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Author SHA1 Message Date
Kim Morrison
1739bcaa38 chore: cleanup of Array docstrings after refactor 2024-09-25 08:59:55 +10:00
1674 changed files with 7062 additions and 28818 deletions

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

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@@ -11,9 +11,7 @@ jobs:
with:
# the default is to use a virtual merge commit between the PR and master: just use the PR
ref: ${{ github.event.pull_request.head.sha }}
sparse-checkout: |
src/Lean
src/Std
sparse-checkout: src/Lean
- name: Check Prelude
run: |
failed_files=""
@@ -21,8 +19,8 @@ jobs:
if ! grep -q "^prelude$" "$file"; then
failed_files="$failed_files$file\n"
fi
done < <(find src/Lean src/Std -name '*.lean' -print0)
done < <(find src/Lean -name '*.lean' -print0)
if [ -n "$failed_files" ]; then
echo -e "The following files should use 'prelude':\n$failed_files"
exit 1
fi
fi

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@@ -217,7 +217,7 @@ jobs:
"release": true,
"check-level": 2,
"shell": "msys2 {0}",
"CMAKE_OPTIONS": "-G \"Unix Makefiles\"",
"CMAKE_OPTIONS": "-G \"Unix Makefiles\" -DUSE_GMP=OFF",
// for reasons unknown, interactivetests are flaky on Windows
"CTEST_OPTIONS": "--repeat until-pass:2",
"llvm-url": "https://github.com/leanprover/lean-llvm/releases/download/15.0.1/lean-llvm-x86_64-w64-windows-gnu.tar.zst",
@@ -227,7 +227,7 @@ jobs:
{
"name": "Linux aarch64",
"os": "nscloud-ubuntu-22.04-arm64-4x8",
"CMAKE_OPTIONS": "-DLEAN_INSTALL_SUFFIX=-linux_aarch64",
"CMAKE_OPTIONS": "-DUSE_GMP=OFF -DLEAN_INSTALL_SUFFIX=-linux_aarch64",
"release": true,
"check-level": 2,
"shell": "nix develop .#oldGlibcAArch -c bash -euxo pipefail {0}",
@@ -257,7 +257,7 @@ jobs:
"cross": true,
"shell": "bash -euxo pipefail {0}",
// Just a few selected tests because wasm is slow
"CTEST_OPTIONS": "-R \"leantest_1007\\.lean|leantest_Format\\.lean|leanruntest\\_1037.lean|leanruntest_ac_rfl\\.lean|leanruntest_tempfile.lean\\.|leanruntest_libuv\\.lean\""
"CTEST_OPTIONS": "-R \"leantest_1007\\.lean|leantest_Format\\.lean|leanruntest\\_1037.lean|leanruntest_ac_rfl\\.lean|leanruntest_libuv\\.lean\""
}
];
console.log(`matrix:\n${JSON.stringify(matrix, null, 2)}`)
@@ -452,7 +452,7 @@ jobs:
run: ccache -s
# This job collects results from all the matrix jobs
# This can be made the "required" job, instead of listing each
# This can be made the required job, instead of listing each
# matrix job separately
all-done:
name: Build matrix complete

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@@ -96,7 +96,7 @@ jobs:
nix build $NIX_BUILD_ARGS .#cacheRoots -o push-build
- name: Test
run: |
nix build --keep-failed $NIX_BUILD_ARGS .#test -o push-test || (ln -s /tmp/nix-build-*/build/source/src/build ./push-test; false)
nix build --keep-failed $NIX_BUILD_ARGS .#test -o push-test || (ln -s /tmp/nix-build-*/source/src/build/ ./push-test; false)
- name: Test Summary
uses: test-summary/action@v2
with:

View File

@@ -164,10 +164,10 @@ jobs:
# Use GitHub API to check if a comment already exists
existing_comment="$(curl --retry 3 --location --silent \
-H "Authorization: token ${{ secrets.MATHLIB4_COMMENT_BOT }}" \
-H "Authorization: token ${{ secrets.MATHLIB4_BOT }}" \
-H "Accept: application/vnd.github.v3+json" \
"https://api.github.com/repos/leanprover/lean4/issues/${{ steps.workflow-info.outputs.pullRequestNumber }}/comments" \
| jq 'first(.[] | select(.body | test("^- . Mathlib") or startswith("Mathlib CI status")) | select(.user.login == "leanprover-community-bot"))')"
| jq 'first(.[] | select(.body | test("^- . Mathlib") or startswith("Mathlib CI status")) | select(.user.login == "leanprover-community-mathlib4-bot"))')"
existing_comment_id="$(echo "$existing_comment" | jq -r .id)"
existing_comment_body="$(echo "$existing_comment" | jq -r .body)"
@@ -177,14 +177,14 @@ jobs:
echo "Posting message to the comments: $MESSAGE"
# Append new result to the existing comment or post a new comment
# It's essential we use the MATHLIB4_COMMENT_BOT token here, so that Mathlib CI can subsequently edit the comment.
# It's essential we use the MATHLIB4_BOT token here, so that Mathlib CI can subsequently edit the comment.
if [ -z "$existing_comment_id" ]; then
INTRO="Mathlib CI status ([docs](https://leanprover-community.github.io/contribute/tags_and_branches.html)):"
# Post new comment with a bullet point
echo "Posting as new comment at leanprover/lean4/issues/${{ steps.workflow-info.outputs.pullRequestNumber }}/comments"
curl -L -s \
-X POST \
-H "Authorization: token ${{ secrets.MATHLIB4_COMMENT_BOT }}" \
-H "Authorization: token ${{ secrets.MATHLIB4_BOT }}" \
-H "Accept: application/vnd.github.v3+json" \
-d "$(jq --null-input --arg intro "$INTRO" --arg val "$MESSAGE" '{"body":($intro + "\n" + $val)}')" \
"https://api.github.com/repos/leanprover/lean4/issues/${{ steps.workflow-info.outputs.pullRequestNumber }}/comments"
@@ -193,7 +193,7 @@ jobs:
echo "Appending to existing comment at leanprover/lean4/issues/${{ steps.workflow-info.outputs.pullRequestNumber }}/comments"
curl -L -s \
-X PATCH \
-H "Authorization: token ${{ secrets.MATHLIB4_COMMENT_BOT }}" \
-H "Authorization: token ${{ secrets.MATHLIB4_BOT }}" \
-H "Accept: application/vnd.github.v3+json" \
-d "$(jq --null-input --arg existing "$existing_comment_body" --arg message "$MESSAGE" '{"body":($existing + "\n" + $message)}')" \
"https://api.github.com/repos/leanprover/lean4/issues/comments/$existing_comment_id"
@@ -340,7 +340,6 @@ jobs:
# (This should no longer be possible once `nightly-testing-YYYY-MM-DD` is a tag, but it is still safe to merge.)
git merge "$BASE" --strategy-option ours --no-commit --allow-unrelated-histories
lake update batteries
git add lake-manifest.json
git commit --allow-empty -m "Trigger CI for https://github.com/leanprover/lean4/pull/${{ steps.workflow-info.outputs.pullRequestNumber }}"
fi

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@@ -4,14 +4,14 @@
# Listed persons will automatically be asked by GitHub to review a PR touching these paths.
# If multiple names are listed, a review by any of them is considered sufficient by default.
/.github/ @Kha @kim-em
/RELEASES.md @kim-em
/.github/ @Kha @semorrison
/RELEASES.md @semorrison
/src/kernel/ @leodemoura
/src/lake/ @tydeu
/src/Lean/Compiler/ @leodemoura
/src/Lean/Data/Lsp/ @mhuisi
/src/Lean/Elab/Deriving/ @kim-em
/src/Lean/Elab/Tactic/ @kim-em
/src/Lean/Elab/Deriving/ @semorrison
/src/Lean/Elab/Tactic/ @semorrison
/src/Lean/Language/ @Kha
/src/Lean/Meta/Tactic/ @leodemoura
/src/Lean/Parser/ @Kha
@@ -19,7 +19,7 @@
/src/Lean/PrettyPrinter/Delaborator/ @kmill
/src/Lean/Server/ @mhuisi
/src/Lean/Widget/ @Vtec234
/src/Init/Data/ @kim-em
/src/Init/Data/ @semorrison
/src/Init/Data/Array/Lemmas.lean @digama0
/src/Init/Data/List/Lemmas.lean @digama0
/src/Init/Data/List/BasicAux.lean @digama0
@@ -45,4 +45,3 @@
/src/Std/ @TwoFX
/src/Std/Tactic/BVDecide/ @hargoniX
/src/Lean/Elab/Tactic/BVDecide/ @hargoniX
/src/Std/Sat/ @hargoniX

View File

@@ -8,642 +8,9 @@ This file contains work-in-progress notes for the upcoming release, as well as p
Please check the [releases](https://github.com/leanprover/lean4/releases) page for the current status
of each version.
v4.15.0
----------
Development in progress.
v4.14.0
----------
Release candidate, release notes will be copied from the branch `releases/v4.14.0` once completed.
v4.13.0
----------
**Full Changelog**: https://github.com/leanprover/lean4/compare/v4.12.0...v4.13.0
### Language features, tactics, and metaprograms
* `structure` command
* [#5511](https://github.com/leanprover/lean4/pull/5511) allows structure parents to be type synonyms.
* [#5531](https://github.com/leanprover/lean4/pull/5531) allows default values for structure fields to be noncomputable.
* `rfl` and `apply_rfl` tactics
* [#3714](https://github.com/leanprover/lean4/pull/3714), [#3718](https://github.com/leanprover/lean4/pull/3718) improve the `rfl` tactic and give better error messages.
* [#3772](https://github.com/leanprover/lean4/pull/3772) makes `rfl` no longer use kernel defeq for ground terms.
* [#5329](https://github.com/leanprover/lean4/pull/5329) tags `Iff.refl` with `@[refl]` (@Parcly-Taxel)
* [#5359](https://github.com/leanprover/lean4/pull/5359) ensures that the `rfl` tactic tries `Iff.rfl` (@Parcly-Taxel)
* `unfold` tactic
* [#4834](https://github.com/leanprover/lean4/pull/4834) let `unfold` do zeta-delta reduction of local definitions, incorporating functionality of the Mathlib `unfold_let` tactic.
* `omega` tactic
* [#5382](https://github.com/leanprover/lean4/pull/5382) fixes spurious error in [#5315](https://github.com/leanprover/lean4/issues/5315)
* [#5523](https://github.com/leanprover/lean4/pull/5523) supports `Int.toNat`
* `simp` tactic
* [#5479](https://github.com/leanprover/lean4/pull/5479) lets `simp` apply rules with higher-order patterns.
* `induction` tactic
* [#5494](https://github.com/leanprover/lean4/pull/5494) fixes `induction`s "pre-tactic" block to always be indented, avoiding unintended uses of it.
* `ac_nf` tactic
* [#5524](https://github.com/leanprover/lean4/pull/5524) adds `ac_nf`, a counterpart to `ac_rfl`, for normalizing expressions with respect to associativity and commutativity. Tests it with `BitVec` expressions.
* `bv_decide`
* [#5211](https://github.com/leanprover/lean4/pull/5211) makes `extractLsb'` the primitive `bv_decide` understands, rather than `extractLsb` (@alexkeizer)
* [#5365](https://github.com/leanprover/lean4/pull/5365) adds `bv_decide` diagnoses.
* [#5375](https://github.com/leanprover/lean4/pull/5375) adds `bv_decide` normalization rules for `ofBool (a.getLsbD i)` and `ofBool a[i]` (@alexkeizer)
* [#5423](https://github.com/leanprover/lean4/pull/5423) enhances the rewriting rules of `bv_decide`
* [#5433](https://github.com/leanprover/lean4/pull/5433) presents the `bv_decide` counterexample at the API
* [#5484](https://github.com/leanprover/lean4/pull/5484) handles `BitVec.ofNat` with `Nat` fvars in `bv_decide`
* [#5506](https://github.com/leanprover/lean4/pull/5506), [#5507](https://github.com/leanprover/lean4/pull/5507) add `bv_normalize` rules.
* [#5568](https://github.com/leanprover/lean4/pull/5568) generalize the `bv_normalize` pipeline to support more general preprocessing passes
* [#5573](https://github.com/leanprover/lean4/pull/5573) gets `bv_normalize` up-to-date with the current `BitVec` rewrites
* Cleanups: [#5408](https://github.com/leanprover/lean4/pull/5408), [#5493](https://github.com/leanprover/lean4/pull/5493), [#5578](https://github.com/leanprover/lean4/pull/5578)
* Elaboration improvements
* [#5266](https://github.com/leanprover/lean4/pull/5266) preserve order of overapplied arguments in `elab_as_elim` procedure.
* [#5510](https://github.com/leanprover/lean4/pull/5510) generalizes `elab_as_elim` to allow arbitrary motive applications.
* [#5283](https://github.com/leanprover/lean4/pull/5283), [#5512](https://github.com/leanprover/lean4/pull/5512) refine how named arguments suppress explicit arguments. Breaking change: some previously omitted explicit arguments may need explicit `_` arguments now.
* [#5376](https://github.com/leanprover/lean4/pull/5376) modifies projection instance binder info for instances, making parameters that are instance implicit in the type be implicit.
* [#5402](https://github.com/leanprover/lean4/pull/5402) localizes universe metavariable errors to `let` bindings and `fun` binders if possible. Makes "cannot synthesize metavariable" errors take precedence over unsolved universe level errors.
* [#5419](https://github.com/leanprover/lean4/pull/5419) must not reduce `ite` in the discriminant of `match`-expression when reducibility setting is `.reducible`
* [#5474](https://github.com/leanprover/lean4/pull/5474) have autoparams report parameter/field on failure
* [#5530](https://github.com/leanprover/lean4/pull/5530) makes automatic instance names about types with hygienic names be hygienic.
* Deriving handlers
* [#5432](https://github.com/leanprover/lean4/pull/5432) makes `Repr` deriving instance handle explicit type parameters
* Functional induction
* [#5364](https://github.com/leanprover/lean4/pull/5364) adds more equalities in context, more careful cleanup.
* Linters
* [#5335](https://github.com/leanprover/lean4/pull/5335) fixes the unused variables linter complaining about match/tactic combinations
* [#5337](https://github.com/leanprover/lean4/pull/5337) fixes the unused variables linter complaining about some wildcard patterns
* Other fixes
* [#4768](https://github.com/leanprover/lean4/pull/4768) fixes a parse error when `..` appears with a `.` on the next line
* Metaprogramming
* [#3090](https://github.com/leanprover/lean4/pull/3090) handles level parameters in `Meta.evalExpr` (@eric-wieser)
* [#5401](https://github.com/leanprover/lean4/pull/5401) instance for `Inhabited (TacticM α)` (@alexkeizer)
* [#5412](https://github.com/leanprover/lean4/pull/5412) expose Kernel.check for debugging purposes
* [#5556](https://github.com/leanprover/lean4/pull/5556) improves the "invalid projection" type inference error in `inferType`.
* [#5587](https://github.com/leanprover/lean4/pull/5587) allows `MVarId.assertHypotheses` to set `BinderInfo` and `LocalDeclKind`.
* [#5588](https://github.com/leanprover/lean4/pull/5588) adds `MVarId.tryClearMany'`, a variant of `MVarId.tryClearMany`.
### Language server, widgets, and IDE extensions
* [#5205](https://github.com/leanprover/lean4/pull/5205) decreases the latency of auto-completion in tactic blocks.
* [#5237](https://github.com/leanprover/lean4/pull/5237) fixes symbol occurrence highlighting in VS Code not highlighting occurrences when moving the text cursor into the identifier from the right.
* [#5257](https://github.com/leanprover/lean4/pull/5257) fixes several instances of incorrect auto-completions being reported.
* [#5299](https://github.com/leanprover/lean4/pull/5299) allows auto-completion to report completions for global identifiers when the elaborator fails to provide context-specific auto-completions.
* [#5312](https://github.com/leanprover/lean4/pull/5312) fixes the server breaking when changing whitespace after the module header.
* [#5322](https://github.com/leanprover/lean4/pull/5322) fixes several instances of auto-completion reporting non-existent namespaces.
* [#5428](https://github.com/leanprover/lean4/pull/5428) makes sure to always report some recent file range as progress when waiting for elaboration.
### Pretty printing
* [#4979](https://github.com/leanprover/lean4/pull/4979) make pretty printer escape identifiers that are tokens.
* [#5389](https://github.com/leanprover/lean4/pull/5389) makes formatter use the current token table.
* [#5513](https://github.com/leanprover/lean4/pull/5513) use breakable instead of unbreakable whitespace when formatting tokens.
### Library
* [#5222](https://github.com/leanprover/lean4/pull/5222) reduces allocations in `Json.compress`.
* [#5231](https://github.com/leanprover/lean4/pull/5231) upstreams `Zero` and `NeZero`
* [#5292](https://github.com/leanprover/lean4/pull/5292) refactors `Lean.Elab.Deriving.FromToJson` (@arthur-adjedj)
* [#5415](https://github.com/leanprover/lean4/pull/5415) implements `Repr Empty` (@TomasPuverle)
* [#5421](https://github.com/leanprover/lean4/pull/5421) implements `To/FromJSON Empty` (@TomasPuverle)
* Logic
* [#5263](https://github.com/leanprover/lean4/pull/5263) allows simplifying `dite_not`/`decide_not` with only `Decidable (¬p)`.
* [#5268](https://github.com/leanprover/lean4/pull/5268) fixes binders on `ite_eq_left_iff`
* [#5284](https://github.com/leanprover/lean4/pull/5284) turns off `Inhabited (Sum α β)` instances
* [#5355](https://github.com/leanprover/lean4/pull/5355) adds simp lemmas for `LawfulBEq`
* [#5374](https://github.com/leanprover/lean4/pull/5374) add `Nonempty` instances for products, allowing more `partial` functions to elaborate successfully
* [#5447](https://github.com/leanprover/lean4/pull/5447) updates Pi instance names
* [#5454](https://github.com/leanprover/lean4/pull/5454) makes some instance arguments implicit
* [#5456](https://github.com/leanprover/lean4/pull/5456) adds `heq_comm`
* [#5529](https://github.com/leanprover/lean4/pull/5529) moves `@[simp]` from `exists_prop'` to `exists_prop`
* `Bool`
* [#5228](https://github.com/leanprover/lean4/pull/5228) fills gaps in Bool lemmas
* [#5332](https://github.com/leanprover/lean4/pull/5332) adds notation `^^` for Bool.xor
* [#5351](https://github.com/leanprover/lean4/pull/5351) removes `_root_.and` (and or/not/xor) and instead exports/uses `Bool.and` (etc.).
* `BitVec`
* [#5240](https://github.com/leanprover/lean4/pull/5240) removes BitVec simps with complicated RHS
* [#5247](https://github.com/leanprover/lean4/pull/5247) `BitVec.getElem_zeroExtend`
* [#5248](https://github.com/leanprover/lean4/pull/5248) simp lemmas for BitVec, improving confluence
* [#5249](https://github.com/leanprover/lean4/pull/5249) removes `@[simp]` from some BitVec lemmas
* [#5252](https://github.com/leanprover/lean4/pull/5252) changes `BitVec.intMin/Max` from abbrev to def
* [#5278](https://github.com/leanprover/lean4/pull/5278) adds `BitVec.getElem_truncate` (@tobiasgrosser)
* [#5281](https://github.com/leanprover/lean4/pull/5281) adds udiv/umod bitblasting for `bv_decide` (@bollu)
* [#5297](https://github.com/leanprover/lean4/pull/5297) `BitVec` unsigned order theoretic results
* [#5313](https://github.com/leanprover/lean4/pull/5313) adds more basic BitVec ordering theory for UInt
* [#5314](https://github.com/leanprover/lean4/pull/5314) adds `toNat_sub_of_le` (@bollu)
* [#5357](https://github.com/leanprover/lean4/pull/5357) adds `BitVec.truncate` lemmas
* [#5358](https://github.com/leanprover/lean4/pull/5358) introduces `BitVec.setWidth` to unify zeroExtend and truncate (@tobiasgrosser)
* [#5361](https://github.com/leanprover/lean4/pull/5361) some BitVec GetElem lemmas
* [#5385](https://github.com/leanprover/lean4/pull/5385) adds `BitVec.ofBool_[and|or|xor]_ofBool` theorems (@tobiasgrosser)
* [#5404](https://github.com/leanprover/lean4/pull/5404) more of `BitVec.getElem_*` (@tobiasgrosser)
* [#5410](https://github.com/leanprover/lean4/pull/5410) BitVec analogues of `Nat.{mul_two, two_mul, mul_succ, succ_mul}` (@bollu)
* [#5411](https://github.com/leanprover/lean4/pull/5411) `BitVec.toNat_{add,sub,mul_of_lt}` for BitVector non-overflow reasoning (@bollu)
* [#5413](https://github.com/leanprover/lean4/pull/5413) adds `_self`, `_zero`, and `_allOnes` for `BitVec.[and|or|xor]` (@tobiasgrosser)
* [#5416](https://github.com/leanprover/lean4/pull/5416) adds LawCommIdentity + IdempotentOp for `BitVec.[and|or|xor]` (@tobiasgrosser)
* [#5418](https://github.com/leanprover/lean4/pull/5418) decidable quantifers for BitVec
* [#5450](https://github.com/leanprover/lean4/pull/5450) adds `BitVec.toInt_[intMin|neg|neg_of_ne_intMin]` (@tobiasgrosser)
* [#5459](https://github.com/leanprover/lean4/pull/5459) missing BitVec lemmas
* [#5469](https://github.com/leanprover/lean4/pull/5469) adds `BitVec.[not_not, allOnes_shiftLeft_or_shiftLeft, allOnes_shiftLeft_and_shiftLeft]` (@luisacicolini)
* [#5478](https://github.com/leanprover/lean4/pull/5478) adds `BitVec.(shiftLeft_add_distrib, shiftLeft_ushiftRight)` (@luisacicolini)
* [#5487](https://github.com/leanprover/lean4/pull/5487) adds `sdiv_eq`, `smod_eq` to allow `sdiv`/`smod` bitblasting (@bollu)
* [#5491](https://github.com/leanprover/lean4/pull/5491) adds `BitVec.toNat_[abs|sdiv|smod]` (@tobiasgrosser)
* [#5492](https://github.com/leanprover/lean4/pull/5492) `BitVec.(not_sshiftRight, not_sshiftRight_not, getMsb_not, msb_not)` (@luisacicolini)
* [#5499](https://github.com/leanprover/lean4/pull/5499) `BitVec.Lemmas` - drop non-terminal simps (@tobiasgrosser)
* [#5505](https://github.com/leanprover/lean4/pull/5505) unsimps `BitVec.divRec_succ'`
* [#5508](https://github.com/leanprover/lean4/pull/5508) adds `BitVec.getElem_[add|add_add_bool|mul|rotateLeft|rotateRight…` (@tobiasgrosser)
* [#5554](https://github.com/leanprover/lean4/pull/5554) adds `Bitvec.[add, sub, mul]_eq_xor` and `width_one_cases` (@luisacicolini)
* `List`
* [#5242](https://github.com/leanprover/lean4/pull/5242) improve naming for `List.mergeSort` lemmas
* [#5302](https://github.com/leanprover/lean4/pull/5302) provide `mergeSort` comparator autoParam
* [#5373](https://github.com/leanprover/lean4/pull/5373) fix name of `List.length_mergeSort`
* [#5377](https://github.com/leanprover/lean4/pull/5377) upstream `map_mergeSort`
* [#5378](https://github.com/leanprover/lean4/pull/5378) modify signature of lemmas about `mergeSort`
* [#5245](https://github.com/leanprover/lean4/pull/5245) avoid importing `List.Basic` without List.Impl
* [#5260](https://github.com/leanprover/lean4/pull/5260) review of List API
* [#5264](https://github.com/leanprover/lean4/pull/5264) review of List API
* [#5269](https://github.com/leanprover/lean4/pull/5269) remove HashMap's duplicated Pairwise and Sublist
* [#5271](https://github.com/leanprover/lean4/pull/5271) remove @[simp] from `List.head_mem` and similar
* [#5273](https://github.com/leanprover/lean4/pull/5273) lemmas about `List.attach`
* [#5275](https://github.com/leanprover/lean4/pull/5275) reverse direction of `List.tail_map`
* [#5277](https://github.com/leanprover/lean4/pull/5277) more `List.attach` lemmas
* [#5285](https://github.com/leanprover/lean4/pull/5285) `List.count` lemmas
* [#5287](https://github.com/leanprover/lean4/pull/5287) use boolean predicates in `List.filter`
* [#5289](https://github.com/leanprover/lean4/pull/5289) `List.mem_ite_nil_left` and analogues
* [#5293](https://github.com/leanprover/lean4/pull/5293) cleanup of `List.findIdx` / `List.take` lemmas
* [#5294](https://github.com/leanprover/lean4/pull/5294) switch primes on `List.getElem_take`
* [#5300](https://github.com/leanprover/lean4/pull/5300) more `List.findIdx` theorems
* [#5310](https://github.com/leanprover/lean4/pull/5310) fix `List.all/any` lemmas
* [#5311](https://github.com/leanprover/lean4/pull/5311) fix `List.countP` lemmas
* [#5316](https://github.com/leanprover/lean4/pull/5316) `List.tail` lemma
* [#5331](https://github.com/leanprover/lean4/pull/5331) fix implicitness of `List.getElem_mem`
* [#5350](https://github.com/leanprover/lean4/pull/5350) `List.replicate` lemmas
* [#5352](https://github.com/leanprover/lean4/pull/5352) `List.attachWith` lemmas
* [#5353](https://github.com/leanprover/lean4/pull/5353) `List.head_mem_head?`
* [#5360](https://github.com/leanprover/lean4/pull/5360) lemmas about `List.tail`
* [#5391](https://github.com/leanprover/lean4/pull/5391) review of `List.erase` / `List.find` lemmas
* [#5392](https://github.com/leanprover/lean4/pull/5392) `List.fold` / `attach` lemmas
* [#5393](https://github.com/leanprover/lean4/pull/5393) `List.fold` relators
* [#5394](https://github.com/leanprover/lean4/pull/5394) lemmas about `List.maximum?`
* [#5403](https://github.com/leanprover/lean4/pull/5403) theorems about `List.toArray`
* [#5405](https://github.com/leanprover/lean4/pull/5405) reverse direction of `List.set_map`
* [#5448](https://github.com/leanprover/lean4/pull/5448) add lemmas about `List.IsPrefix` (@Command-Master)
* [#5460](https://github.com/leanprover/lean4/pull/5460) missing `List.set_replicate_self`
* [#5518](https://github.com/leanprover/lean4/pull/5518) rename `List.maximum?` to `max?`
* [#5519](https://github.com/leanprover/lean4/pull/5519) upstream `List.fold` lemmas
* [#5520](https://github.com/leanprover/lean4/pull/5520) restore `@[simp]` on `List.getElem_mem` etc.
* [#5521](https://github.com/leanprover/lean4/pull/5521) List simp fixes
* [#5550](https://github.com/leanprover/lean4/pull/5550) `List.unattach` and simp lemmas
* [#5594](https://github.com/leanprover/lean4/pull/5594) induction-friendly `List.min?_cons`
* `Array`
* [#5246](https://github.com/leanprover/lean4/pull/5246) cleanup imports of Array.Lemmas
* [#5255](https://github.com/leanprover/lean4/pull/5255) split Init.Data.Array.Lemmas for better bootstrapping
* [#5288](https://github.com/leanprover/lean4/pull/5288) rename `Array.data` to `Array.toList`
* [#5303](https://github.com/leanprover/lean4/pull/5303) cleanup of `List.getElem_append` variants
* [#5304](https://github.com/leanprover/lean4/pull/5304) `Array.not_mem_empty`
* [#5400](https://github.com/leanprover/lean4/pull/5400) reorganization in Array/Basic
* [#5420](https://github.com/leanprover/lean4/pull/5420) make `Array` functions either semireducible or use structural recursion
* [#5422](https://github.com/leanprover/lean4/pull/5422) refactor `DecidableEq (Array α)`
* [#5452](https://github.com/leanprover/lean4/pull/5452) refactor of Array
* [#5458](https://github.com/leanprover/lean4/pull/5458) cleanup of Array docstrings after refactor
* [#5461](https://github.com/leanprover/lean4/pull/5461) restore `@[simp]` on `Array.swapAt!_def`
* [#5465](https://github.com/leanprover/lean4/pull/5465) improve Array GetElem lemmas
* [#5466](https://github.com/leanprover/lean4/pull/5466) `Array.foldX` lemmas
* [#5472](https://github.com/leanprover/lean4/pull/5472) @[simp] lemmas about `List.toArray`
* [#5485](https://github.com/leanprover/lean4/pull/5485) reverse simp direction for `toArray_concat`
* [#5514](https://github.com/leanprover/lean4/pull/5514) `Array.eraseReps`
* [#5515](https://github.com/leanprover/lean4/pull/5515) upstream `Array.qsortOrd`
* [#5516](https://github.com/leanprover/lean4/pull/5516) upstream `Subarray.empty`
* [#5526](https://github.com/leanprover/lean4/pull/5526) fix name of `Array.length_toList`
* [#5527](https://github.com/leanprover/lean4/pull/5527) reduce use of deprecated lemmas in Array
* [#5534](https://github.com/leanprover/lean4/pull/5534) cleanup of Array GetElem lemmas
* [#5536](https://github.com/leanprover/lean4/pull/5536) fix `Array.modify` lemmas
* [#5551](https://github.com/leanprover/lean4/pull/5551) upstream `Array.flatten` lemmas
* [#5552](https://github.com/leanprover/lean4/pull/5552) switch obvious cases of array "bang"`[]!` indexing to rely on hypothesis (@TomasPuverle)
* [#5577](https://github.com/leanprover/lean4/pull/5577) add missing simp to `Array.size_feraseIdx`
* [#5586](https://github.com/leanprover/lean4/pull/5586) `Array/Option.unattach`
* `Option`
* [#5272](https://github.com/leanprover/lean4/pull/5272) remove @[simp] from `Option.pmap/pbind` and add simp lemmas
* [#5307](https://github.com/leanprover/lean4/pull/5307) restoring Option simp confluence
* [#5354](https://github.com/leanprover/lean4/pull/5354) remove @[simp] from `Option.bind_map`
* [#5532](https://github.com/leanprover/lean4/pull/5532) `Option.attach`
* [#5539](https://github.com/leanprover/lean4/pull/5539) fix explicitness of `Option.mem_toList`
* `Nat`
* [#5241](https://github.com/leanprover/lean4/pull/5241) add @[simp] to `Nat.add_eq_zero_iff`
* [#5261](https://github.com/leanprover/lean4/pull/5261) Nat bitwise lemmas
* [#5262](https://github.com/leanprover/lean4/pull/5262) `Nat.testBit_add_one` should not be a global simp lemma
* [#5267](https://github.com/leanprover/lean4/pull/5267) protect some Nat bitwise theorems
* [#5305](https://github.com/leanprover/lean4/pull/5305) rename Nat bitwise lemmas
* [#5306](https://github.com/leanprover/lean4/pull/5306) add `Nat.self_sub_mod` lemma
* [#5503](https://github.com/leanprover/lean4/pull/5503) restore @[simp] to upstreamed `Nat.lt_off_iff`
* `Int`
* [#5301](https://github.com/leanprover/lean4/pull/5301) rename `Int.div/mod` to `Int.tdiv/tmod`
* [#5320](https://github.com/leanprover/lean4/pull/5320) add `ediv_nonneg_of_nonpos_of_nonpos` to DivModLemmas (@sakehl)
* `Fin`
* [#5250](https://github.com/leanprover/lean4/pull/5250) missing lemma about `Fin.ofNat'`
* [#5356](https://github.com/leanprover/lean4/pull/5356) `Fin.ofNat'` uses `NeZero`
* [#5379](https://github.com/leanprover/lean4/pull/5379) remove some @[simp]s from Fin lemmas
* [#5380](https://github.com/leanprover/lean4/pull/5380) missing Fin @[simp] lemmas
* `HashMap`
* [#5244](https://github.com/leanprover/lean4/pull/5244) (`DHashMap`|`HashMap`|`HashSet`).(`getKey?`|`getKey`|`getKey!`|`getKeyD`)
* [#5362](https://github.com/leanprover/lean4/pull/5362) remove the last use of `Lean.(HashSet|HashMap)`
* [#5369](https://github.com/leanprover/lean4/pull/5369) `HashSet.ofArray`
* [#5370](https://github.com/leanprover/lean4/pull/5370) `HashSet.partition`
* [#5581](https://github.com/leanprover/lean4/pull/5581) `Singleton`/`Insert`/`Union` instances for `HashMap`/`Set`
* [#5582](https://github.com/leanprover/lean4/pull/5582) `HashSet.all`/`any`
* [#5590](https://github.com/leanprover/lean4/pull/5590) adding `Insert`/`Singleton`/`Union` instances for `HashMap`/`Set.Raw`
* [#5591](https://github.com/leanprover/lean4/pull/5591) `HashSet.Raw.all/any`
* `Monads`
* [#5463](https://github.com/leanprover/lean4/pull/5463) upstream some monad lemmas
* [#5464](https://github.com/leanprover/lean4/pull/5464) adjust simp attributes on monad lemmas
* [#5522](https://github.com/leanprover/lean4/pull/5522) more monadic simp lemmas
* Simp lemma cleanup
* [#5251](https://github.com/leanprover/lean4/pull/5251) remove redundant simp annotations
* [#5253](https://github.com/leanprover/lean4/pull/5253) remove Int simp lemmas that can't fire
* [#5254](https://github.com/leanprover/lean4/pull/5254) variables appearing on both sides of an iff should be implicit
* [#5381](https://github.com/leanprover/lean4/pull/5381) cleaning up redundant simp lemmas
### Compiler, runtime, and FFI
* [#4685](https://github.com/leanprover/lean4/pull/4685) fixes a typo in the C `run_new_frontend` signature
* [#4729](https://github.com/leanprover/lean4/pull/4729) has IR checker suggest using `noncomputable`
* [#5143](https://github.com/leanprover/lean4/pull/5143) adds a shared library for Lake
* [#5437](https://github.com/leanprover/lean4/pull/5437) removes (syntactically) duplicate imports (@euprunin)
* [#5462](https://github.com/leanprover/lean4/pull/5462) updates `src/lake/lakefile.toml` to the adjusted Lake build process
* [#5541](https://github.com/leanprover/lean4/pull/5541) removes new shared libs before build to better support Windows
* [#5558](https://github.com/leanprover/lean4/pull/5558) make `lean.h` compile with MSVC (@kant2002)
* [#5564](https://github.com/leanprover/lean4/pull/5564) removes non-conforming size-0 arrays (@eric-wieser)
### Lake
* Reservoir build cache. Lake will now attempt to fetch a pre-built copy of the package from Reservoir before building it. This is only enabled for packages in the leanprover or leanprover-community organizations on versions indexed by Reservoir. Users can force Lake to build packages from the source by passing --no-cache on the CLI or by setting the LAKE_NO_CACHE environment variable to true. [#5486](https://github.com/leanprover/lean4/pull/5486), [#5572](https://github.com/leanprover/lean4/pull/5572), [#5583](https://github.com/leanprover/lean4/pull/5583), [#5600](https://github.com/leanprover/lean4/pull/5600), [#5641](https://github.com/leanprover/lean4/pull/5641), [#5642](https://github.com/leanprover/lean4/pull/5642).
* [#5504](https://github.com/leanprover/lean4/pull/5504) lake new and lake init now produce TOML configurations by default.
* [#5878](https://github.com/leanprover/lean4/pull/5878) fixes a serious issue where Lake would delete path dependencies when attempting to cleanup a dependency required with an incorrect name.
* **Breaking changes**
* [#5641](https://github.com/leanprover/lean4/pull/5641) A Lake build of target within a package will no longer build a package's dependencies package-level extra target dependencies. At the technical level, a package's extraDep facet no longer transitively builds its dependencies extraDep facets (which include their extraDepTargets).
### Documentation fixes
* [#3918](https://github.com/leanprover/lean4/pull/3918) `@[builtin_doc]` attribute (@digama0)
* [#4305](https://github.com/leanprover/lean4/pull/4305) explains the borrow syntax (@eric-wieser)
* [#5349](https://github.com/leanprover/lean4/pull/5349) adds documentation for `groupBy.loop` (@vihdzp)
* [#5473](https://github.com/leanprover/lean4/pull/5473) fixes typo in `BitVec.mul` docstring (@llllvvuu)
* [#5476](https://github.com/leanprover/lean4/pull/5476) fixes typos in `Lean.MetavarContext`
* [#5481](https://github.com/leanprover/lean4/pull/5481) removes mention of `Lean.withSeconds` (@alexkeizer)
* [#5497](https://github.com/leanprover/lean4/pull/5497) updates documentation and tests for `toUIntX` functions (@TomasPuverle)
* [#5087](https://github.com/leanprover/lean4/pull/5087) mentions that `inferType` does not ensure type correctness
* Many fixes to spelling across the doc-strings, (@euprunin): [#5425](https://github.com/leanprover/lean4/pull/5425) [#5426](https://github.com/leanprover/lean4/pull/5426) [#5427](https://github.com/leanprover/lean4/pull/5427) [#5430](https://github.com/leanprover/lean4/pull/5430) [#5431](https://github.com/leanprover/lean4/pull/5431) [#5434](https://github.com/leanprover/lean4/pull/5434) [#5435](https://github.com/leanprover/lean4/pull/5435) [#5436](https://github.com/leanprover/lean4/pull/5436) [#5438](https://github.com/leanprover/lean4/pull/5438) [#5439](https://github.com/leanprover/lean4/pull/5439) [#5440](https://github.com/leanprover/lean4/pull/5440) [#5599](https://github.com/leanprover/lean4/pull/5599)
### Changes to CI
* [#5343](https://github.com/leanprover/lean4/pull/5343) allows addition of `release-ci` label via comment (@thorimur)
* [#5344](https://github.com/leanprover/lean4/pull/5344) sets check level correctly during workflow (@thorimur)
* [#5444](https://github.com/leanprover/lean4/pull/5444) Mathlib's `lean-pr-testing-NNNN` branches should use Batteries' `lean-pr-testing-NNNN` branches
* [#5489](https://github.com/leanprover/lean4/pull/5489) commit `lake-manifest.json` when updating `lean-pr-testing` branches
* [#5490](https://github.com/leanprover/lean4/pull/5490) use separate secrets for commenting and branching in `pr-release.yml`
v4.12.0
----------
### Language features, tactics, and metaprograms
* `bv_decide` tactic. This release introduces a new tactic for proving goals involving `BitVec` and `Bool`. It reduces the goal to a SAT instance that is refuted by an external solver, and the resulting LRAT proof is checked in Lean. This is used to synthesize a proof of the goal by reflection. As this process uses verified algorithms, proofs generated by this tactic use `Lean.ofReduceBool`, so this tactic includes the Lean compiler as part of the trusted code base. The external solver CaDiCaL is included with Lean and does not need to be installed separately to make use of `bv_decide`.
For example, we can use `bv_decide` to verify that a bit twiddling formula leaves at most one bit set:
```lean
def popcount (x : BitVec 64) : BitVec 64 :=
let rec go (x pop : BitVec 64) : Nat → BitVec 64
| 0 => pop
| n + 1 => go (x >>> 2) (pop + (x &&& 1)) n
go x 0 64
example (x : BitVec 64) : popcount ((x &&& (x - 1)) ^^^ x) ≤ 1 := by
simp only [popcount, popcount.go]
bv_decide
```
When the external solver fails to refute the SAT instance generated by `bv_decide`, it can report a counterexample:
```lean
/--
error: The prover found a counterexample, consider the following assignment:
x = 0xffffffffffffffff#64
-/
#guard_msgs in
example (x : BitVec 64) : x < x + 1 := by
bv_decide
```
See `Lean.Elab.Tactic.BVDecide` for a more detailed overview, and look in `tests/lean/run/bv_*` for examples.
[#5013](https://github.com/leanprover/lean4/pull/5013), [#5074](https://github.com/leanprover/lean4/pull/5074), [#5100](https://github.com/leanprover/lean4/pull/5100), [#5113](https://github.com/leanprover/lean4/pull/5113), [#5137](https://github.com/leanprover/lean4/pull/5137), [#5203](https://github.com/leanprover/lean4/pull/5203), [#5212](https://github.com/leanprover/lean4/pull/5212), [#5220](https://github.com/leanprover/lean4/pull/5220).
* `simp` tactic
* [#4988](https://github.com/leanprover/lean4/pull/4988) fixes a panic in the `reducePow` simproc.
* [#5071](https://github.com/leanprover/lean4/pull/5071) exposes the `index` option to the `dsimp` tactic, introduced to `simp` in [#4202](https://github.com/leanprover/lean4/pull/4202).
* [#5159](https://github.com/leanprover/lean4/pull/5159) fixes a panic at `Fin.isValue` simproc.
* [#5167](https://github.com/leanprover/lean4/pull/5167) and [#5175](https://github.com/leanprover/lean4/pull/5175) rename the `simpCtorEq` simproc to `reduceCtorEq` and makes it optional. (See breaking changes.)
* [#5187](https://github.com/leanprover/lean4/pull/5187) ensures `reduceCtorEq` is enabled in the `norm_cast` tactic.
* [#5073](https://github.com/leanprover/lean4/pull/5073) modifies the simp debug trace messages to tag with "dpre" and "dpost" instead of "pre" and "post" when in definitional rewrite mode. [#5054](https://github.com/leanprover/lean4/pull/5054) explains the `reduce` steps for `trace.Debug.Meta.Tactic.simp` trace messages.
* `ext` tactic
* [#4996](https://github.com/leanprover/lean4/pull/4996) reduces default maximum iteration depth from 1000000 to 100.
* `induction` tactic
* [#5117](https://github.com/leanprover/lean4/pull/5117) fixes a bug where `let` bindings in minor premises wouldn't be counted correctly.
* `omega` tactic
* [#5157](https://github.com/leanprover/lean4/pull/5157) fixes a panic.
* `conv` tactic
* [#5149](https://github.com/leanprover/lean4/pull/5149) improves `arg n` to handle subsingleton instance arguments.
* [#5044](https://github.com/leanprover/lean4/pull/5044) upstreams the `#time` command.
* [#5079](https://github.com/leanprover/lean4/pull/5079) makes `#check` and `#reduce` typecheck the elaborated terms.
* **Incrementality**
* [#4974](https://github.com/leanprover/lean4/pull/4974) fixes regression where we would not interrupt elaboration of previous document versions.
* [#5004](https://github.com/leanprover/lean4/pull/5004) fixes a performance regression.
* [#5001](https://github.com/leanprover/lean4/pull/5001) disables incremental body elaboration in presence of `where` clauses in declarations.
* [#5018](https://github.com/leanprover/lean4/pull/5018) enables infotrees on the command line for ilean generation.
* [#5040](https://github.com/leanprover/lean4/pull/5040) and [#5056](https://github.com/leanprover/lean4/pull/5056) improve performance of info trees.
* [#5090](https://github.com/leanprover/lean4/pull/5090) disables incrementality in the `case .. | ..` tactic.
* [#5312](https://github.com/leanprover/lean4/pull/5312) fixes a bug where changing whitespace after the module header could break subsequent commands.
* **Definitions**
* [#5016](https://github.com/leanprover/lean4/pull/5016) and [#5066](https://github.com/leanprover/lean4/pull/5066) add `clean_wf` tactic to clean up tactic state in `decreasing_by`. This can be disabled with `set_option debug.rawDecreasingByGoal false`.
* [#5055](https://github.com/leanprover/lean4/pull/5055) unifies equational theorems between structural and well-founded recursion.
* [#5041](https://github.com/leanprover/lean4/pull/5041) allows mutually recursive functions to use different parameter names among the “fixed parameter prefix”
* [#4154](https://github.com/leanprover/lean4/pull/4154) and [#5109](https://github.com/leanprover/lean4/pull/5109) add fine-grained equational lemmas for non-recursive functions. See breaking changes.
* [#5129](https://github.com/leanprover/lean4/pull/5129) unifies equation lemmas for recursive and non-recursive definitions. The `backward.eqns.deepRecursiveSplit` option can be set to `false` to get the old behavior. See breaking changes.
* [#5141](https://github.com/leanprover/lean4/pull/5141) adds `f.eq_unfold` lemmas. Now Lean produces the following zoo of rewrite rules:
```
Option.map.eq_1 : Option.map f none = none
Option.map.eq_2 : Option.map f (some x) = some (f x)
Option.map.eq_def : Option.map f p = match o with | none => none | (some x) => some (f x)
Option.map.eq_unfold : Option.map = fun f p => match o with | none => none | (some x) => some (f x)
```
The `f.eq_unfold` variant is especially useful to rewrite with `rw` under binders.
* [#5136](https://github.com/leanprover/lean4/pull/5136) fixes bugs in recursion over predicates.
* **Variable inclusion**
* [#5206](https://github.com/leanprover/lean4/pull/5206) documents that `include` currently only applies to theorems.
* **Elaboration**
* [#4926](https://github.com/leanprover/lean4/pull/4926) fixes a bug where autoparam errors were associated to an incorrect source position.
* [#4833](https://github.com/leanprover/lean4/pull/4833) fixes an issue where cdot anonymous functions (e.g. `(· + ·)`) would not handle ambiguous notation correctly. Numbers the parameters, making this example expand as `fun x1 x2 => x1 + x2` rather than `fun x x_1 => x + x_1`.
* [#5037](https://github.com/leanprover/lean4/pull/5037) improves strength of the tactic that proves array indexing is in bounds.
* [#5119](https://github.com/leanprover/lean4/pull/5119) fixes a bug in the tactic that proves indexing is in bounds where it could loop in the presence of mvars.
* [#5072](https://github.com/leanprover/lean4/pull/5072) makes the structure type clickable in "not a field of structure" errors for structure instance notation.
* [#4717](https://github.com/leanprover/lean4/pull/4717) fixes a bug where mutual `inductive` commands could create terms that the kernel rejects.
* [#5142](https://github.com/leanprover/lean4/pull/5142) fixes a bug where `variable` could fail when mixing binder updates and declarations.
* **Other fixes or improvements**
* [#5118](https://github.com/leanprover/lean4/pull/5118) changes the definition of the `syntheticHole` parser so that hovering over `_` in `?_` gives the docstring for synthetic holes.
* [#5173](https://github.com/leanprover/lean4/pull/5173) uses the emoji variant selector for ✅️,❌️,💥️ in messages, improving fonts selection.
* [#5183](https://github.com/leanprover/lean4/pull/5183) fixes a bug in `rename_i` where implementation detail hypotheses could be renamed.
### Language server, widgets, and IDE extensions
* [#4821](https://github.com/leanprover/lean4/pull/4821) resolves two language server bugs that especially affect Windows users. (1) Editing the header could result in the watchdog not correctly restarting the file worker, which would lead to the file seemingly being processed forever. (2) On an especially slow Windows machine, we found that starting the language server would sometimes not succeed at all. This PR also resolves an issue where we would not correctly emit messages that we received while the file worker is being restarted to the corresponding file worker after the restart.
* [#5006](https://github.com/leanprover/lean4/pull/5006) updates the user widget manual.
* [#5193](https://github.com/leanprover/lean4/pull/5193) updates the quickstart guide with the new display name for the Lean 4 extension ("Lean 4").
* [#5185](https://github.com/leanprover/lean4/pull/5185) fixes a bug where over time "import out of date" messages would accumulate.
* [#4900](https://github.com/leanprover/lean4/pull/4900) improves ilean loading performance by about a factor of two. Optimizes the JSON parser and the conversion from JSON to Lean data structures; see PR description for details.
* **Other fixes or improvements**
* [#5031](https://github.com/leanprover/lean4/pull/5031) localizes an instance in `Lsp.Diagnostics`.
### Pretty printing
* [#4976](https://github.com/leanprover/lean4/pull/4976) introduces `@[app_delab]`, a macro for creating delaborators for particular constants. The `@[app_delab ident]` syntax resolves `ident` to its constant name `name` and then expands to `@[delab app.name]`.
* [#4982](https://github.com/leanprover/lean4/pull/4982) fixes a bug where the pretty printer assumed structure projections were type correct (such terms can appear in type mismatch errors). Improves hoverability of `#print` output for structures.
* [#5218](https://github.com/leanprover/lean4/pull/5218) and [#5239](https://github.com/leanprover/lean4/pull/5239) add `pp.exprSizes` debugging option. When true, each pretty printed expression is prefixed with `[size a/b/c]`, where `a` is the size without sharing, `b` is the actual size, and `c` is the size with the maximum possible sharing.
### Library
* [#5020](https://github.com/leanprover/lean4/pull/5020) swaps the parameters to `Membership.mem`. A purpose of this change is to make set-like `CoeSort` coercions to refer to the eta-expanded function `fun x => Membership.mem s x`, which can reduce in many computations. Another is that having the `s` argument first leads to better discrimination tree keys. (See breaking changes.)
* `Array`
* [#4970](https://github.com/leanprover/lean4/pull/4970) adds `@[ext]` attribute to `Array.ext`.
* [#4957](https://github.com/leanprover/lean4/pull/4957) deprecates `Array.get_modify`.
* `List`
* [#4995](https://github.com/leanprover/lean4/pull/4995) upstreams `List.findIdx` lemmas.
* [#5029](https://github.com/leanprover/lean4/pull/5029), [#5048](https://github.com/leanprover/lean4/pull/5048) and [#5132](https://github.com/leanprover/lean4/pull/5132) add `List.Sublist` lemmas, some upstreamed. [#5077](https://github.com/leanprover/lean4/pull/5077) fixes implicitness in refl/rfl lemma binders. add `List.Sublist` theorems.
* [#5047](https://github.com/leanprover/lean4/pull/5047) upstreams `List.Pairwise` lemmas.
* [#5053](https://github.com/leanprover/lean4/pull/5053), [#5124](https://github.com/leanprover/lean4/pull/5124), and [#5161](https://github.com/leanprover/lean4/pull/5161) add `List.find?/findSome?/findIdx?` theorems.
* [#5039](https://github.com/leanprover/lean4/pull/5039) adds `List.foldlRecOn` and `List.foldrRecOn` recursion principles to prove things about `List.foldl` and `List.foldr`.
* [#5069](https://github.com/leanprover/lean4/pull/5069) upstreams `List.Perm`.
* [#5092](https://github.com/leanprover/lean4/pull/5092) and [#5107](https://github.com/leanprover/lean4/pull/5107) add `List.mergeSort` and a fast `@[csimp]` implementation.
* [#5103](https://github.com/leanprover/lean4/pull/5103) makes the simp lemmas for `List.subset` more aggressive.
* [#5106](https://github.com/leanprover/lean4/pull/5106) changes the statement of `List.getLast?_cons`.
* [#5123](https://github.com/leanprover/lean4/pull/5123) and [#5158](https://github.com/leanprover/lean4/pull/5158) add `List.range` and `List.iota` lemmas.
* [#5130](https://github.com/leanprover/lean4/pull/5130) adds `List.join` lemmas.
* [#5131](https://github.com/leanprover/lean4/pull/5131) adds `List.append` lemmas.
* [#5152](https://github.com/leanprover/lean4/pull/5152) adds `List.erase(|P|Idx)` lemmas.
* [#5127](https://github.com/leanprover/lean4/pull/5127) makes miscellaneous lemma updates.
* [#5153](https://github.com/leanprover/lean4/pull/5153) and [#5160](https://github.com/leanprover/lean4/pull/5160) add lemmas about `List.attach` and `List.pmap`.
* [#5164](https://github.com/leanprover/lean4/pull/5164), [#5177](https://github.com/leanprover/lean4/pull/5177), and [#5215](https://github.com/leanprover/lean4/pull/5215) add `List.find?` and `List.range'/range/iota` lemmas.
* [#5196](https://github.com/leanprover/lean4/pull/5196) adds `List.Pairwise_erase` and related lemmas.
* [#5151](https://github.com/leanprover/lean4/pull/5151) and [#5163](https://github.com/leanprover/lean4/pull/5163) improve confluence of `List` simp lemmas. [#5105](https://github.com/leanprover/lean4/pull/5105) and [#5102](https://github.com/leanprover/lean4/pull/5102) adjust `List` simp lemmas.
* [#5178](https://github.com/leanprover/lean4/pull/5178) removes `List.getLast_eq_iff_getLast_eq_some` as a simp lemma.
* [#5210](https://github.com/leanprover/lean4/pull/5210) reverses the meaning of `List.getElem_drop` and `List.getElem_drop'`.
* [#5214](https://github.com/leanprover/lean4/pull/5214) moves `@[csimp]` lemmas earlier where possible.
* `Nat` and `Int`
* [#5104](https://github.com/leanprover/lean4/pull/5104) adds `Nat.add_left_eq_self` and relatives.
* [#5146](https://github.com/leanprover/lean4/pull/5146) adds missing `Nat.and_xor_distrib_(left|right)`.
* [#5148](https://github.com/leanprover/lean4/pull/5148) and [#5190](https://github.com/leanprover/lean4/pull/5190) improve `Nat` and `Int` simp lemma confluence.
* [#5165](https://github.com/leanprover/lean4/pull/5165) adjusts `Int` simp lemmas.
* [#5166](https://github.com/leanprover/lean4/pull/5166) adds `Int` lemmas relating `neg` and `emod`/`mod`.
* [#5208](https://github.com/leanprover/lean4/pull/5208) reverses the direction of the `Int.toNat_sub` simp lemma.
* [#5209](https://github.com/leanprover/lean4/pull/5209) adds `Nat.bitwise` lemmas.
* [#5230](https://github.com/leanprover/lean4/pull/5230) corrects the docstrings for integer division and modulus.
* `Option`
* [#5128](https://github.com/leanprover/lean4/pull/5128) and [#5154](https://github.com/leanprover/lean4/pull/5154) add `Option` lemmas.
* `BitVec`
* [#4889](https://github.com/leanprover/lean4/pull/4889) adds `sshiftRight` bitblasting.
* [#4981](https://github.com/leanprover/lean4/pull/4981) adds `Std.Associative` and `Std.Commutative` instances for `BitVec.[and|or|xor]`.
* [#4913](https://github.com/leanprover/lean4/pull/4913) enables `missingDocs` error for `BitVec` modules.
* [#4930](https://github.com/leanprover/lean4/pull/4930) makes parameter names for `BitVec` more consistent.
* [#5098](https://github.com/leanprover/lean4/pull/5098) adds `BitVec.intMin`. Introduces `boolToPropSimps` simp set for converting from boolean to propositional expressions.
* [#5200](https://github.com/leanprover/lean4/pull/5200) and [#5217](https://github.com/leanprover/lean4/pull/5217) rename `BitVec.getLsb` to `BitVec.getLsbD`, etc., to bring naming in line with `List`/`Array`/etc.
* **Theorems:** [#4977](https://github.com/leanprover/lean4/pull/4977), [#4951](https://github.com/leanprover/lean4/pull/4951), [#4667](https://github.com/leanprover/lean4/pull/4667), [#5007](https://github.com/leanprover/lean4/pull/5007), [#4997](https://github.com/leanprover/lean4/pull/4997), [#5083](https://github.com/leanprover/lean4/pull/5083), [#5081](https://github.com/leanprover/lean4/pull/5081), [#4392](https://github.com/leanprover/lean4/pull/4392)
* `UInt`
* [#4514](https://github.com/leanprover/lean4/pull/4514) fixes naming convention for `UInt` lemmas.
* `Std.HashMap` and `Std.HashSet`
* [#4943](https://github.com/leanprover/lean4/pull/4943) deprecates variants of hash map query methods. (See breaking changes.)
* [#4917](https://github.com/leanprover/lean4/pull/4917) switches the library and Lean to `Std.HashMap` and `Std.HashSet` almost everywhere.
* [#4954](https://github.com/leanprover/lean4/pull/4954) deprecates `Lean.HashMap` and `Lean.HashSet`.
* [#5023](https://github.com/leanprover/lean4/pull/5023) cleans up lemma parameters.
* `Std.Sat` (for `bv_decide`)
* [#4933](https://github.com/leanprover/lean4/pull/4933) adds definitions of SAT and CNF.
* [#4953](https://github.com/leanprover/lean4/pull/4953) defines "and-inverter graphs" (AIGs) as described in section 3 of [Davis-Swords 2013](https://arxiv.org/pdf/1304.7861.pdf).
* **Parsec**
* [#4774](https://github.com/leanprover/lean4/pull/4774) generalizes the `Parsec` library, allowing parsing of iterable data beyond `String` such as `ByteArray`. (See breaking changes.)
* [#5115](https://github.com/leanprover/lean4/pull/5115) moves `Lean.Data.Parsec` to `Std.Internal.Parsec` for bootstrappng reasons.
* `Thunk`
* [#4969](https://github.com/leanprover/lean4/pull/4969) upstreams `Thunk.ext`.
* **IO**
* [#4973](https://github.com/leanprover/lean4/pull/4973) modifies `IO.FS.lines` to handle `\r\n` on all operating systems instead of just on Windows.
* [#5125](https://github.com/leanprover/lean4/pull/5125) adds `createTempFile` and `withTempFile` for creating temporary files that can only be read and written by the current user.
* **Other fixes or improvements**
* [#4945](https://github.com/leanprover/lean4/pull/4945) adds `Array`, `Bool` and `Prod` utilities from LeanSAT.
* [#4960](https://github.com/leanprover/lean4/pull/4960) adds `Relation.TransGen.trans`.
* [#5012](https://github.com/leanprover/lean4/pull/5012) states `WellFoundedRelation Nat` using `<`, not `Nat.lt`.
* [#5011](https://github.com/leanprover/lean4/pull/5011) uses `` instead of `Not (Eq ...)` in `Fin.ne_of_val_ne`.
* [#5197](https://github.com/leanprover/lean4/pull/5197) upstreams `Fin.le_antisymm`.
* [#5042](https://github.com/leanprover/lean4/pull/5042) reduces usage of `refine'`.
* [#5101](https://github.com/leanprover/lean4/pull/5101) adds about `if-then-else` and `Option`.
* [#5112](https://github.com/leanprover/lean4/pull/5112) adds basic instances for `ULift` and `PLift`.
* [#5133](https://github.com/leanprover/lean4/pull/5133) and [#5168](https://github.com/leanprover/lean4/pull/5168) make fixes from running the simpNF linter over Lean.
* [#5156](https://github.com/leanprover/lean4/pull/5156) removes a bad simp lemma in `omega` theory.
* [#5155](https://github.com/leanprover/lean4/pull/5155) improves confluence of `Bool` simp lemmas.
* [#5162](https://github.com/leanprover/lean4/pull/5162) improves confluence of `Function.comp` simp lemmas.
* [#5191](https://github.com/leanprover/lean4/pull/5191) improves confluence of `if-then-else` simp lemmas.
* [#5147](https://github.com/leanprover/lean4/pull/5147) adds `@[elab_as_elim]` to `Quot.rec`, `Nat.strongInductionOn` and `Nat.casesStrongInductionOn`, and also renames the latter two to `Nat.strongRecOn` and `Nat.casesStrongRecOn` (deprecated in [#5179](https://github.com/leanprover/lean4/pull/5179)).
* [#5180](https://github.com/leanprover/lean4/pull/5180) disables some simp lemmas with bad discrimination tree keys.
* [#5189](https://github.com/leanprover/lean4/pull/5189) cleans up internal simp lemmas that had leaked.
* [#5198](https://github.com/leanprover/lean4/pull/5198) cleans up `allowUnsafeReducibility`.
* [#5229](https://github.com/leanprover/lean4/pull/5229) removes unused lemmas from some `simp` tactics.
* [#5199](https://github.com/leanprover/lean4/pull/5199) removes >6 month deprecations.
### Lean internals
* **Performance**
* Some core algorithms have been rewritten in C++ for performance.
* [#4910](https://github.com/leanprover/lean4/pull/4910) and [#4912](https://github.com/leanprover/lean4/pull/4912) reimplement `instantiateLevelMVars`.
* [#4915](https://github.com/leanprover/lean4/pull/4915), [#4922](https://github.com/leanprover/lean4/pull/4922), and [#4931](https://github.com/leanprover/lean4/pull/4931) reimplement `instantiateExprMVars`, 30% faster on a benchmark.
* [#4934](https://github.com/leanprover/lean4/pull/4934) has optimizations for the kernel's `Expr` equality test.
* [#4990](https://github.com/leanprover/lean4/pull/4990) fixes bug in hashing for the kernel's `Expr` equality test.
* [#4935](https://github.com/leanprover/lean4/pull/4935) and [#4936](https://github.com/leanprover/lean4/pull/4936) skip some `PreDefinition` transformations if they are not needed.
* [#5225](https://github.com/leanprover/lean4/pull/5225) adds caching for visited exprs at `CheckAssignmentQuick` in `ExprDefEq`.
* [#5226](https://github.com/leanprover/lean4/pull/5226) maximizes term sharing at `instantiateMVarDeclMVars`, used by `runTactic`.
* **Diagnostics and profiling**
* [#4923](https://github.com/leanprover/lean4/pull/4923) adds profiling for `instantiateMVars` in `Lean.Elab.MutualDef`, which can be a bottleneck there.
* [#4924](https://github.com/leanprover/lean4/pull/4924) adds diagnostics for large theorems, controlled by the `diagnostics.threshold.proofSize` option.
* [#4897](https://github.com/leanprover/lean4/pull/4897) improves display of diagnostic results.
* **Other fixes or improvements**
* [#4921](https://github.com/leanprover/lean4/pull/4921) cleans up `Expr.betaRev`.
* [#4940](https://github.com/leanprover/lean4/pull/4940) fixes tests by not writing directly to stdout, which is unreliable now that elaboration and reporting are executed in separate threads.
* [#4955](https://github.com/leanprover/lean4/pull/4955) documents that `stderrAsMessages` is now the default on the command line as well.
* [#4647](https://github.com/leanprover/lean4/pull/4647) adjusts documentation for building on macOS.
* [#4987](https://github.com/leanprover/lean4/pull/4987) makes regular mvar assignments take precedence over delayed ones in `instantiateMVars`. Normally delayed assignment metavariables are never directly assigned, but on errors Lean assigns `sorry` to unassigned metavariables.
* [#4967](https://github.com/leanprover/lean4/pull/4967) adds linter name to errors when a linter crashes.
* [#5043](https://github.com/leanprover/lean4/pull/5043) cleans up command line snapshots logic.
* [#5067](https://github.com/leanprover/lean4/pull/5067) minimizes some imports.
* [#5068](https://github.com/leanprover/lean4/pull/5068) generalizes the monad for `addMatcherInfo`.
* [f71a1f](https://github.com/leanprover/lean4/commit/f71a1fb4ae958fccb3ad4d48786a8f47ced05c15) adds missing test for [#5126](https://github.com/leanprover/lean4/issues/5126).
* [#5201](https://github.com/leanprover/lean4/pull/5201) restores a test.
* [#3698](https://github.com/leanprover/lean4/pull/3698) fixes a bug where label attributes did not pass on the attribute kind.
* Typos: [#5080](https://github.com/leanprover/lean4/pull/5080), [#5150](https://github.com/leanprover/lean4/pull/5150), [#5202](https://github.com/leanprover/lean4/pull/5202)
### Compiler, runtime, and FFI
* [#3106](https://github.com/leanprover/lean4/pull/3106) moves frontend to new snapshot architecture. Note that `Frontend.processCommand` and `FrontendM` are no longer used by Lean core, but they will be preserved.
* [#4919](https://github.com/leanprover/lean4/pull/4919) adds missing include in runtime for `AUTO_THREAD_FINALIZATION` feature on Windows.
* [#4941](https://github.com/leanprover/lean4/pull/4941) adds more `LEAN_EXPORT`s for Windows.
* [#4911](https://github.com/leanprover/lean4/pull/4911) improves formatting of CLI help text for the frontend.
* [#4950](https://github.com/leanprover/lean4/pull/4950) improves file reading and writing.
* `readBinFile` and `readFile` now only require two system calls (`stat` + `read`) instead of one `read` per 1024 byte chunk.
* `Handle.getLine` and `Handle.putStr` no longer get tripped up by NUL characters.
* [#4971](https://github.com/leanprover/lean4/pull/4971) handles the SIGBUS signal when detecting stack overflows.
* [#5062](https://github.com/leanprover/lean4/pull/5062) avoids overwriting existing signal handlers, like in [rust-lang/rust#69685](https://github.com/rust-lang/rust/pull/69685).
* [#4860](https://github.com/leanprover/lean4/pull/4860) improves workarounds for building on Windows. Splits `libleanshared` on Windows to avoid symbol limit, removes the `LEAN_EXPORT` denylist workaround, adds missing `LEAN_EXPORT`s.
* [#4952](https://github.com/leanprover/lean4/pull/4952) output panics into Lean's redirected stderr, ensuring panics ARE visible as regular messages in the language server and properly ordered in relation to other messages on the command line.
* [#4963](https://github.com/leanprover/lean4/pull/4963) links LibUV.
### Lake
* [#5030](https://github.com/leanprover/lean4/pull/5030) removes dead code.
* [#4770](https://github.com/leanprover/lean4/pull/4770) adds additional fields to the package configuration which will be used by Reservoir. See the PR description for details.
### DevOps/CI
* [#4914](https://github.com/leanprover/lean4/pull/4914) and [#4937](https://github.com/leanprover/lean4/pull/4937) improve the release checklist.
* [#4925](https://github.com/leanprover/lean4/pull/4925) ignores stale leanpkg tests.
* [#5003](https://github.com/leanprover/lean4/pull/5003) upgrades `actions/cache` in CI.
* [#5010](https://github.com/leanprover/lean4/pull/5010) sets `save-always` in cache actions in CI.
* [#5008](https://github.com/leanprover/lean4/pull/5008) adds more libuv search patterns for the speedcenter.
* [#5009](https://github.com/leanprover/lean4/pull/5009) reduce number of runs in the speedcenter for "fast" benchmarks from 10 to 3.
* [#5014](https://github.com/leanprover/lean4/pull/5014) adjusts lakefile editing to use new `git` syntax in `pr-release` workflow.
* [#5025](https://github.com/leanprover/lean4/pull/5025) has `pr-release` workflow pass `--retry` to `curl`.
* [#5022](https://github.com/leanprover/lean4/pull/5022) builds MacOS Aarch64 release for PRs by default.
* [#5045](https://github.com/leanprover/lean4/pull/5045) adds libuv to the required packages heading in macos docs.
* [#5034](https://github.com/leanprover/lean4/pull/5034) fixes the install name of `libleanshared_1` on macOS.
* [#5051](https://github.com/leanprover/lean4/pull/5051) fixes Windows stage 0.
* [#5052](https://github.com/leanprover/lean4/pull/5052) fixes 32bit stage 0 builds in CI.
* [#5057](https://github.com/leanprover/lean4/pull/5057) avoids rebuilding `leanmanifest` in each build.
* [#5099](https://github.com/leanprover/lean4/pull/5099) makes `restart-on-label` workflow also filter by commit SHA.
* [#4325](https://github.com/leanprover/lean4/pull/4325) adds CaDiCaL.
### Breaking changes
* [LibUV](https://libuv.org/) is now required to build Lean. This change only affects developers who compile Lean themselves instead of obtaining toolchains via `elan`. We have updated the official build instructions with information on how to obtain LibUV on our supported platforms. ([#4963](https://github.com/leanprover/lean4/pull/4963))
* Recursive definitions with a `decreasing_by` clause that begins with `simp_wf` may break. Try removing `simp_wf` or replacing it with `simp`. ([#5016](https://github.com/leanprover/lean4/pull/5016))
* The behavior of `rw [f]` where `f` is a non-recursive function defined by pattern matching changed.
For example, preciously, `rw [Option.map]` would rewrite `Option.map f o` to `match o with … `. Now this rewrite fails because it will use the equational lemmas, and these require constructors just like for `List.map`.
Remedies:
* Split on `o` before rewriting.
* Use `rw [Option.map.eq_def]`, which rewrites any (saturated) application of `Option.map`.
* Use `set_option backward.eqns.nonrecursive false` when *defining* the function in question.
([#4154](https://github.com/leanprover/lean4/pull/4154))
* The unified handling of equation lemmas for recursive and non-recursive functions can break existing code, as there now can be extra equational lemmas:
* Explicit uses of `f.eq_2` might have to be adjusted if the numbering changed.
* Uses of `rw [f]` or `simp [f]` may no longer apply if they previously matched (and introduced a `match` statement), when the equational lemmas got more fine-grained.
In this case either case analysis on the parameters before rewriting helps, or setting the option `backward.eqns.deepRecursiveSplit false` while *defining* the function.
([#5129](https://github.com/leanprover/lean4/pull/5129), [#5207](https://github.com/leanprover/lean4/pull/5207))
* The `reduceCtorEq` simproc is now optional, and it might need to be included in lists of simp lemmas, like `simp only [reduceCtorEq]`. This simproc is responsible for reducing equalities of constructors. ([#5167](https://github.com/leanprover/lean4/pull/5167))
* `Nat.strongInductionOn` is now `Nat.strongRecOn` and `Nat.caseStrongInductionOn` to `Nat.caseStrongRecOn`. ([#5147](https://github.com/leanprover/lean4/pull/5147))
* The parameters to `Membership.mem` have been swapped, which affects all `Membership` instances. ([#5020](https://github.com/leanprover/lean4/pull/5020))
* The meanings of `List.getElem_drop` and `List.getElem_drop'` have been reversed and the first is now a simp lemma. ([#5210](https://github.com/leanprover/lean4/pull/5210))
* The `Parsec` library has moved from `Lean.Data.Parsec` to `Std.Internal.Parsec`. The `Parsec` type is now more general with a parameter for an iterable. Users parsing strings can migrate to `Parser` in the `Std.Internal.Parsec.String` namespace, which also includes string-focused parsing combinators. ([#4774](https://github.com/leanprover/lean4/pull/4774))
* The `Lean` module has switched from `Lean.HashMap` and `Lean.HashSet` to `Std.HashMap` and `Std.HashSet` ([#4943](https://github.com/leanprover/lean4/pull/4943)). `Lean.HashMap` and `Lean.HashSet` are now deprecated ([#4954](https://github.com/leanprover/lean4/pull/4954)) and will be removed in a future release. Users of `Lean` APIs that interact with hash maps, for example `Lean.Environment.const2ModIdx`, might encounter minor breakage due to the following changes from `Lean.HashMap` to `Std.HashMap`:
* query functions use the term `get` instead of `find`, ([#4943](https://github.com/leanprover/lean4/pull/4943))
* the notation `map[key]` no longer returns an optional value but instead expects a proof that the key is present in the map. The previous behavior is available via the `map[key]?` notation.
Development in progress.
v4.11.0
----------
@@ -654,7 +21,7 @@ v4.11.0
See breaking changes below.
PRs: [#4883](https://github.com/leanprover/lean4/pull/4883), [#4814](https://github.com/leanprover/lean4/pull/4814), [#5000](https://github.com/leanprover/lean4/pull/5000), [#5036](https://github.com/leanprover/lean4/pull/5036), [#5138](https://github.com/leanprover/lean4/pull/5138), [0edf1b](https://github.com/leanprover/lean4/commit/0edf1bac392f7e2fe0266b28b51c498306363a84).
PRs: [#4883](https://github.com/leanprover/lean4/pull/4883), [1242ff](https://github.com/leanprover/lean4/commit/1242ffbfb5a79296041683682268e770fc3cf820), [#5000](https://github.com/leanprover/lean4/pull/5000), [#5036](https://github.com/leanprover/lean4/pull/5036), [#5138](https://github.com/leanprover/lean4/pull/5138), [0edf1b](https://github.com/leanprover/lean4/commit/0edf1bac392f7e2fe0266b28b51c498306363a84).
* **Recursive definitions**
* Structural recursion can now be explicitly requested using

