith_mem_toArray {l : List α} :
     l.attachWith (fun x => x ∈ l.toArray) (fun x h => by simpa using h) =
       l.attach.map fun ⟨x, h⟩ => ⟨x, by simpa using h⟩ := by
@@ -92,353 +80,6 @@ Unsafe implementation of `attachWith`, taking advantage of the fact that the rep
   apply List.pmap_congr_left
   simp
 
-@[simp]
-theorem pmap_eq_map (p : α → Prop) (f : α → β) (l : Array α) (H) :
-    @pmap _ _ p (fun a _ => f a) l H = map f l := by
-  cases l; simp
-
-theorem pmap_congr_left {p q : α → Prop} {f : ∀ a, p a → β} {g : ∀ a, q a → β} (l : Array α) {H₁ H₂}
-    (h : ∀ a ∈ l, ∀ (h₁ h₂), f a h₁ = g a h₂) : pmap f l H₁ = pmap g l H₂ := by
-  cases l
-  simp only [mem_toArray] at h
-  simp only [List.pmap_toArray, mk.injEq]
-  rw [List.pmap_congr_left _ h]
-
-theorem map_pmap {p : α → Prop} (g : β → γ) (f : ∀ a, p a → β) (l H) :
-    map g (pmap f l H) = pmap (fun a h => g (f a h)) l H := by
-  cases l
-  simp [List.map_pmap]
-
-theorem pmap_map {p : β → Prop} (g : ∀ b, p b → γ) (f : α → β) (l H) :
-    pmap g (map f l) H = pmap (fun a h => g (f a) h) l fun _ h => H _ (mem_map_of_mem _ h) := by
-  cases l
-  simp [List.pmap_map]
-
-theorem attach_congr {l₁ l₂ : Array α} (h : l₁ = l₂) :
-    l₁.attach = l₂.attach.map (fun x => ⟨x.1, h ▸ x.2⟩) := by
-  subst h
-  simp
-
-theorem attachWith_congr {l₁ l₂ : Array α} (w : l₁ = l₂) {P : α → Prop} {H : ∀ x ∈ l₁, P x} :
-    l₁.attachWith P H = l₂.attachWith P fun _ h => H _ (w ▸ h) := by
-  subst w
-  simp
-
-@[simp] theorem attach_push {a : α} {l : Array α} :
-    (l.push a).attach =
-      (l.attach.map (fun ⟨x, h⟩ => ⟨x, mem_push_of_mem a h⟩)).push ⟨a, by simp⟩ := by
-  cases l
-  rw [attach_congr (List.push_toArray _ _)]
-  simp [Function.comp_def]
-
-@[simp] theorem attachWith_push {a : α} {l : Array α} {P : α → Prop} {H : ∀ x ∈ l.push a, P x} :
-    (l.push a).attachWith P H =
-      (l.attachWith P (fun x h => by simp at H; exact H x (.inl h))).push ⟨a, H a (by simp)⟩ := by
-  cases l
-  simp [attachWith_congr (List.push_toArray _ _)]
-
-theorem pmap_eq_map_attach {p : α → Prop} (f : ∀ a, p a → β) (l H) :
-    pmap f l H = l.attach.map fun x => f x.1 (H _ x.2) := by
-  cases l
-  simp [List.pmap_eq_map_attach]
-
-theorem attach_map_coe (l : Array α) (f : α → β) :
-    (l.attach.map fun (i : {i // i ∈ l}) => f i) = l.map f := by
-  cases l
-  simp [List.attach_map_coe]
-
-theorem attach_map_val (l : Array α) (f : α → β) : (l.attach.map fun i => f i.val) = l.map f :=
-  attach_map_coe _ _
-
-@[simp]
-theorem attach_map_subtype_val (l : Array α) : l.attach.map Subtype.val = l := by
-  cases l; simp
-
-theorem attachWith_map_coe {p : α → Prop} (f : α → β) (l : Array α) (H : ∀ a ∈ l, p a) :
-    ((l.attachWith p H).map fun (i : { i // p i}) => f i) = l.map f := by
-  cases l; simp
-
-theorem attachWith_map_val {p : α → Prop} (f : α → β) (l : Array α) (H : ∀ a ∈ l, p a) :
-    ((l.attachWith p H).map fun i => f i.val) = l.map f :=
-  attachWith_map_coe _ _ _
-
-@[simp]
-theorem attachWith_map_subtype_val {p : α → Prop} (l : Array α) (H : ∀ a ∈ l, p a) :
-    (l.attachWith p H).map Subtype.val = l := by
-  cases l; simp
-
-@[simp]
-theorem mem_attach (l : Array α) : ∀ x, x ∈ l.attach
-  | ⟨a, h⟩ => by
-    have := mem_map.1 (by rw [attach_map_subtype_val] <;> exact h)
-    rcases this with ⟨⟨_, _⟩, m, rfl⟩
-    exact m
-
-@[simp]
-theorem mem_pmap {p : α → Prop} {f : ∀ a, p a → β} {l H b} :
-    b ∈ pmap f l H ↔ ∃ (a : _) (h : a ∈ l), f a (H a h) = b := by
-  simp only [pmap_eq_map_attach, mem_map, mem_attach, true_and, Subtype.exists, eq_comm]
-
-theorem mem_pmap_of_mem {p : α → Prop} {f : ∀ a, p a → β} {l H} {a} (h : a ∈ l) :
-    f a (H a h) ∈ pmap f l H := by
-  rw [mem_pmap]
-  exact ⟨a, h, rfl⟩
-
-@[simp]
-theorem size_pmap {p : α → Prop} {f : ∀ a, p a → β} {l H} : (pmap f l H).size = l.size := by
-  cases l; simp
-
-@[simp]
-theorem size_attach {L : Array α} : L.attach.size = L.size := by
-  cases L; simp
-
-@[simp]
-theorem size_attachWith {p : α → Prop} {l : Array α} {H} : (l.attachWith p H).size = l.size := by
-  cases l; simp
-
-@[simp]
-theorem pmap_eq_empty_iff {p : α → Prop} {f : ∀ a, p a → β} {l H} : pmap f l H = #[] ↔ l = #[] := by
-  cases l; simp
-
-theorem pmap_ne_empty_iff {P : α → Prop} (f : (a : α) → P a → β) {xs : Array α}
-    (H : ∀ (a : α), a ∈ xs → P a) : xs.pmap f H ≠ #[] ↔ xs ≠ #[] := by
-  cases xs; simp
-
-theorem pmap_eq_self {l : Array 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
-  cases l; simp [List.pmap_eq_self]
-
-@[simp]
-theorem attach_eq_empty_iff {l : Array α} : l.attach = #[] ↔ l = #[] := by
-  cases l; simp
-
-theorem attach_ne_empty_iff {l : Array α} : l.attach ≠ #[] ↔ l ≠ #[] := by
-  cases l; simp
-
-@[simp]
-theorem attachWith_eq_empty_iff {l : Array α} {P : α → Prop} {H : ∀ a ∈ l, P a} :
-    l.attachWith P H = #[] ↔ l = #[] := by
-  cases l; simp
-
-theorem attachWith_ne_empty_iff {l : Array α} {P : α → Prop} {H : ∀ a ∈ l, P a} :
-    l.attachWith P H ≠ #[] ↔ l ≠ #[] := by
-  cases l; simp
-
-@[simp]
-theorem getElem?_pmap {p : α → Prop} (f : ∀ a, p a → β) {l : Array α} (h : ∀ a ∈ l, p a) (n : Nat) :
-    (pmap f l h)[n]? = Option.pmap f l[n]? fun x H => h x (mem_of_getElem? H) := by
-  cases l; simp
-
-@[simp]
-theorem getElem_pmap {p : α → Prop} (f : ∀ a, p a → β) {l : Array α} (h : ∀ a ∈ l, p a) {n : Nat}
-    (hn : n < (pmap f l h).size) :
-    (pmap f l h)[n] =
-      f (l[n]'(@size_pmap _ _ p f l h ▸ hn))
-        (h _ (getElem_mem (@size_pmap _ _ p f l h ▸ hn))) := by
-  cases l; simp
-
-@[simp]
-theorem getElem?_attachWith {xs : Array α} {i : Nat} {P : α → Prop} {H : ∀ a ∈ xs, P a} :
-    (xs.attachWith P H)[i]? = xs[i]?.pmap Subtype.mk (fun _ a => H _ (mem_of_getElem? a)) :=
-  getElem?_pmap ..
-
-@[simp]
-theorem getElem?_attach {xs : Array α} {i : Nat} :
-    xs.attach[i]? = xs[i]?.pmap Subtype.mk (fun _ a => mem_of_getElem? a) :=
-  getElem?_attachWith
-
-@[simp]
-theorem getElem_attachWith {xs : Array α} {P : α → Prop} {H : ∀ a ∈ xs, P a}
-    {i : Nat} (h : i < (xs.attachWith P H).size) :
-    (xs.attachWith P H)[i] = ⟨xs[i]'(by simpa using h), H _ (getElem_mem (by simpa using h))⟩ :=
-  getElem_pmap _ _ h
-
-@[simp]
-theorem getElem_attach {xs : Array α} {i : Nat} (h : i < xs.attach.size) :
-    xs.attach[i] = ⟨xs[i]'(by simpa using h), getElem_mem (by simpa using h)⟩ :=
-  getElem_attachWith h
-
-theorem foldl_pmap (l : Array α) {P : α → Prop} (f : (a : α) → P a → β)
-  (H : ∀ (a : α), a ∈ l → P a) (g : γ → β → γ) (x : γ) :
-    (l.pmap f H).foldl g x = l.attach.foldl (fun acc a => g acc (f a.1 (H _ a.2))) x := by
-  rw [pmap_eq_map_attach, foldl_map]
-
-theorem foldr_pmap (l : Array α) {P : α → Prop} (f : (a : α) → P a → β)
-  (H : ∀ (a : α), a ∈ l → P a) (g : β → γ → γ) (x : γ) :
-    (l.pmap f H).foldr g x = l.attach.foldr (fun a acc => g (f a.1 (H _ a.2)) acc) x := by
-  rw [pmap_eq_map_attach, foldr_map]
-
-/--
-If we fold over `l.attach` with a function that ignores the membership predicate,
-we get the same results as folding over `l` directly.
-
-This is useful when we need to use `attach` to show termination.
-
-Unfortunately this can't be applied by `simp` because of the higher order unification problem,
-and even when rewriting we need to specify the function explicitly.
-See however `foldl_subtype` below.
--/
-theorem foldl_attach (l : Array α) (f : β → α → β) (b : β) :
-    l.attach.foldl (fun acc t => f acc t.1) b = l.foldl f b := by
-  rcases l with ⟨l⟩
-  simp only [List.attach_toArray, List.attachWith_mem_toArray, List.map_attach, size_toArray,
-    List.length_pmap, List.foldl_toArray', mem_toArray, List.foldl_subtype]
-  congr
-  ext
-  simpa using fun a => List.mem_of_getElem? a
-
-/--
-If we fold over `l.attach` with a function that ignores the membership predicate,
-we get the same results as folding over `l` directly.
-
-This is useful when we need to use `attach` to show termination.
-
-Unfortunately this can't be applied by `simp` because of the higher order unification problem,
-and even when rewriting we need to specify the function explicitly.
-See however `foldr_subtype` below.
--/
-theorem foldr_attach (l : Array α) (f : α → β → β) (b : β) :
-    l.attach.foldr (fun t acc => f t.1 acc) b = l.foldr f b := by
-  rcases l with ⟨l⟩
-  simp only [List.attach_toArray, List.attachWith_mem_toArray, List.map_attach, size_toArray,
-    List.length_pmap, List.foldr_toArray', mem_toArray, List.foldr_subtype]
-  congr
-  ext
-  simpa using fun a => List.mem_of_getElem? a
-
-theorem attach_map {l : Array α} (f : α → β) :
-    (l.map f).attach = l.attach.map (fun ⟨x, h⟩ => ⟨f x, mem_map_of_mem f h⟩) := by
-  cases l
-  ext <;> simp
-
-theorem attachWith_map {l : Array α} (f : α → β) {P : β → Prop} {H : ∀ (b : β), b ∈ l.map f → P b} :
-    (l.map f).attachWith P H = (l.attachWith (P ∘ f) (fun _ h => H _ (mem_map_of_mem f h))).map
-      fun ⟨x, h⟩ => ⟨f x, h⟩ := by
-  cases l
-  ext
-  · simp
-  · simp only [List.map_toArray, List.attachWith_toArray, List.getElem_toArray,
-      List.getElem_attachWith, List.getElem_map, Function.comp_apply]
-    erw [List.getElem_attachWith] -- Why is `erw` needed here?
-
-theorem map_attachWith {l : Array α} {P : α → Prop} {H : ∀ (a : α), a ∈ l → P a}
-    (f : { x // P x } → β) :
-    (l.attachWith P H).map f =
-      l.pmap (fun a (h : a ∈ l ∧ P a) => f ⟨a, H _ h.1⟩) (fun a h => ⟨h, H a h⟩) := by
-  cases l
-  ext <;> simp
-
-/-- See also `pmap_eq_map_attach` for writing `pmap` in terms of `map` and `attach`. -/
-theorem map_attach {l : Array α} (f : { x // x ∈ l } → β) :
-    l.attach.map f = l.pmap (fun a h => f ⟨a, h⟩) (fun _ => id) := by
-  cases l
-  ext <;> simp
-
-theorem attach_filterMap {l : Array α} {f : α → Option β} :
-    (l.filterMap f).attach = l.attach.filterMap
-      fun ⟨x, h⟩ => (f x).pbind (fun b m => some ⟨b, mem_filterMap.mpr ⟨x, h, m⟩⟩) := by
-  cases l
-  rw [attach_congr (List.filterMap_toArray f _)]
-  simp [List.attach_filterMap, List.map_filterMap, Function.comp_def]
-
-theorem attach_filter {l : Array α} (p : α → Bool) :
-    (l.filter p).attach = l.attach.filterMap
-      fun x => if w : p x.1 then some ⟨x.1, mem_filter.mpr ⟨x.2, w⟩⟩ else none := by
-  cases l
-  rw [attach_congr (List.filter_toArray p _)]
-  simp [List.attach_filter, List.map_filterMap, Function.comp_def]
-
--- We are still missing here `attachWith_filterMap` and `attachWith_filter`.
--- Also missing are `filterMap_attach`, `filter_attach`, `filterMap_attachWith` and `filter_attachWith`.
-
-theorem pmap_pmap {p : α → Prop} {q : β → Prop} (g : ∀ a, p a → β) (f : ∀ b, q b → γ) (l H₁ H₂) :
-    pmap f (pmap g l H₁) H₂ =
-      pmap (α := { x // x ∈ l }) (fun a h => f (g a h) (H₂ (g a h) (mem_pmap_of_mem a.2))) l.attach
-        (fun a _ => H₁ a a.2) := by
-  cases l
-  simp [List.pmap_pmap, List.pmap_map]
-
-@[simp] theorem pmap_append {p : ι → Prop} (f : ∀ a : ι, p a → α) (l₁ l₂ : Array ι)
-    (h : ∀ a ∈ l₁ ++ l₂, p a) :
-    (l₁ ++ l₂).pmap f h =
-      (l₁.pmap f fun a ha => h a (mem_append_left l₂ ha)) ++
-        l₂.pmap f fun a ha => h a (mem_append_right l₁ ha) := by
-  cases l₁
-  cases l₂
-  simp
-
-theorem pmap_append' {p : α → Prop} (f : ∀ a : α, p a → β) (l₁ l₂ : Array α)
-    (h₁ : ∀ a ∈ l₁, p a) (h₂ : ∀ a ∈ l₂, p a) :
-    ((l₁ ++ l₂).pmap f fun a ha => (mem_append.1 ha).elim (h₁ a) (h₂ a)) =
-      l₁.pmap f h₁ ++ l₂.pmap f h₂ :=
-  pmap_append f l₁ l₂ _
-
-@[simp] theorem attach_append (xs ys : Array α) :
-    (xs ++ ys).attach = xs.attach.map (fun ⟨x, h⟩ => ⟨x, mem_append_left ys h⟩) ++
-      ys.attach.map fun ⟨x, h⟩ => ⟨x, mem_append_right xs h⟩ := by
-  cases xs
-  cases ys
-  rw [attach_congr (List.append_toArray _ _)]
-  simp [List.attach_append, Function.comp_def]
-
-@[simp] theorem attachWith_append {P : α → Prop} {xs ys : Array α}
-    {H : ∀ (a : α), a ∈ xs ++ ys → P a} :
-    (xs ++ ys).attachWith P H = xs.attachWith P (fun a h => H a (mem_append_left ys h)) ++
-      ys.attachWith P (fun a h => H a (mem_append_right xs h)) := by
-  simp [attachWith, attach_append, map_pmap, pmap_append]
-
-@[simp] theorem pmap_reverse {P : α → Prop} (f : (a : α) → P a → β) (xs : Array α)
-    (H : ∀ (a : α), a ∈ xs.reverse → P a) :
-    xs.reverse.pmap f H = (xs.pmap f (fun a h => H a (by simpa using h))).reverse := by
-  induction xs <;> simp_all
-
-theorem reverse_pmap {P : α → Prop} (f : (a : α) → P a → β) (xs : Array α)
-    (H : ∀ (a : α), a ∈ xs → P a) :
-    (xs.pmap f H).reverse = xs.reverse.pmap f (fun a h => H a (by simpa using h)) := by
-  rw [pmap_reverse]
-
-@[simp] theorem attachWith_reverse {P : α → Prop} {xs : Array α}
-    {H : ∀ (a : α), a ∈ xs.reverse → P a} :
-    xs.reverse.attachWith P H =
-      (xs.attachWith P (fun a h => H a (by simpa using h))).reverse := by
-  cases xs
-  simp
-
-theorem reverse_attachWith {P : α → Prop} {xs : Array α}
-    {H : ∀ (a : α), a ∈ xs → P a} :
-    (xs.attachWith P H).reverse = (xs.reverse.attachWith P (fun a h => H a (by simpa using h))) := by
-  cases xs
-  simp
-
-@[simp] theorem attach_reverse (xs : Array α) :
-    xs.reverse.attach = xs.attach.reverse.map fun ⟨x, h⟩ => ⟨x, by simpa using h⟩ := by
-  cases xs
-  rw [attach_congr (List.reverse_toArray _)]
-  simp
-
-theorem reverse_attach (xs : Array α) :
-    xs.attach.reverse = xs.reverse.attach.map fun ⟨x, h⟩ => ⟨x, by simpa using h⟩ := by
-  cases xs
-  simp
-
-@[simp] theorem back?_pmap {P : α → Prop} (f : (a : α) → P a → β) (xs : Array α)
-    (H : ∀ (a : α), a ∈ xs → P a) :
-    (xs.pmap f H).back? = xs.attach.back?.map fun ⟨a, m⟩ => f a (H a m) := by
-  cases xs
-  simp
-
-@[simp] theorem back?_attachWith {P : α → Prop} {xs : Array α}
-    {H : ∀ (a : α), a ∈ xs → P a} :
-    (xs.attachWith P H).back? = xs.back?.pbind (fun a h => some ⟨a, H _ (mem_of_back?_eq_some h)⟩) := by
-  cases xs
-  simp
-
-@[simp]
-theorem back?_attach {xs : Array α} :
-    xs.attach.back? = xs.back?.pbind fun a h => some ⟨a, mem_of_back?_eq_some h⟩ := by
-  cases xs
-  simp
-
 /-! ## unattach
 
 `Array.unattach` is the (one-sided) inverse of `Array.attach`. It is a synonym for `Array.map Subtype.val`.
@@ -487,15 +128,6 @@ def unattach {α : Type _} {p : α → Prop} (l : Array { x // p x }) := l.map (
   cases l
   simp
 
-@[simp] theorem getElem?_unattach {p : α → Prop} {l : Array { x // p x }} (i : Nat) :
-    l.unattach[i]? = l[i]?.map Subtype.val := by
-  simp [unattach]
-
-@[simp] theorem getElem_unattach
-    {p : α → Prop} {l : Array { x // p x }} (i : Nat) (h : i < l.unattach.size) :
-    l.unattach[i] = (l[i]'(by simpa using h)).1 := by
-  simp [unattach]
-
 /-! ### Recognizing higher order functions using a function that only depends on the value. -/
 
 /--

src/Init/Data/Array/Basic.lean

@@ -11,9 +11,8 @@ import Init.Data.UInt.BasicAux
 import Init.Data.Repr
 import Init.Data.ToString.Basic
 import Init.GetElem
-import Init.Data.List.ToArrayImpl
+import Init.Data.List.ToArray
 import Init.Data.Array.Set
-
 universe u v w
 
 /-! ### Array literal syntax -/
@@ -85,8 +84,6 @@ theorem ext' {as bs : Array α} (h : as.toList = bs.toList) : as = bs := by
 
 @[simp] theorem getElem_toList {a : Array α} {i : Nat} (h : i < a.size) : a.toList[i] = a[i] := rfl
 
-@[simp] theorem getElem?_toList {a : Array α} {i : Nat} : a.toList[i]? = a[i]? := rfl
-
 /-- `a ∈ as` is a predicate which asserts that `a` is in the array `as`. -/
 -- NB: This is defined as a structure rather than a plain def so that a lemma
 -- like `sizeOf_lt_of_mem` will not apply with no actual arrays around.
@@ -99,9 +96,6 @@ instance : Membership α (Array α) where
 theorem mem_def {a : α} {as : Array α} : a ∈ as ↔ a ∈ as.toList :=
   ⟨fun | .mk h => h, Array.Mem.mk⟩
 
-@[simp] theorem mem_toArray {a : α} {l : List α} : a ∈ l.toArray ↔ a ∈ l := by
-  simp [mem_def]
-
 @[simp] theorem getElem_mem {l : Array α} {i : Nat} (h : i < l.size) : l[i] ∈ l := by
   rw [Array.mem_def, ← getElem_toList]
   apply List.getElem_mem
@@ -171,15 +165,15 @@ This will perform the update destructively provided that `a` has a reference
 count of 1 when called.
 -/
 @[extern "lean_array_fswap"]
-def swap (a : Array α) (i j : @& Nat) (hi : i < a.size := by get_elem_tactic) (hj : j < a.size := by get_elem_tactic) : Array α :=
+def swap (a : Array α) (i j : @& Fin a.size) : Array α :=
   let v₁ := a[i]
   let v₂ := a[j]
   let a'  := a.set i v₂
-  a'.set j v₁ (Nat.lt_of_lt_of_eq hj (size_set a i v₂ _).symm)
+  a'.set j v₁ (Nat.lt_of_lt_of_eq j.isLt (size_set a i v₂ _).symm)
 
-@[simp] theorem size_swap (a : Array α) (i j : Nat) {hi hj} : (a.swap i j hi hj).size = a.size := by
+@[simp] theorem size_swap (a : Array α) (i j : Fin a.size) : (a.swap i j).size = a.size := by
   show ((a.set i a[j]).set j a[i]
-    (Nat.lt_of_lt_of_eq hj (size_set a i a[j] _).symm)).size = a.size
+    (Nat.lt_of_lt_of_eq j.isLt (size_set a i a[j] _).symm)).size = a.size
   rw [size_set, size_set]
 
 /--
@@ -189,14 +183,12 @@ This will perform the update destructively provided that `a` has a reference
 count of 1 when called.
 -/
 @[extern "lean_array_swap"]
-def swapIfInBounds (a : Array α) (i j : @& Nat) : Array α :=
+def swap! (a : Array α) (i j : @& Nat) : Array α :=
   if h₁ : i < a.size then
-  if h₂ : j < a.size then swap a i j
+  if h₂ : j < a.size then swap a ⟨i, h₁⟩ ⟨j, h₂⟩
   else a
   else a
 
-@[deprecated swapIfInBounds (since := "2024-11-24")] abbrev swap! := @swapIfInBounds
-
 /-! ### GetElem instance for `USize`, backed by `uget` -/
 
 instance : GetElem (Array α) USize α fun xs i => i.toNat < xs.size where
@@ -241,13 +233,13 @@ def ofFn {n} (f : Fin n → α) : Array α := go 0 (mkEmpty n) where
 
 /-- The array `#[0, 1, ..., n - 1]`. -/
 def range (n : Nat) : Array Nat :=
-  ofFn fun (i : Fin n) => i
+  n.fold (flip Array.push) (mkEmpty n)
 
 def singleton (v : α) : Array α :=
   mkArray 1 v
 
 def back! [Inhabited α] (a : Array α) : α :=
-  a[a.size - 1]!
+  a.get! (a.size - 1)
 
 @[deprecated back! (since := "2024-10-31")] abbrev back := @back!
 
@@ -257,7 +249,7 @@ def get? (a : Array α) (i : Nat) : Option α :=
 def back? (a : Array α) : Option α :=
   a[a.size - 1]?
 
-@[inline] def swapAt (a : Array α) (i : Nat) (v : α) (hi : i < a.size := by get_elem_tactic) : α × Array α :=
+@[inline] def swapAt (a : Array α) (i : Fin a.size) (v : α) : α × Array α :=
   let e := a[i]
   let a := a.set i v
   (e, a)
@@ -265,7 +257,7 @@ def back? (a : Array α) : Option α :=
 @[inline]
 def swapAt! (a : Array α) (i : Nat) (v : α) : α × Array α :=
   if h : i < a.size then
-    swapAt a i v
+    swapAt a ⟨i, h⟩ v
   else
     have : Inhabited (α × Array α) := ⟨(v, a)⟩
     panic! ("index " ++ toString i ++ " out of bounds")
@@ -479,10 +471,6 @@ def findSomeM? {α : Type u} {β : Type v} {m : Type v → Type w} [Monad m] (f
     | _      => pure ⟨⟩
   return none
 
-/--
-Note that the universe level is contrained to `Type` here,
-to avoid having to have the predicate live in `p : α → m (ULift Bool)`.
--/
 @[inline]
 def findM? {α : Type} {m : Type → Type} [Monad m] (p : α → m Bool) (as : Array α) : m (Option α) := do
   for a in as do
@@ -594,12 +582,8 @@ def zipWithIndex (arr : Array α) : Array (α × Nat) :=
   arr.mapIdx fun i a => (a, i)
 
 @[inline]
-def find? {α : Type u} (p : α → Bool) (as : Array α) : Option α :=
-  Id.run do
-    for a in as do
-      if p a then
-        return a
-    return none
+def find? {α : Type} (p : α → Bool) (as : Array α) : Option α :=
+  Id.run <| as.findM? p
 
 @[inline]
 def findSome? {α : Type u} {β : Type v} (f : α → Option β) (as : Array α) : Option β :=
@@ -629,15 +613,8 @@ def findIdx? {α : Type u} (p : α → Bool) (as : Array α) : Option Nat :=
     decreasing_by simp_wf; decreasing_trivial_pre_omega
   loop 0
 
-@[inline]
-def findFinIdx? {α : Type u} (p : α → Bool) (as : Array α) : Option (Fin as.size) :=
-  let rec @[semireducible] -- This is otherwise irreducible because it uses well-founded recursion.
-  loop (j : Nat) :=
-    if h : j < as.size then
-      if p as[j] then some ⟨j, h⟩ else loop (j + 1)
-    else none
-    decreasing_by simp_wf; decreasing_trivial_pre_omega
-  loop 0
+def getIdx? [BEq α] (a : Array α) (v : α) : Option Nat :=
+  a.findIdx? fun a => a == v
 
 @[semireducible] -- This is otherwise irreducible because it uses well-founded recursion.
 def indexOfAux [BEq α] (a : Array α) (v : α) (i : Nat) : Option (Fin a.size) :=
@@ -650,10 +627,6 @@ decreasing_by simp_wf; decreasing_trivial_pre_omega
 def indexOf? [BEq α] (a : Array α) (v : α) : Option (Fin a.size) :=
   indexOfAux a v 0
 
-@[deprecated indexOf? (since := "2024-11-20")]
-def getIdx? [BEq α] (a : Array α) (v : α) : Option Nat :=
-  a.findIdx? fun a => a == v
-
 @[inline]
 def any (as : Array α) (p : α → Bool) (start := 0) (stop := as.size) : Bool :=
   Id.run <| as.anyM p start stop
@@ -663,7 +636,7 @@ def all (as : Array α) (p : α → Bool) (start := 0) (stop := as.size) : Bool
   Id.run <| as.allM p start stop
 
 def contains [BEq α] (as : Array α) (a : α) : Bool :=
-  as.any (a == ·)
+  as.any (· == a)
 
 def elem [BEq α] (a : α) (as : Array α) : Bool :=
   as.contains a
@@ -762,7 +735,7 @@ where
   loop (as : Array α) (i : Nat) (j : Fin as.size) :=
     if h : i < j then
       have := termination h
-      let as := as.swap i j (Nat.lt_trans h j.2)
+      let as := as.swap ⟨i, Nat.lt_trans h j.2⟩ j
       have : j-1 < as.size := by rw [size_swap]; exact Nat.lt_of_le_of_lt (Nat.pred_le _) j.2
       loop as (i+1) ⟨j-1, this⟩
     else
@@ -793,63 +766,49 @@ def takeWhile (p : α → Bool) (as : Array α) : Array α :=
     decreasing_by simp_wf; decreasing_trivial_pre_omega
   go 0 #[]
 
-/--
-Remove the element at a given index from an array without a runtime bounds checks,
-using a `Nat` index and a tactic-provided bound.
+/-- Remove the element at a given index from an array without bounds checks, using a `Fin` index.
 
-This function takes worst case O(n) time because
-it has to backshift all elements at positions greater than `i`.-/
+  This function takes worst case O(n) time because
+  it has to backshift all elements at positions greater than `i`.-/
 @[semireducible] -- This is otherwise irreducible because it uses well-founded recursion.
-def eraseIdx (a : Array α) (i : Nat) (h : i < a.size := by get_elem_tactic) : Array α :=
-  if h' : i + 1 < a.size then
-    let a' := a.swap (i + 1) i
-    a'.eraseIdx (i + 1) (by simp [a', h'])
+def feraseIdx (a : Array α) (i : Fin a.size) : Array α :=
+  if h : i.val + 1 < a.size then
+    let a' := a.swap ⟨i.val + 1, h⟩ i
+    let i' : Fin a'.size := ⟨i.val + 1, by simp [a', h]⟩
+    a'.feraseIdx i'
   else
     a.pop
-termination_by a.size - i
-decreasing_by simp_wf; exact Nat.sub_succ_lt_self _ _ h
+termination_by a.size - i.val
+decreasing_by simp_wf; exact Nat.sub_succ_lt_self _ _ i.isLt
 
 -- This is required in `Lean.Data.PersistentHashMap`.
-@[simp] theorem size_eraseIdx (a : Array α) (i : Nat) (h) : (a.eraseIdx i h).size = a.size - 1 := by
-  induction a, i, h using Array.eraseIdx.induct with
-  | @case1 a i h h' a' ih =>
-    unfold eraseIdx
-    simp [h', a', ih]
-  | case2 a i h h' =>
-    unfold eraseIdx
-    simp [h']
+@[simp] theorem size_feraseIdx (a : Array α) (i : Fin a.size) : (a.feraseIdx i).size = a.size - 1 := by
+  induction a, i using Array.feraseIdx.induct with
+  | @case1 a i h a' _ ih =>
+    unfold feraseIdx
+    simp [h, a', ih]
+  | case2 a i h =>
+    unfold feraseIdx
+    simp [h]
 
 /-- Remove the element at a given index from an array, or do nothing if the index is out of bounds.
 
   This function takes worst case O(n) time because
   it has to backshift all elements at positions greater than `i`.-/
-def eraseIdxIfInBounds (a : Array α) (i : Nat) : Array α :=
-  if h : i < a.size then a.eraseIdx i h else a
-
-/-- Remove the element at a given index from an array, or panic if the index is out of bounds.
-
-This function takes worst case O(n) time because
-it has to backshift all elements at positions greater than `i`. -/
-def eraseIdx! (a : Array α) (i : Nat) : Array α :=
-  if h : i < a.size then a.eraseIdx i h else panic! "invalid index"
+def eraseIdx (a : Array α) (i : Nat) : Array α :=
+  if h : i < a.size then a.feraseIdx ⟨i, h⟩ else a
 
 def erase [BEq α] (as : Array α) (a : α) : Array α :=
   match as.indexOf? a with
   | none   => as
-  | some i => as.eraseIdx i
-
-/-- Erase the first element that satisfies the predicate `p`. -/
-def eraseP (as : Array α) (p : α → Bool) : Array α :=
-  match as.findIdx? p with
-  | none   => as
-  | some i => as.eraseIdxIfInBounds i
+  | some i => as.feraseIdx i
 
 /-- Insert element `a` at position `i`. -/
-@[inline] def insertIdx (as : Array α) (i : Nat) (a : α) (_ : i ≤ as.size := by get_elem_tactic) : Array α :=
+@[inline] def insertAt (as : Array α) (i : Fin (as.size + 1)) (a : α) : Array α :=
   let rec @[semireducible] -- This is otherwise irreducible because it uses well-founded recursion.
   loop (as : Array α) (j : Fin as.size) :=
-    if i < j then
-      let j' : Fin as.size := ⟨j-1, Nat.lt_of_le_of_lt (Nat.pred_le _) j.2⟩
+    if i.1 < j then
+      let j' := ⟨j-1, Nat.lt_of_le_of_lt (Nat.pred_le _) j.2⟩
       let as := as.swap j' j
       loop as ⟨j', by rw [size_swap]; exact j'.2⟩
     else
@@ -859,23 +818,12 @@ def eraseP (as : Array α) (p : α → Bool) : Array α :=
   let as := as.push a
   loop as ⟨j, size_push .. ▸ j.lt_succ_self⟩
 
-@[deprecated insertIdx (since := "2024-11-20")] abbrev insertAt := @insertIdx
-
 /-- Insert element `a` at position `i`. Panics if `i` is not `i ≤ as.size`. -/
-def insertIdx! (as : Array α) (i : Nat) (a : α) : Array α :=
+def insertAt! (as : Array α) (i : Nat) (a : α) : Array α :=
   if h : i ≤ as.size then
-    insertIdx as i a
+    insertAt as ⟨i, Nat.lt_succ_of_le h⟩ a
   else panic! "invalid index"
 
-@[deprecated insertIdx! (since := "2024-11-20")] abbrev insertAt! := @insertIdx!
-
-/-- Insert element `a` at position `i`, or do nothing if `as.size < i`. -/
-def insertIdxIfInBounds (as : Array α) (i : Nat) (a : α) : Array α :=
-  if h : i ≤ as.size then
-    insertIdx as i a
-  else
-    as
-
 @[semireducible] -- This is otherwise irreducible because it uses well-founded recursion.
 def isPrefixOfAux [BEq α] (as bs : Array α) (hle : as.size ≤ bs.size) (i : Nat) : Bool :=
   if h : i < as.size then
@@ -899,12 +847,12 @@ def isPrefixOf [BEq α] (as bs : Array α) : Bool :=
     false
 
 @[semireducible, specialize] -- This is otherwise irreducible because it uses well-founded recursion.
-def zipWithAux (as : Array α) (bs : Array β) (f : α → β → γ) (i : Nat) (cs : Array γ) : Array γ :=
+def zipWithAux (f : α → β → γ) (as : Array α) (bs : Array β) (i : Nat) (cs : Array γ) : Array γ :=
   if h : i < as.size then
     let a := as[i]
     if h : i < bs.size then
       let b := bs[i]
-      zipWithAux as bs f (i+1) <| cs.push <| f a b
+      zipWithAux f as bs (i+1) <| cs.push <| f a b
     else
       cs
   else
@@ -912,23 +860,11 @@ def zipWithAux (as : Array α) (bs : Array β) (f : α → β → γ) (i : Nat)
 decreasing_by simp_wf; decreasing_trivial_pre_omega
 
 @[inline] def zipWith (as : Array α) (bs : Array β) (f : α → β → γ) : Array γ :=
-  zipWithAux as bs f 0 #[]
+  zipWithAux f as bs 0 #[]
 
 def zip (as : Array α) (bs : Array β) : Array (α × β) :=
   zipWith as bs Prod.mk
 
-def zipWithAll (as : Array α) (bs : Array β) (f : Option α → Option β → γ) : Array γ :=
-  go as bs 0 #[]
-where go (as : Array α) (bs : Array β) (i : Nat) (cs : Array γ) :=
-  if i < max as.size bs.size then
-    let a := as[i]?
-    let b := bs[i]?
-    go as bs (i+1) (cs.push (f a b))
-  else
-    cs
-  termination_by max as.size bs.size - i
-  decreasing_by simp_wf; decreasing_trivial_pre_omega
-
 def unzip (as : Array (α × β)) : Array α × Array β :=
   as.foldl (init := (#[], #[])) fun (as, bs) (a, b) => (as.push a, bs.push b)
 

src/Init/Data/Array/BinSearch.lean

@@ -5,64 +5,59 @@ Authors: Leonardo de Moura
 -/
 prelude
 import Init.Data.Array.Basic
-import Init.Omega
 universe u v
 
-namespace Array
+-- TODO: CLEANUP
 
-@[specialize] def binSearchAux {α : Type u} {β : Type v} (lt : α → α → Bool) (found : Option α → β) (as : Array α) (k : α) :
-    (lo : Fin (as.size + 1)) → (hi : Fin as.size) → (lo.1 ≤ hi.1) → β
-  | lo, hi, h =>
-    let m := (lo.1 + hi.1)/2
-    let a := as[m]
-    if lt a k then
-      if h' : m + 1 ≤ hi.1 then
-        binSearchAux lt found as k ⟨m+1, by omega⟩ hi h'
-      else found none
-    else if lt k a then
-      if h' : m = 0 ∨ m - 1 < lo.1 then found none
-      else binSearchAux lt found as k lo ⟨m-1, by omega⟩ (by simp; omega)
-    else found (some a)
-termination_by lo hi => hi.1 - lo.1
+namespace Array
+-- TODO: remove the [Inhabited α] parameters as soon as we have the tactic framework for automating proof generation and using Array.fget
+-- TODO: remove `partial` using well-founded recursion
+
+@[specialize] partial def binSearchAux {α : Type u} {β : Type v} [Inhabited β] (lt : α → α → Bool) (found : Option α → β) (as : Array α) (k : α) : Nat → Nat → β
+  | lo, hi =>
+    if lo <= hi then
+      let _ := Inhabited.mk k
+      let m := (lo + hi)/2
+      let a := as.get! m
+      if lt a k then binSearchAux lt found as k (m+1) hi
+      else if lt k a then
+        if m == 0 then found none
+        else binSearchAux lt found as k lo (m-1)
+      else found (some a)
+    else found none
 
 @[inline] def binSearch {α : Type} (as : Array α) (k : α) (lt : α → α → Bool) (lo := 0) (hi := as.size - 1) : Option α :=
-  if h : lo < as.size then
+  if lo < as.size then
     let hi := if hi < as.size then hi else as.size - 1
-    if w : lo ≤ hi then
-      binSearchAux lt id as k ⟨lo, by omega⟩ ⟨hi, by simp [hi]; split <;> omega⟩ (by simp [hi]; omega)
-    else
-      none
+    binSearchAux lt id as k lo hi
   else
     none
 
 @[inline] def binSearchContains {α : Type} (as : Array α) (k : α) (lt : α → α → Bool) (lo := 0) (hi := as.size - 1) : Bool :=
-  if h : lo < as.size then
+  if lo < as.size then
     let hi := if hi < as.size then hi else as.size - 1
-    if w : lo ≤ hi then
-      binSearchAux lt Option.isSome as k ⟨lo, by omega⟩ ⟨hi, by simp [hi]; split <;> omega⟩ (by simp [hi]; omega)
-    else
-      false
+    binSearchAux lt Option.isSome as k lo hi
   else
     false
 
-@[specialize] private def binInsertAux {α : Type u} {m : Type u → Type v} [Monad m]
+@[specialize] private partial def binInsertAux {α : Type u} {m : Type u → Type v} [Monad m]
     (lt : α → α → Bool)
     (merge : α → m α)
     (add : Unit → m α)
     (as : Array α)
-    (k : α) : (lo : Fin as.size) → (hi : Fin as.size) → (lo.1 ≤ hi.1) → (lt as[lo] k) → m (Array α)
-  | lo, hi, h, w =>
-    let mid    := (lo.1 + hi.1)/2
-    let midVal := as[mid]
-    if w₁ : lt midVal k then
-      if h' : mid = lo then do let v ← add (); pure <| as.insertIdx (lo+1) v
-      else binInsertAux lt merge add as k ⟨mid, by omega⟩ hi (by simp; omega) w₁
-    else if w₂ : lt k midVal then
-      have : mid ≠ lo := fun z => by simp [midVal, z] at w₁; simp_all
-      binInsertAux lt merge add as k lo ⟨mid, by omega⟩ (by simp; omega) w
+    (k : α) : Nat → Nat → m (Array α)
+  | lo, hi =>
+    let _ := Inhabited.mk k
+    -- as[lo] < k < as[hi]
+    let mid    := (lo + hi)/2
+    let midVal := as.get! mid
+    if lt midVal k then
+      if mid == lo then do let v ← add (); pure <| as.insertAt! (lo+1) v
+      else binInsertAux lt merge add as k mid hi
+    else if lt k midVal then
+      binInsertAux lt merge add as k lo mid
     else do
       as.modifyM mid <| fun v => merge v
-termination_by lo hi => hi.1 - lo.1
 
 @[specialize] def binInsertM {α : Type u} {m : Type u → Type v} [Monad m]
     (lt : α → α → Bool)
@@ -70,12 +65,13 @@ termination_by lo hi => hi.1 - lo.1
     (add : Unit → m α)
     (as : Array α)
     (k : α) : m (Array α) :=
-  if h : as.size = 0 then do let v ← add (); pure <| as.push v
-  else if lt k as[0] then do let v ← add (); pure <| as.insertIdx 0 v
-  else if h' : !lt as[0] k then as.modifyM 0 <| merge
-  else if lt as[as.size - 1] k then do let v ← add (); pure <| as.push v
-  else if !lt k as[as.size - 1] then as.modifyM (as.size - 1) <| merge
-  else binInsertAux lt merge add as k ⟨0, by omega⟩ ⟨as.size - 1, by omega⟩ (by simp) (by simpa using h')
+  let _ := Inhabited.mk k
+  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 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 :=
   Id.run <| binInsertM lt (fun _ => k) (fun _ => k) as k

src/Init/Data/Array/Bootstrap.lean

@@ -23,7 +23,7 @@ theorem 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_toList.aux f arr i (j+1) H]
-    rw (occs := [2]) [← List.getElem_cons_drop_succ_eq_drop ‹_›]
+    rw (occs := .pos [2]) [← List.getElem_cons_drop_succ_eq_drop ‹_›]
     rfl
   · rw [List.drop_of_length_le (Nat.ge_of_not_lt ‹_›)]; rfl
 

src/Init/Data/Array/DecidableEq.lean

@@ -6,6 +6,7 @@ Authors: Leonardo de Moura
 prelude
 import Init.Data.Array.Basic
 import Init.Data.BEq
+import Init.Data.Nat.Lemmas
 import Init.Data.List.Nat.BEq
 import Init.ByCases
 

src/Init/Data/Array/FinRange.lean

@@ -1,14 +0,0 @@
-/-
-Copyright (c) 2024 François G. Dorais. All rights reserved.
-Released under Apache 2.0 license as described in the file LICENSE.
-Authors: François G. Dorais
--/
-prelude
-import Init.Data.List.FinRange
-
-namespace Array
-
-/-- `finRange n` is the array of all elements of `Fin n` in order. -/
-protected def finRange (n : Nat) : Array (Fin n) := ofFn fun i => i
-
-end Array

src/Init/Data/Array/Find.lean

@@ -81,7 +81,7 @@ theorem getElem_zero_flatten.proof {L : Array (Array α)} (h : 0 < L.flatten.siz
     (L.findSome? fun l => l[0]?).isSome := by
   cases L using array_array_induction
   simp only [List.findSome?_toArray, List.findSome?_map, Function.comp_def, List.getElem?_toArray,
-    List.findSome?_isSome_iff, isSome_getElem?]
+    List.findSome?_isSome_iff, List.isSome_getElem?]
   simp only [flatten_toArray_map_toArray, size_toArray, List.length_flatten,
     Nat.sum_pos_iff_exists_pos, List.mem_map] at h
   obtain ⟨_, ⟨xs, m, rfl⟩, h⟩ := h
@@ -272,10 +272,4 @@ theorem find?_mkArray_eq_none {n : Nat} {a : α} {p : α → Bool} :
     ((mkArray n a).find? p).get h = a := by
   simp [mkArray_eq_toArray_replicate]
 
-theorem find?_pmap {P : α → Prop} (f : (a : α) → P a → β) (xs : Array α)
-    (H : ∀ (a : α), a ∈ xs → P a) (p : β → Bool) :
-    (xs.pmap f H).find? p = (xs.attach.find? (fun ⟨a, m⟩ => p (f a (H a m)))).map fun ⟨a, m⟩ => f a (H a m) := by
-  simp only [pmap_eq_map_attach, find?_map]
-  rfl
-
 end Array

src/Init/Data/Array/InsertionSort.lean

@@ -6,7 +6,7 @@ Authors: Leonardo de Moura
 prelude
 import Init.Data.Array.Basic
 