View File

@@ -15,24 +15,17 @@ Mode](https://docs.microsoft.com/en-us/windows/apps/get-started/enable-your-devi
which will allow Lean to create symlinks that e.g. enable go-to-definition in
the stdlib.
## Installing the Windows SDK
Install the Windows SDK from [Microsoft](https://developer.microsoft.com/en-us/windows/downloads/windows-sdk/).
The oldest supported version is 10.0.18362.0. If you installed the Windows SDK to the default location,
then there should be a directory with the version number at `C:\Program Files (x86)\Windows Kits\10\Include`.
If there are multiple directories, only the highest version number matters.
## Installing dependencies
[The official webpage of MSYS2][msys2] provides one-click installers.
Once installed, you should run the "MSYS2 CLANG64" shell from the start menu (the one that runs `clang64.exe`).
Do not run "MSYS2 MSYS" or "MSYS2 MINGW64" instead!
MSYS2 has a package management system, [pacman][pacman].
Once installed, you should run the "MSYS2 MinGW 64-bit shell" from the start menu (the one that runs `mingw64.exe`).
Do not run "MSYS2 MSYS" instead!
MSYS2 has a package management system, [pacman][pacman], which is used in Arch Linux.
Here are the commands to install all dependencies needed to compile Lean on your machine.
```bash
pacman -S make python mingw-w64-clang-x86_64-cmake mingw-w64-clang-x86_64-clang mingw-w64-clang-x86_64-ccache mingw-w64-clang-x86_64-libuv mingw-w64-clang-x86_64-gmp git unzip diffutils binutils
pacman -S make python mingw-w64-x86_64-cmake mingw-w64-x86_64-clang mingw-w64-x86_64-ccache mingw-w64-x86_64-libuv mingw-w64-x86_64-gmp git unzip diffutils binutils
```
You should now be able to run these commands:
@@ -68,7 +61,8 @@ If you want a version that can run independently of your MSYS install
then you need to copy the following dependent DLL's from where ever
they are installed in your MSYS setup:
- libc++.dll
- libgcc_s_seh-1.dll
- libstdc++-6.dll
- libgmp-10.dll
- libuv-1.dll
- libwinpthread-1.dll
@@ -88,6 +82,6 @@ version clang to your path.
**-bash: gcc: command not found**
Make sure `/clang64/bin` is in your PATH environment. If it is not then
check you launched the MSYS2 CLANG64 shell from the start menu.
(The one that runs `clang64.exe`).
Make sure `/mingw64/bin` is in your PATH environment. If it is not then
check you launched the MSYS2 MinGW 64-bit shell from the start menu.
(The one that runs `mingw64.exe`).

View File

@@ -138,8 +138,8 @@ definition:
-/
instance : Applicative List where
pure := List.singleton
seq f x := List.flatMap f fun y => Functor.map y (x ())
pure := List.pure
seq f x := List.bind f fun y => Functor.map y (x ())
/-!
Notice you can now sequence a _list_ of functions and a _list_ of items.

View File

@@ -128,8 +128,8 @@ Applying the identity function through an applicative structure should not chang
values or structure. For example:
-/
instance : Applicative List where
pure := List.singleton
seq f x := List.flatMap f fun y => Functor.map y (x ())
pure := List.pure
seq f x := List.bind f fun y => Functor.map y (x ())
#eval pure id <*> [1, 2, 3] -- [1, 2, 3]
/-!
@@ -235,8 +235,8 @@ structure or its values.
Left identity is `x >>= pure = x` and is demonstrated by the following examples on a monadic `List`:
-/
instance : Monad List where
pure := List.singleton
bind := List.flatMap
pure := List.pure
bind := List.bind
def a := ["apple", "orange"]

View File

@@ -192,8 +192,8 @@ implementation of `pure` and `bind`.
-/
instance : Monad List where
pure := List.singleton
bind := List.flatMap
pure := List.pure
bind := List.bind
/-!
Like you saw with the applicative `seq` operator, the `bind` operator applies the given function

View File

@@ -7,7 +7,7 @@ Platforms built & tested by our CI, available as binary releases via elan (see b
* x86-64 Linux with glibc 2.27+
* x86-64 macOS 10.15+
* aarch64 (Apple Silicon) macOS 10.15+
* x86-64 Windows 11 (any version), Windows 10 (version 1903 or higher), Windows Server 2022
* x86-64 Windows 10+
### Tier 2

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@@ -38,24 +38,8 @@
# more convenient `ctest` output
CTEST_OUTPUT_ON_FAILURE = 1;
} // pkgs.lib.optionalAttrs pkgs.stdenv.isLinux {
GMP = (pkgsDist.gmp.override { withStatic = true; }).overrideAttrs (attrs:
pkgs.lib.optionalAttrs (pkgs.stdenv.system == "aarch64-linux") {
# would need additional linking setup on Linux aarch64, we don't use it anywhere else either
hardeningDisable = [ "stackprotector" ];
});
LIBUV = pkgsDist.libuv.overrideAttrs (attrs: {
configureFlags = ["--enable-static"];
hardeningDisable = [ "stackprotector" ];
# Sync version with CMakeLists.txt
version = "1.48.0";
src = pkgs.fetchFromGitHub {
owner = "libuv";
repo = "libuv";
rev = "v1.48.0";
sha256 = "100nj16fg8922qg4m2hdjh62zv4p32wyrllsvqr659hdhjc03bsk";
};
doCheck = false;
});
GMP = pkgsDist.gmp.override { withStatic = true; };
LIBUV = pkgsDist.libuv.overrideAttrs (attrs: { configureFlags = ["--enable-static"]; });
GLIBC = pkgsDist.glibc;
GLIBC_DEV = pkgsDist.glibc.dev;
GCC_LIB = pkgsDist.gcc.cc.lib;

View File

@@ -0,0 +1,3 @@
* The `Lean` module has switched from `Lean.HashMap` and `Lean.HashSet` to `Std.HashMap` and `Std.HashSet`. `Lean.HashMap` and `Lean.HashSet` are now deprecated and will be removed in a future release. Users of `Lean` APIs that interact with hash maps, for example `Lean.Environment.const2ModIdx`, might encounter minor breakage due to the following breaking changes from `Lean.HashMap` to `Std.HashMap`:
* query functions use the term `get` instead of `find`,
* the notation `map[key]` no longer returns an optional value but expects a proof that the key is present in the map instead. The previous behavior is available via the `map[key]?` notation.

1
releases_drafts/libuv.md Normal file
View File

@@ -0,0 +1 @@
* #4963 [LibUV](https://libuv.org/) is now required to build Lean. This change only affects developers who compile Lean themselves instead of obtaining toolchains via `elan`. We have updated the official build instructions with information on how to obtain LibUV on our supported platforms.

View File

@@ -48,8 +48,6 @@ $CP llvm-host/lib/*/lib{c++,c++abi,unwind}.* llvm-host/lib/
$CP -r llvm/include/*-*-* llvm-host/include/
# glibc: use for linking (so Lean programs don't embed newer symbol versions), but not for running (because libc.so, librt.so, and ld.so must be compatible)!
$CP $GLIBC/lib/libc_nonshared.a stage1/lib/glibc
# libpthread_nonshared.a must be linked in order to be able to use `pthread_atfork(3)`. LibUV uses this function.
$CP $GLIBC/lib/libpthread_nonshared.a stage1/lib/glibc
for f in $GLIBC/lib/lib{c,dl,m,rt,pthread}-*; do b=$(basename $f); cp $f stage1/lib/glibc/${b%-*}.so; done
OPTIONS=()
echo -n " -DLEAN_STANDALONE=ON"
@@ -64,8 +62,8 @@ fi
# use `-nostdinc` to make sure headers are not visible by default (in particular, not to `#include_next` in the clang headers),
# but do not change sysroot so users can still link against system libs
echo -n " -DLEANC_INTERNAL_FLAGS='-nostdinc -isystem ROOT/include/clang' -DLEANC_CC=ROOT/bin/clang"
echo -n " -DLEANC_INTERNAL_LINKER_FLAGS='-L ROOT/lib -L ROOT/lib/glibc ROOT/lib/glibc/libc_nonshared.a ROOT/lib/glibc/libpthread_nonshared.a -Wl,--as-needed -Wl,-Bstatic -lgmp -lunwind -luv -lpthread -ldl -lrt -Wl,-Bdynamic -Wl,--no-as-needed -fuse-ld=lld'"
echo -n " -DLEANC_INTERNAL_LINKER_FLAGS='-L ROOT/lib -L ROOT/lib/glibc ROOT/lib/glibc/libc_nonshared.a -Wl,--as-needed -Wl,-Bstatic -lgmp -lunwind -luv -Wl,-Bdynamic -Wl,--no-as-needed -fuse-ld=lld'"
# when not using the above flags, link GMP dynamically/as usual
echo -n " -DLEAN_EXTRA_LINKER_FLAGS='-Wl,--as-needed -lgmp -luv -lpthread -ldl -lrt -Wl,--no-as-needed'"
echo -n " -DLEAN_EXTRA_LINKER_FLAGS='-Wl,--as-needed -lgmp -luv -Wl,--no-as-needed'"
# do not set `LEAN_CC` for tests
echo -n " -DLEAN_TEST_VARS=''"

View File

@@ -31,21 +31,15 @@ cp /clang64/lib/{crtbegin,crtend,crt2,dllcrt2}.o stage1/lib/
# runtime
(cd llvm; cp --parents lib/clang/*/lib/*/libclang_rt.builtins* ../stage1)
# further dependencies
# Note: even though we're linking against libraries like `libbcrypt.a` which appear to be static libraries from the file name,
# we're not actually linking statically against the code.
# Rather, `libbcrypt.a` is an import library (see https://en.wikipedia.org/wiki/Dynamic-link_library#Import_libraries) that just
# tells the compiler how to dynamically link against `bcrypt.dll` (which is located in the System32 folder).
# This distinction is relevant specifically for `libicu.a`/`icu.dll` because there we want updates to the time zone database to
# be delivered to users via Windows Update without having to recompile Lean or Lean programs.
cp /clang64/lib/lib{m,bcrypt,mingw32,moldname,mingwex,msvcrt,pthread,advapi32,shell32,user32,kernel32,ucrtbase,psapi,iphlpapi,userenv,ws2_32,dbghelp,ole32,icu}.* /clang64/lib/libgmp.a /clang64/lib/libuv.a llvm/lib/lib{c++,c++abi,unwind}.a stage1/lib/
cp /clang64/lib/lib{m,bcrypt,mingw32,moldname,mingwex,msvcrt,pthread,advapi32,shell32,user32,kernel32,ucrtbase}.* /clang64/lib/libgmp.a /clang64/lib/libuv.a llvm/lib/lib{c++,c++abi,unwind}.a stage1/lib/
echo -n " -DLEAN_STANDALONE=ON"
echo -n " -DCMAKE_C_COMPILER=$PWD/stage1/bin/clang.exe -DCMAKE_C_COMPILER_WORKS=1 -DCMAKE_CXX_COMPILER=$PWD/llvm/bin/clang++.exe -DCMAKE_CXX_COMPILER_WORKS=1 -DLEAN_CXX_STDLIB='-lc++ -lc++abi'"
echo -n " -DSTAGE0_CMAKE_C_COMPILER=clang -DSTAGE0_CMAKE_CXX_COMPILER=clang++"
echo -n " -DLEAN_EXTRA_CXX_FLAGS='--sysroot $PWD/llvm -idirafter /clang64/include/'"
echo -n " -DLEANC_INTERNAL_FLAGS='--sysroot ROOT -nostdinc -isystem ROOT/include/clang' -DLEANC_CC=ROOT/bin/clang.exe"
echo -n " -DLEANC_INTERNAL_LINKER_FLAGS='-L ROOT/lib -static-libgcc -Wl,-Bstatic -lgmp $(pkg-config --static --libs libuv) -lunwind -Wl,-Bdynamic -fuse-ld=lld'"
# when not using the above flags, link GMP dynamically/as usual. Always link ICU dynamically.
echo -n " -DLEAN_EXTRA_LINKER_FLAGS='-lgmp $(pkg-config --libs libuv) -lucrtbase'"
echo -n " -DLEANC_INTERNAL_LINKER_FLAGS='-L ROOT/lib -static-libgcc -Wl,-Bstatic -lgmp -luv -lunwind -Wl,-Bdynamic -fuse-ld=lld'"
# when not using the above flags, link GMP dynamically/as usual
echo -n " -DLEAN_EXTRA_LINKER_FLAGS='-lgmp -luv -lucrtbase'"
# do not set `LEAN_CC` for tests
echo -n " -DAUTO_THREAD_FINALIZATION=OFF -DSTAGE0_AUTO_THREAD_FINALIZATION=OFF"
echo -n " -DLEAN_TEST_VARS=''"

View File

@@ -10,7 +10,7 @@ endif()
include(ExternalProject)
project(LEAN CXX C)
set(LEAN_VERSION_MAJOR 4)
set(LEAN_VERSION_MINOR 15)
set(LEAN_VERSION_MINOR 12)
set(LEAN_VERSION_PATCH 0)
set(LEAN_VERSION_IS_RELEASE 0) # This number is 1 in the release revision, and 0 otherwise.
set(LEAN_SPECIAL_VERSION_DESC "" CACHE STRING "Additional version description like 'nightly-2018-03-11'")
@@ -155,10 +155,6 @@ endif ()
# We want explicit stack probes in huge Lean stack frames for robust stack overflow detection
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_FLAGS " -fwrapv")
if(NOT MULTI_THREAD)
message(STATUS "Disabled multi-thread support, it will not be safe to run multiple threads in parallel")
set(AUTO_THREAD_FINALIZATION OFF)
@@ -247,77 +243,15 @@ if("${USE_GMP}" MATCHES "ON")
endif()
endif()
# LibUV
if("${CMAKE_SYSTEM_NAME}" MATCHES "Emscripten")
# Only on WebAssembly we compile LibUV ourselves
set(LIBUV_EMSCRIPTEN_FLAGS "${EMSCRIPTEN_SETTINGS}")
# LibUV does not compile on WebAssembly without modifications because
# building LibUV on a platform requires including stub implementations
# for features not present on the target platform. This patch includes
# the minimum amount of stub implementations needed for successfully
# running Lean on WebAssembly and using LibUV's temporary file support.
# It still leaves several symbols completely undefined: uv__fs_event_close,
# uv__hrtime, uv__io_check_fd, uv__io_fork, uv__io_poll, uv__platform_invalidate_fd
# uv__platform_loop_delete, uv__platform_loop_init. Making additional
# LibUV features available on WebAssembly might require adapting the
# patch to include additional LibUV source files.
set(LIBUV_PATCH_IN "
diff --git a/CMakeLists.txt b/CMakeLists.txt
index 5e8e0166..f3b29134 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -317,6 +317,11 @@ if(CMAKE_SYSTEM_NAME STREQUAL \"GNU\")
src/unix/hurd.c)
endif()
+if(CMAKE_SYSTEM_NAME STREQUAL \"Emscripten\")
+ list(APPEND uv_sources
+ src/unix/no-proctitle.c)
+endif()
+
if(CMAKE_SYSTEM_NAME STREQUAL \"Linux\")
list(APPEND uv_defines _GNU_SOURCE _POSIX_C_SOURCE=200112)
list(APPEND uv_libraries dl rt)
")
string(REPLACE "\n" "\\n" LIBUV_PATCH ${LIBUV_PATCH_IN})
ExternalProject_add(libuv
PREFIX libuv
GIT_REPOSITORY https://github.com/libuv/libuv
# Sync version with flake.nix
GIT_TAG v1.48.0
CMAKE_ARGS -DCMAKE_BUILD_TYPE=Release -DLIBUV_BUILD_TESTS=OFF -DLIBUV_BUILD_SHARED=OFF -DCMAKE_AR=${CMAKE_AR} -DCMAKE_TOOLCHAIN_FILE=${CMAKE_TOOLCHAIN_FILE} -DCMAKE_POSITION_INDEPENDENT_CODE=ON -DCMAKE_C_FLAGS=${LIBUV_EMSCRIPTEN_FLAGS}
PATCH_COMMAND git reset --hard HEAD && printf "${LIBUV_PATCH}" > patch.diff && git apply patch.diff
BUILD_IN_SOURCE ON
INSTALL_COMMAND "")
set(LIBUV_INCLUDE_DIR "${CMAKE_BINARY_DIR}/libuv/src/libuv/include")
set(LIBUV_LIBRARIES "${CMAKE_BINARY_DIR}/libuv/src/libuv/libuv.a")
else()
if(NOT "${CMAKE_SYSTEM_NAME}" MATCHES "Emscripten")
# LibUV
find_package(LibUV 1.0.0 REQUIRED)
include_directories(${LIBUV_INCLUDE_DIR})
endif()
include_directories(${LIBUV_INCLUDE_DIR})
if(NOT LEAN_STANDALONE)
string(APPEND LEAN_EXTRA_LINKER_FLAGS " ${LIBUV_LIBRARIES}")
endif()
# Windows SDK (for ICU)
if(${CMAKE_SYSTEM_NAME} MATCHES "Windows")
# Pass 'tools' to skip MSVC version check (as MSVC/Visual Studio is not necessarily installed)
find_package(WindowsSDK REQUIRED COMPONENTS tools)
# This will give a semicolon-separated list of include directories
get_windowssdk_include_dirs(${WINDOWSSDK_LATEST_DIR} WINDOWSSDK_INCLUDE_DIRS)
# To successfully build against Windows SDK headers, the Windows SDK headers must have lower
# priority than other system headers, so use `-idirafter`. Unfortunately, CMake does not
# support this using `include_directories`.
string(REPLACE ";" "\" -idirafter \"" WINDOWSSDK_INCLUDE_DIRS "${WINDOWSSDK_INCLUDE_DIRS}")
string(APPEND CMAKE_CXX_FLAGS " -idirafter \"${WINDOWSSDK_INCLUDE_DIRS}\"")
string(APPEND LEAN_EXTRA_LINKER_FLAGS " -licu")
endif()
# ccache
if(CCACHE AND NOT CMAKE_CXX_COMPILER_LAUNCHER AND NOT CMAKE_C_COMPILER_LAUNCHER)
find_program(CCACHE_PATH ccache)
@@ -501,7 +435,7 @@ endif()
# Git HASH
if(USE_GITHASH)
include(GetGitRevisionDescription)
get_git_head_revision(GIT_REFSPEC GIT_SHA1 ALLOW_LOOKING_ABOVE_CMAKE_SOURCE_DIR)
get_git_head_revision(GIT_REFSPEC GIT_SHA1)
if(${GIT_SHA1} MATCHES "GITDIR-NOTFOUND")
message(STATUS "Failed to read git_sha1")
set(GIT_SHA1 "")
@@ -588,10 +522,6 @@ if(${STAGE} GREATER 1)
endif()
else()
add_subdirectory(runtime)
if("${CMAKE_SYSTEM_NAME}" MATCHES "Emscripten")
add_dependencies(leanrt libuv)
add_dependencies(leanrt_initial-exec libuv)
endif()
add_subdirectory(util)
set(LEAN_OBJS ${LEAN_OBJS} $<TARGET_OBJECTS:util>)
@@ -632,10 +562,7 @@ if (${CMAKE_SYSTEM_NAME} MATCHES "Emscripten")
# simple. (And we are not interested in `Lake` anyway.) To use dynamic
# linking, we would probably have to set MAIN_MODULE=2 on `leanshared`,
# SIDE_MODULE=2 on `lean`, and set CMAKE_SHARED_LIBRARY_SUFFIX to ".js".
# We set `ERROR_ON_UNDEFINED_SYMBOLS=0` because our build of LibUV does not
# define all symbols, see the comment about LibUV on WebAssembly further up
# in this file.
string(APPEND LEAN_EXE_LINKER_FLAGS " ${LIB}/temp/libleanshell.a ${TOOLCHAIN_STATIC_LINKER_FLAGS} ${EMSCRIPTEN_SETTINGS} -lnodefs.js -s EXIT_RUNTIME=1 -s MAIN_MODULE=1 -s LINKABLE=1 -s EXPORT_ALL=1 -s ERROR_ON_UNDEFINED_SYMBOLS=0")
string(APPEND LEAN_EXE_LINKER_FLAGS " ${LIB}/temp/libleanshell.a ${TOOLCHAIN_STATIC_LINKER_FLAGS} ${EMSCRIPTEN_SETTINGS} -lnodefs.js -s EXIT_RUNTIME=1 -s MAIN_MODULE=1 -s LINKABLE=1 -s EXPORT_ALL=1")
endif()
# Build the compiler using the bootstrapped C sources for stage0, and use

View File

@@ -35,4 +35,3 @@ import Init.Ext
import Init.Omega
import Init.MacroTrace
import Init.Grind
import Init.While

View File

@@ -80,8 +80,6 @@ noncomputable scoped instance (priority := low) propDecidable (a : Prop) : Decid
noncomputable def decidableInhabited (a : Prop) : Inhabited (Decidable a) where
default := inferInstance
instance (a : Prop) : Nonempty (Decidable a) := propDecidable a
noncomputable def typeDecidableEq (α : Sort u) : DecidableEq α :=
fun _ _ => inferInstance

View File

@@ -8,42 +8,6 @@ import Init.Core
universe u v w
/--
A `ForIn'` instance, which handles `for h : x in c do`,
can also handle `for x in x do` by ignoring `h`, and so provides a `ForIn` instance.
Note that this instance will cause a potentially non-defeq duplication if both `ForIn` and `ForIn'`
instances are provided for the same type.
-/
-- We set the priority to 500 so it is below the default,
-- but still above the low priority instance from `Stream`.
instance (priority := 500) instForInOfForIn' [ForIn' m ρ α d] : ForIn m ρ α where
forIn x b f := forIn' x b fun a _ => f a
@[simp] theorem forIn'_eq_forIn [d : Membership α ρ] [ForIn' m ρ α d] {β} [Monad m] (x : ρ) (b : β)
(f : (a : α) a x β m (ForInStep β)) (g : (a : α) β m (ForInStep β))
(h : a m b, f a m b = g a b) :
forIn' x b f = forIn x b g := by
simp [instForInOfForIn']
congr
apply funext
intro a
apply funext
intro m
apply funext
intro b
simp [h]
rfl
/-- Extract the value from a `ForInStep`, ignoring whether it is `done` or `yield`. -/
def ForInStep.value (x : ForInStep α) : α :=
match x with
| ForInStep.done b => b
| ForInStep.yield b => b
@[simp] theorem ForInStep.value_done (b : β) : (ForInStep.done b).value = b := rfl
@[simp] theorem ForInStep.value_yield (b : β) : (ForInStep.yield b).value = b := rfl
@[reducible]
def Functor.mapRev {f : Type u Type v} [Functor f] {α β : Type u} : f α (α β) f β :=
fun a f => f <$> a

View File

@@ -33,10 +33,6 @@ attribute [simp] id_map
@[simp] theorem id_map' [Functor m] [LawfulFunctor m] (x : m α) : (fun a => a) <$> x = x :=
id_map x
@[simp] theorem Functor.map_map [Functor f] [LawfulFunctor f] (m : α β) (g : β γ) (x : f α) :
g <$> m <$> x = (fun a => g (m a)) <$> x :=
(comp_map _ _ _).symm
/--
The `Applicative` typeclass only contains the operations of an applicative functor.
`LawfulApplicative` further asserts that these operations satisfy the laws of an applicative functor:
@@ -87,16 +83,12 @@ class LawfulMonad (m : Type u → Type v) [Monad m] extends LawfulApplicative m
seq_assoc x g h := (by simp [ bind_pure_comp, bind_map, bind_assoc, pure_bind])
export LawfulMonad (bind_pure_comp bind_map pure_bind bind_assoc)
attribute [simp] pure_bind bind_assoc bind_pure_comp
attribute [simp] pure_bind bind_assoc
@[simp] theorem bind_pure [Monad m] [LawfulMonad m] (x : m α) : x >>= pure = x := by
show x >>= (fun a => pure (id a)) = x
rw [bind_pure_comp, id_map]
/--
Use `simp [← bind_pure_comp]` rather than `simp [map_eq_pure_bind]`,
as `bind_pure_comp` is in the default simp set, so also using `map_eq_pure_bind` would cause a loop.
-/
theorem map_eq_pure_bind [Monad m] [LawfulMonad m] (f : α β) (x : m α) : f <$> x = x >>= fun a => pure (f a) := by
rw [ bind_pure_comp]
@@ -117,24 +109,10 @@ theorem seq_eq_bind {α β : Type u} [Monad m] [LawfulMonad m] (mf : m (α
theorem seqRight_eq_bind [Monad m] [LawfulMonad m] (x : m α) (y : m β) : x *> y = x >>= fun _ => y := by
rw [seqRight_eq]
simp only [map_eq_pure_bind, const, seq_eq_bind_map, bind_assoc, pure_bind, id_eq, bind_pure]
simp [map_eq_pure_bind, seq_eq_bind_map, const]
theorem seqLeft_eq_bind [Monad m] [LawfulMonad m] (x : m α) (y : m β) : x <* y = x >>= fun a => y >>= fun _ => pure a := by
rw [seqLeft_eq]
simp only [map_eq_pure_bind, seq_eq_bind_map, bind_assoc, pure_bind, const_apply]
@[simp] theorem map_bind [Monad m] [LawfulMonad m] (f : β γ) (x : m α) (g : α m β) :
f <$> (x >>= g) = x >>= fun a => f <$> g a := by
rw [ bind_pure_comp, LawfulMonad.bind_assoc]
simp [bind_pure_comp]
@[simp] theorem bind_map_left [Monad m] [LawfulMonad m] (f : α β) (x : m α) (g : β m γ) :
((f <$> x) >>= fun b => g b) = (x >>= fun a => g (f a)) := by
rw [ bind_pure_comp]
simp only [bind_assoc, pure_bind]
@[simp] theorem Functor.map_unit [Monad m] [LawfulMonad m] {a : m PUnit} : (fun _ => PUnit.unit) <$> a = a := by
simp [map]
rw [seqLeft_eq]; simp [map_eq_pure_bind, seq_eq_bind_map]
/--
An alternative constructor for `LawfulMonad` which has more
@@ -183,9 +161,9 @@ end Id
instance : LawfulMonad Option := LawfulMonad.mk'
(id_map := fun x => by cases x <;> rfl)
(pure_bind := fun _ _ => rfl)
(bind_assoc := fun x _ _ => by cases x <;> rfl)
(bind_pure_comp := fun _ x => by cases x <;> rfl)
(pure_bind := fun x f => rfl)
(bind_assoc := fun x f g => by cases x <;> rfl)
(bind_pure_comp := fun f x => by cases x <;> rfl)
instance : LawfulApplicative Option := inferInstance
instance : LawfulFunctor Option := inferInstance

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@@ -25,7 +25,7 @@ theorem ext {x y : ExceptT ε m α} (h : x.run = y.run) : x = y := by
@[simp] theorem run_throw [Monad m] : run (throw e : ExceptT ε m β) = pure (Except.error e) := rfl
@[simp] theorem run_bind_lift [Monad m] [LawfulMonad m] (x : m α) (f : α ExceptT ε m β) : run (ExceptT.lift x >>= f : ExceptT ε m β) = x >>= fun a => run (f a) := by
simp [ExceptT.run, ExceptT.lift, bind, ExceptT.bind, ExceptT.mk, ExceptT.bindCont]
simp[ExceptT.run, ExceptT.lift, bind, ExceptT.bind, ExceptT.mk, ExceptT.bindCont, map_eq_pure_bind]
@[simp] theorem bind_throw [Monad m] [LawfulMonad m] (f : α ExceptT ε m β) : (throw e >>= f) = throw e := by
simp [throw, throwThe, MonadExceptOf.throw, bind, ExceptT.bind, ExceptT.bindCont, ExceptT.mk]
@@ -43,7 +43,7 @@ theorem run_bind [Monad m] (x : ExceptT ε m α)
@[simp] theorem run_map [Monad m] [LawfulMonad m] (f : α β) (x : ExceptT ε m α)
: (f <$> x).run = Except.map f <$> x.run := by
simp [Functor.map, ExceptT.map, bind_pure_comp]
simp [Functor.map, ExceptT.map, map_eq_pure_bind]
apply bind_congr
intro a; cases a <;> simp [Except.map]
@@ -62,7 +62,7 @@ protected theorem seqLeft_eq {α β ε : Type u} {m : Type u → Type v} [Monad
intro
| Except.error _ => simp
| Except.ok _ =>
simp [bind_pure_comp]; apply bind_congr; intro b;
simp [map_eq_pure_bind]; apply bind_congr; intro b;
cases b <;> simp [comp, Except.map, const]
protected theorem seqRight_eq [Monad m] [LawfulMonad m] (x : ExceptT ε m α) (y : ExceptT ε m β) : x *> y = const α id <$> x <*> y := by
@@ -84,19 +84,14 @@ instance [Monad m] [LawfulMonad m] : LawfulMonad (ExceptT ε m) where
pure_bind := by intros; apply ext; simp [run_bind]
bind_assoc := by intros; apply ext; simp [run_bind]; apply bind_congr; intro a; cases a <;> simp
@[simp] theorem map_throw [Monad m] [LawfulMonad m] {α β : Type _} (f : α β) (e : ε) :
f <$> (throw e : ExceptT ε m α) = (throw e : ExceptT ε m β) := by
simp only [ExceptT.instMonad, ExceptT.map, ExceptT.mk, throw, throwThe, MonadExceptOf.throw,
pure_bind]
end ExceptT
/-! # Except -/
instance : LawfulMonad (Except ε) := LawfulMonad.mk'
(id_map := fun x => by cases x <;> rfl)
(pure_bind := fun _ _ => rfl)
(bind_assoc := fun a _ _ => by cases a <;> rfl)
(pure_bind := fun a f => rfl)
(bind_assoc := fun a f g => by cases a <;> rfl)
instance : LawfulApplicative (Except ε) := inferInstance
instance : LawfulFunctor (Except ε) := inferInstance
@@ -180,7 +175,7 @@ theorem ext {x y : StateT σ m α} (h : ∀ s, x.run s = y.run s) : x = y :=
simp [bind, StateT.bind, run]
@[simp] theorem run_map {α β σ : Type u} [Monad m] [LawfulMonad m] (f : α β) (x : StateT σ m α) (s : σ) : (f <$> x).run s = (fun (p : α × σ) => (f p.1, p.2)) <$> x.run s := by
simp [Functor.map, StateT.map, run, bind_pure_comp]
simp [Functor.map, StateT.map, run, map_eq_pure_bind]
@[simp] theorem run_get [Monad m] (s : σ) : (get : StateT σ m σ).run s = pure (s, s) := rfl
@@ -215,13 +210,13 @@ theorem run_bind_lift {α σ : Type u} [Monad m] [LawfulMonad m] (x : m α) (f :
theorem seqRight_eq [Monad m] [LawfulMonad m] (x : StateT σ m α) (y : StateT σ m β) : x *> y = const α id <$> x <*> y := by
apply ext; intro s
simp [bind_pure_comp, const]
simp [map_eq_pure_bind, const]
apply bind_congr; intro p; cases p
simp [Prod.eta]
theorem seqLeft_eq [Monad m] [LawfulMonad m] (x : StateT σ m α) (y : StateT σ m β) : x <* y = const β <$> x <*> y := by
apply ext; intro s
simp [bind_pure_comp]
simp [map_eq_pure_bind]
instance [Monad m] [LawfulMonad m] : LawfulMonad (StateT σ m) where
id_map := by intros; apply ext; intros; simp[Prod.eta]
@@ -229,7 +224,7 @@ instance [Monad m] [LawfulMonad m] : LawfulMonad (StateT σ m) where
seqLeft_eq := seqLeft_eq
seqRight_eq := seqRight_eq
pure_seq := by intros; apply ext; intros; simp
bind_pure_comp := by intros; apply ext; intros; simp
bind_pure_comp := by intros; apply ext; intros; simp; apply LawfulMonad.bind_pure_comp
bind_map := by intros; rfl
pure_bind := by intros; apply ext; intros; simp
bind_assoc := by intros; apply ext; intros; simp

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@@ -6,7 +6,8 @@ Authors: Leonardo de Moura, Sebastian Ullrich
The State monad transformer using IO references.
-/
prelude
import Init.System.ST
import Init.System.IO
import Init.Control.State
def StateRefT' (ω : Type) (σ : Type) (m : Type Type) (α : Type) : Type := ReaderT (ST.Ref ω σ) m α