-@[inline] def Array.insertionSort (a : Array α) (lt : α → α → Bool := by exact (· < ·)) : Array α :=
+@[inline] def Array.insertionSort (a : Array α) (lt : α → α → Bool) : Array α :=
   traverse a 0 a.size
 where
   @[specialize] traverse (a : Array α) (i : Nat) (fuel : Nat) : Array α :=
@@ -23,6 +23,6 @@ where
     | j'+1 =>
       have h' : j' < a.size := by subst j; exact Nat.lt_trans (Nat.lt_succ_self _) h
       if lt a[j] a[j'] then
-        swapLoop (a.swap j j') j' (by rw [size_swap]; assumption; done)
+        swapLoop (a.swap ⟨j, h⟩ ⟨j', h'⟩) j' (by rw [size_swap]; assumption; done)
       else
         a

src/Init/Data/Array/Perm.lean

@@ -1,65 +0,0 @@
-/-
-Copyright (c) 2024 Lean FRO. All rights reserved.
-Released under Apache 2.0 license as described in the file LICENSE.
-Authors: Kim Morrison
--/
-prelude
-import Init.Data.List.Nat.Perm
-import Init.Data.Array.Lemmas
-
-namespace Array
-
-open List
-
-/--
-`Perm as bs` asserts that `as` and `bs` are permutations of each other.
-
-This is a wrapper around `List.Perm`, and for now has much less API.
-For more complicated verification, use `perm_iff_toList_perm` and the `List` API.
--/
-def Perm (as bs : Array α) : Prop :=
-  as.toList ~ bs.toList
-
-@[inherit_doc] scoped infixl:50 " ~ " => Perm
-
-theorem perm_iff_toList_perm {as bs : Array α} : as ~ bs ↔ as.toList ~ bs.toList := Iff.rfl
-
-@[simp] theorem perm_toArray (as bs : List α) : as.toArray ~ bs.toArray ↔ as ~ bs := by
-  simp [perm_iff_toList_perm]
-
-@[simp, refl] protected theorem Perm.refl (l : Array α) : l ~ l := by
-  cases l
-  simp
-
-protected theorem Perm.rfl {l : List α} : l ~ l := .refl _
-
-theorem Perm.of_eq {l₁ l₂ : Array α} (h : l₁ = l₂) : l₁ ~ l₂ := h ▸ .rfl
-
-protected theorem Perm.symm {l₁ l₂ : Array α} (h : l₁ ~ l₂) : l₂ ~ l₁ := by
-  cases l₁; cases l₂
-  simp only [perm_toArray] at h
-  simpa using h.symm
-
-protected theorem Perm.trans {l₁ l₂ l₃ : Array α} (h₁ : l₁ ~ l₂) (h₂ : l₂ ~ l₃) : l₁ ~ l₃ := by
-  cases l₁; cases l₂; cases l₃
-  simp only [perm_toArray] at h₁ h₂
-  simpa using h₁.trans h₂
-
-instance : Trans (Perm (α := α)) (Perm (α := α)) (Perm (α := α)) where
-  trans h₁ h₂ := Perm.trans h₁ h₂
-
-theorem perm_comm {l₁ l₂ : Array α} : l₁ ~ l₂ ↔ l₂ ~ l₁ := ⟨Perm.symm, Perm.symm⟩
-
-theorem Perm.push (x y : α) {l₁ l₂ : Array α} (p : l₁ ~ l₂) :
-    (l₁.push x).push y ~ (l₂.push y).push x := by
-  cases l₁; cases l₂
-  simp only [perm_toArray] at p
-  simp only [push_toArray, List.append_assoc, singleton_append, perm_toArray]
-  exact p.append (Perm.swap' _ _ Perm.nil)
-
-theorem swap_perm {as : Array α} {i j : Nat} (h₁ : i < as.size) (h₂ : j < as.size) :
-    as.swap i j ~ as := by
-  simp only [swap, perm_iff_toList_perm, toList_set]
-  apply set_set_perm
-
-end Array

src/Init/Data/Array/QSort.lean

@@ -4,46 +4,46 @@ Released under Apache 2.0 license as described in the file LICENSE.
 Authors: Leonardo de Moura
 -/
 prelude
-import Init.Data.Vector.Basic
+import Init.Data.Array.Basic
 import Init.Data.Ord
 
 namespace Array
+-- TODO: remove the [Inhabited α] parameters as soon as we have the tactic framework for automating proof generation and using Array.fget
 
-private def qpartition {n} (as : Vector α n) (lt : α → α → Bool) (lo hi : Nat)
-    (hlo : lo < n := by omega) (hhi : hi < n := by omega) : {n : Nat // lo ≤ n} × Vector α n :=
+def qpartition (as : Array α) (lt : α → α → Bool) (lo hi : Nat) : Nat × Array α :=
+  if h : as.size = 0 then (0, as) else have : Inhabited α := ⟨as[0]'(by revert h; cases as.size <;> simp)⟩ -- TODO: remove
   let mid := (lo + hi) / 2
-  let as  := if lt as[mid] as[lo] then as.swap lo mid else as
-  let as  := if lt as[hi]  as[lo] then as.swap lo hi  else as
-  let as  := if lt as[mid] as[hi] then as.swap mid hi else as
-  let pivot := as[hi]
-  let rec loop (as : Vector α n) (i j : Nat)
-      (ilo : lo ≤ i := by omega) (jh : j < n := by omega) (w : i ≤ j := by omega) :=
+  let as  := if lt (as.get! mid) (as.get! lo) then as.swap! lo mid else as
+  let as  := if lt (as.get! hi)  (as.get! lo) then as.swap! lo hi  else as
+  let as  := if lt (as.get! mid) (as.get! hi) then as.swap! mid hi else as
+  let pivot := as.get! hi
+  let rec loop (as : Array α) (i j : Nat) :=
     if h : j < hi then
-      if lt as[j] pivot then
-        loop (as.swap i j) (i+1) (j+1)
+      if lt (as.get! j) pivot then
+        let as := as.swap! i j
+        loop as (i+1) (j+1)
       else
         loop as i (j+1)
     else
-      (⟨i, ilo⟩, as.swap i hi)
+      let as := as.swap! i hi
+      (i, as)
+    termination_by hi - j
+    decreasing_by all_goals simp_wf; decreasing_trivial_pre_omega
   loop as lo lo
 
-@[inline] def qsort (as : Array α) (lt : α → α → Bool := by exact (· < ·))
-    (low := 0) (high := as.size - 1) : Array α :=
-  let rec @[specialize] sort {n} (as : Vector α n) (lo hi : Nat)
-      (hlo : lo < n := by omega) (hhi : hi < n := by omega) :=
-    if h₁ : lo < hi then
-      let ⟨⟨mid, hmid⟩, as⟩ := qpartition as lt lo hi
-      if h₂ : mid ≥ hi then
-        as
+@[inline] partial def qsort (as : Array α) (lt : α → α → Bool) (low := 0) (high := as.size - 1) : Array α :=
+  let rec @[specialize] sort (as : Array α) (low high : Nat) :=
+    if low < high then
+      let p := qpartition as lt low high;
+      -- TODO: fix `partial` support in the equation compiler, it breaks if we use `let (mid, as) := partition as lt low high`
+      let mid := p.1
+      let as  := p.2
+      if mid >= high then as
       else
-        sort (sort as lo mid) (mid+1) hi
+        let as := sort as low mid
+        sort as (mid+1) high
     else as
-  if h : as.size = 0 then
-    as
-  else
-    let low := min low (as.size - 1)
-    let high := min high (as.size - 1)
-    sort ⟨as, rfl⟩ low high |>.toArray
+  sort as low high
 
 set_option linter.unusedVariables.funArgs false in
 /--

src/Init/Data/Array/Set.lean

@@ -25,11 +25,9 @@ Set an element in an array, or do nothing if the index is out of bounds.
 This will perform the update destructively provided that `a` has a reference
 count of 1 when called.
 -/
-@[inline] def Array.setIfInBounds (a : Array α) (i : Nat) (v : α) : Array α :=
+@[inline] def Array.setD (a : Array α) (i : Nat) (v : α) : Array α :=
   dite (LT.lt i a.size) (fun h => a.set i v h) (fun _ => a)
 
-@[deprecated Array.setIfInBounds (since := "2024-11-24")] abbrev Array.setD := @Array.setIfInBounds
-
 /--
 Set an element in an array, or panic if the index is out of bounds.
 
@@ -38,4 +36,4 @@ count of 1 when called.
 -/
 @[extern "lean_array_set"]
 def Array.set! (a : Array α) (i : @& Nat) (v : α) : Array α :=
-  Array.setIfInBounds a i v
+  Array.setD a i v

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

@@ -23,13 +23,16 @@ def split (s : Subarray α) (i : Fin s.size.succ) : (Subarray α × Subarray α)
   let ⟨i', isLt⟩ := i
   have := s.start_le_stop
   have := s.stop_le_array_size
+  have : i' ≤ s.stop - s.start := Nat.lt_succ.mp isLt
+  have : s.start + i' ≤ s.stop := by omega
+  have : s.start + i' ≤ s.array.size := by omega
   have : s.start + i' ≤ s.stop := by
     simp only [size] at isLt
     omega
   let pre := {s with
     stop := s.start + i',
     start_le_stop := by omega,
-    stop_le_array_size := by omega
+    stop_le_array_size := by assumption
   }
   let post := {s with
     start := s.start + i'
@@ -45,7 +48,9 @@ def drop (arr : Subarray α) (i : Nat) : Subarray α where
   array := arr.array
   start := min (arr.start + i) arr.stop
   stop := arr.stop
-  start_le_stop := by omega
+  start_le_stop := by
+    rw [Nat.min_def]
+    split <;> simp only [Nat.le_refl, *]
   stop_le_array_size := arr.stop_le_array_size
 
 /--
@@ -58,7 +63,9 @@ def take (arr : Subarray α) (i : Nat) : Subarray α where
   stop := min (arr.start + i) arr.stop
   start_le_stop := by
     have := arr.start_le_stop
-    omega
+    rw [Nat.min_def]
+    split <;> omega
   stop_le_array_size := by
     have := arr.stop_le_array_size
-    omega
+    rw [Nat.min_def]
+    split <;> omega

src/Init/Data/Array/TakeDrop.lean

@@ -12,7 +12,7 @@ namespace Array
 theorem exists_of_uset (self : Array α) (i d h) :
     ∃ l₁ l₂, self.toList = l₁ ++ self[i] :: l₂ ∧ List.length l₁ = i.toNat ∧
       (self.uset i d h).toList = l₁ ++ d :: l₂ := by
-  simpa only [ugetElem_eq_getElem, ← getElem_toList, uset, toList_set] using
+  simpa only [ugetElem_eq_getElem, getElem_eq_getElem_toList, uset, toList_set] using
     List.exists_of_set _
 
 end Array

src/Init/Data/BEq.lean

@@ -40,9 +40,6 @@ theorem BEq.symm [BEq α] [PartialEquivBEq α] {a b : α} : a == b → b == a :=
 theorem BEq.comm [BEq α] [PartialEquivBEq α] {a b : α} : (a == b) = (b == a) :=
   Bool.eq_iff_iff.2 ⟨BEq.symm, BEq.symm⟩
 
-theorem bne_comm [BEq α] [PartialEquivBEq α] {a b : α} : (a != b) = (b != a) := by
-  rw [bne, BEq.comm, bne]
-
 theorem BEq.symm_false [BEq α] [PartialEquivBEq α] {a b : α} : (a == b) = false → (b == a) = false :=
   BEq.comm (α := α) ▸ id
 

src/Init/Data/BitVec/Basic.lean

@@ -351,17 +351,17 @@ end relations
 section cast
 
 /-- `cast eq x` embeds `x` into an equal `BitVec` type. -/
-@[inline] protected def cast (eq : n = m) (x : BitVec n) : BitVec m := .ofNatLt x.toNat (eq ▸ x.isLt)
+@[inline] def cast (eq : n = m) (x : BitVec n) : BitVec m := .ofNatLt x.toNat (eq ▸ x.isLt)
 
 @[simp] theorem cast_ofNat {n m : Nat} (h : n = m) (x : Nat) :
-    (BitVec.ofNat n x).cast h = BitVec.ofNat m x := by
+    cast h (BitVec.ofNat n x) = BitVec.ofNat m x := by
   subst h; rfl
 
 @[simp] theorem cast_cast {n m k : Nat} (h₁ : n = m) (h₂ : m = k) (x : BitVec n) :
-    (x.cast h₁).cast h₂ = x.cast (h₁ ▸ h₂) :=
+    cast h₂ (cast h₁ x) = cast (h₁ ▸ h₂) x :=
   rfl
 
-@[simp] theorem cast_eq {n : Nat} (h : n = n) (x : BitVec n) : x.cast h = x := rfl
+@[simp] theorem cast_eq {n : Nat} (h : n = n) (x : BitVec n) : cast h x = x := rfl
 
 /--
 Extraction of bits `start` to `start + len - 1` from a bit vector of size `n` to yield a

src/Init/Data/BitVec/Bitblast.lean

@@ -346,10 +346,6 @@ theorem getMsbD_sub {i : Nat} {i_lt : i < w} {x y : BitVec w} :
   · rfl
   · omega
 
-theorem getElem_sub {i : Nat} {x y : BitVec w} (h : i < w) :
-    (x - y)[i] = (x[i] ^^ ((~~~y + 1#w)[i] ^^ carry i x (~~~y + 1#w) false)) := by
-  simp [← getLsbD_eq_getElem, getLsbD_sub, h]
-
 theorem msb_sub {x y: BitVec w} :
     (x - y).msb
       = (x.msb ^^ ((~~~y + 1#w).msb ^^ carry (w - 1 - 0) x (~~~y + 1#w) false)) := by
@@ -414,10 +410,6 @@ theorem getLsbD_neg {i : Nat} {x : BitVec w} :
   · have h_ge : w ≤ i := by omega
     simp [getLsbD_ge _ _ h_ge, h_ge, hi]
 
-theorem getElem_neg {i : Nat} {x : BitVec w} (h : i < w) :
-    (-x)[i] = (x[i] ^^ decide (∃ j < i, x.getLsbD j = true)) := by
-  simp [← getLsbD_eq_getElem, getLsbD_neg, h]
-
 theorem getMsbD_neg {i : Nat} {x : BitVec w} :
     getMsbD (-x) i =
       (getMsbD x i ^^ decide (∃ j < w, i < j ∧ getMsbD x j = true)) := by
@@ -462,7 +454,7 @@ theorem msb_neg {w : Nat} {x : BitVec w} :
       case true =>
         apply hmin
         apply eq_of_getMsbD_eq
-        intro i hi
+        rintro ⟨i, hi⟩
         simp only [getMsbD_intMin, w_pos, decide_true, Bool.true_and]
         cases i
         case zero => exact hmsb
@@ -470,7 +462,7 @@ theorem msb_neg {w : Nat} {x : BitVec w} :
       case false =>
         apply hzero
         apply eq_of_getMsbD_eq
-        intro i hi
+        rintro ⟨i, hi⟩
         simp only [getMsbD_zero]
         cases i
         case zero => exact hmsb
@@ -573,11 +565,11 @@ theorem setWidth_setWidth_succ_eq_setWidth_setWidth_add_twoPow (x : BitVec w) (i
     setWidth w (x.setWidth (i + 1)) =
       setWidth w (x.setWidth i) + (x &&& twoPow w i) := by
   rw [add_eq_or_of_and_eq_zero]
-  · ext k h
-    simp only [getLsbD_setWidth, h, decide_true, Bool.true_and, getLsbD_or, getLsbD_and]
+  · ext k
+    simp only [getLsbD_setWidth, Fin.is_lt, decide_true, Bool.true_and, getLsbD_or, getLsbD_and]
     by_cases hik : i = k
     · subst hik
-      simp [h]
+      simp
     · simp only [getLsbD_twoPow, hik, decide_false, Bool.and_false, Bool.or_false]
       by_cases hik' : k < (i + 1)
       · have hik'' : k < i := by omega

src/Init/Data/Bool.lean

@@ -384,15 +384,6 @@ theorem toNat_lt (b : Bool) : b.toNat < 2 :=
 @[simp] theorem toNat_eq_one  {b : Bool} : b.toNat = 1 ↔ b = true := by
   cases b <;> simp
 
-/-! ## toInt -/
-
-/-- convert a `Bool` to an `Int`, `false -> 0`, `true -> 1` -/
-def toInt (b : Bool) : Int := cond b 1 0
-
-@[simp] theorem toInt_false : false.toInt = 0 := rfl
-
-@[simp] theorem toInt_true : true.toInt = 1 := rfl
-
 /-! ### ite -/
 
 @[simp] theorem if_true_left  (p : Prop) [h : Decidable p] (f : Bool) :

src/Init/Data/ByteArray/Basic.lean

@@ -108,18 +108,8 @@ def toList (bs : ByteArray) : List UInt8 :=
 
 @[inline] def findIdx? (a : ByteArray) (p : UInt8 → Bool) (start := 0) : Option Nat :=
   let rec @[specialize] loop (i : Nat) :=
-    if h : i < a.size then
-      if p a[i] then some i else loop (i+1)
-    else
-      none
-    termination_by a.size - i
-    decreasing_by decreasing_trivial_pre_omega
-  loop start
-
-@[inline] def findFinIdx? (a : ByteArray) (p : UInt8 → Bool) (start := 0) : Option (Fin a.size) :=
-  let rec @[specialize] loop (i : Nat) :=
-    if h : i < a.size then
-      if p a[i] then some ⟨i, h⟩ else loop (i+1)
+    if i < a.size then
+      if p (a.get! i) then some i else loop (i+1)
     else
       none
     termination_by a.size - i

src/Init/Data/Channel.lean

@@ -8,8 +8,6 @@ import Init.Data.Queue
 import Init.System.Promise
 import Init.System.Mutex
 
-set_option linter.deprecated false
-
 namespace IO
 
 /--
@@ -17,7 +15,6 @@ Internal state of an `Channel`.
 
 We maintain the invariant that at all times either `consumers` or `values` is empty.
 -/
-@[deprecated "Use Std.Channel.State from Std.Sync.Channel instead" (since := "2024-12-02")]
 structure Channel.State (α : Type) where
   values : Std.Queue α := ∅
   consumers : Std.Queue (Promise (Option α)) := ∅
@@ -30,14 +27,12 @@ FIFO channel with unbounded buffer, where `recv?` returns a `Task`.
 A channel can be closed.  Once it is closed, all `send`s are ignored, and
 `recv?` returns `none` once the queue is empty.
 -/
-@[deprecated "Use Std.Channel from Std.Sync.Channel instead" (since := "2024-12-02")]
 def Channel (α : Type) : Type := Mutex (Channel.State α)
 
 instance : Nonempty (Channel α) :=
   inferInstanceAs (Nonempty (Mutex _))
 
 /-- Creates a new `Channel`. -/
-@[deprecated "Use Std.Channel.new from Std.Sync.Channel instead" (since := "2024-12-02")]
 def Channel.new : BaseIO (Channel α) :=
   Mutex.new {}
 
@@ -46,7 +41,6 @@ Sends a message on an `Channel`.
 
 This function does not block.
 -/
-@[deprecated "Use Std.Channel.send from Std.Sync.Channel instead" (since := "2024-12-02")]
 def Channel.send (ch : Channel α) (v : α) : BaseIO Unit :=
   ch.atomically do
     let st ← get
@@ -60,7 +54,6 @@ def Channel.send (ch : Channel α) (v : α) : BaseIO Unit :=
 /--
 Closes an `Channel`.
 -/
-@[deprecated "Use Std.Channel.close from Std.Sync.Channel instead" (since := "2024-12-02")]
 def Channel.close (ch : Channel α) : BaseIO Unit :=
   ch.atomically do
     let st ← get
@@ -74,7 +67,6 @@ Every message is only received once.
 
 Returns `none` if the channel is closed and the queue is empty.
 -/
-@[deprecated "Use Std.Channel.recv? from Std.Sync.Channel instead" (since := "2024-12-02")]
 def Channel.recv? (ch : Channel α) : BaseIO (Task (Option α)) :=
   ch.atomically do
     let st ← get
@@ -93,7 +85,6 @@ def Channel.recv? (ch : Channel α) : BaseIO (Task (Option α)) :=
 
 Note that if this function is called twice, each `forAsync` only gets half the messages.
 -/
-@[deprecated "Use Std.Channel.forAsync from Std.Sync.Channel instead" (since := "2024-12-02")]
 partial def Channel.forAsync (f : α → BaseIO Unit) (ch : Channel α)
     (prio : Task.Priority := .default) : BaseIO (Task Unit) := do
   BaseIO.bindTask (prio := prio) (← ch.recv?) fun
@@ -105,13 +96,11 @@ Receives all currently queued messages from the channel.
 
 Those messages are dequeued and will not be returned by `recv?`.
 -/
-@[deprecated "Use Std.Channel.recvAllCurrent from Std.Sync.Channel instead" (since := "2024-12-02")]
 def Channel.recvAllCurrent (ch : Channel α) : BaseIO (Array α) :=
   ch.atomically do
     modifyGet fun st => (st.values.toArray, { st with values := ∅ })
 
 /-- Type tag for synchronous (blocking) operations on a `Channel`. -/
-@[deprecated "Use Std.Channel.Sync from Std.Sync.Channel instead" (since := "2024-12-02")]
 def Channel.Sync := Channel
 
 /--
@@ -121,7 +110,6 @@ For example, `ch.sync.recv?` blocks until the next message,
 and `for msg in ch.sync do ...` iterates synchronously over the channel.
 These functions should only be used in dedicated threads.
 -/
-@[deprecated "Use Std.Channel.sync from Std.Sync.Channel instead" (since := "2024-12-02")]
 def Channel.sync (ch : Channel α) : Channel.Sync α := ch
 
 /--
@@ -130,11 +118,9 @@ Synchronously receives a message from the channel.
 Every message is only received once.
 Returns `none` if the channel is closed and the queue is empty.
 -/
-@[deprecated "Use Std.Channel.Sync.recv? from Std.Sync.Channel instead" (since := "2024-12-02")]
 def Channel.Sync.recv? (ch : Channel.Sync α) : BaseIO (Option α) := do
   IO.wait (← Channel.recv? ch)
 
-@[deprecated "Use Std.Channel.Sync.forIn from Std.Sync.Channel instead" (since := "2024-12-02")]
 private partial def Channel.Sync.forIn [Monad m] [MonadLiftT BaseIO m]
     (ch : Channel.Sync α) (f : α → β → m (ForInStep β)) : β → m β := fun b => do
   match ← ch.recv? with

src/Init/Data/Fin/Basic.lean

@@ -36,6 +36,12 @@ def succ : Fin n → Fin (n + 1)
 
 variable {n : Nat}
 
+/--
+Returns `a` modulo `n + 1` as a `Fin n.succ`.
+-/
+protected def ofNat {n : Nat} (a : Nat) : Fin (n + 1) :=
+  ⟨a % (n+1), Nat.mod_lt _ (Nat.zero_lt_succ _)⟩
+
 /--
 Returns `a` modulo `n` as a `Fin n`.
 
@@ -44,12 +50,9 @@ The assumption `NeZero n` ensures that `Fin n` is nonempty.
 protected def ofNat' (n : Nat) [NeZero n] (a : Nat) : Fin n :=
   ⟨a % n, Nat.mod_lt _ (pos_of_neZero n)⟩
 
-/--
-Returns `a` modulo `n + 1` as a `Fin n.succ`.
--/
-@[deprecated Fin.ofNat' (since := "2024-11-27")]
-protected def ofNat {n : Nat} (a : Nat) : Fin (n + 1) :=
-  ⟨a % (n+1), Nat.mod_lt _ (Nat.zero_lt_succ _)⟩
+-- We intend to deprecate `Fin.ofNat` in favor of `Fin.ofNat'` (and later rename).
+-- This is waiting on https://github.com/leanprover/lean4/pull/5323
+-- attribute [deprecated Fin.ofNat' (since := "2024-09-16")] Fin.ofNat
 
 private theorem mlt {b : Nat} : {a : Nat} → a < n → b % n < n
   | 0,   h => Nat.mod_lt _ h
@@ -176,7 +179,7 @@ protected theorem pos (i : Fin n) : 0 < n :=
 @[inline] def castLE (h : n ≤ m) (i : Fin n) : Fin m := ⟨i, Nat.lt_of_lt_of_le i.2 h⟩
 
 /-- `cast eq i` embeds `i` into an equal `Fin` type. -/
-@[inline] protected def cast (eq : n = m) (i : Fin n) : Fin m := ⟨i, eq ▸ i.2⟩
+@[inline] def cast (eq : n = m) (i : Fin n) : Fin m := ⟨i, eq ▸ i.2⟩
 
 /-- `castAdd m i` embeds `i : Fin n` in `Fin (n+m)`. See also `Fin.natAdd` and `Fin.addNat`. -/
 @[inline] def castAdd (m) : Fin n → Fin (n + m) :=

src/Init/Data/Fin/Fold.lean

@@ -13,17 +13,17 @@ namespace Fin
 /-- Folds over `Fin n` from the left: `foldl 3 f x = f (f (f x 0) 1) 2`. -/
 @[inline] def foldl (n) (f : α → Fin n → α) (init : α) : α := loop init 0 where
   /-- Inner loop for `Fin.foldl`. `Fin.foldl.loop n f x i = f (f (f x i) ...) (n-1)`  -/
-  @[semireducible, specialize] loop (x : α) (i : Nat) : α :=
+  loop (x : α) (i : Nat) : α :=
     if h : i < n then loop (f x ⟨i, h⟩) (i+1) else x
   termination_by n - i
+  decreasing_by decreasing_trivial_pre_omega
 
 /-- Folds over `Fin n` from the right: `foldr 3 f x = f 0 (f 1 (f 2 x))`. -/
-@[inline] def foldr (n) (f : Fin n → α → α) (init : α) : α := loop n (Nat.le_refl n) init where
+@[inline] def foldr (n) (f : Fin n → α → α) (init : α) : α := loop ⟨n, Nat.le_refl n⟩ init where
   /-- Inner loop for `Fin.foldr`. `Fin.foldr.loop n f i x = f 0 (f ... (f (i-1) x))`  -/
-  @[specialize] loop : (i : _) → i ≤ n → α → α
-  | 0, _, x => x
-  | i+1, h, x => loop i (Nat.le_of_lt h) (f ⟨i, h⟩ x)
-  termination_by structural i => i
+  loop : {i // i ≤ n} → α → α
+  | ⟨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:
@@ -47,7 +47,7 @@ Fin.foldlM n f x₀ = do
     pure xₙ
   ```
   -/
-  @[semireducible, specialize] loop (x : α) (i : Nat) : m α := do
+  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
@@ -76,7 +76,7 @@ Fin.foldrM n f xₙ = do
     pure x₀
   ```
   -/
-  @[semireducible, specialize] loop : {i // i ≤ n} → α → m α
+  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⟩
 
@@ -125,7 +125,7 @@ theorem foldrM_loop [Monad m] [LawfulMonad m] (f : Fin (n+1) → α → m α) (x
   | zero =>
     rw [foldrM_loop_zero, foldrM_loop_succ, pure_bind]
     conv => rhs; rw [←bind_pure (f 0 x)]
-    congr; funext
+    congr; funext; exact foldrM_loop_zero ..
   | succ i ih =>
     rw [foldrM_loop_succ, foldrM_loop_succ, bind_assoc]
     congr; funext; exact ih ..
@@ -176,19 +176,17 @@ theorem foldl_eq_foldlM (f : α → Fin n → α) (x) :
 /-! ### foldr -/
 
 theorem foldr_loop_zero (f : Fin n → α → α) (x) :
-    foldr.loop n f 0 (Nat.zero_le _) x = x := by
+    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
+    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 with
-  | zero => simp [foldr_loop_succ, foldr_loop_zero]
-  | succ i ih => rw [foldr_loop_succ, ih]; rfl
+    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 ..

src/Init/Data/Fin/Lemmas.lean

@@ -370,25 +370,25 @@ theorem succ_succ_ne_one (a : Fin n) : Fin.succ (Fin.succ a) ≠ 1 :=
     Fin.castLE mn ∘ Fin.castLE km = Fin.castLE (Nat.le_trans km mn) :=
   funext (castLE_castLE km mn)
 
-@[simp] theorem coe_cast (h : n = m) (i : Fin n) : (i.cast h : Nat) = i := rfl
+@[simp] theorem coe_cast (h : n = m) (i : Fin n) : (cast h i : Nat) = i := rfl
 
-@[simp] theorem cast_last {n' : Nat} {h : n + 1 = n' + 1} : (last n).cast h  = last n' :=
+@[simp] theorem cast_last {n' : Nat} {h : n + 1 = n' + 1} : cast h (last n) = last n' :=
   Fin.ext (by rw [coe_cast, val_last, val_last, Nat.succ.inj h])
 
-@[simp] theorem cast_mk (h : n = m) (i : Nat) (hn : i < n) : Fin.cast h ⟨i, hn⟩ = ⟨i, h ▸ hn⟩ := rfl
+@[simp] theorem cast_mk (h : n = m) (i : Nat) (hn : i < n) : cast h ⟨i, hn⟩ = ⟨i, h ▸ hn⟩ := rfl
 
-@[simp] theorem cast_refl (n : Nat) (h : n = n) : Fin.cast h = id := by
+@[simp] theorem cast_refl (n : Nat) (h : n = n) : cast h = id := by
   ext
   simp
 
 @[simp] theorem cast_trans {k : Nat} (h : n = m) (h' : m = k) {i : Fin n} :
-    (i.cast h).cast h' = i.cast (Eq.trans h h') := rfl
+    cast h' (cast h i) = cast (Eq.trans h h') i := rfl
 
 theorem castLE_of_eq {m n : Nat} (h : m = n) {h' : m ≤ n} : castLE h' = Fin.cast h := rfl
 
 @[simp] theorem coe_castAdd (m : Nat) (i : Fin n) : (castAdd m i : Nat) = i := rfl
 
-@[simp] theorem castAdd_zero : (castAdd 0 : Fin n → Fin (n + 0)) = Fin.cast rfl := rfl
+@[simp] theorem castAdd_zero : (castAdd 0 : Fin n → Fin (n + 0)) = cast rfl := rfl
 
 theorem castAdd_lt {m : Nat} (n : Nat) (i : Fin m) : (castAdd n i : Nat) < m := by simp
 
@@ -406,37 +406,37 @@ theorem castAdd_cast {n n' : Nat} (m : Nat) (i : Fin n') (h : n' = n) :
     castAdd m (Fin.cast h i) = Fin.cast (congrArg (. + m) h) (castAdd m i) := Fin.ext rfl
 
 theorem cast_castAdd_left {n n' m : Nat} (i : Fin n') (h : n' + m = n + m) :
-    (i.castAdd m).cast h = (i.cast (Nat.add_right_cancel h)).castAdd m := rfl
+    cast h (castAdd m i) = castAdd m (cast (Nat.add_right_cancel h) i) := rfl
 
 @[simp] theorem cast_castAdd_right {n m m' : Nat} (i : Fin n) (h : n + m' = n + m) :
-    (i.castAdd m').cast h = i.castAdd m := rfl
+    cast h (castAdd m' i) = castAdd m i := rfl
 
 theorem castAdd_castAdd {m n p : Nat} (i : Fin m) :
-    (i.castAdd n).castAdd p = (i.castAdd (n + p)).cast (Nat.add_assoc ..).symm  := rfl
+    castAdd p (castAdd n i) = cast (Nat.add_assoc ..).symm (castAdd (n + p) i) := rfl
 
 /-- The cast of the successor is the successor of the cast. See `Fin.succ_cast_eq` for rewriting in
 the reverse direction. -/
 @[simp] theorem cast_succ_eq {n' : Nat} (i : Fin n) (h : n.succ = n'.succ) :
-    i.succ.cast h = (i.cast (Nat.succ.inj h)).succ := rfl
+    cast h i.succ = (cast (Nat.succ.inj h) i).succ := rfl
 
 theorem succ_cast_eq {n' : Nat} (i : Fin n) (h : n = n') :
-    (i.cast h).succ = i.succ.cast (by rw [h]) := rfl
+    (cast h i).succ = cast (by rw [h]) i.succ := rfl
 
-@[simp] theorem coe_castSucc (i : Fin n) : (i.castSucc : Nat) = i := rfl
+@[simp] theorem coe_castSucc (i : Fin n) : (Fin.castSucc i : Nat) = i := rfl
 
 @[simp] theorem castSucc_mk (n i : Nat) (h : i < n) : castSucc ⟨i, h⟩ = ⟨i, Nat.lt.step h⟩ := rfl
 
 @[simp] theorem cast_castSucc {n' : Nat} {h : n + 1 = n' + 1} {i : Fin n} :
-    i.castSucc.cast h = (i.cast (Nat.succ.inj h)).castSucc := rfl
+    cast h (castSucc i) = castSucc (cast (Nat.succ.inj h) i) := rfl
 
-theorem castSucc_lt_succ (i : Fin n) : i.castSucc < i.succ :=
+theorem castSucc_lt_succ (i : Fin n) : Fin.castSucc i < i.succ :=
   lt_def.2 <| by simp only [coe_castSucc, val_succ, Nat.lt_succ_self]
 
-theorem le_castSucc_iff {i : Fin (n + 1)} {j : Fin n} : i ≤ j.castSucc ↔ i < j.succ := by
+theorem le_castSucc_iff {i : Fin (n + 1)} {j : Fin n} : i ≤ Fin.castSucc j ↔ i < j.succ := by
   simpa only [lt_def, le_def] using Nat.add_one_le_add_one_iff.symm
 
 theorem castSucc_lt_iff_succ_le {n : Nat} {i : Fin n} {j : Fin (n + 1)} :
-    i.castSucc < j ↔ i.succ ≤ j := .rfl
+    Fin.castSucc i < j ↔ i.succ ≤ j := .rfl
 
 @[simp] theorem succ_last (n : Nat) : (last n).succ = last n.succ := rfl
 
@@ -444,48 +444,48 @@ theorem castSucc_lt_iff_succ_le {n : Nat} {i : Fin n} {j : Fin (n + 1)} :
     i.succ = last (n + 1) ↔ i = last n := by rw [← succ_last, succ_inj]
 
 @[simp] theorem castSucc_castLT (i : Fin (n + 1)) (h : (i : Nat) < n) :
-    (castLT i h).castSucc = i := rfl
+    castSucc (castLT i h) = i := rfl
 
 @[simp] theorem castLT_castSucc {n : Nat} (a : Fin n) (h : (a : Nat) < n) :
-    castLT a.castSucc h = a := rfl
+    castLT (castSucc a) h = a := rfl
 
 @[simp] theorem castSucc_lt_castSucc_iff {a b : Fin n} :
-    a.castSucc < b.castSucc ↔ a < b := .rfl
+    Fin.castSucc a < Fin.castSucc b ↔ a < b := .rfl
 
-theorem castSucc_inj {a b : Fin n} : a.castSucc = b.castSucc ↔ a = b := by simp [Fin.ext_iff]
+theorem castSucc_inj {a b : Fin n} : castSucc a = castSucc b ↔ a = b := by simp [Fin.ext_iff]
 
-theorem castSucc_lt_last (a : Fin n) : a.castSucc < last n := a.is_lt
+theorem castSucc_lt_last (a : Fin n) : castSucc a < last n := a.is_lt
 
 @[simp] theorem castSucc_zero : castSucc (0 : Fin (n + 1)) = 0 := rfl
 
 @[simp] theorem castSucc_one {n : Nat} : castSucc (1 : Fin (n + 2)) = 1 := rfl
 
 /-- `castSucc i` is positive when `i` is positive -/
-theorem castSucc_pos {i : Fin (n + 1)} (h : 0 < i) : 0 < i.castSucc := by
+theorem castSucc_pos {i : Fin (n + 1)} (h : 0 < i) : 0 < castSucc i := by
   simpa [lt_def] using h
 
-@[simp] theorem castSucc_eq_zero_iff {a : Fin (n + 1)} : a.castSucc = 0 ↔ a = 0 := by simp [Fin.ext_iff]
+@[simp] theorem castSucc_eq_zero_iff {a : Fin (n + 1)} : castSucc a = 0 ↔ a = 0 := by simp [Fin.ext_iff]
 
-theorem castSucc_ne_zero_iff {a : Fin (n + 1)} : a.castSucc ≠ 0 ↔ a ≠ 0 :=
+theorem castSucc_ne_zero_iff {a : Fin (n + 1)} : castSucc a ≠ 0 ↔ a ≠ 0 :=
   not_congr <| castSucc_eq_zero_iff
 
 theorem castSucc_fin_succ (n : Nat) (j : Fin n) :
-    j.succ.castSucc = (j.castSucc).succ := by simp [Fin.ext_iff]
+    castSucc (Fin.succ j) = Fin.succ (castSucc j) := by simp [Fin.ext_iff]
 
 @[simp]
-theorem coeSucc_eq_succ {a : Fin n} : a.castSucc + 1 = a.succ := by
+theorem coeSucc_eq_succ {a : Fin n} : castSucc a + 1 = a.succ := by
   cases n
   · exact a.elim0
   · simp [Fin.ext_iff, add_def, Nat.mod_eq_of_lt (Nat.succ_lt_succ a.is_lt)]
 
-theorem lt_succ {a : Fin n} : a.castSucc < a.succ := by
+theorem lt_succ {a : Fin n} : castSucc a < a.succ := by
   rw [castSucc, lt_def, coe_castAdd, val_succ]; exact Nat.lt_succ_self a.val
 
 theorem exists_castSucc_eq {n : Nat} {i : Fin (n + 1)} : (∃ j, castSucc j = i) ↔ i ≠ last n :=
   ⟨fun ⟨j, hj⟩ => hj ▸ Fin.ne_of_lt j.castSucc_lt_last,
    fun hi => ⟨i.castLT <| Fin.val_lt_last hi, rfl⟩⟩
 
-theorem succ_castSucc {n : Nat} (i : Fin n) : i.castSucc.succ = i.succ.castSucc := rfl
+theorem succ_castSucc {n : Nat} (i : Fin n) : i.castSucc.succ = castSucc i.succ := rfl
 
 @[simp] theorem coe_addNat (m : Nat) (i : Fin n) : (addNat i m : Nat) = i + m := rfl
 
@@ -502,17 +502,17 @@ theorem le_coe_addNat (m : Nat) (i : Fin n) : m ≤ addNat i m :=
     addNat ⟨i, hi⟩ n = ⟨i + n, Nat.add_lt_add_right hi n⟩ := rfl
 
 @[simp] theorem cast_addNat_zero {n n' : Nat} (i : Fin n) (h : n + 0 = n') :
-    (addNat i 0).cast h = i.cast ((Nat.add_zero _).symm.trans h) := rfl
+    cast h (addNat i 0) = cast ((Nat.add_zero _).symm.trans h) i := rfl
 
 /-- For rewriting in the reverse direction, see `Fin.cast_addNat_left`. -/
 theorem addNat_cast {n n' m : Nat} (i : Fin n') (h : n' = n) :
-    addNat (i.cast h) m = (addNat i m).cast (congrArg (. + m) h) := rfl
+    addNat (cast h i) m = cast (congrArg (. + m) h) (addNat i m) := rfl
 
 theorem cast_addNat_left {n n' m : Nat} (i : Fin n') (h : n' + m = n + m) :
-    (addNat i m).cast h = addNat (i.cast (Nat.add_right_cancel h)) m := rfl
+    cast h (addNat i m) = addNat (cast (Nat.add_right_cancel h) i) m := rfl
 
 @[simp] theorem cast_addNat_right {n m m' : Nat} (i : Fin n) (h : n + m' = n + m) :
-    (addNat i m').cast h = addNat i m :=
+    cast h (addNat i m') = addNat i m :=
   Fin.ext <| (congrArg ((· + ·) (i : Nat)) (Nat.add_left_cancel h) : _)
 
 @[simp] theorem coe_natAdd (n : Nat) {m : Nat} (i : Fin m) : (natAdd n i : Nat) = n + i := rfl
@@ -522,46 +522,46 @@ theorem cast_addNat_left {n n' m : Nat} (i : Fin n') (h : n' + m = n + m) :
 
 theorem le_coe_natAdd (m : Nat) (i : Fin n) : m ≤ natAdd m i := Nat.le_add_right ..
 
-@[simp] theorem natAdd_zero {n : Nat} : natAdd 0 = Fin.cast (Nat.zero_add n).symm := by ext; simp
+@[simp] theorem natAdd_zero {n : Nat} : natAdd 0 = cast (Nat.zero_add n).symm := by ext; simp
 
 /-- For rewriting in the reverse direction, see `Fin.cast_natAdd_right`. -/
 theorem natAdd_cast {n n' : Nat} (m : Nat) (i : Fin n') (h : n' = n) :
-    natAdd m (i.cast h) = (natAdd m i).cast (congrArg _ h) := rfl
+    natAdd m (cast h i) = cast (congrArg _ h) (natAdd m i) := rfl
 
 theorem cast_natAdd_right {n n' m : Nat} (i : Fin n') (h : m + n' = m + n) :
-    (natAdd m i).cast h  = natAdd m (i.cast (Nat.add_left_cancel h)) := rfl
+    cast h (natAdd m i) = natAdd m (cast (Nat.add_left_cancel h) i) := rfl
 
 @[simp] theorem cast_natAdd_left {n m m' : Nat} (i : Fin n) (h : m' + n = m + n) :
-    (natAdd m' i).cast h = natAdd m i :=
+    cast h (natAdd m' i) = natAdd m i :=
   Fin.ext <| (congrArg (· + (i : Nat)) (Nat.add_right_cancel h) : _)
 
 theorem castAdd_natAdd (p m : Nat) {n : Nat} (i : Fin n) :
-    castAdd p (natAdd m i) = (natAdd m (castAdd p i)).cast (Nat.add_assoc ..).symm := rfl
+    castAdd p (natAdd m i) = cast (Nat.add_assoc ..).symm (natAdd m (castAdd p i)) := rfl
 
 theorem natAdd_castAdd (p m : Nat) {n : Nat} (i : Fin n) :
-    natAdd m (castAdd p i) = (castAdd p (natAdd m i)).cast (Nat.add_assoc ..) := rfl
+    natAdd m (castAdd p i) = cast (Nat.add_assoc ..) (castAdd p (natAdd m i)) := rfl
 
 theorem natAdd_natAdd (m n : Nat) {p : Nat} (i : Fin p) :
-    natAdd m (natAdd n i) = (natAdd (m + n) i).cast (Nat.add_assoc ..) :=
+    natAdd m (natAdd n i) = cast (Nat.add_assoc ..) (natAdd (m + n) i) :=
   Fin.ext <| (Nat.add_assoc ..).symm
 
 @[simp]
 theorem cast_natAdd_zero {n n' : Nat} (i : Fin n) (h : 0 + n = n') :
-    (natAdd 0 i).cast h = i.cast ((Nat.zero_add _).symm.trans h) :=
+    cast h (natAdd 0 i) = cast ((Nat.zero_add _).symm.trans h) i :=
   Fin.ext <| Nat.zero_add _
 
 @[simp]
 theorem cast_natAdd (n : Nat) {m : Nat} (i : Fin m) :
-    (natAdd n i).cast (Nat.add_comm ..) = addNat i n := Fin.ext <| Nat.add_comm ..
+    cast (Nat.add_comm ..) (natAdd n i) = addNat i n := Fin.ext <| Nat.add_comm ..
 
 @[simp]
 theorem cast_addNat {n : Nat} (m : Nat) (i : Fin n) :
-    (addNat i m).cast (Nat.add_comm ..) = natAdd m i := Fin.ext <| Nat.add_comm ..
+    cast (Nat.add_comm ..) (addNat i m) = natAdd m i := Fin.ext <| Nat.add_comm ..
 
 @[simp] theorem natAdd_last {m n : Nat} : natAdd n (last m) = last (n + m) := rfl
 
 @[simp] theorem addNat_last (n : Nat) :
-    addNat (last n) m = (last (n + m)).cast (by omega) := by
+    addNat (last n) m = cast (by omega) (last (n + m)) := by
   ext
   simp
 
@@ -657,7 +657,7 @@ theorem pred_add_one (i : Fin (n + 2)) (h : (i : Nat) < n + 1) :
     subNat m (addNat i m) h = i := Fin.ext <| Nat.add_sub_cancel i m
 
 @[simp] theorem natAdd_subNat_cast {i : Fin (n + m)} (h : n ≤ i) :
-    natAdd n (subNat n (i.cast (Nat.add_comm ..)) h) = i := by simp [← cast_addNat]
+    natAdd n (subNat n (cast (Nat.add_comm ..) i) h) = i := by simp [← cast_addNat]
 
 /-! ### recursion and induction principles -/
 

src/Init/Data/Float.lean

@@ -31,7 +31,7 @@ opaque floatSpec : FloatSpec := {
 structure Float where
   val : floatSpec.float
 
-instance : Nonempty Float := ⟨{ val := floatSpec.val }⟩
+instance : Inhabited Float := ⟨{ val := floatSpec.val }⟩
 
 @[extern "lean_float_add"] opaque Float.add : Float → Float → Float
 @[extern "lean_float_sub"] opaque Float.sub : Float → Float → Float
@@ -136,9 +136,6 @@ instance : ToString Float where
 
 @[extern "lean_uint64_to_float"] opaque UInt64.toFloat (n : UInt64) : Float
 
-instance : Inhabited Float where
-  default := UInt64.toFloat 0
-
 instance : Repr Float where
   reprPrec n prec := if n < UInt64.toFloat 0 then Repr.addAppParen (toString n) prec else toString n
 

src/Init/Data/Float32.lean

@@ -1,180 +0,0 @@
-/-
-Copyright (c) 2023 Amazon.com, Inc. or its affiliates. All Rights Reserved.
-Released under Apache 2.0 license as described in the file LICENSE.
-Authors: Leonardo de Moura
--/
-prelude
-import Init.Core
-import Init.Data.Int.Basic
-import Init.Data.ToString.Basic
-import Init.Data.Float
-
-/-
-#exit -- TODO: Remove after update stage0
-
--- Just show FloatSpec is inhabited.
-opaque float32Spec : FloatSpec := {
-  float := Unit,
-  val   := (),
-  lt    := fun _ _ => True,
-  le    := fun _ _ => True,
-  decLt := fun _ _ => inferInstanceAs (Decidable True),
-  decLe := fun _ _ => inferInstanceAs (Decidable True)
-}
-
-/-- Native floating point type, corresponding to the IEEE 754 *binary32* format
-(`float` in C or `f32` in Rust). -/
-structure Float32 where
-  val : float32Spec.float
-
-instance : Nonempty Float32 := ⟨{ val := float32Spec.val }⟩
-
-@[extern "lean_float32_add"] opaque Float32.add : Float32 → Float32 → Float32
-@[extern "lean_float32_sub"] opaque Float32.sub : Float32 → Float32 → Float32
-@[extern "lean_float32_mul"] opaque Float32.mul : Float32 → Float32 → Float32
-@[extern "lean_float32_div"] opaque Float32.div : Float32 → Float32 → Float32
-@[extern "lean_float32_negate"] opaque Float32.neg : Float32 → Float32
-
-set_option bootstrap.genMatcherCode false
-def Float32.lt : Float32 → Float32 → Prop := fun a b =>
-  match a, b with
-  | ⟨a⟩, ⟨b⟩ => float32Spec.lt a b
-
-def Float32.le : Float32 → Float32 → Prop := fun a b =>
-  float32Spec.le a.val b.val
-
-/--
-Raw transmutation from `UInt32`.
-
-Float32s and UInts have the same endianness on all supported platforms.
-IEEE 754 very precisely specifies the bit layout of floats.
--/
-@[extern "lean_float32_of_bits"] opaque Float32.ofBits : UInt32 → Float32
-
-/--
-Raw transmutation to `UInt32`.
-
-Float32s and UInts have the same endianness on all supported platforms.
-IEEE 754 very precisely specifies the bit layout of floats.
-
-Note that this function is distinct from `Float32.toUInt32`, which attempts
-to preserve the numeric value, and not the bitwise value.
--/
-@[extern "lean_float32_to_bits"] opaque Float32.toBits : Float32 → UInt32
-
-instance : Add Float32 := ⟨Float32.add⟩
-instance : Sub Float32 := ⟨Float32.sub⟩
-instance : Mul Float32 := ⟨Float32.mul⟩
-instance : Div Float32 := ⟨Float32.div⟩
-instance : Neg Float32 := ⟨Float32.neg⟩
-instance : LT Float32  := ⟨Float32.lt⟩
-instance : LE Float32  := ⟨Float32.le⟩
-
-/-- Note: this is not reflexive since `NaN != NaN`.-/
-@[extern "lean_float32_beq"] opaque Float32.beq (a b : Float32) : Bool
-
-instance : BEq Float32 := ⟨Float32.beq⟩
-
-@[extern "lean_float32_decLt"] opaque Float32.decLt (a b : Float32) : Decidable (a < b) :=
-  match a, b with
-  | ⟨a⟩, ⟨b⟩ => float32Spec.decLt a b
-
-@[extern "lean_float32_decLe"] opaque Float32.decLe (a b : Float32) : Decidable (a ≤ b) :=
-  match a, b with
-  | ⟨a⟩, ⟨b⟩ => float32Spec.decLe a b
-
-instance float32DecLt (a b : Float32) : Decidable (a < b) := Float32.decLt a b
-instance float32DecLe (a b : Float32) : Decidable (a ≤ b) := Float32.decLe a b
-
-@[extern "lean_float32_to_string"] opaque Float32.toString : Float32 → String
-/-- If the given float is non-negative, truncates the value to the nearest non-negative integer.
-If negative or NaN, returns `0`.
-If larger than the maximum value for `UInt8` (including Inf), returns the maximum value of `UInt8`
-(i.e. `UInt8.size - 1`).
--/
-@[extern "lean_float32_to_uint8"] opaque Float32.toUInt8 : Float32 → UInt8
-/-- If the given float is non-negative, truncates the value to the nearest non-negative integer.
-If negative or NaN, returns `0`.
-If larger than the maximum value for `UInt16` (including Inf), returns the maximum value of `UInt16`
-(i.e. `UInt16.size - 1`).
--/
-@[extern "lean_float32_to_uint16"] opaque Float32.toUInt16 : Float32 → UInt16
-/-- If the given float is non-negative, truncates the value to the nearest non-negative integer.
-If negative or NaN, returns `0`.
-If larger than the maximum value for `UInt32` (including Inf), returns the maximum value of `UInt32`
-(i.e. `UInt32.size - 1`).
--/
-@[extern "lean_float32_to_uint32"] opaque Float32.toUInt32 : Float32 → UInt32
-/-- If the given float is non-negative, truncates the value to the nearest non-negative integer.
-If negative or NaN, returns `0`.
-If larger than the maximum value for `UInt64` (including Inf), returns the maximum value of `UInt64`
-(i.e. `UInt64.size - 1`).
--/
-@[extern "lean_float32_to_uint64"] opaque Float32.toUInt64 : Float32 → UInt64
-/-- If the given float is non-negative, truncates the value to the nearest non-negative integer.
-If negative or NaN, returns `0`.
-If larger than the maximum value for `USize` (including Inf), returns the maximum value of `USize`
-(i.e. `USize.size - 1`). This value is platform dependent).
--/
-@[extern "lean_float32_to_usize"] opaque Float32.toUSize : Float32 → USize
-
-@[extern "lean_float32_isnan"] opaque Float32.isNaN : Float32 → Bool
-@[extern "lean_float32_isfinite"] opaque Float32.isFinite : Float32 → Bool
-@[extern "lean_float32_isinf"] opaque Float32.isInf : Float32 → Bool
-/-- Splits the given float `x` into a significand/exponent pair `(s, i)`
-such that `x = s * 2^i` where `s ∈ (-1;-0.5] ∪ [0.5; 1)`.
-Returns an undefined value if `x` is not finite.
--/
-@[extern "lean_float32_frexp"] opaque Float32.frExp : Float32 → Float32 × Int
-
-instance : ToString Float32 where
-  toString := Float32.toString
-
-@[extern "lean_uint64_to_float"] opaque UInt64.toFloat32 (n : UInt64) : Float32
-
-instance : Inhabited Float32 where
-  default := UInt64.toFloat32 0
-
-instance : Repr Float32 where
-  reprPrec n prec := if n < UInt64.toFloat32 0 then Repr.addAppParen (toString n) prec else toString n
-
-instance : ReprAtom Float32  := ⟨⟩
-
-@[extern "sinf"] opaque Float32.sin : Float32 → Float32
-@[extern "cosf"] opaque Float32.cos : Float32 → Float32
-@[extern "tanf"] opaque Float32.tan : Float32 → Float32
-@[extern "asinf"] opaque Float32.asin : Float32 → Float32
-@[extern "acosf"] opaque Float32.acos : Float32 → Float32
-@[extern "atanf"] opaque Float32.atan : Float32 → Float32
-@[extern "atan2f"] opaque Float32.atan2 : Float32 → Float32 → Float32
-@[extern "sinhf"] opaque Float32.sinh : Float32 → Float32
-@[extern "coshf"] opaque Float32.cosh : Float32 → Float32
-@[extern "tanhf"] opaque Float32.tanh : Float32 → Float32
-@[extern "asinhf"] opaque Float32.asinh : Float32 → Float32
-@[extern "acoshf"] opaque Float32.acosh : Float32 → Float32
-@[extern "atanhf"] opaque Float32.atanh : Float32 → Float32
-@[extern "expf"] opaque Float32.exp : Float32 → Float32
-@[extern "exp2f"] opaque Float32.exp2 : Float32 → Float32
-@[extern "logf"] opaque Float32.log : Float32 → Float32
-@[extern "log2f"] opaque Float32.log2 : Float32 → Float32
-@[extern "log10f"] opaque Float32.log10 : Float32 → Float32
-@[extern "powf"] opaque Float32.pow : Float32 → Float32 → Float32
-@[extern "sqrtf"] opaque Float32.sqrt : Float32 → Float32
-@[extern "cbrtf"] opaque Float32.cbrt : Float32 → Float32
-@[extern "ceilf"] opaque Float32.ceil : Float32 → Float32
-@[extern "floorf"] opaque Float32.floor : Float32 → Float32
-@[extern "roundf"] opaque Float32.round : Float32 → Float32
-@[extern "fabsf"] opaque Float32.abs : Float32 → Float32
-
-instance : HomogeneousPow Float32 := ⟨Float32.pow⟩
-
-instance : Min Float32 := minOfLe
-
-instance : Max Float32 := maxOfLe
-
-/--
-Efficiently computes `x * 2^i`.
--/
-@[extern "lean_float32_scaleb"]
-opaque Float32.scaleB (x : Float32) (i : @& Int) : Float32
--/

src/Init/Data/Int/Bitwise/Lemmas.lean

@@ -34,8 +34,4 @@ theorem shiftRight_eq_div_pow (m : Int) (n : Nat) :
 theorem zero_shiftRight (n : Nat) : (0 : Int) >>> n = 0 := by
   simp [Int.shiftRight_eq_div_pow]
 
-@[simp]
-theorem shiftRight_zero (n : Int) : n >>> 0 = n := by
-  simp [Int.shiftRight_eq_div_pow]
-
 end Int

src/Init/Data/Int/DivMod.lean

@@ -29,8 +29,6 @@ At that time, we did not rename `div` and `mod` to `tdiv` and `tmod` (along with
 In September 2024, we decided to do this rename (with deprecations in place),
 and later we intend to rename `ediv` and `emod` to `div` and `mod`, as nearly all users will only
 ever need to use these functions and their associated lemmas.
-
-In December 2024, we removed `tdiv` and `tmod`, but have not yet renamed `ediv` and `emod`.
 -/
 
 /-! ### T-rounding division -/
@@ -73,6 +71,8 @@ def tdiv : (@& Int) → (@& Int) → Int
   | -[m +1], ofNat n => -ofNat (succ m / n)
   | -[m +1], -[n +1] =>  ofNat (succ m / succ n)
 
+@[deprecated tdiv (since := "2024-09-11")] abbrev div := tdiv
+
 /-- Integer modulo. This function uses the
   [*"T-rounding"*][t-rounding] (**T**runcation-rounding) convention
   to pair with `Int.tdiv`, meaning that `tmod a b + b * (tdiv a b) = a`
@@ -107,6 +107,8 @@ def tmod : (@& Int) → (@& Int) → Int
   | -[m +1], ofNat n => -ofNat (succ m % n)
   | -[m +1], -[n +1] => -ofNat (succ m % succ n)
 
+@[deprecated tmod (since := "2024-09-11")] abbrev mod := tmod
+
 /-! ### F-rounding division
 This pair satisfies `fdiv x y = floor (x / y)`.
 -/
@@ -249,6 +251,8 @@ instance : Mod Int where
 
 theorem ofNat_tdiv (m n : Nat) : ↑(m / n) = tdiv ↑m ↑n := rfl
 
+@[deprecated ofNat_tdiv (since := "2024-09-11")] abbrev ofNat_div := ofNat_tdiv
+
 theorem ofNat_fdiv : ∀ m n : Nat, ↑(m / n) = fdiv ↑m ↑n
   | 0, _ => by simp [fdiv]
   | succ _, _ => rfl

src/Init/Data/Int/DivModLemmas.lean

@@ -125,7 +125,7 @@ theorem eq_one_of_mul_eq_one_right {a b : Int} (H : 0 ≤ a) (H' : a * b = 1) :
   eq_one_of_dvd_one H ⟨b, H'.symm⟩
 
 theorem eq_one_of_mul_eq_one_left {a b : Int} (H : 0 ≤ b) (H' : a * b = 1) : b = 1 :=
-  eq_one_of_mul_eq_one_right (b := a) H <| by rw [Int.mul_comm, H']
+  eq_one_of_mul_eq_one_right H <| by rw [Int.mul_comm, H']
 
 /-! ### *div zero  -/
 
@@ -1315,3 +1315,65 @@ theorem bmod_natAbs_plus_one (x : Int) (w : 1 < x.natAbs) : bmod x (x.natAbs + 1
           all_goals decide
     · exact ofNat_nonneg x
     · exact succ_ofNat_pos (x + 1)
+
+/-! ### Deprecations -/
+
+@[deprecated Int.zero_tdiv (since := "2024-09-11")] protected abbrev zero_div := @Int.zero_tdiv
+@[deprecated Int.tdiv_zero (since := "2024-09-11")] protected abbrev div_zero := @Int.tdiv_zero
+@[deprecated tdiv_eq_ediv (since := "2024-09-11")] abbrev div_eq_ediv := @tdiv_eq_ediv
+@[deprecated fdiv_eq_tdiv (since := "2024-09-11")] abbrev fdiv_eq_div := @fdiv_eq_tdiv
+@[deprecated zero_tmod (since := "2024-09-11")] abbrev zero_mod := @zero_tmod
+@[deprecated tmod_zero (since := "2024-09-11")] abbrev mod_zero := @tmod_zero
+@[deprecated tmod_add_tdiv (since := "2024-09-11")] abbrev mod_add_div := @tmod_add_tdiv
+@[deprecated tdiv_add_tmod (since := "2024-09-11")] abbrev div_add_mod := @tdiv_add_tmod
+@[deprecated tmod_add_tdiv' (since := "2024-09-11")] abbrev mod_add_div' := @tmod_add_tdiv'
+@[deprecated tdiv_add_tmod' (since := "2024-09-11")] abbrev div_add_mod' := @tdiv_add_tmod'
+@[deprecated tmod_def (since := "2024-09-11")] abbrev mod_def := @tmod_def
+@[deprecated tmod_eq_emod (since := "2024-09-11")] abbrev mod_eq_emod := @tmod_eq_emod
+@[deprecated fmod_eq_tmod (since := "2024-09-11")] abbrev fmod_eq_mod := @fmod_eq_tmod
+@[deprecated Int.tdiv_one (since := "2024-09-11")] protected abbrev div_one := @Int.tdiv_one
+@[deprecated Int.tdiv_neg (since := "2024-09-11")] protected abbrev div_neg := @Int.tdiv_neg
+@[deprecated Int.neg_tdiv (since := "2024-09-11")] protected abbrev neg_div := @Int.neg_tdiv
+@[deprecated Int.neg_tdiv_neg (since := "2024-09-11")] protected abbrev neg_div_neg := @Int.neg_tdiv_neg
+@[deprecated Int.tdiv_nonneg (since := "2024-09-11")] protected abbrev div_nonneg := @Int.tdiv_nonneg
+@[deprecated Int.tdiv_nonpos (since := "2024-09-11")] protected abbrev div_nonpos := @Int.tdiv_nonpos
+@[deprecated Int.tdiv_eq_zero_of_lt (since := "2024-09-11")] abbrev div_eq_zero_of_lt := @Int.tdiv_eq_zero_of_lt
+@[deprecated Int.mul_tdiv_cancel (since := "2024-09-11")] protected abbrev mul_div_cancel := @Int.mul_tdiv_cancel
+@[deprecated Int.mul_tdiv_cancel_left (since := "2024-09-11")] protected abbrev mul_div_cancel_left := @Int.mul_tdiv_cancel_left
+@[deprecated Int.tdiv_self (since := "2024-09-11")] protected abbrev div_self := @Int.tdiv_self
+@[deprecated Int.mul_tdiv_cancel_of_tmod_eq_zero (since := "2024-09-11")] abbrev mul_div_cancel_of_mod_eq_zero := @Int.mul_tdiv_cancel_of_tmod_eq_zero
+@[deprecated Int.tdiv_mul_cancel_of_tmod_eq_zero (since := "2024-09-11")] abbrev div_mul_cancel_of_mod_eq_zero := @Int.tdiv_mul_cancel_of_tmod_eq_zero
+@[deprecated Int.dvd_of_tmod_eq_zero (since := "2024-09-11")] abbrev dvd_of_mod_eq_zero := @Int.dvd_of_tmod_eq_zero
+@[deprecated Int.mul_tdiv_assoc (since := "2024-09-11")] protected abbrev mul_div_assoc := @Int.mul_tdiv_assoc
+@[deprecated Int.mul_tdiv_assoc' (since := "2024-09-11")] protected abbrev mul_div_assoc' := @Int.mul_tdiv_assoc'
+@[deprecated Int.tdiv_dvd_tdiv (since := "2024-09-11")] abbrev div_dvd_div := @Int.tdiv_dvd_tdiv
+@[deprecated Int.natAbs_tdiv (since := "2024-09-11")] abbrev natAbs_div := @Int.natAbs_tdiv
+@[deprecated Int.tdiv_eq_of_eq_mul_right (since := "2024-09-11")] protected abbrev div_eq_of_eq_mul_right := @Int.tdiv_eq_of_eq_mul_right
+@[deprecated Int.eq_tdiv_of_mul_eq_right (since := "2024-09-11")] protected abbrev eq_div_of_mul_eq_right := @Int.eq_tdiv_of_mul_eq_right
+@[deprecated Int.ofNat_tmod (since := "2024-09-11")] abbrev ofNat_mod := @Int.ofNat_tmod
+@[deprecated Int.tmod_one (since := "2024-09-11")] abbrev mod_one := @Int.tmod_one
+@[deprecated Int.tmod_eq_of_lt (since := "2024-09-11")] abbrev mod_eq_of_lt := @Int.tmod_eq_of_lt
+@[deprecated Int.tmod_lt_of_pos (since := "2024-09-11")] abbrev mod_lt_of_pos := @Int.tmod_lt_of_pos
+@[deprecated Int.tmod_nonneg (since := "2024-09-11")] abbrev mod_nonneg := @Int.tmod_nonneg
+@[deprecated Int.tmod_neg (since := "2024-09-11")] abbrev mod_neg := @Int.tmod_neg
+@[deprecated Int.mul_tmod_left (since := "2024-09-11")] abbrev mul_mod_left := @Int.mul_tmod_left
+@[deprecated Int.mul_tmod_right (since := "2024-09-11")] abbrev mul_mod_right := @Int.mul_tmod_right
+@[deprecated Int.tmod_eq_zero_of_dvd (since := "2024-09-11")] abbrev mod_eq_zero_of_dvd := @Int.tmod_eq_zero_of_dvd
+@[deprecated Int.dvd_iff_tmod_eq_zero (since := "2024-09-11")] abbrev dvd_iff_mod_eq_zero := @Int.dvd_iff_tmod_eq_zero
+@[deprecated Int.neg_mul_tmod_right (since := "2024-09-11")] abbrev neg_mul_mod_right := @Int.neg_mul_tmod_right
+@[deprecated Int.neg_mul_tmod_left (since := "2024-09-11")] abbrev neg_mul_mod_left := @Int.neg_mul_tmod_left
+@[deprecated Int.tdiv_mul_cancel (since := "2024-09-11")] protected abbrev div_mul_cancel := @Int.tdiv_mul_cancel
+@[deprecated Int.mul_tdiv_cancel' (since := "2024-09-11")] protected abbrev mul_div_cancel' := @Int.mul_tdiv_cancel'
+@[deprecated Int.eq_mul_of_tdiv_eq_right (since := "2024-09-11")] protected abbrev eq_mul_of_div_eq_right := @Int.eq_mul_of_tdiv_eq_right
+@[deprecated Int.tmod_self (since := "2024-09-11")] abbrev mod_self := @Int.tmod_self
+@[deprecated Int.neg_tmod_self (since := "2024-09-11")] abbrev neg_mod_self := @Int.neg_tmod_self
+@[deprecated Int.lt_tdiv_add_one_mul_self (since := "2024-09-11")] abbrev lt_div_add_one_mul_self := @Int.lt_tdiv_add_one_mul_self
+@[deprecated Int.tdiv_eq_iff_eq_mul_right (since := "2024-09-11")] protected abbrev div_eq_iff_eq_mul_right := @Int.tdiv_eq_iff_eq_mul_right
+@[deprecated Int.tdiv_eq_iff_eq_mul_left (since := "2024-09-11")] protected abbrev div_eq_iff_eq_mul_left := @Int.tdiv_eq_iff_eq_mul_left
+@[deprecated Int.eq_mul_of_tdiv_eq_left (since := "2024-09-11")] protected abbrev eq_mul_of_div_eq_left := @Int.eq_mul_of_tdiv_eq_left
+@[deprecated Int.tdiv_eq_of_eq_mul_left (since := "2024-09-11")] protected abbrev div_eq_of_eq_mul_left := @Int.tdiv_eq_of_eq_mul_left
+@[deprecated Int.eq_zero_of_tdiv_eq_zero (since := "2024-09-11")] protected abbrev eq_zero_of_div_eq_zero := @Int.eq_zero_of_tdiv_eq_zero
+@[deprecated Int.tdiv_left_inj (since := "2024-09-11")] protected abbrev div_left_inj := @Int.tdiv_left_inj
+@[deprecated Int.tdiv_sign (since := "2024-09-11")] abbrev div_sign := @Int.tdiv_sign
+@[deprecated Int.sign_eq_tdiv_abs (since := "2024-09-11")] protected abbrev sign_eq_div_abs := @Int.sign_eq_tdiv_abs
+@[deprecated Int.tdiv_eq_ediv_of_dvd (since := "2024-09-11")] abbrev div_eq_ediv_of_dvd := @Int.tdiv_eq_ediv_of_dvd

src/Init/Data/List.lean

@@ -24,7 +24,5 @@ import Init.Data.List.Zip
 import Init.Data.List.Perm
 import Init.Data.List.Sort
 import Init.Data.List.ToArray
-import Init.Data.List.ToArrayImpl
 import Init.Data.List.MapIdx
 import Init.Data.List.OfFn
-import Init.Data.List.FinRange

src/Init/Data/List/Attach.lean

@@ -13,7 +13,7 @@ namespace List
   `a : α` satisfying `P`, then `pmap f l h` is essentially the same as `map f l`
   but is defined only when all members of `l` satisfy `P`, using the proof
   to apply `f`. -/
-def pmap {P : α → Prop} (f : ∀ a, P a → β) : ∀ l : List α, (H : ∀ a ∈ l, P a) → List β
+@[simp] def pmap {P : α → Prop} (f : ∀ a, P a → β) : ∀ l : List α, (H : ∀ a ∈ l, P a) → List β
   | [], _ => []
   | a :: l, H => f a (forall_mem_cons.1 H).1 :: pmap f l (forall_mem_cons.1 H).2
 
@@ -46,11 +46,6 @@ Unsafe implementation of `attachWith`, taking advantage of the fact that the rep
   | cons _ L', hL' => congrArg _ <| go L' fun _ hx => hL' (.tail _ hx)
   exact go L h'
 
-@[simp] theorem pmap_nil {P : α → Prop} (f : ∀ a, P a → β) : pmap f [] (by simp) = [] := rfl
-
-@[simp] theorem pmap_cons {P : α → Prop} (f : ∀ a, P a → β) (a : α) (l : List α) (h : ∀ b ∈ a :: l, P b) :
-    pmap f (a :: l) h = f a (forall_mem_cons.1 h).1 :: pmap f l (forall_mem_cons.1 h).2 := rfl
-
 @[simp] theorem attach_nil : ([] : List α).attach = [] := rfl
 
 @[simp] theorem attachWith_nil : ([] : List α).attachWith P H = [] := rfl
@@ -153,7 +148,7 @@ theorem mem_pmap_of_mem {p : α → Prop} {f : ∀ a, p a → β} {l H} {a} (h :
   exact ⟨a, h, rfl⟩
 
 @[simp]
-theorem length_pmap {p : α → Prop} {f : ∀ a, p a → β} {l H} : (pmap f l H).length = l.length := by
+theorem length_pmap {p : α → Prop} {f : ∀ a, p a → β} {l H} : length (pmap f l H) = length l := by
   induction l
   · rfl
   · simp only [*, pmap, length]
@@ -204,7 +199,7 @@ theorem attachWith_ne_nil_iff {l : List α} {P : α → Prop} {H : ∀ a ∈ l,
 
 @[simp]
 theorem getElem?_pmap {p : α → Prop} (f : ∀ a, p a → β) {l : List α} (h : ∀ a ∈ l, p a) (n : Nat) :
-    (pmap f l h)[n]? = Option.pmap f l[n]? fun x H => h x (mem_of_getElem? H) := by
+    (pmap f l h)[n]? = Option.pmap f l[n]? fun x H => h x (getElem?_mem H) := by
   induction l generalizing n with
   | nil => simp
   | cons hd tl hl =>
@@ -220,7 +215,7 @@ theorem getElem?_pmap {p : α → Prop} (f : ∀ a, p a → β) {l : List α} (h
       · simp_all
 
 theorem get?_pmap {p : α → Prop} (f : ∀ a, p a → β) {l : List α} (h : ∀ a ∈ l, p a) (n : Nat) :
-    get? (pmap f l h) n = Option.pmap f (get? l n) fun x H => h x (mem_of_get? H) := by
+    get? (pmap f l h) n = Option.pmap f (get? l n) fun x H => h x (get?_mem H) := by
   simp only [get?_eq_getElem?]
   simp [getElem?_pmap, h]
 
@@ -243,18 +238,18 @@ theorem get_pmap {p : α → Prop} (f : ∀ a, p a → β) {l : List α} (h :
     (hn : n < (pmap f l h).length) :
     get (pmap f l h) ⟨n, hn⟩ =
       f (get l ⟨n, @length_pmap _ _ p f l h ▸ hn⟩)
-        (h _ (getElem_mem (@length_pmap _ _ p f l h ▸ hn))) := by
+        (h _ (get_mem l n (@length_pmap _ _ p f l h ▸ hn))) := by
   simp only [get_eq_getElem]
   simp [getElem_pmap]
 
 @[simp]
 theorem getElem?_attachWith {xs : List α} {i : Nat} {P : α → Prop} {H : ∀ a ∈ xs, P a} :
-    (xs.attachWith P H)[i]? = xs[i]?.pmap Subtype.mk (fun _ a => H _ (mem_of_getElem? a)) :=
+    (xs.attachWith P H)[i]? = xs[i]?.pmap Subtype.mk (fun _ a => H _ (getElem?_mem a)) :=
   getElem?_pmap ..
 
 @[simp]
 theorem getElem?_attach {xs : List α} {i : Nat} :
-    xs.attach[i]? = xs[i]?.pmap Subtype.mk (fun _ a => mem_of_getElem? a) :=
+    xs.attach[i]? = xs[i]?.pmap Subtype.mk (fun _ a => getElem?_mem a) :=
   getElem?_attachWith
 
 @[simp]
@@ -338,7 +333,6 @@ This is useful when we need to use `attach` to show termination.
 
 Unfortunately this can't be applied by `simp` because of the higher order unification problem,
 and even when rewriting we need to specify the function explicitly.
-See however `foldl_subtype` below.
 -/
 theorem foldl_attach (l : List α) (f : β → α → β) (b : β) :
     l.attach.foldl (fun acc t => f acc t.1) b = l.foldl f b := by
@@ -354,7 +348,6 @@ This is useful when we need to use `attach` to show termination.
 
 Unfortunately this can't be applied by `simp` because of the higher order unification problem,
 and even when rewriting we need to specify the function explicitly.
-See however `foldr_subtype` below.
 -/
 theorem foldr_attach (l : List α) (f : α → β → β) (b : β) :
     l.attach.foldr (fun t acc => f t.1 acc) b = l.foldr f b := by
@@ -459,16 +452,16 @@ theorem pmap_append' {p : α → Prop} (f : ∀ a : α, p a → β) (l₁ l₂ :
   pmap_append f l₁ l₂ _
 
 @[simp] theorem attach_append (xs ys : List α) :
-    (xs ++ ys).attach = xs.attach.map (fun ⟨x, h⟩ => ⟨x, mem_append_left ys h⟩) ++
-      ys.attach.map fun ⟨x, h⟩ => ⟨x, mem_append_right xs h⟩ := by
+    (xs ++ ys).attach = xs.attach.map (fun ⟨x, h⟩ => ⟨x, mem_append_of_mem_left ys h⟩) ++
+      ys.attach.map fun ⟨x, h⟩ => ⟨x, mem_append_of_mem_right xs h⟩ := by
   simp only [attach, attachWith, pmap, map_pmap, pmap_append]
   congr 1 <;>
   exact pmap_congr_left _ fun _ _ _ _ => rfl
 
 @[simp] theorem attachWith_append {P : α → Prop} {xs ys : List α}
     {H : ∀ (a : α), a ∈ xs ++ ys → P a} :
-    (xs ++ ys).attachWith P H = xs.attachWith P (fun a h => H a (mem_append_left ys h)) ++
-      ys.attachWith P (fun a h => H a (mem_append_right xs h)) := by
+    (xs ++ ys).attachWith P H = xs.attachWith P (fun a h => H a (mem_append_of_mem_left ys h)) ++
+      ys.attachWith P (fun a h => H a (mem_append_of_mem_right xs h)) := by
   simp only [attachWith, attach_append, map_pmap, pmap_append]
 
 @[simp] theorem pmap_reverse {P : α → Prop} (f : (a : α) → P a → β) (xs : List α)
@@ -605,15 +598,6 @@ def unattach {α : Type _} {p : α → Prop} (l : List { x // p x }) := l.map (
   | nil => simp
   | cons a l ih => simp [ih, Function.comp_def]
 
-@[simp] theorem getElem?_unattach {p : α → Prop} {l : List { x // p x }} (i : Nat) :
-    l.unattach[i]? = l[i]?.map Subtype.val := by
-  simp [unattach]
-
-@[simp] theorem getElem_unattach
-    {p : α → Prop} {l : List { x // p x }} (i : Nat) (h : i < l.unattach.length) :
-    l.unattach[i] = (l[i]'(by simpa using h)).1 := by
-  simp [unattach]
-
 /-! ### Recognizing higher order functions on subtypes using a function that only depends on the value. -/
 
 /--

src/Init/Data/List/Basic.lean

@@ -231,7 +231,7 @@ theorem ext_get? : ∀ {l₁ l₂ : List α}, (∀ n, l₁.get? n = l₂.get? n)
     injection h0 with aa; simp only [aa, ext_get? fun n => h (n+1)]
 
 /-- Deprecated alias for `ext_get?`. The preferred extensionality theorem is now `ext_getElem?`. -/
-@[deprecated ext_get? (since := "2024-06-07")] abbrev ext := @ext_get?
+@[deprecated (since := "2024-06-07")] abbrev ext := @ext_get?
 
 /-! ### getD -/
 
@@ -666,14 +666,10 @@ def isEmpty : List α → Bool
 /-! ### elem -/
 
 /--
-`O(|l|)`.
-`l.contains a` or `elem a l` is true if there is an element in `l` equal (according to `==`) to `a`.
+`O(|l|)`. `elem a l` or `l.contains a` is true if there is an element in `l` equal to `a`.
 
-* `[1, 4, 2, 3, 3, 7].contains 3 = true`
-* `[1, 4, 2, 3, 3, 7].contains 5 = false`
-
-The preferred simp normal form is `l.contains a`, and when `LawfulBEq α` is available,
-`l.contains a = true ↔ a ∈ l` and `l.contains a = false ↔ a ∉ l`.
+* `elem 3 [1, 4, 2, 3, 3, 7] = true`
+* `elem 5 [1, 4, 2, 3, 3, 7] = false`
 -/
 def elem [BEq α] (a : α) : List α → Bool
   | []    => false
@@ -686,7 +682,7 @@ theorem elem_cons [BEq α] {a : α} :
     (b::bs).elem a = match a == b with | true => true | false => bs.elem a := rfl
 
 /-- `notElem a l` is `!(elem a l)`. -/
-@[deprecated "Use `!(elem a l)` instead."(since := "2024-06-15")]
+@[deprecated (since := "2024-06-15")]
 def notElem [BEq α] (a : α) (as : List α) : Bool :=
   !(as.elem a)
 
@@ -730,13 +726,13 @@ theorem elem_eq_true_of_mem [BEq α] [LawfulBEq α] {a : α} {as : List α} (h :
 instance [BEq α] [LawfulBEq α] (a : α) (as : List α) : Decidable (a ∈ as) :=
   decidable_of_decidable_of_iff (Iff.intro mem_of_elem_eq_true elem_eq_true_of_mem)
 
-theorem mem_append_left {a : α} {as : List α} (bs : List α) : a ∈ as → a ∈ as ++ bs := by
+theorem mem_append_of_mem_left {a : α} {as : List α} (bs : List α) : a ∈ as → a ∈ as ++ bs := by
   intro h
   induction h with
   | head => apply Mem.head
   | tail => apply Mem.tail; assumption
 
-theorem mem_append_right {b : α} {bs : List α} (as : List α) : b ∈ bs → b ∈ as ++ bs := by
+theorem mem_append_of_mem_right {b : α} {bs : List α} (as : List α) : b ∈ bs → b ∈ as ++ bs := by
   intro h
   induction as with
   | nil  => simp [h]
@@ -1431,10 +1427,10 @@ def zipWithAll (f : Option α → Option β → γ) : List α → List β → Li
   | a :: as, [] => (a :: as).map fun a => f (some a) none
   | a :: as, b :: bs => f a b :: zipWithAll f as bs
 
-@[simp] theorem zipWithAll_nil :
+@[simp] theorem zipWithAll_nil_right :
     zipWithAll f as [] = as.map fun a => f (some a) none := by
   cases as <;> rfl
-@[simp] theorem nil_zipWithAll :
+@[simp] theorem zipWithAll_nil_left :
     zipWithAll f [] bs = bs.map fun b => f none (some b) := rfl
 @[simp] theorem zipWithAll_cons_cons :
     zipWithAll f (a :: as) (b :: bs) = f (some a) (some b) :: zipWithAll f as bs := rfl

src/Init/Data/List/BasicAux.lean

@@ -155,8 +155,7 @@ def mapMono (as : List α) (f : α → α) : List α :=
 
 /-! ## Additional lemmas required for bootstrapping `Array`. -/
 
-theorem getElem_append_left {as bs : List α} (h : i < as.length) {h' : i < (as ++ bs).length} :
-    (as ++ bs)[i] = as[i] := by
+theorem getElem_append_left {as bs : List α} (h : i < as.length) {h'} : (as ++ bs)[i] = as[i] := by
   induction as generalizing i with
   | nil => trivial
   | cons a as ih =>

src/Init/Data/List/Control.lean

@@ -256,7 +256,7 @@ theorem findM?_eq_findSomeM? [Monad m] [LawfulMonad m] (p : α → m Bool) (as :
       have : a ∈ as := by
         have ⟨bs, h⟩ := h
         subst h
-        exact mem_append_right _ (Mem.head ..)
+        exact mem_append_of_mem_right _ (Mem.head ..)
       match (← f a this b) with
       | ForInStep.done b  => pure b
       | ForInStep.yield b =>

src/Init/Data/List/Count.lean

@@ -162,10 +162,6 @@ theorem countP_filterMap (p : β → Bool) (f : α → Option β) (l : List α)
 
 @[deprecated countP_flatten (since := "2024-10-14")] abbrev countP_join := @countP_flatten
 
-theorem countP_flatMap (p : β → Bool) (l : List α) (f : α → List β) :
-    countP p (l.flatMap f) = sum (map (countP p ∘ f) l) := by
-  rw [List.flatMap, countP_flatten, map_map]
-
 @[simp] theorem countP_reverse (l : List α) : countP p l.reverse = countP p l := by
   simp [countP_eq_length_filter, filter_reverse]
 
@@ -330,9 +326,6 @@ theorem count_filterMap {α} [BEq β] (b : β) (f : α → Option β) (l : List
   · simp
   · simp
 
-theorem count_flatMap {α} [BEq β] (l : List α) (f : α → List β) (x : β) :
-    count x (l.flatMap f) = sum (map (count x ∘ f) l) := countP_flatMap _ _ _
-
 theorem count_erase (a b : α) :
     ∀ l : List α, count a (l.erase b) = count a l - if b == a then 1 else 0
   | [] => by simp

src/Init/Data/List/FinRange.lean

@@ -1,48 +0,0 @@
-/-
-Copyright (c) 2024 François G. Dorais. All rights reserved.
-Released under Apache 2.0 license as described in the file LICENSE.
-Authors: François G. Dorais
--/
-prelude
-import Init.Data.List.OfFn
-
-namespace List
-
-/-- `finRange n` lists all elements of `Fin n` in order -/
-def finRange (n : Nat) : List (Fin n) := ofFn fun i => i
-
-@[simp] theorem length_finRange (n) : (List.finRange n).length = n := by
-  simp [List.finRange]
-
-@[simp] theorem getElem_finRange (i : Nat) (h : i < (List.finRange n).length) :
-    (finRange n)[i] = Fin.cast (length_finRange n) ⟨i, h⟩ := by
-  simp [List.finRange]
-
-@[simp] theorem finRange_zero : finRange 0 = [] := by simp [finRange, ofFn]
-
-theorem finRange_succ (n) : finRange (n+1) = 0 :: (finRange n).map Fin.succ := by
-  apply List.ext_getElem; simp; intro i; cases i <;> simp
-
-theorem finRange_succ_last (n) :
-    finRange (n+1) = (finRange n).map Fin.castSucc ++ [Fin.last n] := by
-  apply List.ext_getElem
-  · simp
-  · intros
-    simp only [List.finRange, List.getElem_ofFn, getElem_append, length_map, length_ofFn,
-      getElem_map, Fin.castSucc_mk, getElem_singleton]
-    split
-    · rfl
-    · next h => exact Fin.eq_last_of_not_lt h
-
-theorem finRange_reverse (n) : (finRange n).reverse = (finRange n).map Fin.rev := by
-  induction n with
-  | zero => simp
-  | succ n ih =>
-    conv => lhs; rw [finRange_succ_last]
-    conv => rhs; rw [finRange_succ]
-    rw [reverse_append, reverse_cons, reverse_nil, nil_append, singleton_append, ← map_reverse,
-      map_cons, ih, map_map, map_map]
-    congr; funext
-    simp [Fin.rev_succ]
-
-end List

src/Init/Data/List/Lemmas.lean

@@ -83,12 +83,44 @@ open Nat
 @[simp] theorem nil_eq {α} {xs : List α} : [] = xs ↔ xs = [] := by
   cases xs <;> simp
 
+/-! ### cons -/
+
+theorem cons_ne_nil (a : α) (l : List α) : a :: l ≠ [] := nofun
+
+@[simp]
+theorem cons_ne_self (a : α) (l : List α) : a :: l ≠ l := mt (congrArg length) (Nat.succ_ne_self _)
+
+@[simp] theorem ne_cons_self {a : α} {l : List α} : l ≠ a :: l := by
+  rw [ne_eq, eq_comm]
+  simp
+
+theorem head_eq_of_cons_eq (H : h₁ :: t₁ = h₂ :: t₂) : h₁ = h₂ := (cons.inj H).1
+
+theorem tail_eq_of_cons_eq (H : h₁ :: t₁ = h₂ :: t₂) : t₁ = t₂ := (cons.inj H).2
+
+theorem cons_inj_right (a : α) {l l' : List α} : a :: l = a :: l' ↔ l = l' :=
+  ⟨tail_eq_of_cons_eq, congrArg _⟩
+
+@[deprecated (since := "2024-06-15")] abbrev cons_inj := @cons_inj_right
+
+theorem cons_eq_cons {a b : α} {l l' : List α} : a :: l = b :: l' ↔ a = b ∧ l = l' :=
+  List.cons.injEq .. ▸ .rfl
+
+theorem exists_cons_of_ne_nil : ∀ {l : List α}, l ≠ [] → ∃ b L, l = b :: L
+  | c :: l', _ => ⟨c, l', rfl⟩
+
+theorem singleton_inj {α : Type _} {a b : α} : [a] = [b] ↔ a = b := by
+  simp
+
 /-! ### length -/
 
 theorem eq_nil_of_length_eq_zero (_ : length l = 0) : l = [] := match l with | [] => rfl
 
 theorem ne_nil_of_length_eq_add_one (_ : length l = n + 1) : l ≠ [] := fun _ => nomatch l
 
+@[deprecated ne_nil_of_length_eq_add_one (since := "2024-06-16")]
+abbrev ne_nil_of_length_eq_succ := @ne_nil_of_length_eq_add_one
+
 theorem ne_nil_of_length_pos (_ : 0 < length l) : l ≠ [] := fun _ => nomatch l
 
 @[simp] theorem length_eq_zero : length l = 0 ↔ l = [] :=
@@ -124,36 +156,6 @@ theorem length_pos {l : List α} : 0 < length l ↔ l ≠ [] :=
 theorem length_eq_one {l : List α} : length l = 1 ↔ ∃ a, l = [a] :=
   ⟨fun h => match l, h with | [_], _ => ⟨_, rfl⟩, fun ⟨_, h⟩ => by simp [h]⟩
 
-/-! ### cons -/
-
-theorem cons_ne_nil (a : α) (l : List α) : a :: l ≠ [] := nofun
-
-@[simp]
-theorem cons_ne_self (a : α) (l : List α) : a :: l ≠ l := mt (congrArg length) (Nat.succ_ne_self _)
-
-@[simp] theorem ne_cons_self {a : α} {l : List α} : l ≠ a :: l := by
-  rw [ne_eq, eq_comm]
-  simp
-
-theorem head_eq_of_cons_eq (H : h₁ :: t₁ = h₂ :: t₂) : h₁ = h₂ := (cons.inj H).1
-
-theorem tail_eq_of_cons_eq (H : h₁ :: t₁ = h₂ :: t₂) : t₁ = t₂ := (cons.inj H).2
-
-theorem cons_inj_right (a : α) {l l' : List α} : a :: l = a :: l' ↔ l = l' :=
-  ⟨tail_eq_of_cons_eq, congrArg _⟩
-
-theorem cons_eq_cons {a b : α} {l l' : List α} : a :: l = b :: l' ↔ a = b ∧ l = l' :=
-  List.cons.injEq .. ▸ .rfl
-
-theorem exists_cons_of_ne_nil : ∀ {l : List α}, l ≠ [] → ∃ b L, l = b :: L
-  | c :: l', _ => ⟨c, l', rfl⟩
-
-theorem ne_nil_iff_exists_cons {l : List α} : l ≠ [] ↔ ∃ b L, l = b :: L :=
-  ⟨exists_cons_of_ne_nil, fun ⟨_, _, eq⟩ => eq.symm ▸ cons_ne_nil _ _⟩
-
-theorem singleton_inj {α : Type _} {a b : α} : [a] = [b] ↔ a = b := by
-  simp
-
 /-! ## L[i] and L[i]? -/
 
 /-! ### `get` and `get?`.
@@ -161,29 +163,57 @@ theorem singleton_inj {α : Type _} {a b : α} : [a] = [b] ↔ a = b := by
 We simplify `l.get i` to `l[i.1]'i.2` and `l.get? i` to `l[i]?`.
 -/
 
-@[simp] theorem get_eq_getElem (l : List α) (i : Fin l.length) : l.get i = l[i.1]'i.2 := rfl
+theorem get_cons_zero : get (a::l) (0 : Fin (l.length + 1)) = a := rfl
 
-theorem get?_eq_none : ∀ {l : List α} {n}, length l ≤ n → l.get? n = none
+theorem get_cons_succ {as : List α} {h : i + 1 < (a :: as).length} :
+  (a :: as).get ⟨i+1, h⟩ = as.get ⟨i, Nat.lt_of_succ_lt_succ h⟩ := rfl
+
+theorem get_cons_succ' {as : List α} {i : Fin as.length} :
+  (a :: as).get i.succ = as.get i := rfl
+
+@[deprecated (since := "2024-07-09")]
+theorem get_cons_cons_one : (a₁ :: a₂ :: as).get (1 : Fin (as.length + 2)) = a₂ := rfl
+
+theorem get_mk_zero : ∀ {l : List α} (h : 0 < l.length), l.get ⟨0, h⟩ = l.head (length_pos.mp h)
+  | _::_, _ => rfl
+
+theorem get?_zero (l : List α) : l.get? 0 = l.head? := by cases l <;> rfl
+
+theorem get?_len_le : ∀ {l : List α} {n}, length l ≤ n → l.get? n = none
   | [], _, _ => rfl
-  | _ :: l, _+1, h => get?_eq_none (l := l) <| Nat.le_of_succ_le_succ h
+  | _ :: l, _+1, h => get?_len_le (l := l) <| Nat.le_of_succ_le_succ h
 
 theorem get?_eq_get : ∀ {l : List α} {n} (h : n < l.length), l.get? n = some (get l ⟨n, h⟩)
   | _ :: _, 0, _ => rfl
   | _ :: l, _+1, _ => get?_eq_get (l := l) _
 
-theorem get?_eq_some_iff : l.get? n = some a ↔ ∃ h, get l ⟨n, h⟩ = a :=
+theorem get?_eq_some : l.get? n = some a ↔ ∃ h, get l ⟨n, h⟩ = a :=
   ⟨fun e =>
-    have : n < length l := Nat.gt_of_not_le fun hn => by cases get?_eq_none hn ▸ e
+    have : n < length l := Nat.gt_of_not_le fun hn => by cases get?_len_le hn ▸ e
     ⟨this, by rwa [get?_eq_get this, Option.some.injEq] at e⟩,
   fun ⟨_, e⟩ => e ▸ get?_eq_get _⟩
 
-theorem get?_eq_none_iff : l.get? n = none ↔ length l ≤ n :=
-  ⟨fun e => Nat.ge_of_not_lt (fun h' => by cases e ▸ get?_eq_some_iff.2 ⟨h', rfl⟩), get?_eq_none⟩
+theorem get?_eq_none : l.get? n = none ↔ length l ≤ n :=
+  ⟨fun e => Nat.ge_of_not_lt (fun h' => by cases e ▸ get?_eq_some.2 ⟨h', rfl⟩), get?_len_le⟩
 
 @[simp] theorem get?_eq_getElem? (l : List α) (i : Nat) : l.get? i = l[i]? := by
-  simp only [getElem?_def]; split
+  simp only [getElem?, decidableGetElem?]; split
   · exact (get?_eq_get ‹_›)
-  · exact (get?_eq_none_iff.2 <| Nat.not_lt.1 ‹_›)
+  · exact (get?_eq_none.2 <| Nat.not_lt.1 ‹_›)
+
+@[simp] theorem get_eq_getElem (l : List α) (i : Fin l.length) : l.get i = l[i.1]'i.2 := rfl
+
+theorem getElem?_eq_some {l : List α} : l[i]? = some a ↔ ∃ h : i < l.length, l[i]'h = a := by
+  simpa using get?_eq_some
+
+/--
+If one has `l.get i` in an expression (with `i : Fin l.length`) and `h : l = l'`,
+`rw [h]` will give a "motive it not type correct" error, as it cannot rewrite the
+`i : Fin l.length` to `Fin l'.length` directly. The theorem `get_of_eq` can be used to make
+such a rewrite, with `rw [get_of_eq h]`.
+-/
+theorem get_of_eq {l l' : List α} (h : l = l') (i : Fin l.length) :
+    get l i = get l' ⟨i, h ▸ i.2⟩ := by cases h; rfl
 
 /-! ### getD
 
@@ -194,54 +224,71 @@ Because of this, there is only minimal API for `getD`.
 @[simp] theorem getD_eq_getElem?_getD (l) (n) (a : α) : getD l n a = (l[n]?).getD a := by
   simp [getD]
 
+@[deprecated getD_eq_getElem?_getD (since := "2024-06-12")]
+theorem getD_eq_get? : ∀ l n (a : α), getD l n a = (get? l n).getD a := by simp
+
 /-! ### get!
 