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@@ -7,7 +7,6 @@ Notation for operators defined at Prelude.lean
-/
prelude
import Init.Tactics
import Init.Meta
namespace Lean.Parser.Tactic.Conv
@@ -47,20 +46,12 @@ scoped syntax (name := withAnnotateState)
/-- `skip` does nothing. -/
syntax (name := skip) "skip" : conv
/--
Traverses into the left subterm of a binary operator.
In general, for an `n`-ary operator, it traverses into the second to last argument.
It is a synonym for `arg -2`.
-/
/-- Traverses into the left subterm of a binary operator.
(In general, for an `n`-ary operator, it traverses into the second to last argument.) -/
syntax (name := lhs) "lhs" : conv
/--
Traverses into the right subterm of a binary operator.
In general, for an `n`-ary operator, it traverses into the last argument.
It is a synonym for `arg -1`.
-/
/-- Traverses into the right subterm of a binary operator.
(In general, for an `n`-ary operator, it traverses into the last argument.) -/
syntax (name := rhs) "rhs" : conv
/-- Traverses into the function of a (unary) function application.
@@ -83,17 +74,13 @@ subgoals for all the function arguments. For example, if the target is `f x y` t
`congr` produces two subgoals, one for `x` and one for `y`. -/
syntax (name := congr) "congr" : conv
syntax argArg := "@"? "-"? num
/--
* `arg i` traverses into the `i`'th argument of the target. For example if the
target is `f a b c d` then `arg 1` traverses to `a` and `arg 3` traverses to `c`.
The index may be negative; `arg -1` traverses into the last argument,
`arg -2` into the second-to-last argument, and so on.
* `arg @i` is the same as `arg i` but it counts all arguments instead of just the
explicit arguments.
* `arg 0` traverses into the function. If the target is `f a b c d`, `arg 0` traverses into `f`. -/
syntax (name := arg) "arg " argArg : conv
syntax (name := arg) "arg " "@"? num : conv
/-- `ext x` traverses into a binder (a `fun x => e` or `∀ x, e` expression)
to target `e`, introducing name `x` in the process. -/
@@ -143,11 +130,11 @@ For example, if we are searching for `f _` in `f (f a) = f b`:
syntax (name := pattern) "pattern " (occs)? term : conv
/-- `rw [thm]` rewrites the target using `thm`. See the `rw` tactic for more information. -/
syntax (name := rewrite) "rewrite" optConfig rwRuleSeq : conv
syntax (name := rewrite) "rewrite" (config)? rwRuleSeq : conv
/-- `simp [thm]` performs simplification using `thm` and marked `@[simp]` lemmas.
See the `simp` tactic for more information. -/
syntax (name := simp) "simp" optConfig (discharger)? (&" only")?
syntax (name := simp) "simp" (config)? (discharger)? (&" only")?
(" [" withoutPosition((simpStar <|> simpErase <|> simpLemma),*) "]")? : conv
/--
@@ -164,7 +151,7 @@ example (a : Nat): (0 + 0) = a - a := by
rw [← Nat.sub_self a]
```
-/
syntax (name := dsimp) "dsimp" optConfig (discharger)? (&" only")?
syntax (name := dsimp) "dsimp" (config)? (discharger)? (&" only")?
(" [" withoutPosition((simpErase <|> simpLemma),*) "]")? : conv
/-- `simp_match` simplifies match expressions. For example,
@@ -260,12 +247,12 @@ macro (name := failIfSuccess) tk:"fail_if_success " s:convSeq : conv =>
/-- `rw [rules]` applies the given list of rewrite rules to the target.
See the `rw` tactic for more information. -/
macro "rw" c:optConfig s:rwRuleSeq : conv => `(conv| rewrite $c:optConfig $s)
macro "rw" c:(config)? s:rwRuleSeq : conv => `(conv| rewrite $[$c]? $s)
/-- `erw [rules]` is a shorthand for `rw (transparency := .default) [rules]`.
/-- `erw [rules]` is a shorthand for `rw (config := { transparency := .default }) [rules]`.
This does rewriting up to unfolding of regular definitions (by comparison to regular `rw`
which only unfolds `@[reducible]` definitions). -/
macro "erw" c:optConfig s:rwRuleSeq : conv => `(conv| rw $[$(getConfigItems c)]* (transparency := .default) $s:rwRuleSeq)
macro "erw" s:rwRuleSeq : conv => `(conv| rw (config := { transparency := .default }) $s)
/-- `args` traverses into all arguments. Synonym for `congr`. -/
macro "args" : conv => `(conv| congr)
@@ -276,7 +263,7 @@ macro "right" : conv => `(conv| rhs)
/-- `intro` traverses into binders. Synonym for `ext`. -/
macro "intro" xs:(ppSpace colGt ident)* : conv => `(conv| ext $xs*)
syntax enterArg := ident <|> argArg
syntax enterArg := ident <|> ("@"? num)
/-- `enter [arg, ...]` is a compact way to describe a path to a subterm.
It is a shorthand for other conv tactics as follows:
@@ -285,7 +272,12 @@ It is a shorthand for other conv tactics as follows:
* `enter [x]` (where `x` is an identifier) is equivalent to `ext x`.
For example, given the target `f (g a (fun x => x b))`, `enter [1, 2, x, 1]`
will traverse to the subterm `b`. -/
syntax (name := enter) "enter" " [" withoutPosition(enterArg,+) "]" : conv
syntax "enter" " [" withoutPosition(enterArg,+) "]" : conv
macro_rules
| `(conv| enter [$i:num]) => `(conv| arg $i)
| `(conv| enter [@$i]) => `(conv| arg @$i)
| `(conv| enter [$id:ident]) => `(conv| ext $id)
| `(conv| enter [$arg, $args,*]) => `(conv| (enter [$arg]; enter [$args,*]))
/-- The `apply thm` conv tactic is the same as `apply thm` the tactic.
There are no restrictions on `thm`, but strange results may occur if `thm`

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@@ -324,6 +324,7 @@ class ForIn' (m : Type u₁ → Type u₂) (ρ : Type u) (α : outParam (Type v)
export ForIn' (forIn')
/--
Auxiliary type used to compile `do` notation. It is used when compiling a do block
nested inside a combinator like `tryCatch`. It encodes the possible ways the
@@ -822,7 +823,6 @@ theorem iff_iff_implies_and_implies {a b : Prop} : (a ↔ b) ↔ (a → b) ∧ (
protected theorem Iff.rfl {a : Prop} : a a :=
Iff.refl a
-- And, also for backward compatibility, we try `Iff.rfl.` using `exact` (see #5366)
macro_rules | `(tactic| rfl) => `(tactic| exact Iff.rfl)
theorem Iff.of_eq (h : a = b) : a b := h Iff.rfl
@@ -837,9 +837,6 @@ instance : Trans Iff Iff Iff where
theorem Eq.comm {a b : α} : a = b b = a := Iff.intro Eq.symm Eq.symm
theorem eq_comm {a b : α} : a = b b = a := Eq.comm
theorem HEq.comm {a : α} {b : β} : HEq a b HEq b a := Iff.intro HEq.symm HEq.symm
theorem heq_comm {a : α} {b : β} : HEq a b HEq b a := HEq.comm
@[symm] theorem Iff.symm (h : a b) : b a := Iff.intro h.mpr h.mp
theorem Iff.comm: (a b) (b a) := Iff.intro Iff.symm Iff.symm
theorem iff_comm : (a b) (b a) := Iff.comm
@@ -1384,7 +1381,6 @@ gen_injective_theorems% Except
gen_injective_theorems% EStateM.Result
gen_injective_theorems% Lean.Name
gen_injective_theorems% Lean.Syntax
gen_injective_theorems% BitVec
theorem Nat.succ.inj {m n : Nat} : m.succ = n.succ m = n :=
fun x => Nat.noConfusion x id
@@ -1864,8 +1860,7 @@ section
variable {α : Type u}
variable (r : α α Prop)
instance Quotient.decidableEq {α : Sort u} {s : Setoid α} [d : (a b : α), Decidable (a b)]
: DecidableEq (Quotient s) :=
instance {α : Sort u} {s : Setoid α} [d : (a b : α), Decidable (a b)] : DecidableEq (Quotient s) :=
fun (q₁ q₂ : Quotient s) =>
Quotient.recOnSubsingleton₂ q₁ q₂
fun a₁ a₂ =>
@@ -1936,6 +1931,15 @@ instance : Subsingleton (Squash α) where
apply Quot.sound
trivial
/-! # Relations -/
/--
`Antisymm (·≤·)` says that `(·≤·)` is antisymmetric, that is, `a ≤ b → b ≤ a → a = b`.
-/
class Antisymm {α : Sort u} (r : α α Prop) : Prop where
/-- An antisymmetric relation `(·≤·)` satisfies `a ≤ b → b ≤ a → a = b`. -/
antisymm {a b : α} : r a b r b a a = b
namespace Lean
/-! # Kernel reduction hints -/
@@ -2111,14 +2115,4 @@ instance : Commutative Or := ⟨fun _ _ => propext or_comm⟩
instance : Commutative And := fun _ _ => propext and_comm
instance : Commutative Iff := fun _ _ => propext iff_comm
/--
`Antisymm (·≤·)` says that `(·≤·)` is antisymmetric, that is, `a ≤ b → b ≤ a → a = b`.
-/
class Antisymm (r : α α Prop) : Prop where
/-- An antisymmetric relation `(·≤·)` satisfies `a ≤ b → b ≤ a → a = b`. -/
antisymm {a b : α} : r a b r b a a = b
@[deprecated Antisymm (since := "2024-10-16"), inherit_doc Antisymm]
abbrev _root_.Antisymm (r : α α Prop) : Prop := Std.Antisymm r
end Std

View File

@@ -19,7 +19,6 @@ import Init.Data.ByteArray
import Init.Data.FloatArray
import Init.Data.Fin
import Init.Data.UInt
import Init.Data.SInt
import Init.Data.Float
import Init.Data.Option
import Init.Data.Ord
@@ -41,4 +40,3 @@ import Init.Data.ULift
import Init.Data.PLift
import Init.Data.Zero
import Init.Data.NeZero
import Init.Data.Function

View File

@@ -16,4 +16,3 @@ import Init.Data.Array.Lemmas
import Init.Data.Array.TakeDrop
import Init.Data.Array.Bootstrap
import Init.Data.Array.GetLit
import Init.Data.Array.MapIdx

View File

@@ -5,7 +5,6 @@ Authors: Joachim Breitner, Mario Carneiro
-/
prelude
import Init.Data.Array.Mem
import Init.Data.Array.Lemmas
import Init.Data.List.Attach
namespace Array
@@ -27,152 +26,4 @@ Unsafe implementation of `attachWith`, taking advantage of the fact that the rep
with the same elements but in the type `{x // x ∈ xs}`. -/
@[inline] def attach (xs : Array α) : Array {x // x xs} := xs.attachWith _ fun _ => id
@[simp] theorem _root_.List.attachWith_toArray {l : List α} {P : α Prop} {H : x l.toArray, P x} :
l.toArray.attachWith P H = (l.attachWith P (by simpa using H)).toArray := by
simp [attachWith]
@[simp] theorem _root_.List.attach_toArray {l : List α} :
l.toArray.attach = (l.attachWith (· l.toArray) (by simp)).toArray := by
simp [attach]
@[simp] theorem toList_attachWith {l : Array α} {P : α Prop} {H : x l, P x} :
(l.attachWith P H).toList = l.toList.attachWith P (by simpa [mem_toList] using H) := by
simp [attachWith]
@[simp] theorem toList_attach {α : Type _} {l : Array α} :
l.attach.toList = l.toList.attachWith (· l) (by simp [mem_toList]) := by
simp [attach]
/-! ## unattach
`Array.unattach` is the (one-sided) inverse of `Array.attach`. It is a synonym for `Array.map Subtype.val`.
We use it by providing a simp lemma `l.attach.unattach = l`, and simp lemmas which recognize higher order
functions applied to `l : Array { x // p x }` which only depend on the value, not the predicate, and rewrite these
in terms of a simpler function applied to `l.unattach`.
Further, we provide simp lemmas that push `unattach` inwards.
-/
/--
A synonym for `l.map (·.val)`. Mostly this should not be needed by users.
It is introduced as in intermediate step by lemmas such as `map_subtype`,
and is ideally subsequently simplified away by `unattach_attach`.
If not, usually the right approach is `simp [Array.unattach, -Array.map_subtype]` to unfold.
-/
def unattach {α : Type _} {p : α Prop} (l : Array { x // p x }) := l.map (·.val)
@[simp] theorem unattach_nil {p : α Prop} : (#[] : Array { x // p x }).unattach = #[] := rfl
@[simp] theorem unattach_push {p : α Prop} {a : { x // p x }} {l : Array { x // p x }} :
(l.push a).unattach = l.unattach.push a.1 := by
simp only [unattach, Array.map_push]
@[simp] theorem size_unattach {p : α Prop} {l : Array { x // p x }} :
l.unattach.size = l.size := by
unfold unattach
simp
@[simp] theorem _root_.List.unattach_toArray {p : α Prop} {l : List { x // p x }} :
l.toArray.unattach = l.unattach.toArray := by
simp only [unattach, List.map_toArray, List.unattach]
@[simp] theorem toList_unattach {p : α Prop} {l : Array { x // p x }} :
l.unattach.toList = l.toList.unattach := by
simp only [unattach, toList_map, List.unattach]
@[simp] theorem unattach_attach {l : Array α} : l.attach.unattach = l := by
cases l
simp
@[simp] theorem unattach_attachWith {p : α Prop} {l : Array α}
{H : a l, p a} :
(l.attachWith p H).unattach = l := by
cases l
simp
/-! ### Recognizing higher order functions using a function that only depends on the value. -/
/--
This lemma identifies folds over arrays of subtypes, where the function only depends on the value, not the proposition,
and simplifies these to the function directly taking the value.
-/
theorem foldl_subtype {p : α Prop} {l : Array { x // p x }}
{f : β { x // p x } β} {g : β α β} {x : β}
{hf : b x h, f b x, h = g b x} :
l.foldl f x = l.unattach.foldl g x := by
cases l
simp only [List.foldl_toArray', List.unattach_toArray]
rw [List.foldl_subtype] -- Why can't simp do this?
simp [hf]
/-- Variant of `foldl_subtype` with side condition to check `stop = l.size`. -/
@[simp] theorem foldl_subtype' {p : α Prop} {l : Array { x // p x }}
{f : β { x // p x } β} {g : β α β} {x : β}
{hf : b x h, f b x, h = g b x} (h : stop = l.size) :
l.foldl f x 0 stop = l.unattach.foldl g x := by
subst h
rwa [foldl_subtype]
/--
This lemma identifies folds over arrays of subtypes, where the function only depends on the value, not the proposition,
and simplifies these to the function directly taking the value.
-/
theorem foldr_subtype {p : α Prop} {l : Array { x // p x }}
{f : { x // p x } β β} {g : α β β} {x : β}
{hf : x h b, f x, h b = g x b} :
l.foldr f x = l.unattach.foldr g x := by
cases l
simp only [List.foldr_toArray', List.unattach_toArray]
rw [List.foldr_subtype]
simp [hf]
/-- Variant of `foldr_subtype` with side condition to check `stop = l.size`. -/
@[simp] theorem foldr_subtype' {p : α Prop} {l : Array { x // p x }}
{f : { x // p x } β β} {g : α β β} {x : β}
{hf : x h b, f x, h b = g x b} (h : start = l.size) :
l.foldr f x start 0 = l.unattach.foldr g x := by
subst h
rwa [foldr_subtype]
/--
This lemma identifies maps over arrays of subtypes, where the function only depends on the value, not the proposition,
and simplifies these to the function directly taking the value.
-/
@[simp] theorem map_subtype {p : α Prop} {l : Array { x // p x }}
{f : { x // p x } β} {g : α β} {hf : x h, f x, h = g x} :
l.map f = l.unattach.map g := by
cases l
simp only [List.map_toArray, List.unattach_toArray]
rw [List.map_subtype]
simp [hf]
@[simp] theorem filterMap_subtype {p : α Prop} {l : Array { x // p x }}
{f : { x // p x } Option β} {g : α Option β} {hf : x h, f x, h = g x} :
l.filterMap f = l.unattach.filterMap g := by
cases l
simp only [size_toArray, List.filterMap_toArray', List.unattach_toArray, List.length_unattach,
mk.injEq]
rw [List.filterMap_subtype]
simp [hf]
@[simp] theorem unattach_filter {p : α Prop} {l : Array { x // p x }}
{f : { x // p x } Bool} {g : α Bool} {hf : x h, f x, h = g x} :
(l.filter f).unattach = l.unattach.filter g := by
cases l
simp [hf]
/-! ### Simp lemmas pushing `unattach` inwards. -/
@[simp] theorem unattach_reverse {p : α Prop} {l : Array { x // p x }} :
l.reverse.unattach = l.unattach.reverse := by
cases l
simp
@[simp] theorem unattach_append {p : α Prop} {l₁ l₂ : Array { x // p x }} :
(l₁ ++ l₂).unattach = l₁.unattach ++ l₂.unattach := by
cases l₁
cases l₂
simp
end Array

View File

@@ -7,11 +7,10 @@ prelude
import Init.WFTactics
import Init.Data.Nat.Basic
import Init.Data.Fin.Basic
import Init.Data.UInt.BasicAux
import Init.Data.UInt.Basic
import Init.Data.Repr
import Init.Data.ToString.Basic
import Init.GetElem
import Init.Data.List.ToArray
universe u v w
/-! ### Array literal syntax -/
@@ -25,8 +24,6 @@ variable {α : Type u}
namespace Array
@[deprecated toList (since := "2024-10-13")] abbrev data := @toList
/-! ### Preliminary theorems -/
@[simp] theorem size_set (a : Array α) (i : Fin a.size) (v : α) : (set a i v).size = a.size :=
@@ -80,42 +77,6 @@ theorem ext' {as bs : Array α} (h : as.toList = bs.toList) : as = bs := by
@[simp] theorem size_toArray (as : List α) : as.toArray.size = as.length := by simp [size]
@[simp] theorem getElem_toList {a : Array α} {i : Nat} (h : i < a.size) : 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.
structure Mem (as : Array α) (a : α) : Prop where
val : a as.toList
instance : Membership α (Array α) where
mem := Mem
theorem mem_def {a : α} {as : Array α} : a as a as.toList :=
fun | .mk h => h, Array.Mem.mk
@[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
end Array
namespace List
@[simp] theorem toArray_toList (a : Array α) : a.toList.toArray = a := rfl
@[simp] theorem getElem_toArray {a : List α} {i : Nat} (h : i < a.toArray.size) :
a.toArray[i] = a[i]'(by simpa using h) := rfl
@[simp] theorem getElem?_toArray {a : List α} {i : Nat} : a.toArray[i]? = a[i]? := rfl
@[simp] theorem getElem!_toArray [Inhabited α] {a : List α} {i : Nat} :
a.toArray[i]! = a[i]! := rfl
end List
namespace Array
@[deprecated toList_toArray (since := "2024-09-09")] abbrev data_toArray := @toList_toArray
@[deprecated Array.toList (since := "2024-09-10")] abbrev Array.data := @Array.toList
@@ -235,11 +196,9 @@ def range (n : Nat) : Array Nat :=
def singleton (v : α) : Array α :=
mkArray 1 v
def back! [Inhabited α] (a : Array α) : α :=
def back [Inhabited α] (a : Array α) : α :=
a.get! (a.size - 1)
@[deprecated back! (since := "2024-10-31")] abbrev back := @back!
def get? (a : Array α) (i : Nat) : Option α :=
if h : i < a.size then some a[i] else none
@@ -256,18 +215,15 @@ def swapAt! (a : Array α) (i : Nat) (v : α) : α × Array α :=
if h : i < a.size then
swapAt a i, h v
else
have : Inhabited (α × Array α) := (v, a)
have : Inhabited α := v
panic! ("index " ++ toString i ++ " out of bounds")
/-- `take a n` returns the first `n` elements of `a`. -/
def take (a : Array α) (n : Nat) : Array α :=
def shrink (a : Array α) (n : Nat) : Array α :=
let rec loop
| 0, a => a
| n+1, a => loop n a.pop
loop (a.size - n) a
@[deprecated take (since := "2024-10-22")] abbrev shrink := @take
@[inline]
unsafe def modifyMUnsafe [Monad m] (a : Array α) (i : Nat) (f : α m α) : m (Array α) := do
if h : i < a.size then
@@ -304,21 +260,21 @@ def modifyOp (self : Array α) (idx : Nat) (f : αα) : Array α :=
We claim this unsafe implementation is correct because an array cannot have more than `usizeSz` elements in our runtime.
This kind of low level trick can be removed with a little bit of compiler support. For example, if the compiler simplifies `as.size < usizeSz` to true. -/
@[inline] unsafe def forIn'Unsafe {α : Type u} {β : Type v} {m : Type v Type w} [Monad m] (as : Array α) (b : β) (f : (a : α) a as β m (ForInStep β)) : m β :=
@[inline] unsafe def forInUnsafe {α : Type u} {β : Type v} {m : Type v Type w} [Monad m] (as : Array α) (b : β) (f : α β m (ForInStep β)) : m β :=
let sz := as.usize
let rec @[specialize] loop (i : USize) (b : β) : m β := do
if i < sz then
let a := as.uget i lcProof
match ( f a lcProof b) with
match ( f a b) with
| ForInStep.done b => pure b
| ForInStep.yield b => loop (i+1) b
else
pure b
loop 0 b
/-- Reference implementation for `forIn'` -/
@[implemented_by Array.forIn'Unsafe]
protected def forIn' {α : Type u} {β : Type v} {m : Type v Type w} [Monad m] (as : Array α) (b : β) (f : (a : α) a as β m (ForInStep β)) : m β :=
/-- Reference implementation for `forIn` -/
@[implemented_by Array.forInUnsafe]
protected def forIn {α : Type u} {β : Type v} {m : Type v Type w} [Monad m] (as : Array α) (b : β) (f : α β m (ForInStep β)) : m β :=
let rec loop (i : Nat) (h : i as.size) (b : β) : m β := do
match i, h with
| 0, _ => pure b
@@ -326,17 +282,15 @@ protected def forIn' {α : Type u} {β : Type v} {m : Type v → Type w} [Monad
have h' : i < as.size := Nat.lt_of_lt_of_le (Nat.lt_succ_self i) h
have : as.size - 1 < as.size := Nat.sub_lt (Nat.zero_lt_of_lt h') (by decide)
have : as.size - 1 - i < as.size := Nat.lt_of_le_of_lt (Nat.sub_le (as.size - 1) i) this
match ( f as[as.size - 1 - i] (getElem_mem this) b) with
match ( f as[as.size - 1 - i] b) with
| ForInStep.done b => pure b
| ForInStep.yield b => loop i (Nat.le_of_lt h') b
loop as.size (Nat.le_refl _) b
instance : ForIn' m (Array α) α inferInstance where
forIn' := Array.forIn'
instance : ForIn m (Array α) α where
forIn := Array.forIn
-- No separate `ForIn` instance is required because it can be derived from `ForIn'`.
/-- See comment at `forIn'Unsafe` -/
/-- See comment at `forInUnsafe` -/
@[inline]
unsafe def foldlMUnsafe {α : Type u} {β : Type v} {m : Type v Type w} [Monad m] (f : β α m β) (init : β) (as : Array α) (start := 0) (stop := as.size) : m β :=
let rec @[specialize] fold (i : USize) (stop : USize) (b : β) : m β := do
@@ -371,7 +325,7 @@ def foldlM {α : Type u} {β : Type v} {m : Type v → Type w} [Monad m] (f : β
else
fold as.size (Nat.le_refl _)
/-- See comment at `forIn'Unsafe` -/
/-- See comment at `forInUnsafe` -/
@[inline]
unsafe def foldrMUnsafe {α : Type u} {β : Type v} {m : Type v Type w} [Monad m] (f : α β m β) (init : β) (as : Array α) (start := as.size) (stop := 0) : m β :=
let rec @[specialize] fold (i : USize) (stop : USize) (b : β) : m β := do
@@ -410,7 +364,7 @@ def foldrM {α : Type u} {β : Type v} {m : Type v → Type w} [Monad m] (f : α
else
pure init
/-- See comment at `forIn'Unsafe` -/
/-- See comment at `forInUnsafe` -/
@[inline]
unsafe def mapMUnsafe {α : Type u} {β : Type v} {m : Type v Type w} [Monad m] (f : α m β) (as : Array α) : m (Array β) :=
let sz := as.usize
@@ -441,25 +395,20 @@ def mapM {α : Type u} {β : Type v} {m : Type v → Type w} [Monad m] (f : α
decreasing_by simp_wf; decreasing_trivial_pre_omega
map 0 (mkEmpty as.size)
/-- Variant of `mapIdxM` which receives the index as a `Fin as.size`. -/
@[inline]
def mapFinIdxM {α : Type u} {β : Type v} {m : Type v Type w} [Monad m]
(as : Array α) (f : Fin as.size α m β) : m (Array β) :=
def mapIdxM {α : Type u} {β : Type v} {m : Type v Type w} [Monad m] (as : Array α) (f : Fin as.size α m β) : m (Array β) :=
let rec @[specialize] map (i : Nat) (j : Nat) (inv : i + j = as.size) (bs : Array β) : m (Array β) := do
match i, inv with
| 0, _ => pure bs
| i+1, inv =>
have j_lt : j < as.size := by
have : j < as.size := by
rw [ inv, Nat.add_assoc, Nat.add_comm 1 j, Nat.add_comm]
apply Nat.le_add_right
let idx : Fin as.size := j, this
have : i + (j + 1) = as.size := by rw [ inv, Nat.add_comm j 1, Nat.add_assoc]
map i (j+1) this (bs.push ( f j, j_lt (as.get j, j_lt)))
map i (j+1) this (bs.push ( f idx (as.get idx)))
map as.size 0 rfl (mkEmpty as.size)
@[inline]
def mapIdxM {α : Type u} {β : Type v} {m : Type v Type w} [Monad m] (as : Array α) (f : Nat α m β) : m (Array β) :=
as.mapFinIdxM fun i a => f i a
@[inline]
def findSomeM? {α : Type u} {β : Type v} {m : Type v Type w} [Monad m] (as : Array α) (f : α m (Option β)) : m (Option β) := do
for a in as do
@@ -565,13 +514,8 @@ def foldr {α : Type u} {β : Type v} (f : α → β → β) (init : β) (as : A
def map {α : Type u} {β : Type v} (f : α β) (as : Array α) : Array β :=
Id.run <| as.mapM f
/-- Variant of `mapIdx` which receives the index as a `Fin as.size`. -/
@[inline]
def mapFinIdx {α : Type u} {β : Type v} (as : Array α) (f : Fin as.size α β) : Array β :=
Id.run <| as.mapFinIdxM f
@[inline]
def mapIdx {α : Type u} {β : Type v} (as : Array α) (f : Nat α β) : Array β :=
def mapIdx {α : Type u} {β : Type v} (as : Array α) (f : Fin as.size α β) : Array β :=
Id.run <| as.mapIdxM f
/-- Turns `#[a, b]` into `#[(a, 0), (b, 1)]`. -/
@@ -662,22 +606,18 @@ protected def appendList (as : Array α) (bs : List α) : Array α :=
instance : HAppend (Array α) (List α) (Array α) := Array.appendList
@[inline]
def flatMapM [Monad m] (f : α m (Array β)) (as : Array α) : m (Array β) :=
def concatMapM [Monad m] (f : α m (Array β)) (as : Array α) : m (Array β) :=
as.foldlM (init := empty) fun bs a => do return bs ++ ( f a)
@[deprecated flatMapM (since := "2024-10-16")] abbrev concatMapM := @flatMapM
@[inline]
def flatMap (f : α Array β) (as : Array α) : Array β :=
def concatMap (f : α Array β) (as : Array α) : Array β :=
as.foldl (init := empty) fun bs a => bs ++ f a
@[deprecated flatMap (since := "2024-10-16")] abbrev concatMap := @flatMap
/-- Joins array of array into a single array.
`flatten #[#[a₁, a₂, ⋯], #[b₁, b₂, ⋯], ⋯]` = `#[a₁, a₂, ⋯, b₁, b₂, ⋯]`
-/
@[inline] def flatten (as : Array (Array α)) : Array α :=
def flatten (as : Array (Array α)) : Array α :=
as.foldl (init := empty) fun r a => r ++ a
@[inline]
@@ -780,7 +720,7 @@ 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_feraseIdx (a : Array α) (i : Fin a.size) : (a.feraseIdx i).size = a.size - 1 := by
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
@@ -870,33 +810,11 @@ def split (as : Array α) (p : α → Bool) : Array α × Array α :=
as.foldl (init := (#[], #[])) fun (as, bs) a =>
if p a then (as.push a, bs) else (as, bs.push a)
/-! ## Auxiliary functions used in metaprogramming.
/-! ### Auxiliary functions used in metaprogramming.
We do not currently intend to provide verification theorems for these functions.
We do not intend to provide verification theorems for these functions.
-/
/- ### reduceOption -/
/-- Drop `none`s from a Array, and replace each remaining `some a` with `a`. -/
@[inline] def reduceOption (as : Array (Option α)) : Array α :=
as.filterMap id
/-! ### eraseReps -/
/--
`O(|l|)`. Erase repeated adjacent elements. Keeps the first occurrence of each run.
* `eraseReps #[1, 3, 2, 2, 2, 3, 5] = #[1, 3, 2, 3, 5]`
-/
def eraseReps {α} [BEq α] (as : Array α) : Array α :=
if h : 0 < as.size then
let last, r := as.foldl (init := (as[0], #[])) fun last, r a =>
if a == last then last, r else a, r.push last
r.push last
else
#[]
/-! ### allDiff -/
private def allDiffAuxAux [BEq α] (as : Array α) (a : α) : forall (i : Nat), i < as.size Bool
| 0, _ => true
| i+1, h =>
@@ -914,8 +832,6 @@ decreasing_by simp_wf; decreasing_trivial_pre_omega
def allDiff [BEq α] (as : Array α) : Bool :=
allDiffAux as 0
/-! ### getEvenElems -/
@[inline] def getEvenElems (as : Array α) : Array α :=
(·.2) <| as.foldl (init := (true, Array.empty)) fun (even, r) a =>
if even then

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

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@@ -23,7 +23,7 @@ theorem foldlM_eq_foldlM_toList.aux [Monad m]
· cases Nat.not_le_of_gt _ (Nat.zero_add _ H)
· rename_i i; rw [Nat.succ_add] at H
simp [foldlM_eq_foldlM_toList.aux f arr i (j+1) H]
rw (occs := .pos [2]) [ List.getElem_cons_drop_succ_eq_drop _]
rw (config := {occs := .pos [2]}) [ List.get_drop_eq_drop _ _ _]
rfl
· rw [List.drop_of_length_le (Nat.ge_of_not_lt _)]; rfl
@@ -42,7 +42,7 @@ theorem foldrM_eq_reverse_foldlM_toList.aux [Monad m]
unfold foldrM.fold
match i with
| 0 => simp [List.foldlM, List.take]
| i+1 => rw [ List.take_concat_get _ _ h]; simp [ (aux f arr · i)]
| i+1 => rw [ List.take_concat_get _ _ h]; simp [ (aux f arr · i)]; rfl
theorem foldrM_eq_reverse_foldlM_toList [Monad m] (f : α β m β) (init : β) (arr : Array α) :
arr.foldrM f init = arr.toList.reverse.foldlM (fun x y => f y x) init := by
@@ -73,7 +73,7 @@ theorem foldr_eq_foldr_toList (f : α → β → β) (init : β) (arr : Array α
@[simp] theorem append_eq_append (arr arr' : Array α) : arr.append arr' = arr ++ arr' := rfl
@[simp] theorem toList_append (arr arr' : Array α) :
@[simp] theorem append_toList (arr arr' : Array α) :
(arr ++ arr').toList = arr.toList ++ arr'.toList := by
rw [ append_eq_append]; unfold Array.append
rw [foldl_eq_foldl_toList]
@@ -111,8 +111,8 @@ abbrev toList_eq := @toListImpl_eq
@[deprecated pop_toList (since := "2024-09-09")]
abbrev pop_data := @pop_toList
@[deprecated toList_append (since := "2024-09-09")]
abbrev append_data := @toList_append
@[deprecated append_toList (since := "2024-09-09")]
abbrev append_data := @append_toList
@[deprecated appendList_toList (since := "2024-09-09")]
abbrev appendList_data := @appendList_toList

View File

@@ -6,16 +6,14 @@ 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
namespace Array
theorem rel_of_isEqvAux
{r : α α Bool} {a b : Array α} (hsz : a.size = b.size) {i : Nat} (hi : i a.size)
(r : α α Bool) (a b : Array α) (hsz : a.size = b.size) (i : Nat) (hi : i a.size)
(heqv : Array.isEqvAux a b hsz r i hi)
{j : Nat} (hj : j < i) : r (a[j]'(Nat.lt_of_lt_of_le hj hi)) (b[j]'(Nat.lt_of_lt_of_le hj (hsz hi))) := by
(j : Nat) (hj : j < i) : r (a[j]'(Nat.lt_of_lt_of_le hj hi)) (b[j]'(Nat.lt_of_lt_of_le hj (hsz hi))) := by
induction i with
| zero => contradiction
| succ i ih =>
@@ -28,46 +26,15 @@ theorem rel_of_isEqvAux
subst hj'
exact heqv.left
theorem isEqvAux_of_rel {r : α α Bool} {a b : Array α} (hsz : a.size = b.size) {i : Nat} (hi : i a.size)
(w : j, (hj : j < i) r (a[j]'(Nat.lt_of_lt_of_le hj hi)) (b[j]'(Nat.lt_of_lt_of_le hj (hsz hi)))) : Array.isEqvAux a b hsz r i hi := by
induction i with
| zero => simp [Array.isEqvAux]
| succ i ih =>
simp only [isEqvAux, Bool.and_eq_true]
exact w i (Nat.lt_add_one i), ih _ fun j hj => w j (Nat.lt_add_right 1 hj)
theorem rel_of_isEqv {r : α α Bool} {a b : Array α} :
theorem rel_of_isEqv (r : α α Bool) (a b : Array α) :
Array.isEqv a b r h : a.size = b.size, (i : Nat) (h' : i < a.size), r (a[i]) (b[i]'(h h')) := by
simp only [isEqv]
split <;> rename_i h
· exact fun h' => h, fun i => rel_of_isEqvAux h (Nat.le_refl ..) h'
· exact fun h' => h, rel_of_isEqvAux r a b h a.size (Nat.le_refl ..) h'
· intro; contradiction
theorem isEqv_iff_rel (a b : Array α) (r) :
Array.isEqv a b r h : a.size = b.size, (i : Nat) (h' : i < a.size), r (a[i]) (b[i]'(h h')) :=
rel_of_isEqv, fun h, w => by
simp only [isEqv, h, reduceDIte]
exact isEqvAux_of_rel h (by simp [h]) w
theorem isEqv_eq_decide (a b : Array α) (r) :
Array.isEqv a b r =
if h : a.size = b.size then decide ( (i : Nat) (h' : i < a.size), r (a[i]) (b[i]'(h h'))) else false := by
by_cases h : Array.isEqv a b r
· simp only [h, Bool.true_eq]
simp only [isEqv_iff_rel] at h
obtain h, w := h
simp [h, w]
· let h' := h
simp only [Bool.not_eq_true] at h
simp only [h, Bool.false_eq, dite_eq_right_iff, decide_eq_false_iff_not, Classical.not_forall,
Bool.not_eq_true]
simpa [isEqv_iff_rel] using h'
@[simp] theorem isEqv_toList [BEq α] (a b : Array α) : (a.toList.isEqv b.toList r) = (a.isEqv b r) := by
simp [isEqv_eq_decide, List.isEqv_eq_decide]
theorem eq_of_isEqv [DecidableEq α] (a b : Array α) (h : Array.isEqv a b (fun x y => x = y)) : a = b := by
have h, h' := rel_of_isEqv h
have h, h' := rel_of_isEqv (fun x y => x = y) a b h
exact ext _ _ h (fun i lt _ => by simpa using h' i lt)
theorem isEqvAux_self (r : α α Bool) (hr : a, r a a) (a : Array α) (i : Nat) (h : i a.size) :
@@ -89,22 +56,4 @@ instance [DecidableEq α] : DecidableEq (Array α) :=
| true => isTrue (eq_of_isEqv a b h)
| false => isFalse fun h' => by subst h'; rw [isEqv_self] at h; contradiction
theorem beq_eq_decide [BEq α] (a b : Array α) :
(a == b) = if h : a.size = b.size then
decide ( (i : Nat) (h' : i < a.size), a[i] == b[i]'(h h')) else false := by
simp [BEq.beq, isEqv_eq_decide]
@[simp] theorem beq_toList [BEq α] (a b : Array α) : (a.toList == b.toList) = (a == b) := by
simp [beq_eq_decide, List.beq_eq_decide]
end Array
namespace List
@[simp] theorem isEqv_toArray [BEq α] (a b : List α) : (a.toArray.isEqv b.toArray r) = (a.isEqv b r) := by
simp [isEqv_eq_decide, Array.isEqv_eq_decide]
@[simp] theorem beq_toArray [BEq α] (a b : List α) : (a.toArray == b.toArray) = (a == b) := by
simp [beq_eq_decide, Array.beq_eq_decide]
end List

View File

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

File diff suppressed because it is too large Load Diff

View File

@@ -1,112 +0,0 @@
/-
Copyright (c) 2022 Mario Carneiro. All rights reserved.
Released under Apache 2.0 license as described in the file LICENSE.
Authors: Mario Carneiro, Kim Morrison
-/
prelude
import Init.Data.Array.Lemmas
import Init.Data.List.MapIdx
namespace Array
/-! ### mapFinIdx -/
-- This could also be proved from `SatisfiesM_mapIdxM` in Batteries.
theorem mapFinIdx_induction (as : Array α) (f : Fin as.size α β)
(motive : Nat Prop) (h0 : motive 0)
(p : Fin as.size β Prop)
(hs : i, motive i.1 p i (f i as[i]) motive (i + 1)) :
motive as.size eq : (Array.mapFinIdx as f).size = as.size,
i h, p i, h ((Array.mapFinIdx as f)[i]) := by
let rec go {bs i j h} (h₁ : j = bs.size) (h₂ : i h h', p i, h bs[i]) (hm : motive j) :
let arr : Array β := Array.mapFinIdxM.map (m := Id) as f i j h bs
motive as.size eq : arr.size = as.size, i h, p i, h arr[i] := by
induction i generalizing j bs with simp [mapFinIdxM.map]
| zero =>
have := (Nat.zero_add _).symm.trans h
exact this hm, h₁ this, fun _ _ => h₂ ..
| succ i ih =>
apply @ih (bs.push (f j, by omega as[j])) (j + 1) (by omega) (by simp; omega)
· intro i i_lt h'
rw [getElem_push]
split
· apply h₂
· simp only [size_push] at h'
obtain rfl : i = j := by omega
apply (hs i, by omega hm).1
· exact (hs j, by omega hm).2
simp [mapFinIdx, mapFinIdxM]; exact go rfl nofun h0
theorem mapFinIdx_spec (as : Array α) (f : Fin as.size α β)
(p : Fin as.size β Prop) (hs : i, p i (f i as[i])) :
eq : (Array.mapFinIdx as f).size = as.size,
i h, p i, h ((Array.mapFinIdx as f)[i]) :=
(mapFinIdx_induction _ _ (fun _ => True) trivial p fun _ _ => hs .., trivial).2
@[simp] theorem size_mapFinIdx (a : Array α) (f : Fin a.size α β) : (a.mapFinIdx f).size = a.size :=
(mapFinIdx_spec (p := fun _ _ => True) (hs := fun _ => trivial)).1
@[simp] theorem size_zipWithIndex (as : Array α) : as.zipWithIndex.size = as.size :=
Array.size_mapFinIdx _ _
@[simp] theorem getElem_mapFinIdx (a : Array α) (f : Fin a.size α β) (i : Nat)
(h : i < (mapFinIdx a f).size) :
(a.mapFinIdx f)[i] = f i, by simp_all (a[i]'(by simp_all)) :=
(mapFinIdx_spec _ _ (fun i b => b = f i a[i]) fun _ => rfl).2 i _
@[simp] theorem getElem?_mapFinIdx (a : Array α) (f : Fin a.size α β) (i : Nat) :
(a.mapFinIdx f)[i]? =
a[i]?.pbind fun b h => f i, (getElem?_eq_some_iff.1 h).1 b := by
simp only [getElem?_def, size_mapFinIdx, getElem_mapFinIdx]
split <;> simp_all
@[simp] theorem toList_mapFinIdx (a : Array α) (f : Fin a.size α β) :
(a.mapFinIdx f).toList = a.toList.mapFinIdx (fun i a => f i, by simp a) := by
apply List.ext_getElem <;> simp
/-! ### mapIdx -/
theorem mapIdx_induction (as : Array α) (f : Nat α β)
(motive : Nat Prop) (h0 : motive 0)
(p : Fin as.size β Prop)
(hs : i, motive i.1 p i (f i as[i]) motive (i + 1)) :
motive as.size eq : (Array.mapIdx as f).size = as.size,
i h, p i, h ((Array.mapIdx as f)[i]) :=
mapFinIdx_induction as (fun i a => f i a) motive h0 p hs
theorem mapIdx_spec (as : Array α) (f : Nat α β)
(p : Fin as.size β Prop) (hs : i, p i (f i as[i])) :
eq : (Array.mapIdx as f).size = as.size,
i h, p i, h ((Array.mapIdx as f)[i]) :=
(mapIdx_induction _ _ (fun _ => True) trivial p fun _ _ => hs .., trivial).2
@[simp] theorem size_mapIdx (a : Array α) (f : Nat α β) : (a.mapIdx f).size = a.size :=
(mapIdx_spec (p := fun _ _ => True) (hs := fun _ => trivial)).1
@[simp] theorem getElem_mapIdx (a : Array α) (f : Nat α β) (i : Nat)
(h : i < (mapIdx a f).size) :
(a.mapIdx f)[i] = f i (a[i]'(by simp_all)) :=
(mapIdx_spec _ _ (fun i b => b = f i a[i]) fun _ => rfl).2 i (by simp_all)
@[simp] theorem getElem?_mapIdx (a : Array α) (f : Nat α β) (i : Nat) :
(a.mapIdx f)[i]? =
a[i]?.map (f i) := by
simp [getElem?_def, size_mapIdx, getElem_mapIdx]
@[simp] theorem toList_mapIdx (a : Array α) (f : Nat α β) :
(a.mapIdx f).toList = a.toList.mapIdx (fun i a => f i a) := by
apply List.ext_getElem <;> simp
end Array
namespace List
@[simp] theorem mapFinIdx_toArray (l : List α) (f : Fin l.length α β) :
l.toArray.mapFinIdx f = (l.mapFinIdx f).toArray := by
ext <;> simp
@[simp] theorem mapIdx_toArray (l : List α) (f : Nat α β) :
l.toArray.mapIdx f = (l.mapIdx f).toArray := by
ext <;> simp
end List

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@@ -10,6 +10,15 @@ import Init.Data.List.BasicAux
namespace Array
/-- `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.
structure Mem (as : Array α) (a : α) : Prop where
val : a as.toList
instance : Membership α (Array α) where
mem := Mem
theorem sizeOf_lt_of_mem [SizeOf α] {as : Array α} (h : a as) : sizeOf a < sizeOf as := by
cases as with | _ as =>
exact Nat.lt_trans (List.sizeOf_lt_of_mem h.val) (by simp_arith)

View File

@@ -5,7 +5,6 @@ Authors: Leonardo de Moura
-/
prelude
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
@@ -45,11 +44,4 @@ def qpartition (as : Array α) (lt : αα → Bool) (lo hi : Nat) : Nat ×
else as
sort as low high
set_option linter.unusedVariables.funArgs false in
/--
Sort an array using `compare` to compare elements.
-/
def qsortOrd [ord : Ord α] (xs : Array α) : Array α :=
xs.qsort fun x y => compare x y |>.isLT
end Array

View File

@@ -59,22 +59,6 @@ def popFront (s : Subarray α) : Subarray α :=
else
s
/--
The empty subarray.
-/
protected def empty : Subarray α where
array := #[]
start := 0
stop := 0
start_le_stop := Nat.le_refl 0
stop_le_array_size := Nat.le_refl 0
instance : EmptyCollection (Subarray α) :=
Subarray.empty
instance : Inhabited (Subarray α) :=
{}
@[inline] unsafe def forInUnsafe {α : Type u} {β : Type v} {m : Type v Type w} [Monad m] (s : Subarray α) (b : β) (f : α β m (ForInStep β)) : m β :=
let sz := USize.ofNat s.stop
let rec @[specialize] loop (i : USize) (b : β) : m β := do

View File

@@ -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_eq_getElem_toList, uset, toList_set] using
simpa only [ugetElem_eq_getElem, getElem_eq_toList_getElem, uset, toList_set] using
List.exists_of_set _
end Array

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@@ -1,20 +1,19 @@
/-
Copyright (c) 2024 Lean FRO, LLC. All rights reserved.
Released under Apache 2.0 license as described in the file LICENSE.
Authors: Joe Hendrix, Wojciech Nawrocki, Leonardo de Moura, Mario Carneiro, Alex Keizer, Harun Khan, Abdalrhman M Mohamed, Siddharth Bhat
Authors: Joe Hendrix, Wojciech Nawrocki, Leonardo de Moura, Mario Carneiro, Alex Keizer, Harun Khan, Abdalrhman M Mohamed
-/
prelude
import Init.Data.Fin.Basic
import Init.Data.Nat.Bitwise.Lemmas
import Init.Data.Nat.Power2
import Init.Data.Int.Bitwise
import Init.Data.BitVec.BasicAux
/-!
We define the basic algebraic structure of bitvectors. We choose the `Fin` representation over
others for its relative efficiency (Lean has special support for `Nat`), and the fact that bitwise
operations on `Fin` are already defined. Some other possible representations are `List Bool`,
`{ l : List Bool // l.length = w }`, `Fin w → Bool`.
We define bitvectors. We choose the `Fin` representation over others for its relative efficiency
(Lean has special support for `Nat`), alignment with `UIntXY` types which are also represented
with `Fin`, and the fact that bitwise operations on `Fin` are already defined. Some other possible
representations are `List Bool`, `{ l : List Bool // l.length = w }`, `Fin w → Bool`.
We define many of the bitvector operations from the
[`QF_BV` logic](https://smtlib.cs.uiowa.edu/logics-all.shtml#QF_BV).
@@ -23,12 +22,60 @@ of SMT-LIBv2.
set_option linter.missingDocs true
/--
A bitvector of the specified width.
This is represented as the underlying `Nat` number in both the runtime
and the kernel, inheriting all the special support for `Nat`.
-/
structure BitVec (w : Nat) where
/-- Construct a `BitVec w` from a number less than `2^w`.
O(1), because we use `Fin` as the internal representation of a bitvector. -/
ofFin ::
/-- Interpret a bitvector as a number less than `2^w`.
O(1), because we use `Fin` as the internal representation of a bitvector. -/
toFin : Fin (2^w)
/--
Bitvectors have decidable equality. This should be used via the instance `DecidableEq (BitVec n)`.
-/
-- We manually derive the `DecidableEq` instances for `BitVec` because
-- we want to have builtin support for bit-vector literals, and we
-- need a name for this function to implement `canUnfoldAtMatcher` at `WHNF.lean`.
def BitVec.decEq (x y : BitVec n) : Decidable (x = y) :=
match x, y with
| n, m =>
if h : n = m then
isTrue (h rfl)
else
isFalse (fun h' => BitVec.noConfusion h' (fun h' => absurd h' h))
instance : DecidableEq (BitVec n) := BitVec.decEq
namespace BitVec
section Nat
/-- The `BitVec` with value `i`, given a proof that `i < 2^n`. -/
@[match_pattern]
protected def ofNatLt {n : Nat} (i : Nat) (p : i < 2^n) : BitVec n where
toFin := i, p
/-- The `BitVec` with value `i mod 2^n`. -/
@[match_pattern]
protected def ofNat (n : Nat) (i : Nat) : BitVec n where
toFin := Fin.ofNat' (2^n) i
instance instOfNat : OfNat (BitVec n) i where ofNat := .ofNat n i
instance natCastInst : NatCast (BitVec w) := BitVec.ofNat w
/-- Given a bitvector `x`, return the underlying `Nat`. This is O(1) because `BitVec` is a
(zero-cost) wrapper around a `Nat`. -/
protected def toNat (x : BitVec n) : Nat := x.toFin.val
/-- Return the bound in terms of toNat. -/
theorem isLt (x : BitVec w) : x.toNat < 2^w := x.toFin.isLt
@[deprecated isLt (since := "2024-03-12")]
theorem toNat_lt (x : BitVec n) : x.toNat < 2^n := x.isLt
@@ -191,6 +238,22 @@ end repr_toString
section arithmetic
/--
Addition for bit vectors. This can be interpreted as either signed or unsigned addition
modulo `2^n`.
SMT-Lib name: `bvadd`.
-/
protected def add (x y : BitVec n) : BitVec n := .ofNat n (x.toNat + y.toNat)
instance : Add (BitVec n) := BitVec.add
/--
Subtraction for bit vectors. This can be interpreted as either signed or unsigned subtraction
modulo `2^n`.
-/
protected def sub (x y : BitVec n) : BitVec n := .ofNat n ((2^n - y.toNat) + x.toNat)
instance : Sub (BitVec n) := BitVec.sub
/--
Negation for bit vectors. This can be interpreted as either signed or unsigned negation
modulo `2^n`.
@@ -206,8 +269,8 @@ Return the absolute value of a signed bitvector.
protected def abs (x : BitVec n) : BitVec n := if x.msb then .neg x else x
/--
Multiplication for bit vectors. This can be interpreted as either signed or unsigned
multiplication modulo `2^n`.
Multiplication for bit vectors. This can be interpreted as either signed or unsigned negation
modulo `2^n`.
SMT-Lib name: `bvmul`.
-/
@@ -324,6 +387,10 @@ SMT-Lib name: `bvult`.
-/
protected def ult (x y : BitVec n) : Bool := x.toNat < y.toNat
instance : LT (BitVec n) where lt := (·.toNat < ·.toNat)
instance (x y : BitVec n) : Decidable (x < y) :=
inferInstanceAs (Decidable (x.toNat < y.toNat))
/--
Unsigned less-than-or-equal-to for bit vectors.
@@ -331,6 +398,10 @@ SMT-Lib name: `bvule`.
-/
protected def ule (x y : BitVec n) : Bool := x.toNat y.toNat
instance : LE (BitVec n) where le := (·.toNat ·.toNat)
instance (x y : BitVec n) : Decidable (x y) :=
inferInstanceAs (Decidable (x.toNat y.toNat))
/--
Signed less-than for bit vectors.
@@ -605,13 +676,6 @@ result of appending a single bit to the front in the naive implementation).
That is, the new bit is the least significant bit. -/
def concat {n} (msbs : BitVec n) (lsb : Bool) : BitVec (n+1) := msbs ++ (ofBool lsb)
/--
`x.shiftConcat b` shifts all bits of `x` to the left by `1` and sets the least significant bit to `b`.
It is a non-dependent version of `concat` that does not change the total bitwidth.
-/
def shiftConcat (x : BitVec n) (b : Bool) : BitVec n :=
(x.concat b).truncate n
/-- Prepend a single bit to the front of a bitvector, using big endian order (see `append`).
That is, the new bit is the most significant bit. -/
def cons {n} (msb : Bool) (lsbs : BitVec n) : BitVec (n+1) :=
@@ -634,16 +698,6 @@ def twoPow (w : Nat) (i : Nat) : BitVec w := 1#w <<< i
end bitwise
/-- Compute a hash of a bitvector, combining 64-bit words using `mixHash`. -/
def hash (bv : BitVec n) : UInt64 :=
if n 64 then
bv.toFin.val.toUInt64
else
mixHash (bv.toFin.val.toUInt64) (hash ((bv >>> 64).setWidth (n - 64)))
instance : Hashable (BitVec n) where
hash := hash
section normalization_eqs
/-! We add simp-lemmas that rewrite bitvector operations into the equivalent notation -/
@[simp] theorem append_eq (x : BitVec w) (y : BitVec v) : BitVec.append x y = x ++ y := rfl
@@ -657,8 +711,6 @@ section normalization_eqs
@[simp] theorem add_eq (x y : BitVec w) : BitVec.add x y = x + y := rfl
@[simp] theorem sub_eq (x y : BitVec w) : BitVec.sub x y = x - y := rfl
@[simp] theorem mul_eq (x y : BitVec w) : BitVec.mul x y = x * y := rfl
@[simp] theorem udiv_eq (x y : BitVec w) : BitVec.udiv x y = x / y := rfl
@[simp] theorem umod_eq (x y : BitVec w) : BitVec.umod x y = x % y := rfl
@[simp] theorem zero_eq : BitVec.zero n = 0#n := rfl
end normalization_eqs

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@@ -1,52 +0,0 @@
/-
Copyright (c) 2024 Lean FRO, LLC. All rights reserved.
Released under Apache 2.0 license as described in the file LICENSE.
Authors: Joe Hendrix, Wojciech Nawrocki, Leonardo de Moura, Mario Carneiro, Alex Keizer, Harun Khan, Abdalrhman M Mohamed
-/
prelude
import Init.Data.Fin.Basic
set_option linter.missingDocs true
/-!
This module exists to provide the very basic `BitVec` definitions required for
`Init.Data.UInt.BasicAux`.
-/
namespace BitVec
section Nat
/-- The `BitVec` with value `i mod 2^n`. -/
@[match_pattern]
protected def ofNat (n : Nat) (i : Nat) : BitVec n where
toFin := Fin.ofNat' (2^n) i
instance instOfNat : OfNat (BitVec n) i where ofNat := .ofNat n i
/-- Return the bound in terms of toNat. -/
theorem isLt (x : BitVec w) : x.toNat < 2^w := x.toFin.isLt
end Nat
section arithmetic
/--
Addition for bit vectors. This can be interpreted as either signed or unsigned addition
modulo `2^n`.
SMT-Lib name: `bvadd`.
-/
protected def add (x y : BitVec n) : BitVec n := .ofNat n (x.toNat + y.toNat)
instance : Add (BitVec n) := BitVec.add
/--
Subtraction for bit vectors. This can be interpreted as either signed or unsigned subtraction
modulo `2^n`.
-/
protected def sub (x y : BitVec n) : BitVec n := .ofNat n ((2^n - y.toNat) + x.toNat)
instance : Sub (BitVec n) := BitVec.sub
end arithmetic
end BitVec

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@@ -1,7 +1,7 @@
/-
Copyright (c) 2024 Lean FRO, LLC. All rights reserved.
Released under Apache 2.0 license as described in the file LICENSE.
Authors: Harun Khan, Abdalrhman M Mohamed, Joe Hendrix, Siddharth Bhat
Authors: Harun Khan, Abdalrhman M Mohamed, Joe Hendrix
-/
prelude
import Init.Data.BitVec.Folds
@@ -18,80 +18,6 @@ as vectors of bits into proofs about Lean `BitVec` values.
The module is named for the bit-blasting operation in an SMT solver that converts bitvector
expressions into expressions about individual bits in each vector.
### Example: How bitblasting works for multiplication
We explain how the lemmas here are used for bitblasting,
by using multiplication as a prototypical example.
Other bitblasters for other operations follow the same pattern.
To bitblast a multiplication of the form `x * y`,
we must unfold the above into a form that the SAT solver understands.
We assume that the solver already knows how to bitblast addition.