 We simplify `l.get! n` to `l[n]!`.
 -/
 
+theorem get!_of_get? [Inhabited α] : ∀ {l : List α} {n}, get? l n = some a → get! l n = a
+  | _a::_, 0, rfl => rfl
+  | _::l, _+1, e => get!_of_get? (l := l) e
+
 theorem get!_eq_getD [Inhabited α] : ∀ (l : List α) n, l.get! n = l.getD n default
   | [], _      => rfl
   | _a::_, 0   => rfl
   | _a::l, n+1 => get!_eq_getD l n
 
+theorem get!_len_le [Inhabited α] : ∀ {l : List α} {n}, length l ≤ n → l.get! n = (default : α)
+  | [], _, _ => rfl
+  | _ :: l, _+1, h => get!_len_le (l := l) <| Nat.le_of_succ_le_succ h
+
 @[simp] theorem get!_eq_getElem! [Inhabited α] (l : List α) (n) : l.get! n = l[n]! := by
   simp [get!_eq_getD]
   rfl
 
-/-! ### getElem!
+/-! ### getElem! -/
 
-We simplify `l[n]!` to `(l[n]?).getD default`.
--/
+@[simp] theorem getElem!_nil [Inhabited α] {n : Nat} : ([] : List α)[n]! = default := rfl
 
-@[simp] theorem getElem!_eq_getElem?_getD [Inhabited α] (l : List α) (n : Nat) :
-    l[n]! = (l[n]?).getD (default : α) := by
-  simp only [getElem!_def]
-  split <;> simp_all
+@[simp] theorem getElem!_cons_zero [Inhabited α] {l : List α} : (a::l)[0]! = a := by
+  rw [getElem!_pos] <;> simp
+
+@[simp] theorem getElem!_cons_succ [Inhabited α] {l : List α} : (a::l)[n+1]! = l[n]! := by
+  by_cases h : n < l.length
+  · rw [getElem!_pos, getElem!_pos] <;> simp_all [Nat.succ_lt_succ_iff]
+  · rw [getElem!_neg, getElem!_neg] <;> simp_all [Nat.succ_lt_succ_iff]
 
 /-! ### getElem? and getElem -/
 
+@[simp] theorem getElem?_eq_getElem {l : List α} {n} (h : n < l.length) : l[n]? = some l[n] := by
+  simp only [getElem?_def, h, ↓reduceDIte]
+
+theorem getElem?_eq_some_iff {l : List α} : l[n]? = some a ↔ ∃ h : n < l.length, l[n] = a := by
+  simp only [← get?_eq_getElem?, get?_eq_some, get_eq_getElem]
+
+theorem some_eq_getElem?_iff {l : List α} : some a = l[n]? ↔ ∃ h : n < l.length, l[n] = a := by
+  rw [eq_comm, getElem?_eq_some_iff]
+
 @[simp] theorem getElem?_eq_none_iff : l[n]? = none ↔ length l ≤ n := by
-  simp only [← get?_eq_getElem?, get?_eq_none_iff]
+  simp only [← get?_eq_getElem?, get?_eq_none]
 
 @[simp] theorem none_eq_getElem?_iff {l : List α} {n : Nat} : none = l[n]? ↔ length l ≤ n := by
   simp [eq_comm (a := none)]
 
 theorem getElem?_eq_none (h : length l ≤ n) : l[n]? = none := getElem?_eq_none_iff.mpr h
 
-@[simp] theorem getElem?_eq_getElem {l : List α} {n} (h : n < l.length) : l[n]? = some l[n] :=
-  getElem?_pos ..
+theorem getElem?_eq (l : List α) (i : Nat) :
+    l[i]? = if h : i < l.length then some l[i] else none := by
+  split <;> simp_all
 
-theorem getElem?_eq_some_iff {l : List α} : l[n]? = some a ↔ ∃ h : n < l.length, l[n] = a := by
-  simp only [← get?_eq_getElem?, get?_eq_some_iff, get_eq_getElem]
-
-theorem some_eq_getElem?_iff {l : List α} : some a = l[n]? ↔ ∃ h : n < l.length, l[n] = a := by
-  rw [eq_comm, getElem?_eq_some_iff]
-
-@[simp] theorem some_getElem_eq_getElem?_iff (xs : List α) (i : Nat) (h : i < xs.length) :
+@[simp] theorem some_getElem_eq_getElem?_iff {α} (xs : List α) (i : Nat) (h : i < xs.length) :
     (some xs[i] = xs[i]?) ↔ True := by
   simp [h]
 
-@[simp] theorem getElem?_eq_some_getElem_iff (xs : List α) (i : Nat) (h : i < xs.length) :
+@[simp] theorem getElem?_eq_some_getElem_iff {α} (xs : List α) (i : Nat) (h : i < xs.length) :
     (xs[i]? = some xs[i]) ↔ True := by
   simp [h]
 
@@ -253,12 +300,10 @@ theorem getElem_eq_getElem?_get (l : List α) (i : Nat) (h : i < l.length) :
     l[i] = l[i]?.get (by simp [getElem?_eq_getElem, h]) := by
   simp [getElem_eq_iff]
 
-@[simp] theorem getElem?_nil {n : Nat} : ([] : List α)[n]? = none := rfl
+@[deprecated getElem_eq_getElem?_get (since := "2024-09-04")] abbrev getElem_eq_getElem? :=
+  @getElem_eq_getElem?_get
 
-theorem getElem_cons {l : List α} (w : i < (a :: l).length) :
-    (a :: l)[i] =
-      if h : i = 0 then a else l[i-1]'(match i, h with | i+1, _ => succ_lt_succ_iff.mp w) := by
-  cases i <;> simp
+@[simp] theorem getElem?_nil {n : Nat} : ([] : List α)[n]? = none := rfl
 
 theorem getElem?_cons_zero {l : List α} : (a::l)[0]? = some a := by simp
 
@@ -269,12 +314,10 @@ theorem getElem?_cons_zero {l : List α} : (a::l)[0]? = some a := by simp
 theorem getElem?_cons : (a :: l)[i]? = if i = 0 then some a else l[i-1]? := by
   cases i <;> simp
 
-@[simp] theorem getElem_singleton (a : α) (h : i < 1) : [a][i] = a :=
-  match i, h with
-  | 0, _ => rfl
-
-theorem getElem?_singleton (a : α) (i : Nat) : [a][i]? = if i = 0 then some a else none := by
-  simp [getElem?_cons]
+theorem getElem?_len_le : ∀ {l : List α} {n}, length l ≤ n → l[n]? = none
+  | [], _, _ => rfl
+  | _ :: l, _+1, h => by
+    rw [getElem?_cons_succ, getElem?_len_le (l := l) <| Nat.le_of_succ_le_succ h]
 
 /--
 If one has `l[i]` in an expression and `h : l = l'`,
@@ -285,10 +328,24 @@ such a rewrite, with `rw [getElem_of_eq h]`.
 theorem getElem_of_eq {l l' : List α} (h : l = l') {i : Nat} (w : i < l.length) :
     l[i] = l'[i]'(h ▸ w) := by cases h; rfl
 
+@[simp] theorem getElem_singleton (a : α) (h : i < 1) : [a][i] = a :=
+  match i, h with
+  | 0, _ => rfl
+
+@[deprecated getElem_singleton (since := "2024-06-12")]
+theorem get_singleton (a : α) (n : Fin 1) : get [a] n = a := by simp
+
 theorem getElem_zero {l : List α} (h : 0 < l.length) : l[0] = l.head (length_pos.mp h) :=
   match l, h with
   | _ :: _, _ => rfl
 
+theorem getElem!_of_getElem? [Inhabited α] : ∀ {l : List α} {n : Nat}, l[n]? = some a → l[n]! = a
+  | _a::_, 0, _ => by
+    rw [getElem!_pos] <;> simp_all
+  | _::l, _+1, e => by
+    simp at e
+    simp_all [getElem!_of_getElem? (l := l) e]
+
 @[ext] theorem ext_getElem? {l₁ l₂ : List α} (h : ∀ n : Nat, l₁[n]? = l₂[n]?) : l₁ = l₂ :=
   ext_get? fun n => by simp_all
 
@@ -299,7 +356,11 @@ theorem ext_getElem {l₁ l₂ : List α} (hl : length l₁ = length l₂)
       simp_all [getElem?_eq_getElem]
     else by
       have h₁ := Nat.le_of_not_lt h₁
-      rw [getElem?_eq_none h₁, getElem?_eq_none]; rwa [← hl]
+      rw [getElem?_len_le h₁, getElem?_len_le]; rwa [← hl]
+
+theorem ext_get {l₁ l₂ : List α} (hl : length l₁ = length l₂)
+    (h : ∀ n h₁ h₂, get l₁ ⟨n, h₁⟩ = get l₂ ⟨n, h₂⟩) : l₁ = l₂ :=
+  ext_getElem hl (by simp_all)
 
 @[simp] theorem getElem_concat_length : ∀ (l : List α) (a : α) (i) (_ : i = l.length) (w), (l ++ [a])[i]'w = a
   | [], a, _, h, _ => by subst h; simp
@@ -308,6 +369,20 @@ theorem ext_getElem {l₁ l₂ : List α} (hl : length l₁ = length l₂)
 theorem getElem?_concat_length (l : List α) (a : α) : (l ++ [a])[l.length]? = some a := by
   simp
 
+@[deprecated getElem?_concat_length (since := "2024-06-12")]
+theorem get?_concat_length (l : List α) (a : α) : (l ++ [a]).get? l.length = some a := by simp
+
+@[simp] theorem isSome_getElem? {l : List α} {n : Nat} : l[n]?.isSome ↔ n < l.length := by
+  by_cases h : n < l.length
+  · simp_all
+  · simp [h]
+    simp_all
+
+@[simp] theorem isNone_getElem? {l : List α} {n : Nat} : l[n]?.isNone ↔ l.length ≤ n := by
+  by_cases h : n < l.length
+  · simp_all
+  · simp [h]
+
 /-! ### mem -/
 
 @[simp] theorem not_mem_nil (a : α) : ¬ a ∈ [] := nofun
@@ -319,9 +394,9 @@ theorem getElem?_concat_length (l : List α) (a : α) : (l ++ [a])[l.length]? =
 theorem mem_cons_self (a : α) (l : List α) : a ∈ a :: l := .head ..
 
 theorem mem_concat_self (xs : List α) (a : α) : a ∈ xs ++ [a] :=
-  mem_append_right xs (mem_cons_self a _)
+  mem_append_of_mem_right xs (mem_cons_self a _)
 
-theorem mem_append_cons_self : a ∈ xs ++ a :: ys := mem_append_right _ (mem_cons_self _ _)
+theorem mem_append_cons_self : a ∈ xs ++ a :: ys := mem_append_of_mem_right _ (mem_cons_self _ _)
 
 theorem eq_append_cons_of_mem {a : α} {xs : List α} (h : a ∈ xs) :
     ∃ as bs, xs = as ++ a :: bs ∧ a ∉ as := by
@@ -418,19 +493,38 @@ theorem getElem_of_mem : ∀ {a} {l : List α}, a ∈ l → ∃ (n : Nat) (h : n
   | _, _ :: _, .head .. => ⟨0, Nat.succ_pos _, rfl⟩
   | _, _ :: _, .tail _ m => let ⟨n, h, e⟩ := getElem_of_mem m; ⟨n+1, Nat.succ_lt_succ h, e⟩
 
-theorem getElem?_of_mem {a} {l : List α} (h : a ∈ l) : ∃ n : Nat, l[n]? = some a := by
-  let ⟨n, _, e⟩ := getElem_of_mem h
-  exact ⟨n, e ▸ getElem?_eq_getElem _⟩
+theorem get_of_mem {a} {l : List α} (h : a ∈ l) : ∃ n, get l n = a := by
+  obtain ⟨n, h, e⟩ := getElem_of_mem h
+  exact ⟨⟨n, h⟩, e⟩
 
-theorem mem_of_getElem? {l : List α} {n : Nat} {a : α} (e : l[n]? = some a) : a ∈ l :=
+theorem getElem?_of_mem {a} {l : List α} (h : a ∈ l) : ∃ n : Nat, l[n]? = some a :=
+  let ⟨n, _, e⟩ := getElem_of_mem h; ⟨n, e ▸ getElem?_eq_getElem _⟩
+
+theorem get?_of_mem {a} {l : List α} (h : a ∈ l) : ∃ n, l.get? n = some a :=
+  let ⟨⟨n, _⟩, e⟩ := get_of_mem h; ⟨n, e ▸ get?_eq_get _⟩
+
+theorem get_mem : ∀ (l : List α) n h, get l ⟨n, h⟩ ∈ l
+  | _ :: _, 0, _ => .head ..
+  | _ :: l, _+1, _ => .tail _ (get_mem l ..)
+
+theorem getElem?_mem {l : List α} {n : Nat} {a : α} (e : l[n]? = some a) : a ∈ l :=
   let ⟨_, e⟩ := getElem?_eq_some_iff.1 e; e ▸ getElem_mem ..
 
+theorem get?_mem {l : List α} {n a} (e : l.get? n = some a) : a ∈ l :=
+  let ⟨_, e⟩ := get?_eq_some.1 e; e ▸ get_mem ..
+
 theorem mem_iff_getElem {a} {l : List α} : a ∈ l ↔ ∃ (n : Nat) (h : n < l.length), l[n]'h = a :=
   ⟨getElem_of_mem, fun ⟨_, _, e⟩ => e ▸ getElem_mem ..⟩
 
+theorem mem_iff_get {a} {l : List α} : a ∈ l ↔ ∃ n, get l n = a :=
+  ⟨get_of_mem, fun ⟨_, e⟩ => e ▸ get_mem ..⟩
+
 theorem mem_iff_getElem? {a} {l : List α} : a ∈ l ↔ ∃ n : Nat, l[n]? = some a := by
   simp [getElem?_eq_some_iff, mem_iff_getElem]
 
+theorem mem_iff_get? {a} {l : List α} : a ∈ l ↔ ∃ n, l.get? n = some a := by
+  simp [getElem?_eq_some_iff, Fin.exists_iff, mem_iff_get]
+
 theorem forall_getElem {l : List α} {p : α → Prop} :
     (∀ (n : Nat) h, p (l[n]'h)) ↔ ∀ a, a ∈ l → p a := by
   induction l with
@@ -451,10 +545,6 @@ theorem forall_getElem {l : List α} {p : α → Prop} :
         simp only [getElem_cons_succ]
         exact getElem_mem (lt_of_succ_lt_succ h)
 
-@[simp] theorem elem_eq_contains [BEq α] {a : α} {l : List α} :
-    elem a l = l.contains a := by
-  simp [contains]
-
 @[simp] theorem decide_mem_cons [BEq α] [LawfulBEq α] {l : List α} :
     decide (y ∈ a :: l) = (y == a || decide (y ∈ l)) := by
   cases h : y == a <;> simp_all
@@ -462,27 +552,16 @@ theorem forall_getElem {l : List α} {p : α → Prop} :
 theorem elem_iff [BEq α] [LawfulBEq α] {a : α} {as : List α} :
     elem a as = true ↔ a ∈ as := ⟨mem_of_elem_eq_true, elem_eq_true_of_mem⟩
 
-theorem contains_iff [BEq α] [LawfulBEq α] {a : α} {as : List α} :
-    as.contains a = true ↔ a ∈ as := ⟨mem_of_elem_eq_true, elem_eq_true_of_mem⟩
-
-theorem elem_eq_mem [BEq α] [LawfulBEq α] (a : α) (as : List α) :
+@[simp] theorem elem_eq_mem [BEq α] [LawfulBEq α] (a : α) (as : List α) :
     elem a as = decide (a ∈ as) := by rw [Bool.eq_iff_iff, elem_iff, decide_eq_true_iff]
 
-@[simp] theorem contains_eq_mem [BEq α] [LawfulBEq α] (a : α) (as : List α) :
-    as.contains a = decide (a ∈ as) := by rw [Bool.eq_iff_iff, elem_iff, decide_eq_true_iff]
-
-@[simp] theorem contains_cons [BEq α] {a : α} {b : α} {l : List α} :
-    (a :: l).contains b = (b == a || l.contains b) := by
-  simp only [contains, elem_cons]
-  split <;> simp_all
-
 /-! ### `isEmpty` -/
 
 theorem isEmpty_iff {l : List α} : l.isEmpty ↔ l = [] := by
   cases l <;> simp
 
 theorem isEmpty_eq_false_iff_exists_mem {xs : List α} :
-    xs.isEmpty = false ↔ ∃ x, x ∈ xs := by
+    (List.isEmpty xs = false) ↔ ∃ x, x ∈ xs := by
   cases xs <;> simp
 
 theorem isEmpty_iff_length_eq_zero {l : List α} : l.isEmpty ↔ l.length = 0 := by
@@ -496,6 +575,18 @@ theorem isEmpty_iff_length_eq_zero {l : List α} : l.isEmpty ↔ l.length = 0 :=
 
 /-! ### any / all -/
 
+theorem any_beq [BEq α] [LawfulBEq α] {l : List α} : (l.any fun x => a == x) ↔ a ∈ l := by
+  induction l <;> simp_all
+
+theorem any_beq' [BEq α] [LawfulBEq α] {l : List α} : (l.any fun x => x == a) ↔ a ∈ l := by
+  induction l <;> simp_all [eq_comm (a := a)]
+
+theorem all_bne [BEq α] [LawfulBEq α] {l : List α} : (l.all fun x => a != x) ↔ a ∉ l := by
+  induction l <;> simp_all
+
+theorem all_bne' [BEq α] [LawfulBEq α] {l : List α} : (l.all fun x => x != a) ↔ a ∉ l := by
+  induction l <;> simp_all [eq_comm (a := a)]
+
 theorem any_eq {l : List α} : l.any p = decide (∃ x, x ∈ l ∧ p x) := by induction l <;> simp [*]
 
 theorem all_eq {l : List α} : l.all p = decide (∀ x, x ∈ l → p x) := by induction l <;> simp [*]
@@ -520,22 +611,6 @@ theorem decide_forall_mem {l : List α} {p : α → Prop} [DecidablePred p] :
 @[simp] theorem all_eq_false {l : List α} : l.all p = false ↔ ∃ x, x ∈ l ∧ ¬p x := by
   simp [all_eq]
 
-theorem any_beq [BEq α] {l : List α} {a : α} : (l.any fun x => a == x) = l.contains a := by
-  induction l <;> simp_all [contains_cons]
-
-/-- Variant of `any_beq` with `==` reversed. -/
-theorem any_beq' [BEq α] [PartialEquivBEq α] {l : List α} :
-    (l.any fun x => x == a) = l.contains a := by
-  simp only [BEq.comm, any_beq]
-
-theorem all_bne [BEq α] {l : List α} : (l.all fun x => a != x) = !l.contains a := by
-  induction l <;> simp_all [bne]
-
-/-- Variant of `all_bne` with `!=` reversed. -/
-theorem all_bne' [BEq α] [PartialEquivBEq α] {l : List α} :
-    (l.all fun x => x != a) = !l.contains a := by
-  simp only [bne_comm, all_bne]
-
 /-! ### set -/
 
 -- As `List.set` is defined in `Init.Prelude`, we write the basic simplification lemmas here.
@@ -553,10 +628,19 @@ theorem all_bne' [BEq α] [PartialEquivBEq α] {l : List α} :
   | _ :: _, 0 => by simp
   | _ :: l, i + 1 => by simp [getElem_set_self]
 
+@[deprecated getElem_set_self (since := "2024-09-04")] abbrev getElem_set_eq := @getElem_set_self
+
+@[deprecated getElem_set_self (since := "2024-06-12")]
+theorem get_set_eq {l : List α} {i : Nat} {a : α} (h : i < (l.set i a).length) :
+    (l.set i a).get ⟨i, h⟩ = a := by
+  simp
+
 @[simp] theorem getElem?_set_self {l : List α} {i : Nat} {a : α} (h : i < l.length) :
     (l.set i a)[i]? = some a := by
   simp_all [getElem?_eq_some_iff]
 
+@[deprecated getElem?_set_self (since := "2024-09-04")] abbrev getElem?_set_eq := @getElem?_set_self
+
 /-- This differs from `getElem?_set_self` by monadically mapping `Function.const _ a` over the `Option`
 returned by `l[i]?`. -/
 theorem getElem?_set_self' {l : List α} {i : Nat} {a : α} :
@@ -578,6 +662,12 @@ theorem getElem?_set_self' {l : List α} {i : Nat} {a : α} :
     have g : i ≠ j := h ∘ congrArg (· + 1)
     simp [getElem_set_ne g]
 
+@[deprecated getElem_set_ne (since := "2024-06-12")]
+theorem get_set_ne {l : List α} {i j : Nat} (h : i ≠ j) {a : α}
+    (hj : j < (l.set i a).length) :
+    (l.set i a).get ⟨j, hj⟩ = l.get ⟨j, by simp at hj; exact hj⟩ := by
+  simp [h]
+
 @[simp] theorem getElem?_set_ne {l : List α} {i j : Nat} (h : i ≠ j) {a : α}  :
     (l.set i a)[j]? = l[j]? := by
   by_cases hj : j < (l.set i a).length
@@ -592,6 +682,11 @@ theorem getElem_set {l : List α} {m n} {a} (h) :
   else
     simp [h]
 
+@[deprecated getElem_set (since := "2024-06-12")]
+theorem get_set {l : List α} {m n} {a : α} (h) :
+    (set l m a).get ⟨n, h⟩ = if m = n then a else l.get ⟨n, length_set .. ▸ h⟩ := by
+  simp [getElem_set]
+
 theorem getElem?_set {l : List α} {i j : Nat} {a : α} :
     (l.set i a)[j]? = if i = j then if i < l.length then some a else none else l[j]? := by
   if h : i = j then
@@ -611,14 +706,6 @@ theorem getElem?_set' {l : List α} {i j : Nat} {a : α} :
   · simp only [getElem?_set_self', Option.map_eq_map, ↓reduceIte, *]
   · simp only [ne_eq, not_false_eq_true, getElem?_set_ne, ↓reduceIte, *]
 
-@[simp] theorem set_getElem_self {as : List α} {i : Nat} (h : i < as.length) :
-    as.set i as[i] = as := by
-  apply ext_getElem
-  · simp
-  · intro n h₁ h₂
-    rw [getElem_set]
-    split <;> simp_all
-
 theorem set_eq_of_length_le {l : List α} {n : Nat} (h : l.length ≤ n) {a : α} :
     l.set n a = l := by
   induction l generalizing n with
@@ -633,6 +720,8 @@ theorem set_eq_of_length_le {l : List α} {n : Nat} (h : l.length ≤ n) {a : α
 @[simp] theorem set_eq_nil_iff {l : List α} (n : Nat) (a : α) : l.set n a = [] ↔ l = [] := by
   cases l <;> cases n <;> simp [set]
 
+@[deprecated set_eq_nil_iff (since := "2024-09-05")] abbrev set_eq_nil := @set_eq_nil_iff
+
 theorem set_comm (a b : α) : ∀ {n m : Nat} (l : List α), n ≠ m →
     (l.set n a).set m b = (l.set m b).set n a
   | _, _, [], _ => by simp
@@ -698,24 +787,6 @@ theorem mem_or_eq_of_mem_set : ∀ {l : List α} {n : Nat} {a b : α}, a ∈ l.s
     · intro a
       simp
 
-@[simp] theorem beq_nil_iff [BEq α] {l : List α} : (l == []) = l.isEmpty := by
-  cases l <;> rfl
-
-@[simp] theorem nil_beq_iff [BEq α] {l : List α} : ([] == l) = l.isEmpty := by
-  cases l <;> rfl
-
-@[simp] theorem cons_beq_cons [BEq α] {a b : α} {l₁ l₂ : List α} :
-    (a :: l₁ == b :: l₂) = (a == b && l₁ == l₂) := rfl
-
-theorem length_eq_of_beq [BEq α] {l₁ l₂ : List α} (h : l₁ == l₂) : l₁.length = l₂.length :=
-  match l₁, l₂ with
-  | [], [] => rfl
-  | [], _ :: _ => by simp [beq_nil_iff] at h
-  | _ :: _, [] => by simp [nil_beq_iff] at h
-  | a :: l₁, b :: l₂ => by
-    simp at h
-    simpa [Nat.add_one_inj]using length_eq_of_beq h.2
-
 /-! ### Lexicographic ordering -/
 
 protected theorem lt_irrefl [LT α] (lt_irrefl : ∀ x : α, ¬x < x) (l : List α) : ¬l < l := by
@@ -781,12 +852,6 @@ theorem foldr_eq_foldrM (f : α → β → β) (b) (l : List α) :
     l.foldr f b = l.foldrM (m := Id) f b := by
   induction l <;> simp [*, foldr]
 
-@[simp] theorem id_run_foldlM (f : β → α → Id β) (b) (l : List α) :
-    Id.run (l.foldlM f b) = l.foldl f b := (foldl_eq_foldlM f b l).symm
-
-@[simp] theorem id_run_foldrM (f : α → β → Id β) (b) (l : List α) :
-    Id.run (l.foldrM f b) = l.foldr f b := (foldr_eq_foldrM f b l).symm
-
 /-! ### foldl and foldr -/
 
 @[simp] theorem foldr_cons_eq_append (l : List α) : l.foldr cons l' = l ++ l' := by
@@ -971,7 +1036,7 @@ theorem getLast_eq_getElem : ∀ (l : List α) (h : l ≠ []),
   | _ :: _ :: _, _ => by
     simp [getLast, get, Nat.succ_sub_succ, getLast_eq_getElem]
 
-theorem getElem_length_sub_one_eq_getLast (l : List α) (h : l.length - 1 < l.length) :
+theorem getElem_length_sub_one_eq_getLast (l : List α) (h) :
     l[l.length - 1] = getLast l (by cases l; simp at h; simp) := by
   rw [← getLast_eq_getElem]
 
@@ -1099,8 +1164,7 @@ theorem head_eq_getElem (l : List α) (h : l ≠ []) : head l h = l[0]'(length_p
   | nil => simp at h
   | cons _ _ => simp
 
-theorem getElem_zero_eq_head (l : List α) (h : 0 < l.length) :
-    l[0] = head l (by simpa [length_pos] using h) := by
+theorem getElem_zero_eq_head (l : List α) (h) : l[0] = head l (by simpa [length_pos] using h) := by
   cases l with
   | nil => simp at h
   | cons _ _ => simp
@@ -1692,7 +1756,7 @@ theorem filterMap_eq_cons_iff {l} {b} {bs} :
 @[simp] theorem cons_append_fun (a : α) (as : List α) :
     (fun bs => ((a :: as) ++ bs)) = fun bs => a :: (as ++ bs) := rfl
 
-theorem getElem_append {l₁ l₂ : List α} (n : Nat) (h : n < (l₁ ++ l₂).length) :
+theorem getElem_append {l₁ l₂ : List α} (n : Nat) (h) :
     (l₁ ++ l₂)[n] = if h' : n < l₁.length then l₁[n] else l₂[n - l₁.length]'(by simp at h h'; exact Nat.sub_lt_left_of_lt_add h' h) := by
   split <;> rename_i h'
   · rw [getElem_append_left h']
@@ -1732,7 +1796,7 @@ theorem getElem_append_right' (l₁ : List α) {l₂ : List α} {n : Nat} (hn :
     l₂[n] = (l₁ ++ l₂)[n + l₁.length]'(by simpa [Nat.add_comm] using Nat.add_lt_add_left hn _) := by
   rw [getElem_append_right] <;> simp [*, le_add_left]
 
-@[deprecated "Deprecated without replacement." (since := "2024-06-12")]
+@[deprecated (since := "2024-06-12")]
 theorem get_append_right_aux {l₁ l₂ : List α} {n : Nat}
   (h₁ : l₁.length ≤ n) (h₂ : n < (l₁ ++ l₂).length) : n - l₁.length < l₂.length := by
   rw [length_append] at h₂
@@ -1749,7 +1813,7 @@ theorem getElem_of_append {l : List α} (eq : l = l₁ ++ a :: l₂) (h : l₁.l
   rw [← getElem?_eq_getElem, eq, getElem?_append_right (h ▸ Nat.le_refl _), h]
   simp
 
-@[deprecated "Deprecated without replacement." (since := "2024-06-12")]
+@[deprecated (since := "2024-06-12")]
 theorem get_of_append_proof {l : List α}
     (eq : l = l₁ ++ a :: l₂) (h : l₁.length = n) : n < length l := eq ▸ h ▸ by simp_arith
 
@@ -1933,8 +1997,11 @@ theorem not_mem_append {a : α} {s t : List α} (h₁ : a ∉ s) (h₂ : a ∉ t
 theorem mem_append_eq (a : α) (s t : List α) : (a ∈ s ++ t) = (a ∈ s ∨ a ∈ t) :=
   propext mem_append
 
-@[deprecated mem_append_left (since := "2024-11-20")] abbrev mem_append_of_mem_left := @mem_append_left
-@[deprecated mem_append_right (since := "2024-11-20")] abbrev mem_append_of_mem_right := @mem_append_right
+theorem mem_append_left {a : α} {l₁ : List α} (l₂ : List α) (h : a ∈ l₁) : a ∈ l₁ ++ l₂ :=
+  mem_append.2 (Or.inl h)
+
+theorem mem_append_right {a : α} (l₁ : List α) {l₂ : List α} (h : a ∈ l₂) : a ∈ l₁ ++ l₂ :=
+  mem_append.2 (Or.inr h)
 
 theorem mem_iff_append {a : α} {l : List α} : a ∈ l ↔ ∃ s t : List α, l = s ++ a :: t :=
   ⟨append_of_mem, fun ⟨s, t, e⟩ => e ▸ by simp⟩
@@ -2234,11 +2301,6 @@ theorem flatMap_def (l : List α) (f : α → List β) : l.flatMap f = flatten (
 
 @[simp] theorem flatMap_id (l : List (List α)) : List.flatMap l id = l.flatten := by simp [flatMap_def]
 
-@[simp]
-theorem length_flatMap (l : List α) (f : α → List β) :
-    length (l.flatMap f) = sum (map (length ∘ f) l) := by
-  rw [List.flatMap, length_flatten, map_map]
-
 @[simp] theorem mem_flatMap {f : α → List β} {b} {l : List α} : b ∈ l.flatMap f ↔ ∃ a, a ∈ l ∧ b ∈ f a := by
   simp [flatMap_def, mem_flatten]
   exact ⟨fun ⟨_, ⟨a, h₁, rfl⟩, h₂⟩ => ⟨a, h₁, h₂⟩, fun ⟨a, h₁, h₂⟩ => ⟨_, ⟨a, h₁, rfl⟩, h₂⟩⟩
@@ -2353,7 +2415,7 @@ theorem forall_mem_replicate {p : α → Prop} {a : α} {n} :
 
 @[simp] theorem getElem_replicate (a : α) {n : Nat} {m} (h : m < (replicate n a).length) :
     (replicate n a)[m] = a :=
-  eq_of_mem_replicate (getElem_mem _)
+  eq_of_mem_replicate (get_mem _ _ _)
 
 @[deprecated getElem_replicate (since := "2024-06-12")]
 theorem get_replicate (a : α) {n : Nat} (m : Fin _) : (replicate n a).get m = a := by
@@ -2847,6 +2909,11 @@ theorem leftpad_suffix (n : Nat) (a : α) (l : List α) : l <:+ (leftpad n a l)
 
 theorem elem_cons_self [BEq α] [LawfulBEq α] {a : α} : (a::as).elem a = true := by simp
 
+@[simp] theorem contains_cons [BEq α] :
+    (a :: as : List α).contains x = (x == a || as.contains x) := by
+  simp only [contains, elem]
+  split <;> simp_all
+
 theorem contains_eq_any_beq [BEq α] (l : List α) (a : α) : l.contains a = l.any (a == ·) := by
   induction l with simp | cons b l => cases b == a <;> simp [*]
 
@@ -2890,7 +2957,7 @@ are often used for theorems about `Array.pop`.
 @[simp] theorem getElem_dropLast : ∀ (xs : List α) (i : Nat) (h : i < xs.dropLast.length),
     xs.dropLast[i] = xs[i]'(Nat.lt_of_lt_of_le h (length_dropLast .. ▸ Nat.pred_le _))
   | _::_::_, 0, _ => rfl
-  | _::_::_, i+1, h => getElem_dropLast _ i (Nat.add_one_lt_add_one_iff.mp h)
+  | _::_::_, i+1, _ => getElem_dropLast _ i _
 
 @[deprecated getElem_dropLast (since := "2024-06-12")]
 theorem get_dropLast (xs : List α) (i : Fin xs.dropLast.length) :
@@ -3265,10 +3332,10 @@ theorem any_eq_not_all_not (l : List α) (p : α → Bool) : l.any p = !l.all (!
 theorem all_eq_not_any_not (l : List α) (p : α → Bool) : l.all p = !l.any (!p .) := by
   simp only [not_any_eq_all_not, Bool.not_not]
 
-@[simp] theorem any_map {l : List α} {p : β → Bool} : (l.map f).any p = l.any (p ∘ f) := by
+@[simp] theorem any_map {l : List α} {p : α → Bool} : (l.map f).any p = l.any (p ∘ f) := by
   induction l with simp | cons _ _ ih => rw [ih]
 
-@[simp] theorem all_map {l : List α} {p : β → Bool} : (l.map f).all p = l.all (p ∘ f) := by
+@[simp] theorem all_map {l : List α} {p : α → Bool} : (l.map f).all p = l.all (p ∘ f) := by
   induction l with simp | cons _ _ ih => rw [ih]
 
 @[simp] theorem any_filter {l : List α} {p q : α → Bool} :
@@ -3353,137 +3420,17 @@ theorem all_eq_not_any_not (l : List α) (p : α → Bool) : l.all p = !l.any (!
     (l.insert a).all f = (f a && l.all f) := by
   simp [all_eq]
 
-/-! ### Legacy lemmas about `get`, `get?`, and `get!`.
-
-Hopefully these should not be needed, in favour of lemmas about `xs[i]`, `xs[i]?`, and `xs[i]!`,
-to which these simplify.
-
-We may consider deprecating or downstreaming these lemmas.
--/
-
-theorem get_cons_zero : get (a::l) (0 : Fin (l.length + 1)) = a := rfl
-
-theorem get_cons_succ {as : List α} {h : i + 1 < (a :: as).length} :
-  (a :: as).get ⟨i+1, h⟩ = as.get ⟨i, Nat.lt_of_succ_lt_succ h⟩ := rfl
-
-theorem get_cons_succ' {as : List α} {i : Fin as.length} :
-  (a :: as).get i.succ = as.get i := rfl
-
-theorem get_mk_zero : ∀ {l : List α} (h : 0 < l.length), l.get ⟨0, h⟩ = l.head (length_pos.mp h)
-  | _::_, _ => rfl
-
-theorem get?_zero (l : List α) : l.get? 0 = l.head? := by cases l <;> rfl
-
-/--
-If one has `l.get i` in an expression (with `i : Fin l.length`) and `h : l = l'`,
-`rw [h]` will give a "motive is not type correct" error, as it cannot rewrite the
-`i : Fin l.length` to `Fin l'.length` directly. The theorem `get_of_eq` can be used to make
-such a rewrite, with `rw [get_of_eq h]`.
--/
-theorem get_of_eq {l l' : List α} (h : l = l') (i : Fin l.length) :
-    get l i = get l' ⟨i, h ▸ i.2⟩ := by cases h; rfl
-
-theorem get!_of_get? [Inhabited α] : ∀ {l : List α} {n}, get? l n = some a → get! l n = a
-  | _a::_, 0, rfl => rfl
-  | _::l, _+1, e => get!_of_get? (l := l) e
-
-theorem get!_len_le [Inhabited α] : ∀ {l : List α} {n}, length l ≤ n → l.get! n = (default : α)
-  | [], _, _ => rfl
-  | _ :: l, _+1, h => get!_len_le (l := l) <| Nat.le_of_succ_le_succ h
-
-theorem getElem!_nil [Inhabited α] {n : Nat} : ([] : List α)[n]! = default := rfl
-
-theorem getElem!_cons_zero [Inhabited α] {l : List α} : (a::l)[0]! = a := by
-  rw [getElem!_pos] <;> simp
-
-theorem getElem!_cons_succ [Inhabited α] {l : List α} : (a::l)[n+1]! = l[n]! := by
-  by_cases h : n < l.length
-  · rw [getElem!_pos, getElem!_pos] <;> simp_all [Nat.succ_lt_succ_iff]
-  · rw [getElem!_neg, getElem!_neg] <;> simp_all [Nat.succ_lt_succ_iff]
-
-theorem getElem!_of_getElem? [Inhabited α] : ∀ {l : List α} {n : Nat}, l[n]? = some a → l[n]! = a
-  | _a::_, 0, _ => by
-    rw [getElem!_pos] <;> simp_all
-  | _::l, _+1, e => by
-    simp at e
-    simp_all [getElem!_of_getElem? (l := l) e]
-
-theorem ext_get {l₁ l₂ : List α} (hl : length l₁ = length l₂)
-    (h : ∀ n h₁ h₂, get l₁ ⟨n, h₁⟩ = get l₂ ⟨n, h₂⟩) : l₁ = l₂ :=
-  ext_getElem hl (by simp_all)
-
-theorem get_of_mem {a} {l : List α} (h : a ∈ l) : ∃ n, get l n = a := by
-  obtain ⟨n, h, e⟩ := getElem_of_mem h
-  exact ⟨⟨n, h⟩, e⟩
-
-theorem get?_of_mem {a} {l : List α} (h : a ∈ l) : ∃ n, l.get? n = some a :=
-  let ⟨⟨n, _⟩, e⟩ := get_of_mem h; ⟨n, e ▸ get?_eq_get _⟩
-
-theorem get_mem : ∀ (l : List α) n, get l n ∈ l
-  | _ :: _, ⟨0, _⟩ => .head ..
-  | _ :: l, ⟨_+1, _⟩ => .tail _ (get_mem l ..)
-
-theorem mem_of_get? {l : List α} {n a} (e : l.get? n = some a) : a ∈ l :=
-  let ⟨_, e⟩ := get?_eq_some_iff.1 e; e ▸ get_mem ..
-
-theorem mem_iff_get {a} {l : List α} : a ∈ l ↔ ∃ n, get l n = a :=
-  ⟨get_of_mem, fun ⟨_, e⟩ => e ▸ get_mem ..⟩
-
-theorem mem_iff_get? {a} {l : List α} : a ∈ l ↔ ∃ n, l.get? n = some a := by
-  simp [getElem?_eq_some_iff, Fin.exists_iff, mem_iff_get]
-
 /-! ### Deprecations -/
 
-@[deprecated getD_eq_getElem?_getD (since := "2024-06-12")]
-theorem getD_eq_get? : ∀ l n (a : α), getD l n a = (get? l n).getD a := by simp
-@[deprecated getElem_singleton (since := "2024-06-12")]
-theorem get_singleton (a : α) (n : Fin 1) : get [a] n = a := by simp
-@[deprecated getElem?_concat_length (since := "2024-06-12")]
-theorem get?_concat_length (l : List α) (a : α) : (l ++ [a]).get? l.length = some a := by simp
-@[deprecated getElem_set_self (since := "2024-06-12")]
-theorem get_set_eq {l : List α} {i : Nat} {a : α} (h : i < (l.set i a).length) :
-    (l.set i a).get ⟨i, h⟩ = a := by
-  simp
-@[deprecated getElem_set_ne (since := "2024-06-12")]
-theorem get_set_ne {l : List α} {i j : Nat} (h : i ≠ j) {a : α}
-    (hj : j < (l.set i a).length) :
-    (l.set i a).get ⟨j, hj⟩ = l.get ⟨j, by simp at hj; exact hj⟩ := by
-  simp [h]
-@[deprecated getElem_set (since := "2024-06-12")]
-theorem get_set {l : List α} {m n} {a : α} (h) :
-    (set l m a).get ⟨n, h⟩ = if m = n then a else l.get ⟨n, length_set .. ▸ h⟩ := by
-  simp [getElem_set]
-@[deprecated cons_inj_right (since := "2024-06-15")] abbrev cons_inj := @cons_inj_right
-@[deprecated ne_nil_of_length_eq_add_one (since := "2024-06-16")]
-abbrev ne_nil_of_length_eq_succ := @ne_nil_of_length_eq_add_one
-
-@[deprecated "Deprecated without replacement." (since := "2024-07-09")]
-theorem get_cons_cons_one : (a₁ :: a₂ :: as).get (1 : Fin (as.length + 2)) = a₂ := rfl
-
-@[deprecated filter_flatten (since := "2024-08-26")]
-theorem join_map_filter (p : α → Bool) (l : List (List α)) :
-    (l.map (filter p)).flatten = (l.flatten).filter p := by
-  rw [filter_flatten]
-
-@[deprecated getElem_eq_getElem?_get (since := "2024-09-04")] abbrev getElem_eq_getElem? :=
-  @getElem_eq_getElem?_get
-@[deprecated flatten_eq_nil_iff (since := "2024-09-05")] abbrev join_eq_nil := @flatten_eq_nil_iff
-@[deprecated flatten_ne_nil_iff (since := "2024-09-05")] abbrev join_ne_nil := @flatten_ne_nil_iff
-@[deprecated flatten_eq_cons_iff (since := "2024-09-05")] abbrev join_eq_cons_iff := @flatten_eq_cons_iff
-@[deprecated flatten_eq_cons_iff (since := "2024-09-05")] abbrev join_eq_cons := @flatten_eq_cons_iff
-@[deprecated flatten_eq_append_iff (since := "2024-09-05")] abbrev join_eq_append := @flatten_eq_append_iff
-@[deprecated mem_of_getElem? (since := "2024-09-06")] abbrev getElem?_mem := @mem_of_getElem?
-@[deprecated mem_of_get? (since := "2024-09-06")] abbrev get?_mem := @mem_of_get?
-@[deprecated getElem_set_self (since := "2024-09-04")] abbrev getElem_set_eq := @getElem_set_self
-@[deprecated getElem?_set_self (since := "2024-09-04")] abbrev getElem?_set_eq := @getElem?_set_self
-@[deprecated set_eq_nil_iff (since := "2024-09-05")] abbrev set_eq_nil := @set_eq_nil_iff
 
 @[deprecated flatten_nil (since := "2024-10-14")] abbrev join_nil := @flatten_nil
 @[deprecated flatten_cons (since := "2024-10-14")] abbrev join_cons := @flatten_cons
 @[deprecated length_flatten (since := "2024-10-14")] abbrev length_join := @length_flatten
 @[deprecated flatten_singleton (since := "2024-10-14")] abbrev join_singleton := @flatten_singleton
 @[deprecated mem_flatten (since := "2024-10-14")] abbrev mem_join := @mem_flatten
+@[deprecated flatten_eq_nil_iff (since := "2024-09-05")] abbrev join_eq_nil := @flatten_eq_nil_iff
 @[deprecated flatten_eq_nil_iff (since := "2024-10-14")] abbrev join_eq_nil_iff := @flatten_eq_nil_iff
+@[deprecated flatten_ne_nil_iff (since := "2024-09-05")] abbrev join_ne_nil := @flatten_ne_nil_iff
 @[deprecated flatten_ne_nil_iff (since := "2024-10-14")] abbrev join_ne_nil_iff := @flatten_ne_nil_iff
 @[deprecated exists_of_mem_flatten (since := "2024-10-14")] abbrev exists_of_mem_join := @exists_of_mem_flatten
 @[deprecated mem_flatten_of_mem (since := "2024-10-14")] abbrev mem_join_of_mem := @mem_flatten_of_mem
@@ -3497,9 +3444,16 @@ theorem join_map_filter (p : α → Bool) (l : List (List α)) :
 @[deprecated filter_flatten (since := "2024-10-14")] abbrev filter_join := @filter_flatten
 @[deprecated flatten_filter_not_isEmpty (since := "2024-10-14")] abbrev join_filter_not_isEmpty := @flatten_filter_not_isEmpty
 @[deprecated flatten_filter_ne_nil (since := "2024-10-14")] abbrev join_filter_ne_nil := @flatten_filter_ne_nil
+@[deprecated filter_flatten (since := "2024-08-26")]
+theorem join_map_filter (p : α → Bool) (l : List (List α)) :
+    (l.map (filter p)).flatten = (l.flatten).filter p := by
+  rw [filter_flatten]
 @[deprecated flatten_append (since := "2024-10-14")] abbrev join_append := @flatten_append
 @[deprecated flatten_concat (since := "2024-10-14")] abbrev join_concat := @flatten_concat
 @[deprecated flatten_flatten (since := "2024-10-14")] abbrev join_join := @flatten_flatten
+@[deprecated flatten_eq_cons_iff (since := "2024-09-05")] abbrev join_eq_cons_iff := @flatten_eq_cons_iff
+@[deprecated flatten_eq_cons_iff (since := "2024-09-05")] abbrev join_eq_cons := @flatten_eq_cons_iff
+@[deprecated flatten_eq_append_iff (since := "2024-09-05")] abbrev join_eq_append := @flatten_eq_append_iff
 @[deprecated flatten_eq_append_iff (since := "2024-10-14")] abbrev join_eq_append_iff := @flatten_eq_append_iff
 @[deprecated eq_iff_flatten_eq (since := "2024-10-14")] abbrev eq_iff_join_eq := @eq_iff_flatten_eq
 @[deprecated flatten_replicate_nil (since := "2024-10-14")] abbrev join_replicate_nil := @flatten_replicate_nil
@@ -3534,23 +3488,4 @@ theorem join_map_filter (p : α → Bool) (l : List (List α)) :
 @[deprecated any_flatMap (since := "2024-10-16")] abbrev any_bind := @any_flatMap
 @[deprecated all_flatMap (since := "2024-10-16")] abbrev all_bind := @all_flatMap
 
-@[deprecated get?_eq_none (since := "2024-11-29")] abbrev get?_len_le := @get?_eq_none
-@[deprecated getElem?_eq_some_iff (since := "2024-11-29")]
-abbrev getElem?_eq_some := @getElem?_eq_some_iff
-@[deprecated get?_eq_some_iff (since := "2024-11-29")]
-abbrev get?_eq_some := @get?_eq_some_iff
-@[deprecated LawfulGetElem.getElem?_def (since := "2024-11-29")]
-theorem getElem?_eq (l : List α) (i : Nat) :
-    l[i]? = if h : i < l.length then some l[i] else none :=
-  getElem?_def _ _
-@[deprecated getElem?_eq_none (since := "2024-11-29")] abbrev getElem?_len_le := @getElem?_eq_none
-
-@[deprecated _root_.isSome_getElem? (since := "2024-12-09")]
-theorem isSome_getElem? {l : List α} {n : Nat} : l[n]?.isSome ↔ n < l.length := by
-  simp
-
-@[deprecated _root_.isNone_getElem? (since := "2024-12-09")]
-theorem isNone_getElem? {l : List α} {n : Nat} : l[n]?.isNone ↔ l.length ≤ n := by
-  simp
-
 end List

src/Init/Data/List/MapIdx.lean

@@ -87,8 +87,8 @@ theorem mapFinIdx_eq_ofFn {as : List α} {f : Fin as.length → α → β} :
   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_iff] at m; exact m.1⟩ x := by
-  simp only [getElem?_def, length_mapFinIdx, getElem_mapFinIdx]
+    (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]
@@ -126,8 +126,7 @@ theorem mapFinIdx_singleton {a : α} {f : Fin 1 → α → β} :
 
 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_iff] at m; exact m.1⟩ x := by
+      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]
@@ -236,16 +235,16 @@ theorem getElem?_mapIdx_go : ∀ {l : List α} {arr : Array β} {i : Nat},
     (mapIdx.go f l arr)[i]? =
       if h : i < arr.size then some arr[i] else Option.map (f i) l[i - arr.size]?
   | [], arr, i => by
-    simp only [mapIdx.go, Array.toListImpl_eq, getElem?_def, Array.length_toList,
-      ← Array.getElem_toList, length_nil, Nat.not_lt_zero, ↓reduceDIte, Option.map_none']
+    simp only [mapIdx.go, Array.toListImpl_eq, getElem?_eq, Array.length_toList,
+      Array.getElem_eq_getElem_toList, length_nil, Nat.not_lt_zero, ↓reduceDIte, Option.map_none']
   | a :: l, arr, i => by
     rw [mapIdx.go, getElem?_mapIdx_go]
     simp only [Array.size_push]
     split <;> split
     · simp only [Option.some.injEq]
-      rw [← Array.getElem_toList]
+      rw [Array.getElem_eq_getElem_toList]
       simp only [Array.push_toList]
-      rw [getElem_append_left, ← Array.getElem_toList]
+      rw [getElem_append_left, Array.getElem_eq_getElem_toList]
     · have : i = arr.size := by omega
       simp_all
     · omega

src/Init/Data/List/Nat.lean

@@ -15,4 +15,3 @@ import Init.Data.List.Nat.Find
 import Init.Data.List.Nat.BEq
 import Init.Data.List.Nat.Modify
 import Init.Data.List.Nat.InsertIdx
-import Init.Data.List.Nat.Perm

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

@@ -9,7 +9,7 @@ import Init.Data.List.Basic
 
 namespace List
 
-/-! ### isEqv -/
+/-! ### isEqv-/
 
 theorem isEqv_eq_decide (a b : List α) (r) :
     isEqv a b r = if h : a.length = b.length then

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

@@ -1,54 +0,0 @@
-/-
-Copyright (c) 2024 Lean FRO. All rights reserved.
-Released under Apache 2.0 license as described in the file LICENSE.
-Authors: Kim Morrison
--/
-prelude
-import Init.Data.List.Nat.TakeDrop
-import Init.Data.List.Perm
-
-namespace List
-
-/-- Helper lemma for `set_set_perm`-/
-private theorem set_set_perm' {as : List α} {i j : Nat} (h₁ : i < as.length) (h₂ : i + j < as.length)
-    (hj : 0 < j) :
-    (as.set i as[i + j]).set (i + j) as[i] ~ as := by
-  have : as =
-      as.take i ++ as[i] :: (as.take (i + j)).drop (i + 1) ++ as[i + j] :: as.drop (i + j + 1) := by
-    simp only [getElem_cons_drop, append_assoc, cons_append]
-    rw [← drop_append_of_le_length]
-    · simp
-    · simp; omega
-  conv => lhs; congr; congr; rw [this]
-  conv => rhs; rw [this]
-  rw [set_append_left _ _ (by simp; omega)]
-  rw [set_append_right _ _ (by simp; omega)]
-  rw [set_append_right _ _ (by simp; omega)]
-  simp only [length_append, length_take, length_set, length_cons, length_drop]
-  rw [(show i - min i as.length = 0 by omega)]
-  rw [(show i + j - (min i as.length + (min (i + j) as.length - (i + 1) + 1)) = 0 by omega)]
-  simp only [set_cons_zero]
-  simp only [append_assoc]
-  apply Perm.append_left
-  apply cons_append_cons_perm
-
-theorem set_set_perm {as : List α} {i j : Nat} (h₁ : i < as.length) (h₂ : j < as.length) :
-    (as.set i as[j]).set j as[i] ~ as := by
-  if h₃ : i = j then
-    simp [h₃]
-  else
-    if h₃ : i < j then
-      let j' := j - i
-      have t : j = i + j' := by omega
-      generalize j' = j' at t
-      subst t
-      exact set_set_perm' _ _ (by omega)
-    else
-      rw [set_comm _ _ _ (by omega)]
-      let i' := i - j
-      have t : i = j + i' := by omega
-      generalize i' = i' at t
-      subst t
-      apply set_set_perm' _ _ (by omega)
-
-end List

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

@@ -345,7 +345,7 @@ theorem drop_append {l₁ l₂ : List α} (i : Nat) : drop (l₁.length + i) (l
   rw [drop_append_eq_append_drop, drop_eq_nil_of_le] <;>
     simp [Nat.add_sub_cancel_left, Nat.le_add_right]
 
-theorem set_eq_take_append_cons_drop (l : List α) (n : Nat) (a : α) :
+theorem set_eq_take_append_cons_drop {l : List α} {n : Nat} {a : α} :
     l.set n a = if n < l.length then l.take n ++ a :: l.drop (n + 1) else l := by
   split <;> rename_i h
   · ext1 m

src/Init/Data/List/Perm.lean

@@ -39,9 +39,6 @@ protected theorem Perm.symm {l₁ l₂ : List α} (h : l₁ ~ l₂) : l₂ ~ l
   | swap => exact swap ..
   | trans _ _ ih₁ ih₂ => exact trans ih₂ ih₁
 
-instance : Trans (Perm (α := α)) (Perm (α := α)) (Perm (α := α)) where
-  trans h₁ h₂ := Perm.trans h₁ h₂
-
 theorem perm_comm {l₁ l₂ : List α} : l₁ ~ l₂ ↔ l₂ ~ l₁ := ⟨Perm.symm, Perm.symm⟩
 
 theorem Perm.swap' (x y : α) {l₁ l₂ : List α} (p : l₁ ~ l₂) : y :: x :: l₁ ~ x :: y :: l₂ :=
@@ -105,7 +102,7 @@ theorem perm_append_comm : ∀ {l₁ l₂ : List α}, l₁ ++ l₂ ~ l₂ ++ l
   | _ :: _, _ => (perm_append_comm.cons _).trans perm_middle.symm
 
 theorem perm_append_comm_assoc (l₁ l₂ l₃ : List α) :
-    (l₁ ++ (l₂ ++ l₃)) ~ (l₂ ++ (l₁ ++ l₃)) := by
+    Perm (l₁ ++ (l₂ ++ l₃)) (l₂ ++ (l₁ ++ l₃)) := by
   simpa only [List.append_assoc] using perm_append_comm.append_right _
 
 theorem concat_perm (l : List α) (a : α) : concat l a ~ a :: l := by simp
@@ -136,7 +133,7 @@ theorem Perm.nil_eq {l : List α} (p : [] ~ l) : [] = l := p.symm.eq_nil.symm
 
 theorem not_perm_nil_cons (x : α) (l : List α) : ¬[] ~ x :: l := (nomatch ·.symm.eq_nil)
 
-theorem not_perm_cons_nil {l : List α} {a : α} : ¬((a::l) ~ []) :=
+theorem not_perm_cons_nil {l : List α} {a : α} : ¬(Perm (a::l) []) :=
   fun h => by simpa using h.length_eq
 
 theorem Perm.isEmpty_eq {l l' : List α} (h : Perm l l') : l.isEmpty = l'.isEmpty := by
@@ -481,15 +478,6 @@ theorem Perm.flatten {l₁ l₂ : List (List α)} (h : l₁ ~ l₂) : l₁.flatt
 
 @[deprecated Perm.flatten (since := "2024-10-14")] abbrev Perm.join := @Perm.flatten
 
-theorem cons_append_cons_perm {a b : α} {as bs : List α} :
-    a :: as ++ b :: bs ~ b :: as ++ a :: bs := by
-  suffices [[a], as, [b], bs].flatten ~ [[b], as, [a], bs].flatten by simpa
-  apply Perm.flatten
-  calc
-    [[a], as, [b], bs] ~ [as, [a], [b], bs] := Perm.swap as [a] _
-    _ ~ [as, [b], [a], bs] := Perm.cons _ (Perm.swap [b] [a] _)
-    _ ~ [[b], as, [a], bs] := Perm.swap [b] as _
-
 theorem Perm.flatMap_right {l₁ l₂ : List α} (f : α → List β) (p : l₁ ~ l₂) : l₁.flatMap f ~ l₂.flatMap f :=
   (p.map _).flatten
 

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

@@ -293,7 +293,7 @@ theorem sorted_mergeSort
     apply sorted_mergeSort trans total
 termination_by l => l.length
 
-@[deprecated sorted_mergeSort (since := "2024-09-02")] abbrev mergeSort_sorted := @sorted_mergeSort
+@[deprecated (since := "2024-09-02")] abbrev mergeSort_sorted := @sorted_mergeSort
 
 /--
 If the input list is already sorted, then `mergeSort` does not change the list.
@@ -429,8 +429,7 @@ theorem sublist_mergeSort
         ((fun w => Sublist.of_sublist_append_right w h') fun b m₁ m₃ =>
           (Bool.eq_not_self true).mp ((rel_of_pairwise_cons hc m₁).symm.trans (h₃ b m₃))))
 
-@[deprecated sublist_mergeSort (since := "2024-09-02")]
-abbrev mergeSort_stable := @sublist_mergeSort
+@[deprecated (since := "2024-09-02")] abbrev mergeSort_stable := @sublist_mergeSort
 
 /--
 Another statement of stability of merge sort.
@@ -443,8 +442,7 @@ theorem pair_sublist_mergeSort
     (hab : le a b) (h : [a, b] <+ l) : [a, b] <+ mergeSort l le :=
   sublist_mergeSort trans total (pairwise_pair.mpr hab) h
 
-@[deprecated pair_sublist_mergeSort(since := "2024-09-02")]
-abbrev mergeSort_stable_pair := @pair_sublist_mergeSort
+@[deprecated (since := "2024-09-02")] abbrev mergeSort_stable_pair := @pair_sublist_mergeSort
 
 theorem map_merge {f : α → β} {r : α → α → Bool} {s : β → β → Bool} {l l' : List α}
     (hl : ∀ a ∈ l, ∀ b ∈ l', r a b = s (f a) (f b)) :

src/Init/Data/List/Sublist.lean

@@ -417,7 +417,7 @@ theorem Sublist.of_sublist_append_left (w : ∀ a, a ∈ l → a ∉ l₂) (h :
   obtain ⟨l₁', l₂', rfl, h₁, h₂⟩ := h
   have : l₂' = [] := by
     rw [eq_nil_iff_forall_not_mem]
-    exact fun x m => w x (mem_append_right l₁' m) (h₂.mem m)
+    exact fun x m => w x (mem_append_of_mem_right l₁' m) (h₂.mem m)
   simp_all
 
 theorem Sublist.of_sublist_append_right (w : ∀ a, a ∈ l → a ∉ l₁) (h : l <+ l₁ ++ l₂) : l <+ l₂ := by
@@ -425,7 +425,7 @@ theorem Sublist.of_sublist_append_right (w : ∀ a, a ∈ l → a ∉ l₁) (h :
   obtain ⟨l₁', l₂', rfl, h₁, h₂⟩ := h
   have : l₁' = [] := by
     rw [eq_nil_iff_forall_not_mem]
-    exact fun x m => w x (mem_append_left l₂' m) (h₁.mem m)
+    exact fun x m => w x (mem_append_of_mem_left l₂' m) (h₁.mem m)
   simp_all
 
 theorem Sublist.middle {l : List α} (h : l <+ l₁ ++ l₂) (a : α) : l <+ l₁ ++ a :: l₂ := by
@@ -835,13 +835,13 @@ 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 := [2]) [← Nat.and_forall_add_one]
+      rw (occs := .pos [2]) [← Nat.and_forall_add_one]
       simp [Nat.succ_lt_succ_iff, eq_comm]
 
 theorem isPrefix_iff_getElem {l₁ l₂ : List α} :
     l₁ <+: l₂ ↔ ∃ (h : l₁.length ≤ l₂.length), ∀ x (hx : x < l₁.length),
       l₁[x] = l₂[x]'(Nat.lt_of_lt_of_le hx h) where
-  mp h := ⟨h.length_le, fun _ h' ↦ h.getElem h'⟩
+  mp h := ⟨h.length_le, fun _ _ ↦ h.getElem _⟩
   mpr h := by
     obtain ⟨hl, h⟩ := h
     induction l₂ generalizing l₁ with

src/Init/Data/List/TakeDrop.lean

@@ -65,13 +65,13 @@ theorem lt_length_of_take_ne_self {l : List α} {n} (h : l.take n ≠ l) : n < l
 theorem getElem_cons_drop : ∀ (l : List α) (i : Nat) (h : i < l.length),
     l[i] :: drop (i + 1) l = drop i l
   | _::_, 0, _ => rfl
-  | _::_, i+1, h => getElem_cons_drop _ i (Nat.add_one_lt_add_one_iff.mp h)
+  | _::_, i+1, _ => getElem_cons_drop _ i _
 
 @[deprecated getElem_cons_drop (since := "2024-06-12")]
 theorem get_cons_drop (l : List α) (i) : get l i :: drop (i + 1) l = drop i l := by
   simp
 
-theorem drop_eq_getElem_cons {n} {l : List α} (h : n < l.length) : drop n l = l[n] :: drop (n + 1) l :=
+theorem drop_eq_getElem_cons {n} {l : List α} (h) : drop n l = l[n] :: drop (n + 1) l :=
   (getElem_cons_drop _ n h).symm
 
 @[deprecated drop_eq_getElem_cons (since := "2024-06-12")]
@@ -192,24 +192,6 @@ theorem take_concat_get (l : List α) (i : Nat) (h : i < l.length) :
   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]
 
-@[simp] theorem take_append_getElem (l : List α) (i : Nat) (h : i < l.length) :
-    (l.take i) ++ [l[i]] = l.take (i+1) := by
-  simpa using take_concat_get l i h
-
-@[simp] theorem take_append_getLast (l : List α) (h : l ≠ []) :
-    (l.take (l.length - 1)) ++ [l.getLast h] = l := by
-  rw [getLast_eq_getElem]
-  cases l
-  · contradiction
-  · simp
-
-@[simp] theorem take_append_getLast? (l : List α) :
-    (l.take (l.length - 1)) ++ l.getLast?.toList = l := by
-  match l with
-  | [] => simp
-  | x :: xs =>
-    simpa using take_append_getLast (x :: xs) (by simp)
-
 @[deprecated take_succ_cons (since := "2024-07-25")]
 theorem take_cons_succ : (a::as).take (i+1) = a :: as.take i := rfl
 
@@ -242,7 +224,7 @@ theorem take_succ {l : List α} {n : Nat} : l.take (n + 1) = l.take n ++ l[n]?.t
     · simp only [take, Option.toList, getElem?_cons_zero, nil_append]
     · simp only [take, hl, getElem?_cons_succ, cons_append]
 
-@[deprecated "Deprecated without replacement." (since := "2024-07-25")]
+@[deprecated (since := "2024-07-25")]
 theorem drop_sizeOf_le [SizeOf α] (l : List α) (n : Nat) : sizeOf (l.drop n) ≤ sizeOf l := by
   induction l generalizing n with
   | nil => rw [drop_nil]; apply Nat.le_refl

src/Init/Data/List/ToArray.lean

@@ -1,366 +1,23 @@
 /-
-Copyright (c) 2022 Mario Carneiro. All rights reserved.
+Copyright (c) 2024 Lean FRO. All rights reserved.
 Released under Apache 2.0 license as described in the file LICENSE.
-Authors: Mario Carneiro
+Authors: Henrik Böving
 -/
 prelude
-import Init.Data.List.Impl
-import Init.Data.List.Nat.Erase
-import Init.Data.List.Monadic
+import Init.Data.List.Basic
 
-/-! ### Lemmas about `List.toArray`.
-
-We prefer to pull `List.toArray` outwards past `Array` operations.
+/--
+Auxiliary definition for `List.toArray`.
+`List.toArrayAux as r = r ++ as.toArray`
 -/
-namespace List
+@[inline_if_reduce]
+def List.toArrayAux : List α → Array α → Array α
+  | nil,       r => r
+  | cons a as, r => toArrayAux as (r.push a)
 
-open Array
-
-theorem toArray_inj {a b : List α} (h : a.toArray = b.toArray) : a = b := by
-  cases a with
-  | nil => simpa using h
-  | cons a as =>
-    cases b with
-    | nil => simp at h
-    | cons b bs => simpa using h
-
-@[simp] theorem size_toArrayAux {a : List α} {b : Array α} :
-    (a.toArrayAux b).size = b.size + a.length := by
-  simp [size]
-
-@[simp] theorem push_toArray (l : List α) (a : α) : l.toArray.push a = (l ++ [a]).toArray := by
-  apply ext'
-  simp
-
-/-- Unapplied variant of `push_toArray`, useful for monadic reasoning. -/
-@[simp] theorem push_toArray_fun (l : List α) : l.toArray.push = fun a => (l ++ [a]).toArray := by
-  funext a
-  simp
-
-@[simp] theorem isEmpty_toArray (l : List α) : l.toArray.isEmpty = l.isEmpty := by
-  cases l <;> simp
-
-@[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 (l : List α) : l.toArray.back? = l.getLast? := by
-  simp [back?, List.getLast?_eq_getElem?]
-
-@[simp] theorem set_toArray (l : List α) (i : Nat) (a : α) (h : i < l.length) :
-    (l.toArray.set i a) = (l.set i a).toArray := rfl
-
-@[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) :
-    Array.forIn'.loop l.toArray f i h b =
-      forIn' (l.drop (l.length - i)) b (fun a m b => f a (by simpa using mem_of_mem_drop m) b) := 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]
-    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)]
-      simp only [Option.toList_some, singleton_append]
-    simp [t]
-    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 : (a : α) → a ∈ l.toArray → β → m (ForInStep β)) :
-    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
-
-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
-  rw [foldrM_eq_reverse_foldlM_toList]
-  simp
-
-theorem foldlM_toArray [Monad m] (f : β → α → m β) (init : β) (l : List α) :
-    l.toArray.foldlM f init = l.foldlM f init := by
-  rw [foldlM_toList]
-
-theorem foldr_toArray (f : α → β → β) (init : β) (l : List α) :
-    l.toArray.foldr f init = l.foldr f init := by
-  rw [foldr_toList]
-
-theorem foldl_toArray (f : β → α → β) (init : β) (l : List α) :
-    l.toArray.foldl f init = l.foldl f init := by
-  rw [foldl_toList]
-
-/-- Variant of `foldrM_toArray` with a side condition for the `start` argument. -/
-@[simp] theorem foldrM_toArray' [Monad m] (f : α → β → m β) (init : β) (l : List α)
-    (h : start = l.toArray.size) :
-    l.toArray.foldrM f init start 0 = l.foldrM f init := by
-  subst h
-  rw [foldrM_eq_reverse_foldlM_toList]
-  simp
-
-/-- Variant of `foldlM_toArray` with a side condition for the `stop` argument. -/
-@[simp] theorem foldlM_toArray' [Monad m] (f : β → α → m β) (init : β) (l : List α)
-    (h : stop = l.toArray.size) :
-    l.toArray.foldlM f init 0 stop = l.foldlM f init := by
-  subst h
-  rw [foldlM_toList]
-
-/-- Variant of `foldr_toArray` with a side condition for the `start` argument. -/
-@[simp] theorem foldr_toArray' (f : α → β → β) (init : β) (l : List α)
-    (h : start = l.toArray.size) :
-    l.toArray.foldr f init start 0 = l.foldr f init := by
-  subst h
-  rw [foldr_toList]
-
-/-- Variant of `foldl_toArray` with a side condition for the `stop` argument. -/
-@[simp] theorem foldl_toArray' (f : β → α → β) (init : β) (l : List α)
-    (h : stop = l.toArray.size) :
-    l.toArray.foldl f init 0 stop = l.foldl f init := by
-  subst h
-  rw [foldl_toList]
-
-@[simp] theorem append_toArray (l₁ l₂ : List α) :
-    l₁.toArray ++ l₂.toArray = (l₁ ++ l₂).toArray := by
-  apply ext'
-  simp
-
-@[simp] theorem push_append_toArray {as : Array α} {a : α} {bs : List α} : as.push a ++ bs.toArray = as ++ (a ::bs).toArray := by
-  cases as
-  simp
-
-@[simp] theorem foldl_push {l : List α} {as : Array α} : l.foldl Array.push as = as ++ l.toArray := by
-  induction l generalizing as <;> simp [*]
-
-@[simp] theorem foldr_push {l : List α} {as : Array α} : l.foldr (fun a b => push b a) as = as ++ l.reverse.toArray := by
-  rw [foldr_eq_foldl_reverse, foldl_push]
-
-@[simp] theorem findSomeM?_toArray [Monad m] [LawfulMonad m] (f : α → m (Option β)) (l : List α) :
-    l.toArray.findSomeM? f = l.findSomeM? f := by
-  rw [Array.findSomeM?]
-  simp only [bind_pure_comp, map_pure, forIn_toArray]
-  induction l with
-  | nil => simp
-  | cons a l ih =>
-    simp only [forIn_cons, LawfulMonad.bind_assoc, findSomeM?]
-    congr
-    ext1 (_|_) <;> simp [ih]
-
-theorem findSomeRevM?_find_toArray [Monad m] [LawfulMonad m] (f : α → m (Option β)) (l : List α)
-    (i : Nat) (h) :
-    findSomeRevM?.find f l.toArray i h = (l.take i).reverse.findSomeM? f := by
-  induction i generalizing l with
-  | zero => simp [Array.findSomeRevM?.find.eq_def]
-  | succ i ih =>
-    rw [size_toArray] at h
-    rw [Array.findSomeRevM?.find, take_succ, getElem?_eq_getElem (by omega)]
-    simp only [ih, reverse_append]
-    congr
-    ext1 (_|_) <;> simp
-
--- This is not marked as `@[simp]` as later we simplify all occurrences of `findSomeRevM?`.
-theorem findSomeRevM?_toArray [Monad m] [LawfulMonad m] (f : α → m (Option β)) (l : List α) :
-    l.toArray.findSomeRevM? f = l.reverse.findSomeM? f := by
-  simp [Array.findSomeRevM?, findSomeRevM?_find_toArray]
-
--- This is not marked as `@[simp]` as later we simplify all occurrences of `findRevM?`.
-theorem findRevM?_toArray [Monad m] [LawfulMonad m] (f : α → m Bool) (l : List α) :
-    l.toArray.findRevM? f = l.reverse.findM? f := by
-  rw [Array.findRevM?, findSomeRevM?_toArray, findM?_eq_findSomeM?]
-
-@[simp] theorem findM?_toArray [Monad m] [LawfulMonad m] (f : α → m Bool) (l : List α) :
-    l.toArray.findM? f = l.findM? f := by
-  rw [Array.findM?]
-  simp only [bind_pure_comp, map_pure, forIn_toArray]
-  induction l with
-  | nil => simp
-  | cons a l ih =>
-    simp only [forIn_cons, LawfulMonad.bind_assoc, findM?]
-    congr
-    ext1 (_|_) <;> simp [ih]
-
-@[simp] theorem findSome?_toArray (f : α → Option β) (l : List α) :
-    l.toArray.findSome? f = l.findSome? f := by
-  rw [Array.findSome?, ← findSomeM?_id, findSomeM?_toArray, Id.run]
-
-@[simp] theorem find?_toArray (f : α → Bool) (l : List α) :
-    l.toArray.find? f = l.find? f := by
-  rw [Array.find?]
-  simp only [Id.run, Id, Id.pure_eq, Id.bind_eq, forIn_toArray]
-  induction l with
-  | nil => simp
-  | cons a l ih =>
-    simp only [forIn_cons, Id.pure_eq, Id.bind_eq, find?]
-    by_cases f a <;> simp_all
-
-theorem isPrefixOfAux_toArray_succ [BEq α] (l₁ l₂ : List α) (hle : l₁.length ≤ l₂.length) (i : Nat) :
-    Array.isPrefixOfAux l₁.toArray l₂.toArray hle (i + 1) =
-      Array.isPrefixOfAux l₁.tail.toArray l₂.tail.toArray (by simp; omega) i := by
-  rw [Array.isPrefixOfAux]
-  conv => rhs; rw [Array.isPrefixOfAux]
-  simp only [size_toArray, getElem_toArray, Bool.if_false_right, length_tail, getElem_tail]
-  split <;> rename_i h₁ <;> split <;> rename_i h₂
-  · rw [isPrefixOfAux_toArray_succ]
-  · omega
-  · omega
-  · rfl
-
-theorem isPrefixOfAux_toArray_succ' [BEq α] (l₁ l₂ : List α) (hle : l₁.length ≤ l₂.length) (i : Nat) :
-    Array.isPrefixOfAux l₁.toArray l₂.toArray hle (i + 1) =
-      Array.isPrefixOfAux (l₁.drop (i+1)).toArray (l₂.drop (i+1)).toArray (by simp; omega) 0 := by
-  induction i generalizing l₁ l₂ with
-  | zero => simp [isPrefixOfAux_toArray_succ]
-  | succ i ih =>
-    rw [isPrefixOfAux_toArray_succ, ih]
-    simp
-
-theorem isPrefixOfAux_toArray_zero [BEq α] (l₁ l₂ : List α) (hle : l₁.length ≤ l₂.length) :
-    Array.isPrefixOfAux l₁.toArray l₂.toArray hle 0 =
-      l₁.isPrefixOf l₂ := by
-  rw [Array.isPrefixOfAux]
-  match l₁, l₂ with
-  | [], _ => rw [dif_neg] <;> simp
-  | _::_, [] => simp at hle
-  | a::l₁, b::l₂ =>
-    simp [isPrefixOf_cons₂, isPrefixOfAux_toArray_succ', isPrefixOfAux_toArray_zero]
-
-@[simp] theorem isPrefixOf_toArray [BEq α] (l₁ l₂ : List α) :
-    l₁.toArray.isPrefixOf l₂.toArray = l₁.isPrefixOf l₂ := by
-  rw [Array.isPrefixOf]
-  split <;> rename_i h
-  · simp [isPrefixOfAux_toArray_zero]
-  · simp only [Bool.false_eq]
-    induction l₁ generalizing l₂ with
-    | nil => simp at h
-    | cons a l₁ ih =>
-      cases l₂ with
-      | nil => simp
-      | cons b l₂ =>
-        simp only [isPrefixOf_cons₂, Bool.and_eq_false_imp]
-        intro w
-        rw [ih]
-        simp_all
-
-theorem zipWithAux_toArray_succ (as : List α) (bs : List β) (f : α → β → γ) (i : Nat) (cs : Array γ) :
-    zipWithAux as.toArray bs.toArray f (i + 1) cs = zipWithAux as.tail.toArray bs.tail.toArray f i cs := by
-  rw [zipWithAux]
-  conv => rhs; rw [zipWithAux]
-  simp only [size_toArray, getElem_toArray, length_tail, getElem_tail]
-  split <;> rename_i h₁
-  · split <;> rename_i h₂
-    · rw [dif_pos (by omega), dif_pos (by omega), zipWithAux_toArray_succ]
-    · rw [dif_pos (by omega)]
-      rw [dif_neg (by omega)]
-  · rw [dif_neg (by omega)]
-
-theorem zipWithAux_toArray_succ' (as : List α) (bs : List β) (f : α → β → γ) (i : Nat) (cs : Array γ) :
-    zipWithAux as.toArray bs.toArray f (i + 1) cs = zipWithAux (as.drop (i+1)).toArray (bs.drop (i+1)).toArray f 0 cs := by
-  induction i generalizing as bs cs with
-  | zero => simp [zipWithAux_toArray_succ]
-  | succ i ih =>
-    rw [zipWithAux_toArray_succ, ih]
-    simp
-
-theorem zipWithAux_toArray_zero (f : α → β → γ) (as : List α) (bs : List β) (cs : Array γ) :
-    zipWithAux as.toArray bs.toArray f 0 cs = cs ++ (List.zipWith f as bs).toArray := by
-  rw [Array.zipWithAux]
-  match as, bs with
-  | [], _ => simp
-  | _, [] => simp
-  | a :: as, b :: bs =>
-    simp [zipWith_cons_cons, zipWithAux_toArray_succ', zipWithAux_toArray_zero, push_append_toArray]
-
-@[simp] theorem zipWith_toArray (as : List α) (bs : List β) (f : α → β → γ) :
-    Array.zipWith as.toArray bs.toArray f = (List.zipWith f as bs).toArray := by
-  rw [Array.zipWith]
-  simp [zipWithAux_toArray_zero]
-
-@[simp] theorem zip_toArray (as : List α) (bs : List β) :
-    Array.zip as.toArray bs.toArray = (List.zip as bs).toArray := by
-  simp [Array.zip, zipWith_toArray, zip]
-
-theorem zipWithAll_go_toArray (as : List α) (bs : List β) (f : Option α → Option β → γ) (i : Nat) (cs : Array γ) :
-    zipWithAll.go f as.toArray bs.toArray i cs = cs ++ (List.zipWithAll f (as.drop i) (bs.drop i)).toArray := by
-  unfold zipWithAll.go
-  split <;> rename_i h
-  · rw [zipWithAll_go_toArray]
-    simp at h
-    simp only [getElem?_toArray, push_append_toArray]
-    if ha : i < as.length then
-      if hb : i < bs.length then
-        rw [List.drop_eq_getElem_cons ha, List.drop_eq_getElem_cons hb]
-        simp only [ha, hb, getElem?_eq_getElem, zipWithAll_cons_cons]
-      else
-        simp only [Nat.not_lt] at hb
-        rw [List.drop_eq_getElem_cons ha]
-        rw [(drop_eq_nil_iff (l := bs)).mpr (by omega), (drop_eq_nil_iff (l := bs)).mpr (by omega)]
-        simp only [zipWithAll_nil, map_drop, map_cons]
-        rw [getElem?_eq_getElem ha]
-        rw [getElem?_eq_none hb]
-    else
-      if hb : i < bs.length then
-        simp only [Nat.not_lt] at ha
-        rw [List.drop_eq_getElem_cons hb]
-        rw [(drop_eq_nil_iff (l := as)).mpr (by omega), (drop_eq_nil_iff (l := as)).mpr (by omega)]
-        simp only [nil_zipWithAll, map_drop, map_cons]
-        rw [getElem?_eq_getElem hb]
-        rw [getElem?_eq_none ha]
-      else
-        omega
-  · simp only [size_toArray, Nat.not_lt] at h
-    rw [drop_eq_nil_of_le (by omega), drop_eq_nil_of_le (by omega)]
-    simp
-  termination_by max as.length bs.length - i
-  decreasing_by simp_wf; decreasing_trivial_pre_omega
-
-@[simp] theorem zipWithAll_toArray (f : Option α → Option β → γ) (as : List α) (bs : List β) :
-    Array.zipWithAll as.toArray bs.toArray f = (List.zipWithAll f as bs).toArray := by
-  simp [Array.zipWithAll, zipWithAll_go_toArray]
-
-@[simp] theorem toArray_appendList (l₁ l₂ : List α) :
-    l₁.toArray ++ l₂ = (l₁ ++ l₂).toArray := by
-  apply ext'
-  simp
-
-@[simp] theorem pop_toArray (l : List α) : l.toArray.pop = l.dropLast.toArray := by
-  apply 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]
-
-end List
+/-- Convert a `List α` into an `Array α`. This is O(n) in the length of the list.  -/
+-- This function is exported to C, where it is called by `Array.mk`
+-- (the constructor) to implement this functionality.
+@[inline, match_pattern, pp_nodot, export lean_list_to_array]
+def List.toArrayImpl (as : List α) : Array α :=
+  as.toArrayAux (Array.mkEmpty as.length)

src/Init/Data/List/ToArrayImpl.lean

@@ -1,23 +0,0 @@
-/-
-Copyright (c) 2024 Lean FRO. All rights reserved.
-Released under Apache 2.0 license as described in the file LICENSE.
-Authors: Henrik Böving
--/
-prelude
-import Init.Data.List.Basic
-
-/--
-Auxiliary definition for `List.toArray`.
-`List.toArrayAux as r = r ++ as.toArray`
--/
-@[inline_if_reduce]
-def List.toArrayAux : List α → Array α → Array α
-  | nil,       r => r
-  | cons a as, r => toArrayAux as (r.push a)
-
-/-- Convert a `List α` into an `Array α`. This is O(n) in the length of the list.  -/
--- This function is exported to C, where it is called by `Array.mk`
--- (the constructor) to implement this functionality.
-@[inline, match_pattern, pp_nodot, export lean_list_to_array]
-def List.toArrayImpl (as : List α) : Array α :=
-  as.toArrayAux (Array.mkEmpty as.length)

src/Init/Data/Nat.lean

@@ -20,4 +20,3 @@ import Init.Data.Nat.Mod
 import Init.Data.Nat.Lcm
 import Init.Data.Nat.Compare
 import Init.Data.Nat.Simproc
-import Init.Data.Nat.Fold

src/Init/Data/Nat/Basic.lean

@@ -35,6 +35,52 @@ Used as the default `Nat` eliminator by the `cases` tactic. -/
 protected abbrev casesAuxOn {motive : Nat → Sort u} (t : Nat) (zero : motive 0) (succ : (n : Nat) → motive (n + 1)) : motive t :=
   Nat.casesOn t zero succ
 
+/--
+`Nat.fold` evaluates `f` on the numbers up to `n` exclusive, in increasing order:
+* `Nat.fold f 3 init = init |> f 0 |> f 1 |> f 2`
+-/
+@[specialize] def fold {α : Type u} (f : Nat → α → α) : (n : Nat) → (init : α) → α
+  | 0,      a => a
+  | succ n, a => f n (fold f n a)
+
+/-- Tail-recursive version of `Nat.fold`. -/
+@[inline] def foldTR {α : Type u} (f : Nat → α → α) (n : Nat) (init : α) : α :=
+  let rec @[specialize] loop
+    | 0,      a => a
+    | succ m, a => loop m (f (n - succ m) a)
+  loop n init
+
+/--
+`Nat.foldRev` evaluates `f` on the numbers up to `n` exclusive, in decreasing order:
+* `Nat.foldRev f 3 init = f 0 <| f 1 <| f 2 <| init`
+-/
+@[specialize] def foldRev {α : Type u} (f : Nat → α → α) : (n : Nat) → (init : α) → α
+  | 0,      a => a
+  | succ n, a => foldRev f n (f n a)
+
+/-- `any f n = true` iff there is `i in [0, n-1]` s.t. `f i = true` -/
+@[specialize] def any (f : Nat → Bool) : Nat → Bool
+  | 0      => false
+  | succ n => any f n || f n
+
+/-- Tail-recursive version of `Nat.any`. -/
+@[inline] def anyTR (f : Nat → Bool) (n : Nat) : Bool :=
+  let rec @[specialize] loop : Nat → Bool
+    | 0      => false
+    | succ m => f (n - succ m) || loop m
+  loop n
+
+/-- `all f n = true` iff every `i in [0, n-1]` satisfies `f i = true` -/
+@[specialize] def all (f : Nat → Bool) : Nat → Bool
+  | 0      => true
+  | succ n => all f n && f n
+
+/-- Tail-recursive version of `Nat.all`. -/
+@[inline] def allTR (f : Nat → Bool) (n : Nat) : Bool :=
+  let rec @[specialize] loop : Nat → Bool
+    | 0      => true
+    | succ m => f (n - succ m) && loop m
+  loop n
 
 /--
 `Nat.repeat f n a` is `f^(n) a`; that is, it iterates `f` `n` times on `a`.
@@ -789,7 +835,7 @@ theorem pred_lt_of_lt {n m : Nat} (h : m < n) : pred n < n :=
   pred_lt (not_eq_zero_of_lt h)
 
 set_option linter.missingDocs false in
-@[deprecated pred_lt_of_lt (since := "2024-06-01")] abbrev pred_lt' := @pred_lt_of_lt
+@[deprecated (since := "2024-06-01")] abbrev pred_lt' := @pred_lt_of_lt
 
 theorem sub_one_lt_of_lt {n m : Nat} (h : m < n) : n - 1 < n :=
   sub_one_lt (not_eq_zero_of_lt h)
@@ -1075,7 +1121,7 @@ theorem pred_mul (n m : Nat) : pred n * m = n * m - m := by
   | succ n => rw [Nat.pred_succ, succ_mul, Nat.add_sub_cancel]
 
 set_option linter.missingDocs false in
-@[deprecated pred_mul (since := "2024-06-01")] abbrev mul_pred_left := @pred_mul
+@[deprecated (since := "2024-06-01")] abbrev mul_pred_left := @pred_mul
 
 protected theorem sub_one_mul  (n m : Nat) : (n - 1) * m = n * m - m := by
   cases n with
@@ -1087,7 +1133,7 @@ theorem mul_pred (n m : Nat) : n * pred m = n * m - n := by
   rw [Nat.mul_comm, pred_mul, Nat.mul_comm]
 
 set_option linter.missingDocs false in
-@[deprecated mul_pred (since := "2024-06-01")] abbrev mul_pred_right := @mul_pred
+@[deprecated (since := "2024-06-01")] abbrev mul_pred_right := @mul_pred
 
 theorem mul_sub_one (n m : Nat) : n * (m - 1) = n * m - n := by
   rw [Nat.mul_comm, Nat.sub_one_mul , Nat.mul_comm]
@@ -1112,6 +1158,33 @@ theorem not_lt_eq (a b : Nat) : (¬ (a < b)) = (b ≤ a) :=
 theorem not_gt_eq (a b : Nat) : (¬ (a > b)) = (a ≤ b) :=
   not_lt_eq b a
 
+/-! # csimp theorems -/
+
+@[csimp] theorem fold_eq_foldTR : @fold = @foldTR :=
+  funext fun α => funext fun f => funext fun n => funext fun init =>
+  let rec go : ∀ m n, foldTR.loop f (m + n) m (fold f n init) = fold f (m + n) init
+    | 0,      n => by simp [foldTR.loop]
+    | succ m, n => by rw [foldTR.loop, add_sub_self_left, succ_add]; exact go m (succ n)
+  (go n 0).symm
+
+@[csimp] theorem any_eq_anyTR : @any = @anyTR :=
+  funext fun f => funext fun n =>
+  let rec go : ∀ m n,  (any f n || anyTR.loop f (m + n) m) = any f (m + n)
+    | 0,      n => by simp [anyTR.loop]
+    | succ m, n => by
+      rw [anyTR.loop, add_sub_self_left, ← Bool.or_assoc, succ_add]
+      exact go m (succ n)
+  (go n 0).symm
+
+@[csimp] theorem all_eq_allTR : @all = @allTR :=
+  funext fun f => funext fun n =>
+  let rec go : ∀ m n,  (all f n && allTR.loop f (m + n) m) = all f (m + n)
+    | 0,      n => by simp [allTR.loop]
+    | succ m, n => by
+      rw [allTR.loop, add_sub_self_left, ← Bool.and_assoc, succ_add]
+      exact go m (succ n)
+  (go n 0).symm
+
 @[csimp] theorem repeat_eq_repeatTR : @repeat = @repeatTR :=
   funext fun α => funext fun f => funext fun n => funext fun init =>
   let rec go : ∀ m n, repeatTR.loop f m (repeat f n init) = repeat f (m + n) init
@@ -1120,3 +1193,31 @@ theorem not_gt_eq (a b : Nat) : (¬ (a > b)) = (a ≤ b) :=
   (go n 0).symm
 
 end Nat
+
+namespace Prod
+
+/--
+`(start, stop).foldI f a` evaluates `f` on all the numbers
+from `start` (inclusive) to `stop` (exclusive) in increasing order:
+* `(5, 8).foldI f init = init |> f 5 |> f 6 |> f 7`
+-/
+@[inline] def foldI {α : Type u} (f : Nat → α → α) (i : Nat × Nat) (a : α) : α :=
+  Nat.foldTR.loop f i.2 (i.2 - i.1) a
+
+/--
+`(start, stop).anyI f a` returns true if `f` is true for some natural number
+from `start` (inclusive) to `stop` (exclusive):
+* `(5, 8).anyI f = f 5 || f 6 || f 7`
+-/
+@[inline] def anyI (f : Nat → Bool) (i : Nat × Nat) : Bool :=
+  Nat.anyTR.loop f i.2 (i.2 - i.1)
+
+/--
+`(start, stop).allI f a` returns true if `f` is true for all natural numbers
+from `start` (inclusive) to `stop` (exclusive):
+* `(5, 8).anyI f = f 5 && f 6 && f 7`
+-/
+@[inline] def allI (f : Nat → Bool) (i : Nat × Nat) : Bool :=
+  Nat.allTR.loop f i.2 (i.2 - i.1)
+
+end Prod

src/Init/Data/Nat/Bitwise/Basic.lean

@@ -71,9 +71,6 @@ theorem shiftRight_eq_div_pow (m : Nat) : ∀ n, m >>> n = m / 2 ^ n
     rw [shiftRight_add, shiftRight_eq_div_pow m k]
     simp [Nat.div_div_eq_div_mul, ← Nat.pow_succ, shiftRight_succ]
 