This is known to `bv_decide`, by exploiting the lemma `add_eq_adc`,
which says that `x + y : BitVec w` equals `(adc x y false).2`,
where `adc` builds an add-carry circuit in terms of the primitive operations
(bitwise and, bitwise or, bitwise xor) that bv_decide already understands.
In this way, we layer bitblasters on top of each other,
by reducing the multiplication bitblaster to an addition operation.
The core lemma is given by `getLsbD_mul`:
```lean
x y : BitVec w ⊢ (x * y).getLsbD i = (mulRec x y w).getLsbD i
```
Which says that the `i`th bit of `x * y` can be obtained by
evaluating the `i`th bit of `(mulRec x y w)`.
Once again, we assume that `bv_decide` knows how to implement `getLsbD`,
given that `mulRec` can be understood by `bv_decide`.
We write two lemmas to enable `bv_decide` to unfold `(mulRec x y w)`
into a complete circuit, **when `w` is a known constant**`.
This is given by two recurrence lemmas, `mulRec_zero_eq` and `mulRec_succ_eq`,
which are applied repeatedly when the width is `0` and when the width is `w' + 1`:
```lean
mulRec_zero_eq :
mulRec x y 0 =
if y.getLsbD 0 then x else 0
mulRec_succ_eq
mulRec x y (s + 1) =
mulRec x y s +
if y.getLsbD (s + 1) then (x <<< (s + 1)) else 0 := rfl
```
By repeatedly applying the lemmas `mulRec_zero_eq` and `mulRec_succ_eq`,
one obtains a circuit for multiplication.
Note that this circuit uses `BitVec.add`, `BitVec.getLsbD`, `BitVec.shiftLeft`.
Here, `BitVec.add` and `BitVec.shiftLeft` are (recursively) bitblasted by `bv_decide`,
using the lemmas `add_eq_adc` and `shiftLeft_eq_shiftLeftRec`,
and `BitVec.getLsbD` is a primitive that `bv_decide` knows how to reduce to SAT.
The two lemmas, `mulRec_zero_eq`, and `mulRec_succ_eq`,
are used in `Std.Tactic.BVDecide.BVExpr.bitblast.blastMul`
to prove the correctness of the circuit that is built by `bv_decide`.
```lean
def blastMul (aig : AIG BVBit) (input : AIG.BinaryRefVec aig w) : AIG.RefVecEntry BVBit w
theorem denote_blastMul (aig : AIG BVBit) (lhs rhs : BitVec w) (assign : Assignment) :
...
⟦(blastMul aig input).aig, (blastMul aig input).vec.get idx hidx, assign.toAIGAssignment⟧
=
(lhs * rhs).getLsbD idx
```
The definition and theorem above are internal to `bv_decide`,
and use `mulRec_{zero,succ}_eq` to prove that the circuit built by `bv_decide`
computes the correct value for multiplication.
To zoom out, therefore, we follow two steps:
First, we prove bitvector lemmas to unfold a high-level operation (such as multiplication)
into already bitblastable operations (such as addition and left shift).
We then use these lemmas to prove the correctness of the circuit that `bv_decide` builds.
We use this workflow to implement bitblasting for all SMT-LIB2 operations.
## Main results
* `x + y : BitVec w` is `(adc x y false).2`.
@@ -174,30 +100,6 @@ theorem carry_succ (i : Nat) (x y : BitVec w) (c : Bool) :
exact mod_two_pow_add_mod_two_pow_add_bool_lt_two_pow_succ ..
cases x.toNat.testBit i <;> cases y.toNat.testBit i <;> (simp; omega)
theorem carry_succ_one (i : Nat) (x : BitVec w) (h : 0 < w) :
carry (i+1) x (1#w) false = decide ( j i, x.getLsbD j = true) := by
induction i with
| zero => simp [carry_succ, h]
| succ i ih =>
rw [carry_succ, ih]
simp only [getLsbD_one, add_one_ne_zero, decide_False, Bool.and_false, atLeastTwo_false_mid]
cases hx : x.getLsbD (i+1)
case false =>
have : j i + 1, x.getLsbD j = false :=
i+1, by omega, hx
simpa
case true =>
suffices
( (j : Nat), j i x.getLsbD j = true)
( (j : Nat), j i + 1 x.getLsbD j = true) by
simpa
constructor
· intro h j hj
rcases Nat.le_or_eq_of_le_succ hj with (hj' | rfl)
· apply h; assumption
· exact hx
· intro h j hj; apply h; omega
/--
If `x &&& y = 0`, then the carry bit `(x + y + 0)` is always `false` for any index `i`.
Intuitively, this is because a carry is only produced when at least two of `x`, `y`, and the
@@ -262,17 +164,6 @@ theorem getLsbD_add {i : Nat} (i_lt : i < w) (x y : BitVec w) :
(getLsbD x i ^^ (getLsbD y i ^^ carry i x y false)) := by
simpa using getLsbD_add_add_bool i_lt x y false
theorem getElem_add_add_bool {i : Nat} (i_lt : i < w) (x y : BitVec w) (c : Bool) :
(x + y + setWidth w (ofBool c))[i] =
(x[i] ^^ (y[i] ^^ carry i x y c)) := by
simp only [ getLsbD_eq_getElem]
rw [getLsbD_add_add_bool]
omega
theorem getElem_add {i : Nat} (i_lt : i < w) (x y : BitVec w) :
(x + y)[i] = (x[i] ^^ (y[i] ^^ carry i x y false)) := by
simpa using getElem_add_add_bool i_lt x y false
theorem adc_spec (x y : BitVec w) (c : Bool) :
adc x y c = (carry w x y c, x + y + setWidth w (ofBool c)) := by
simp only [adc]
@@ -291,21 +182,6 @@ theorem add_eq_adc (w : Nat) (x y : BitVec w) : x + y = (adc x y false).snd := b
/-! ### add -/
theorem getMsbD_add {i : Nat} {i_lt : i < w} {x y : BitVec w} :
getMsbD (x + y) i =
Bool.xor (getMsbD x i) (Bool.xor (getMsbD y i) (carry (w - 1 - i) x y false)) := by
simp [getMsbD, getLsbD_add, i_lt, show w - 1 - i < w by omega]
theorem msb_add {w : Nat} {x y: BitVec w} :
(x + y).msb =
Bool.xor x.msb (Bool.xor y.msb (carry (w - 1) x y false)) := by
simp only [BitVec.msb, BitVec.getMsbD]
by_cases h : w 0
· simp [h, show w = 0 by omega]
· rw [getLsbD_add (x := x)]
simp [show w > 0 by omega]
omega
/-- Adding a bitvector to its own complement yields the all ones bitpattern -/
@[simp] theorem add_not_self (x : BitVec w) : x + ~~~x = allOnes w := by
rw [add_eq_adc, adc, iunfoldr_replace (fun _ => false) (allOnes w)]
@@ -331,26 +207,6 @@ theorem add_eq_or_of_and_eq_zero {w : Nat} (x y : BitVec w)
simp_all [hx]
· by_cases hx : x.getLsbD i <;> simp_all [hx]
/-! ### Sub-/
theorem getLsbD_sub {i : Nat} {i_lt : i < w} {x y : BitVec w} :
(x - y).getLsbD i
= (x.getLsbD i ^^ ((~~~y + 1#w).getLsbD i ^^ carry i x (~~~y + 1#w) false)) := by
rw [sub_toAdd, BitVec.neg_eq_not_add, getLsbD_add]
omega
theorem getMsbD_sub {i : Nat} {i_lt : i < w} {x y : BitVec w} :
(x - y).getMsbD i =
(x.getMsbD i ^^ ((~~~y + 1).getMsbD i ^^ carry (w - 1 - i) x (~~~y + 1) false)) := by
rw [sub_toAdd, neg_eq_not_add, getMsbD_add]
· rfl
· omega
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
simp [sub_toAdd, BitVec.neg_eq_not_add, msb_add]
/-! ### Negation -/
theorem bit_not_testBit (x : BitVec w) (i : Fin w) :
@@ -376,117 +232,6 @@ theorem bit_neg_eq_neg (x : BitVec w) : -x = (adc (((iunfoldr (fun (i : Fin w) c
simp [ sub_toAdd, BitVec.sub_add_cancel]
· simp [bit_not_testBit x _]
/--
Remember that negating a bitvector is equal to incrementing the complement
by one, i.e., `-x = ~~~x + 1`. See also `neg_eq_not_add`.
This computation has two crucial properties:
- The least significant bit of `-x` is the same as the least significant bit of `x`, and
- The `i+1`-th least significant bit of `-x` is the complement of the `i+1`-th bit of `x`, unless
all of the preceding bits are `false`, in which case the bit is equal to the `i+1`-th bit of `x`
-/
theorem getLsbD_neg {i : Nat} {x : BitVec w} :
getLsbD (-x) i =
(getLsbD x i ^^ decide (i < w) && decide ( j < i, getLsbD x j = true)) := by
rw [neg_eq_not_add]
by_cases hi : i < w
· rw [getLsbD_add hi]
have : 0 < w := by omega
simp only [getLsbD_not, hi, decide_True, Bool.true_and, getLsbD_one, this, not_bne,
_root_.true_and, not_eq_eq_eq_not]
cases i with
| zero =>
have carry_zero : carry 0 ?x ?y false = false := by
simp [carry]; omega
simp [hi, carry_zero]
| succ =>
rw [carry_succ_one _ _ (by omega), Bool.xor_not, decide_not]
simp only [add_one_ne_zero, decide_False, getLsbD_not, and_eq_true, decide_eq_true_eq,
not_eq_eq_eq_not, Bool.not_true, false_bne, not_exists, _root_.not_and, not_eq_true,
bne_left_inj, decide_eq_decide]
constructor
· rintro h j hj; exact And.right <| h j (by omega)
· rintro h j hj; exact by omega, h j (by omega)
· have h_ge : w i := by omega
simp [getLsbD_ge _ _ h_ge, h_ge, hi]
theorem getMsbD_neg {i : Nat} {x : BitVec w} :
getMsbD (-x) i =
(getMsbD x i ^^ decide ( j < w, i < j getMsbD x j = true)) := by
simp only [getMsbD, getLsbD_neg, Bool.decide_and, Bool.and_eq_true, decide_eq_true_eq]
by_cases hi : i < w
case neg =>
simp [hi]; omega
case pos =>
have h₁ : w - 1 - i < w := by omega
simp only [hi, decide_True, h₁, Bool.true_and, Bool.bne_left_inj, decide_eq_decide]
constructor
· rintro j, hj, h
refine w - 1 - j, by omega, by omega, by omega, _root_.cast ?_ h
congr; omega
· rintro j, hj₁, hj₂, -, h
exact w - 1 - j, by omega, h
theorem msb_neg {w : Nat} {x : BitVec w} :
(-x).msb = ((x != 0#w && x != intMin w) ^^ x.msb) := by
simp only [BitVec.msb, getMsbD_neg]
by_cases hmin : x = intMin _
case pos =>
have : ( j, j < w 0 < j 0 < w j = 0) False := by
simp; omega
simp [hmin, getMsbD_intMin, this]
case neg =>
by_cases hzero : x = 0#w
case pos => simp [hzero]
case neg =>
have w_pos : 0 < w := by
cases w
· rw [@of_length_zero x] at hzero
contradiction
· omega
suffices j, j < w 0 < j x.getMsbD j = true
by simp [show x != 0#w by simpa, show x != intMin w by simpa, this]
false_or_by_contra
rename_i getMsbD_x
simp only [not_exists, _root_.not_and, not_eq_true] at getMsbD_x
/- `getMsbD` says that all bits except the msb are `false` -/
cases hmsb : x.msb
case true =>
apply hmin
apply eq_of_getMsbD_eq
rintro i, hi
simp only [getMsbD_intMin, w_pos, decide_True, Bool.true_and]
cases i
case zero => exact hmsb
case succ => exact getMsbD_x _ hi (by omega)
case false =>
apply hzero
apply eq_of_getMsbD_eq
rintro i, hi
simp only [getMsbD_zero]
cases i
case zero => exact hmsb
case succ => exact getMsbD_x _ hi (by omega)
/-! ### abs -/
theorem msb_abs {w : Nat} {x : BitVec w} :
x.abs.msb = (decide (x = intMin w) && decide (0 < w)) := by
simp only [BitVec.abs, getMsbD_neg, ne_eq, decide_not, Bool.not_bne]
by_cases h₀ : 0 < w
· by_cases h₁ : x = intMin w
· simp [h₁, msb_intMin]
· simp only [neg_eq, h₁, decide_False]
by_cases h₂ : x.msb
· simp [h₂, msb_neg]
and_intros
· by_cases h₃ : x = 0#w
· simp [h₃] at h₂
· simp [h₃]
· simp [h₁]
· simp [h₂]
· simp [BitVec.msb, show w = 0 by omega]
/-! ### Inequalities (le / lt) -/
theorem ult_eq_not_carry (x y : BitVec w) : x.ult y = !carry w x (~~~y) true := by
@@ -623,10 +368,6 @@ theorem getLsbD_mul (x y : BitVec w) (i : Nat) :
· simp
· omega
theorem getElem_mul {x y : BitVec w} {i : Nat} (h : i < w) :
(x * y)[i] = (mulRec x y w)[i] := by
simp [mulRec_eq_mul_signExtend_setWidth]
/-! ## shiftLeft recurrence for bitblasting -/
/--
@@ -697,385 +438,6 @@ theorem shiftLeft_eq_shiftLeftRec (x : BitVec w₁) (y : BitVec w₂) :
· simp [of_length_zero]
· simp [shiftLeftRec_eq]
/-! # udiv/urem recurrence for bitblasting
In order to prove the correctness of the division algorithm on the integers,
one shows that `n.div d = q` and `n.mod d = r` iff `n = d * q + r` and `0 ≤ r < d`.
Mnemonic: `n` is the numerator, `d` is the denominator, `q` is the quotient, and `r` the remainder.
This *uniqueness of decomposition* is not true for bitvectors.
For `n = 0, d = 3, w = 3`, we can write:
- `0 = 0 * 3 + 0` (`q = 0`, `r = 0 < 3`.)
- `0 = 2 * 3 + 2 = 6 + 2 ≃ 0 (mod 8)` (`q = 2`, `r = 2 < 3`).
Such examples can be created by choosing different `(q, r)` for a fixed `(d, n)`
such that `(d * q + r)` overflows and wraps around to equal `n`.
This tells us that the division algorithm must have more restrictions than just the ones
we have for integers. These restrictions are captured in `DivModState.Lawful`.
The key idea is to state the relationship in terms of the toNat values of {n, d, q, r}.
If the division equation `d.toNat * q.toNat + r.toNat = n.toNat` holds,
then `n.udiv d = q` and `n.umod d = r`.
Following this, we implement the division algorithm by repeated shift-subtract.
References:
- Fast 32-bit Division on the DSP56800E: Minimized nonrestoring division algorithm by David Baca
- Bitwuzla sources for bitblasting.h
-/
private theorem Nat.div_add_eq_left_of_lt {x y z : Nat} (hx : z x) (hy : y < z) (hz : 0 < z) :
(x + y) / z = x / z := by
refine Nat.div_eq_of_lt_le ?lo ?hi
· apply Nat.le_trans
· exact div_mul_le_self x z
· omega
· simp only [succ_eq_add_one, Nat.add_mul, Nat.one_mul]
apply Nat.add_lt_add_of_le_of_lt
· apply Nat.le_of_eq
exact (Nat.div_eq_iff_eq_mul_left hz hx).mp rfl
· exact hy
/-- If the division equation `d.toNat * q.toNat + r.toNat = n.toNat` holds,
then `n.udiv d = q`. -/
theorem udiv_eq_of_mul_add_toNat {d n q r : BitVec w} (hd : 0 < d)
(hrd : r < d)
(hdqnr : d.toNat * q.toNat + r.toNat = n.toNat) :
n / d = q := by
apply BitVec.eq_of_toNat_eq
rw [toNat_udiv]
replace hdqnr : (d.toNat * q.toNat + r.toNat) / d.toNat = n.toNat / d.toNat := by
simp [hdqnr]
rw [Nat.div_add_eq_left_of_lt] at hdqnr
· rw [ hdqnr]
exact mul_div_right q.toNat hd
· exact Nat.dvd_mul_right d.toNat q.toNat
· exact hrd
· exact hd
/-- If the division equation `d.toNat * q.toNat + r.toNat = n.toNat` holds,
then `n.umod d = r`. -/
theorem umod_eq_of_mul_add_toNat {d n q r : BitVec w} (hrd : r < d)
(hdqnr : d.toNat * q.toNat + r.toNat = n.toNat) :
n % d = r := by
apply BitVec.eq_of_toNat_eq
rw [toNat_umod]
replace hdqnr : (d.toNat * q.toNat + r.toNat) % d.toNat = n.toNat % d.toNat := by
simp [hdqnr]
rw [Nat.add_mod, Nat.mul_mod_right] at hdqnr
simp only [Nat.zero_add, mod_mod] at hdqnr
replace hrd : r.toNat < d.toNat := by
simpa [BitVec.lt_def] using hrd
rw [Nat.mod_eq_of_lt hrd] at hdqnr
simp [hdqnr]
/-! ### DivModState -/
/-- `DivModState` is a structure that maintains the state of recursive `divrem` calls. -/
structure DivModState (w : Nat) : Type where
/-- The number of bits in the numerator that are not yet processed -/
wn : Nat
/-- The number of bits in the remainder (and quotient) -/
wr : Nat
/-- The current quotient. -/
q : BitVec w
/-- The current remainder. -/
r : BitVec w
/-- `DivModArgs` contains the arguments to a `divrem` call which remain constant throughout
execution. -/
structure DivModArgs (w : Nat) where
/-- the numerator (aka, dividend) -/
n : BitVec w
/-- the denumerator (aka, divisor)-/
d : BitVec w
/-- A `DivModState` is lawful if the remainder width `wr` plus the numerator width `wn` equals `w`,
and the bitvectors `r` and `n` have values in the bounds given by bitwidths `wr`, resp. `wn`.
This is a proof engineering choice: an alternative world could have been
`r : BitVec wr` and `n : BitVec wn`, but this required much more dependent typing coercions.
Instead, we choose to declare all involved bitvectors as length `w`, and then prove that
the values are within their respective bounds.
We start with `wn = w` and `wr = 0`, and then in each step, we decrement `wn` and increment `wr`.
In this way, we grow a legal remainder in each loop iteration.
-/
structure DivModState.Lawful {w : Nat} (args : DivModArgs w) (qr : DivModState w) : Prop where
/-- The sum of widths of the dividend and remainder is `w`. -/
hwrn : qr.wr + qr.wn = w
/-- The denominator is positive. -/
hdPos : 0 < args.d
/-- The remainder is strictly less than the denominator. -/
hrLtDivisor : qr.r.toNat < args.d.toNat
/-- The remainder is morally a `Bitvec wr`, and so has value less than `2^wr`. -/
hrWidth : qr.r.toNat < 2^qr.wr
/-- The quotient is morally a `Bitvec wr`, and so has value less than `2^wr`. -/
hqWidth : qr.q.toNat < 2^qr.wr
/-- The low `(w - wn)` bits of `n` obey the invariant for division. -/
hdiv : args.n.toNat >>> qr.wn = args.d.toNat * qr.q.toNat + qr.r.toNat
/-- A lawful DivModState implies `w > 0`. -/
def DivModState.Lawful.hw {args : DivModArgs w} {qr : DivModState w}
{h : DivModState.Lawful args qr} : 0 < w := by
have hd := h.hdPos
rcases w with rfl | w
· have hcontra : args.d = 0#0 := by apply Subsingleton.elim
rw [hcontra] at hd
simp at hd
· omega
/-- An initial value with both `q, r = 0`. -/
def DivModState.init (w : Nat) : DivModState w := {
wn := w
wr := 0
q := 0#w
r := 0#w
}
/-- The initial state is lawful. -/
def DivModState.lawful_init {w : Nat} (args : DivModArgs w) (hd : 0#w < args.d) :
DivModState.Lawful args (DivModState.init w) := by
simp only [BitVec.DivModState.init]
exact {
hwrn := by simp only; omega,
hdPos := by assumption
hrLtDivisor := by simp [BitVec.lt_def] at hd ; assumption
hrWidth := by simp [DivModState.init],
hqWidth := by simp [DivModState.init],
hdiv := by
simp only [DivModState.init, toNat_ofNat, zero_mod, Nat.mul_zero, Nat.add_zero];
rw [Nat.shiftRight_eq_div_pow]
apply Nat.div_eq_of_lt args.n.isLt
}
/--
A lawful DivModState with a fully consumed dividend (`wn = 0`) witnesses that the
quotient has been correctly computed.
-/
theorem DivModState.udiv_eq_of_lawful {n d : BitVec w} {qr : DivModState w}
(h_lawful : DivModState.Lawful {n, d} qr)
(h_final : qr.wn = 0) :
n / d = qr.q := by
apply udiv_eq_of_mul_add_toNat h_lawful.hdPos h_lawful.hrLtDivisor
have hdiv := h_lawful.hdiv
simp only [h_final] at *
omega
/--
A lawful DivModState with a fully consumed dividend (`wn = 0`) witnesses that the
remainder has been correctly computed.
-/
theorem DivModState.umod_eq_of_lawful {qr : DivModState w}
(h : DivModState.Lawful {n, d} qr)
(h_final : qr.wn = 0) :
n % d = qr.r := by
apply umod_eq_of_mul_add_toNat h.hrLtDivisor
have hdiv := h.hdiv
simp only [shiftRight_zero] at hdiv
simp only [h_final] at *
exact hdiv.symm
/-! ### DivModState.Poised -/
/--
A `Poised` DivModState is a state which is `Lawful` and furthermore, has at least
one numerator bit left to process `(0 < wn)`
The input to the shift subtractor is a legal input to `divrem`, and we also need to have an
input bit to perform shift subtraction on, and thus we need `0 < wn`.
-/
structure DivModState.Poised {w : Nat} (args : DivModArgs w) (qr : DivModState w)
extends DivModState.Lawful args qr : Type where
/-- Only perform a round of shift-subtract if we have dividend bits. -/
hwn_lt : 0 < qr.wn
/--
In the shift subtract input, the dividend is at least one bit long (`wn > 0`), so
the remainder has bits to be computed (`wr < w`).
-/
def DivModState.wr_lt_w {qr : DivModState w} (h : qr.Poised args) : qr.wr < w := by
have hwrn := h.hwrn
have hwn_lt := h.hwn_lt
omega
/-! ### Division shift subtractor -/
/--
One round of the division algorithm, that tries to perform a subtract shift.
Note that this should only be called when `r.msb = false`, so we will not overflow.
-/
def divSubtractShift (args : DivModArgs w) (qr : DivModState w) : DivModState w :=
let {n, d} := args
let wn := qr.wn - 1
let wr := qr.wr + 1
let r' := shiftConcat qr.r (n.getLsbD wn)
if r' < d then {
q := qr.q.shiftConcat false, -- If `r' < d`, then we do not have a quotient bit.
r := r'
wn, wr
} else {
q := qr.q.shiftConcat true, -- Otherwise, `r' ≥ d`, and we have a quotient bit.
r := r' - d -- we subtract to maintain the invariant that `r < d`.
wn, wr
}
/-- The value of shifting right by `wn - 1` equals shifting by `wn` and grabbing the lsb at `(wn - 1)`. -/
theorem DivModState.toNat_shiftRight_sub_one_eq
{args : DivModArgs w} {qr : DivModState w} (h : qr.Poised args) :
args.n.toNat >>> (qr.wn - 1)
= (args.n.toNat >>> qr.wn) * 2 + (args.n.getLsbD (qr.wn - 1)).toNat := by
show BitVec.toNat (args.n >>> (qr.wn - 1)) = _
have {..} := h -- break the structure down for `omega`
rw [shiftRight_sub_one_eq_shiftConcat args.n h.hwn_lt]
rw [toNat_shiftConcat_eq_of_lt (k := w - qr.wn)]
· simp
· omega
· apply BitVec.toNat_ushiftRight_lt
omega
/--
This is used when proving the correctness of the division algorithm,
where we know that `r < d`.
We then want to show that `((r.shiftConcat b) - d) < d` as the loop invariant.
In arithmetic, this is the same as showing that
`r * 2 + 1 - d < d`, which this theorem establishes.
-/
private theorem two_mul_add_sub_lt_of_lt_of_lt_two (h : a < x) (hy : y < 2) :
2 * a + y - x < x := by omega
/-- We show that the output of `divSubtractShift` is lawful, which tells us that it
obeys the division equation. -/
theorem lawful_divSubtractShift (qr : DivModState w) (h : qr.Poised args) :
DivModState.Lawful args (divSubtractShift args qr) := by
rcases args with n, d
simp only [divSubtractShift, decide_eq_true_eq]
-- We add these hypotheses for `omega` to find them later.
have hrwn, hd, hrd, hr, hn, hrnd, hwn_lt := h
have : d.toNat * (qr.q.toNat * 2) = d.toNat * qr.q.toNat * 2 := by rw [Nat.mul_assoc]
by_cases rltd : shiftConcat qr.r (n.getLsbD (qr.wn - 1)) < d
· simp only [rltd, reduceIte]
constructor <;> try bv_omega
case pos.hrWidth => apply toNat_shiftConcat_lt_of_lt <;> omega
case pos.hqWidth => apply toNat_shiftConcat_lt_of_lt <;> omega
case pos.hdiv =>
simp [qr.toNat_shiftRight_sub_one_eq h, h.hdiv, this,
toNat_shiftConcat_eq_of_lt (qr.wr_lt_w h) h.hrWidth,
toNat_shiftConcat_eq_of_lt (qr.wr_lt_w h) h.hqWidth]
omega
· simp only [rltd, reduceIte]
constructor <;> try bv_omega
case neg.hrLtDivisor =>
simp only [lt_def, Nat.not_lt] at rltd
rw [BitVec.toNat_sub_of_le rltd,
toNat_shiftConcat_eq_of_lt (hk := qr.wr_lt_w h) (hx := h.hrWidth),
Nat.mul_comm]
apply two_mul_add_sub_lt_of_lt_of_lt_two <;> bv_omega
case neg.hrWidth =>
simp only
have hdr' : d (qr.r.shiftConcat (n.getLsbD (qr.wn - 1))) :=
BitVec.not_lt_iff_le.mp rltd
have hr' : ((qr.r.shiftConcat (n.getLsbD (qr.wn - 1)))).toNat < 2 ^ (qr.wr + 1) := by
apply toNat_shiftConcat_lt_of_lt <;> bv_omega
rw [BitVec.toNat_sub_of_le hdr']
omega
case neg.hqWidth =>
apply toNat_shiftConcat_lt_of_lt <;> omega
case neg.hdiv =>
have rltd' := (BitVec.not_lt_iff_le.mp rltd)
simp only [qr.toNat_shiftRight_sub_one_eq h,
BitVec.toNat_sub_of_le rltd',
toNat_shiftConcat_eq_of_lt (qr.wr_lt_w h) h.hrWidth]
simp only [BitVec.le_def,
toNat_shiftConcat_eq_of_lt (qr.wr_lt_w h) h.hrWidth] at rltd'
simp only [toNat_shiftConcat_eq_of_lt (qr.wr_lt_w h) h.hqWidth, h.hdiv, Nat.mul_add]
bv_omega
/-! ### Core division algorithm circuit -/
/-- A recursive definition of division for bitblasting, in terms of a shift-subtraction circuit. -/
def divRec {w : Nat} (m : Nat) (args : DivModArgs w) (qr : DivModState w) :
DivModState w :=
match m with
| 0 => qr
| m + 1 => divRec m args <| divSubtractShift args qr
@[simp]
theorem divRec_zero (qr : DivModState w) :
divRec 0 args qr = qr := rfl
@[simp]
theorem divRec_succ (m : Nat) (args : DivModArgs w) (qr : DivModState w) :
divRec (m + 1) args qr =
divRec m args (divSubtractShift args qr) := rfl
/-- The output of `divRec` is a lawful state -/
theorem lawful_divRec {args : DivModArgs w} {qr : DivModState w}
(h : DivModState.Lawful args qr) :
DivModState.Lawful args (divRec qr.wn args qr) := by
generalize hm : qr.wn = m
induction m generalizing qr
case zero =>
exact h
case succ wn' ih =>
simp only [divRec_succ]
apply ih
· apply lawful_divSubtractShift
constructor
· assumption
· omega
· simp only [divSubtractShift, hm]
split <;> rfl
/-- The output of `divRec` has no more bits left to process (i.e., `wn = 0`) -/
@[simp]
theorem wn_divRec (args : DivModArgs w) (qr : DivModState w) :
(divRec qr.wn args qr).wn = 0 := by
generalize hm : qr.wn = m
induction m generalizing qr
case zero =>
assumption
case succ wn' ih =>
apply ih
simp only [divSubtractShift, hm]
split <;> rfl
/-- The result of `udiv` agrees with the result of the division recurrence. -/
theorem udiv_eq_divRec (hd : 0#w < d) :
let out := divRec w {n, d} (DivModState.init w)
n / d = out.q := by
have := DivModState.lawful_init {n, d} hd
have := lawful_divRec this
apply DivModState.udiv_eq_of_lawful this (wn_divRec ..)
/-- The result of `umod` agrees with the result of the division recurrence. -/
theorem umod_eq_divRec (hd : 0#w < d) :
let out := divRec w {n, d} (DivModState.init w)
n % d = out.r := by
have := DivModState.lawful_init {n, d} hd
have := lawful_divRec this
apply DivModState.umod_eq_of_lawful this (wn_divRec ..)
theorem divRec_succ' (m : Nat) (args : DivModArgs w) (qr : DivModState w) :
divRec (m+1) args qr =
let wn := qr.wn - 1
let wr := qr.wr + 1
let r' := shiftConcat qr.r (args.n.getLsbD wn)
let input : DivModState _ :=
if r' < args.d then {
q := qr.q.shiftConcat false,
r := r'
wn, wr
} else {
q := qr.q.shiftConcat true,
r := r' - args.d
wn, wr
}
divRec m args input := by
simp [divRec_succ, divSubtractShift]
/- ### Arithmetic shift right (sshiftRight) recurrence -/
/--

File diff suppressed because it is too large Load Diff

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@@ -368,14 +368,13 @@ theorem and_or_inj_left_iff :
/-- convert a `Bool` to a `Nat`, `false -> 0`, `true -> 1` -/
def toNat (b : Bool) : Nat := cond b 1 0
@[simp, bv_toNat] theorem toNat_false : false.toNat = 0 := rfl
@[simp] theorem toNat_false : false.toNat = 0 := rfl
@[simp, bv_toNat] theorem toNat_true : true.toNat = 1 := rfl
@[simp] theorem toNat_true : true.toNat = 1 := rfl
theorem toNat_le (c : Bool) : c.toNat 1 := by
cases c <;> trivial
@[bv_toNat]
theorem toNat_lt (b : Bool) : b.toNat < 2 :=
Nat.lt_succ_of_le (toNat_le _)

View File

@@ -245,7 +245,7 @@ On an invalid position, returns `(default : UInt8)`. -/
@[inline]
def curr : Iterator UInt8
| arr, i =>
if h : i < arr.size then
if h:i < arr.size then
arr[i]'h
else
default

View File

@@ -4,7 +4,7 @@ Released under Apache 2.0 license as described in the file LICENSE.
Author: Leonardo de Moura
-/
prelude
import Init.Data.UInt.BasicAux
import Init.Data.UInt.Basic
/-- Determines if the given integer is a valid [Unicode scalar value](https://www.unicode.org/glossary/#unicode_scalar_value).
@@ -42,10 +42,8 @@ theorem isValidUInt32 (n : Nat) (h : isValidCharNat n) : n < UInt32.size := by
theorem isValidChar_of_isValidCharNat (n : Nat) (h : isValidCharNat n) : isValidChar (UInt32.ofNat' n (isValidUInt32 n h)) :=
match h with
| Or.inl h =>
Or.inl (UInt32.ofNat'_lt_of_lt _ (by decide) h)
| Or.inr h₁, h₂ =>
Or.inr UInt32.lt_ofNat'_of_lt _ (by decide) h₁, UInt32.ofNat'_lt_of_lt _ (by decide) h₂
| Or.inl h => Or.inl h
| Or.inr h₁, h₂ => Or.inr h₁, h
theorem isValidChar_zero : isValidChar 0 :=
Or.inl (by decide)
@@ -59,7 +57,7 @@ theorem isValidChar_zero : isValidChar 0 :=
c.val.toUInt8
/-- The numbers from 0 to 256 are all valid UTF-8 characters, so we can embed one in the other. -/
def ofUInt8 (n : UInt8) : Char := n.toUInt32, .inl (Nat.lt_trans n.toBitVec.isLt (by decide))
def ofUInt8 (n : UInt8) : Char := n.toUInt32, .inl (Nat.lt_trans n.1.2 (by decide))
instance : Inhabited Char where
default := 'A'

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

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@@ -244,13 +244,9 @@ theorem add_def (a b : Fin n) : a + b = Fin.mk ((a + b) % n) (Nat.mod_lt _ a.siz
theorem val_add (a b : Fin n) : (a + b).val = (a.val + b.val) % n := rfl
@[simp] protected theorem zero_add [NeZero n] (k : Fin n) : (0 : Fin n) + k = k := by
@[simp] protected theorem zero_add {n : Nat} [NeZero n] (i : Fin n) : (0 : Fin n) + i = i := by
ext
simp [Fin.add_def, Nat.mod_eq_of_lt k.2]
@[simp] protected theorem add_zero [NeZero n] (k : Fin n) : k + 0 = k := by
ext
simp [add_def, Nat.mod_eq_of_lt k.2]
simp [Fin.add_def, Nat.mod_eq_of_lt i.2]
theorem val_add_one_of_lt {n : Nat} {i : Fin n.succ} (h : i < last _) : (i + 1).1 = i + 1 := by
match n with
@@ -586,8 +582,8 @@ theorem rev_succ (k : Fin n) : rev (succ k) = castSucc (rev k) := k.rev_addNat 1
@[simp] theorem coe_pred (j : Fin (n + 1)) (h : j 0) : (j.pred h : Nat) = j - 1 := rfl
@[simp] theorem succ_pred : (i : Fin (n + 1)) (h : i 0), (i.pred h).succ = i
| 0, _, hi => by simp only [mk_zero, ne_eq, not_true] at hi
| _ + 1, _, _ => rfl
| 0, h, hi => by simp only [mk_zero, ne_eq, not_true] at hi
| n + 1, h, hi => rfl
@[simp]
theorem pred_succ (i : Fin n) {h : i.succ 0} : i.succ.pred h = i := by

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@@ -72,35 +72,21 @@ instance floatDecLt (a b : Float) : Decidable (a < b) := Float.decLt a b
instance floatDecLe (a b : Float) : Decidable (a b) := Float.decLe a b
@[extern "lean_float_to_string"] opaque Float.toString : Float 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`).
-/
/-- If the given float is positive, truncates the value to the nearest positive integer.
If negative or larger than the maximum value for UInt8, returns 0. -/
@[extern "lean_float_to_uint8"] opaque Float.toUInt8 : Float 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`).
-/
/-- If the given float is positive, truncates the value to the nearest positive integer.
If negative or larger than the maximum value for UInt16, returns 0. -/
@[extern "lean_float_to_uint16"] opaque Float.toUInt16 : Float 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`).
-/
/-- If the given float is positive, truncates the value to the nearest positive integer.
If negative or larger than the maximum value for UInt32, returns 0. -/
@[extern "lean_float_to_uint32"] opaque Float.toUInt32 : Float 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`).
-/
/-- If the given float is positive, truncates the value to the nearest positive integer.
If negative or larger than the maximum value for UInt64, returns 0. -/
@[extern "lean_float_to_uint64"] opaque Float.toUInt64 : Float 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).
-/
/-- If the given float is positive, truncates the value to the nearest positive integer.
If negative or larger than the maximum value for USize, returns 0. -/
@[extern "lean_float_to_usize"] opaque Float.toUSize : Float USize
@[extern "lean_float_isnan"] opaque Float.isNaN : Float Bool

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@@ -1,35 +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.Core
namespace Function
@[inline]
def curry : (α × β φ) α β φ := fun f a b => f (a, b)
/-- Interpret a function with two arguments as a function on `α × β` -/
@[inline]
def uncurry : (α β φ) α × β φ := fun f a => f a.1 a.2
@[simp]
theorem curry_uncurry (f : α β φ) : curry (uncurry f) = f :=
rfl
@[simp]
theorem uncurry_curry (f : α × β φ) : uncurry (curry f) = f :=
funext fun _a, _b => rfl
@[simp]
theorem uncurry_apply_pair {α β γ} (f : α β γ) (x : α) (y : β) : uncurry f (x, y) = f x y :=
rfl
@[simp]
theorem curry_apply {α β γ} (f : α × β γ) (x : α) (y : β) : curry f x y = f (x, y) :=
rfl
end Function

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@@ -48,15 +48,9 @@ instance : Hashable UInt64 where
instance : Hashable USize where
hash n := n.toUInt64
instance : Hashable ByteArray where
hash as := as.foldl (fun r a => mixHash r (hash a)) 7
instance : Hashable (Fin n) where
hash v := v.val.toUInt64
instance : Hashable Char where
hash c := c.val.toUInt64
instance : Hashable Int where
hash
| Int.ofNat n => UInt64.ofNat (2 * n)

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@@ -253,7 +253,7 @@ theorem tmod_def (a b : Int) : tmod a b = a - b * a.tdiv b := by
theorem fmod_add_fdiv : a b : Int, a.fmod b + b * a.fdiv b = a
| 0, ofNat _ | 0, -[_+1] => congrArg ofNat <| by simp
| succ _, ofNat _ => congrArg ofNat <| Nat.mod_add_div ..
| succ m, ofNat n => congrArg ofNat <| Nat.mod_add_div ..
| succ m, -[n+1] => by
show subNatNat (m % succ n) n + ((succ n * (m / succ n)) + n + 1) = (m + 1)
rw [Int.add_comm _ n, Int.add_assoc, Int.add_assoc,
@@ -289,8 +289,8 @@ theorem fmod_eq_tmod {a b : Int} (Ha : 0 ≤ a) (Hb : 0 ≤ b) : fmod a b = tmod
@[simp] protected theorem ediv_neg : a b : Int, a / (-b) = -(a / b)
| ofNat m, 0 => show ofNat (m / 0) = -(m / 0) by rw [Nat.div_zero]; rfl
| ofNat _, -[_+1] => (Int.neg_neg _).symm
| ofNat _, succ _ | -[_+1], 0 | -[_+1], succ _ | -[_+1], -[_+1] => rfl
| ofNat m, -[n+1] => (Int.neg_neg _).symm
| ofNat m, succ n | -[m+1], 0 | -[m+1], succ n | -[m+1], -[n+1] => rfl
theorem ediv_neg' {a b : Int} (Ha : a < 0) (Hb : 0 < b) : a / b < 0 :=
match a, b, eq_negSucc_of_lt_zero Ha, eq_succ_of_zero_lt Hb with
@@ -339,7 +339,7 @@ theorem add_mul_ediv_right (a b : Int) {c : Int} (H : c ≠ 0) : (a + b * c) / c
| _, k, rfl, -[n+1] => show (a - n.succ * k.succ).ediv k.succ = a.ediv k.succ - n.succ by
rw [ Int.add_sub_cancel (ediv ..), this, Int.sub_add_cancel]
fun {k n} => @fun
| ofNat _ => congrArg ofNat <| Nat.add_mul_div_right _ _ k.succ_pos
| ofNat m => congrArg ofNat <| Nat.add_mul_div_right _ _ k.succ_pos
| -[m+1] => by
show ((n * k.succ : Nat) - m.succ : Int).ediv k.succ = n - (m / k.succ + 1 : Nat)
by_cases h : m < n * k.succ
@@ -396,7 +396,7 @@ theorem add_mul_ediv_left (a : Int) {b : Int}
rw [Int.mul_neg, Int.ediv_neg, Int.ediv_neg]; apply congrArg Neg.neg; apply this
fun m k b =>
match b, k with
| ofNat _, _ => congrArg ofNat (Nat.mul_div_mul_left _ _ m.succ_pos)
| ofNat n, k => congrArg ofNat (Nat.mul_div_mul_left _ _ m.succ_pos)
| -[n+1], 0 => by
rw [Int.ofNat_zero, Int.mul_zero, Int.ediv_zero, Int.ediv_zero]
| -[n+1], succ k => congrArg negSucc <|
@@ -822,14 +822,14 @@ theorem ediv_eq_ediv_of_mul_eq_mul {a b c d : Int}
unseal Nat.div in
@[simp] protected theorem tdiv_neg : a b : Int, a.tdiv (-b) = -(a.tdiv b)
| ofNat m, 0 => show ofNat (m / 0) = -(m / 0) by rw [Nat.div_zero]; rfl
| ofNat _, -[_+1] | -[_+1], succ _ => (Int.neg_neg _).symm
| ofNat _, succ _ | -[_+1], 0 | -[_+1], -[_+1] => rfl
| ofNat m, -[n+1] | -[m+1], succ n => (Int.neg_neg _).symm
| ofNat m, succ n | -[m+1], 0 | -[m+1], -[n+1] => rfl
unseal Nat.div in
@[simp] protected theorem neg_tdiv : a b : Int, (-a).tdiv b = -(a.tdiv b)
| 0, n => by simp [Int.neg_zero]
| succ _, (n:Nat) | -[_+1], 0 | -[_+1], -[_+1] => rfl
| succ _, -[_+1] | -[_+1], succ _ => (Int.neg_neg _).symm
| succ m, (n:Nat) | -[m+1], 0 | -[m+1], -[n+1] => rfl
| succ m, -[n+1] | -[m+1], succ n => (Int.neg_neg _).symm
protected theorem neg_tdiv_neg (a b : Int) : (-a).tdiv (-b) = a.tdiv b := by
simp [Int.tdiv_neg, Int.neg_tdiv, Int.neg_neg]
@@ -1125,17 +1125,6 @@ theorem emod_add_bmod_congr (x : Int) (n : Nat) : Int.bmod (x%n + y) n = Int.bmo
simp [Int.emod_def, Int.sub_eq_add_neg]
rw [Int.mul_neg, Int.add_right_comm, Int.bmod_add_mul_cancel]
@[simp]
theorem emod_sub_bmod_congr (x : Int) (n : Nat) : Int.bmod (x%n - y) n = Int.bmod (x - y) n := by
simp only [emod_def, Int.sub_eq_add_neg]
rw [Int.mul_neg, Int.add_right_comm, Int.bmod_add_mul_cancel]
@[simp]
theorem sub_emod_bmod_congr (x : Int) (n : Nat) : Int.bmod (x - y%n) n = Int.bmod (x - y) n := by
simp only [emod_def]
rw [Int.sub_eq_add_neg, Int.neg_sub, Int.sub_eq_add_neg, Int.add_assoc, Int.add_right_comm,
Int.bmod_add_mul_cancel, Int.sub_eq_add_neg]
@[simp]
theorem emod_mul_bmod_congr (x : Int) (n : Nat) : Int.bmod (x%n * y) n = Int.bmod (x * y) n := by
simp [Int.emod_def, Int.sub_eq_add_neg]
@@ -1151,28 +1140,9 @@ theorem bmod_add_bmod_congr : Int.bmod (Int.bmod x n + y) n = Int.bmod (x + y) n
rw [Int.sub_eq_add_neg, Int.add_right_comm, Int.sub_eq_add_neg]
simp
@[simp]
theorem bmod_sub_bmod_congr : Int.bmod (Int.bmod x n - y) n = Int.bmod (x - y) n := by
rw [Int.bmod_def x n]
split
next p =>
simp only [emod_sub_bmod_congr]
next p =>
rw [Int.sub_eq_add_neg, Int.sub_eq_add_neg, Int.add_right_comm, Int.sub_eq_add_neg, Int.sub_eq_add_neg]
simp [emod_sub_bmod_congr]
@[simp] theorem add_bmod_bmod : Int.bmod (x + Int.bmod y n) n = Int.bmod (x + y) n := by
rw [Int.add_comm x, Int.bmod_add_bmod_congr, Int.add_comm y]
@[simp] theorem sub_bmod_bmod : Int.bmod (x - Int.bmod y n) n = Int.bmod (x - y) n := by
rw [Int.bmod_def y n]
split
next p =>
simp [sub_emod_bmod_congr]
next p =>
rw [Int.sub_eq_add_neg, Int.sub_eq_add_neg, Int.neg_add, Int.neg_neg, Int.add_assoc, Int.sub_eq_add_neg]
simp [sub_emod_bmod_congr]
@[simp]
theorem bmod_mul_bmod : Int.bmod (Int.bmod x n * y) n = Int.bmod (x * y) n := by
rw [bmod_def x n]
@@ -1267,7 +1237,7 @@ theorem bmod_le {x : Int} {m : Nat} (h : 0 < m) : bmod x m ≤ (m - 1) / 2 := by
_ = ((m + 1 - 2) + 2)/2 := by simp
_ = (m - 1) / 2 + 1 := by
rw [add_ediv_of_dvd_right]
· simp +decide only [Int.ediv_self]
· simp (config := {decide := true}) only [Int.ediv_self]
congr 2
rw [Int.add_sub_assoc, Int.sub_neg]
congr
@@ -1285,7 +1255,7 @@ theorem bmod_natAbs_plus_one (x : Int) (w : 1 < x.natAbs) : bmod x (x.natAbs + 1
simp only [bmod, ofNat_eq_coe, natAbs_ofNat, natCast_add, ofNat_one,
emod_self_add_one (ofNat_nonneg x)]
match x with
| 0 => rw [if_pos] <;> simp +decide
| 0 => rw [if_pos] <;> simp (config := {decide := true})
| (x+1) =>
rw [if_neg]
· simp [ Int.sub_sub]

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@@ -181,12 +181,12 @@ theorem subNatNat_add_negSucc (m n k : Nat) :
Nat.add_comm]
protected theorem add_assoc : a b c : Int, a + b + c = a + (b + c)
| (m:Nat), (n:Nat), _ => aux1 ..
| (m:Nat), (n:Nat), c => aux1 ..
| Nat.cast m, b, Nat.cast k => by
rw [Int.add_comm, aux1, Int.add_comm k, aux1, Int.add_comm b]
| a, (n:Nat), (k:Nat) => by
rw [Int.add_comm, Int.add_comm a, aux1, Int.add_comm a, Int.add_comm k]
| -[_+1], -[_+1], (k:Nat) => aux2 ..
| -[m+1], -[n+1], (k:Nat) => aux2 ..
| -[m+1], (n:Nat), -[k+1] => by
rw [Int.add_comm, aux2, Int.add_comm n, aux2, Int.add_comm -[m+1]]
| (m:Nat), -[n+1], -[k+1] => by

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@@ -512,8 +512,8 @@ theorem toNat_add_nat {a : Int} (ha : 0 ≤ a) (n : Nat) : (a + n).toNat = a.toN
@[simp] theorem pred_toNat : i : Int, (i - 1).toNat = i.toNat - 1
| 0 => rfl
| (_+1:Nat) => by simp [ofNat_add]
| -[_+1] => rfl
| (n+1:Nat) => by simp [ofNat_add]
| -[n+1] => rfl
theorem toNat_sub_toNat_neg : n : Int, n.toNat - (-n).toNat = n
| 0 => rfl
@@ -1007,9 +1007,9 @@ theorem sign_eq_neg_one_iff_neg {a : Int} : sign a = -1 ↔ a < 0 :=
match x with
| 0 => rfl
| .ofNat (_ + 1) =>
simp +decide only [sign, true_iff]
simp (config := { decide := true }) only [sign, true_iff]
exact Int.le_add_one (ofNat_nonneg _)
| .negSucc _ => simp +decide [sign]
| .negSucc _ => simp (config := { decide := true }) [sign]
theorem mul_sign : i : Int, i * sign i = natAbs i
| succ _ => Int.mul_one _

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@@ -5,7 +5,6 @@ Authors: Jeremy Avigad, Deniz Aydin, Floris van Doorn, Mario Carneiro
-/
prelude
import Init.Data.Int.Lemmas
import Init.Data.Nat.Lemmas
namespace Int
@@ -36,24 +35,10 @@ theorem pow_le_pow_of_le_right {n : Nat} (hx : n > 0) {i : Nat} : ∀ {j}, i ≤
theorem pos_pow_of_pos {n : Nat} (m : Nat) (h : 0 < n) : 0 < n^m :=
pow_le_pow_of_le_right h (Nat.zero_le _)
@[norm_cast]
theorem natCast_pow (b n : Nat) : ((b^n : Nat) : Int) = (b : Int) ^ n := by
match n with
| 0 => rfl
| n + 1 =>
simp only [Nat.pow_succ, Int.pow_succ, natCast_mul, natCast_pow _ n]
@[simp]
protected theorem two_pow_pred_sub_two_pow {w : Nat} (h : 0 < w) :
((2 ^ (w - 1) : Nat) - (2 ^ w : Nat) : Int) = - ((2 ^ (w - 1) : Nat) : Int) := by
rw [ Nat.two_pow_pred_add_two_pow_pred h]
omega
@[simp]
protected theorem two_pow_pred_sub_two_pow' {w : Nat} (h : 0 < w) :
(2 : Int) ^ (w - 1) - (2 : Int) ^ w = - (2 : Int) ^ (w - 1) := by
norm_cast
rw [ Nat.two_pow_pred_add_two_pow_pred h]
simp [h]
end Int

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@@ -23,6 +23,3 @@ import Init.Data.List.TakeDrop
import Init.Data.List.Zip
import Init.Data.List.Perm
import Init.Data.List.Sort
import Init.Data.List.ToArray
import Init.Data.List.MapIdx
import Init.Data.List.OfFn

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@@ -73,7 +73,7 @@ theorem map_pmap {p : α → Prop} (g : β → γ) (f : ∀ a, p a → β) (l H)
· simp only [*, pmap, map]
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
pmap g (map f l) H = pmap (fun a h => g (f a) h) l fun a h => H _ (mem_map_of_mem _ h) := by
induction l
· rfl
· simp only [*, pmap, map]
@@ -84,7 +84,7 @@ theorem attach_congr {l₁ l₂ : List α} (h : l₁ = l₂) :
simp
theorem attachWith_congr {l₁ l₂ : List 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
l₁.attachWith P H = l₂.attachWith P fun x h => H _ (w h) := by
subst w
simp
@@ -169,13 +169,6 @@ theorem pmap_ne_nil_iff {P : α → Prop} (f : (a : α) → P a → β) {xs : Li
(H : (a : α), a xs P a) : xs.pmap f H [] xs [] := by
simp
theorem pmap_eq_self {l : List α} {p : α Prop} (hp : (a : α), a l p a)
(f : (a : α) p a α) : l.pmap f hp = l a (h : a l), f a (hp a h) = a := by
rw [pmap_eq_map_attach]
conv => lhs; rhs; rw [ attach_map_subtype_val l]
rw [map_inj_left]
simp
@[simp]
theorem attach_eq_nil_iff {l : List α} : l.attach = [] l = [] :=
pmap_eq_nil_iff
@@ -360,7 +353,7 @@ theorem attach_map {l : List α} (f : α → β) :
induction l <;> simp [*]
theorem attachWith_map {l : List 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
(l.map f).attachWith P H = (l.attachWith (P f) (fun a h => H _ (mem_map_of_mem f h))).map
fun x, h => f x, h := by
induction l <;> simp [*]
@@ -555,135 +548,4 @@ theorem count_attachWith [DecidableEq α] {p : α → Prop} (l : List α) (H :
(l.attachWith p H).count a = l.count a :=
Eq.trans (countP_congr fun _ _ => by simp [Subtype.ext_iff]) <| countP_attachWith _ _ _
/-! ## unattach
`List.unattach` is the (one-sided) inverse of `List.attach`. It is a synonym for `List.map Subtype.val`.
We use it by providing a simp lemma `l.attach.unattach = l`, and simp lemmas which recognize higher order
functions applied to `l : List { x // p x }` which only depend on the value, not the predicate, and rewrite these
in terms of a simpler function applied to `l.unattach`.
Further, we provide simp lemmas that push `unattach` inwards.
-/
/--
A synonym for `l.map (·.val)`. Mostly this should not be needed by users.
It is introduced as an intermediate step by lemmas such as `map_subtype`,
and is ideally subsequently simplified away by `unattach_attach`.
If not, usually the right approach is `simp [List.unattach, -List.map_subtype]` to unfold.
-/
def unattach {α : Type _} {p : α Prop} (l : List { x // p x }) := l.map (·.val)
@[simp] theorem unattach_nil {p : α Prop} : ([] : List { x // p x }).unattach = [] := rfl
@[simp] theorem unattach_cons {p : α Prop} {a : { x // p x }} {l : List { x // p x }} :
(a :: l).unattach = a.val :: l.unattach := rfl
@[simp] theorem length_unattach {p : α Prop} {l : List { x // p x }} :
l.unattach.length = l.length := by
unfold unattach
simp
@[simp] theorem unattach_attach {l : List α} : l.attach.unattach = l := by
unfold unattach
induction l with
| nil => simp
| cons a l ih => simp [ih, Function.comp_def]
@[simp] theorem unattach_attachWith {p : α Prop} {l : List α}
{H : a l, p a} :
(l.attachWith p H).unattach = l := by
unfold unattach
induction l with
| nil => simp
| cons a l ih => simp [ih, Function.comp_def]
/-! ### Recognizing higher order functions on subtypes using a function that only depends on the value. -/
/--
This lemma identifies folds over lists of subtypes, where the function only depends on the value, not the proposition,
and simplifies these to the function directly taking the value.
-/
@[simp] theorem foldl_subtype {p : α Prop} {l : List { x // p x }}
{f : β { x // p x } β} {g : β α β} {x : β}
{hf : b x h, f b x, h = g b x} :
l.foldl f x = l.unattach.foldl g x := by
unfold unattach
induction l generalizing x with
| nil => simp
| cons a l ih => simp [ih, hf]
/--
This lemma identifies folds over lists of subtypes, where the function only depends on the value, not the proposition,
and simplifies these to the function directly taking the value.
-/
@[simp] theorem foldr_subtype {p : α Prop} {l : List { x // p x }}
{f : { x // p x } β β} {g : α β β} {x : β}
{hf : x h b, f x, h b = g x b} :
l.foldr f x = l.unattach.foldr g x := by
unfold unattach
induction l generalizing x with
| nil => simp
| cons a l ih => simp [ih, hf]
/--
This lemma identifies maps over lists of subtypes, where the function only depends on the value, not the proposition,
and simplifies these to the function directly taking the value.
-/
@[simp] theorem map_subtype {p : α Prop} {l : List { x // p x }}
{f : { x // p x } β} {g : α β} {hf : x h, f x, h = g x} :
l.map f = l.unattach.map g := by
unfold unattach
induction l with
| nil => simp
| cons a l ih => simp [ih, hf]
@[simp] theorem filterMap_subtype {p : α Prop} {l : List { x // p x }}
{f : { x // p x } Option β} {g : α Option β} {hf : x h, f x, h = g x} :
l.filterMap f = l.unattach.filterMap g := by
unfold unattach
induction l with
| nil => simp
| cons a l ih => simp [ih, hf, filterMap_cons]
@[simp] theorem flatMap_subtype {p : α Prop} {l : List { x // p x }}
{f : { x // p x } List β} {g : α List β} {hf : x h, f x, h = g x} :
(l.flatMap f) = l.unattach.flatMap g := by
unfold unattach
induction l with
| nil => simp
| cons a l ih => simp [ih, hf]
@[deprecated flatMap_subtype (since := "2024-10-16")] abbrev bind_subtype := @flatMap_subtype
@[simp] theorem unattach_filter {p : α Prop} {l : List { x // p x }}
{f : { x // p x } Bool} {g : α Bool} {hf : x h, f x, h = g x} :
(l.filter f).unattach = l.unattach.filter g := by
induction l with
| nil => simp
| cons a l ih =>
simp only [filter_cons, hf, unattach_cons]
split <;> simp [ih]
/-! ### Simp lemmas pushing `unattach` inwards. -/
@[simp] theorem unattach_reverse {p : α Prop} {l : List { x // p x }} :
l.reverse.unattach = l.unattach.reverse := by
simp [unattach, -map_subtype]
@[simp] theorem unattach_append {p : α Prop} {l₁ l₂ : List { x // p x }} :
(l₁ ++ l₂).unattach = l₁.unattach ++ l₂.unattach := by
simp [unattach, -map_subtype]
@[simp] theorem unattach_flatten {p : α Prop} {l : List (List { x // p x })} :
l.flatten.unattach = (l.map unattach).flatten := by
unfold unattach
induction l <;> simp_all
@[deprecated unattach_flatten (since := "2024-10-14")] abbrev unattach_join := @unattach_flatten
@[simp] theorem unattach_replicate {p : α Prop} {n : Nat} {x : { x // p x }} :
(List.replicate n x).unattach = List.replicate n x.1 := by
simp [unattach, -map_subtype]
end List

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@@ -29,23 +29,22 @@ The operations are organized as follow:
* Lexicographic ordering: `lt`, `le`, and instances.
* Head and tail operators: `head`, `head?`, `headD?`, `tail`, `tail?`, `tailD`.
* Basic operations:
`map`, `filter`, `filterMap`, `foldr`, `append`, `flatten`, `pure`, `flatMap`, `replicate`, and
`map`, `filter`, `filterMap`, `foldr`, `append`, `join`, `pure`, `bind`, `replicate`, and
`reverse`.
* Additional functions defined in terms of these: `leftpad`, `rightPad`, and `reduceOption`.
* Operations using indexes: `mapIdx`.
* List membership: `isEmpty`, `elem`, `contains`, `mem` (and the `∈` notation),
and decidability for predicates quantifying over membership in a `List`.
* Sublists: `take`, `drop`, `takeWhile`, `dropWhile`, `partition`, `dropLast`,
`isPrefixOf`, `isPrefixOf?`, `isSuffixOf`, `isSuffixOf?`, `Subset`, `Sublist`,
`rotateLeft` and `rotateRight`.
* Manipulating elements: `replace`, `insert`, `modify`, `erase`, `eraseP`, `eraseIdx`.