-theorem shiftRight_eq_zero (m n : Nat) (hn : m < 2^n) : m >>> n = 0 := by
-  simp [Nat.shiftRight_eq_div_pow, Nat.div_eq_of_lt hn]
-
 /-!
 ### testBit
 We define an operation for testing individual bits in the binary representation

src/Init/Data/Nat/Control.lean

@@ -6,51 +6,50 @@ Author: Leonardo de Moura
 prelude
 import Init.Control.Basic
 import Init.Data.Nat.Basic
-import Init.Omega
 
 namespace Nat
 universe u v
 
-@[inline] def forM {m} [Monad m] (n : Nat) (f : (i : Nat) → i < n → m Unit) : m Unit :=
-  let rec @[specialize] loop : ∀ i, i ≤ n → m Unit
-    | 0,   _ => pure ()
-    | i+1, h => do f (n-i-1) (by omega); loop i (Nat.le_of_succ_le h)
-  loop n (by simp)
+@[inline] def forM {m} [Monad m] (n : Nat) (f : Nat → m Unit) : m Unit :=
+  let rec @[specialize] loop
+    | 0   => pure ()
+    | i+1 => do f (n-i-1); loop i
+  loop n
 
-@[inline] def forRevM {m} [Monad m] (n : Nat) (f : (i : Nat) → i < n → m Unit) : m Unit :=
-  let rec @[specialize] loop : ∀ i, i ≤ n → m Unit
-    | 0,   _ => pure ()
-    | i+1, h => do f i (by omega); loop i (Nat.le_of_succ_le h)
-  loop n (by simp)
+@[inline] def forRevM {m} [Monad m] (n : Nat) (f : Nat → m Unit) : m Unit :=
+  let rec @[specialize] loop
+    | 0   => pure ()
+    | i+1 => do f i; loop i
+  loop n
 
-@[inline] def foldM {α : Type u} {m : Type u → Type v} [Monad m] (n : Nat) (f : (i : Nat) → i < n → α → m α) (init : α) : m α :=
-  let rec @[specialize] loop : ∀ i, i ≤ n → α → m α
-    | 0,   h, a => pure a
-    | i+1, h, a => f (n-i-1) (by omega) a >>= loop i (Nat.le_of_succ_le h)
-  loop n (by omega) init
+@[inline] def foldM {α : Type u} {m : Type u → Type v} [Monad m] (f : Nat → α → m α) (init : α) (n : Nat) : m α :=
+  let rec @[specialize] loop
+    | 0,   a => pure a
+    | i+1, a => f (n-i-1) a >>= loop i
+  loop n init
 
-@[inline] def foldRevM {α : Type u} {m : Type u → Type v} [Monad m] (n : Nat) (f : (i : Nat) → i < n → α → m α) (init : α) : m α :=
-  let rec @[specialize] loop : ∀ i, i ≤ n → α → m α
-    | 0,   h, a => pure a
-    | i+1, h, a => f i (by omega) a >>= loop i (Nat.le_of_succ_le h)
-  loop n (by omega) init
+@[inline] def foldRevM {α : Type u} {m : Type u → Type v} [Monad m] (f : Nat → α → m α) (init : α) (n : Nat) : m α :=
+  let rec @[specialize] loop
+    | 0,   a => pure a
+    | i+1, a => f i a >>= loop i
+  loop n init
 
-@[inline] def allM {m} [Monad m] (n : Nat) (p : (i : Nat) → i < n → m Bool) : m Bool :=
-  let rec @[specialize] loop : ∀ i, i ≤ n → m Bool
-    | 0,   _ => pure true
-    | i+1 , h => do
-      match (← p (n-i-1) (by omega)) with
-      | true  => loop i (by omega)
+@[inline] def allM {m} [Monad m] (n : Nat) (p : Nat → m Bool) : m Bool :=
+  let rec @[specialize] loop
+    | 0   => pure true
+    | i+1 => do
+      match (← p (n-i-1)) with
+      | true  => loop i
       | false => pure false
-  loop n (by simp)
+  loop n
 
-@[inline] def anyM {m} [Monad m] (n : Nat) (p : (i : Nat) → i < n → m Bool) : m Bool :=
-  let rec @[specialize] loop : ∀ i, i ≤ n → m Bool
-    | 0,   _ => pure false
-    | i+1, h => do
-      match (← p (n-i-1) (by omega)) with
+@[inline] def anyM {m} [Monad m] (n : Nat) (p : Nat → m Bool) : m Bool :=
+  let rec @[specialize] loop
+    | 0   => pure false
+    | i+1 => do
+      match (← p (n-i-1)) with
       | true  => pure true
-      | false => loop i (Nat.le_of_succ_le h)
-  loop n (by simp)
+      | false => loop i
+  loop n
 
 end Nat

src/Init/Data/Nat/Dvd.lean

@@ -39,9 +39,9 @@ protected theorem dvd_add_iff_right {k m n : Nat} (h : k ∣ m) : k ∣ n ↔ k
 protected theorem dvd_add_iff_left {k m n : Nat} (h : k ∣ n) : k ∣ m ↔ k ∣ m + n := by
   rw [Nat.add_comm]; exact Nat.dvd_add_iff_right h
 
-theorem dvd_mod_iff {k m n : Nat} (h: k ∣ n) : k ∣ m % n ↔ k ∣ m := by
-  have := Nat.dvd_add_iff_left (m := m % n) <| Nat.dvd_trans h <| Nat.dvd_mul_right n (m / n)
-  rwa [mod_add_div] at this
+theorem dvd_mod_iff {k m n : Nat} (h: k ∣ n) : k ∣ m % n ↔ k ∣ m :=
+  have := Nat.dvd_add_iff_left <| Nat.dvd_trans h <| Nat.dvd_mul_right n (m / n)
+  by rwa [mod_add_div] at this
 
 theorem le_of_dvd {m n : Nat} (h : 0 < n) : m ∣ n → m ≤ n
   | ⟨k, e⟩ => by
@@ -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 := [2]) [← mod_add_div a b]
+  rw (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/Fold.lean

@@ -1,217 +0,0 @@
-/-
-Copyright (c) 2014 Microsoft Corporation. All rights reserved.
-Released under Apache 2.0 license as described in the file LICENSE.
-Authors: Floris van Doorn, Leonardo de Moura, Kim Morrison
--/
-prelude
-import Init.Omega
-import Init.Data.List.FinRange
-
-set_option linter.missingDocs true -- keep it documented
-universe u
-
-namespace Nat
-
-/--
-`Nat.fold` evaluates `f` on the numbers up to `n` exclusive, in increasing order:
-* `Nat.fold f 3 init = init |> f 0 |> f 1 |> f 2`
--/
-@[specialize] def fold {α : Type u} : (n : Nat) → (f : (i : Nat) → i < n → α → α) → (init : α) → α
-  | 0,      f, a => a
-  | succ n, f, a => f n (by omega) (fold n (fun i h => f i (by omega)) a)
-
-/-- Tail-recursive version of `Nat.fold`. -/
-@[inline] def foldTR {α : Type u} (n : Nat) (f : (i : Nat) → i < n → α → α) (init : α) : α :=
-  let rec @[specialize] loop : ∀ j, j ≤ n → α → α
-    | 0,      h, a => a
-    | succ m, h, a => loop m (by omega) (f (n - succ m) (by omega) a)
-  loop n (by omega) init
-
-/--
-`Nat.foldRev` evaluates `f` on the numbers up to `n` exclusive, in decreasing order:
-* `Nat.foldRev f 3 init = f 0 <| f 1 <| f 2 <| init`
--/
-@[specialize] def foldRev {α : Type u} : (n : Nat) → (f : (i : Nat) → i < n → α → α) → (init : α) → α
-  | 0,      f, a => a
-  | succ n, f, a => foldRev n (fun i h => f i (by omega)) (f n (by omega) a)
-
-/-- `any f n = true` iff there is `i in [0, n-1]` s.t. `f i = true` -/
-@[specialize] def any : (n : Nat) → (f : (i : Nat) → i < n → Bool) → Bool
-  | 0,      f => false
-  | succ n, f => any n (fun i h => f i (by omega)) || f n (by omega)
-
-/-- Tail-recursive version of `Nat.any`. -/
-@[inline] def anyTR (n : Nat) (f : (i : Nat) → i < n → Bool) : Bool :=
-  let rec @[specialize] loop : (i : Nat) → i ≤ n → Bool
-    | 0,      h => false
-    | succ m, h => f (n - succ m) (by omega) || loop m (by omega)
-  loop n (by omega)
-
-/-- `all f n = true` iff every `i in [0, n-1]` satisfies `f i = true` -/
-@[specialize] def all : (n : Nat) → (f : (i : Nat) → i < n → Bool) → Bool
-  | 0,      f => true
-  | succ n, f => all n (fun i h => f i (by omega)) && f n (by omega)
-
-/-- Tail-recursive version of `Nat.all`. -/
-@[inline] def allTR (n : Nat) (f : (i : Nat) → i < n → Bool) : Bool :=
-  let rec @[specialize] loop : (i : Nat) → i ≤ n   → Bool
-    | 0,      h => true
-    | succ m, h => f (n - succ m) (by omega) && loop m (by omega)
-  loop n (by omega)
-
-/-! # csimp theorems -/
-
-theorem fold_congr {α : Type u} {n m : Nat} (w : n = m)
-     (f : (i : Nat) → i < n → α → α) (init : α) :
-     fold n f init = fold m (fun i h => f i (by omega)) init := by
-  subst m
-  rfl
-
-theorem foldTR_loop_congr {α : Type u} {n m : Nat} (w : n = m)
-     (f : (i : Nat) → i < n → α → α) (j : Nat) (h : j ≤ n) (init : α) :
-     foldTR.loop n f j h init = foldTR.loop m (fun i h => f i (by omega)) j (by omega) init := by
-  subst m
-  rfl
-
-@[csimp] theorem fold_eq_foldTR : @fold = @foldTR :=
-  funext fun α => funext fun n => funext fun f => funext fun init =>
-  let rec go : ∀ m n f, fold (m + n) f init = foldTR.loop (m + n) f m (by omega) (fold n (fun i h => f i (by omega)) init)
-    | 0,      n, f => by
-      simp only [foldTR.loop]
-      have t : 0 + n = n := by omega
-      rw [fold_congr t]
-    | succ m, n, f => by
-      have t : (m + 1) + n = m + (n + 1) := by omega
-      rw [foldTR.loop]
-      simp only [succ_eq_add_one, Nat.add_sub_cancel]
-      rw [fold_congr t, foldTR_loop_congr t, go, fold]
-      congr
-      omega
-  go n 0 f
-
-theorem any_congr {n m : Nat} (w : n = m) (f : (i : Nat) → i < n → Bool) : any n f = any m (fun i h => f i (by omega)) := by
-  subst m
-  rfl
-
-theorem anyTR_loop_congr {n m : Nat} (w : n = m) (f : (i : Nat) → i < n → Bool) (j : Nat) (h : j ≤ n) :
-    anyTR.loop n f j h = anyTR.loop m (fun i h => f i (by omega)) j (by omega) := by
-  subst m
-  rfl
-
-@[csimp] theorem any_eq_anyTR : @any = @anyTR :=
-  funext fun n => funext fun f =>
-  let rec go : ∀ m n f, any (m + n) f = (any n (fun i h => f i (by omega)) || anyTR.loop (m + n) f m (by omega))
-    | 0,      n, f => by
-      simp [anyTR.loop]
-      have t : 0 + n = n := by omega
-      rw [any_congr t]
-    | succ m, n, f => by
-      have t : (m + 1) + n = m + (n + 1) := by omega
-      rw [anyTR.loop]
-      simp only [succ_eq_add_one]
-      rw [any_congr t, anyTR_loop_congr t, go, any, Bool.or_assoc]
-      congr
-      omega
-  go n 0 f
-
-theorem all_congr {n m : Nat} (w : n = m) (f : (i : Nat) → i < n → Bool) : all n f = all m (fun i h => f i (by omega)) := by
-  subst m
-  rfl
-
-theorem allTR_loop_congr {n m : Nat} (w : n = m) (f : (i : Nat) → i < n → Bool) (j : Nat) (h : j ≤ n) : allTR.loop n f j h = allTR.loop m (fun i h => f i (by omega)) j (by omega) := by
-  subst m
-  rfl
-
-@[csimp] theorem all_eq_allTR : @all = @allTR :=
-  funext fun n => funext fun f =>
-  let rec go : ∀ m n f, all (m + n) f = (all n (fun i h => f i (by omega)) && allTR.loop (m + n) f m (by omega))
-    | 0,      n, f => by
-      simp [allTR.loop]
-      have t : 0 + n = n := by omega
-      rw [all_congr t]
-    | succ m, n, f => by
-      have t : (m + 1) + n = m + (n + 1) := by omega
-      rw [allTR.loop]
-      simp only [succ_eq_add_one]
-      rw [all_congr t, allTR_loop_congr t, go, all, Bool.and_assoc]
-      congr
-      omega
-  go n 0 f
-
-@[simp] theorem fold_zero {α : Type u} (f : (i : Nat) → i < 0 → α → α) (init : α) :
-    fold 0 f init = init := by simp [fold]
-
-@[simp] theorem fold_succ {α : Type u} (n : Nat) (f : (i : Nat) → i < n + 1 → α → α) (init : α) :
-    fold (n + 1) f init = f n (by omega) (fold n (fun i h => f i (by omega)) init) := by simp [fold]
-
-theorem fold_eq_finRange_foldl {α : Type u} (n : Nat) (f : (i : Nat) → i < n → α → α) (init : α) :
-    fold n f init = (List.finRange n).foldl (fun acc ⟨i, h⟩ => f i h acc) init := by
-  induction n with
-  | zero => simp
-  | succ n ih =>
-    simp [ih, List.finRange_succ_last, List.foldl_map]
-
-@[simp] theorem foldRev_zero {α : Type u} (f : (i : Nat) → i < 0 → α → α) (init : α) :
-    foldRev 0 f init = init := by simp [foldRev]
-
-@[simp] theorem foldRev_succ {α : Type u} (n : Nat) (f : (i : Nat) → i < n + 1 → α → α) (init : α) :
-    foldRev (n + 1) f init = foldRev n (fun i h => f i (by omega)) (f n (by omega) init) := by
-  simp [foldRev]
-
-theorem foldRev_eq_finRange_foldr {α : Type u} (n : Nat) (f : (i : Nat) → i < n → α → α) (init : α) :
-    foldRev n f init = (List.finRange n).foldr (fun ⟨i, h⟩ acc => f i h acc) init := by
-  induction n generalizing init with
-  | zero => simp
-  | succ n ih => simp [ih, List.finRange_succ_last, List.foldr_map]
-
-@[simp] theorem any_zero {f : (i : Nat) → i < 0 → Bool} : any 0 f = false := by simp [any]
-
-@[simp] theorem any_succ {n : Nat} (f : (i : Nat) → i < n + 1 → Bool) :
-  any (n + 1) f = (any n (fun i h => f i (by omega)) || f n (by omega)) := by simp [any]
-
-theorem any_eq_finRange_any {n : Nat} (f : (i : Nat) → i < n → Bool) :
-    any n f = (List.finRange n).any (fun ⟨i, h⟩ => f i h) := by
-  induction n with
-  | zero => simp
-  | succ n ih => simp [ih, List.finRange_succ_last, List.any_map, Function.comp_def]
-
-@[simp] theorem all_zero {f : (i : Nat) → i < 0 → Bool} : all 0 f = true := by simp [all]
-
-@[simp] theorem all_succ {n : Nat} (f : (i : Nat) → i < n + 1 → Bool) :
-  all (n + 1) f = (all n (fun i h => f i (by omega)) && f n (by omega)) := by simp [all]
-
-theorem all_eq_finRange_all {n : Nat} (f : (i : Nat) → i < n → Bool) :
-    all n f = (List.finRange n).all (fun ⟨i, h⟩ => f i h) := by
-  induction n with
-  | zero => simp
-  | succ n ih => simp [ih, List.finRange_succ_last, List.all_map, Function.comp_def]
-
-end Nat
-
-namespace Prod
-
-/--
-`(start, stop).foldI f a` evaluates `f` on all the numbers
-from `start` (inclusive) to `stop` (exclusive) in increasing order:
-* `(5, 8).foldI f init = init |> f 5 |> f 6 |> f 7`
--/
-@[inline] def foldI {α : Type u} (i : Nat × Nat) (f : (j : Nat) → i.1 ≤ j → j < i.2 → α → α) (a : α) : α :=
-  (i.2 - i.1).fold (fun j _ => f (i.1 + j) (by omega) (by omega)) a
-
-/--
-`(start, stop).anyI f a` returns true if `f` is true for some natural number
-from `start` (inclusive) to `stop` (exclusive):
-* `(5, 8).anyI f = f 5 || f 6 || f 7`
--/
-@[inline] def anyI (i : Nat × Nat) (f : (j : Nat) → i.1 ≤ j → j < i.2 → Bool) : Bool :=
-  (i.2 - i.1).any (fun j _ => f (i.1 + j) (by omega) (by omega))
-
-/--
-`(start, stop).allI f a` returns true if `f` is true for all natural numbers
-from `start` (inclusive) to `stop` (exclusive):
-* `(5, 8).anyI f = f 5 && f 6 && f 7`
--/
-@[inline] def allI (i : Nat × Nat) (f : (j : Nat) → i.1 ≤ j → j < i.2 → Bool) : Bool :=
-  (i.2 - i.1).all (fun j _ => f (i.1 + j) (by omega) (by omega))
-
-end Prod

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 := [1]) [← mod_add_div a n]
-  rw (occs := [1]) [← mod_add_div b n]
+  rw (occs := .pos [1]) [← mod_add_div a n]
+  rw (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]
@@ -679,10 +679,6 @@ theorem add_mod (a b n : Nat) : (a + b) % n = ((a % n) + (b % n)) % n := by
 @[simp] theorem mod_mul_mod {a b c : Nat} : (a % c * b) % c = a * b % c := by
   rw [mul_mod, mod_mod, ← mul_mod]
 
-theorem mod_eq_sub (x w : Nat) : x % w = x - w * (x / w) := by
-  conv => rhs; congr; rw [← mod_add_div x w]
-  simp
-
 /-! ### pow -/
 
 theorem pow_succ' {m n : Nat} : m ^ n.succ = m * m ^ n := by
@@ -850,18 +846,6 @@ protected theorem pow_lt_pow_iff_pow_mul_le_pow {a n m : Nat} (h : 1 < a) :
   rw [←Nat.pow_add_one, Nat.pow_le_pow_iff_right (by omega), Nat.pow_lt_pow_iff_right (by omega)]
   omega
 
-protected theorem lt_pow_self {n a : Nat} (h : 1 < a) : n < a ^ n := by
-  induction n with
-  | zero => exact Nat.zero_lt_one
-  | succ _ ih => exact Nat.lt_of_lt_of_le (Nat.add_lt_add_right ih 1) (Nat.pow_lt_pow_succ h)
-
-protected theorem lt_two_pow_self : n < 2 ^ n :=
-  Nat.lt_pow_self Nat.one_lt_two
-
-@[simp]
-protected theorem mod_two_pow_self : n % 2 ^ n = n :=
-  Nat.mod_eq_of_lt Nat.lt_two_pow_self
-
 @[simp]
 theorem two_pow_pred_mul_two (h : 0 < w) :
     2 ^ (w - 1) * 2 = 2 ^ w := by
@@ -1046,25 +1030,6 @@ instance decidableExistsLE [DecidablePred p] : DecidablePred fun n => ∃ m : Na
   fun n => decidable_of_iff (∃ m, m < n + 1 ∧ p m)
     (exists_congr fun _ => and_congr_left' Nat.lt_succ_iff)
 
-/-- Dependent version of `decidableExistsLT`. -/
-instance decidableExistsLT' {p : (m : Nat) → m < k → Prop} [I : ∀ m h, Decidable (p m h)] :
-    Decidable (∃ m : Nat, ∃ h : m < k, p m h) :=
-  match k, p, I with
-  | 0, _, _ => isFalse (by simp)
-  | (k + 1), p, I => @decidable_of_iff _ ((∃ m, ∃ h : m < k, p m (by omega)) ∨ p k (by omega))
-      ⟨by rintro (⟨m, h, w⟩ | w); exact ⟨m, by omega, w⟩; exact ⟨k, by omega, w⟩,
-        fun ⟨m, h, w⟩ => if h' : m < k then .inl ⟨m, h', w⟩ else
-          by obtain rfl := (by omega : m = k); exact .inr w⟩
-      (@instDecidableOr _ _
-        (decidableExistsLT' (p := fun m h => p m (by omega)) (I := fun m h => I m (by omega)))
-        inferInstance)
-
-/-- Dependent version of `decidableExistsLE`. -/
-instance decidableExistsLE' {p : (m : Nat) → m ≤ k → Prop} [I : ∀ m h, Decidable (p m h)] :
-    Decidable (∃ m : Nat, ∃ h : m ≤ k, p m h) :=
-  decidable_of_iff (∃ m, ∃ h : m < k + 1, p m (by omega)) (exists_congr fun _ =>
-    ⟨fun ⟨h, w⟩ => ⟨le_of_lt_succ h, w⟩, fun ⟨h, w⟩ => ⟨lt_add_one_of_le h, w⟩⟩)
-
 /-! ### Results about `List.sum` specialized to `Nat` -/
 
 protected theorem sum_pos_iff_exists_pos {l : List Nat} : 0 < l.sum ↔ ∃ x ∈ l, 0 < x := by

src/Init/Data/NeZero.lean

@@ -36,7 +36,3 @@ theorem neZero_iff {n : R} : NeZero n ↔ n ≠ 0 :=
 
 @[simp] theorem neZero_zero_iff_false {α : Type _} [Zero α] : NeZero (0 : α) ↔ False :=
   ⟨fun _ ↦ NeZero.ne (0 : α) rfl, fun h ↦ h.elim⟩
-
-instance {p : Prop} [Decidable p] {n m : Nat} [NeZero n] [NeZero m] :
-    NeZero (if p then n else m) := by
-  split <;> infer_instance

src/Init/Data/Option.lean

@@ -10,4 +10,3 @@ import Init.Data.Option.Instances
 import Init.Data.Option.Lemmas
 import Init.Data.Option.Attach
 import Init.Data.Option.List
-import Init.Data.Option.Monadic

src/Init/Data/Option/Attach.lean

@@ -119,14 +119,10 @@ theorem attachWith_map_subtype_val {p : α → Prop} (o : Option α) (H : ∀ a
   · simp at h
   · simp [get_some]
 
-theorem toList_attach (o : Option α) :
+@[simp] theorem toList_attach (o : Option α) :
     o.attach.toList = o.toList.attach.map fun ⟨x, h⟩ => ⟨x, by simpa using h⟩ := by
   cases o <;> simp
 
-@[simp] theorem attach_toList (o : Option α) :
-    o.toList.attach = (o.attach.map fun ⟨a, h⟩ => ⟨a, by simpa using h⟩).toList := by
-  cases o <;> simp
-
 theorem attach_map {o : Option α} (f : α → β) :
     (o.map f).attach = o.attach.map (fun ⟨x, h⟩ => ⟨f x, mem_map_of_mem f h⟩) := by
   cases o <;> simp

src/Init/Data/Option/Instances.lean

@@ -70,13 +70,6 @@ satisfy `p`, using the proof to apply `f`.
   | none, _ => none
   | some a, H => f a (H a rfl)
 
-/-- Partial elimination. If `o : Option α` and `f : (a : α) → a ∈ o → β`, then `o.pelim b f` is
-the same as `o.elim b f` but `f` is passed the proof that `a ∈ o`. -/
-@[inline] def pelim (o : Option α) (b : β) (f : (a : α) → a ∈ o → β) : β :=
-  match o with
-  | none => b
-  | some a => f a rfl
-
 /-- Map a monadic function which returns `Unit` over an `Option`. -/
 @[inline] protected def forM [Pure m] : Option α → (α → m PUnit) → m PUnit
   | none  , _ => pure ⟨⟩

src/Init/Data/Option/Lemmas.lean

@@ -629,12 +629,4 @@ theorem pbind_eq_some_iff {o : Option α} {f : (a : α) → a ∈ o → Option
     · rintro ⟨h, rfl⟩
       rfl
 
-/-! ### pelim -/
-
-@[simp] theorem pelim_none : pelim none b f = b := rfl
-@[simp] theorem pelim_some : pelim (some a) b f = f a rfl := rfl
-
-@[simp] theorem pelim_eq_elim : pelim o b (fun a _ => f a) = o.elim b f := by
-  cases o <;> simp
-
 end Option

src/Init/Data/Option/List.lean

@@ -15,25 +15,17 @@ namespace Option
     forIn' none b f = pure b := by
   rfl
 
-@[simp] theorem forIn'_some [Monad m] [LawfulMonad m] (a : α) (b : β) (f : (a' : α) → a' ∈ some a → β → m (ForInStep β)) :
-    forIn' (some a) b f = bind (f a rfl b) (fun r => pure (ForInStep.value r)) := by
-  simp only [forIn', bind_pure_comp]
-  rw [map_eq_pure_bind]
-  congr
-  funext x
-  split <;> rfl
+@[simp] theorem forIn'_some [Monad m] (a : α) (b : β) (f : (a' : α) → a' ∈ some a → β → m (ForInStep β)) :
+    forIn' (some a) b f = bind (f a rfl b) (fun | .done r | .yield r => pure r) := by
+  rfl
 
 @[simp] theorem forIn_none [Monad m] (b : β) (f : α → β → m (ForInStep β)) :
     forIn none b f = pure b := by
   rfl
 
-@[simp] theorem forIn_some [Monad m] [LawfulMonad m] (a : α) (b : β) (f : α → β → m (ForInStep β)) :
-    forIn (some a) b f = bind (f a b) (fun r => pure (ForInStep.value r)) := by
-  simp only [forIn, forIn', bind_pure_comp]
-  rw [map_eq_pure_bind]
-  congr
-  funext x
-  split <;> rfl
+@[simp] theorem forIn_some [Monad m] (a : α) (b : β) (f : α → β → m (ForInStep β)) :
+    forIn (some a) b f = bind (f a b) (fun | .done r | .yield r => pure r) := by
+  rfl
 
 @[simp] theorem forIn'_toList [Monad m] (o : Option α) (b : β) (f : (a : α) → a ∈ o.toList → β → m (ForInStep β)) :
     forIn' o.toList b f = forIn' o b fun a m b => f a (by simpa using m) b := by
@@ -43,20 +35,4 @@ namespace Option
     forIn o.toList b f = forIn o b f := by
   cases o <;> rfl
 
-@[simp] theorem foldlM_toList [Monad m] [LawfulMonad m] (o : Option β) (a : α) (f : α → β → m α) :
-    o.toList.foldlM f a = o.elim (pure a) (fun b => f a b) := by
-  cases o <;> simp
-
-@[simp] theorem foldrM_toList [Monad m] [LawfulMonad m] (o : Option β) (a : α) (f : β → α → m α) :
-    o.toList.foldrM f a = o.elim (pure a) (fun b => f b a) := by
-  cases o <;> simp
-
-@[simp] theorem foldl_toList (o : Option β) (a : α) (f : α → β → α) :
-    o.toList.foldl f a = o.elim a (fun b => f a b) := by
-  cases o <;> simp
-
-@[simp] theorem foldr_toList (o : Option β) (a : α) (f : β → α → α) :
-    o.toList.foldr f a = o.elim a (fun b => f b a) := by
-  cases o <;> simp
-
 end Option

src/Init/Data/Option/Monadic.lean

@@ -1,75 +0,0 @@
-/-
-Copyright (c) 2024 Lean FRO. All rights reserved.
-Released under Apache 2.0 license as described in the file LICENSE.
-Authors: Kim Morrison
--/
-prelude
-
-import Init.Data.Option.Attach
-import Init.Control.Lawful.Basic
-
-namespace Option
-
-@[congr] theorem forIn'_congr [Monad m] [LawfulMonad m]{as bs : Option α} (w : as = bs)
-    {b b' : β} (hb : b = b')
-    {f : (a' : α) → a' ∈ as → β → m (ForInStep β)}
-    {g : (a' : α) → a' ∈ bs → β → m (ForInStep β)}
-    (h : ∀ a m b, f a (by simpa [w] using m) b = g a m b) :
-    forIn' as b f = forIn' bs b' g := by
-  cases as <;> cases bs
-  · simp [hb]
-  · simp at w
-  · simp at w
-  · simp only [some.injEq] at w
-    subst w
-    simp [hb, h]
-
-theorem forIn'_eq_pelim [Monad m] [LawfulMonad m]
-    (o : Option α) (f : (a : α) → a ∈ o → β → m (ForInStep β)) (b : β) :
-    forIn' o b f =
-      o.pelim (pure b) (fun a h => ForInStep.value <$> f a h b) := by
-  cases o <;> simp
-
-@[simp] theorem forIn'_yield_eq_pelim [Monad m] [LawfulMonad m] (o : Option α)
-    (f : (a : α) → a ∈ o → β → m γ) (g : (a : α) → a ∈ o → β → γ → β) (b : β) :
-    forIn' o b (fun a m b => (fun c => .yield (g a m b c)) <$> f a m b) =
-      o.pelim (pure b) (fun a h => g a h b <$> f a h b) := by
-  cases o <;> simp
-
-theorem forIn'_pure_yield_eq_pelim [Monad m] [LawfulMonad m]
-    (o : Option α) (f : (a : α) → a ∈ o → β → β) (b : β) :
-    forIn' o b (fun a m b => pure (.yield (f a m b))) =
-      pure (f := m) (o.pelim b (fun a h => f a h b)) := by
-  cases o <;> simp
-
-@[simp] theorem forIn'_id_yield_eq_pelim
-    (o : Option α) (f : (a : α) → a ∈ o → β → β) (b : β) :
-    forIn' (m := Id) o b (fun a m b => .yield (f a m b)) =
-      o.pelim b (fun a h => f a h b) := by
-  cases o <;> simp
-
-theorem forIn_eq_elim [Monad m] [LawfulMonad m]
-    (o : Option α) (f : (a : α) → β → m (ForInStep β)) (b : β) :
-    forIn o b f =
-      o.elim (pure b) (fun a => ForInStep.value <$> f a b) := by
-  cases o <;> simp
-
-@[simp] theorem forIn_yield_eq_elim [Monad m] [LawfulMonad m] (o : Option α)
-    (f : (a : α) → β → m γ) (g : (a : α) → β → γ → β) (b : β) :
-    forIn o b (fun a b => (fun c => .yield (g a b c)) <$> f a b) =
-      o.elim (pure b) (fun a => g a b <$> f a b) := by
-  cases o <;> simp
-
-theorem forIn_pure_yield_eq_elim [Monad m] [LawfulMonad m]
-    (o : Option α) (f : (a : α) → β → β) (b : β) :
-    forIn o b (fun a b => pure (.yield (f a b))) =
-      pure (f := m) (o.elim b (fun a => f a b)) := by
-  cases o <;> simp
-
-@[simp] theorem forIn_id_yield_eq_elim
-    (o : Option α) (f : (a : α) → β → β) (b : β) :
-    forIn (m := Id) o b (fun a b => .yield (f a b)) =
-      o.elim b (fun a => f a b) := by
-  cases o <;> simp
-
-end Option

src/Init/Data/Random.lean

@@ -113,10 +113,10 @@ initialize IO.stdGenRef : IO.Ref StdGen ←
   let seed := UInt64.toNat (ByteArray.toUInt64LE! (← IO.getRandomBytes 8))
   IO.mkRef (mkStdGen seed)
 
-def IO.setRandSeed (n : Nat) : BaseIO Unit :=
+def IO.setRandSeed (n : Nat) : IO Unit :=
   IO.stdGenRef.set (mkStdGen n)
 
-def IO.rand (lo hi : Nat) : BaseIO Nat := do
+def IO.rand (lo hi : Nat) : IO Nat := do
   let gen ← IO.stdGenRef.get
   let (r, gen) := randNat gen lo hi
   IO.stdGenRef.set gen

src/Init/Data/Sum/Basic.lean

@@ -31,7 +31,7 @@ This file defines basic operations on the the sum type `α ⊕ β`.
 
 ## Further material
 
-See `Init.Data.Sum.Lemmas` for theorems about these definitions.
+See `Batteries.Data.Sum.Lemmas` for theorems about these definitions.
 
 ## Notes
 

src/Init/Data/UInt/Basic.lean

@@ -246,12 +246,6 @@ instance (a b : UInt64) : Decidable (a ≤ b) := UInt64.decLe a b
 instance : Max UInt64 := maxOfLe
 instance : Min UInt64 := minOfLe
 
-theorem usize_size_le : USize.size ≤ 18446744073709551616 := by
-  cases usize_size_eq <;> next h => rw [h]; decide
-
-theorem le_usize_size : 4294967296 ≤ USize.size := by
-  cases usize_size_eq <;> next h => rw [h]; decide
-
 @[extern "lean_usize_mul"]
 def USize.mul (a b : USize) : USize := ⟨a.toBitVec * b.toBitVec⟩
 @[extern "lean_usize_div"]
@@ -270,39 +264,10 @@ def USize.xor (a b : USize) : USize := ⟨a.toBitVec ^^^ b.toBitVec⟩
 def USize.shiftLeft (a b : USize) : USize := ⟨a.toBitVec <<< (mod b (USize.ofNat System.Platform.numBits)).toBitVec⟩
 @[extern "lean_usize_shift_right"]
 def USize.shiftRight (a b : USize) : USize := ⟨a.toBitVec >>> (mod b (USize.ofNat System.Platform.numBits)).toBitVec⟩
-/--
-Upcast a `Nat` less than `2^32` to a `USize`.
-This is lossless because `USize.size` is either `2^32` or `2^64`.
-This function is overridden with a native implementation.
--/
-@[extern "lean_usize_of_nat"]
-def USize.ofNat32 (n : @& Nat) (h : n < 4294967296) : USize :=
-  USize.ofNatCore n (Nat.lt_of_lt_of_le h le_usize_size)
-@[extern "lean_uint8_to_usize"]
-def UInt8.toUSize (a : UInt8) : USize :=
-  USize.ofNat32 a.toBitVec.toNat (Nat.lt_trans a.toBitVec.isLt (by decide))
-@[extern "lean_usize_to_uint8"]
-def USize.toUInt8 (a : USize) : UInt8 := a.toNat.toUInt8
-@[extern "lean_uint16_to_usize"]
-def UInt16.toUSize (a : UInt16) : USize :=
-  USize.ofNat32 a.toBitVec.toNat (Nat.lt_trans a.toBitVec.isLt (by decide))
-@[extern "lean_usize_to_uint16"]
-def USize.toUInt16 (a : USize) : UInt16 := a.toNat.toUInt16
 @[extern "lean_uint32_to_usize"]
 def UInt32.toUSize (a : UInt32) : USize := USize.ofNat32 a.toBitVec.toNat a.toBitVec.isLt
 @[extern "lean_usize_to_uint32"]
 def USize.toUInt32 (a : USize) : UInt32 := a.toNat.toUInt32
-/-- Converts a `UInt64` to a `USize` by reducing modulo `USize.size`. -/
-@[extern "lean_uint64_to_usize"]
-def UInt64.toUSize (a : UInt64) : USize := a.toNat.toUSize
-/--
-Upcast a `USize` to a `UInt64`.
-This is lossless because `USize.size` is either `2^32` or `2^64`.
-This function is overridden with a native implementation.
--/
-@[extern "lean_usize_to_uint64"]
-def USize.toUInt64 (a : USize) : UInt64 :=
-  UInt64.ofNatCore a.toBitVec.toNat (Nat.lt_of_lt_of_le a.toBitVec.isLt usize_size_le)
 
 instance : Mul USize       := ⟨USize.mul⟩
 instance : Mod USize       := ⟨USize.mod⟩

src/Init/Data/UInt/BasicAux.lean

@@ -94,8 +94,10 @@ def UInt32.toUInt64 (a : UInt32) : UInt64 := ⟨⟨a.toNat, Nat.lt_trans a.toBit
 
 instance UInt64.instOfNat : OfNat UInt64 n := ⟨UInt64.ofNat n⟩
 
-@[deprecated usize_size_pos (since := "2024-11-24")] theorem usize_size_gt_zero : USize.size > 0 :=
-  usize_size_pos
+theorem usize_size_gt_zero : USize.size > 0 := by
+  cases usize_size_eq with
+  | inl h => rw [h]; decide
+  | inr h => rw [h]; decide
 
 def USize.val (x : USize) : Fin USize.size := x.toBitVec.toFin
 @[extern "lean_usize_of_nat"]

src/Init/Data/UInt/Bitwise.lean

@@ -1,39 +1,25 @@
 /-
 Copyright (c) 2024 Lean FRO, LLC. All Rights Reserved.
 Released under Apache 2.0 license as described in the file LICENSE.
-Authors: Markus Himmel, Mac Malone
+Authors: Markus Himmel
 -/
 prelude
-import Init.Data.UInt.Lemmas
+import Init.Data.UInt.Basic
 import Init.Data.Fin.Bitwise
 import Init.Data.BitVec.Lemmas
 
 set_option hygiene false in
-macro "declare_bitwise_uint_theorems" typeName:ident bits:term:arg : command =>
+macro "declare_bitwise_uint_theorems" typeName:ident : command =>
 `(
 namespace $typeName
 
-@[simp] protected theorem toBitVec_and (a b : $typeName) : (a &&& b).toBitVec = a.toBitVec &&& b.toBitVec := rfl
-@[simp] protected theorem toBitVec_or (a b : $typeName) : (a ||| b).toBitVec = a.toBitVec ||| b.toBitVec := rfl
-@[simp] protected theorem toBitVec_xor (a b : $typeName) : (a ^^^ b).toBitVec = a.toBitVec ^^^ b.toBitVec := rfl
-@[simp] protected theorem toBitVec_shiftLeft (a b : $typeName) : (a <<< b).toBitVec = a.toBitVec <<< (b.toBitVec % $bits) := rfl
-@[simp] protected theorem toBitVec_shiftRight (a b : $typeName) : (a >>> b).toBitVec = a.toBitVec >>> (b.toBitVec % $bits) := rfl
-
-@[simp] protected theorem toNat_and (a b : $typeName) : (a &&& b).toNat = a.toNat &&& b.toNat := by simp [toNat]
-@[simp] protected theorem toNat_or (a b : $typeName) : (a ||| b).toNat = a.toNat ||| b.toNat := by simp [toNat]
-@[simp] protected theorem toNat_xor (a b : $typeName) : (a ^^^ b).toNat = a.toNat ^^^ b.toNat := by simp [toNat]
-@[simp] protected theorem toNat_shiftLeft (a b : $typeName) : (a <<< b).toNat = a.toNat <<< (b.toNat % $bits) % 2 ^ $bits := by simp [toNat]
-@[simp] protected theorem toNat_shiftRight (a b : $typeName) : (a >>> b).toNat = a.toNat >>> (b.toNat % $bits) := by simp [toNat]
-
-open $typeName (toNat_and) in
-@[deprecated toNat_and (since := "2024-11-28")]
-protected theorem and_toNat (a b : $typeName) : (a &&& b).toNat = a.toNat &&& b.toNat := BitVec.toNat_and ..
+@[simp] protected theorem and_toNat (a b : $typeName) : (a &&& b).toNat = a.toNat &&& b.toNat := BitVec.toNat_and ..
 
 end $typeName
 )
 
-declare_bitwise_uint_theorems UInt8 8
-declare_bitwise_uint_theorems UInt16 16
-declare_bitwise_uint_theorems UInt32 32
-declare_bitwise_uint_theorems UInt64 64
-declare_bitwise_uint_theorems USize System.Platform.numBits
+declare_bitwise_uint_theorems UInt8
+declare_bitwise_uint_theorems UInt16
+declare_bitwise_uint_theorems UInt32
+declare_bitwise_uint_theorems UInt64
+declare_bitwise_uint_theorems USize

src/Init/Data/UInt/Lemmas.lean

@@ -1,7 +1,7 @@
 /-
 Copyright (c) 2024 Amazon.com, Inc. or its affiliates. All Rights Reserved.
 Released under Apache 2.0 license as described in the file LICENSE.
-Authors: Leonardo de Moura, François G. Dorais, Mario Carneiro, Mac Malone
+Authors: Leonardo de Moura
 -/
 prelude
 import Init.Data.UInt.Basic
@@ -9,205 +9,129 @@ import Init.Data.Fin.Lemmas
 import Init.Data.BitVec.Lemmas
 import Init.Data.BitVec.Bitblast
 
-open Lean in
 set_option hygiene false in
-macro "declare_uint_theorems" typeName:ident bits:term:arg : command => do
-  let mut cmds ← Syntax.getArgs <$> `(
-  namespace $typeName
+macro "declare_uint_theorems" typeName:ident : command =>
+`(
+namespace $typeName
 
-  theorem zero_def : (0 : $typeName) = ⟨0⟩ := rfl
-  theorem one_def : (1 : $typeName) = ⟨1⟩ := rfl
-  theorem sub_def (a b : $typeName) : a - b = ⟨a.toBitVec - b.toBitVec⟩ := rfl
-  theorem mul_def (a b : $typeName) : a * b = ⟨a.toBitVec * b.toBitVec⟩ := rfl
-  theorem mod_def (a b : $typeName) : a % b = ⟨a.toBitVec % b.toBitVec⟩ := rfl
-  theorem add_def (a b : $typeName) : a + b = ⟨a.toBitVec + b.toBitVec⟩ := rfl
+instance : Inhabited $typeName where
+  default := 0
 
-  @[simp] theorem toNat_mk : (mk a).toNat = a.toNat := rfl
+theorem zero_def : (0 : $typeName) = ⟨0⟩ := rfl
+theorem one_def : (1 : $typeName) = ⟨1⟩ := rfl
+theorem sub_def (a b : $typeName) : a - b = ⟨a.toBitVec - b.toBitVec⟩ := rfl
+theorem mul_def (a b : $typeName) : a * b = ⟨a.toBitVec * b.toBitVec⟩ := rfl
+theorem mod_def (a b : $typeName) : a % b = ⟨a.toBitVec % b.toBitVec⟩ := rfl
+theorem add_def (a b : $typeName) : a + b = ⟨a.toBitVec + b.toBitVec⟩ := rfl
 
-  @[simp] theorem toNat_ofNat {n : Nat} : (ofNat n).toNat = n % 2 ^ $bits := BitVec.toNat_ofNat ..
+@[simp] theorem mk_toBitVec_eq : ∀ (a : $typeName), mk a.toBitVec = a
+  | ⟨_, _⟩ => rfl
 
-  @[simp] theorem toNat_ofNatCore {n : Nat} {h : n < size} : (ofNatCore n h).toNat = n := BitVec.toNat_ofNatLt ..
+theorem toBitVec_eq_of_lt {a : Nat} : a < size → (ofNat a).toBitVec.toNat = a :=
+  Nat.mod_eq_of_lt
 
-  @[simp] theorem val_val_eq_toNat (x : $typeName) : x.val.val = x.toNat := rfl
+theorem toNat_ofNat_of_lt {n : Nat} (h : n < size) : (ofNat n).toNat = n := by
+  rw [toNat, toBitVec_eq_of_lt h]
 
-  theorem toNat_toBitVec_eq_toNat (x : $typeName) : x.toBitVec.toNat = x.toNat := rfl
+theorem le_def {a b : $typeName} : a ≤ b ↔ a.toBitVec ≤ b.toBitVec := .rfl
 
-  @[simp] theorem mk_toBitVec_eq : ∀ (a : $typeName), mk a.toBitVec = a
-    | ⟨_, _⟩ => rfl
+theorem lt_def {a b : $typeName} : a < b ↔ a.toBitVec < b.toBitVec := .rfl
 
-  theorem toBitVec_eq_of_lt {a : Nat} : a < size → (ofNat a).toBitVec.toNat = a :=
-    Nat.mod_eq_of_lt
+@[simp] protected theorem not_le {a b : $typeName} : ¬ a ≤ b ↔ b < a := by simp [le_def, lt_def]
 
-  theorem toNat_ofNat_of_lt {n : Nat} (h : n < size) : (ofNat n).toNat = n := by
-    rw [toNat, toBitVec_eq_of_lt h]
+@[simp] protected theorem not_lt {a b : $typeName} : ¬ a < b ↔ b ≤ a := by simp [le_def, lt_def]
 
-  theorem le_def {a b : $typeName} : a ≤ b ↔ a.toBitVec ≤ b.toBitVec := .rfl
+@[simp] protected theorem le_refl (a : $typeName) : a ≤ a := by simp [le_def]
 
-  theorem lt_def {a b : $typeName} : a < b ↔ a.toBitVec < b.toBitVec := .rfl
+@[simp] protected theorem lt_irrefl (a : $typeName) : ¬ a < a := by simp
 
-  theorem le_iff_toNat_le {a b : $typeName} : a ≤ b ↔ a.toNat ≤ b.toNat := .rfl
+protected theorem le_trans {a b c : $typeName} : a ≤ b → b ≤ c → a ≤ c := BitVec.le_trans
 
-  theorem lt_iff_toNat_lt {a b : $typeName} : a < b ↔ a.toNat < b.toNat := .rfl
+protected theorem lt_trans {a b c : $typeName} : a < b → b < c → a < c := BitVec.lt_trans
 
-  @[simp] protected theorem not_le {a b : $typeName} : ¬ a ≤ b ↔ b < a := by simp [le_def, lt_def]
+protected theorem le_total (a b : $typeName) : a ≤ b ∨ b ≤ a := BitVec.le_total ..
 
-  @[simp] protected theorem not_lt {a b : $typeName} : ¬ a < b ↔ b ≤ a := by simp [le_def, lt_def]
+protected theorem lt_asymm {a b : $typeName} : a < b → ¬ b < a := BitVec.lt_asymm
 
-  @[simp] protected theorem le_refl (a : $typeName) : a ≤ a := by simp [le_def]
+protected theorem toBitVec_eq_of_eq {a b : $typeName} (h : a = b) : a.toBitVec = b.toBitVec := h ▸ rfl
 
-  @[simp] protected theorem lt_irrefl (a : $typeName) : ¬ a < a := by simp
+protected theorem eq_of_toBitVec_eq {a b : $typeName} (h : a.toBitVec = b.toBitVec) : a = b := by
+  cases a; cases b; simp_all
 
-  protected theorem le_trans {a b c : $typeName} : a ≤ b → b ≤ c → a ≤ c := BitVec.le_trans
+open $typeName (eq_of_toBitVec_eq) in
+protected theorem eq_of_val_eq {a b : $typeName} (h : a.val = b.val) : a = b := by
+  rcases a with ⟨⟨_⟩⟩; rcases b with ⟨⟨_⟩⟩; simp_all [val]
 
-  protected theorem lt_trans {a b c : $typeName} : a < b → b < c → a < c := BitVec.lt_trans
+open $typeName (toBitVec_eq_of_eq) in
+protected theorem ne_of_toBitVec_ne {a b : $typeName} (h : a.toBitVec ≠ b.toBitVec) : a ≠ b :=
+  fun h' => absurd (toBitVec_eq_of_eq h') h
 
-  protected theorem le_total (a b : $typeName) : a ≤ b ∨ b ≤ a := BitVec.le_total ..
+open $typeName (ne_of_toBitVec_ne) in
+protected theorem ne_of_lt {a b : $typeName} (h : a < b) : a ≠ b := by
+  apply ne_of_toBitVec_ne
+  apply BitVec.ne_of_lt
+  simpa [lt_def] using h
 
-  protected theorem lt_asymm {a b : $typeName} : a < b → ¬ b < a := BitVec.lt_asymm
+@[simp] protected theorem toNat_zero : (0 : $typeName).toNat = 0 := Nat.zero_mod _
 
-  protected theorem toBitVec_eq_of_eq {a b : $typeName} (h : a = b) : a.toBitVec = b.toBitVec := h ▸ rfl
+@[simp] protected theorem toNat_mod (a b : $typeName) : (a % b).toNat = a.toNat % b.toNat := BitVec.toNat_umod ..
 
-  protected theorem eq_of_toBitVec_eq {a b : $typeName} (h : a.toBitVec = b.toBitVec) : a = b := by
-    cases a; cases b; simp_all
+@[simp] protected theorem toNat_div (a b : $typeName) : (a / b).toNat = a.toNat / b.toNat := BitVec.toNat_udiv  ..
 
-  open $typeName (eq_of_toBitVec_eq toBitVec_eq_of_eq) in
-  protected theorem toBitVec_inj {a b : $typeName} : a.toBitVec = b.toBitVec ↔ a = b :=
-    Iff.intro eq_of_toBitVec_eq toBitVec_eq_of_eq
+@[simp] protected theorem toNat_sub_of_le (a b : $typeName) : b ≤ a → (a - b).toNat = a.toNat - b.toNat := BitVec.toNat_sub_of_le
 
-  open $typeName (eq_of_toBitVec_eq) in
-  protected theorem eq_of_val_eq {a b : $typeName} (h : a.val = b.val) : a = b := by
-    rcases a with ⟨⟨_⟩⟩; rcases b with ⟨⟨_⟩⟩; simp_all [val]
+protected theorem toNat_lt_size (a : $typeName) : a.toNat < size := a.toBitVec.isLt
 
-  open $typeName (eq_of_val_eq) in
-  protected theorem val_inj {a b : $typeName} : a.val = b.val ↔ a = b :=
-    Iff.intro eq_of_val_eq (congrArg val)
+open $typeName (toNat_mod toNat_lt_size) in
+protected theorem toNat_mod_lt {m : Nat} : ∀ (u : $typeName), m > 0 → toNat (u % ofNat m) < m := by
+  intro u h1
+  by_cases h2 : m < size
+  · rw [toNat_mod, toNat_ofNat_of_lt h2]
+    apply Nat.mod_lt _ h1
+  · apply Nat.lt_of_lt_of_le
+    · apply toNat_lt_size
+    · simpa using h2
 
-  open $typeName (toBitVec_eq_of_eq) in
-  protected theorem ne_of_toBitVec_ne {a b : $typeName} (h : a.toBitVec ≠ b.toBitVec) : a ≠ b :=
-    fun h' => absurd (toBitVec_eq_of_eq h') h
+open $typeName (toNat_mod_lt) in
+set_option linter.deprecated false in
+@[deprecated toNat_mod_lt (since := "2024-09-24")]
+protected theorem modn_lt {m : Nat} : ∀ (u : $typeName), m > 0 → toNat (u % m) < m := by
+  intro u
+  simp only [(· % ·)]
+  simp only [gt_iff_lt, toNat, modn, Fin.modn_val, BitVec.natCast_eq_ofNat, BitVec.toNat_ofNat,
+    Nat.reducePow]
+  rw [Nat.mod_eq_of_lt]
+  · apply Nat.mod_lt
+  · apply Nat.lt_of_le_of_lt
+    · apply Nat.mod_le
+    · apply Fin.is_lt
 
-  open $typeName (ne_of_toBitVec_ne) in
-  protected theorem ne_of_lt {a b : $typeName} (h : a < b) : a ≠ b := by
-    apply ne_of_toBitVec_ne
-    apply BitVec.ne_of_lt
-    simpa [lt_def] using h
+protected theorem mod_lt (a : $typeName) {b : $typeName} : 0 < b → a % b < b := by
+  simp only [lt_def, mod_def]
+  apply BitVec.umod_lt
 
-  @[simp] protected theorem toNat_zero : (0 : $typeName).toNat = 0 := Nat.zero_mod _
+protected theorem toNat.inj : ∀ {a b : $typeName}, a.toNat = b.toNat → a = b
+  | ⟨_, _⟩, ⟨_, _⟩, rfl => rfl
 
-  @[simp] protected theorem toNat_add (a b : $typeName) : (a + b).toNat = (a.toNat + b.toNat) % 2 ^ $bits := BitVec.toNat_add ..
+@[simp] protected theorem ofNat_one : ofNat 1 = 1 := rfl
 
-  protected theorem toNat_sub (a b : $typeName) : (a - b).toNat = (2 ^ $bits - b.toNat + a.toNat) % 2 ^ $bits := BitVec.toNat_sub  ..
+@[simp]
+theorem val_ofNat (n : Nat) : val (no_index (OfNat.ofNat n)) = OfNat.ofNat n := rfl
 
-  @[simp] protected theorem toNat_mul (a b : $typeName) : (a * b).toNat = a.toNat * b.toNat % 2 ^ $bits := BitVec.toNat_mul  ..
+@[simp]
+theorem toBitVec_ofNat (n : Nat) : toBitVec (no_index (OfNat.ofNat n)) = BitVec.ofNat _ n := rfl
 
-  @[simp] protected theorem toNat_mod (a b : $typeName) : (a % b).toNat = a.toNat % b.toNat := BitVec.toNat_umod ..
+@[simp]
+theorem mk_ofNat (n : Nat) : mk (BitVec.ofNat _ n) = OfNat.ofNat n := rfl
 
-  @[simp] protected theorem toNat_div (a b : $typeName) : (a / b).toNat = a.toNat / b.toNat := BitVec.toNat_udiv  ..
+end $typeName
+)
 
-  @[simp] protected theorem toNat_sub_of_le (a b : $typeName) : b ≤ a → (a - b).toNat = a.toNat - b.toNat := BitVec.toNat_sub_of_le
-
-  protected theorem toNat_lt_size (a : $typeName) : a.toNat < size := a.toBitVec.isLt
-
-  open $typeName (toNat_mod toNat_lt_size) in
-  protected theorem toNat_mod_lt {m : Nat} : ∀ (u : $typeName), m > 0 → toNat (u % ofNat m) < m := by
-    intro u h1
-    by_cases h2 : m < size
-    · rw [toNat_mod, toNat_ofNat_of_lt h2]
-      apply Nat.mod_lt _ h1
-    · apply Nat.lt_of_lt_of_le
-      · apply toNat_lt_size
-      · simpa using h2
-
-  open $typeName (toNat_mod_lt) in
-  set_option linter.deprecated false in
-  @[deprecated toNat_mod_lt (since := "2024-09-24")]
-  protected theorem modn_lt {m : Nat} : ∀ (u : $typeName), m > 0 → toNat (u % m) < m := by
-    intro u
-    simp only [(· % ·)]
-    simp only [gt_iff_lt, toNat, modn, Fin.modn_val, BitVec.natCast_eq_ofNat, BitVec.toNat_ofNat,
-      Nat.reducePow]
-    rw [Nat.mod_eq_of_lt]
-    · apply Nat.mod_lt
-    · apply Nat.lt_of_le_of_lt
-      · apply Nat.mod_le
-      · apply Fin.is_lt
-
-  protected theorem mod_lt (a : $typeName) {b : $typeName} : 0 < b → a % b < b := by
-    simp only [lt_def, mod_def]
-    apply BitVec.umod_lt
-
-  protected theorem toNat.inj : ∀ {a b : $typeName}, a.toNat = b.toNat → a = b
-    | ⟨_, _⟩, ⟨_, _⟩, rfl => rfl
-
-  protected theorem toNat_inj : ∀ {a b : $typeName}, a.toNat = b.toNat ↔ a = b :=
-    Iff.intro toNat.inj (congrArg toNat)
-
-  open $typeName (toNat_inj) in
-  protected theorem le_antisymm_iff {a b : $typeName} : a = b ↔ a ≤ b ∧ b ≤ a :=
-    toNat_inj.symm.trans Nat.le_antisymm_iff
-
-  open $typeName (le_antisymm_iff) in
-  protected theorem le_antisymm {a b : $typeName} (h₁ : a ≤ b) (h₂ : b ≤ a) : a = b :=
-    le_antisymm_iff.2 ⟨h₁, h₂⟩
-
-  @[simp] protected theorem ofNat_one : ofNat 1 = 1 := rfl
-
-  @[simp] protected theorem ofNat_toNat {x : $typeName} : ofNat x.toNat = x := by
-    apply toNat.inj
-    simp [Nat.mod_eq_of_lt x.toNat_lt_size]
-
-  @[simp]
-  theorem val_ofNat (n : Nat) : val (no_index (OfNat.ofNat n)) = OfNat.ofNat n := rfl
-
-  @[simp]
-  theorem toBitVec_ofNat (n : Nat) : toBitVec (no_index (OfNat.ofNat n)) = BitVec.ofNat _ n := rfl
-
-  @[simp]
-  theorem mk_ofNat (n : Nat) : mk (BitVec.ofNat _ n) = OfNat.ofNat n := rfl
-
-  )
-  if let some nbits := bits.raw.isNatLit? then
-    if nbits > 8 then
-      cmds := cmds.push <| ←
-        `(@[simp] theorem toNat_toUInt8 (x : $typeName) : x.toUInt8.toNat = x.toNat % 2 ^ 8 := rfl)
-    if nbits < 16 then
-      cmds := cmds.push <| ←
-        `(@[simp] theorem toNat_toUInt16 (x : $typeName) : x.toUInt16.toNat = x.toNat := rfl)
-    else if nbits > 16 then
-      cmds := cmds.push <| ←
-        `(@[simp] theorem toNat_toUInt16 (x : $typeName) : x.toUInt16.toNat = x.toNat % 2 ^ 16 := rfl)
-    if nbits < 32 then
-      cmds := cmds.push <| ←
-        `(@[simp] theorem toNat_toUInt32 (x : $typeName) : x.toUInt32.toNat = x.toNat := rfl)
-    else if nbits > 32 then
-      cmds := cmds.push <| ←
-        `(@[simp] theorem toNat_toUInt32 (x : $typeName) : x.toUInt32.toNat = x.toNat % 2 ^ 32 := rfl)
-    if nbits ≤ 32 then
-      cmds := cmds.push <| ←
-        `(@[simp] theorem toNat_toUSize (x : $typeName) : x.toUSize.toNat = x.toNat := rfl)
-    else
-      cmds := cmds.push <| ←
-        `(@[simp] theorem toNat_toUSize (x : $typeName) : x.toUSize.toNat = x.toNat % 2 ^ System.Platform.numBits := rfl)
-    if nbits < 64 then
-      cmds := cmds.push <| ←
-        `(@[simp] theorem toNat_toUInt64 (x : $typeName) : x.toUInt64.toNat = x.toNat := rfl)
-  cmds := cmds.push <| ← `(end $typeName)
-  return ⟨mkNullNode cmds⟩
-
-declare_uint_theorems UInt8 8
-declare_uint_theorems UInt16 16
-declare_uint_theorems UInt32 32
-declare_uint_theorems UInt64 64
-declare_uint_theorems USize System.Platform.numBits
-
-@[simp] theorem USize.toNat_ofNat32 {n : Nat} {h : n < 4294967296} : (ofNat32 n h).toNat = n := rfl
-
-@[simp] theorem USize.toNat_toUInt32 (x : USize) : x.toUInt32.toNat = x.toNat % 2 ^ 32  := rfl
-
-@[simp] theorem USize.toNat_toUInt64 (x : USize) : x.toUInt64.toNat = x.toNat := rfl
-
-theorem USize.toNat_ofNat_of_lt_32 {n : Nat} (h : n < 4294967296) : toNat (ofNat n) = n :=
-  toNat_ofNat_of_lt (Nat.lt_of_lt_of_le h le_usize_size)
+declare_uint_theorems UInt8
+declare_uint_theorems UInt16
+declare_uint_theorems UInt32
+declare_uint_theorems UInt64
+declare_uint_theorems USize
 
 theorem UInt32.toNat_lt_of_lt {n : UInt32} {m : Nat} (h : m < size) : n < ofNat m → n.toNat < m := by
   simp [lt_def, BitVec.lt_def, UInt32.toNat, toBitVec_eq_of_lt h]
@@ -221,22 +145,22 @@ theorem UInt32.toNat_le_of_le {n : UInt32} {m : Nat} (h : m < size) : n ≤ ofNa
 theorem UInt32.le_toNat_of_le {n : UInt32} {m : Nat} (h : m < size) : ofNat m ≤ n → m ≤ n.toNat := by
   simp [le_def, BitVec.le_def, UInt32.toNat, toBitVec_eq_of_lt h]
 
-@[deprecated UInt8.toNat_zero (since := "2024-06-23")] protected abbrev UInt8.zero_toNat := @UInt8.toNat_zero
-@[deprecated UInt8.toNat_div (since := "2024-06-23")] protected abbrev UInt8.div_toNat := @UInt8.toNat_div
-@[deprecated UInt8.toNat_mod (since := "2024-06-23")] protected abbrev UInt8.mod_toNat := @UInt8.toNat_mod
+@[deprecated (since := "2024-06-23")] protected abbrev UInt8.zero_toNat := @UInt8.toNat_zero
+@[deprecated (since := "2024-06-23")] protected abbrev UInt8.div_toNat := @UInt8.toNat_div
+@[deprecated (since := "2024-06-23")] protected abbrev UInt8.mod_toNat := @UInt8.toNat_mod
 
-@[deprecated UInt16.toNat_zero (since := "2024-06-23")] protected abbrev UInt16.zero_toNat := @UInt16.toNat_zero
-@[deprecated UInt16.toNat_div (since := "2024-06-23")] protected abbrev UInt16.div_toNat := @UInt16.toNat_div
-@[deprecated UInt16.toNat_mod (since := "2024-06-23")] protected abbrev UInt16.mod_toNat := @UInt16.toNat_mod
+@[deprecated (since := "2024-06-23")] protected abbrev UInt16.zero_toNat := @UInt16.toNat_zero
+@[deprecated (since := "2024-06-23")] protected abbrev UInt16.div_toNat := @UInt16.toNat_div
+@[deprecated (since := "2024-06-23")] protected abbrev UInt16.mod_toNat := @UInt16.toNat_mod
 
-@[deprecated UInt32.toNat_zero (since := "2024-06-23")] protected abbrev UInt32.zero_toNat := @UInt32.toNat_zero
-@[deprecated UInt32.toNat_div (since := "2024-06-23")] protected abbrev UInt32.div_toNat := @UInt32.toNat_div
-@[deprecated UInt32.toNat_mod (since := "2024-06-23")] protected abbrev UInt32.mod_toNat := @UInt32.toNat_mod
+@[deprecated (since := "2024-06-23")] protected abbrev UInt32.zero_toNat := @UInt32.toNat_zero
+@[deprecated (since := "2024-06-23")] protected abbrev UInt32.div_toNat := @UInt32.toNat_div
+@[deprecated (since := "2024-06-23")] protected abbrev UInt32.mod_toNat := @UInt32.toNat_mod
 
-@[deprecated UInt64.toNat_zero (since := "2024-06-23")] protected abbrev UInt64.zero_toNat := @UInt64.toNat_zero
-@[deprecated UInt64.toNat_div (since := "2024-06-23")] protected abbrev UInt64.div_toNat := @UInt64.toNat_div
-@[deprecated UInt64.toNat_mod (since := "2024-06-23")] protected abbrev UInt64.mod_toNat := @UInt64.toNat_mod
+@[deprecated (since := "2024-06-23")] protected abbrev UInt64.zero_toNat := @UInt64.toNat_zero
+@[deprecated (since := "2024-06-23")] protected abbrev UInt64.div_toNat := @UInt64.toNat_div
+@[deprecated (since := "2024-06-23")] protected abbrev UInt64.mod_toNat := @UInt64.toNat_mod
 
-@[deprecated USize.toNat_zero (since := "2024-06-23")] protected abbrev USize.zero_toNat := @USize.toNat_zero
-@[deprecated USize.toNat_div (since := "2024-06-23")] protected abbrev USize.div_toNat := @USize.toNat_div
-@[deprecated USize.toNat_mod (since := "2024-06-23")] protected abbrev USize.mod_toNat := @USize.toNat_mod
+@[deprecated (since := "2024-06-23")] protected abbrev USize.zero_toNat := @USize.toNat_zero
+@[deprecated (since := "2024-06-23")] protected abbrev USize.div_toNat := @USize.toNat_div
+@[deprecated (since := "2024-06-23")] protected abbrev USize.mod_toNat := @USize.toNat_mod

src/Init/Data/Vector.lean

@@ -1,7 +0,0 @@
-/-
-Copyright (c) 2024 Lean FRO. All rights reserved.
-Released under Apache 2.0 license as described in the file LICENSE.
-Authors: Kim Morrison
--/
-prelude
-import Init.Data.Vector.Basic

src/Init/Data/Vector/Basic.lean

@@ -1,256 +0,0 @@
-/-
-Copyright (c) 2024 Shreyas Srinivas. All rights reserved.
-Released under Apache 2.0 license as described in the file LICENSE.
-Authors: Shreyas Srinivas, François G. Dorais, Kim Morrison
--/
-
-prelude
-import Init.Data.Array.Lemmas
-
-/-!
-# Vectors
-
-`Vector α n` is a thin wrapper around `Array α` for arrays of fixed size `n`.
--/
-
-/-- `Vector α n` is an `Array α` with size `n`. -/
-structure Vector (α : Type u) (n : Nat) extends Array α where
-  /-- Array size. -/
-  size_toArray : toArray.size = n
-deriving Repr, DecidableEq
-
-attribute [simp] Vector.size_toArray
-
-/-- Convert `xs : Array α` to `Vector α xs.size`. -/
-abbrev Array.toVector (xs : Array α) : Vector α xs.size := .mk xs rfl
-
-namespace Vector
-
-/-- Syntax for `Vector α n` -/
-syntax "#v[" withoutPosition(sepBy(term, ", ")) "]" : term
-
-open Lean in
-macro_rules
-  | `(#v[ $elems,* ]) => `(Vector.mk (n := $(quote elems.getElems.size)) #[$elems,*] rfl)
-
-/-- Custom eliminator for `Vector α n` through `Array α` -/
-@[elab_as_elim]
-def elimAsArray {motive : Vector α n → Sort u}
-    (mk : ∀ (a : Array α) (ha : a.size = n), motive ⟨a, ha⟩) :
-    (v : Vector α n) → motive v
-  | ⟨a, ha⟩ => mk a ha
-
-/-- Custom eliminator for `Vector α n` through `List α` -/
-@[elab_as_elim]
-def elimAsList {motive : Vector α n → Sort u}
-    (mk : ∀ (a : List α) (ha : a.length = n), motive ⟨⟨a⟩, ha⟩) :
-    (v : Vector α n) → motive v
-  | ⟨⟨a⟩, ha⟩ => mk a ha
-
-/-- Make an empty vector with pre-allocated capacity. -/
-@[inline] def mkEmpty (capacity : Nat) : Vector α 0 := ⟨.mkEmpty capacity, rfl⟩
-
-/-- Makes a vector of size `n` with all cells containing `v`. -/
-@[inline] def mkVector (n) (v : α) : Vector α n := ⟨mkArray n v, by simp⟩
-
-/-- Returns a vector of size `1` with element `v`. -/
-@[inline] def singleton (v : α) : Vector α 1 := ⟨#[v], rfl⟩
-
-instance [Inhabited α] : Inhabited (Vector α n) where
-  default := mkVector n default
-
-/-- Get an element of a vector using a `Fin` index. -/
-@[inline] def get (v : Vector α n) (i : Fin n) : α :=
-  v.toArray[(i.cast v.size_toArray.symm).1]
-
-/-- Get an element of a vector using a `USize` index and a proof that the index is within bounds. -/
-@[inline] def uget (v : Vector α n) (i : USize) (h : i.toNat < n) : α :=
-  v.toArray.uget i (v.size_toArray.symm ▸ h)
-
-instance : GetElem (Vector α n) Nat α fun _ i => i < n where
-  getElem x i h := get x ⟨i, h⟩
-
-/--
-Get an element of a vector using a `Nat` index. Returns the given default value if the index is out
-of bounds.
--/
-@[inline] def getD (v : Vector α n) (i : Nat) (default : α) : α := v.toArray.getD i default
-
-/-- The last element of a vector. Panics if the vector is empty. -/
-@[inline] def back! [Inhabited α] (v : Vector α n) : α := v.toArray.back!
-
-/-- The last element of a vector, or `none` if the array is empty. -/
-@[inline] def back? (v : Vector α n) : Option α := v.toArray.back?
-
-/-- The last element of a non-empty vector. -/
-@[inline] def back [NeZero n] (v : Vector α n) : α :=
-  -- TODO: change to just `v[n]`
-  have : Inhabited α := ⟨v[0]'(Nat.pos_of_neZero n)⟩
-  v.back!
-
-/-- The first element of a non-empty vector.  -/
-@[inline] def head [NeZero n] (v : Vector α n) := v[0]'(Nat.pos_of_neZero n)
-
-/-- Push an element `x` to the end of a vector. -/
-@[inline] def push (x : α) (v : Vector α n)  : Vector α (n + 1) :=
-  ⟨v.toArray.push x, by simp⟩
-
-/-- Remove the last element of a vector. -/
-@[inline] def pop (v : Vector α n) : Vector α (n - 1) :=
-  ⟨Array.pop v.toArray, by simp⟩
-
-/--
-Set an element in a vector using a `Nat` index, with a tactic provided proof that the index is in
-bounds.
-
-This will perform the update destructively provided that the vector has a reference count of 1.
--/
-@[inline] def set (v : Vector α n) (i : Nat) (x : α) (h : i < n := by get_elem_tactic): Vector α n :=
-  ⟨v.toArray.set i x (by simp [*]), by simp⟩
-
-/--
-Set an element in a vector using a `Nat` index. Returns the vector unchanged if the index is out of
-bounds.
-
-This will perform the update destructively provided that the vector has a reference count of 1.
--/
-@[inline] def setIfInBounds (v : Vector α n) (i : Nat) (x : α) : Vector α n :=
-  ⟨v.toArray.setIfInBounds i x, by simp⟩
-
-/--
-Set an element in a vector using a `Nat` index. Panics if the index is out of bounds.
-
-This will perform the update destructively provided that the vector has a reference count of 1.
--/
-@[inline] def set! (v : Vector α n) (i : Nat) (x : α) : Vector α n :=
-  ⟨v.toArray.set! i x, by simp⟩
-
-/-- Append two vectors. -/
-@[inline] def append (v : Vector α n) (w : Vector α m) : Vector α (n + m) :=
-  ⟨v.toArray ++ w.toArray, by simp⟩
-
-instance : HAppend (Vector α n) (Vector α m) (Vector α (n + m)) where
-  hAppend := append
-
-/-- Creates a vector from another with a provably equal length. -/
-@[inline] protected def cast (h : n = m) (v : Vector α n) : Vector α m :=
-  ⟨v.toArray, by simp [*]⟩
-
-/--
-Extracts the slice of a vector from indices `start` to `stop` (exclusive). If `start ≥ stop`, the
-result is empty. If `stop` is greater than the size of the vector, the size is used instead.
--/
-@[inline] def extract (v : Vector α n) (start stop : Nat) : Vector α (min stop n - start) :=
-  ⟨v.toArray.extract start stop, by simp⟩
-
-/-- Maps elements of a vector using the function `f`. -/
-@[inline] def map (f : α → β) (v : Vector α n) : Vector β n :=
-  ⟨v.toArray.map f, by simp⟩
-
-/-- Maps corresponding elements of two vectors of equal size using the function `f`. -/
-@[inline] def zipWith (a : Vector α n) (b : Vector β n) (f : α → β → φ) : Vector φ n :=
-  ⟨Array.zipWith a.toArray b.toArray f, by simp⟩
-
-/-- The vector of length `n` whose `i`-th element is `f i`. -/
-@[inline] def ofFn (f : Fin n → α) : Vector α n :=
-  ⟨Array.ofFn f, by simp⟩
-
-/--
-Swap two elements of a vector using `Fin` indices.
-
-This will perform the update destructively provided that the vector has a reference count of 1.
--/
-@[inline] def swap (v : Vector α n) (i j : Nat)
-    (hi : i < n := by get_elem_tactic) (hj : j < n := by get_elem_tactic) : Vector α n :=
-  ⟨v.toArray.swap i j (by simpa using hi) (by simpa using hj), by simp⟩
-
-/--
-Swap two elements of a vector using `Nat` indices. Panics if either index is out of bounds.
-
-This will perform the update destructively provided that the vector has a reference count of 1.
--/
-@[inline] def swapIfInBounds (v : Vector α n) (i j : Nat) : Vector α n :=
-  ⟨v.toArray.swapIfInBounds i j, by simp⟩
-
-/--
-Swaps an element of a vector with a given value using a `Fin` index. The original value is returned
-along with the updated vector.
-
-This will perform the update destructively provided that the vector has a reference count of 1.
--/
-@[inline] def swapAt (v : Vector α n) (i : Nat) (x : α) (hi : i < n := by get_elem_tactic) :
-    α × Vector α n :=
-  let a := v.toArray.swapAt i x (by simpa using hi)
-  ⟨a.fst, a.snd, by simp [a]⟩
-
-/--
-Swaps an element of a vector with a given value using a `Nat` index. Panics if the index is out of
-bounds. The original value is returned along with the updated vector.
-
-This will perform the update destructively provided that the vector has a reference count of 1.
--/
-@[inline] def swapAt! (v : Vector α n) (i : Nat) (x : α) : α × Vector α n :=
-  let a := v.toArray.swapAt! i x
-  ⟨a.fst, a.snd, by simp [a]⟩
-
-/-- The vector `#v[0,1,2,...,n-1]`. -/
-@[inline] def range (n : Nat) : Vector Nat n := ⟨Array.range n, by simp⟩
-
-/--
-Extract the first `m` elements of a vector. If `m` is greater than or equal to the size of the
-vector then the vector is returned unchanged.
--/
-@[inline] def take (v : Vector α n) (m : Nat) : Vector α (min m n) :=
-  ⟨v.toArray.take m, by simp⟩
-
-/--
-Deletes the first `m` elements of a vector. If `m` is greater than or equal to the size of the
-vector then the empty vector is returned.
--/
-@[inline] def drop (v : Vector α n) (m : Nat) : Vector α (n - m) :=
-  ⟨v.toArray.extract m v.size, by simp⟩
-
-/--
-Compares two vectors of the same size using a given boolean relation `r`. `isEqv v w r` returns
-`true` if and only if `r v[i] w[i]` is true for all indices `i`.
--/
-@[inline] def isEqv (v w : Vector α n) (r : α → α → Bool) : Bool :=
-  Array.isEqvAux v.toArray w.toArray (by simp) r n (by simp)
-
-instance [BEq α] : BEq (Vector α n) where
-  beq a b := isEqv a b (· == ·)
-
-/-- Reverse the elements of a vector. -/
-@[inline] def reverse (v : Vector α n) : Vector α n :=
-  ⟨v.toArray.reverse, by simp⟩
-
-/-- Delete an element of a vector using a `Nat` index and a tactic provided proof. -/
-@[inline] def eraseIdx (v : Vector α n) (i : Nat) (h : i < n := by get_elem_tactic) :
-    Vector α (n-1) :=
-  ⟨v.toArray.eraseIdx i (v.size_toArray.symm ▸ h), by simp [Array.size_eraseIdx]⟩
-
-/-- Delete an element of a vector using a `Nat` index. Panics if the index is out of bounds. -/
-@[inline] def eraseIdx! (v : Vector α n) (i : Nat) : Vector α (n-1) :=
-  if _ : i < n then
-    v.eraseIdx i
-  else
-    have : Inhabited (Vector α (n-1)) := ⟨v.pop⟩
-    panic! "index out of bounds"
-
-/-- Delete the first element of a vector. Returns the empty vector if the input vector is empty. -/
-@[inline] def tail (v : Vector α n) : Vector α (n-1) :=
-  if _ : 0 < n then
-    v.eraseIdx 0
-  else
-    v.cast (by omega)
-
-/--
-Finds the first index of a given value in a vector using `==` for comparison. Returns `none` if the
-no element of the index matches the given value.
--/
-@[inline] def indexOf? [BEq α] (v : Vector α n) (x : α) : Option (Fin n) :=
-  (v.toArray.indexOf? x).map (Fin.cast v.size_toArray)
-
-/-- Returns `true` when `v` is a prefix of the vector `w`. -/
-@[inline] def isPrefixOf [BEq α] (v : Vector α m) (w : Vector α n) : Bool :=
-  v.toArray.isPrefixOf w.toArray

src/Init/Data/Vector/Lemmas.lean

@@ -1,426 +0,0 @@
-/-
-Copyright (c) 2024 Shreyas Srinivas. All rights reserved.
-Released under Apache 2.0 license as described in the file LICENSE.
-Authors: Shreyas Srinivas, Francois Dorais
--/
-prelude
-import Init.Data.Vector.Basic
-
-/-!
-## Vectors
-Lemmas about `Vector α n`
--/
-
-namespace Array
-
-theorem toVector_inj {a b : Array α} (h₁ : a.size = b.size) (h₂ : a.toVector.cast h₁ = b.toVector) : a = b := by
-  ext i ih₁ ih₂
-  · exact h₁
-  · simpa using congrArg (fun a => a[i]) h₂
-
-end Array
-
-namespace Vector
-
-@[simp] theorem getElem_mk {data : Array α} {size : data.size = n} {i : Nat} (h : i < n) :
-    (Vector.mk data size)[i] = data[i] := rfl
-
-@[simp] theorem getElem_toArray {α n} (xs : Vector α n) (i : Nat) (h : i < xs.toArray.size) :
-    xs.toArray[i] = xs[i]'(by simpa using h) := by
-  cases xs
-  simp
-
-@[simp] theorem getElem_ofFn {α n} (f : Fin n → α) (i : Nat) (h : i < n) :
-    (Vector.ofFn f)[i] = f ⟨i, by simpa using h⟩ := by
-  simp [ofFn]
-
-/-- The empty vector maps to the empty vector. -/
-@[simp]
-theorem map_empty (f : α → β) : map f #v[] = #v[] := by
-  rw [map, mk.injEq]
-  exact Array.map_empty f
-
-theorem toArray_inj : ∀ {v w : Vector α n}, v.toArray = w.toArray → v = w
-  | {..}, {..}, rfl => rfl
-
-/-- A vector of length `0` is the empty vector. -/
-protected theorem eq_empty (v : Vector α 0) : v = #v[] := by
-  apply Vector.toArray_inj
-  apply Array.eq_empty_of_size_eq_zero v.2
-
-/--
-`Vector.ext` is an extensionality theorem.
-Vectors `a` and `b` are equal to each other if their elements are equal for each valid index.
--/
-@[ext]
-protected theorem ext {a b : Vector α n} (h : (i : Nat) → (_ : i < n) → a[i] = b[i]) : a = b := by
-  apply Vector.toArray_inj
-  apply Array.ext
-  · rw [a.size_toArray, b.size_toArray]
-  · intro i hi _
-    rw [a.size_toArray] at hi
-    exact h i hi
-
-@[simp] theorem push_mk {data : Array α} {size : data.size = n} {x : α} :
-    (Vector.mk data size).push x =
-      Vector.mk (data.push x) (by simp [size, Nat.succ_eq_add_one]) := rfl
-
-@[simp] theorem pop_mk {data : Array α} {size : data.size = n} :
-    (Vector.mk data size).pop = Vector.mk data.pop (by simp [size]) := rfl
-
-@[simp] theorem getElem_push_last {v : Vector α n} {x : α} : (v.push x)[n] = x := by
-  rcases v with ⟨data, rfl⟩
-  simp
-
-@[simp] theorem getElem_push_lt {v : Vector α n} {x : α} {i : Nat} (h : i < n) :
-    (v.push x)[i] = v[i] := by
-  rcases v with ⟨data, rfl⟩
-  simp [Array.getElem_push_lt, h]
-
-@[simp] theorem getElem_pop {v : Vector α n} {i : Nat} (h : i < n - 1) : (v.pop)[i] = v[i] := by
-  rcases v with ⟨data, rfl⟩
-  simp
-
-/--
-Variant of `getElem_pop` that will sometimes fire when `getElem_pop` gets stuck because of
-defeq issues in the implicit size argument.
--/
-@[simp] theorem getElem_pop' (v : Vector α (n + 1)) (i : Nat) (h : i < n + 1 - 1) :
-    @getElem (Vector α n) Nat α (fun _ i => i < n) instGetElemNatLt v.pop i h = v[i] :=
-  getElem_pop h
-
-@[simp] theorem push_pop_back (v : Vector α (n + 1)) : v.pop.push v.back = v := by
-  ext i
-  by_cases h : i < n
-  · simp [h]
-  · replace h : i = v.size - 1 := by rw [size_toArray]; omega
-    subst h
-    simp [pop, back, back!, ← Array.eq_push_pop_back!_of_size_ne_zero]
-
-
-/-! ### mk lemmas -/
-
-theorem toArray_mk (a : Array α) (h : a.size = n) : (Vector.mk a h).toArray = a := rfl
-
-@[simp] theorem allDiff_mk [BEq α] (a : Array α) (h : a.size = n) :
-    (Vector.mk a h).allDiff = a.allDiff := rfl
-
-@[simp] theorem mk_append_mk (a b : Array α) (ha : a.size = n) (hb : b.size = m) :
-    Vector.mk a ha ++ Vector.mk b hb = Vector.mk (a ++ b) (by simp [ha, hb]) := rfl
-
-@[simp] theorem back!_mk [Inhabited α] (a : Array α) (h : a.size = n) :
-    (Vector.mk a h).back! = a.back! := rfl
-
-@[simp] theorem back?_mk (a : Array α) (h : a.size = n) :
-    (Vector.mk a h).back? = a.back? := rfl
-
-@[simp] theorem drop_mk (a : Array α) (h : a.size = n) (m) :
-    (Vector.mk a h).drop m = Vector.mk (a.extract m a.size) (by simp [h]) := rfl
-
-@[simp] theorem eraseIdx_mk (a : Array α) (h : a.size = n) (i) (h') :
-    (Vector.mk a h).eraseIdx i h' = Vector.mk (a.eraseIdx i) (by simp [h]) := rfl
-
-@[simp] theorem eraseIdx!_mk (a : Array α) (h : a.size = n) (i) (hi : i < n) :
-    (Vector.mk a h).eraseIdx! i = Vector.mk (a.eraseIdx i) (by simp [h, hi]) := by
-  simp [Vector.eraseIdx!, hi]
-
-@[simp] theorem cast_mk (a : Array α) (h : a.size = n) (h' : n = m) :
-    (Vector.mk a h).cast h' = Vector.mk a (by simp [h, h']) := rfl
-
-@[simp] theorem extract_mk (a : Array α) (h : a.size = n) (start stop) :
-    (Vector.mk a h).extract start stop = Vector.mk (a.extract start stop) (by simp [h]) := rfl
-
-@[simp] theorem indexOf?_mk [BEq α] (a : Array α) (h : a.size = n) (x : α) :
-    (Vector.mk a h).indexOf? x = (a.indexOf? x).map (Fin.cast h) := rfl
-
-@[simp] theorem mk_isEqv_mk (r : α → α → Bool) (a b : Array α) (ha : a.size = n) (hb : b.size = n) :
-    Vector.isEqv (Vector.mk a ha) (Vector.mk b hb) r = Array.isEqv a b r := by
-  simp [Vector.isEqv, Array.isEqv, ha, hb]
-
-@[simp] theorem mk_isPrefixOf_mk [BEq α] (a b : Array α) (ha : a.size = n) (hb : b.size = m) :
-    (Vector.mk a ha).isPrefixOf (Vector.mk b hb) = a.isPrefixOf b := rfl
-
-@[simp] theorem map_mk (a : Array α) (h : a.size = n) (f : α → β) :
-    (Vector.mk a h).map f = Vector.mk (a.map f) (by simp [h]) := rfl
-
-@[simp] theorem reverse_mk (a : Array α) (h : a.size = n) :
-    (Vector.mk a h).reverse = Vector.mk a.reverse (by simp [h]) := rfl
-
-@[simp] theorem set_mk (a : Array α) (h : a.size = n) (i x w) :
-    (Vector.mk a h).set i x = Vector.mk (a.set i x) (by simp [h]) := rfl
-
-@[simp] theorem set!_mk (a : Array α) (h : a.size = n) (i x) :
-    (Vector.mk a h).set! i x = Vector.mk (a.set! i x) (by simp [h]) := rfl
-
-@[simp] theorem setIfInBounds_mk (a : Array α) (h : a.size = n) (i x) :
-    (Vector.mk a h).setIfInBounds i x = Vector.mk (a.setIfInBounds i x) (by simp [h]) := rfl
-
-@[simp] theorem swap_mk (a : Array α) (h : a.size = n) (i j) (hi hj) :
-    (Vector.mk a h).swap i j = Vector.mk (a.swap i j) (by simp [h]) :=
-  rfl
-
-@[simp] theorem swapIfInBounds_mk (a : Array α) (h : a.size = n) (i j) :
-    (Vector.mk a h).swapIfInBounds i j = Vector.mk (a.swapIfInBounds i j) (by simp [h]) := rfl
-
-@[simp] theorem swapAt_mk (a : Array α) (h : a.size = n) (i x) (hi) :
-    (Vector.mk a h).swapAt i x =
-      ((a.swapAt i x).fst, Vector.mk (a.swapAt i x).snd (by simp [h])) :=
-  rfl
-
-@[simp] theorem swapAt!_mk (a : Array α) (h : a.size = n) (i x) : (Vector.mk a h).swapAt! i x =
-    ((a.swapAt! i x).fst, Vector.mk (a.swapAt! i x).snd (by simp [h])) := rfl
-
-@[simp] theorem take_mk (a : Array α) (h : a.size = n) (m) :
-    (Vector.mk a h).take m = Vector.mk (a.take m) (by simp [h]) := rfl
-
-@[simp] theorem mk_zipWith_mk (f : α → β → γ) (a : Array α) (b : Array β)
-      (ha : a.size = n) (hb : b.size = n) : zipWith (Vector.mk a ha) (Vector.mk b hb) f =
-        Vector.mk (Array.zipWith a b f) (by simp [ha, hb]) := rfl
-
-/-! ### toArray lemmas -/
-
-@[simp] theorem toArray_append (a : Vector α m) (b : Vector α n) :
-    (a ++ b).toArray = a.toArray ++ b.toArray := rfl
-
-@[simp] theorem toArray_drop (a : Vector α n) (m) :
-    (a.drop m).toArray = a.toArray.extract m a.size := rfl
-
-@[simp] theorem toArray_empty : (#v[] : Vector α 0).toArray = #[] := rfl
-
-@[simp] theorem toArray_mkEmpty (cap) :
-    (Vector.mkEmpty (α := α) cap).toArray = Array.mkEmpty cap := rfl
-
-@[simp] theorem toArray_eraseIdx (a : Vector α n) (i) (h) :
-    (a.eraseIdx i h).toArray = a.toArray.eraseIdx i (by simp [h]) := rfl
-
-@[simp] theorem toArray_eraseIdx! (a : Vector α n) (i) (hi : i < n) :
-    (a.eraseIdx! i).toArray = a.toArray.eraseIdx! i := by
-  cases a; simp_all [Array.eraseIdx!]
-
-@[simp] theorem toArray_cast (a : Vector α n) (h : n = m) :
-    (a.cast h).toArray = a.toArray := rfl
-
-@[simp] theorem toArray_extract (a : Vector α n) (start stop) :
-    (a.extract start stop).toArray = a.toArray.extract start stop := rfl
-
-@[simp] theorem toArray_map (f : α → β) (a : Vector α n) :
-    (a.map f).toArray = a.toArray.map f := rfl
-
-@[simp] theorem toArray_ofFn (f : Fin n → α) : (Vector.ofFn f).toArray = Array.ofFn f := rfl
-
-@[simp] theorem toArray_pop (a : Vector α n) : a.pop.toArray = a.toArray.pop := rfl
-
-@[simp] theorem toArray_push (a : Vector α n) (x) : (a.push x).toArray = a.toArray.push x := rfl
-
-@[simp] theorem toArray_range : (Vector.range n).toArray = Array.range n := rfl
-
-@[simp] theorem toArray_reverse (a : Vector α n) : a.reverse.toArray = a.toArray.reverse := rfl
-
-@[simp] theorem toArray_set (a : Vector α n) (i x h) :
-    (a.set i x).toArray = a.toArray.set i x (by simpa using h):= rfl
-
-@[simp] theorem toArray_set! (a : Vector α n) (i x) :
-    (a.set! i x).toArray = a.toArray.set! i x := rfl
-
-@[simp] theorem toArray_setIfInBounds (a : Vector α n) (i x) :
-    (a.setIfInBounds i x).toArray = a.toArray.setIfInBounds i x := rfl
-
-@[simp] theorem toArray_singleton (x : α) : (Vector.singleton x).toArray = #[x] := rfl
-
-@[simp] theorem toArray_swap (a : Vector α n) (i j) (hi hj) : (a.swap i j).toArray =
-    a.toArray.swap i j (by simp [hi, hj]) (by simp [hi, hj]) := rfl
-
-@[simp] theorem toArray_swapIfInBounds (a : Vector α n) (i j) :
-    (a.swapIfInBounds i j).toArray = a.toArray.swapIfInBounds i j := rfl
-
-@[simp] theorem toArray_swapAt (a : Vector α n) (i x h) :
-    ((a.swapAt i x).fst, (a.swapAt i x).snd.toArray) =
-      ((a.toArray.swapAt i x (by simpa using h)).fst,
-        (a.toArray.swapAt i x (by simpa using h)).snd) := rfl
-
-@[simp] theorem toArray_swapAt! (a : Vector α n) (i x) :
-    ((a.swapAt! i x).fst, (a.swapAt! i x).snd.toArray) =
-      ((a.toArray.swapAt! i x).fst, (a.toArray.swapAt! i x).snd) := rfl
-
-@[simp] theorem toArray_take (a : Vector α n) (m) : (a.take m).toArray = a.toArray.take m := rfl
-
-@[simp] theorem toArray_zipWith (f : α → β → γ) (a : Vector α n) (b : Vector β n) :
-    (Vector.zipWith a b f).toArray = Array.zipWith a.toArray b.toArray f := rfl
-
-/-! ### toList lemmas -/
-
-theorem length_toList {α n} (xs : Vector α n) : xs.toList.length = n := by simp
-
-theorem getElem_toList {α n} (xs : Vector α n) (i : Nat) (h : i < xs.toList.length) :
-    xs.toList[i] = xs[i]'(by simpa using h) := by simp
-
-theorem toList_inj {a b : Vector α n} (h : a.toList = b.toList) : a = b := by
-  rcases a with ⟨⟨a⟩, ha⟩
-  rcases b with ⟨⟨b⟩, hb⟩
-  simpa using h
-
-/-! ### set -/
-
-theorem getElem_set (a : Vector α n) (i : Nat) (x : α) (hi : i < n) (j : Nat) (hj : j < n) :
-    (a.set i x hi)[j] = if i = j then x else a[j] := by
-  cases a
-  split <;> simp_all [Array.getElem_set]
-
-@[simp] theorem getElem_set_eq (a : Vector α n) (i : Nat) (x : α) (hi : i < n) :
-    (a.set i x hi)[i] = x := by simp [getElem_set]
-
-@[simp] theorem getElem_set_ne (a : Vector α n) (i : Nat) (x : α) (hi : i < n) (j : Nat)
-    (hj : j < n) (h : i ≠ j) : (a.set i x hi)[j] = a[j] := by simp [getElem_set, h]
-
-/-! ### setIfInBounds -/
-
-theorem getElem_setIfInBounds (a : Vector α n) (i : Nat) (x : α) (j : Nat)
-    (hj : j < n) : (a.setIfInBounds i x)[j] = if i = j then x else a[j] := by
-  cases a
-  split <;> simp_all [Array.getElem_setIfInBounds]
-
-@[simp] theorem getElem_setIfInBounds_eq (a : Vector α n) (i : Nat) (x : α) (hj : i < n) :
-    (a.setIfInBounds i x)[i] = x := by simp [getElem_setIfInBounds]
-
-@[simp] theorem getElem_setIfInBounds_ne (a : Vector α n) (i : Nat) (x : α) (j : Nat)
-    (hj : j < n) (h : i ≠ j) : (a.setIfInBounds i x)[j] = a[j] := by simp [getElem_setIfInBounds, h]
-
-/-! ### append -/
-
-theorem getElem_append (a : Vector α n) (b : Vector α m) (i : Nat) (hi : i < n + m) :
-    (a ++ b)[i] = if h : i < n then a[i] else b[i - n] := by
-  rcases a with ⟨a, rfl⟩
-  rcases b with ⟨b, rfl⟩
-  simp [Array.getElem_append, hi]
-
-theorem getElem_append_left {a : Vector α n} {b : Vector α m} {i : Nat} (hi : i < n) :
-    (a ++ b)[i] = a[i] := by simp [getElem_append, hi]
-
-theorem getElem_append_right {a : Vector α n} {b : Vector α m} {i : Nat} (h : i < n + m) (hi : n ≤ i) :
-    (a ++ b)[i] = b[i - n] := by
-  rw [getElem_append, dif_neg (by omega)]
-
-/-! ### cast -/
-
-@[simp] theorem getElem_cast (a : Vector α n) (h : n = m) (i : Nat) (hi : i < m) :
-    (a.cast h)[i] = a[i] := by
-  cases a
-  simp
-
-/-! ### extract -/
-
-@[simp] theorem getElem_extract (a : Vector α n) (start stop) (i : Nat) (hi : i < min stop n - start) :
-    (a.extract start stop)[i] = a[start + i] := by
-  cases a
-  simp
-
-/-! ### map -/
-
-@[simp] theorem getElem_map (f : α → β) (a : Vector α n) (i : Nat) (hi : i < n) :
-    (a.map f)[i] = f a[i] := by
-  cases a
-  simp
-
-/-! ### zipWith -/
-
-@[simp] theorem getElem_zipWith (f : α → β → γ) (a : Vector α n) (b : Vector β n) (i : Nat)
-    (hi : i < n) : (zipWith a b f)[i] = f a[i] b[i] := by
-  cases a
-  cases b
-  simp
-
-/-! ### swap -/
-
-theorem getElem_swap (a : Vector α n) (i j : Nat) {hi hj} (k : Nat) (hk : k < n) :
-    (a.swap i j hi hj)[k] = if k = i then a[j] else if k = j then a[i] else a[k] := by
-  cases a
-  simp_all [Array.getElem_swap]
-
-@[simp] theorem getElem_swap_right (a : Vector α n) {i j : Nat} {hi hj} :
-    (a.swap i j hi hj)[j]'(by simpa using hj) = a[i] := by
-  simp +contextual [getElem_swap]
-
-@[simp] theorem getElem_swap_left (a : Vector α n) {i j : Nat} {hi hj} :
-    (a.swap i j hi hj)[i]'(by simpa using hi) = a[j] := by
-  simp [getElem_swap]
-
-@[simp] theorem getElem_swap_of_ne (a : Vector α n) {i j : Nat} {hi hj} (hp : p < n)
-    (hi' : p ≠ i) (hj' : p ≠ j) : (a.swap i j hi hj)[p] = a[p] := by
-  simp_all [getElem_swap]
-
-@[simp] theorem swap_swap (a : Vector α n) {i j : Nat} {hi hj} :
-    (a.swap i j hi hj).swap i j hi hj = a := by
-  cases a
-  simp_all [Array.swap_swap]
-
-theorem swap_comm (a : Vector α n) {i j : Nat} {hi hj} :
-    a.swap i j hi hj = a.swap j i hj hi := by
-  cases a
-  simp only [swap_mk, mk.injEq]
-  rw [Array.swap_comm]
-
-/-! ### range -/
-
-@[simp] theorem getElem_range (i : Nat) (hi : i < n) : (Vector.range n)[i] = i := by
-  simp [Vector.range]
-
-/-! ### take -/
-
-@[simp] theorem getElem_take (a : Vector α n) (m : Nat) (hi : i < min n m) :
-    (a.take m)[i] = a[i] := by
-  cases a
-  simp
-
-/-! ### drop -/
-
-@[simp] theorem getElem_drop (a : Vector α n) (m : Nat) (hi : i < n - m) :
-    (a.drop m)[i] = a[m + i] := by
-  cases a
-  simp
-
-/-! ### reverse -/
-
-@[simp] theorem getElem_reverse (a : Vector α n) (i : Nat) (hi : i < n) :
-    (a.reverse)[i] = a[n - 1 - i] := by
-  rcases a with ⟨a, rfl⟩
-  simp
-
-/-! ### Decidable quantifiers. -/
-
-theorem forall_zero_iff {P : Vector α 0 → Prop} :
-    (∀ v, P v) ↔ P #v[] := by
-  constructor
-  · intro h
-    apply h
-  · intro h v
-    obtain (rfl : v = #v[]) := (by ext i h; simp at h)
-    apply h
-
-theorem forall_cons_iff {P : Vector α (n + 1) → Prop} :
-    (∀ v : Vector α (n + 1), P v) ↔ (∀ (x : α) (v : Vector α n), P (v.push x)) := by
-  constructor
-  · intro h _ _
-    apply h
-  · intro h v
-    have w : v = v.pop.push v.back := by simp
-    rw [w]
-    apply h
-
-instance instDecidableForallVectorZero (P : Vector α 0 → Prop) :
-    ∀ [Decidable (P #v[])], Decidable (∀ v, P v)
-  | .isTrue h => .isTrue fun ⟨v, s⟩ => by
-    obtain (rfl : v = .empty) := (by ext i h₁ h₂; exact s; cases h₂)
-    exact h
-  | .isFalse h => .isFalse (fun w => h (w _))
-
-instance instDecidableForallVectorSucc (P : Vector α (n+1) → Prop)
-    [Decidable (∀ (x : α) (v : Vector α n), P (v.push x))] : Decidable (∀ v, P v) :=
-  decidable_of_iff' (∀ x (v : Vector α n), P (v.push x)) forall_cons_iff
-
-instance instDecidableExistsVectorZero (P : Vector α 0 → Prop) [Decidable (P #v[])] :
-    Decidable (∃ v, P v) :=
-  decidable_of_iff (¬ ∀ v, ¬ P v) Classical.not_forall_not
-
-instance instDecidableExistsVectorSucc (P : Vector α (n+1) → Prop)
-    [Decidable (∀ (x : α) (v : Vector α n), ¬ P (v.push x))] : Decidable (∃ v, P v) :=
-  decidable_of_iff (¬ ∀ v, ¬ P v) Classical.not_forall_not