* Manipulating elements: `replace`, `insert`, `erase`, `eraseP`, `eraseIdx`.
* Finding elements: `find?`, `findSome?`, `findIdx`, `indexOf`, `findIdx?`, `indexOf?`,
`countP`, `count`, and `lookup`.
* Logic: `any`, `all`, `or`, and `and`.
* Zippers: `zipWith`, `zip`, `zipWithAll`, and `unzip`.
* Ranges and enumeration: `range`, `iota`, `enumFrom`, and `enum`.
* Minima and maxima: `min?` and `max?`.
* Other functions: `intersperse`, `intercalate`, `eraseDups`, `eraseReps`, `span`, `splitBy`,
* Minima and maxima: `minimum?` and `maximum?`.
* Other functions: `intersperse`, `intercalate`, `eraseDups`, `eraseReps`, `span`, `groupBy`,
`removeAll`
(currently these functions are mostly only used in meta code,
and do not have API suitable for verification).
@@ -122,11 +121,6 @@ protected def beq [BEq α] : List α → List α → Bool
| a::as, b::bs => a == b && List.beq as bs
| _, _ => false
@[simp] theorem beq_nil_nil [BEq α] : List.beq ([] : List α) ([] : List α) = true := rfl
@[simp] theorem beq_cons_nil [BEq α] (a : α) (as : List α) : List.beq (a::as) [] = false := rfl
@[simp] theorem beq_nil_cons [BEq α] (a : α) (as : List α) : List.beq [] (a::as) = false := rfl
theorem beq_cons₂ [BEq α] (a b : α) (as bs : List α) : List.beq (a::as) (b::bs) = (a == b && List.beq as bs) := rfl
instance [BEq α] : BEq (List α) := List.beq
instance [BEq α] [LawfulBEq α] : LawfulBEq (List α) where
@@ -224,8 +218,8 @@ def get? : (as : List α) → (i : Nat) → Option α
theorem ext_get? : {l₁ l₂ : List α}, ( n, l₁.get? n = l₂.get? n) l₁ = l₂
| [], [], _ => rfl
| _ :: _, [], h => nomatch h 0
| [], _ :: _, h => nomatch h 0
| a :: l₁, [], h => nomatch h 0
| [], a' :: l₂, h => nomatch h 0
| a :: l₁, a' :: l₂, h => by
have h0 : some a = some a' := h 0
injection h0 with aa; simp only [aa, ext_get? fun n => h (n+1)]
@@ -374,7 +368,7 @@ def tailD (list fallback : List α) : List α :=
/-! ## Basic `List` operations.
We define the basic functional programming operations on `List`:
`map`, `filter`, `filterMap`, `foldr`, `append`, `flatten`, `pure`, `bind`, `replicate`, and `reverse`.
`map`, `filter`, `filterMap`, `foldr`, `append`, `join`, `pure`, `bind`, `replicate`, and `reverse`.
-/
/-! ### map -/
@@ -548,53 +542,41 @@ theorem reverseAux_eq_append (as bs : List α) : reverseAux as bs = reverseAux a
simp [reverse, reverseAux]
rw [ reverseAux_eq_append]
/-! ### flatten -/
/-! ### join -/
/--
`O(|flatten L|)`. `join L` concatenates all the lists in `L` into one list.
* `flatten [[a], [], [b, c], [d, e, f]] = [a, b, c, d, e, f]`
`O(|join L|)`. `join L` concatenates all the lists in `L` into one list.
* `join [[a], [], [b, c], [d, e, f]] = [a, b, c, d, e, f]`
-/
def flatten : List (List α) List α
def join : List (List α) List α
| [] => []
| a :: as => a ++ flatten as
| a :: as => a ++ join as
@[simp] theorem flatten_nil : List.flatten ([] : List (List α)) = [] := rfl
@[simp] theorem flatten_cons : (l :: ls).flatten = l ++ ls.flatten := rfl
@[simp] theorem join_nil : List.join ([] : List (List α)) = [] := rfl
@[simp] theorem join_cons : (l :: ls).join = l ++ ls.join := rfl
@[deprecated flatten (since := "2024-10-14"), inherit_doc flatten] abbrev join := @flatten
/-! ### pure -/
/-! ### singleton -/
/-- `pure x = [x]` is the `pure` operation of the list monad. -/
@[inline] protected def pure {α : Type u} (a : α) : List α := [a]
/-- `singleton x = [x]`. -/
@[inline] protected def singleton {α : Type u} (a : α) : List α := [a]
set_option linter.missingDocs false in
@[deprecated singleton (since := "2024-10-16")] protected abbrev pure := @singleton
/-! ### flatMap -/
/-! ### bind -/
/--
`flatMap xs f` applies `f` to each element of `xs`
`bind xs f` is the bind operation of the list monad. It applies `f` to each element of `xs`
to get a list of lists, and then concatenates them all together.
* `[2, 3, 2].bind range = [0, 1, 0, 1, 2, 0, 1]`
-/
@[inline] def flatMap {α : Type u} {β : Type v} (a : List α) (b : α List β) : List β := flatten (map b a)
@[inline] protected def bind {α : Type u} {β : Type v} (a : List α) (b : α List β) : List β := join (map b a)
@[simp] theorem flatMap_nil (f : α List β) : List.flatMap [] f = [] := by simp [flatten, List.flatMap]
@[simp] theorem flatMap_cons x xs (f : α List β) :
List.flatMap (x :: xs) f = f x ++ List.flatMap xs f := by simp [flatten, List.flatMap]
@[simp] theorem bind_nil (f : α List β) : List.bind [] f = [] := by simp [join, List.bind]
@[simp] theorem bind_cons x xs (f : α List β) :
List.bind (x :: xs) f = f x ++ List.bind xs f := by simp [join, List.bind]
set_option linter.missingDocs false in
@[deprecated flatMap (since := "2024-10-16")] abbrev bind := @flatMap
@[deprecated bind_nil (since := "2024-06-15")] abbrev nil_bind := @bind_nil
set_option linter.missingDocs false in
@[deprecated flatMap_nil (since := "2024-10-16")] abbrev nil_flatMap := @flatMap_nil
set_option linter.missingDocs false in
@[deprecated flatMap_cons (since := "2024-10-16")] abbrev cons_flatMap := @flatMap_cons
set_option linter.missingDocs false in
@[deprecated flatMap_nil (since := "2024-06-15")] abbrev nil_bind := @flatMap_nil
set_option linter.missingDocs false in
@[deprecated flatMap_cons (since := "2024-06-15")] abbrev cons_bind := @flatMap_cons
@[deprecated bind_cons (since := "2024-06-15")] abbrev cons_bind := @bind_cons
/-! ### replicate -/
@@ -1119,35 +1101,6 @@ theorem replace_cons [BEq α] {a : α} :
@[inline] protected def insert [BEq α] (a : α) (l : List α) : List α :=
if l.elem a then l else a :: l
/-! ### modify -/
/--
Apply a function to the nth tail of `l`. Returns the input without
using `f` if the index is larger than the length of the List.
```
modifyTailIdx f 2 [a, b, c] = [a, b] ++ f [c]
```
-/
@[simp] def modifyTailIdx (f : List α List α) : Nat List α List α
| 0, l => f l
| _+1, [] => []
| n+1, a :: l => a :: modifyTailIdx f n l
/-- Apply `f` to the head of the list, if it exists. -/
@[inline] def modifyHead (f : α α) : List α List α
| [] => []
| a :: l => f a :: l
@[simp] theorem modifyHead_nil (f : α α) : [].modifyHead f = [] := by rw [modifyHead]
@[simp] theorem modifyHead_cons (a : α) (l : List α) (f : α α) :
(a :: l).modifyHead f = f a :: l := by rw [modifyHead]
/--
Apply `f` to the nth element of the list, if it exists, replacing that element with the result.
-/
def modify (f : α α) : Nat List α List α :=
modifyTailIdx (modifyHead f)
/-! ### erase -/
/--
@@ -1442,25 +1395,12 @@ def unzip : List (α × β) → List α × List β
/-! ## Ranges and enumeration -/
/-- Sum of a list.
`List.sum [a, b, c] = a + (b + (c + 0))` -/
def sum {α} [Add α] [Zero α] : List α α :=
foldr (· + ·) 0
@[simp] theorem sum_nil [Add α] [Zero α] : ([] : List α).sum = 0 := rfl
@[simp] theorem sum_cons [Add α] [Zero α] {a : α} {l : List α} : (a::l).sum = a + l.sum := rfl
/-- Sum of a list of natural numbers. -/
@[deprecated List.sum (since := "2024-10-17")]
-- This is not in the `List` namespace as later `List.sum` will be defined polymorphically.
protected def _root_.Nat.sum (l : List Nat) : Nat := l.foldr (·+·) 0
set_option linter.deprecated false in
@[simp, deprecated sum_nil (since := "2024-10-17")]
theorem _root_.Nat.sum_nil : Nat.sum ([] : List Nat) = 0 := rfl
set_option linter.deprecated false in
@[simp, deprecated sum_cons (since := "2024-10-17")]
theorem _root_.Nat.sum_cons (a : Nat) (l : List Nat) :
@[simp] theorem _root_.Nat.sum_nil : Nat.sum ([] : List Nat) = 0 := rfl
@[simp] theorem _root_.Nat.sum_cons (a : Nat) (l : List Nat) :
Nat.sum (a::l) = a + Nat.sum l := rfl
/-! ### range -/
@@ -1524,34 +1464,30 @@ def enum : List α → List (Nat × α) := enumFrom 0
/-! ## Minima and maxima -/
/-! ### min? -/
/-! ### minimum? -/
/--
Returns the smallest element of the list, if it is not empty.
* `[].min? = none`
* `[4].min? = some 4`
* `[1, 4, 2, 10, 6].min? = some 1`
* `[].minimum? = none`
* `[4].minimum? = some 4`
* `[1, 4, 2, 10, 6].minimum? = some 1`
-/
def min? [Min α] : List α Option α
def minimum? [Min α] : List α Option α
| [] => none
| a::as => some <| as.foldl min a
@[inherit_doc min?, deprecated min? (since := "2024-09-29")] abbrev minimum? := @min?
/-! ### max? -/
/-! ### maximum? -/
/--
Returns the largest element of the list, if it is not empty.
* `[].max? = none`
* `[4].max? = some 4`
* `[1, 4, 2, 10, 6].max? = some 10`
* `[].maximum? = none`
* `[4].maximum? = some 4`
* `[1, 4, 2, 10, 6].maximum? = some 10`
-/
def max? [Max α] : List α Option α
def maximum? [Max α] : List α Option α
| [] => none
| a::as => some <| as.foldl max a
@[inherit_doc max?, deprecated max? (since := "2024-09-29")] abbrev maximum? := @max?
/-! ## Other list operations
The functions are currently mostly used in meta code,
@@ -1587,7 +1523,7 @@ def intersperse (sep : α) : List α → List α
* `intercalate sep [a, b, c] = a ++ sep ++ b ++ sep ++ c`
-/
def intercalate (sep : List α) (xs : List (List α)) : List α :=
(intersperse sep xs).flatten
join (intersperse sep xs)
/-! ### eraseDups -/
@@ -1639,23 +1575,23 @@ where
| true => loop as (a::rs)
| false => (rs.reverse, a::as)
/-! ### splitBy -/
/-! ### groupBy -/
/--
`O(|l|)`. `splitBy R l` splits `l` into chains of elements
`O(|l|)`. `groupBy R l` splits `l` into chains of elements
such that adjacent elements are related by `R`.
* `splitBy (·==·) [1, 1, 2, 2, 2, 3, 2] = [[1, 1], [2, 2, 2], [3], [2]]`
* `splitBy (·<·) [1, 2, 5, 4, 5, 1, 4] = [[1, 2, 5], [4, 5], [1, 4]]`
* `groupBy (·==·) [1, 1, 2, 2, 2, 3, 2] = [[1, 1], [2, 2, 2], [3], [2]]`
* `groupBy (·<·) [1, 2, 5, 4, 5, 1, 4] = [[1, 2, 5], [4, 5], [1, 4]]`
-/
@[specialize] def splitBy (R : α α Bool) : List α List (List α)
@[specialize] def groupBy (R : α α Bool) : List α List (List α)
| [] => []
| a::as => loop as a [] []
where
/--
The arguments of `splitBy.loop l ag g gs` represent the following:
The arguments of `groupBy.loop l ag g gs` represent the following:
- `l : List α` are the elements which we still need to split.
- `l : List α` are the elements which we still need to group.
- `ag : α` is the previous element for which a comparison was performed.
- `g : List α` is the group currently being assembled, in **reverse order**.
- `gs : List (List α)` is all of the groups that have been completed, in **reverse order**.
@@ -1666,8 +1602,6 @@ where
| false => loop as a [] ((ag::g).reverse::gs)
| [], ag, g, gs => ((ag::g).reverse::gs).reverse
@[deprecated splitBy (since := "2024-10-30"), inherit_doc splitBy] abbrev groupBy := @splitBy
/-! ### removeAll -/
/-- `O(|xs|)`. Computes the "set difference" of lists,

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@@ -232,12 +232,11 @@ theorem sizeOf_get [SizeOf α] (as : List α) (i : Fin as.length) : sizeOf (as.g
apply Nat.lt_trans ih
simp_arith
theorem le_antisymm [LT α] [s : Std.Antisymm (¬ · < · : α α Prop)]
{as bs : List α} (h₁ : as bs) (h₂ : bs as) : as = bs :=
theorem le_antisymm [LT α] [s : Antisymm (¬ · < · : α α Prop)] {as bs : List α} (h₁ : as bs) (h₂ : bs as) : as = bs :=
match as, bs with
| [], [] => rfl
| [], _::_ => False.elim <| h₂ (List.lt.nil ..)
| _::_, [] => False.elim <| h₁ (List.lt.nil ..)
| [], b::bs => False.elim <| h₂ (List.lt.nil ..)
| a::as, [] => False.elim <| h₁ (List.lt.nil ..)
| a::as, b::bs => by
by_cases hab : a < b
· exact False.elim <| h₂ (List.lt.head _ _ hab)
@@ -249,8 +248,7 @@ theorem le_antisymm [LT α] [s : Std.Antisymm (¬ · < · : αα → Prop)]
have : a = b := s.antisymm hab hba
simp [this, ih]
instance [LT α] [Std.Antisymm (¬ · < · : α α Prop)] :
Std.Antisymm (· · : List α List α Prop) where
instance [LT α] [Antisymm (¬ · < · : α α Prop)] : Antisymm (· · : List α List α Prop) where
antisymm h₁ h₂ := le_antisymm h₁ h₂
end List

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@@ -215,6 +215,27 @@ def findSomeM? {m : Type u → Type v} [Monad m] {α : Type w} {β : Type u} (f
| some b => pure (some b)
| none => findSomeM? f as
@[inline] protected def forIn {α : Type u} {β : Type v} {m : Type v Type w} [Monad m] (as : List α) (init : β) (f : α β m (ForInStep β)) : m β :=
let rec @[specialize] loop
| [], b => pure b
| a::as, b => do
match ( f a b) with
| ForInStep.done b => pure b
| ForInStep.yield b => loop as b
loop as init
instance : ForIn m (List α) α where
forIn := List.forIn
@[simp] theorem forIn_eq_forIn [Monad m] : @List.forIn α β m _ = forIn := rfl
@[simp] theorem forIn_nil [Monad m] (f : α β m (ForInStep β)) (b : β) : forIn [] b f = pure b :=
rfl
@[simp] theorem forIn_cons [Monad m] (f : α β m (ForInStep β)) (a : α) (as : List α) (b : β)
: forIn (a::as) b f = f a b >>= fun | ForInStep.done b => pure b | ForInStep.yield b => forIn as b f :=
rfl
@[inline] protected def forIn' {α : Type u} {β : Type v} {m : Type v Type w} [Monad m] (as : List α) (init : β) (f : (a : α) a as β m (ForInStep β)) : m β :=
let rec @[specialize] loop : (as' : List α) (b : β) Exists (fun bs => bs ++ as' = as) m β
| [], b, _ => pure b
@@ -233,15 +254,14 @@ def findSomeM? {m : Type u → Type v} [Monad m] {α : Type w} {β : Type u} (f
instance : ForIn' m (List α) α inferInstance where
forIn' := List.forIn'
-- No separate `ForIn` instance is required because it can be derived from `ForIn'`.
@[simp] theorem forIn'_eq_forIn' [Monad m] : @List.forIn' α β m _ = forIn' := rfl
@[simp] theorem forIn'_nil [Monad m] (f : (a : α) a [] β m (ForInStep β)) (b : β) : forIn' [] b f = pure b :=
rfl
@[simp] theorem forIn_nil [Monad m] (f : α β m (ForInStep β)) (b : β) : forIn [] b f = pure b :=
rfl
@[simp] theorem forIn'_eq_forIn {α : Type u} {β : Type v} {m : Type v Type w} [Monad m] (as : List α) (init : β) (f : α β m (ForInStep β)) : forIn' as init (fun a _ b => f a b) = forIn as init f := by
simp [forIn', forIn, List.forIn, List.forIn']
have : cs h, List.forIn'.loop cs (fun a _ b => f a b) as init h = List.forIn.loop f as init := by
intro cs h
induction as generalizing cs init with
| nil => intros; rfl
| cons a as ih => intros; simp [List.forIn.loop, List.forIn'.loop, ih]
apply this
instance : ForM m (List α) α where
forM := List.forM

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@@ -153,15 +153,13 @@ theorem countP_filterMap (p : β → Bool) (f : α → Option β) (l : List α)
simp only [length_filterMap_eq_countP]
congr
ext a
simp +contextual [Option.getD_eq_iff, Option.isSome_eq_isSome]
simp (config := { contextual := true }) [Option.getD_eq_iff]
@[simp] theorem countP_flatten (l : List (List α)) :
countP p l.flatten = (l.map (countP p)).sum := by
simp only [countP_eq_length_filter, filter_flatten]
@[simp] theorem countP_join (l : List (List α)) :
countP p l.join = Nat.sum (l.map (countP p)) := by
simp only [countP_eq_length_filter, filter_join]
simp [countP_eq_length_filter']
@[deprecated countP_flatten (since := "2024-10-14")] abbrev countP_join := @countP_flatten
@[simp] theorem countP_reverse (l : List α) : countP p l.reverse = countP p l := by
simp [countP_eq_length_filter, filter_reverse]
@@ -232,10 +230,8 @@ theorem count_singleton (a b : α) : count a [b] = if b == a then 1 else 0 := by
@[simp] theorem count_append (a : α) : l₁ l₂, count a (l₁ ++ l₂) = count a l₁ + count a l₂ :=
countP_append _
theorem count_flatten (a : α) (l : List (List α)) : count a l.flatten = (l.map (count a)).sum := by
simp only [count_eq_countP, countP_flatten, count_eq_countP']
@[deprecated count_flatten (since := "2024-10-14")] abbrev count_join := @count_flatten
theorem count_join (a : α) (l : List (List α)) : count a l.join = Nat.sum (l.map (count a)) := by
simp only [count_eq_countP, countP_join, count_eq_countP']
@[simp] theorem count_reverse (a : α) (l : List α) : count a l.reverse = count a l := by
simp only [count_eq_countP, countP_eq_length_filter, filter_reverse, length_reverse]
@@ -315,7 +311,7 @@ theorem replicate_count_eq_of_count_eq_length {l : List α} (h : count a l = len
theorem count_le_count_map [DecidableEq β] (l : List α) (f : α β) (x : α) :
count x l count (f x) (map f l) := by
rw [count, count, countP_map]
apply countP_mono_left; simp +contextual
apply countP_mono_left; simp (config := { contextual := true })
theorem count_filterMap {α} [BEq β] (b : β) (f : α Option β) (l : List α) :
count b (filterMap f l) = countP (fun a => f a == some b) l := by

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@@ -52,9 +52,9 @@ theorem eraseP_of_forall_not {l : List α} (h : ∀ a, a ∈ l → ¬p a) : l.er
theorem eraseP_ne_nil {xs : List α} {p : α Bool} : xs.eraseP p [] xs [] x, p x xs [x] := by
simp
theorem exists_of_eraseP : {l : List α} {a} (_ : a l) (_ : p a),
theorem exists_of_eraseP : {l : List α} {a} (al : a l) (pa : p a),
a l₁ l₂, ( b l₁, ¬p b) p a l = l₁ ++ a :: l₂ l.eraseP p = l₁ ++ l₂
| b :: l, _, al, pa =>
| b :: l, a, al, pa =>
if pb : p b then
b, [], l, forall_mem_nil _, pb, by simp [pb]
else
@@ -168,8 +168,8 @@ theorem eraseP_append_left {a : α} (pa : p a) :
theorem eraseP_append_right :
{l₁ : List α} l₂, ( b l₁, ¬p b) eraseP p (l₁++l₂) = l₁ ++ l₂.eraseP p
| [], _, _ => rfl
| _ :: _, _, h => by
| [], l₂, _ => rfl
| x :: xs, l₂, h => by
simp [(forall_mem_cons.1 h).1, eraseP_append_right _ (forall_mem_cons.1 h).2]
theorem eraseP_append (l₁ l₂ : List α) :

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@@ -132,14 +132,14 @@ theorem findSome?_append {l₁ l₂ : List α} : (l₁ ++ l₂).findSome? f = (l
simp only [cons_append, findSome?]
split <;> simp_all
theorem head_flatten {L : List (List α)} (h : l, l L l []) :
(flatten L).head (by simpa using h) = (L.findSome? fun l => l.head?).get (by simpa using h) := by
simp [head_eq_iff_head?_eq_some, head?_flatten]
theorem head_join {L : List (List α)} (h : l, l L l []) :
(join L).head (by simpa using h) = (L.findSome? fun l => l.head?).get (by simpa using h) := by
simp [head_eq_iff_head?_eq_some, head?_join]
theorem getLast_flatten {L : List (List α)} (h : l, l L l []) :
(flatten L).getLast (by simpa using h) =
theorem getLast_join {L : List (List α)} (h : l, l L l []) :
(join L).getLast (by simpa using h) =
(L.reverse.findSome? fun l => l.getLast?).get (by simpa using h) := by
simp [getLast_eq_iff_getLast_eq_some, getLast?_flatten]
simp [getLast_eq_iff_getLast_eq_some, getLast?_join]
theorem findSome?_replicate : findSome? f (replicate n a) = if n = 0 then none else f a := by
cases n with
@@ -179,7 +179,7 @@ theorem IsPrefix.findSome?_eq_some {l₁ l₂ : List α} {f : α → Option β}
List.findSome? f l₁ = some b List.findSome? f l₂ = some b := by
rw [IsPrefix] at h
obtain t, rfl := h
simp +contextual [findSome?_append]
simp (config := {contextual := true}) [findSome?_append]
theorem IsPrefix.findSome?_eq_none {l₁ l₂ : List α} {f : α Option β} (h : l₁ <+: l₂) :
List.findSome? f l₂ = none List.findSome? f l₁ = none :=
@@ -326,35 +326,35 @@ theorem get_find?_mem (xs : List α) (p : α → Bool) (h) : (xs.find? p).get h
simp only [cons_append, find?]
by_cases h : p x <;> simp [h, ih]
@[simp] theorem find?_flatten (xs : List (List α)) (p : α Bool) :
xs.flatten.find? p = xs.findSome? (·.find? p) := by
@[simp] theorem find?_join (xs : List (List α)) (p : α Bool) :
xs.join.find? p = xs.findSome? (·.find? p) := by
induction xs with
| nil => simp
| cons x xs ih =>
simp only [flatten_cons, find?_append, findSome?_cons, ih]
simp only [join_cons, find?_append, findSome?_cons, ih]
split <;> simp [*]
theorem find?_flatten_eq_none {xs : List (List α)} {p : α Bool} :
xs.flatten.find? p = none ys xs, x ys, !p x := by
theorem find?_join_eq_none {xs : List (List α)} {p : α Bool} :
xs.join.find? p = none ys xs, x ys, !p x := by
simp
/--
If `find? p` returns `some a` from `xs.flatten`, then `p a` holds, and
If `find? p` returns `some a` from `xs.join`, then `p a` holds, and
some list in `xs` contains `a`, and no earlier element of that list satisfies `p`.
Moreover, no earlier list in `xs` has an element satisfying `p`.
-/
theorem find?_flatten_eq_some {xs : List (List α)} {p : α Bool} {a : α} :
xs.flatten.find? p = some a
theorem find?_join_eq_some {xs : List (List α)} {p : α Bool} {a : α} :
xs.join.find? p = some a
p a as ys zs bs, xs = as ++ (ys ++ a :: zs) :: bs
( a as, x a, !p x) ( x ys, !p x) := by
rw [find?_eq_some]
constructor
· rintro h, ys, zs, h₁, h₂
refine h, ?_
rw [flatten_eq_append_iff] at h₁
rw [join_eq_append_iff] at h₁
obtain (as, bs, rfl, rfl, h₁ | as, bs, c, cs, ds, rfl, rfl, h₁) := h₁
· replace h₁ := h₁.symm
rw [flatten_eq_cons_iff] at h₁
rw [join_eq_cons_iff] at h₁
obtain bs, cs, ds, rfl, h₁, rfl := h₁
refine as ++ bs, [], cs, ds, by simp, ?_
simp
@@ -371,25 +371,21 @@ theorem find?_flatten_eq_some {xs : List (List α)} {p : α → Bool} {a : α} :
· intro x m
simpa using h₂ x (by simpa using .inr m)
· rintro h, as, ys, zs, bs, rfl, h₁, h₂
refine h, as.flatten ++ ys, zs ++ bs.flatten, by simp, ?_
refine h, as.join ++ ys, zs ++ bs.join, by simp, ?_
intro a m
simp at m
obtain l, ml, m | m := m
· exact h₁ l ml a m
· exact h₂ a m
@[simp] theorem find?_flatMap (xs : List α) (f : α List β) (p : β Bool) :
(xs.flatMap f).find? p = xs.findSome? (fun x => (f x).find? p) := by
simp [flatMap_def, findSome?_map]; rfl
@[simp] theorem find?_bind (xs : List α) (f : α List β) (p : β Bool) :
(xs.bind f).find? p = xs.findSome? (fun x => (f x).find? p) := by
simp [bind_def, findSome?_map]; rfl
@[deprecated find?_flatMap (since := "2024-10-16")] abbrev find?_bind := @find?_flatMap
theorem find?_flatMap_eq_none {xs : List α} {f : α List β} {p : β Bool} :
(xs.flatMap f).find? p = none x xs, y f x, !p y := by
theorem find?_bind_eq_none {xs : List α} {f : α List β} {p : β Bool} :
(xs.bind f).find? p = none x xs, y f x, !p y := by
simp
@[deprecated find?_flatMap_eq_none (since := "2024-10-16")] abbrev find?_bind_eq_none := @find?_flatMap_eq_none
theorem find?_replicate : find? p (replicate n a) = if n = 0 then none else if p a then some a else none := by
cases n
· simp
@@ -436,7 +432,7 @@ theorem IsPrefix.find?_eq_some {l₁ l₂ : List α} {p : α → Bool} (h : l₁
List.find? p l₁ = some b List.find? p l₂ = some b := by
rw [IsPrefix] at h
obtain t, rfl := h
simp +contextual [find?_append]
simp (config := {contextual := true}) [find?_append]
theorem IsPrefix.find?_eq_none {l₁ l₂ : List α} {p : α Bool} (h : l₁ <+: l₂) :
List.find? p l₂ = none List.find? p l₁ = none :=
@@ -562,7 +558,7 @@ theorem not_of_lt_findIdx {p : α → Bool} {xs : List α} {i : Nat} (h : i < xs
| inr e =>
have ipm := Nat.succ_pred_eq_of_pos e
have ilt := Nat.le_trans ho (findIdx_le_length p)
simp +singlePass only [ ipm, getElem_cons_succ]
simp (config := { singlePass := true }) only [ ipm, getElem_cons_succ]
rw [ ipm, Nat.succ_lt_succ_iff] at h
simpa using ih h
@@ -595,14 +591,15 @@ theorem findIdx_eq {p : α → Bool} {xs : List α} {i : Nat} (h : i < xs.length
theorem findIdx_append (p : α Bool) (l₁ l₂ : List α) :
(l₁ ++ l₂).findIdx p =
if l₁.findIdx p < l₁.length then l₁.findIdx p else l₂.findIdx p + l₁.length := by
if x, x l₁ p x = true then l₁.findIdx p else l₂.findIdx p + l₁.length := by
induction l₁ with
| nil => simp
| cons x xs ih =>
simp only [findIdx_cons, length_cons, cons_append]
by_cases h : p x
· simp [h]
· simp only [h, ih, cond_eq_if, Bool.false_eq_true, reduceIte, add_one_lt_add_one_iff]
· simp only [h, ih, cond_eq_if, Bool.false_eq_true, reduceIte, mem_cons, exists_eq_or_imp,
false_or]
split <;> simp [Nat.add_assoc]
theorem IsPrefix.findIdx_le {l₁ l₂ : List α} {p : α Bool} (h : l₁ <+: l₂) :
@@ -789,15 +786,15 @@ theorem findIdx?_of_eq_none {xs : List α} {p : α → Bool} (w : xs.findIdx? p
induction xs with simp
| cons _ _ _ => split <;> simp_all [Option.map_or', Option.map_map]; rfl
theorem findIdx?_flatten {l : List (List α)} {p : α Bool} :
l.flatten.findIdx? p =
theorem findIdx?_join {l : List (List α)} {p : α Bool} :
l.join.findIdx? p =
(l.findIdx? (·.any p)).map
fun i => ((l.take i).map List.length).sum +
fun i => Nat.sum ((l.take i).map List.length) +
(l[i]?.map fun xs => xs.findIdx p).getD 0 := by
induction l with
| nil => simp
| cons xs l ih =>
simp only [flatten, findIdx?_append, map_take, map_cons, findIdx?, any_eq_true, Nat.zero_add,
simp only [join, findIdx?_append, map_take, map_cons, findIdx?, any_eq_true, Nat.zero_add,
findIdx?_succ]
split
· simp only [Option.map_some', take_zero, sum_nil, length_cons, zero_lt_succ,
@@ -979,13 +976,4 @@ theorem IsInfix.lookup_eq_none {l₁ l₂ : List (α × β)} (h : l₁ <:+: l₂
end lookup
/-! ### Deprecations -/
@[deprecated head_flatten (since := "2024-10-14")] abbrev head_join := @head_flatten
@[deprecated getLast_flatten (since := "2024-10-14")] abbrev getLast_join := @getLast_flatten
@[deprecated find?_flatten (since := "2024-10-14")] abbrev find?_join := @find?_flatten
@[deprecated find?_flatten_eq_none (since := "2024-10-14")] abbrev find?_join_eq_none := @find?_flatten_eq_none
@[deprecated find?_flatten_eq_some (since := "2024-10-14")] abbrev find?_join_eq_some := @find?_flatten_eq_some
@[deprecated findIdx?_flatten (since := "2024-10-14")] abbrev findIdx?_join := @findIdx?_flatten
end List

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@@ -23,7 +23,7 @@ namespace List
The following operations are already tail-recursive, and do not need `@[csimp]` replacements:
`get`, `foldl`, `beq`, `isEqv`, `reverse`, `elem` (and hence `contains`), `drop`, `dropWhile`,
`partition`, `isPrefixOf`, `isPrefixOf?`, `find?`, `findSome?`, `lookup`, `any` (and hence `or`),
`all` (and hence `and`) , `range`, `eraseDups`, `eraseReps`, `span`, `splitBy`.
`all` (and hence `and`) , `range`, `eraseDups`, `eraseReps`, `span`, `groupBy`.
The following operations are still missing `@[csimp]` replacements:
`concat`, `zipWithAll`.
@@ -31,14 +31,14 @@ The following operations are still missing `@[csimp]` replacements:
The following operations are not recursive to begin with
(or are defined in terms of recursive primitives):
`isEmpty`, `isSuffixOf`, `isSuffixOf?`, `rotateLeft`, `rotateRight`, `insert`, `zip`, `enum`,
`min?`, `max?`, and `removeAll`.
`minimum?`, `maximum?`, and `removeAll`.
The following operations were already given `@[csimp]` replacements in `Init/Data/List/Basic.lean`:
`length`, `map`, `filter`, `replicate`, `leftPad`, `unzip`, `range'`, `iota`, `intersperse`.
The following operations are given `@[csimp]` replacements below:
`set`, `filterMap`, `foldr`, `append`, `bind`, `join`,
`take`, `takeWhile`, `dropLast`, `replace`, `modify`, `erase`, `eraseIdx`, `zipWith`,
`take`, `takeWhile`, `dropLast`, `replace`, `erase`, `eraseIdx`, `zipWith`,
`enumFrom`, and `intercalate`.
-/
@@ -93,29 +93,29 @@ The following operations are given `@[csimp]` replacements below:
@[csimp] theorem foldr_eq_foldrTR : @foldr = @foldrTR := by
funext α β f init l; simp [foldrTR, Array.foldr_eq_foldr_toList, -Array.size_toArray]
/-! ### flatMap -/
/-! ### bind -/
/-- Tail recursive version of `List.flatMap`. -/
@[inline] def flatMapTR (as : List α) (f : α List β) : List β := go as #[] where
/-- Auxiliary for `flatMap`: `flatMap.go f as = acc.toList ++ bind f as` -/
/-- Tail recursive version of `List.bind`. -/
@[inline] def bindTR (as : List α) (f : α List β) : List β := go as #[] where
/-- Auxiliary for `bind`: `bind.go f as = acc.toList ++ bind f as` -/
@[specialize] go : List α Array β List β
| [], acc => acc.toList
| x::xs, acc => go xs (acc ++ f x)
@[csimp] theorem flatMap_eq_flatMapTR : @List.flatMap = @flatMapTR := by
@[csimp] theorem bind_eq_bindTR : @List.bind = @bindTR := by
funext α β as f
let rec go : as acc, flatMapTR.go f as acc = acc.toList ++ as.flatMap f
| [], acc => by simp [flatMapTR.go, flatMap]
| x::xs, acc => by simp [flatMapTR.go, flatMap, go xs]
let rec go : as acc, bindTR.go f as acc = acc.toList ++ as.bind f
| [], acc => by simp [bindTR.go, bind]
| x::xs, acc => by simp [bindTR.go, bind, go xs]
exact (go as #[]).symm
/-! ### flatten -/
/-! ### join -/
/-- Tail recursive version of `List.flatten`. -/
@[inline] def flattenTR (l : List (List α)) : List α := flatMapTR l id
/-- Tail recursive version of `List.join`. -/
@[inline] def joinTR (l : List (List α)) : List α := bindTR l id
@[csimp] theorem flatten_eq_flattenTR : @flatten = @flattenTR := by
funext α l; rw [ List.flatMap_id, List.flatMap_eq_flatMapTR]; rfl
@[csimp] theorem join_eq_joinTR : @join = @joinTR := by
funext α l; rw [ List.bind_id, List.bind_eq_bindTR]; rfl
/-! ## Sublists -/
@@ -197,24 +197,6 @@ The following operations are given `@[csimp]` replacements below:
· simp [*]
· intro h; rw [IH] <;> simp_all
/-! ### modify -/
/-- Tail-recursive version of `modify`. -/
def modifyTR (f : α α) (n : Nat) (l : List α) : List α := go l n #[] where
/-- Auxiliary for `modifyTR`: `modifyTR.go f l n acc = acc.toList ++ modify f n l`. -/
go : List α Nat Array α List α
| [], _, acc => acc.toList
| a :: l, 0, acc => acc.toListAppend (f a :: l)
| a :: l, n+1, acc => go l n (acc.push a)
theorem modifyTR_go_eq : l n, modifyTR.go f l n acc = acc.toList ++ modify f n l
| [], n => by cases n <;> simp [modifyTR.go, modify]
| a :: l, 0 => by simp [modifyTR.go, modify]
| a :: l, n+1 => by simp [modifyTR.go, modify, modifyTR_go_eq l]
@[csimp] theorem modify_eq_modifyTR : @modify = @modifyTR := by
funext α f n l; simp [modifyTR, modifyTR_go_eq]
/-! ### erase -/
/-- Tail recursive version of `List.erase`. -/
@@ -340,7 +322,7 @@ where
| [_] => simp
| x::y::xs =>
let rec go {acc x} : xs,
intercalateTR.go sep.toArray x xs acc = acc.toList ++ flatten (intersperse sep (x::xs))
intercalateTR.go sep.toArray x xs acc = acc.toList ++ join (intersperse sep (x::xs))
| [] => by simp [intercalateTR.go]
| _::_ => by simp [intercalateTR.go, go]
simp [intersperse, go]

View File

@@ -55,7 +55,7 @@ See also
* `Init.Data.List.Erase` for lemmas about `List.eraseP` and `List.erase`.
* `Init.Data.List.Find` for lemmas about `List.find?`, `List.findSome?`, `List.findIdx`,
`List.findIdx?`, and `List.indexOf`
* `Init.Data.List.MinMax` for lemmas about `List.min?` and `List.max?`.
* `Init.Data.List.MinMax` for lemmas about `List.minimum?` and `List.maximum?`.
* `Init.Data.List.Pairwise` for lemmas about `List.Pairwise` and `List.Nodup`.
* `Init.Data.List.Sublist` for lemmas about `List.Subset`, `List.Sublist`, `List.IsPrefix`,
`List.IsSuffix`, and `List.IsInfix`.
@@ -191,7 +191,7 @@ 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?_len_le hn e
this, by rwa [get?_eq_get this, Option.some.injEq] at e,
fun _, e => e get?_eq_get _
fun h, e => e get?_eq_get _
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
@@ -203,9 +203,6 @@ theorem get?_eq_none : l.get? n = none ↔ length l ≤ n :=
@[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
@@ -492,6 +489,10 @@ theorem getElem?_of_mem {a} {l : List α} (h : a ∈ l) : ∃ n : Nat, l[n]? = s
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 getElem_mem : {l : List α} {n} (h : n < l.length), l[n]'h l
| _ :: _, 0, _ => .head ..
| _ :: l, _+1, _ => .tail _ (getElem_mem (l := l) ..)
theorem get_mem : (l : List α) n h, get l n, h l
| _ :: _, 0, _ => .head ..
| _ :: l, _+1, _ => .tail _ (get_mem l ..)
@@ -714,9 +715,9 @@ theorem set_eq_of_length_le {l : List α} {n : Nat} (h : l.length ≤ n) {a : α
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
| _+1, 0, _ :: _, _ => by simp [set]
| 0, _+1, _ :: _, _ => by simp [set]
| _+1, _+1, _ :: t, h =>
| n+1, 0, _ :: _, _ => by simp [set]
| 0, m+1, _ :: _, _ => by simp [set]
| n+1, m+1, x :: t, h =>
congrArg _ <| set_comm a b t fun h' => h <| Nat.succ_inj'.mpr h'
@[simp]
@@ -877,20 +878,6 @@ theorem foldr_map' {α β : Type u} (g : α → β) (f : ααα) (f' :
· simp
· simp [*, h]
theorem foldl_assoc {op : α α α} [ha : Std.Associative op] :
{l : List α} {a₁ a₂}, l.foldl op (op a₁ a₂) = op a₁ (l.foldl op a₂)
| [], a₁, a₂ => rfl
| a :: l, a₁, a₂ => by
simp only [foldl_cons, ha.assoc]
rw [foldl_assoc]
theorem foldr_assoc {op : α α α} [ha : Std.Associative op] :
{l : List α} {a₁ a₂}, l.foldr op (op a₁ a₂) = op (l.foldr op a₁) a₂
| [], a₁, a₂ => rfl
| a :: l, a₁, a₂ => by
simp only [foldr_cons, ha.assoc]
rw [foldr_assoc]
theorem foldl_hom (f : α₁ α₂) (g₁ : α₁ β α₁) (g₂ : α₂ β α₂) (l : List β) (init : α₁)
(H : x y, g₂ (f x) y = f (g₁ x y)) : l.foldl g₂ (f init) = f (l.foldl g₁ init) := by
induction l generalizing init <;> simp [*, H]
@@ -990,8 +977,8 @@ theorem getLast_eq_getElem : ∀ (l : List α) (h : l ≠ []),
match l with
| [] => contradiction
| a :: l => exact Nat.le_refl _)
| [_], _ => rfl
| _ :: _ :: _, _ => by
| [a], h => rfl
| a :: b :: l, h => by
simp [getLast, get, Nat.succ_sub_succ, getLast_eq_getElem]
@[deprecated getLast_eq_getElem (since := "2024-07-15")]
@@ -1017,14 +1004,14 @@ theorem getLast_eq_getLastD (a l h) : @getLast α (a::l) h = getLastD l a := by
theorem getLast!_cons [Inhabited α] : @getLast! α _ (a::l) = getLastD l a := by
simp [getLast!, getLast_eq_getLastD]
@[simp] theorem getLast_mem : {l : List α} (h : l []), getLast l h l
theorem getLast_mem : {l : List α} (h : l []), getLast l h l
| [], h => absurd rfl h
| [_], _ => .head ..
| _::a::l, _ => .tail _ <| getLast_mem (cons_ne_nil a l)
theorem getLast_mem_getLast? : {l : List α} (h : l []), getLast l h getLast? l
| [], h => by contradiction
| _ :: _, _ => rfl
| a :: l, _ => rfl
theorem getLastD_mem_cons : (l : List α) (a : α), getLastD l a a::l
| [], _ => .head ..
@@ -1043,6 +1030,9 @@ theorem get_cons_length (x : α) (xs : List α) (n : Nat) (h : n = xs.length) :
@[simp] theorem getLast?_singleton (a : α) : getLast? [a] = a := rfl
theorem getLast!_of_getLast? [Inhabited α] : {l : List α}, getLast? l = some a getLast! l = a
| _ :: _, rfl => rfl
theorem getLast?_eq_getLast : l h, @getLast? α l = some (getLast l h)
| [], h => nomatch h rfl
| _ :: _, _ => rfl
@@ -1076,21 +1066,6 @@ theorem getLast?_concat (l : List α) : getLast? (l ++ [a]) = some a := by
theorem getLastD_concat (a b l) : @getLastD α (l ++ [b]) a = b := by
rw [getLastD_eq_getLast?, getLast?_concat]; rfl
/-! ### getLast! -/
@[simp] theorem getLast!_nil [Inhabited α] : ([] : List α).getLast! = default := rfl
theorem getLast!_of_getLast? [Inhabited α] : {l : List α}, getLast? l = some a getLast! l = a
| _ :: _, rfl => rfl
theorem getLast!_eq_getElem! [Inhabited α] {l : List α} : l.getLast! = l[l.length - 1]! := by
cases l with
| nil => simp
| cons _ _ =>
apply getLast!_of_getLast?
rw [getElem!_pos, getElem_cons_length (h := by simp)]
rfl
/-! ## Head and tail -/
/-! ### head -/
@@ -1127,7 +1102,7 @@ theorem head?_eq_some_iff {xs : List α} {a : α} : xs.head? = some a ↔ ∃ ys
@[simp] theorem head?_isSome : l.head?.isSome l [] := by
cases l <;> simp
@[simp] theorem head_mem : {l : List α} (h : l []), head l h l
theorem head_mem : {l : List α} (h : l []), head l h l
| [], h => absurd rfl h
| _::_, _ => .head ..
@@ -1142,7 +1117,7 @@ theorem mem_of_mem_head? : ∀ {l : List α} {a : α}, a ∈ l.head? → a ∈ l
theorem head_mem_head? : {l : List α} (h : l []), head l h head? l
| [], h => by contradiction
| _ :: _, _ => rfl
| a :: l, _ => rfl
theorem head?_concat {a : α} : (l ++ [a]).head? = l.head?.getD a := by
cases l <;> simp
@@ -1351,12 +1326,12 @@ theorem set_map {f : α → β} {l : List α} {n : Nat} {a : α} :
simp
@[simp] theorem head_map (f : α β) (l : List α) (w) :
(map f l).head w = f (l.head (by simpa using w)) := by
head (map f l) w = f (head l (by simpa using w)) := by
cases l
· simp at w
· simp_all
@[simp] theorem head?_map (f : α β) (l : List α) : (map f l).head? = l.head?.map f := by
@[simp] theorem head?_map (f : α β) (l : List α) : head? (map f l) = (head? l).map f := by
cases l <;> rfl
@[simp] theorem map_tail? (f : α β) (l : List α) : (tail? l).map (map f) = tail? (map f l) := by
@@ -1474,7 +1449,7 @@ theorem map_filter_eq_foldr (f : α → β) (p : α → Bool) (as : List α) :
@[simp] theorem filter_append {p : α Bool} :
(l₁ l₂ : List α), filter p (l₁ ++ l₂) = filter p l₁ ++ filter p l₂
| [], _ => rfl
| [], l₂ => rfl
| a :: l₁, l₂ => by simp [filter]; split <;> simp [filter_append l₁]
theorem filter_eq_cons_iff {l} {a} {as} :
@@ -1679,11 +1654,6 @@ theorem filterMap_eq_cons_iff {l} {b} {bs} :
/-! ### append -/
@[simp] theorem nil_append_fun : (([] : List α) ++ ·) = id := rfl
@[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) :
(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'
@@ -1698,7 +1668,7 @@ theorem getElem?_append_left {l₁ l₂ : List α} {n : Nat} (hn : n < l₁.leng
theorem getElem?_append_right : {l₁ l₂ : List α} {n : Nat}, l₁.length n
(l₁ ++ l₂)[n]? = l₂[n - l₁.length]?
| [], _, _, _ => rfl
| [], _, n, _ => rfl
| a :: l, _, n+1, h₁ => by
rw [cons_append]
simp [Nat.succ_sub_succ_eq_sub, getElem?_append_right (Nat.lt_succ.1 h₁)]
@@ -1763,8 +1733,8 @@ theorem append_of_mem {a : α} {l : List α} : a ∈ l → ∃ s t : List α, l
theorem append_inj :
{s₁ s₂ t₁ t₂ : List α}, s₁ ++ t₁ = s₂ ++ t₂ length s₁ = length s₂ s₁ = s₂ t₁ = t₂
| [], [], _, _, h, _ => rfl, h
| _ :: _, _ :: _, _, _, h, hl => by
| [], [], t₁, t₂, h, _ => rfl, h
| a :: s₁, b :: s₂, t₁, t₂, h, hl => by
simp [append_inj (cons.inj h).2 (Nat.succ.inj hl)] at h ; exact h
theorem append_inj_right (h : s₁ ++ t₁ = s₂ ++ t₂) (hl : length s₁ = length s₂) : t₁ = t₂ :=
@@ -2076,97 +2046,106 @@ theorem eq_nil_or_concat : ∀ l : List α, l = [] ∃ L b, l = concat L b
| _, .inl rfl => .inr [], a, rfl
| _, .inr L, b, rfl => .inr a::L, b, rfl
/-! ### flatten -/
/-! ### join -/
@[simp] theorem length_flatten (L : List (List α)) : (flatten L).length = (L.map length).sum := by
@[simp] theorem length_join (L : List (List α)) : (join L).length = Nat.sum (L.map length) := by
induction L with
| nil => rfl
| cons =>
simp [flatten, length_append, *]
simp [join, length_append, *]
theorem flatten_singleton (l : List α) : [l].flatten = l := by simp
theorem join_singleton (l : List α) : [l].join = l := by simp
@[simp] theorem mem_flatten : {L : List (List α)}, a L.flatten l, l L a l
@[simp] theorem mem_join : {L : List (List α)}, a L.join l, l L a l
| [] => by simp
| b :: l => by simp [mem_flatten, or_and_right, exists_or]
| b :: l => by simp [mem_join, or_and_right, exists_or]
@[simp] theorem flatten_eq_nil_iff {L : List (List α)} : L.flatten = [] l L, l = [] := by
@[simp] theorem join_eq_nil_iff {L : List (List α)} : L.join = [] l L, l = [] := by
induction L <;> simp_all
theorem flatten_ne_nil_iff {xs : List (List α)} : xs.flatten [] x, x xs x [] := by
@[deprecated join_eq_nil_iff (since := "2024-09-05")] abbrev join_eq_nil := @join_eq_nil_iff
theorem join_ne_nil_iff {xs : List (List α)} : xs.join [] x, x xs x [] := by
simp
theorem exists_of_mem_flatten : a flatten L l, l L a l := mem_flatten.1
@[deprecated join_ne_nil_iff (since := "2024-09-05")] abbrev join_ne_nil := @join_ne_nil_iff
theorem mem_flatten_of_mem (lL : l L) (al : a l) : a flatten L := mem_flatten.2 l, lL, al
theorem exists_of_mem_join : a join L l, l L a l := mem_join.1
theorem forall_mem_flatten {p : α Prop} {L : List (List α)} :
( (x) (_ : x flatten L), p x) (l) (_ : l L) (x) (_ : x l), p x := by
simp only [mem_flatten, forall_exists_index, and_imp]
theorem mem_join_of_mem (lL : l L) (al : a l) : a join L := mem_join.2 l, lL, al
theorem forall_mem_join {p : α Prop} {L : List (List α)} :
( (x) (_ : x join L), p x) (l) (_ : l L) (x) (_ : x l), p x := by
simp only [mem_join, forall_exists_index, and_imp]
constructor <;> (intros; solve_by_elim)
theorem flatten_eq_flatMap {L : List (List α)} : flatten L = L.flatMap id := by
induction L <;> simp [List.flatMap]
theorem join_eq_bind {L : List (List α)} : join L = L.bind id := by
induction L <;> simp [List.bind]
theorem head?_flatten {L : List (List α)} : (flatten L).head? = L.findSome? fun l => l.head? := by
theorem head?_join {L : List (List α)} : (join L).head? = L.findSome? fun l => l.head? := by
induction L with
| nil => rfl
| cons =>
simp only [findSome?_cons]
split <;> simp_all
-- `getLast?_flatten` is proved later, after the `reverse` section.
-- `head_flatten` and `getLast_flatten` are proved in `Init.Data.List.Find`.
-- `getLast?_join` is proved later, after the `reverse` section.
-- `head_join` and `getLast_join` are proved in `Init.Data.List.Find`.
theorem foldl_flatten (f : β α β) (b : β) (L : List (List α)) :
(flatten L).foldl f b = L.foldl (fun b l => l.foldl f b) b := by
theorem foldl_join (f : β α β) (b : β) (L : List (List α)) :
(join L).foldl f b = L.foldl (fun b l => l.foldl f b) b := by
induction L generalizing b <;> simp_all
theorem foldr_flatten (f : α β β) (b : β) (L : List (List α)) :
(flatten L).foldr f b = L.foldr (fun l b => l.foldr f b) b := by
theorem foldr_join (f : α β β) (b : β) (L : List (List α)) :
(join L).foldr f b = L.foldr (fun l b => l.foldr f b) b := by
induction L <;> simp_all
@[simp] theorem map_flatten (f : α β) (L : List (List α)) : map f (flatten L) = flatten (map (map f) L) := by
@[simp] theorem map_join (f : α β) (L : List (List α)) : map f (join L) = join (map (map f) L) := by
induction L <;> simp_all
@[simp] theorem filterMap_flatten (f : α Option β) (L : List (List α)) :
filterMap f (flatten L) = flatten (map (filterMap f) L) := by
@[simp] theorem filterMap_join (f : α Option β) (L : List (List α)) :
filterMap f (join L) = join (map (filterMap f) L) := by
induction L <;> simp [*, filterMap_append]
@[simp] theorem filter_flatten (p : α Bool) (L : List (List α)) :
filter p (flatten L) = flatten (map (filter p) L) := by
@[simp] theorem filter_join (p : α Bool) (L : List (List α)) :
filter p (join L) = join (map (filter p) L) := by
induction L <;> simp [*, filter_append]
theorem flatten_filter_not_isEmpty :
{L : List (List α)}, flatten (L.filter fun l => !l.isEmpty) = L.flatten
theorem join_filter_not_isEmpty :
{L : List (List α)}, join (L.filter fun l => !l.isEmpty) = L.join
| [] => rfl
| [] :: L
| (a :: l) :: L => by
simp [flatten_filter_not_isEmpty (L := L)]
simp [join_filter_not_isEmpty (L := L)]
theorem flatten_filter_ne_nil [DecidablePred fun l : List α => l []] {L : List (List α)} :
flatten (L.filter fun l => l []) = L.flatten := by
theorem join_filter_ne_nil [DecidablePred fun l : List α => l []] {L : List (List α)} :
join (L.filter fun l => l []) = L.join := by
simp only [ne_eq, isEmpty_iff, Bool.not_eq_true, Bool.decide_eq_false,
flatten_filter_not_isEmpty]
join_filter_not_isEmpty]
@[simp] theorem flatten_append (L₁ L₂ : List (List α)) : flatten (L₁ ++ L₂) = flatten L₁ ++ flatten L₂ := by
@[deprecated filter_join (since := "2024-08-26")]
theorem join_map_filter (p : α Bool) (l : List (List α)) :
(l.map (filter p)).join = (l.join).filter p := by
rw [filter_join]
@[simp] theorem join_append (L₁ L₂ : List (List α)) : join (L₁ ++ L₂) = join L₁ ++ join L₂ := by
induction L₁ <;> simp_all
theorem flatten_concat (L : List (List α)) (l : List α) : flatten (L ++ [l]) = flatten L ++ l := by
theorem join_concat (L : List (List α)) (l : List α) : join (L ++ [l]) = join L ++ l := by
simp
theorem flatten_flatten {L : List (List (List α))} : flatten (flatten L) = flatten (map flatten L) := by
theorem join_join {L : List (List (List α))} : join (join L) = join (map join L) := by
induction L <;> simp_all
theorem flatten_eq_cons_iff {xs : List (List α)} {y : α} {ys : List α} :
xs.flatten = y :: ys
as bs cs, xs = as ++ (y :: bs) :: cs ( l, l as l = []) ys = bs ++ cs.flatten := by
theorem join_eq_cons_iff {xs : List (List α)} {y : α} {ys : List α} :
xs.join = y :: ys
as bs cs, xs = as ++ (y :: bs) :: cs ( l, l as l = []) ys = bs ++ cs.join := by
constructor
· induction xs with
| nil => simp
| cons x xs ih =>
intro h
simp only [flatten_cons] at h
simp only [join_cons] at h
replace h := h.symm
rw [cons_eq_append_iff] at h
obtain (rfl, h | z) := h
@@ -2177,23 +2156,23 @@ theorem flatten_eq_cons_iff {xs : List (List α)} {y : α} {ys : List α} :
refine [], a', xs, ?_
simp
· rintro as, bs, cs, rfl, h₁, rfl
simp [flatten_eq_nil_iff.mpr h₁]
simp [join_eq_nil_iff.mpr h₁]
theorem flatten_eq_append_iff {xs : List (List α)} {ys zs : List α} :
xs.flatten = ys ++ zs
( as bs, xs = as ++ bs ys = as.flatten zs = bs.flatten)
as bs c cs ds, xs = as ++ (bs ++ c :: cs) :: ds ys = as.flatten ++ bs
zs = c :: cs ++ ds.flatten := by
theorem join_eq_append_iff {xs : List (List α)} {ys zs : List α} :
xs.join = ys ++ zs
( as bs, xs = as ++ bs ys = as.join zs = bs.join)
as bs c cs ds, xs = as ++ (bs ++ c :: cs) :: ds ys = as.join ++ bs
zs = c :: cs ++ ds.join := by
constructor
· induction xs generalizing ys with
| nil =>
simp only [flatten_nil, nil_eq, append_eq_nil, and_false, cons_append, false_and, exists_const,
simp only [join_nil, nil_eq, append_eq_nil, and_false, cons_append, false_and, exists_const,
exists_false, or_false, and_imp, List.cons_ne_nil]
rintro rfl rfl
exact [], [], by simp
| cons x xs ih =>
intro h
simp only [flatten_cons] at h
simp only [join_cons] at h
rw [append_eq_append_iff] at h
obtain (ys, rfl, h | c', rfl, h) := h
· obtain (as, bs, rfl, rfl, rfl | as, bs, c, cs, ds, rfl, rfl, rfl) := ih h
@@ -2207,15 +2186,18 @@ theorem flatten_eq_append_iff {xs : List (List α)} {ys zs : List α} :
· simp
· simp
/-- Two lists of sublists are equal iff their flattens coincide, as well as the lengths of the
@[deprecated join_eq_cons_iff (since := "2024-09-05")] abbrev join_eq_cons := @join_eq_cons_iff
@[deprecated join_eq_append_iff (since := "2024-09-05")] abbrev join_eq_append := @join_eq_append_iff
/-- Two lists of sublists are equal iff their joins coincide, as well as the lengths of the
sublists. -/
theorem eq_iff_flatten_eq : {L L' : List (List α)},
L = L' L.flatten = L'.flatten map length L = map length L'
theorem eq_iff_join_eq : {L L' : List (List α)},
L = L' L.join = L'.join map length L = map length L'
| _, [] => by simp_all
| [], x' :: L' => by simp_all
| x :: L, x' :: L' => by
simp
rw [eq_iff_flatten_eq]
rw [eq_iff_join_eq]
constructor
· rintro rfl, h₁, h₂
simp_all
@@ -2223,86 +2205,86 @@ theorem eq_iff_flatten_eq : ∀ {L L' : List (List α)},
obtain rfl, h := append_inj h₁ h₂
exact rfl, h, h₃
/-! ### flatMap -/
/-! ### bind -/
theorem flatMap_def (l : List α) (f : α List β) : l.flatMap f = flatten (map f l) := by rfl
theorem bind_def (l : List α) (f : α List β) : l.bind f = join (map f l) := by rfl
@[simp] theorem flatMap_id (l : List (List α)) : List.flatMap l id = l.flatten := by simp [flatMap_def]
@[simp] theorem bind_id (l : List (List α)) : List.bind l id = l.join := by simp [bind_def]
@[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]
@[simp] theorem mem_bind {f : α List β} {b} {l : List α} : b l.bind f a, a l b f a := by
simp [bind_def, mem_join]
exact fun _, a, h₁, rfl, h₂ => a, h₁, h₂, fun a, h₁, h₂ => _, a, h₁, rfl, h₂
theorem exists_of_mem_flatMap {b : β} {l : List α} {f : α List β} :
b l.flatMap f a, a l b f a := mem_flatMap.1
theorem exists_of_mem_bind {b : β} {l : List α} {f : α List β} :
b l.bind f a, a l b f a := mem_bind.1
theorem mem_flatMap_of_mem {b : β} {l : List α} {f : α List β} {a} (al : a l) (h : b f a) :
b l.flatMap f := mem_flatMap.2 a, al, h
theorem mem_bind_of_mem {b : β} {l : List α} {f : α List β} {a} (al : a l) (h : b f a) :
b l.bind f := mem_bind.2 a, al, h
@[simp]
theorem flatMap_eq_nil_iff {l : List α} {f : α List β} : List.flatMap l f = [] x l, f x = [] :=
flatten_eq_nil_iff.trans <| by
theorem bind_eq_nil_iff {l : List α} {f : α List β} : List.bind l f = [] x l, f x = [] :=
join_eq_nil_iff.trans <| by
simp only [mem_map, forall_exists_index, and_imp, forall_apply_eq_imp_iff₂]
@[deprecated flatMap_eq_nil_iff (since := "2024-09-05")] abbrev bind_eq_nil := @flatMap_eq_nil_iff
@[deprecated bind_eq_nil_iff (since := "2024-09-05")] abbrev bind_eq_nil := @bind_eq_nil_iff
theorem forall_mem_flatMap {p : β Prop} {l : List α} {f : α List β} :
( (x) (_ : x l.flatMap f), p x) (a) (_ : a l) (b) (_ : b f a), p b := by
simp only [mem_flatMap, forall_exists_index, and_imp]
theorem forall_mem_bind {p : β Prop} {l : List α} {f : α List β} :
( (x) (_ : x l.bind f), p x) (a) (_ : a l) (b) (_ : b f a), p b := by
simp only [mem_bind, forall_exists_index, and_imp]
constructor <;> (intros; solve_by_elim)
theorem flatMap_singleton (f : α List β) (x : α) : [x].flatMap f = f x :=
theorem bind_singleton (f : α List β) (x : α) : [x].bind f = f x :=
append_nil (f x)
@[simp] theorem flatMap_singleton' (l : List α) : (l.flatMap fun x => [x]) = l := by
@[simp] theorem bind_singleton' (l : List α) : (l.bind fun x => [x]) = l := by
induction l <;> simp [*]
theorem head?_flatMap {l : List α} {f : α List β} :
(l.flatMap f).head? = l.findSome? fun a => (f a).head? := by
theorem head?_bind {l : List α} {f : α List β} :
(l.bind f).head? = l.findSome? fun a => (f a).head? := by
induction l with
| nil => rfl
| cons =>
simp only [findSome?_cons]
split <;> simp_all
@[simp] theorem flatMap_append (xs ys : List α) (f : α List β) :
(xs ++ ys).flatMap f = xs.flatMap f ++ ys.flatMap f := by
induction xs; {rfl}; simp_all [flatMap_cons, append_assoc]
@[simp] theorem bind_append (xs ys : List α) (f : α List β) :
(xs ++ ys).bind f = xs.bind f ++ ys.bind f := by
induction xs; {rfl}; simp_all [bind_cons, append_assoc]
@[deprecated flatMap_append (since := "2024-07-24")] abbrev append_bind := @flatMap_append
@[deprecated bind_append (since := "2024-07-24")] abbrev append_bind := @bind_append
theorem flatMap_assoc {α β} (l : List α) (f : α List β) (g : β List γ) :
(l.flatMap f).flatMap g = l.flatMap fun x => (f x).flatMap g := by
theorem bind_assoc {α β} (l : List α) (f : α List β) (g : β List γ) :
(l.bind f).bind g = l.bind fun x => (f x).bind g := by
induction l <;> simp [*]
theorem map_flatMap (f : β γ) (g : α List β) :
l : List α, (l.flatMap g).map f = l.flatMap fun a => (g a).map f
theorem map_bind (f : β γ) (g : α List β) :
l : List α, (l.bind g).map f = l.bind fun a => (g a).map f
| [] => rfl
| a::l => by simp only [flatMap_cons, map_append, map_flatMap _ _ l]
| a::l => by simp only [bind_cons, map_append, map_bind _ _ l]
theorem flatMap_map (f : α β) (g : β List γ) (l : List α) :
(map f l).flatMap g = l.flatMap (fun a => g (f a)) := by
induction l <;> simp [flatMap_cons, *]
theorem bind_map (f : α β) (g : β List γ) (l : List α) :
(map f l).bind g = l.bind (fun a => g (f a)) := by
induction l <;> simp [bind_cons, *]
theorem map_eq_flatMap {α β} (f : α β) (l : List α) : map f l = l.flatMap fun x => [f x] := by
theorem map_eq_bind {α β} (f : α β) (l : List α) : map f l = l.bind fun x => [f x] := by
simp only [ map_singleton]
rw [ flatMap_singleton' l, map_flatMap, flatMap_singleton']
rw [ bind_singleton' l, map_bind, bind_singleton']
theorem filterMap_flatMap {β γ} (l : List α) (g : α List β) (f : β Option γ) :
(l.flatMap g).filterMap f = l.flatMap fun a => (g a).filterMap f := by
theorem filterMap_bind {β γ} (l : List α) (g : α List β) (f : β Option γ) :
(l.bind g).filterMap f = l.bind fun a => (g a).filterMap f := by
induction l <;> simp [*]
theorem filter_flatMap (l : List α) (g : α List β) (f : β Bool) :
(l.flatMap g).filter f = l.flatMap fun a => (g a).filter f := by
theorem filter_bind (l : List α) (g : α List β) (f : β Bool) :
(l.bind g).filter f = l.bind fun a => (g a).filter f := by
induction l <;> simp [*]
theorem flatMap_eq_foldl (f : α List β) (l : List α) :
l.flatMap f = l.foldl (fun acc a => acc ++ f a) [] := by
suffices l', l' ++ l.flatMap f = l.foldl (fun acc a => acc ++ f a) l' by simpa using this []
theorem bind_eq_foldl (f : α List β) (l : List α) :
l.bind f = l.foldl (fun acc a => acc ++ f a) [] := by
suffices l', l' ++ l.bind f = l.foldl (fun acc a => acc ++ f a) l' by simpa using this []
intro l'
induction l generalizing l'
· simp
· next ih => rw [flatMap_cons, append_assoc, ih, foldl_cons]
· next ih => rw [bind_cons, append_assoc, ih, foldl_cons]
/-! ### replicate -/
@@ -2405,21 +2387,11 @@ theorem map_eq_replicate_iff {l : List α} {f : α → β} {b : β} :
@[simp] theorem map_const (l : List α) (b : β) : map (Function.const α b) l = replicate l.length b :=
map_eq_replicate_iff.mpr fun _ _ => rfl
@[simp] theorem map_const_fun (x : β) : map (Function.const α x) = (replicate ·.length x) := by
funext l
simp
/-- Variant of `map_const` using a lambda rather than `Function.const`. -/
-- This can not be a `@[simp]` lemma because it would fire on every `List.map`.
theorem map_const' (l : List α) (b : β) : map (fun _ => b) l = replicate l.length b :=
map_const l b
@[simp] theorem set_replicate_self : (replicate n a).set i a = replicate n a := by
apply ext_getElem
· simp
· intro i h₁ h₂
simp [getElem_set]
@[simp] theorem append_replicate_replicate : replicate n a ++ replicate m a = replicate (n + m) a := by
rw [eq_replicate_iff]
constructor
@@ -2479,23 +2451,23 @@ theorem filterMap_replicate_of_some {f : α → Option β} (h : f a = some b) :
(replicate n a).filterMap f = [] := by
simp [filterMap_replicate, h]
@[simp] theorem flatten_replicate_nil : (replicate n ([] : List α)).flatten = [] := by
@[simp] theorem join_replicate_nil : (replicate n ([] : List α)).join = [] := by
induction n <;> simp_all [replicate_succ]
@[simp] theorem flatten_replicate_singleton : (replicate n [a]).flatten = replicate n a := by
@[simp] theorem join_replicate_singleton : (replicate n [a]).join = replicate n a := by
induction n <;> simp_all [replicate_succ]
@[simp] theorem flatten_replicate_replicate : (replicate n (replicate m a)).flatten = replicate (n * m) a := by
@[simp] theorem join_replicate_replicate : (replicate n (replicate m a)).join = replicate (n * m) a := by
induction n with
| zero => simp
| succ n ih =>
simp only [replicate_succ, flatten_cons, ih, append_replicate_replicate, replicate_inj, or_true,
simp only [replicate_succ, join_cons, ih, append_replicate_replicate, replicate_inj, or_true,
and_true, add_one_mul, Nat.add_comm]
theorem flatMap_replicate {β} (f : α List β) : (replicate n a).flatMap f = (replicate n (f a)).flatten := by
theorem bind_replicate {β} (f : α List β) : (replicate n a).bind f = (replicate n (f a)).join := by
induction n with
| zero => simp
| succ n ih => simp only [replicate_succ, flatMap_cons, ih, flatten_cons]
| succ n ih => simp only [replicate_succ, bind_cons, ih, join_cons]
@[simp] theorem isEmpty_replicate : (replicate n a).isEmpty = decide (n = 0) := by
cases n <;> simp [replicate_succ]
@@ -2670,20 +2642,20 @@ theorem reverse_eq_concat {xs ys : List α} {a : α} :
xs.reverse = ys ++ [a] xs = a :: ys.reverse := by
rw [reverse_eq_iff, reverse_concat]
/-- Reversing a flatten is the same as reversing the order of parts and reversing all parts. -/
theorem reverse_flatten (L : List (List α)) :
L.flatten.reverse = (L.map reverse).reverse.flatten := by
/-- Reversing a join is the same as reversing the order of parts and reversing all parts. -/
theorem reverse_join (L : List (List α)) :
L.join.reverse = (L.map reverse).reverse.join := by
induction L <;> simp_all
/-- Flattening a reverse is the same as reversing all parts and reversing the flattened result. -/
theorem flatten_reverse (L : List (List α)) :
L.reverse.flatten = (L.map reverse).flatten.reverse := by
/-- Joining a reverse is the same as reversing all parts and reversing the joined result. -/
theorem join_reverse (L : List (List α)) :
L.reverse.join = (L.map reverse).join.reverse := by
induction L <;> simp_all
theorem reverse_flatMap {β} (l : List α) (f : α List β) : (l.flatMap f).reverse = l.reverse.flatMap (reverse f) := by
theorem reverse_bind {β} (l : List α) (f : α List β) : (l.bind f).reverse = l.reverse.bind (reverse f) := by
induction l <;> simp_all
theorem flatMap_reverse {β} (l : List α) (f : α List β) : (l.reverse.flatMap f) = (l.flatMap (reverse f)).reverse := by
theorem bind_reverse {β} (l : List α) (f : α List β) : (l.reverse.bind f) = (l.bind (reverse f)).reverse := by
induction l <;> simp_all
@[simp] theorem reverseAux_eq (as bs : List α) : reverseAux as bs = reverse as ++ bs :=
@@ -2703,7 +2675,7 @@ theorem flatMap_reverse {β} (l : List α) (f : α → List β) : (l.reverse.fla
@[simp] theorem reverse_replicate (n) (a : α) : reverse (replicate n a) = replicate n a :=
eq_replicate_iff.2
by rw [length_reverse, length_replicate],
fun _ h => eq_of_mem_replicate (mem_reverse.1 h)
fun b h => eq_of_mem_replicate (mem_reverse.1 h)
/-! #### Further results about `getLast` and `getLast?` -/
@@ -2791,15 +2763,15 @@ theorem getLast_filterMap_of_eq_some {f : α → Option β} {l : List α} {w : l
rw [head_filterMap_of_eq_some (by simp_all)]
simp_all
theorem getLast?_flatMap {L : List α} {f : α List β} :
(L.flatMap f).getLast? = L.reverse.findSome? fun a => (f a).getLast? := by
simp only [ head?_reverse, reverse_flatMap]
rw [head?_flatMap]
theorem getLast?_bind {L : List α} {f : α List β} :
(L.bind f).getLast? = L.reverse.findSome? fun a => (f a).getLast? := by
simp only [ head?_reverse, reverse_bind]
rw [head?_bind]
rfl
theorem getLast?_flatten {L : List (List α)} :
(flatten L).getLast? = L.reverse.findSome? fun l => l.getLast? := by
simp [ flatMap_id, getLast?_flatMap]
theorem getLast?_join {L : List (List α)} :
(join L).getLast? = L.reverse.findSome? fun l => l.getLast? := by
simp [ bind_id, getLast?_bind]
theorem getLast?_replicate (a : α) (n : Nat) : (replicate n a).getLast? = if n = 0 then none else some a := by
simp only [ head?_reverse, reverse_replicate, head?_replicate]
@@ -2908,7 +2880,7 @@ theorem head?_dropLast (xs : List α) : xs.dropLast.head? = if 1 < xs.length the
theorem getLast_dropLast {xs : List α} (h) :
xs.dropLast.getLast h =
xs[xs.length - 2]'(match xs, h with | (_ :: _ :: _), _ => Nat.lt_trans (Nat.lt_add_one _) (Nat.lt_add_one _)) := by
xs[xs.length - 2]'(match xs, h with | (a :: b :: xs), _ => Nat.lt_trans (Nat.lt_add_one _) (Nat.lt_add_one _)) := by
rw [getLast_eq_getElem, getElem_dropLast]
congr 1
simp; rfl
@@ -2932,8 +2904,8 @@ theorem dropLast_cons_of_ne_nil {α : Type u} {x : α}
theorem dropLast_concat_getLast : {l : List α} (h : l []), dropLast l ++ [getLast l h] = l
| [], h => absurd rfl h
| [_], _ => rfl
| _ :: b :: l, _ => by
| [a], h => rfl
| a :: b :: l, h => by
rw [dropLast_cons₂, cons_append, getLast_cons (cons_ne_nil _ _)]
congr
exact dropLast_concat_getLast (cons_ne_nil b l)
@@ -3298,22 +3270,18 @@ theorem all_eq_not_any_not (l : List α) (p : α → Bool) : l.all p = !l.any (!
| nil => rfl
| cons h t ih => simp_all [Bool.and_assoc]
@[simp] theorem any_flatten {l : List (List α)} : l.flatten.any f = l.any (any · f) := by
@[simp] theorem any_join {l : List (List α)} : l.join.any f = l.any (any · f) := by
induction l <;> simp_all
@[deprecated any_flatten (since := "2024-10-14")] abbrev any_join := @any_flatten
@[simp] theorem all_flatten {l : List (List α)} : l.flatten.all f = l.all (all · f) := by
@[simp] theorem all_join {l : List (List α)} : l.join.all f = l.all (all · f) := by
induction l <;> simp_all
@[deprecated all_flatten (since := "2024-10-14")] abbrev all_join := @all_flatten
@[simp] theorem any_flatMap {l : List α} {f : α List β} :
(l.flatMap f).any p = l.any fun a => (f a).any p := by
@[simp] theorem any_bind {l : List α} {f : α List β} :
(l.bind f).any p = l.any fun a => (f a).any p := by
induction l <;> simp_all
@[simp] theorem all_flatMap {l : List α} {f : α List β} :
(l.flatMap f).all p = l.all fun a => (f a).all p := by
@[simp] theorem all_bind {l : List α} {f : α List β} :
(l.bind f).all p = l.all fun a => (f a).all p := by
induction l <;> simp_all
@[simp] theorem any_reverse {l : List α} : l.reverse.any f = l.any f := by
@@ -3328,7 +3296,7 @@ theorem all_eq_not_any_not (l : List α) (p : α → Bool) : l.all p = !l.any (!
@[simp] theorem all_replicate {n : Nat} {a : α} :
(replicate n a).all f = if n = 0 then true else f a := by
cases n <;> simp +contextual [replicate_succ]
cases n <;> simp (config := {contextual := true}) [replicate_succ]
@[simp] theorem any_insert [BEq α] [LawfulBEq α] {l : List α} {a : α} :
(l.insert a).any f = (f a || l.any f) := by
@@ -3338,72 +3306,4 @@ 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]
/-! ### Deprecations -/
@[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
@[deprecated forall_mem_flatten (since := "2024-10-14")] abbrev forall_mem_join := @forall_mem_flatten
@[deprecated flatten_eq_flatMap (since := "2024-10-14")] abbrev join_eq_bind := @flatten_eq_flatMap
@[deprecated head?_flatten (since := "2024-10-14")] abbrev head?_join := @head?_flatten
@[deprecated foldl_flatten (since := "2024-10-14")] abbrev foldl_join := @foldl_flatten
@[deprecated foldr_flatten (since := "2024-10-14")] abbrev foldr_join := @foldr_flatten
@[deprecated map_flatten (since := "2024-10-14")] abbrev map_join := @map_flatten
@[deprecated filterMap_flatten (since := "2024-10-14")] abbrev filterMap_join := @filterMap_flatten
@[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
@[deprecated flatten_replicate_singleton (since := "2024-10-14")] abbrev join_replicate_singleton := @flatten_replicate_singleton
@[deprecated flatten_replicate_replicate (since := "2024-10-14")] abbrev join_replicate_replicate := @flatten_replicate_replicate
@[deprecated reverse_flatten (since := "2024-10-14")] abbrev reverse_join := @reverse_flatten
@[deprecated flatten_reverse (since := "2024-10-14")] abbrev join_reverse := @flatten_reverse
@[deprecated getLast?_flatten (since := "2024-10-14")] abbrev getLast?_join := @getLast?_flatten
@[deprecated flatten_eq_flatMap (since := "2024-10-16")] abbrev flatten_eq_bind := @flatten_eq_flatMap
@[deprecated flatMap_def (since := "2024-10-16")] abbrev bind_def := @flatMap_def
@[deprecated flatMap_id (since := "2024-10-16")] abbrev bind_id := @flatMap_id
@[deprecated mem_flatMap (since := "2024-10-16")] abbrev mem_bind := @mem_flatMap
@[deprecated exists_of_mem_flatMap (since := "2024-10-16")] abbrev exists_of_mem_bind := @exists_of_mem_flatMap
@[deprecated mem_flatMap_of_mem (since := "2024-10-16")] abbrev mem_bind_of_mem := @mem_flatMap_of_mem
@[deprecated flatMap_eq_nil_iff (since := "2024-10-16")] abbrev bind_eq_nil_iff := @flatMap_eq_nil_iff
@[deprecated forall_mem_flatMap (since := "2024-10-16")] abbrev forall_mem_bind := @forall_mem_flatMap
@[deprecated flatMap_singleton (since := "2024-10-16")] abbrev bind_singleton := @flatMap_singleton
@[deprecated flatMap_singleton' (since := "2024-10-16")] abbrev bind_singleton' := @flatMap_singleton'
@[deprecated head?_flatMap (since := "2024-10-16")] abbrev head_bind := @head?_flatMap
@[deprecated flatMap_append (since := "2024-10-16")] abbrev bind_append := @flatMap_append
@[deprecated flatMap_assoc (since := "2024-10-16")] abbrev bind_assoc := @flatMap_assoc
@[deprecated map_flatMap (since := "2024-10-16")] abbrev map_bind := @map_flatMap
@[deprecated flatMap_map (since := "2024-10-16")] abbrev bind_map := @flatMap_map
@[deprecated map_eq_flatMap (since := "2024-10-16")] abbrev map_eq_bind := @map_eq_flatMap
@[deprecated filterMap_flatMap (since := "2024-10-16")] abbrev filterMap_bind := @filterMap_flatMap
@[deprecated filter_flatMap (since := "2024-10-16")] abbrev filter_bind := @filter_flatMap
@[deprecated flatMap_eq_foldl (since := "2024-10-16")] abbrev bind_eq_foldl := @flatMap_eq_foldl
@[deprecated flatMap_replicate (since := "2024-10-16")] abbrev bind_replicate := @flatMap_replicate
@[deprecated reverse_flatMap (since := "2024-10-16")] abbrev reverse_bind := @reverse_flatMap
@[deprecated flatMap_reverse (since := "2024-10-16")] abbrev bind_reverse := @flatMap_reverse
@[deprecated getLast?_flatMap (since := "2024-10-16")] abbrev getLast?_bind := @getLast?_flatMap
@[deprecated any_flatMap (since := "2024-10-16")] abbrev any_bind := @any_flatMap
@[deprecated all_flatMap (since := "2024-10-16")] abbrev all_bind := @all_flatMap
end List

View File

@@ -1,408 +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, Mario Carneiro
-/
prelude
import Init.Data.Array.Lemmas
import Init.Data.List.Nat.Range
import Init.Data.List.OfFn
import Init.Data.Fin.Lemmas
import Init.Data.Option.Attach
namespace List
/-! ## Operations using indexes -/
/-! ### mapIdx -/
/--
Given a list `as = [a₀, a₁, ...]` function `f : Fin as.length → α → β`, returns the list
`[f 0 a₀, f 1 a₁, ...]`.
-/
@[inline] def mapFinIdx (as : List α) (f : Fin as.length α β) : List β := go as #[] (by simp) where
/-- Auxiliary for `mapFinIdx`:
`mapFinIdx.go [a₀, a₁, ...] acc = acc.toList ++ [f 0 a₀, f 1 a₁, ...]` -/
@[specialize] go : (bs : List α) (acc : Array β) bs.length + acc.size = as.length List β
| [], acc, h => acc.toList
| a :: as, acc, h =>
go as (acc.push (f acc.size, by simp at h; omega a)) (by simp at h ; omega)
/--
Given a function `f : Nat → α → β` and `as : List α`, `as = [a₀, a₁, ...]`, returns the list
`[f 0 a₀, f 1 a₁, ...]`.
-/
@[inline] def mapIdx (f : Nat α β) (as : List α) : List β := go as #[] where
/-- Auxiliary for `mapIdx`:
`mapIdx.go [a₀, a₁, ...] acc = acc.toList ++ [f acc.size a₀, f (acc.size + 1) a₁, ...]` -/
@[specialize] go : List α Array β List β
| [], acc => acc.toList
| a :: as, acc => go as (acc.push (f acc.size a))
/-! ### mapFinIdx -/
@[simp]
theorem mapFinIdx_nil {f : Fin 0 α β} : mapFinIdx [] f = [] :=
rfl
@[simp] theorem length_mapFinIdx_go :
(mapFinIdx.go as f bs acc h).length = as.length := by
induction bs generalizing acc with
| nil => simpa using h
| cons _ _ ih => simp [mapFinIdx.go, ih]
@[simp] theorem length_mapFinIdx {as : List α} {f : Fin as.length α β} :
(as.mapFinIdx f).length = as.length := by
simp [mapFinIdx, length_mapFinIdx_go]
theorem getElem_mapFinIdx_go {as : List α} {f : Fin as.length α β} {i : Nat} {h} {w} :
(mapFinIdx.go as f bs acc h)[i] =
if w' : i < acc.size then acc[i] else f i, by simp at w; omega (bs[i - acc.size]'(by simp at w; omega)) := by
induction bs generalizing acc with
| nil =>
simp only [length_mapFinIdx_go, length_nil, Nat.zero_add] at w h
simp only [mapFinIdx.go, Array.getElem_toList]
rw [dif_pos]
| cons _ _ ih =>
simp [mapFinIdx.go]
rw [ih]
simp
split <;> rename_i h₁ <;> split <;> rename_i h₂
· rw [Array.getElem_push_lt]
· have h₃ : i = acc.size := by omega
subst h₃
simp
· omega
· have h₃ : i - acc.size = (i - (acc.size + 1)) + 1 := by omega
simp [h₃]
@[simp] theorem getElem_mapFinIdx {as : List α} {f : Fin as.length α β} {i : Nat} {h} :
(as.mapFinIdx f)[i] = f i, by simp at h; omega (as[i]'(by simp at h; omega)) := by
simp [mapFinIdx, getElem_mapFinIdx_go]
theorem mapFinIdx_eq_ofFn {as : List α} {f : Fin as.length α β} :
as.mapFinIdx f = List.ofFn fun i : Fin as.length => f i as[i] := by
apply ext_getElem <;> simp
@[simp] theorem getElem?_mapFinIdx {l : List α} {f : Fin l.length α β} {i : Nat} :
(l.mapFinIdx f)[i]? = l[i]?.pbind fun x m => f i, by simp [getElem?_eq_some] at m; exact m.1 x := by
simp only [getElem?_eq, length_mapFinIdx, getElem_mapFinIdx]
split <;> simp
@[simp]
theorem mapFinIdx_cons {l : List α} {a : α} {f : Fin (l.length + 1) α β} :
mapFinIdx (a :: l) f = f 0 a :: mapFinIdx l (fun i => f i.succ) := by
apply ext_getElem
· simp
· rintro (_|i) h₁ h₂ <;> simp
theorem mapFinIdx_append {K L : List α} {f : Fin (K ++ L).length α β} :
(K ++ L).mapFinIdx f =
K.mapFinIdx (fun i => f (i.castLE (by simp))) ++ L.mapFinIdx (fun i => f ((i.natAdd K.length).cast (by simp))) := by
apply ext_getElem
· simp
· intro i h₁ h₂
rw [getElem_append]
simp only [getElem_mapFinIdx, length_mapFinIdx]
split <;> rename_i h
· rw [getElem_append_left]
congr
· simp only [Nat.not_lt] at h
rw [getElem_append_right h]
congr
simp
omega
@[simp] theorem mapFinIdx_concat {l : List α} {e : α} {f : Fin (l ++ [e]).length α β}:
(l ++ [e]).mapFinIdx f = l.mapFinIdx (fun i => f (i.castLE (by simp))) ++ [f l.length, by simp e] := by
simp [mapFinIdx_append]
congr
theorem mapFinIdx_singleton {a : α} {f : Fin 1 α β} :
[a].mapFinIdx f = [f 0, by simp a] := by
simp
theorem mapFinIdx_eq_enum_map {l : List α} {f : Fin l.length α β} :
l.mapFinIdx f = l.enum.attach.map
fun i, x, m => f i, by rw [mk_mem_enum_iff_getElem?, getElem?_eq_some] at m; exact m.1 x := by
apply ext_getElem <;> simp
@[simp]
theorem mapFinIdx_eq_nil_iff {l : List α} {f : Fin l.length α β} :
l.mapFinIdx f = [] l = [] := by
rw [mapFinIdx_eq_enum_map, map_eq_nil_iff, attach_eq_nil_iff, enum_eq_nil_iff]
theorem mapFinIdx_ne_nil_iff {l : List α} {f : Fin l.length α β} :
l.mapFinIdx f [] l [] := by
simp
theorem exists_of_mem_mapFinIdx {b : β} {l : List α} {f : Fin l.length α β}
(h : b l.mapFinIdx f) : (i : Fin l.length), f i l[i] = b := by
rw [mapFinIdx_eq_enum_map] at h
replace h := exists_of_mem_map h
simp only [mem_attach, true_and, Subtype.exists, Prod.exists, mk_mem_enum_iff_getElem?] at h
obtain i, b, h, rfl := h
rw [getElem?_eq_some_iff] at h
obtain h', rfl := h
exact i, h', rfl
@[simp] theorem mem_mapFinIdx {b : β} {l : List α} {f : Fin l.length α β} :
b l.mapFinIdx f (i : Fin l.length), f i l[i] = b := by
constructor
· intro h
exact exists_of_mem_mapFinIdx h
· rintro i, h, rfl
rw [mem_iff_getElem]
exact i, by simp
theorem mapFinIdx_eq_cons_iff {l : List α} {b : β} {f : Fin l.length α β} :
l.mapFinIdx f = b :: l₂
(a : α) (l₁ : List α) (h : l = a :: l₁),
f 0, by simp [h] a = b l₁.mapFinIdx (fun i => f (i.succ.cast (by simp [h]))) = l₂ := by
cases l with
| nil => simp
| cons x l' =>
simp only [mapFinIdx_cons, cons.injEq, length_cons, Fin.zero_eta, Fin.cast_succ_eq,
exists_and_left]
constructor
· rintro rfl, rfl
refine x, rfl, l', by simp
· rintro a, rfl, h, _, rfl, rfl, h
exact rfl, h
theorem mapFinIdx_eq_cons_iff' {l : List α} {b : β} {f : Fin l.length α β} :
l.mapFinIdx f = b :: l₂
l.head?.pbind (fun x m => (f 0, by cases l <;> simp_all x)) = some b
l.tail?.attach.map (fun t, m => t.mapFinIdx fun i => f (i.succ.cast (by cases l <;> simp_all))) = some l₂ := by
cases l <;> simp
theorem mapFinIdx_eq_iff {l : List α} {f : Fin l.length α β} :
l.mapFinIdx f = l' h : l'.length = l.length, (i : Nat) (h : i < l.length), l'[i] = f i, h l[i] := by
constructor
· rintro rfl
simp
· rintro h, w
apply ext_getElem <;> simp_all
theorem mapFinIdx_eq_mapFinIdx_iff {l : List α} {f g : Fin l.length α β} :
l.mapFinIdx f = l.mapFinIdx g (i : Fin l.length), f i l[i] = g i l[i] := by
rw [eq_comm, mapFinIdx_eq_iff]
simp [Fin.forall_iff]
@[simp] theorem mapFinIdx_mapFinIdx {l : List α} {f : Fin l.length α β} {g : Fin _ β γ} :
(l.mapFinIdx f).mapFinIdx g = l.mapFinIdx (fun i => g (i.cast (by simp)) f i) := by
simp [mapFinIdx_eq_iff]
theorem mapFinIdx_eq_replicate_iff {l : List α} {f : Fin l.length α β} {b : β} :
l.mapFinIdx f = replicate l.length b (i : Fin l.length), f i l[i] = b := by
simp [eq_replicate_iff, length_mapFinIdx, mem_mapFinIdx, forall_exists_index, true_and]
@[simp] theorem mapFinIdx_reverse {l : List α} {f : Fin l.reverse.length α β} :
l.reverse.mapFinIdx f = (l.mapFinIdx (fun i => f l.length - 1 - i, by simp; omega)).reverse := by
simp [mapFinIdx_eq_iff]
intro i h
congr
omega
/-! ### mapIdx -/
@[simp]
theorem mapIdx_nil {f : Nat α β} : mapIdx f [] = [] :=
rfl
theorem mapIdx_go_length {arr : Array β} :
length (mapIdx.go f l arr) = length l + arr.size := by
induction l generalizing arr with
| nil => simp only [mapIdx.go, length_nil, Nat.zero_add]
| cons _ _ ih =>
simp only [mapIdx.go, ih, Array.size_push, Nat.add_succ, length_cons, Nat.add_comm]
theorem length_mapIdx_go : {l : List α} {arr : Array β},
(mapIdx.go f l arr).length = l.length + arr.size
| [], _ => by simp [mapIdx.go]
| a :: l, _ => by
simp only [mapIdx.go, length_cons]
rw [length_mapIdx_go]
simp
omega
@[simp] theorem length_mapIdx {l : List α} : (l.mapIdx f).length = l.length := by
simp [mapIdx, length_mapIdx_go]
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?_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_eq_getElem_toList]
simp only [Array.push_toList]
rw [getElem_append_left, Array.getElem_eq_getElem_toList]
· have : i = arr.size := by omega
simp_all
· omega
· have : i - arr.size = i - (arr.size + 1) + 1 := by omega
simp_all
@[simp] theorem getElem?_mapIdx {l : List α} {i : Nat} :
(l.mapIdx f)[i]? = Option.map (f i) l[i]? := by
simp [mapIdx, getElem?_mapIdx_go]
@[simp] theorem getElem_mapIdx {l : List α} {f : Nat α β} {i : Nat} {h : i < (l.mapIdx f).length} :
(l.mapIdx f)[i] = f i (l[i]'(by simpa using h)) := by
apply Option.some_inj.mp
rw [ getElem?_eq_getElem, getElem?_mapIdx, getElem?_eq_getElem (by simpa using h)]
simp
@[simp] theorem mapFinIdx_eq_mapIdx {l : List α} {f : Fin l.length α β} {g : Nat α β}
(h : (i : Fin l.length), f i l[i] = g i l[i]) :
l.mapFinIdx f = l.mapIdx g := by
simp_all [mapFinIdx_eq_iff]
theorem mapIdx_eq_mapFinIdx {l : List α} {f : Nat α β} :
l.mapIdx f = l.mapFinIdx (fun i => f i) := by
simp [mapFinIdx_eq_mapIdx]
theorem mapIdx_eq_enum_map {l : List α} :
l.mapIdx f = l.enum.map (Function.uncurry f) := by
ext1 i
simp only [getElem?_mapIdx, Option.map, getElem?_map, getElem?_enum]
split <;> simp
@[simp]
theorem mapIdx_cons {l : List α} {a : α} :
mapIdx f (a :: l) = f 0 a :: mapIdx (fun i => f (i + 1)) l := by
simp [mapIdx_eq_enum_map, enum_eq_zip_range, map_uncurry_zip_eq_zipWith,
range_succ_eq_map, zipWith_map_left]
theorem mapIdx_append {K L : List α} :
(K ++ L).mapIdx f = K.mapIdx f ++ L.mapIdx fun i => f (i + K.length) := by
induction K generalizing f with
| nil => rfl
| cons _ _ ih => simp [ih (f := fun i => f (i + 1)), Nat.add_assoc]
@[simp] theorem mapIdx_concat {l : List α} {e : α} :
mapIdx f (l ++ [e]) = mapIdx f l ++ [f l.length e] := by
simp [mapIdx_append]
theorem mapIdx_singleton {a : α} : mapIdx f [a] = [f 0 a] := by
simp
@[simp]
theorem mapIdx_eq_nil_iff {l : List α} : List.mapIdx f l = [] l = [] := by
rw [List.mapIdx_eq_enum_map, List.map_eq_nil_iff, List.enum_eq_nil_iff]
theorem mapIdx_ne_nil_iff {l : List α} :
List.mapIdx f l [] l [] := by
simp
theorem exists_of_mem_mapIdx {b : β} {l : List α}
(h : b mapIdx f l) : (i : Nat) (h : i < l.length), f i l[i] = b := by
rw [mapIdx_eq_mapFinIdx] at h
simpa [Fin.exists_iff] using exists_of_mem_mapFinIdx h
@[simp] theorem mem_mapIdx {b : β} {l : List α} :
b mapIdx f l (i : Nat) (h : i < l.length), f i l[i] = b := by
constructor
· intro h
exact exists_of_mem_mapIdx h
· rintro i, h, rfl
rw [mem_iff_getElem]
exact i, by simpa using h, by simp
theorem mapIdx_eq_cons_iff {l : List α} {b : β} :
mapIdx f l = b :: l₂
(a : α) (l₁ : List α), l = a :: l₁ f 0 a = b mapIdx (fun i => f (i + 1)) l₁ = l₂ := by
cases l <;> simp [and_assoc]
theorem mapIdx_eq_cons_iff' {l : List α} {b : β} :
mapIdx f l = b :: l₂
l.head?.map (f 0) = some b l.tail?.map (mapIdx fun i => f (i + 1)) = some l₂ := by
cases l <;> simp
theorem mapIdx_eq_iff {l : List α} : mapIdx f l = l' i : Nat, l'[i]? = l[i]?.map (f i) := by
constructor
· intro w i
simpa using congrArg (fun l => l[i]?) w.symm
· intro w
ext1 i
simp [w]
theorem mapIdx_eq_mapIdx_iff {l : List α} :
mapIdx f l = mapIdx g l i : Nat, (h : i < l.length) f i l[i] = g i l[i] := by
constructor
· intro w i h
simpa [h] using congrArg (fun l => l[i]?) w
· intro w
apply ext_getElem
· simp
· intro i h₁ h₂
simp [w]
@[simp] theorem mapIdx_set {l : List α} {i : Nat} {a : α} :
(l.set i a).mapIdx f = (l.mapIdx f).set i (f i a) := by
simp only [mapIdx_eq_iff, getElem?_set, length_mapIdx, getElem?_mapIdx]
intro i
split
· split <;> simp_all
· rfl
@[simp] theorem head_mapIdx {l : List α} {f : Nat α β} {w : mapIdx f l []} :
(mapIdx f l).head w = f 0 (l.head (by simpa using w)) := by
cases l with
| nil => simp at w
| cons _ _ => simp
@[simp] theorem head?_mapIdx {l : List α} {f : Nat α β} : (mapIdx f l).head? = l.head?.map (f 0) := by
cases l <;> simp
@[simp] theorem getLast_mapIdx {l : List α} {f : Nat α β} {h} :
(mapIdx f l).getLast h = f (l.length - 1) (l.getLast (by simpa using h)) := by
cases l with
| nil => simp at h
| cons _ _ =>
simp only [ getElem_cons_length _ _ _ rfl]
simp only [mapIdx_cons]
simp only [ getElem_cons_length _ _ _ rfl]
simp only [ mapIdx_cons, getElem_mapIdx]
simp
@[simp] theorem getLast?_mapIdx {l : List α} {f : Nat α β} :
(mapIdx f l).getLast? = (getLast? l).map (f (l.length - 1)) := by
cases l
· simp
· rw [getLast?_eq_getLast, getLast?_eq_getLast, getLast_mapIdx] <;> simp
@[simp] theorem mapIdx_mapIdx {l : List α} {f : Nat α β} {g : Nat β γ} :
(l.mapIdx f).mapIdx g = l.mapIdx (fun i => g i f i) := by
simp [mapIdx_eq_iff]
theorem mapIdx_eq_replicate_iff {l : List α} {f : Nat α β} {b : β} :
mapIdx f l = replicate l.length b (i : Nat) (h : i < l.length), f i l[i] = b := by
simp only [eq_replicate_iff, length_mapIdx, mem_mapIdx, forall_exists_index, true_and]
constructor
· intro w i h
apply w _ _ _ rfl
· rintro w _ i h rfl
exact w i h
@[simp] theorem mapIdx_reverse {l : List α} {f : Nat α β} :
l.reverse.mapIdx f = (mapIdx (fun i => f (l.length - 1 - i)) l).reverse := by
simp [mapIdx_eq_iff]
intro i
by_cases h : i < l.length
· simp [getElem?_reverse, h]
congr
omega
· simp at h
rw [getElem?_eq_none (by simp [h]), getElem?_eq_none (by simp [h])]
simp
end List

View File

@@ -7,7 +7,7 @@ prelude
import Init.Data.List.Lemmas
/-!
# Lemmas about `List.min?` and `List.max?.
# Lemmas about `List.minimum?` and `List.maximum?.
-/
namespace List
@@ -16,32 +16,24 @@ open Nat
/-! ## Minima and maxima -/
/-! ### min? -/
/-! ### minimum? -/
@[simp] theorem min?_nil [Min α] : ([] : List α).min? = none := rfl
@[simp] theorem minimum?_nil [Min α] : ([] : List α).minimum? = none := rfl
-- We don't put `@[simp]` on `min?_cons'`,
-- We don't put `@[simp]` on `minimum?_cons`,
-- because the definition in terms of `foldl` is not useful for proofs.
theorem min?_cons' [Min α] {xs : List α} : (x :: xs).min? = foldl min x xs := rfl
theorem minimum?_cons [Min α] {xs : List α} : (x :: xs).minimum? = foldl min x xs := rfl
@[simp] theorem min?_cons [Min α] [Std.Associative (min : α α α)] {xs : List α} :
(x :: xs).min? = some (xs.min?.elim x (min x)) := by
cases xs <;> simp [min?_cons', foldl_assoc]
@[simp] theorem minimum?_eq_none_iff {xs : List α} [Min α] : xs.minimum? = none xs = [] := by
cases xs <;> simp [minimum?]
@[simp] theorem min?_eq_none_iff {xs : List α} [Min α] : xs.min? = none xs = [] := by
cases xs <;> simp [min?]
theorem isSome_min?_of_mem {l : List α} [Min α] {a : α} (h : a l) :
l.min?.isSome := by
cases l <;> simp_all [List.min?_cons']
theorem min?_mem [Min α] (min_eq_or : a b : α, min a b = a min a b = b) :
{xs : List α} xs.min? = some a a xs := by
theorem minimum?_mem [Min α] (min_eq_or : a b : α, min a b = a min a b = b) :
{xs : List α} xs.minimum? = some a a xs := by
intro xs
match xs with
| nil => simp
| x :: xs =>
simp only [min?_cons', Option.some.injEq, List.mem_cons]
simp only [minimum?_cons, Option.some.injEq, List.mem_cons]
intro eq
induction xs generalizing x with
| nil =>
@@ -57,12 +49,12 @@ theorem min?_mem [Min α] (min_eq_or : ∀ a b : α, min a b = a min a b = b
-- See also `Init.Data.List.Nat.Basic` for specialisations of the next two results to `Nat`.
theorem le_min?_iff [Min α] [LE α]
theorem le_minimum?_iff [Min α] [LE α]
(le_min_iff : a b c : α, a min b c a b a c) :
{xs : List α} xs.min? = some a {x}, x a b, b xs x b
{xs : List α} xs.minimum? = some a {x}, x a b, b xs x b
| nil => by simp
| cons x xs => by
rw [min?]
rw [minimum?]
intro eq y
simp only [Option.some.injEq] at eq
induction xs generalizing x with
@@ -75,58 +67,46 @@ theorem le_min?_iff [Min α] [LE α]
-- This could be refactored by designing appropriate typeclasses to replace `le_refl`, `min_eq_or`,
-- and `le_min_iff`.
theorem min?_eq_some_iff [Min α] [LE α] [anti : Std.Antisymm ((· : α) ·)]
theorem minimum?_eq_some_iff [Min α] [LE α] [anti : Antisymm ((· : α) ·)]
(le_refl : a : α, a a)
(min_eq_or : a b : α, min a b = a min a b = b)
(le_min_iff : a b c : α, a min b c a b a c) {xs : List α} :
xs.min? = some a a xs b, b xs a b := by
refine fun h => min?_mem min_eq_or h, (le_min?_iff le_min_iff h).1 (le_refl _), ?_
xs.minimum? = some a a xs b, b xs a b := by
refine fun h => minimum?_mem min_eq_or h, (le_minimum?_iff le_min_iff h).1 (le_refl _), ?_
intro h₁, h₂
cases xs with
| nil => simp at h₁
| cons x xs =>
exact congrArg some <| anti.1
((le_min?_iff le_min_iff (xs := x::xs) rfl).1 (le_refl _) _ h₁)
(h₂ _ (min?_mem min_eq_or (xs := x::xs) rfl))
((le_minimum?_iff le_min_iff (xs := x::xs) rfl).1 (le_refl _) _ h₁)
(h₂ _ (minimum?_mem min_eq_or (xs := x::xs) rfl))
theorem min?_replicate [Min α] {n : Nat} {a : α} (w : min a a = a) :
(replicate n a).min? = if n = 0 then none else some a := by
theorem minimum?_replicate [Min α] {n : Nat} {a : α} (w : min a a = a) :
(replicate n a).minimum? = if n = 0 then none else some a := by
induction n with
| zero => rfl
| succ n ih => cases n <;> simp_all [replicate_succ, min?_cons']
| succ n ih => cases n <;> simp_all [replicate_succ, minimum?_cons]
@[simp] theorem min?_replicate_of_pos [Min α] {n : Nat} {a : α} (w : min a a = a) (h : 0 < n) :
(replicate n a).min? = some a := by
simp [min?_replicate, Nat.ne_of_gt h, w]
@[simp] theorem minimum?_replicate_of_pos [Min α] {n : Nat} {a : α} (w : min a a = a) (h : 0 < n) :
(replicate n a).minimum? = some a := by
simp [minimum?_replicate, Nat.ne_of_gt h, w]
theorem foldl_min [Min α] [Std.IdempotentOp (min : α α α)] [Std.Associative (min : α α α)]
{l : List α} {a : α} : l.foldl (init := a) min = min a (l.min?.getD a) := by
cases l <;> simp [min?, foldl_assoc, Std.IdempotentOp.idempotent]
/-! ### maximum? -/
/-! ### max? -/
@[simp] theorem maximum?_nil [Max α] : ([] : List α).maximum? = none := rfl
@[simp] theorem max?_nil [Max α] : ([] : List α).max? = none := rfl
-- We don't put `@[simp]` on `max?_cons'`,
-- We don't put `@[simp]` on `maximum?_cons`,
-- because the definition in terms of `foldl` is not useful for proofs.
theorem max?_cons' [Max α] {xs : List α} : (x :: xs).max? = foldl max x xs := rfl
theorem maximum?_cons [Max α] {xs : List α} : (x :: xs).maximum? = foldl max x xs := rfl
@[simp] theorem max?_cons [Max α] [Std.Associative (max : α α α)] {xs : List α} :
(x :: xs).max? = some (xs.max?.elim x (max x)) := by
cases xs <;> simp [max?_cons', foldl_assoc]
@[simp] theorem maximum?_eq_none_iff {xs : List α} [Max α] : xs.maximum? = none xs = [] := by
cases xs <;> simp [maximum?]
@[simp] theorem max?_eq_none_iff {xs : List α} [Max α] : xs.max? = none xs = [] := by
cases xs <;> simp [max?]
theorem isSome_max?_of_mem {l : List α} [Max α] {a : α} (h : a l) :
l.max?.isSome := by
cases l <;> simp_all [List.max?_cons']
theorem max?_mem [Max α] (min_eq_or : a b : α, max a b = a max a b = b) :
{xs : List α} xs.max? = some a a xs
theorem maximum?_mem [Max α] (min_eq_or : a b : α, max a b = a max a b = b) :
{xs : List α} xs.maximum? = some a a xs
| nil => by simp
| cons x xs => by
rw [max?]; rintro
rw [maximum?]; rintro
induction xs generalizing x with simp at *
| cons y xs ih =>
rcases ih (max x y) with h | h <;> simp [h]
@@ -134,61 +114,40 @@ theorem max?_mem [Max α] (min_eq_or : ∀ a b : α, max a b = a max a b = b
-- See also `Init.Data.List.Nat.Basic` for specialisations of the next two results to `Nat`.
theorem max?_le_iff [Max α] [LE α]
theorem maximum?_le_iff [Max α] [LE α]
(max_le_iff : a b c : α, max b c a b a c a) :
{xs : List α} xs.max? = some a {x}, a x b xs, b x
{xs : List α} xs.maximum? = some a {x}, a x b xs, b x
| nil => by simp
| cons x xs => by
rw [max?]; rintro y
rw [maximum?]; rintro y
induction xs generalizing x with
| nil => simp
| cons y xs ih => simp [ih, max_le_iff, and_assoc]
-- This could be refactored by designing appropriate typeclasses to replace `le_refl`, `max_eq_or`,
-- and `le_min_iff`.
theorem max?_eq_some_iff [Max α] [LE α] [anti : Std.Antisymm ((· : α) ·)]
theorem maximum?_eq_some_iff [Max α] [LE α] [anti : Antisymm ((· : α) ·)]
(le_refl : a : α, a a)
(max_eq_or : a b : α, max a b = a max a b = b)
(max_le_iff : a b c : α, max b c a b a c a) {xs : List α} :
xs.max? = some a a xs b xs, b a := by
refine fun h => max?_mem max_eq_or h, (max?_le_iff max_le_iff h).1 (le_refl _), ?_
xs.maximum? = some a a xs b xs, b a := by
refine fun h => maximum?_mem max_eq_or h, (maximum?_le_iff max_le_iff h).1 (le_refl _), ?_
intro h₁, h₂
cases xs with
| nil => simp at h₁
| cons x xs =>
exact congrArg some <| anti.1
(h₂ _ (max?_mem max_eq_or (xs := x::xs) rfl))
((max?_le_iff max_le_iff (xs := x::xs) rfl).1 (le_refl _) _ h₁)
(h₂ _ (maximum?_mem max_eq_or (xs := x::xs) rfl))
((maximum?_le_iff max_le_iff (xs := x::xs) rfl).1 (le_refl _) _ h₁)
theorem max?_replicate [Max α] {n : Nat} {a : α} (w : max a a = a) :
(replicate n a).max? = if n = 0 then none else some a := by
theorem maximum?_replicate [Max α] {n : Nat} {a : α} (w : max a a = a) :
(replicate n a).maximum? = if n = 0 then none else some a := by
induction n with
| zero => rfl
| succ n ih => cases n <;> simp_all [replicate_succ, max?_cons']
| succ n ih => cases n <;> simp_all [replicate_succ, maximum?_cons]
@[simp] theorem max?_replicate_of_pos [Max α] {n : Nat} {a : α} (w : max a a = a) (h : 0 < n) :
(replicate n a).max? = some a := by
simp [max?_replicate, Nat.ne_of_gt h, w]
theorem foldl_max [Max α] [Std.IdempotentOp (max : α α α)] [Std.Associative (max : α α α)]
{l : List α} {a : α} : l.foldl (init := a) max = max a (l.max?.getD a) := by
cases l <;> simp [max?, foldl_assoc, Std.IdempotentOp.idempotent]
@[deprecated min?_nil (since := "2024-09-29")] abbrev minimum?_nil := @min?_nil
@[deprecated min?_cons (since := "2024-09-29")] abbrev minimum?_cons := @min?_cons
@[deprecated min?_eq_none_iff (since := "2024-09-29")] abbrev mininmum?_eq_none_iff := @min?_eq_none_iff
@[deprecated min?_mem (since := "2024-09-29")] abbrev minimum?_mem := @min?_mem
@[deprecated le_min?_iff (since := "2024-09-29")] abbrev le_minimum?_iff := @le_min?_iff
@[deprecated min?_eq_some_iff (since := "2024-09-29")] abbrev minimum?_eq_some_iff := @min?_eq_some_iff
@[deprecated min?_replicate (since := "2024-09-29")] abbrev minimum?_replicate := @min?_replicate
@[deprecated min?_replicate_of_pos (since := "2024-09-29")] abbrev minimum?_replicate_of_pos := @min?_replicate_of_pos
@[deprecated max?_nil (since := "2024-09-29")] abbrev maximum?_nil := @max?_nil
@[deprecated max?_cons (since := "2024-09-29")] abbrev maximum?_cons := @max?_cons
@[deprecated max?_eq_none_iff (since := "2024-09-29")] abbrev maximum?_eq_none_iff := @max?_eq_none_iff
@[deprecated max?_mem (since := "2024-09-29")] abbrev maximum?_mem := @max?_mem
@[deprecated max?_le_iff (since := "2024-09-29")] abbrev maximum?_le_iff := @max?_le_iff
@[deprecated max?_eq_some_iff (since := "2024-09-29")] abbrev maximum?_eq_some_iff := @max?_eq_some_iff
@[deprecated max?_replicate (since := "2024-09-29")] abbrev maximum?_replicate := @max?_replicate
@[deprecated max?_replicate_of_pos (since := "2024-09-29")] abbrev maximum?_replicate_of_pos := @max?_replicate_of_pos
@[simp] theorem maximum?_replicate_of_pos [Max α] {n : Nat} {a : α} (w : max a a = a) (h : 0 < n) :
(replicate n a).maximum? = some a := by
simp [maximum?_replicate, Nat.ne_of_gt h, w]
end List

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@@ -5,7 +5,6 @@ Authors: Parikshit Khanna, Jeremy Avigad, Leonardo de Moura, Floris van Doorn, M
-/
prelude
import Init.Data.List.TakeDrop
import Init.Data.List.Attach
/-!
# Lemmas about `List.mapM` and `List.forM`.
@@ -49,43 +48,9 @@ theorem mapM'_eq_mapM [Monad m] [LawfulMonad m] (f : α → m β) (l : List α)
@[simp] theorem mapM_cons [Monad m] [LawfulMonad m] (f : α m β) :
(a :: l).mapM f = (return ( f a) :: ( l.mapM f)) := by simp [ mapM'_eq_mapM, mapM']
@[simp] theorem mapM_id {l : List α} {f : α Id β} : l.mapM f = l.map f := by
induction l <;> simp_all
@[simp] theorem mapM_append [Monad m] [LawfulMonad m] (f : α m β) {l₁ l₂ : List α} :
(l₁ ++ l₂).mapM f = (return ( l₁.mapM f) ++ ( l₂.mapM f)) := by induction l₁ <;> simp [*]
/-- Auxiliary lemma for `mapM_eq_reverse_foldlM_cons`. -/
theorem foldlM_cons_eq_append [Monad m] [LawfulMonad m] (f : α m β) (as : List α) (b : β) (bs : List β) :
(as.foldlM (init := b :: bs) fun acc a => return (( f a) :: acc)) =
(· ++ b :: bs) <$> as.foldlM (init := []) fun acc a => return (( f a) :: acc) := by
induction as generalizing b bs with
| nil => simp
| cons a as ih =>
simp only [bind_pure_comp] at ih
simp [ih, _root_.map_bind, Functor.map_map, Function.comp_def]
theorem mapM_eq_reverse_foldlM_cons [Monad m] [LawfulMonad m] (f : α m β) (l : List α) :
mapM f l = reverse <$> (l.foldlM (fun acc a => return (( f a) :: acc)) []) := by
rw [ mapM'_eq_mapM]
induction l with
| nil => simp
| cons a as ih =>
simp only [mapM'_cons, ih, bind_map_left, foldlM_cons, LawfulMonad.bind_assoc, pure_bind,
foldlM_cons_eq_append, _root_.map_bind, Functor.map_map, Function.comp_def, reverse_append,
reverse_cons, reverse_nil, nil_append, singleton_append]
simp [bind_pure_comp]
/-! ### foldlM and foldrM -/
theorem foldlM_map [Monad m] (f : β₁ β₂) (g : α β₂ m α) (l : List β₁) (init : α) :
(l.map f).foldlM g init = l.foldlM (fun x y => g x (f y)) init := by
induction l generalizing g init <;> simp [*]
theorem foldrM_map [Monad m] [LawfulMonad m] (f : β₁ β₂) (g : β₂ α m α) (l : List β₁)
(init : α) : (l.map f).foldrM g init = l.foldrM (fun x y => g (f x) y) init := by
induction l generalizing g init <;> simp [*]
/-! ### forM -/
-- We use `List.forM` as the simp normal form, rather that `ForM.forM`.
@@ -101,139 +66,4 @@ theorem foldrM_map [Monad m] [LawfulMonad m] (f : β₁ → β₂) (g : β₂
(l₁ ++ l₂).forM f = (do l₁.forM f; l₂.forM f) := by
induction l₁ <;> simp [*]
/-! ### forIn' -/
theorem forIn'_loop_congr [Monad m] {as bs : List α}
{f : (a' : α) a' as β m (ForInStep β)}
{g : (a' : α) a' bs β m (ForInStep β)}
{b : β} (ha : ys, ys ++ xs = as) (hb : ys, ys ++ xs = bs)
(h : a m m' b, f a m b = g a m' b) : forIn'.loop as f xs b ha = forIn'.loop bs g xs b hb := by
induction xs generalizing b with
| nil => simp [forIn'.loop]
| cons a xs ih =>
simp only [forIn'.loop] at *
congr 1
· rw [h]
· funext s
obtain b | b := s
· rfl
· simp
rw [ih]
@[simp] theorem forIn'_cons [Monad m] {a : α} {as : List α}
(f : (a' : α) a' a :: as β m (ForInStep β)) (b : β) :
forIn' (a::as) b f = f a (mem_cons_self a as) b >>=
fun | ForInStep.done b => pure b | ForInStep.yield b => forIn' as b fun a' m b => f a' (mem_cons_of_mem a m) b := by
simp only [forIn', List.forIn', forIn'.loop]
congr 1
funext s
obtain b | b := s
· rfl
· apply forIn'_loop_congr
intros
rfl
@[simp] theorem forIn_cons [Monad m] (f : α β m (ForInStep β)) (a : α) (as : List α) (b : β) :
forIn (a::as) b f = f a b >>= fun | ForInStep.done b => pure b | ForInStep.yield b => forIn as b f := by
have := forIn'_cons (a := a) (as := as) (fun a' _ b => f a' b) b
simpa only [forIn'_eq_forIn]
@[congr] theorem forIn'_congr [Monad m] {as bs : List α} (w : as = bs)
{b b' : β} (hb : b = b')
{f : (a' : α) a' as β m (ForInStep β)}
{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
induction bs generalizing as b b' with
| nil =>
subst w
simp [hb, forIn'_nil]
| cons b bs ih =>
cases as with
| nil => simp at w
| cons a as =>
simp only [cons.injEq] at w
obtain rfl, rfl := w
simp only [forIn'_cons]
congr 1
· simp [h, hb]
· funext s
obtain b | b := s
· rfl
· simp
rw [ih rfl rfl]
intro a m b
exact h a (mem_cons_of_mem _ m) b
/--
We can express a for loop over a list as a fold,
in which whenever we reach `.done b` we keep that value through the rest of the fold.
-/
theorem forIn'_eq_foldlM [Monad m] [LawfulMonad m]
(l : List α) (f : (a : α) a l β m (ForInStep β)) (init : β) :
forIn' l init f = ForInStep.value <$>
l.attach.foldlM (fun b a => match b with
| .yield b => f a.1 a.2 b
| .done b => pure (.done b)) (ForInStep.yield init) := by
induction l generalizing init with
| nil => simp
| cons a as ih =>
simp only [forIn'_cons, attach_cons, foldlM_cons, _root_.map_bind]
congr 1
funext x
match x with
| .done b =>
clear ih
dsimp
induction as with
| nil => simp
| cons a as ih =>
simp only [attach_cons, map_cons, map_map, Function.comp_def, foldlM_cons, pure_bind]
specialize ih (fun a m b => f a (by
simp only [mem_cons] at m
rcases m with rfl|m
· apply mem_cons_self
· exact mem_cons_of_mem _ (mem_cons_of_mem _ m)) b)
simp [ih, List.foldlM_map]
| .yield b =>
simp [ih, List.foldlM_map]
/--
We can express a for loop over a list as a fold,
in which whenever we reach `.done b` we keep that value through the rest of the fold.
-/
theorem forIn_eq_foldlM [Monad m] [LawfulMonad m]
(f : α β m (ForInStep β)) (init : β) (l : List α) :
forIn l init f = ForInStep.value <$>
l.foldlM (fun b a => match b with
| .yield b => f a b
| .done b => pure (.done b)) (ForInStep.yield init) := by
induction l generalizing init with
| nil => simp
| cons a as ih =>
simp only [foldlM_cons, bind_pure_comp, forIn_cons, _root_.map_bind]
congr 1
funext x
match x with
| .done b =>
clear ih
dsimp
induction as with
| nil => simp
| cons a as ih => simp [ih]
| .yield b =>
simp [ih]
/-! ### allM -/
theorem allM_eq_not_anyM_not [Monad m] [LawfulMonad m] (p : α m Bool) (as : List α) :
allM p as = (! ·) <$> anyM ((! ·) <$> p ·) as := by
induction as with
| nil => simp