src/Init/GetElem.lean

@@ -118,16 +118,12 @@ instance (priority := low) [GetElem coll idx elem valid] [∀ xs i, Decidable (v
     GetElem? coll idx elem valid where
   getElem? xs i := decidableGetElem? xs i
 
-theorem getElem_congr [GetElem coll idx elem valid] {c d : coll} (h : c = d)
-    {i j : idx} (h' : i = j) (w : valid c i) : c[i] = d[j]'(h' ▸ h ▸ w) := by
-  cases h; cases h'; rfl
+theorem getElem_congr_coll [GetElem coll idx elem valid] {c d : coll} {i : idx} {h : valid c i}
+    (h' : c = d) : c[i] = d[i]'(h' ▸ h) := by
+  cases h'; rfl
 
-theorem getElem_congr_coll [GetElem coll idx elem valid] {c d : coll} {i : idx} {w : valid c i}
-    (h : c = d) : c[i] = d[i]'(h ▸ w) := by
-  cases h; rfl
-
-theorem getElem_congr_idx [GetElem coll idx elem valid] {c : coll} {i j : idx} {w : valid c i}
-    (h' : i = j) : c[i] = c[j]'(h' ▸ w) := by
+theorem getElem_congr [GetElem coll idx elem valid] {c : coll} {i j : idx} {h : valid c i}
+    (h' : i = j) : c[i] = c[j]'(h' ▸ h) := by
   cases h'; rfl
 
 class LawfulGetElem (cont : Type u) (idx : Type v) (elem : outParam (Type w))
@@ -176,16 +172,6 @@ theorem getElem!_neg [GetElem? cont idx elem dom] [LawfulGetElem cont idx elem d
   simp only [getElem?_def] at h ⊢
   split <;> simp_all
 
-@[simp] theorem isNone_getElem? [GetElem? cont idx elem dom] [LawfulGetElem cont idx elem dom]
-    (c : cont) (i : idx) [Decidable (dom c i)] : c[i]?.isNone = ¬dom c i := by
-  simp only [getElem?_def]
-  split <;> simp_all
-
-@[simp] theorem isSome_getElem? [GetElem? cont idx elem dom] [LawfulGetElem cont idx elem dom]
-    (c : cont) (i : idx) [Decidable (dom c i)] : c[i]?.isSome = dom c i := by
-  simp only [getElem?_def]
-  split <;> simp_all
-
 namespace Fin
 
 instance instGetElemFinVal [GetElem cont Nat elem dom] : GetElem cont (Fin n) elem fun xs i => dom xs i where
@@ -220,9 +206,13 @@ instance : GetElem (List α) Nat α fun as i => i < as.length where
 @[simp] theorem getElem_cons_zero (a : α) (as : List α) (h : 0 < (a :: as).length) : getElem (a :: as) 0 h = a := by
   rfl
 
+@[deprecated (since := "2024-06-12")] abbrev cons_getElem_zero := @getElem_cons_zero
+
 @[simp] theorem getElem_cons_succ (a : α) (as : List α) (i : Nat) (h : i + 1 < (a :: as).length) : getElem (a :: as) (i+1) h = getElem as i (Nat.lt_of_succ_lt_succ h) := by
   rfl
 
+@[deprecated (since := "2024-06-12")] abbrev cons_getElem_succ := @getElem_cons_succ
+
 @[simp] theorem getElem_mem : ∀ {l : List α} {n} (h : n < l.length), l[n]'h ∈ l
   | _ :: _, 0, _ => .head ..
   | _ :: l, _+1, _ => .tail _ (getElem_mem (l := l) ..)
@@ -231,10 +221,9 @@ theorem getElem_cons_drop_succ_eq_drop {as : List α} {i : Nat} (h : i < as.leng
     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) (Nat.add_one_lt_add_one_iff.mp h)
+  | _::_, i+1 => getElem_cons_drop_succ_eq_drop (i := i) _
 
-@[deprecated getElem_cons_drop_succ_eq_drop (since := "2024-11-05")]
-abbrev get_drop_eq_drop := @getElem_cons_drop_succ_eq_drop
+@[deprecated (since := "2024-11-05")] abbrev get_drop_eq_drop := @getElem_cons_drop_succ_eq_drop
 
 end List
 
@@ -243,12 +232,6 @@ namespace Array
 instance : GetElem (Array α) Nat α fun xs i => i < xs.size where
   getElem xs i h := xs.get i h
 
-@[simp] theorem get_eq_getElem (a : Array α) (i : Nat) (h) : a.get i h = a[i] := rfl
-
-@[simp] theorem get!_eq_getElem! [Inhabited α] (a : Array α) (i : Nat) : a.get! i = a[i]! := by
-  simp only [get!, getD, get_eq_getElem, getElem!_def]
-  split <;> simp_all [getElem?_pos, getElem?_neg]
-
 end Array
 
 namespace Lean.Syntax

src/Init/Meta.lean

@@ -374,9 +374,6 @@ partial def structEq : Syntax → Syntax → Bool
 instance : BEq Lean.Syntax := ⟨structEq⟩
 instance : BEq (Lean.TSyntax k) := ⟨(·.raw == ·.raw)⟩
 
-/--
-Finds the first `SourceInfo` from the back of `stx` or `none` if no `SourceInfo` can be found.
--/
 partial def getTailInfo? : Syntax → Option SourceInfo
   | atom info _   => info
   | ident info .. => info
@@ -385,39 +382,14 @@ partial def getTailInfo? : Syntax → Option SourceInfo
   | node info _ _    => info
   | _             => none
 
-/--
-Finds the first `SourceInfo` from the back of `stx` or `SourceInfo.none`
-if no `SourceInfo` can be found.
--/
 def getTailInfo (stx : Syntax) : SourceInfo :=
   stx.getTailInfo?.getD SourceInfo.none
 
-/--
-Finds the trailing size of the first `SourceInfo` from the back of `stx`.
-If no `SourceInfo` can be found or the first `SourceInfo` from the back of `stx` contains no
-trailing whitespace, the result is `0`.
--/
 def getTrailingSize (stx : Syntax) : Nat :=
   match stx.getTailInfo? with
   | some (SourceInfo.original (trailing := trailing) ..) => trailing.bsize
   | _ => 0
 
-/--
-Finds the trailing whitespace substring of the first `SourceInfo` from the back of `stx`.
-If no `SourceInfo` can be found or the first `SourceInfo` from the back of `stx` contains
-no trailing whitespace, the result is `none`.
--/
-def getTrailing? (stx : Syntax) : Option Substring :=
-  stx.getTailInfo.getTrailing?
-
-/--
-Finds the tail position of the trailing whitespace of the first `SourceInfo` from the back of `stx`.
-If no `SourceInfo` can be found or the first `SourceInfo` from the back of `stx` contains
-no trailing whitespace and lacks a tail position, the result is `none`.
--/
-def getTrailingTailPos? (stx : Syntax) (canonicalOnly := false) : Option String.Pos :=
-  stx.getTailInfo.getTrailingTailPos? canonicalOnly
-
 /--
   Return substring of original input covering `stx`.
   Result is meaningful only if all involved `SourceInfo.original`s refer to the same string (as is the case after parsing). -/
@@ -431,20 +403,21 @@ def getSubstring? (stx : Syntax) (withLeading := true) (withTrailing := true) :
     }
   | _, _ => none
 
-@[specialize] private partial def updateLast {α} (a : Array α) (f : α → Option α) (i : Fin (a.size + 1)) : Option (Array α) :=
-  match i with
-  | 0 => none
-  | ⟨i + 1, h⟩ =>
-    let v := a[i]'(Nat.succ_lt_succ_iff.mp h)
+@[specialize] private partial def updateLast {α} [Inhabited α] (a : Array α) (f : α → Option α) (i : Nat) : Option (Array α) :=
+  if i == 0 then
+    none
+  else
+    let i := i - 1
+    let v := a[i]!
     match f v with
-    | some v => some <| a.set i v (Nat.succ_lt_succ_iff.mp h)
-    | none   => updateLast a f ⟨i, Nat.lt_of_succ_lt h⟩
+    | some v => some <| a.set! i v
+    | none   => updateLast a f i
 
 partial def setTailInfoAux (info : SourceInfo) : Syntax → Option Syntax
   | atom _ val             => some <| atom info val
   | ident _ rawVal val pre => some <| ident info rawVal val pre
   | node info' k args      =>
-    match updateLast args (setTailInfoAux info) ⟨args.size, by simp⟩ with
+    match updateLast args (setTailInfoAux info) args.size with
     | some args => some <| node info' k args
     | none      => none
   | _                      => none
@@ -679,7 +652,6 @@ private partial def decodeBinLitAux (s : String) (i : String.Pos) (val : Nat) :
     let c := s.get i
     if c == '0' then decodeBinLitAux s (s.next i) (2*val)
     else if c == '1' then decodeBinLitAux s (s.next i) (2*val + 1)
-    else if c == '_' then decodeBinLitAux s (s.next i) val
     else none
 
 private partial def decodeOctalLitAux (s : String) (i : String.Pos) (val : Nat) : Option Nat :=
@@ -687,7 +659,6 @@ private partial def decodeOctalLitAux (s : String) (i : String.Pos) (val : Nat)
   else
     let c := s.get i
     if '0' ≤ c && c ≤ '7' then decodeOctalLitAux s (s.next i) (8*val + c.toNat - '0'.toNat)
-    else if c == '_' then decodeOctalLitAux s (s.next i) val
     else none
 
 private def decodeHexDigit (s : String) (i : String.Pos) : Option (Nat × String.Pos) :=
@@ -702,16 +673,13 @@ private partial def decodeHexLitAux (s : String) (i : String.Pos) (val : Nat) :
   if s.atEnd i then some val
   else match decodeHexDigit s i with
     | some (d, i) => decodeHexLitAux s i (16*val + d)
-    | none        =>
-      if s.get i == '_' then decodeHexLitAux s (s.next i) val
-      else none
+    | none        => none
 
 private partial def decodeDecimalLitAux (s : String) (i : String.Pos) (val : Nat) : Option Nat :=
   if s.atEnd i then some val
   else
     let c := s.get i
     if '0' ≤ c && c ≤ '9' then decodeDecimalLitAux s (s.next i) (10*val + c.toNat - '0'.toNat)
-    else if c == '_' then decodeDecimalLitAux s (s.next i) val
     else none
 
 def decodeNatLitVal? (s : String) : Option Nat :=
@@ -778,8 +746,6 @@ where
       let c := s.get i
       if '0' ≤ c && c ≤ '9' then
         decodeAfterExp (s.next i) val e sign (10*exp + c.toNat - '0'.toNat)
-      else if c == '_' then
-        decodeAfterExp (s.next i) val e sign exp
       else
         none
 
@@ -800,8 +766,6 @@ where
       let c := s.get i
       if '0' ≤ c && c ≤ '9' then
         decodeAfterDot (s.next i) (10*val + c.toNat - '0'.toNat) (e+1)
-      else if c == '_' then
-        decodeAfterDot (s.next i) val e
       else if c == 'e' || c == 'E' then
         decodeExp (s.next i) val e
       else
@@ -814,8 +778,6 @@ where
       let c := s.get i
       if '0' ≤ c && c ≤ '9' then
         decode (s.next i) (10*val + c.toNat - '0'.toNat)
-      else if c == '_' then
-        decode (s.next i) val
       else if c == '.' then
         decodeAfterDot (s.next i) val 0
       else if c == 'e' || c == 'E' then

src/Init/MetaTypes.lean

@@ -224,8 +224,7 @@ structure Config where
   -/
   index             : Bool := true
   /--
-  If `implicitDefEqProofs := true`, `simp` does not create proof terms when the
-  input and output terms are definitionally equal.
+  This option does not have any effect (yet).
   -/
   implicitDefEqProofs : Bool := true
   deriving Inhabited, BEq
@@ -250,25 +249,12 @@ def neutralConfig : Simp.Config := {
   zetaDelta         := false
 }
 
-structure NormCastConfig extends Simp.Config where
-    zeta := false
-    beta := false
-    eta  := false
-    proj := false
-    iota := false
-
 end Simp
 
-/-- Configuration for which occurrences that match an expression should be rewritten. -/
 inductive Occurrences where
-  /-- All occurrences should be rewritten. -/
   | all
-  /-- A list of indices for which occurrences should be rewritten. -/
   | pos (idxs : List Nat)
-  /-- A list of indices for which occurrences should not be rewritten. -/
   | neg (idxs : List Nat)
   deriving Inhabited, BEq
 
-instance : Coe (List Nat) Occurrences := ⟨.pos⟩
-
 end Lean.Meta

src/Init/Notation.lean

@@ -48,10 +48,6 @@ def tactic : Category := {}
 For example, `let x ← e` is a `doElem`, and a `do` block consists of a list of `doElem`s. -/
 def doElem : Category := {}
 
-/-- `structInstFieldDecl` is the syntax category for value declarations for fields in structure instance notation.
-For example, the `:= 1` and `| 0 => 0 | n + 1 => n` in `{ x := 1, f | 0 => 0 | n + 1 => n }` are in the `structInstFieldDecl` class. -/
-def structInstFieldDecl : Category := {}
-
 /-- `level` is a builtin syntax category for universe levels.
 This is the `u` in `Sort u`: it can contain `max` and `imax`, addition with
 constants, and variables. -/
@@ -75,9 +71,9 @@ def prio : Category := {}
 
 /-- `prec` is a builtin syntax category for precedences. A precedence is a value
 that expresses how tightly a piece of syntax binds: for example `1 + 2 * 3` is
-parsed as `1 + (2 * 3)` because `*` has a higher precedence than `+`.
+parsed as `1 + (2 * 3)` because `*` has a higher pr0ecedence than `+`.
 Higher numbers denote higher precedence.
-In addition to literals like `37`, there are some special named precedence levels:
+In addition to literals like `37`, there are some special named priorities:
 * `arg` for the precedence of function arguments
 * `max` for the highest precedence used in term parsers (not actually the maximum possible value)
 * `lead` for the precedence of terms not supposed to be used as arguments

src/Init/NotationExtra.lean

@@ -22,28 +22,28 @@ syntax explicitBinders            := (ppSpace bracketedExplicitBinders)+ <|> unb
 
 open TSyntax.Compat in
 def expandExplicitBindersAux (combinator : Syntax) (idents : Array Syntax) (type? : Option Syntax) (body : Syntax) : MacroM Syntax :=
-  let rec loop (i : Nat) (h : i ≤ idents.size) (acc : Syntax) := do
+  let rec loop (i : Nat) (acc : Syntax) := do
     match i with
     | 0   => pure acc
-    | i + 1 =>
-      let ident := idents[i][0]
+    | i+1 =>
+      let ident := idents[i]![0]
       let acc ← match ident.isIdent, type? with
         | true,  none      => `($combinator fun $ident => $acc)
         | true,  some type => `($combinator fun $ident : $type => $acc)
         | false, none      => `($combinator fun _ => $acc)
         | false, some type => `($combinator fun _ : $type => $acc)
-      loop i (Nat.le_of_succ_le h) acc
-  loop idents.size (by simp) body
+      loop i acc
+  loop idents.size body
 
 def expandBrackedBindersAux (combinator : Syntax) (binders : Array Syntax) (body : Syntax) : MacroM Syntax :=
-  let rec loop (i : Nat) (h : i ≤ binders.size) (acc : Syntax) := do
+  let rec loop (i : Nat) (acc : Syntax) := do
     match i with
     | 0   => pure acc
     | i+1 =>
-      let idents := binders[i][1].getArgs
-      let type   := binders[i][3]
-      loop i (Nat.le_of_succ_le h) (← expandExplicitBindersAux combinator idents (some type) acc)
-  loop binders.size (by simp) body
+      let idents := binders[i]![1].getArgs
+      let type   := binders[i]![3]
+      loop i (← expandExplicitBindersAux combinator idents (some type) acc)
+  loop binders.size body
 
 def expandExplicitBinders (combinatorDeclName : Name) (explicitBinders : Syntax) (body : Syntax) : MacroM Syntax := do
   let combinator := mkCIdentFrom (← getRef) combinatorDeclName

src/Init/Omega/IntList.lean

@@ -32,9 +32,13 @@ theorem get_map {xs : IntList} (h : f 0 = 0) : get (xs.map f) i = f (xs.get i) :
   cases xs[i]? <;> simp_all
 
 theorem get_of_length_le {xs : IntList} (h : xs.length ≤ i) : xs.get i = 0 := by
-  rw [get, List.get?_eq_none_iff.mpr h]
+  rw [get, List.get?_eq_none.mpr h]
   rfl
 
+-- theorem lt_length_of_get_nonzero {xs : IntList} (h : xs.get i ≠ 0) : i < xs.length := by
+--   revert h
+--   simpa using mt get_of_length_le
+
 /-- Like `List.set`, but right-pad with zeroes as necessary first. -/
 def set (xs : IntList) (i : Nat) (y : Int) : IntList :=
   match xs, i with

src/Init/Prelude.lean

@@ -2116,11 +2116,6 @@ theorem usize_size_eq : Or (Eq USize.size 4294967296) (Eq USize.size 18446744073
   | _, Or.inl rfl => Or.inl (of_decide_eq_true rfl)
   | _, Or.inr rfl => Or.inr (of_decide_eq_true rfl)
 
-theorem usize_size_pos : LT.lt 0 USize.size :=
-  match USize.size, usize_size_eq with
-  | _, Or.inl rfl => of_decide_eq_true rfl
-  | _, Or.inr rfl => of_decide_eq_true rfl
-
 /--
 A `USize` is an unsigned integer with the size of a word
 for the platform's architecture.
@@ -2160,7 +2155,24 @@ def USize.decEq (a b : USize) : Decidable (Eq a b) :=
 instance : DecidableEq USize := USize.decEq
 
 instance : Inhabited USize where
-  default := USize.ofNatCore 0 usize_size_pos
+  default := USize.ofNatCore 0 (match USize.size, usize_size_eq with
+    | _, Or.inl rfl => of_decide_eq_true rfl
+    | _, Or.inr rfl => of_decide_eq_true rfl)
+
+/--
+Upcast a `Nat` less than `2^32` to a `USize`.
+This is lossless because `USize.size` is either `2^32` or `2^64`.
+This function is overridden with a native implementation.
+-/
+@[extern "lean_usize_of_nat"]
+def USize.ofNat32 (n : @& Nat) (h : LT.lt n 4294967296) : USize where
+  toBitVec :=
+    BitVec.ofNatLt n (
+      match System.Platform.numBits, System.Platform.numBits_eq with
+      | _, Or.inl rfl => h
+      | _, Or.inr rfl => Nat.lt_trans h (of_decide_eq_true rfl)
+    )
+
 /--
 A `Nat` denotes a valid unicode codepoint if it is less than `0x110000`, and
 it is also not a "surrogate" character (the range `0xd800` to `0xdfff` inclusive).
@@ -3420,6 +3432,25 @@ class Hashable (α : Sort u) where
 
 export Hashable (hash)
 
+/-- Converts a `UInt64` to a `USize` by reducing modulo `USize.size`. -/
+@[extern "lean_uint64_to_usize"]
+opaque UInt64.toUSize (u : UInt64) : USize
+
+/--
+Upcast a `USize` to a `UInt64`.
+This is lossless because `USize.size` is either `2^32` or `2^64`.
+This function is overridden with a native implementation.
+-/
+@[extern "lean_usize_to_uint64"]
+def USize.toUInt64 (u : USize) : UInt64 where
+  toBitVec := BitVec.ofNatLt u.toBitVec.toNat (
+        let ⟨⟨n, h⟩⟩ := u
+        show LT.lt n _ from
+        match System.Platform.numBits, System.Platform.numBits_eq, h with
+        | _, Or.inl rfl, h => Nat.lt_trans h (of_decide_eq_true rfl)
+        | _, Or.inr rfl, h => h
+      )
+
 /-- An opaque hash mixing operation, used to implement hashing for tuples. -/
 @[extern "lean_uint64_mix_hash"]
 opaque mixHash (u₁ u₂ : UInt64) : UInt64
@@ -3623,8 +3654,7 @@ namespace SourceInfo
 
 /--
 Gets the position information from a `SourceInfo`, if available.
-If `canonicalOnly` is true, then `.synthetic` syntax with `canonical := false`
-will also return `none`.
+If `originalOnly` is true, then `.synthetic` syntax will also return `none`.
 -/
 def getPos? (info : SourceInfo) (canonicalOnly := false) : Option String.Pos :=
   match info, canonicalOnly with
@@ -3635,8 +3665,7 @@ def getPos? (info : SourceInfo) (canonicalOnly := false) : Option String.Pos :=
 
 /--
 Gets the end position information from a `SourceInfo`, if available.
-If `canonicalOnly` is true, then `.synthetic` syntax with `canonical := false`
-will also return `none`.
+If `originalOnly` is true, then `.synthetic` syntax will also return `none`.
 -/
 def getTailPos? (info : SourceInfo) (canonicalOnly := false) : Option String.Pos :=
   match info, canonicalOnly with
@@ -3645,24 +3674,6 @@ def getTailPos? (info : SourceInfo) (canonicalOnly := false) : Option String.Pos
   | synthetic (endPos := endPos) .., false => some endPos
   | _,                               _     => none
 
-/--
-Gets the substring representing the trailing whitespace of a `SourceInfo`, if available.
--/
-def getTrailing? (info : SourceInfo) : Option Substring :=
-  match info with
-  | original (trailing := trailing) .. => some trailing
-  | _                                  => none
-
-/--
-Gets the end position information of the trailing whitespace of a `SourceInfo`, if available.
-If `canonicalOnly` is true, then `.synthetic` syntax with `canonical := false`
-will also return `none`.
--/
-def getTrailingTailPos? (info : SourceInfo) (canonicalOnly := false) : Option String.Pos :=
-  match info.getTrailing? with
-  | some trailing => some trailing.stopPos
-  | none          => info.getTailPos? canonicalOnly
-
 end SourceInfo
 
 /--
@@ -3961,6 +3972,7 @@ position information.
 def getPos? (stx : Syntax) (canonicalOnly := false) : Option String.Pos :=
   stx.getHeadInfo.getPos? canonicalOnly
 
+
 /--
 Get the ending position of the syntax, if possible.
 If `canonicalOnly` is true, non-canonical `synthetic` nodes are treated as not carrying

src/Init/PropLemmas.lean

@@ -386,15 +386,6 @@ theorem exists_comm {p : α → β → Prop} : (∃ a b, p a b) ↔ (∃ b a, p
 theorem forall_prop_of_false {p : Prop} {q : p → Prop} (hn : ¬p) : (∀ h' : p, q h') ↔ True :=
   iff_true_intro fun h => hn.elim h
 
-@[simp] theorem and_exists_self (P : Prop) (Q : P → Prop) : (P ∧ ∃ p, Q p) ↔ ∃ p, Q p :=
-  ⟨fun ⟨_, h⟩ => h, fun ⟨p, q⟩ => ⟨p, ⟨p, q⟩⟩⟩
-
-@[simp] theorem exists_and_self (P : Prop) (Q : P → Prop) : ((∃ p, Q p) ∧ P) ↔ ∃ p, Q p :=
-  ⟨fun ⟨h, _⟩ => h, fun ⟨p, q⟩ => ⟨⟨p, q⟩, p⟩⟩
-
-@[simp] theorem forall_self_imp (P : Prop) (Q : P → Prop) : (∀ p : P, P → Q p) ↔ ∀ p, Q p :=
-  ⟨fun h p => h p p, fun h _ p => h p⟩
-
 end quantifiers
 
 /-! ## membership -/

src/Init/ShareCommon.lean

@@ -5,7 +5,6 @@ Authors: Leonardo de Moura, Mario Carneiro
 -/
 prelude
 import Init.Util
-import Init.Data.UInt.Basic
 
 namespace ShareCommon
 /-

src/Init/SimpLemmas.lean

@@ -72,21 +72,6 @@ theorem let_body_congr {α : Sort u} {β : α → Sort v} {b b' : (a : α) →
     (a : α) (h : ∀ x, b x = b' x) : (let x := a; b x) = (let x := a; b' x) :=
   (funext h : b = b') ▸ rfl
 
-theorem letFun_unused {α : Sort u} {β : Sort v} (a : α) {b b' : β} (h : b = b') : @letFun α (fun _ => β) a (fun _ => b) = b' :=
-  h
-
-theorem letFun_congr {α : Sort u} {β : Sort v}  {a a' : α} {f f' : α → β} (h₁ : a = a') (h₂ : ∀ x, f x = f' x)
-    : @letFun α (fun _ => β) a f = @letFun α (fun _ => β) a' f' := by
-  rw [h₁, funext h₂]
-
-theorem letFun_body_congr {α : Sort u} {β : Sort v}  (a : α) {f f' : α → β} (h : ∀ x, f x = f' x)
-    : @letFun α (fun _ => β) a f = @letFun α (fun _ => β) a f' := by
-  rw [funext h]
-
-theorem letFun_val_congr {α : Sort u} {β : Sort v} {a a' : α} {f : α → β} (h : a = a')
-    : @letFun α (fun _ => β) a f = @letFun α (fun _ => β) a' f := by
-  rw [h]
-
 @[congr]
 theorem ite_congr {x y u v : α} {s : Decidable b} [Decidable c]
     (h₁ : b = c) (h₂ : c → x = u) (h₃ : ¬ c → y = v) : ite b x y = ite c u v := by

src/Init/Syntax.lean

@@ -30,7 +30,7 @@ Does nothing for non-`node` nodes, or if `i` is out of bounds of the node list.
 -/
 def setArg (stx : Syntax) (i : Nat) (arg : Syntax) : Syntax :=
   match stx with
-  | node info k args => node info k (args.setIfInBounds i arg)
+  | node info k args => node info k (args.setD i arg)
   | stx              => stx
 
 end Lean.Syntax

src/Init/System/IO.lean

@@ -462,16 +462,6 @@ Note that it is the caller's job to remove the file after use.
 -/
 @[extern "lean_io_create_tempfile"] opaque createTempFile : IO (Handle × FilePath)
 
-/--
-Creates a temporary directory in the most secure manner possible. There are no race conditions in the
-directory’s creation. The directory is readable and writable only by the creating user ID.
-
-Returns the new directory's path.
-
-It is the caller's job to remove the directory after use.
--/
-@[extern "lean_io_create_tempdir"] opaque createTempDir : IO FilePath
-
 end FS
 
 @[extern "lean_io_getenv"] opaque getEnv (var : @& String) : BaseIO (Option String)
@@ -484,6 +474,17 @@ namespace FS
 def withFile (fn : FilePath) (mode : Mode) (f : Handle → IO α) : IO α :=
   Handle.mk fn mode >>= f
 
+/--
+Like `createTempFile` but also takes care of removing the file after usage.
+-/
+def withTempFile [Monad m] [MonadFinally m] [MonadLiftT IO m] (f : Handle → FilePath → m α) :
+    m α := do
+  let (handle, path) ← createTempFile
+  try
+    f handle path
+  finally
+    removeFile path
+
 def Handle.putStrLn (h : Handle) (s : String) : IO Unit :=
   h.putStr (s.push '\n')
 
@@ -674,10 +675,8 @@ def appDir : IO FilePath := do
     | throw <| IO.userError s!"System.IO.appDir: unexpected filename '{p}'"
   FS.realPath p
 
-namespace FS
-
 /-- Create given path and all missing parents as directories. -/
-partial def createDirAll (p : FilePath) : IO Unit := do
+partial def FS.createDirAll (p : FilePath) : IO Unit := do
   if ← p.isDir then
     return ()
   if let some parent := p.parent then
@@ -694,7 +693,7 @@ partial def createDirAll (p : FilePath) : IO Unit := do
 /--
   Fully remove given directory by deleting all contained files and directories in an unspecified order.
   Fails if any contained entry cannot be deleted or was newly created during execution. -/
-partial def removeDirAll (p : FilePath) : IO Unit := do
+partial def FS.removeDirAll (p : FilePath) : IO Unit := do
   for ent in (← p.readDir) do
     if (← ent.path.isDir : Bool) then
       removeDirAll ent.path
@@ -702,32 +701,6 @@ partial def removeDirAll (p : FilePath) : IO Unit := do
       removeFile ent.path
   removeDir p
 
-/--
-Like `createTempFile`, but also takes care of removing the file after usage.
--/
-def withTempFile [Monad m] [MonadFinally m] [MonadLiftT IO m] (f : Handle → FilePath → m α) :
-    m α := do
-  let (handle, path) ← createTempFile
-  try
-    f handle path
-  finally
-    removeFile path
-
-/--
-Like `createTempDir`, but also takes care of removing the directory after usage.
-
-All files in the directory are recursively deleted, regardless of how or when they were created.
--/
-def withTempDir [Monad m] [MonadFinally m] [MonadLiftT IO m] (f : FilePath → m α) :
-    m α := do
-  let path ← createTempDir
-  try
-    f path
-  finally
-    removeDirAll path
-
-end FS
-
 namespace Process
 
 /-- Returns the current working directory of the calling process. -/
@@ -959,36 +932,3 @@ syntax "println! " (interpolatedStr(term) <|> term) : term
 macro_rules
   | `(println! $msg:interpolatedStr) => `((IO.println (s! $msg) : IO Unit))
   | `(println! $msg:term)            => `((IO.println $msg : IO Unit))
-
-/--
-  Marks given value and its object graph closure as multi-threaded if currently
-  marked single-threaded. This will make reference counter updates atomic and
-  thus more costly. It can still be useful to do eagerly when the value will be
-  shared between threads later anyway and there is available time budget to mark
-  it now. -/
-@[extern "lean_runtime_mark_multi_threaded"]
-def Runtime.markMultiThreaded (a : α) : BaseIO α := return a
-
-/--
-Marks given value and its object graph closure as persistent. This will remove
-reference counter updates but prevent the closure from being deallocated until
-the end of the process! It can still be useful to do eagerly when the value
-will be marked persistent later anyway and there is available time budget to
-mark it now or it would be unnecessarily marked multi-threaded in between.
-
-This function is only safe to use on objects (in the full closure) which are
-not used concurrently or which are already persistent.
--/
-@[extern "lean_runtime_mark_persistent"]
-unsafe def Runtime.markPersistent (a : α) : BaseIO α := return a
-
-set_option linter.unusedVariables false in
-/--
-Discards the passed owned reference. This leads to `a` any any object reachable from it never being
-freed. This can be a useful optimization for eliding deallocation time of big object graphs that are
-kept alive close to the end of the process anyway (in which case calling `Runtime.markPersistent`
-would be similarly costly to deallocation). It is still considered a safe operation as it cannot
-lead to undefined behavior.
--/
-@[extern "lean_runtime_forget"]
-def Runtime.forget (a : α) : BaseIO Unit := return

src/Init/System/Mutex.lean

@@ -7,9 +7,6 @@ prelude
 import Init.System.IO
 import Init.Control.StateRef
 
-
-set_option linter.deprecated false
-
 namespace IO
 
 private opaque BaseMutexImpl : NonemptyType.{0}
@@ -19,13 +16,12 @@ Mutual exclusion primitive (a lock).
 
 If you want to guard shared state, use `Mutex α` instead.
 -/
-@[deprecated "Use Std.BaseMutex from Std.Sync.Mutex instead" (since := "2024-12-02")]
 def BaseMutex : Type := BaseMutexImpl.type
 
 instance : Nonempty BaseMutex := BaseMutexImpl.property
 
 /-- Creates a new `BaseMutex`. -/
-@[extern "lean_io_basemutex_new", deprecated "Use Std.BaseMutex.new from Std.Sync.Mutex instead" (since := "2024-12-02")]
+@[extern "lean_io_basemutex_new"]
 opaque BaseMutex.new : BaseIO BaseMutex
 
 /--
@@ -34,7 +30,7 @@ Locks a `BaseMutex`.  Waits until no other thread has locked the mutex.
 The current thread must not have already locked the mutex.
 Reentrant locking is undefined behavior (inherited from the C++ implementation).
 -/
-@[extern "lean_io_basemutex_lock", deprecated "Use Std.BaseMutex.lock from Std.Sync.Mutex instead" (since := "2024-12-02")]
+@[extern "lean_io_basemutex_lock"]
 opaque BaseMutex.lock (mutex : @& BaseMutex) : BaseIO Unit
 
 /--
@@ -43,35 +39,33 @@ Unlocks a `BaseMutex`.
 The current thread must have already locked the mutex.
 Unlocking an unlocked mutex is undefined behavior (inherited from the C++ implementation).
 -/
-@[extern "lean_io_basemutex_unlock", deprecated "Use Std.BaseMutex.unlock from Std.Sync.Mutex instead" (since := "2024-12-02")]
+@[extern "lean_io_basemutex_unlock"]
 opaque BaseMutex.unlock (mutex : @& BaseMutex) : BaseIO Unit
 
 private opaque CondvarImpl : NonemptyType.{0}
 
 /-- Condition variable. -/
-@[deprecated "Use Std.Condvar from Std.Sync.Mutex instead" (since := "2024-12-02")]
 def Condvar : Type := CondvarImpl.type
 
 instance : Nonempty Condvar := CondvarImpl.property
 
 /-- Creates a new condition variable. -/
-@[extern "lean_io_condvar_new", deprecated "Use Std.Condvar.new from Std.Sync.Mutex instead" (since := "2024-12-02")]
+@[extern "lean_io_condvar_new"]
 opaque Condvar.new : BaseIO Condvar
 
 /-- Waits until another thread calls `notifyOne` or `notifyAll`. -/
-@[extern "lean_io_condvar_wait", deprecated "Use Std.Condvar.wait from Std.Sync.Mutex instead" (since := "2024-12-02")]
+@[extern "lean_io_condvar_wait"]
 opaque Condvar.wait (condvar : @& Condvar) (mutex : @& BaseMutex) : BaseIO Unit
 
 /-- Wakes up a single other thread executing `wait`. -/
-@[extern "lean_io_condvar_notify_one", deprecated "Use Std.Condvar.notifyOne from Std.Sync.Mutex instead" (since := "2024-12-02")]
+@[extern "lean_io_condvar_notify_one"]
 opaque Condvar.notifyOne (condvar : @& Condvar) : BaseIO Unit
 
 /-- Wakes up all other threads executing `wait`. -/
-@[extern "lean_io_condvar_notify_all", deprecated "Use Std.Condvar.notifyAll from Std.Sync.Mutex instead" (since := "2024-12-02")]
+@[extern "lean_io_condvar_notify_all"]
 opaque Condvar.notifyAll (condvar : @& Condvar) : BaseIO Unit
 
 /-- Waits on the condition variable until the predicate is true. -/
-@[deprecated "Use Std.Condvar.waitUntil from Std.Sync.Mutex instead" (since := "2024-12-02")]
 def Condvar.waitUntil [Monad m] [MonadLift BaseIO m]
     (condvar : Condvar) (mutex : BaseMutex) (pred : m Bool) : m Unit := do
   while !(← pred) do
@@ -84,7 +78,6 @@ The type `Mutex α` is similar to `IO.Ref α`,
 except that concurrent accesses are guarded by a mutex
 instead of atomic pointer operations and busy-waiting.
 -/
-@[deprecated "Use Std.Mutex from Std.Sync.Mutex instead" (since := "2024-12-02")]
 structure Mutex (α : Type) where private mk ::
   private ref : IO.Ref α
   mutex : BaseMutex
@@ -93,7 +86,6 @@ structure Mutex (α : Type) where private mk ::
 instance : CoeOut (Mutex α) BaseMutex where coe := Mutex.mutex
 
 /-- Creates a new mutex. -/
-@[deprecated "Use Std.Mutex.new from Std.Sync.Mutex instead" (since := "2024-12-02")]
 def Mutex.new (a : α) : BaseIO (Mutex α) :=
   return { ref := ← mkRef a, mutex := ← BaseMutex.new }
 
@@ -102,11 +94,9 @@ def Mutex.new (a : α) : BaseIO (Mutex α) :=
 with outside monad `m`.
 The action has access to the state `α` of the mutex (via `get` and `set`).
 -/
-@[deprecated "Use Std.AtomicT from Std.Sync.Mutex instead" (since := "2024-12-02")]
 abbrev AtomicT := StateRefT' IO.RealWorld
 
 /-- `mutex.atomically k` runs `k` with access to the mutex's state while locking the mutex. -/
-@[deprecated "Use Std.Mutex.atomically from Std.Sync.Mutex instead" (since := "2024-12-02")]
 def Mutex.atomically [Monad m] [MonadLiftT BaseIO m] [MonadFinally m]
     (mutex : Mutex α) (k : AtomicT α m β) : m β := do
   try
@@ -120,7 +110,6 @@ def Mutex.atomically [Monad m] [MonadLiftT BaseIO m] [MonadFinally m]
 waiting on `condvar` until `pred` returns true.
 Both `k` and `pred` have access to the mutex's state.
 -/
-@[deprecated "Use Std.Mutex.atomicallyOnce from Std.Sync.Mutex instead" (since := "2024-12-02")]
 def Mutex.atomicallyOnce [Monad m] [MonadLiftT BaseIO m] [MonadFinally m]
     (mutex : Mutex α) (condvar : Condvar)
     (pred : AtomicT α m Bool) (k : AtomicT α m β) : m β :=

src/Init/System/Platform.lean

@@ -23,14 +23,5 @@ def isEmscripten : Bool := getIsEmscripten ()
 /-- The LLVM target triple of the current platform. Empty if missing at Lean compile time. -/
 def target : String := getTarget ()
 
-theorem numBits_pos : 0 < numBits := by
-  cases numBits_eq <;> next h => simp [h]
-
-theorem le_numBits : 32 ≤ numBits := by
-  cases numBits_eq <;> next h => simp [h]
-
-theorem numBits_le : numBits ≤ 64 := by
-  cases numBits_eq <;> next h => simp [h]
-
 end Platform
 end System