| cons a as ih =>
simp only [allM, anyM, bind_map_left, _root_.map_bind]
congr
funext b
split <;> simp_all
end List

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@@ -12,5 +12,3 @@ import Init.Data.List.Nat.TakeDrop
import Init.Data.List.Nat.Count
import Init.Data.List.Nat.Erase
import Init.Data.List.Nat.Find
import Init.Data.List.Nat.BEq
import Init.Data.List.Nat.Modify

View File

@@ -1,47 +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.Nat.Lemmas
import Init.Data.List.Basic
namespace List
/-! ### isEqv-/
theorem isEqv_eq_decide (a b : List α) (r) :
isEqv a b r = if h : a.length = b.length then
decide ( (i : Nat) (h' : i < a.length), r (a[i]'(h h')) (b[i]'(h h'))) else false := by
induction a generalizing b with
| nil =>
cases b <;> simp
| cons a as ih =>
cases b with
| nil => simp
| cons b bs =>
simp only [isEqv, ih, length_cons, Nat.add_right_cancel_iff]
split <;> simp [Nat.forall_lt_succ_left']
/-! ### beq -/
theorem beq_eq_isEqv [BEq α] (a b : List α) : a.beq b = isEqv a b (· == ·) := by
induction a generalizing b with
| nil =>
cases b <;> simp
| cons a as ih =>
cases b with
| nil => simp
| cons b bs =>
simp only [beq_cons₂, ih, isEqv_eq_decide, length_cons, Nat.add_right_cancel_iff,
Nat.forall_lt_succ_left', getElem_cons_zero, getElem_cons_succ, Bool.decide_and,
Bool.decide_eq_true]
split <;> simp
theorem beq_eq_decide [BEq α] (a b : List α) :
(a == b) = if h : a.length = b.length then
decide ( (i : Nat) (h' : i < a.length), a[i] == b[i]'(h h')) else false := by
simp [BEq.beq, beq_eq_isEqv, isEqv_eq_decide]
end List

View File

@@ -86,66 +86,164 @@ theorem mem_eraseIdx_iff_getElem? {x : α} {l} {k} : x ∈ eraseIdx l k ↔ ∃
obtain h', - := getElem?_eq_some_iff.1 h
exact h', h
/-! ### min? -/
/-! ### minimum? -/
-- A specialization of `min?_eq_some_iff` to Nat.
theorem min?_eq_some_iff' {xs : List Nat} :
xs.min? = some a (a xs b xs, a b) :=
min?_eq_some_iff
-- A specialization of `minimum?_eq_some_iff` to Nat.
theorem minimum?_eq_some_iff' {xs : List Nat} :
xs.minimum? = some a (a xs b xs, a b) :=
minimum?_eq_some_iff
(le_refl := Nat.le_refl)
(min_eq_or := fun _ _ => Nat.min_def .. by split <;> simp)
(le_min_iff := fun _ _ _ => Nat.le_min)
(min_eq_or := fun _ _ => by omega)
(le_min_iff := fun _ _ _ => by omega)
theorem min?_get_le_of_mem {l : List Nat} {a : Nat} (h : a l) :
l.min?.get (isSome_min?_of_mem h) a := by
induction l with
-- This could be generalized,
-- but will first require further work on order typeclasses in the core repository.
theorem minimum?_cons' {a : Nat} {l : List Nat} :
(a :: l).minimum? = some (match l.minimum? with
| none => a
| some m => min a m) := by
rw [minimum?_eq_some_iff']
split <;> rename_i h m
· simp_all
· rw [minimum?_eq_some_iff'] at m
obtain m, le := m
rw [Nat.min_def]
constructor
· split
· exact mem_cons_self a l
· exact mem_cons_of_mem a m
· intro b m
cases List.mem_cons.1 m with
| inl => split <;> omega
| inr h =>
specialize le b h
split <;> omega
theorem foldl_min
{α : Type _} [Min α] [Std.IdempotentOp (min : α α α)] [Std.Associative (min : α α α)]
{l : List α} {a : α} :
l.foldl (init := a) min = min a (l.minimum?.getD a) := by
cases l with
| nil => simp [Std.IdempotentOp.idempotent]
| cons b l =>
simp only [minimum?]
induction l generalizing a b with
| nil => simp
| cons c l ih => simp [ih, Std.Associative.assoc]
theorem foldl_min_right {α β : Type _}
[Min β] [Std.IdempotentOp (min : β β β)] [Std.Associative (min : β β β)]
{l : List α} {b : β} {f : α β} :
(l.foldl (init := b) fun acc a => min acc (f a)) = min b ((l.map f).minimum?.getD b) := by
rw [ foldl_map, foldl_min]
theorem foldl_min_le {l : List Nat} {a : Nat} : l.foldl (init := a) min a := by
induction l generalizing a with
| nil => simp
| cons c l ih =>
simp only [foldl_cons]
exact Nat.le_trans ih (Nat.min_le_left _ _)
theorem foldl_min_min_of_le {l : List Nat} {a b : Nat} (h : a b) :
l.foldl (init := a) min b :=
Nat.le_trans (foldl_min_le) h
theorem minimum?_getD_le_of_mem {l : List Nat} {a k : Nat} (h : a l) :
l.minimum?.getD k a := by
cases l with
| nil => simp at h
| cons b t ih =>
simp only [min?_cons, Option.get_some] at ih
rcases mem_cons.1 h with (rfl|h)
· cases t.min? with
| none => simp
| some b => simpa using Nat.min_le_left _ _
· obtain q, hq := Option.isSome_iff_exists.1 (isSome_min?_of_mem h)
simp only [hq, Option.elim_some] at ih
exact Nat.le_trans (Nat.min_le_right _ _) (ih h)
| cons b l =>
simp [minimum?_cons]
simp at h
rcases h with (rfl | h)
· exact foldl_min_le
· induction l generalizing b with
| nil => simp_all
| cons c l ih =>
simp only [foldl_cons]
simp at h
rcases h with (rfl | h)
· exact foldl_min_min_of_le (Nat.min_le_right _ _)
· exact ih _ h
theorem min?_getD_le_of_mem {l : List Nat} {a k : Nat} (h : a l) : l.min?.getD k a :=
Option.get_eq_getD _ min?_get_le_of_mem h
/-! ### maximum? -/
/-! ### max? -/
-- A specialization of `max?_eq_some_iff` to Nat.
theorem max?_eq_some_iff' {xs : List Nat} :
xs.max? = some a (a xs b xs, b a) :=
max?_eq_some_iff
-- A specialization of `maximum?_eq_some_iff` to Nat.
theorem maximum?_eq_some_iff' {xs : List Nat} :
xs.maximum? = some a (a xs b xs, b a) :=
maximum?_eq_some_iff
(le_refl := Nat.le_refl)
(max_eq_or := fun _ _ => Nat.max_def .. by split <;> simp)
(max_le_iff := fun _ _ _ => Nat.max_le)
(max_eq_or := fun _ _ => by omega)
(max_le_iff := fun _ _ _ => by omega)
theorem le_max?_get_of_mem {l : List Nat} {a : Nat} (h : a l) :
a l.max?.get (isSome_max?_of_mem h) := by
induction l with
-- This could be generalized,
-- but will first require further work on order typeclasses in the core repository.
theorem maximum?_cons' {a : Nat} {l : List Nat} :
(a :: l).maximum? = some (match l.maximum? with
| none => a
| some m => max a m) := by
rw [maximum?_eq_some_iff']
split <;> rename_i h m
· simp_all
· rw [maximum?_eq_some_iff'] at m
obtain m, le := m
rw [Nat.max_def]
constructor
· split
· exact mem_cons_of_mem a m
· exact mem_cons_self a l
· intro b m
cases List.mem_cons.1 m with
| inl => split <;> omega
| inr h =>
specialize le b h
split <;> omega
theorem foldl_max
{α : Type _} [Max α] [Std.IdempotentOp (max : α α α)] [Std.Associative (max : α α α)]
{l : List α} {a : α} :
l.foldl (init := a) max = max a (l.maximum?.getD a) := by
cases l with
| nil => simp [Std.IdempotentOp.idempotent]
| cons b l =>
simp only [maximum?]
induction l generalizing a b with
| nil => simp
| cons c l ih => simp [ih, Std.Associative.assoc]
theorem foldl_max_right {α β : Type _}
[Max β] [Std.IdempotentOp (max : β β β)] [Std.Associative (max : β β β)]
{l : List α} {b : β} {f : α β} :
(l.foldl (init := b) fun acc a => max acc (f a)) = max b ((l.map f).maximum?.getD b) := by
rw [ foldl_map, foldl_max]
theorem le_foldl_max {l : List Nat} {a : Nat} : a l.foldl (init := a) max := by
induction l generalizing a with
| nil => simp
| cons c l ih =>
simp only [foldl_cons]
exact Nat.le_trans (Nat.le_max_left _ _) ih
theorem le_foldl_max_of_le {l : List Nat} {a b : Nat} (h : a b) :
a l.foldl (init := b) max :=
Nat.le_trans h (le_foldl_max)
theorem le_maximum?_getD_of_mem {l : List Nat} {a k : Nat} (h : a l) :
a l.maximum?.getD k := by
cases l with
| nil => simp at h
| cons b t ih =>
simp only [max?_cons, Option.get_some] at ih
rcases mem_cons.1 h with (rfl|h)
· cases t.max? with
| none => simp
| some b => simpa using Nat.le_max_left _ _
· obtain q, hq := Option.isSome_iff_exists.1 (isSome_max?_of_mem h)
simp only [hq, Option.elim_some] at ih
exact Nat.le_trans (ih h) (Nat.le_max_right _ _)
theorem le_max?_getD_of_mem {l : List Nat} {a k : Nat} (h : a l) :
a l.max?.getD k :=
Option.get_eq_getD _ le_max?_get_of_mem h
@[deprecated min?_eq_some_iff' (since := "2024-09-29")] abbrev minimum?_eq_some_iff' := @min?_eq_some_iff'
@[deprecated min?_cons' (since := "2024-09-29")] abbrev minimum?_cons' := @min?_cons'
@[deprecated min?_getD_le_of_mem (since := "2024-09-29")] abbrev minimum?_getD_le_of_mem := @min?_getD_le_of_mem
@[deprecated max?_eq_some_iff' (since := "2024-09-29")] abbrev maximum?_eq_some_iff' := @max?_eq_some_iff'
@[deprecated max?_cons' (since := "2024-09-29")] abbrev maximum?_cons' := @max?_cons'
@[deprecated le_max?_getD_of_mem (since := "2024-09-29")] abbrev le_maximum?_getD_of_mem := @le_max?_getD_of_mem
| cons b l =>
simp [maximum?_cons]
simp at h
rcases h with (rfl | h)
· exact le_foldl_max
· induction l generalizing b with
| nil => simp_all
| cons c l ih =>
simp only [foldl_cons]
simp at h
rcases h with (rfl | h)
· exact le_foldl_max_of_le (Nat.le_max_right b a)
· exact ih _ h
end List

View File

@@ -10,7 +10,7 @@ import Init.Data.List.Erase
namespace List
theorem getElem?_eraseIdx (l : List α) (i : Nat) (j : Nat) :
(l.eraseIdx i)[j]? = if j < i then l[j]? else l[j + 1]? := by
(l.eraseIdx i)[j]? = if h : j < i then l[j]? else l[j + 1]? := by
rw [eraseIdx_eq_take_drop_succ, getElem?_append]
split <;> rename_i h
· rw [getElem?_take]

View File

@@ -1,295 +0,0 @@
/-
Copyright (c) 2014 Parikshit Khanna. All rights reserved.
Released under Apache 2.0 license as described in the file LICENSE.
Authors: Parikshit Khanna, Jeremy Avigad, Leonardo de Moura, Floris van Doorn, Mario Carneiro
-/
prelude
import Init.Data.List.Nat.TakeDrop
import Init.Data.List.Nat.Erase
namespace List
/-! ### modifyHead -/
@[simp] theorem length_modifyHead {f : α α} {l : List α} : (l.modifyHead f).length = l.length := by
cases l <;> simp [modifyHead]
theorem modifyHead_eq_set [Inhabited α] (f : α α) (l : List α) :
l.modifyHead f = l.set 0 (f (l[0]?.getD default)) := by cases l <;> simp [modifyHead]
@[simp] theorem modifyHead_eq_nil_iff {f : α α} {l : List α} :
l.modifyHead f = [] l = [] := by cases l <;> simp [modifyHead]
@[simp] theorem modifyHead_modifyHead {l : List α} {f g : α α} :
(l.modifyHead f).modifyHead g = l.modifyHead (g f) := by cases l <;> simp [modifyHead]
theorem getElem_modifyHead {l : List α} {f : α α} {n} (h : n < (l.modifyHead f).length) :
(l.modifyHead f)[n] = if h' : n = 0 then f (l[0]'(by simp at h; omega)) else l[n]'(by simpa using h) := by
cases l with
| nil => simp at h
| cons hd tl => cases n <;> simp
@[simp] theorem getElem_modifyHead_zero {l : List α} {f : α α} {h} :
(l.modifyHead f)[0] = f (l[0]'(by simpa using h)) := by simp [getElem_modifyHead]
@[simp] theorem getElem_modifyHead_succ {l : List α} {f : α α} {n} (h : n + 1 < (l.modifyHead f).length) :
(l.modifyHead f)[n + 1] = l[n + 1]'(by simpa using h) := by simp [getElem_modifyHead]
theorem getElem?_modifyHead {l : List α} {f : α α} {n} :
(l.modifyHead f)[n]? = if n = 0 then l[n]?.map f else l[n]? := by
cases l with
| nil => simp
| cons hd tl => cases n <;> simp
@[simp] theorem getElem?_modifyHead_zero {l : List α} {f : α α} :
(l.modifyHead f)[0]? = l[0]?.map f := by simp [getElem?_modifyHead]
@[simp] theorem getElem?_modifyHead_succ {l : List α} {f : α α} {n} :
(l.modifyHead f)[n + 1]? = l[n + 1]? := by simp [getElem?_modifyHead]
@[simp] theorem head_modifyHead (f : α α) (l : List α) (h) :
(l.modifyHead f).head h = f (l.head (by simpa using h)) := by
cases l with
| nil => simp at h
| cons hd tl => simp
@[simp] theorem head?_modifyHead {l : List α} {f : α α} :
(l.modifyHead f).head? = l.head?.map f := by cases l <;> simp
@[simp] theorem tail_modifyHead {f : α α} {l : List α} :
(l.modifyHead f).tail = l.tail := by cases l <;> simp
@[simp] theorem take_modifyHead {f : α α} {l : List α} {n} :
(l.modifyHead f).take n = (l.take n).modifyHead f := by
cases l <;> cases n <;> simp
@[simp] theorem drop_modifyHead_of_pos {f : α α} {l : List α} {n} (h : 0 < n) :
(l.modifyHead f).drop n = l.drop n := by
cases l <;> cases n <;> simp_all
@[simp] theorem eraseIdx_modifyHead_zero {f : α α} {l : List α} :
(l.modifyHead f).eraseIdx 0 = l.eraseIdx 0 := by cases l <;> simp
@[simp] theorem eraseIdx_modifyHead_of_pos {f : α α} {l : List α} {n} (h : 0 < n) :
(l.modifyHead f).eraseIdx n = (l.eraseIdx n).modifyHead f := by cases l <;> cases n <;> simp_all
@[simp] theorem modifyHead_id : modifyHead (id : α α) = id := by funext l; cases l <;> simp
/-! ### modifyTailIdx -/
@[simp] theorem modifyTailIdx_id : n (l : List α), l.modifyTailIdx id n = l
| 0, _ => rfl
| _+1, [] => rfl
| n+1, a :: l => congrArg (cons a) (modifyTailIdx_id n l)
theorem eraseIdx_eq_modifyTailIdx : n (l : List α), eraseIdx l n = modifyTailIdx tail n l
| 0, l => by cases l <;> rfl
| _+1, [] => rfl
| _+1, _ :: _ => congrArg (cons _) (eraseIdx_eq_modifyTailIdx _ _)
@[simp] theorem length_modifyTailIdx (f : List α List α) (H : l, length (f l) = length l) :
n l, length (modifyTailIdx f n l) = length l
| 0, _ => H _
| _+1, [] => rfl
| _+1, _ :: _ => congrArg (·+1) (length_modifyTailIdx _ H _ _)
theorem modifyTailIdx_add (f : List α List α) (n) (l₁ l₂ : List α) :
modifyTailIdx f (l₁.length + n) (l₁ ++ l₂) = l₁ ++ modifyTailIdx f n l₂ := by
induction l₁ <;> simp [*, Nat.succ_add]
theorem modifyTailIdx_eq_take_drop (f : List α List α) (H : f [] = []) :
n l, modifyTailIdx f n l = take n l ++ f (drop n l)
| 0, _ => rfl
| _ + 1, [] => H.symm
| n + 1, b :: l => congrArg (cons b) (modifyTailIdx_eq_take_drop f H n l)
theorem exists_of_modifyTailIdx (f : List α List α) {n} {l : List α} (h : n l.length) :
l₁ l₂, l = l₁ ++ l₂ l₁.length = n modifyTailIdx f n l = l₁ ++ f l₂ :=
have _, _, eq, hl : l₁ l₂, l = l₁ ++ l₂ l₁.length = n :=
_, _, (take_append_drop n l).symm, length_take_of_le h
_, _, eq, hl, hl eq modifyTailIdx_add (n := 0) ..
/-! ### modify -/
@[simp] theorem modify_nil (f : α α) (n) : [].modify f n = [] := by cases n <;> rfl
@[simp] theorem modify_zero_cons (f : α α) (a : α) (l : List α) :
(a :: l).modify f 0 = f a :: l := rfl
@[simp] theorem modify_succ_cons (f : α α) (a : α) (l : List α) (n) :
(a :: l).modify f (n + 1) = a :: l.modify f n := by rfl
theorem modifyHead_eq_modify_zero (f : α α) (l : List α) :
l.modifyHead f = l.modify f 0 := by cases l <;> simp
@[simp] theorem modify_eq_nil_iff (f : α α) (n) (l : List α) :
l.modify f n = [] l = [] := by cases l <;> cases n <;> simp
theorem getElem?_modify (f : α α) :
n (l : List α) m, (modify f n l)[m]? = (fun a => if n = m then f a else a) <$> l[m]?
| n, l, 0 => by cases l <;> cases n <;> simp
| n, [], _+1 => by cases n <;> rfl
| 0, _ :: l, m+1 => by cases h : l[m]? <;> simp [h, modify, m.succ_ne_zero.symm]
| n+1, a :: l, m+1 => by
simp only [modify_succ_cons, getElem?_cons_succ, Nat.reduceEqDiff, Option.map_eq_map]
refine (getElem?_modify f n l m).trans ?_
cases h' : l[m]? <;> by_cases h : n = m <;>
simp [h, if_pos, if_neg, Option.map, mt Nat.succ.inj, not_false_iff, h']
@[simp] theorem length_modify (f : α α) : n l, length (modify f n l) = length l :=
length_modifyTailIdx _ fun l => by cases l <;> rfl
@[simp] theorem getElem?_modify_eq (f : α α) (n) (l : List α) :
(modify f n l)[n]? = f <$> l[n]? := by
simp only [getElem?_modify, if_pos]
@[simp] theorem getElem?_modify_ne (f : α α) {m n} (l : List α) (h : m n) :
(modify f m l)[n]? = l[n]? := by
simp only [getElem?_modify, if_neg h, id_map']
theorem getElem_modify (f : α α) (n) (l : List α) (m) (h : m < (modify f n l).length) :
(modify f n l)[m] =
if n = m then f (l[m]'(by simp at h; omega)) else l[m]'(by simp at h; omega) := by
rw [getElem_eq_iff, getElem?_modify]
simp at h
simp [h]
@[simp] theorem getElem_modify_eq (f : α α) (n) (l : List α) (h) :
(modify f n l)[n] = f (l[n]'(by simpa using h)) := by simp [getElem_modify]
@[simp] theorem getElem_modify_ne (f : α α) {m n} (l : List α) (h : m n) (h') :
(modify f m l)[n] = l[n]'(by simpa using h') := by simp [getElem_modify, h]
theorem modify_eq_self {f : α α} {n} {l : List α} (h : l.length n) :
l.modify f n = l := by
apply ext_getElem
· simp
· intro m h₁ h₂
simp only [getElem_modify, ite_eq_right_iff]
intro h
omega
theorem modify_modify_eq (f g : α α) (n) (l : List α) :
(modify f n l).modify g n = modify (g f) n l := by
apply ext_getElem
· simp
· intro m h₁ h₂
simp only [getElem_modify, Function.comp_apply]
split <;> simp
theorem modify_modify_ne (f g : α α) {m n} (l : List α) (h : m n) :
(modify f m l).modify g n = (l.modify g n).modify f m := by
apply ext_getElem
· simp
· intro m' h₁ h₂
simp only [getElem_modify, getElem_modify_ne, h₂]
split <;> split <;> first | rfl | omega
theorem modify_eq_set [Inhabited α] (f : α α) (n) (l : List α) :
modify f n l = l.set n (f (l[n]?.getD default)) := by
apply ext_getElem
· simp
· intro m h₁ h₂
simp [getElem_modify, getElem_set, h₂]
split <;> rename_i h
· subst h
simp only [length_modify] at h₁
simp [h₁]
· rfl
theorem modify_eq_take_drop (f : α α) :
n l, modify f n l = take n l ++ modifyHead f (drop n l) :=
modifyTailIdx_eq_take_drop _ rfl
theorem modify_eq_take_cons_drop {f : α α} {n} {l : List α} (h : n < l.length) :
modify f n l = take n l ++ f l[n] :: drop (n + 1) l := by
rw [modify_eq_take_drop, drop_eq_getElem_cons h]; rfl
theorem exists_of_modify (f : α α) {n} {l : List α} (h : n < l.length) :
l₁ a l₂, l = l₁ ++ a :: l₂ l₁.length = n modify f n l = l₁ ++ f a :: l₂ :=
match exists_of_modifyTailIdx _ (Nat.le_of_lt h) with
| _, _::_, eq, hl, H => _, _, _, eq, hl, H
| _, [], eq, hl, _ => nomatch Nat.ne_of_gt h (eq append_nil _ hl)
@[simp] theorem modify_id (n) (l : List α) : l.modify id n = l := by
simp [modify]
theorem take_modify (f : α α) (n m) (l : List α) :
(modify f m l).take n = (take n l).modify f m := by
induction n generalizing l m with
| zero => simp
| succ n ih =>
cases l with
| nil => simp
| cons hd tl =>
cases m with
| zero => simp
| succ m => simp [ih]
theorem drop_modify_of_lt (f : α α) (n m) (l : List α) (h : n < m) :
(modify f n l).drop m = l.drop m := by
apply ext_getElem
· simp
· intro m' h₁ h₂
simp only [getElem_drop, getElem_modify, ite_eq_right_iff]
intro h'
omega
theorem drop_modify_of_ge (f : α α) (n m) (l : List α) (h : n m) :
(modify f n l).drop m = modify f (n - m) (drop m l) := by
apply ext_getElem
· simp
· intro m' h₁ h₂
simp [getElem_drop, getElem_modify, ite_eq_right_iff]
split <;> split <;> first | rfl | omega
theorem eraseIdx_modify_of_eq (f : α α) (n) (l : List α) :
(modify f n l).eraseIdx n = l.eraseIdx n := by
apply ext_getElem
· simp [length_eraseIdx]
· intro m h₁ h₂
simp only [getElem_eraseIdx, getElem_modify]
split <;> split <;> first | rfl | omega
theorem eraseIdx_modify_of_lt (f : α α) (i j) (l : List α) (h : j < i) :
(modify f i l).eraseIdx j = (l.eraseIdx j).modify f (i - 1) := by
apply ext_getElem
· simp [length_eraseIdx]
· intro k h₁ h₂
simp only [getElem_eraseIdx, getElem_modify]
by_cases h' : i - 1 = k
repeat' split
all_goals (first | rfl | omega)
theorem eraseIdx_modify_of_gt (f : α α) (i j) (l : List α) (h : j > i) :
(modify f i l).eraseIdx j = (l.eraseIdx j).modify f i := by
apply ext_getElem
· simp [length_eraseIdx]
· intro k h₁ h₂
simp only [getElem_eraseIdx, getElem_modify]
by_cases h' : i = k
repeat' split
all_goals (first | rfl | omega)
theorem modify_eraseIdx_of_lt (f : α α) (i j) (l : List α) (h : j < i) :
(l.eraseIdx i).modify f j = (l.modify f j).eraseIdx i := by
apply ext_getElem
· simp [length_eraseIdx]
· intro k h₁ h₂
simp only [getElem_eraseIdx, getElem_modify]
by_cases h' : j = k + 1
repeat' split
all_goals (first | rfl | omega)
theorem modify_eraseIdx_of_ge (f : α α) (i j) (l : List α) (h : j i) :
(l.eraseIdx i).modify f j = (l.modify f (j + 1)).eraseIdx i := by
apply ext_getElem
· simp [length_eraseIdx]
· intro k h₁ h₂
simp only [getElem_eraseIdx, getElem_modify]
by_cases h' : j + 1 = k + 1
repeat' split
all_goals (first | rfl | omega)
end List

View File

@@ -154,7 +154,7 @@ theorem erase_range' :
/-! ### range -/
theorem reverse_range' : s n : Nat, reverse (range' s n) = map (s + n - 1 - ·) (range n)
| _, 0 => rfl
| s, 0 => rfl
| s, n + 1 => by
rw [range'_1_concat, reverse_append, range_succ_eq_map,
show s + (n + 1) - 1 = s + n from rfl, map, map_map]
@@ -169,7 +169,7 @@ theorem not_mem_range_self {n : Nat} : n ∉ range n := by simp
theorem self_mem_range_succ (n : Nat) : n range (n + 1) := by simp
theorem pairwise_lt_range (n : Nat) : Pairwise (· < ·) (range n) := by
simp +decide only [range_eq_range', pairwise_lt_range']
simp (config := {decide := true}) only [range_eq_range', pairwise_lt_range']
theorem pairwise_le_range (n : Nat) : Pairwise (· ·) (range n) :=
Pairwise.imp Nat.le_of_lt (pairwise_lt_range _)
@@ -177,10 +177,10 @@ theorem pairwise_le_range (n : Nat) : Pairwise (· ≤ ·) (range n) :=
theorem take_range (m n : Nat) : take m (range n) = range (min m n) := by
apply List.ext_getElem
· simp
· simp +contextual [getElem_take, Nat.lt_min]
· simp (config := { contextual := true }) [getElem_take, Nat.lt_min]
theorem nodup_range (n : Nat) : Nodup (range n) := by
simp +decide only [range_eq_range', nodup_range']
simp (config := {decide := true}) only [range_eq_range', nodup_range']
@[simp] theorem find?_range_eq_some {n : Nat} {i : Nat} {p : Nat Bool} :
(range n).find? p = some i p i i range n j, j < i !p j := by
@@ -430,10 +430,7 @@ theorem enumFrom_eq_append_iff {l : List α} {n : Nat} :
/-! ### enum -/
@[simp]
theorem enum_eq_nil_iff {l : List α} : List.enum l = [] l = [] := enumFrom_eq_nil
@[deprecated enum_eq_nil_iff (since := "2024-11-04")]
theorem enum_eq_nil {l : List α} : List.enum l = [] l = [] := enum_eq_nil_iff
theorem enum_eq_nil {l : List α} : List.enum l = [] l = [] := enumFrom_eq_nil
@[simp] theorem enum_singleton (x : α) : enum [x] = [(0, x)] := rfl
@@ -503,13 +500,4 @@ theorem enum_eq_zip_range (l : List α) : l.enum = (range l.length).zip l :=
theorem unzip_enum_eq_prod (l : List α) : l.enum.unzip = (range l.length, l) := by
simp only [enum_eq_zip_range, unzip_zip, length_range]
theorem enum_eq_cons_iff {l : List α} :
l.enum = x :: l' a as, l = a :: as x = (0, a) l' = enumFrom 1 as := by
rw [enum, enumFrom_eq_cons_iff]
theorem enum_eq_append_iff {l : List α} :
l.enum = l₁ ++ l₂
l₁' l₂', l = l₁' ++ l₂' l₁ = l₁'.enum l₂ = l₂'.enumFrom l₁'.length := by
simp [enum, enumFrom_eq_append_iff]
end List

View File

@@ -42,7 +42,7 @@ theorem getElem_take' (L : List α) {i j : Nat} (hi : i < L.length) (hj : i < j)
/-- The `i`-th element of a list coincides with the `i`-th element of any of its prefixes of
length `> i`. Version designed to rewrite from the small list to the big list. -/
@[simp] theorem getElem_take (L : List α) {j i : Nat} {h : i < (L.take j).length} :
theorem getElem_take (L : List α) {j i : Nat} {h : i < (L.take j).length} :
(L.take j)[i] =
L[i]'(Nat.lt_of_lt_of_le h (length_take_le' _ _)) := by
rw [length_take, Nat.lt_min] at h; rw [getElem_take' L _ h.1]
@@ -52,7 +52,7 @@ length `> i`. Version designed to rewrite from the big list to the small list. -
@[deprecated getElem_take' (since := "2024-06-12")]
theorem get_take (L : List α) {i j : Nat} (hi : i < L.length) (hj : i < j) :
get L i, hi = get (L.take j) i, length_take .. Nat.lt_min.mpr hj, hi := by
simp
simp [getElem_take' _ hi hj]
/-- The `i`-th element of a list coincides with the `i`-th element of any of its prefixes of
length `> i`. Version designed to rewrite from the small list to the big list. -/
@@ -187,9 +187,6 @@ theorem take_add (l : List α) (m n : Nat) : l.take (m + n) = l.take m ++ (l.dro
· apply length_take_le
· apply Nat.le_add_right
theorem take_one {l : List α} : l.take 1 = l.head?.toList := by
induction l <;> simp
theorem dropLast_take {n : Nat} {l : List α} (h : n < l.length) :
(l.take n).dropLast = l.take (n - 1) := by
simp only [dropLast_eq_take, length_take, Nat.le_of_lt h, Nat.min_eq_left, take_take, sub_le]
@@ -285,14 +282,14 @@ theorem mem_drop_iff_getElem {l : List α} {a : α} :
· rintro i, hm, rfl
refine i, by simp; omega, by rw [getElem_drop]
@[simp] theorem head?_drop (l : List α) (n : Nat) :
theorem head?_drop (l : List α) (n : Nat) :
(l.drop n).head? = l[n]? := by
rw [head?_eq_getElem?, getElem?_drop, Nat.add_zero]
@[simp] theorem head_drop {l : List α} {n : Nat} (h : l.drop n []) :
theorem head_drop {l : List α} {n : Nat} (h : l.drop n []) :
(l.drop n).head h = l[n]'(by simp_all) := by
have w : n < l.length := length_lt_of_drop_ne_nil h
simp [getElem?_eq_getElem, h, w, head_eq_iff_head?_eq_some]
simpa [getElem?_eq_getElem, h, w, head_eq_iff_head?_eq_some] using head?_drop l n
theorem getLast?_drop {l : List α} : (l.drop n).getLast? = if l.length n then none else l.getLast? := by
rw [getLast?_eq_getElem?, getElem?_drop]
@@ -303,7 +300,7 @@ theorem getLast?_drop {l : List α} : (l.drop n).getLast? = if l.length ≤ n th
congr
omega
@[simp] theorem getLast_drop {l : List α} (h : l.drop n []) :
theorem getLast_drop {l : List α} (h : l.drop n []) :
(l.drop n).getLast h = l.getLast (ne_nil_of_length_pos (by simp at h; omega)) := by
simp only [ne_eq, drop_eq_nil_iff] at h
apply Option.some_inj.1
@@ -452,26 +449,6 @@ theorem reverse_drop {l : List α} {n : Nat} :
rw [w, take_zero, drop_of_length_le, reverse_nil]
omega
theorem take_add_one {l : List α} {n : Nat} :
l.take (n + 1) = l.take n ++ l[n]?.toList := by
simp [take_add, take_one]
theorem drop_eq_getElem?_toList_append {l : List α} {n : Nat} :
l.drop n = l[n]?.toList ++ l.drop (n + 1) := by
induction l generalizing n with
| nil => simp
| cons hd tl ih =>
cases n
· simp
· simp only [drop_succ_cons, getElem?_cons_succ]
rw [ih]
theorem drop_sub_one {l : List α} {n : Nat} (h : 0 < n) :
l.drop (n - 1) = l[n - 1]?.toList ++ l.drop n := by
rw [drop_eq_getElem?_toList_append]
congr
omega
/-! ### findIdx -/
theorem false_of_mem_take_findIdx {xs : List α} {p : α Bool} (h : x xs.take (xs.findIdx p)) :

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

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@@ -76,11 +76,11 @@ theorem pairwise_of_forall {l : List α} (H : ∀ x y, R x y) : Pairwise R l :=
theorem Pairwise.and_mem {l : List α} :
Pairwise R l Pairwise (fun x y => x l y l R x y) l :=
Pairwise.iff_of_mem <| by simp +contextual
Pairwise.iff_of_mem <| by simp (config := { contextual := true })
theorem Pairwise.imp_mem {l : List α} :
Pairwise R l Pairwise (fun x y => x l y l R x y) l :=
Pairwise.iff_of_mem <| by simp +contextual
Pairwise.iff_of_mem <| by simp (config := { contextual := true })
theorem Pairwise.forall_of_forall_of_flip (h₁ : x l, R x x) (h₂ : Pairwise R l)
(h₃ : l.Pairwise (flip R)) : x, x l y, y l R x y := by
@@ -160,25 +160,21 @@ theorem pairwise_middle {R : αα → Prop} (s : ∀ {x y}, R x y → R y x
rw [ append_assoc, pairwise_append, @pairwise_append _ _ ([a] ++ l₁), pairwise_append_comm s]
simp only [mem_append, or_comm]
theorem pairwise_flatten {L : List (List α)} :
Pairwise R (flatten L)
theorem pairwise_join {L : List (List α)} :
Pairwise R (join L)
( l L, Pairwise R l) Pairwise (fun l₁ l₂ => x l₁, y l₂, R x y) L := by
induction L with
| nil => simp
| cons l L IH =>
simp only [flatten, pairwise_append, IH, mem_flatten, exists_imp, and_imp, forall_mem_cons,
simp only [join, pairwise_append, IH, mem_join, exists_imp, and_imp, forall_mem_cons,
pairwise_cons, and_assoc, and_congr_right_iff]
rw [and_comm, and_congr_left_iff]
intros; exact fun h a b c d e => h c d e a b, fun h c d e a b => h a b c d e
@[deprecated pairwise_flatten (since := "2024-10-14")] abbrev pairwise_join := @pairwise_flatten
theorem pairwise_flatMap {R : β β Prop} {l : List α} {f : α List β} :
List.Pairwise R (l.flatMap f)
theorem pairwise_bind {R : β β Prop} {l : List α} {f : α List β} :
List.Pairwise R (l.bind f)
( a l, Pairwise R (f a)) Pairwise (fun a₁ a₂ => x f a₁, y f a₂, R x y) l := by
simp [List.flatMap, pairwise_flatten, pairwise_map]
@[deprecated pairwise_flatMap (since := "2024-10-14")] abbrev pairwise_bind := @pairwise_flatMap
simp [List.bind, pairwise_join, pairwise_map]
theorem pairwise_reverse {l : List α} :
l.reverse.Pairwise R l.Pairwise (fun a b => R b a) := by

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@@ -98,8 +98,8 @@ theorem Perm.append_cons (a : α) {h₁ h₂ t₁ t₂ : List α} (p₁ : h₁ ~
perm_middle.trans <| by rw [append_nil]
theorem perm_append_comm : {l₁ l₂ : List α}, l₁ ++ l₂ ~ l₂ ++ l₁
| [], _ => by simp
| _ :: _, _ => (perm_append_comm.cons _).trans perm_middle.symm
| [], l₂ => by simp
| a :: t, l₂ => (perm_append_comm.cons _).trans perm_middle.symm
theorem perm_append_comm_assoc (l₁ l₂ l₃ : List α) :
Perm (l₁ ++ (l₂ ++ l₃)) (l₂ ++ (l₁ ++ l₃)) := by
@@ -248,10 +248,6 @@ theorem countP_eq_countP_filter_add (l : List α) (p q : α → Bool) :
theorem Perm.count_eq [DecidableEq α] {l₁ l₂ : List α} (p : l₁ ~ l₂) (a) :
count a l₁ = count a l₂ := p.countP_eq _
/-
This theorem is a variant of `Perm.foldl_eq` defined in Mathlib which uses typeclasses rather
than the explicit `comm` argument.
-/
theorem Perm.foldl_eq' {f : β α β} {l₁ l₂ : List α} (p : l₁ ~ l₂)
(comm : x l₁, y l₁, (z), f (f z x) y = f (f z y) x)
(init) : foldl f init l₁ = foldl f init l₂ := by
@@ -268,28 +264,6 @@ theorem Perm.foldl_eq' {f : β → α → β} {l₁ l₂ : List α} (p : l₁ ~
refine (IH₁ comm init).trans (IH₂ ?_ _)
intros; apply comm <;> apply p₁.symm.subset <;> assumption
/-
This theorem is a variant of `Perm.foldr_eq` defined in Mathlib which uses typeclasses rather
than the explicit `comm` argument.
-/
theorem Perm.foldr_eq' {f : α β β} {l₁ l₂ : List α} (p : l₁ ~ l₂)
(comm : x l₁, y l₁, (z), f y (f x z) = f x (f y z))
(init) : foldr f init l₁ = foldr f init l₂ := by
induction p using recOnSwap' generalizing init with
| nil => simp
| cons x _p IH =>
simp only [foldr]
congr 1
apply IH; intros; apply comm <;> exact .tail _ _
| swap' x y _p IH =>
simp only [foldr]
rw [comm x (.tail _ <| .head _) y (.head _)]
congr 2
apply IH; intros; apply comm <;> exact .tail _ (.tail _ _)
| trans p₁ _p₂ IH₁ IH₂ =>
refine (IH₁ comm init).trans (IH₂ ?_ _)
intros; apply comm <;> apply p₁.symm.subset <;> assumption
theorem Perm.rec_heq {β : List α Sort _} {f : a l, β l β (a :: l)} {b : β []} {l l' : List α}
(hl : l ~ l') (f_congr : {a l l' b b'}, l ~ l' HEq b b' HEq (f a l b) (f a l' b'))
(f_swap : {a a' l b}, HEq (f a (a' :: l) (f a' l b)) (f a' (a :: l) (f a l b))) :
@@ -461,19 +435,15 @@ theorem Perm.nodup {l l' : List α} (hl : l ~ l') (hR : l.Nodup) : l'.Nodup := h
theorem Perm.nodup_iff {l₁ l₂ : List α} : l₁ ~ l₂ (Nodup l₁ Nodup l₂) :=
Perm.pairwise_iff <| @Ne.symm α
theorem Perm.flatten {l₁ l₂ : List (List α)} (h : l₁ ~ l₂) : l₁.flatten ~ l₂.flatten := by
theorem Perm.join {l₁ l₂ : List (List α)} (h : l₁ ~ l₂) : l₁.join ~ l₂.join := by
induction h with
| nil => rfl
| cons _ _ ih => simp only [flatten_cons, perm_append_left_iff, ih]
| swap => simp only [flatten_cons, append_assoc, perm_append_right_iff]; exact perm_append_comm ..
| cons _ _ ih => simp only [join_cons, perm_append_left_iff, ih]
| swap => simp only [join_cons, append_assoc, perm_append_right_iff]; exact perm_append_comm ..
| trans _ _ ih₁ ih₂ => exact trans ih₁ ih₂
@[deprecated Perm.flatten (since := "2024-10-14")] abbrev Perm.join := @Perm.flatten
theorem Perm.flatMap_right {l₁ l₂ : List α} (f : α List β) (p : l₁ ~ l₂) : l₁.flatMap f ~ l₂.flatMap f :=
(p.map _).flatten
@[deprecated Perm.flatMap_right (since := "2024-10-16")] abbrev Perm.bind_right := @Perm.flatMap_right
theorem Perm.bind_right {l₁ l₂ : List α} (f : α List β) (p : l₁ ~ l₂) : l₁.bind f ~ l₂.bind f :=
(p.map _).join
theorem Perm.eraseP (f : α Bool) {l₁ l₂ : List α}
(H : Pairwise (fun a b => f a f b False) l₁) (p : l₁ ~ l₂) : eraseP f l₁ ~ eraseP f l₂ := by

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@@ -20,6 +20,7 @@ open Nat
/-! ## Ranges and enumeration -/
/-! ### range' -/
theorem range'_succ (s n step) : range' s (n + 1) step = s :: range' (s + step) n step := by
@@ -91,7 +92,7 @@ theorem map_add_range' (a) : ∀ s n step, map (a + ·) (range' s n step) = rang
theorem range'_append : s m n step : Nat,
range' s m step ++ range' (s + step * m) n step = range' s (n + m) step
| _, 0, _, _ => rfl
| s, 0, n, step => rfl
| s, m + 1, n, step => by
simpa [range', Nat.mul_succ, Nat.add_assoc, Nat.add_comm]
using range'_append (s + step) m n step
@@ -130,7 +131,7 @@ theorem range'_eq_cons_iff : range' s n = a :: xs ↔ s = a ∧ 0 < n ∧ xs = r
/-! ### range -/
theorem range_loop_range' : s n : Nat, range.loop s (range' s n) = range' 0 (n + s)
| 0, _ => rfl
| 0, n => rfl
| s + 1, n => by rw [ Nat.add_assoc, Nat.add_right_comm n s 1]; exact range_loop_range' s (n + 1)
theorem range_eq_range' (n : Nat) : range n = range' 0 n :=
@@ -213,9 +214,9 @@ theorem enumFrom_eq_nil {n : Nat} {l : List α} : List.enumFrom n l = [] ↔ l =
@[simp]
theorem getElem?_enumFrom :
n (l : List α) m, (enumFrom n l)[m]? = l[m]?.map fun a => (n + m, a)
| _, [], _ => rfl
| _, _ :: _, 0 => by simp
| n, _ :: l, m + 1 => by
| n, [], m => rfl
| n, a :: l, 0 => by simp
| n, a :: l, m + 1 => by
simp only [enumFrom_cons, getElem?_cons_succ]
exact (getElem?_enumFrom (n + 1) l m).trans <| by rw [Nat.add_right_comm]; rfl

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@@ -102,7 +102,7 @@ def mergeSortTR (l : List α) (le : αα → Bool := by exact fun a b => a
where run : {n : Nat} { l : List α // l.length = n } List α
| 0, [], _ => []
| 1, [a], _ => [a]
| _+2, xs =>
| n+2, xs =>
let (l, r) := splitInTwo xs
mergeTR (run l) (run r) le
@@ -136,13 +136,13 @@ where
run : {n : Nat} { l : List α // l.length = n } List α
| 0, [], _ => []
| 1, [a], _ => [a]
| _+2, xs =>
| n+2, xs =>
let (l, r) := splitRevInTwo xs
mergeTR (run' l) (run r) le
run' : {n : Nat} { l : List α // l.length = n } List α
| 0, [], _ => []
| 1, [a], _ => [a]
| _+2, xs =>
| n+2, xs =>
let (l, r) := splitRevInTwo' xs
mergeTR (run' r) (run l) le

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@@ -116,7 +116,7 @@ fun s => Subset.trans s <| subset_append_right _ _
theorem replicate_subset {n : Nat} {a : α} {l : List α} : replicate n a l n = 0 a l := by
induction n with
| zero => simp
| succ n ih => simp +contextual [replicate_succ, ih, cons_subset]
| succ n ih => simp (config := {contextual := true}) [replicate_succ, ih, cons_subset]
theorem subset_replicate {n : Nat} {a : α} {l : List α} (h : n 0) : l replicate n a x l, x = a := by
induction l with
@@ -483,30 +483,30 @@ theorem sublist_replicate_iff : l <+ replicate m a ↔ ∃ n, n ≤ m ∧ l = re
rw [w]
exact (replicate_sublist_replicate a).2 le
theorem sublist_flatten_of_mem {L : List (List α)} {l} (h : l L) : l <+ L.flatten := by
theorem sublist_join_of_mem {L : List (List α)} {l} (h : l L) : l <+ L.join := by
induction L with
| nil => cases h
| cons l' L ih =>
rcases mem_cons.1 h with (rfl | h)
· simp [h]
· simp [ih h, flatten_cons, sublist_append_of_sublist_right]
· simp [ih h, join_cons, sublist_append_of_sublist_right]
theorem sublist_flatten_iff {L : List (List α)} {l} :
l <+ L.flatten
L' : List (List α), l = L'.flatten i (_ : i < L'.length), L'[i] <+ L[i]?.getD [] := by
theorem sublist_join_iff {L : List (List α)} {l} :
l <+ L.join
L' : List (List α), l = L'.join i (_ : i < L'.length), L'[i] <+ L[i]?.getD [] := by
induction L generalizing l with
| nil =>
constructor
· intro w
simp only [flatten_nil, sublist_nil] at w
simp only [join_nil, sublist_nil] at w
subst w
exact [], by simp, fun i x => by cases x
· rintro L', rfl, h
simp only [flatten_nil, sublist_nil, flatten_eq_nil_iff]
simp only [join_nil, sublist_nil, join_eq_nil_iff]
simp only [getElem?_nil, Option.getD_none, sublist_nil] at h
exact (forall_getElem (p := (· = []))).1 h
| cons l' L ih =>
simp only [flatten_cons, sublist_append_iff, ih]
simp only [join_cons, sublist_append_iff, ih]
constructor
· rintro l₁, l₂, rfl, s, L', rfl, h
refine l₁ :: L', by simp, ?_
@@ -517,21 +517,21 @@ theorem sublist_flatten_iff {L : List (List α)} {l} :
| nil =>
exact [], [], by simp, by simp, [], by simp, fun i x => by cases x
| cons l₁ L' =>
exact l₁, L'.flatten, by simp, by simpa using h 0 (by simp), L', rfl,
exact l₁, L'.join, by simp, by simpa using h 0 (by simp), L', rfl,
fun i lt => by simpa using h (i+1) (Nat.add_lt_add_right lt 1)
theorem flatten_sublist_iff {L : List (List α)} {l} :
L.flatten <+ l
L' : List (List α), l = L'.flatten i (_ : i < L.length), L[i] <+ L'[i]?.getD [] := by
theorem join_sublist_iff {L : List (List α)} {l} :
L.join <+ l
L' : List (List α), l = L'.join i (_ : i < L.length), L[i] <+ L'[i]?.getD [] := by
induction L generalizing l with
| nil =>
constructor
· intro _
exact [l], by simp, fun i x => by cases x
· rintro L', rfl, _
simp only [flatten_nil, nil_sublist]
simp only [join_nil, nil_sublist]
| cons l' L ih =>
simp only [flatten_cons, append_sublist_iff, ih]
simp only [join_cons, append_sublist_iff, ih]
constructor
· rintro l₁, l₂, rfl, s, L', rfl, h
refine l₁ :: L', by simp, ?_
@@ -543,7 +543,7 @@ theorem flatten_sublist_iff {L : List (List α)} {l} :
exact [], [], by simp, by simpa using h 0 (by simp), [], by simp,
fun i x => by simpa using h (i+1) (Nat.add_lt_add_right x 1)
| cons l₁ L' =>
exact l₁, L'.flatten, by simp, by simpa using h 0 (by simp), L', rfl,
exact l₁, L'.join, by simp, by simpa using h 0 (by simp), L', rfl,
fun i lt => by simpa using h (i+1) (Nat.add_lt_add_right lt 1)
@[simp] theorem isSublist_iff_sublist [BEq α] [LawfulBEq α] {l₁ l₂ : List α} :
@@ -725,25 +725,16 @@ theorem infix_iff_suffix_prefix {l₁ l₂ : List α} : l₁ <:+: l₂ ↔ ∃ t
theorem IsInfix.eq_of_length (h : l₁ <:+: l₂) : l₁.length = l₂.length l₁ = l₂ :=
h.sublist.eq_of_length
theorem IsInfix.eq_of_length_le (h : l₁ <:+: l₂) : l₂.length l₁.length l₁ = l₂ :=
h.sublist.eq_of_length_le
theorem IsPrefix.eq_of_length (h : l₁ <+: l₂) : l₁.length = l₂.length l₁ = l₂ :=
h.sublist.eq_of_length
theorem IsPrefix.eq_of_length_le (h : l₁ <+: l₂) : l₂.length l₁.length l₁ = l₂ :=
h.sublist.eq_of_length_le
theorem IsSuffix.eq_of_length (h : l₁ <:+ l₂) : l₁.length = l₂.length l₁ = l₂ :=
h.sublist.eq_of_length
theorem IsSuffix.eq_of_length_le (h : l₁ <:+ l₂) : l₂.length l₁.length l₁ = l₂ :=
h.sublist.eq_of_length_le
theorem prefix_of_prefix_length_le :
{l₁ l₂ l₃ : List α}, l₁ <+: l₃ l₂ <+: l₃ length l₁ length l₂ l₁ <+: l₂
| [], _, _, _, _, _ => nil_prefix
| _ :: _, b :: _, _, _, rfl, _, e, ll => by
| [], l₂, _, _, _, _ => nil_prefix
| a :: l₁, b :: l₂, _, r₁, rfl, r₂, e, ll => by
injection e with _ e'; subst b
rcases prefix_of_prefix_length_le _, rfl _, e' (le_of_succ_le_succ ll) with r₃, rfl
exact r₃, rfl
@@ -835,27 +826,9 @@ theorem isPrefix_iff : l₁ <+: l₂ ↔ ∀ i (h : i < l₁.length), l₂[i]? =
simpa using 0, by simp
| cons b l₂ =>
simp only [cons_append, cons_prefix_cons, ih]
rw (occs := .pos [2]) [ Nat.and_forall_add_one]
rw (config := {occs := .pos [2]}) [ Nat.and_forall_add_one]
simp [Nat.succ_lt_succ_iff, eq_comm]
theorem isPrefix_iff_getElem {l₁ l₂ : List α} :
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.getElem _
mpr h := by
obtain hl, h := h
induction l₂ generalizing l₁ with
| nil =>
simpa using hl
| cons _ _ tail_ih =>
cases l₁ with
| nil =>
exact nil_prefix
| cons _ _ =>
simp only [length_cons, Nat.add_le_add_iff_right, Fin.getElem_fin] at hl h
simp only [cons_prefix_cons]
exact h 0 (zero_lt_succ _), tail_ih hl fun a ha h a.succ (succ_lt_succ ha)
-- See `Init.Data.List.Nat.Sublist` for `isSuffix_iff` and `ifInfix_iff`.
theorem isPrefix_filterMap_iff {β} {f : α Option β} {l₁ : List α} {l₂ : List β} :
@@ -938,14 +911,14 @@ theorem isInfix_replicate_iff {n} {a : α} {l : List α} :
· simpa using Nat.sub_add_cancel h
· simpa using w
theorem infix_of_mem_flatten : {L : List (List α)}, l L l <:+: flatten L
theorem infix_of_mem_join : {L : List (List α)}, l L l <:+: join L
| l' :: _, h =>
match h with
| List.Mem.head .. => infix_append [] _ _
| List.Mem.tail _ hlMemL =>
IsInfix.trans (infix_of_mem_flatten hlMemL) <| (suffix_append _ _).isInfix
IsInfix.trans (infix_of_mem_join hlMemL) <| (suffix_append _ _).isInfix
@[simp] theorem prefix_append_right_inj (l) : l ++ l₁ <+: l ++ l₂ l₁ <+: l₂ :=
theorem prefix_append_right_inj (l) : l ++ l₁ <+: l ++ l₂ l₁ <+: l₂ :=
exists_congr fun r => by rw [append_assoc, append_right_inj]
theorem prefix_cons_inj (a) : a :: l₁ <+: a :: l₂ l₁ <+: l₂ :=
@@ -976,7 +949,7 @@ theorem mem_of_mem_drop {n} {l : List α} (h : a ∈ l.drop n) : a ∈ l :=
drop_subset _ _ h
theorem drop_suffix_drop_left (l : List α) {m n : Nat} (h : m n) : drop n l <:+ drop m l := by
rw [ Nat.sub_add_cancel h, Nat.add_comm, drop_drop]
rw [ Nat.sub_add_cancel h, drop_drop]
apply drop_suffix
-- See `Init.Data.List.Nat.TakeDrop` for `take_prefix_take_left`.
@@ -1087,11 +1060,4 @@ theorem prefix_iff_eq_take : l₁ <+: l₂ ↔ l₁ = take (length l₁) l₂ :=
-- See `Init.Data.List.Nat.Sublist` for `suffix_iff_eq_append`, `prefix_take_iff`, and `suffix_iff_eq_drop`.
/-! ### Deprecations -/
@[deprecated sublist_flatten_of_mem (since := "2024-10-14")] abbrev sublist_join_of_mem := @sublist_flatten_of_mem
@[deprecated sublist_flatten_iff (since := "2024-10-14")] abbrev sublist_join_iff := @sublist_flatten_iff
@[deprecated flatten_sublist_iff (since := "2024-10-14")] abbrev flatten_join_iff := @flatten_sublist_iff
@[deprecated infix_of_mem_flatten (since := "2024-10-14")] abbrev infix_of_mem_join := @infix_of_mem_flatten
end List

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@@ -97,14 +97,14 @@ theorem get?_take {l : List α} {n m : Nat} (h : m < n) : (l.take n).get? m = l.
theorem getElem?_take_of_succ {l : List α} {n : Nat} : (l.take (n + 1))[n]? = l[n]? := by simp
@[simp] theorem drop_drop (n : Nat) : (m) (l : List α), drop n (drop m l) = drop (m + n) l
@[simp] theorem drop_drop (n : Nat) : (m) (l : List α), drop n (drop m l) = drop (n + m) l
| m, [] => by simp
| 0, l => by simp
| m + 1, a :: l =>
calc
drop n (drop (m + 1) (a :: l)) = drop n (drop m l) := rfl
_ = drop (m + n) l := drop_drop n m l
_ = drop ((m + 1) + n) (a :: l) := by rw [Nat.add_right_comm]; rfl
_ = drop (n + m) l := drop_drop n m l
_ = drop (n + (m + 1)) (a :: l) := rfl
theorem take_drop : (m n : Nat) (l : List α), take n (drop m l) = drop m (take (m + n) l)
| 0, _, _ => by simp
@@ -112,7 +112,7 @@ theorem take_drop : ∀ (m n : Nat) (l : List α), take n (drop m l) = drop m (t
| _+1, _, _ :: _ => by simpa [Nat.succ_add, take_succ_cons, drop_succ_cons] using take_drop ..
@[deprecated drop_drop (since := "2024-06-15")]
theorem drop_add (m n) (l : List α) : drop (m + n) l = drop n (drop m l) := by
theorem drop_add (m n) (l : List α) : drop (m + n) l = drop m (drop n l) := by
simp [drop_drop]
@[simp]
@@ -126,7 +126,7 @@ theorem tail_drop (l : List α) (n : Nat) : (l.drop n).tail = l.drop (n + 1) :=
@[simp]
theorem drop_tail (l : List α) (n : Nat) : l.tail.drop n = l.drop (n + 1) := by
rw [Nat.add_comm, drop_drop, drop_one]
rw [ drop_drop, drop_one]
@[simp]
theorem drop_eq_nil_iff {l : List α} {k : Nat} : l.drop k = [] l.length k := by
@@ -190,7 +190,7 @@ theorem set_drop {l : List α} {n m : Nat} {a : α} :
theorem take_concat_get (l : List α) (i : Nat) (h : i < l.length) :
(l.take i).concat l[i] = l.take (i+1) :=
Eq.symm <| (append_left_inj _).1 <| (take_append_drop (i+1) l).trans <| by
rw [concat_eq_append, append_assoc, singleton_append, getElem_cons_drop_succ_eq_drop, take_append_drop]
rw [concat_eq_append, append_assoc, singleton_append, get_drop_eq_drop, take_append_drop]
@[deprecated take_succ_cons (since := "2024-07-25")]
theorem take_cons_succ : (a::as).take (i+1) = a :: as.take i := rfl

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@@ -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)

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@@ -5,7 +5,6 @@ Authors: Parikshit Khanna, Jeremy Avigad, Leonardo de Moura, Floris van Doorn, M
-/
prelude
import Init.Data.List.TakeDrop
import Init.Data.Function
/-!
# Lemmas about `List.zip`, `List.zipWith`, `List.zipWithAll`, and `List.unzip`.
@@ -239,14 +238,6 @@ theorem zipWith_eq_append_iff {f : α → β → γ} {l₁ : List α} {l₂ : Li
| zero => rfl
| succ n ih => simp [replicate_succ, ih]
theorem map_uncurry_zip_eq_zipWith (f : α β γ) (l : List α) (l' : List β) :
map (Function.uncurry f) (l.zip l') = zipWith f l l' := by
rw [zip]
induction l generalizing l' with
| nil => simp
| cons hl tl ih =>
cases l' <;> simp [ih]
/-! ### zip -/
theorem zip_eq_zipWith : (l₁ : List α) (l₂ : List β), zip l₁ l₂ = zipWith Prod.mk l₁ l₂
@@ -256,9 +247,9 @@ theorem zip_eq_zipWith : ∀ (l₁ : List α) (l₂ : List β), zip l₁ l₂ =
theorem zip_map (f : α γ) (g : β δ) :
(l₁ : List α) (l₂ : List β), zip (l₁.map f) (l₂.map g) = (zip l₁ l₂).map (Prod.map f g)
| [], _ => rfl
| _, [] => by simp only [map, zip_nil_right]
| _ :: _, _ :: _ => by
| [], l₂ => rfl
| l₁, [] => by simp only [map, zip_nil_right]
| a :: l₁, b :: l₂ => by
simp only [map, zip_cons_cons, zip_map, Prod.map]; constructor
theorem zip_map_left (f : α γ) (l₁ : List α) (l₂ : List β) :
@@ -296,12 +287,12 @@ theorem of_mem_zip {a b} : ∀ {l₁ : List α} {l₂ : List β}, (a, b) ∈ zip
theorem map_fst_zip :
(l₁ : List α) (l₂ : List β), l₁.length l₂.length map Prod.fst (zip l₁ l₂) = l₁
| [], _, _ => rfl
| [], bs, _ => rfl
| _ :: as, _ :: bs, h => by
simp [Nat.succ_le_succ_iff] at h
show _ :: map Prod.fst (zip as bs) = _ :: as
rw [map_fst_zip as bs h]
| _ :: _, [], h => by simp at h
| a :: as, [], h => by simp at h
theorem map_snd_zip :
(l₁ : List α) (l₂ : List β), l₂.length l₁.length map Prod.snd (zip l₁ l₂) = l₂
@@ -439,9 +430,9 @@ theorem zip_unzip : ∀ l : List (α × β), zip (unzip l).1 (unzip l).2 = l
theorem unzip_zip_left :
{l₁ : List α} {l₂ : List β}, length l₁ length l₂ (unzip (zip l₁ l₂)).1 = l₁
| [], _, _ => rfl
| _, [], h => by rw [eq_nil_of_length_eq_zero (Nat.eq_zero_of_le_zero h)]; rfl
| _ :: _, _ :: _, h => by
| [], l₂, _ => rfl
| l₁, [], h => by rw [eq_nil_of_length_eq_zero (Nat.eq_zero_of_le_zero h)]; rfl
| a :: l₁, b :: l₂, h => by
simp only [zip_cons_cons, unzip_cons, unzip_zip_left (le_of_succ_le_succ h)]
theorem unzip_zip_right :

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@@ -131,7 +131,7 @@ theorem or_exists_add_one : p 0 (Exists fun n => p (n + 1)) ↔ Exists p :=
@[simp] theorem blt_eq : (Nat.blt x y = true) = (x < y) := propext <| Iff.intro Nat.le_of_ble_eq_true Nat.ble_eq_true_of_le
instance : LawfulBEq Nat where
eq_of_beq h := by simpa using h
eq_of_beq h := Nat.eq_of_beq_eq_true h
rfl := by simp [BEq.beq]
theorem beq_eq_true_eq (a b : Nat) : ((a == b) = true) = (a = b) := by simp
@@ -248,7 +248,7 @@ protected theorem add_mul (n m k : Nat) : (n + m) * k = n * k + m * k :=
Nat.right_distrib n m k
protected theorem mul_assoc : (n m k : Nat), (n * m) * k = n * (m * k)
| _, _, 0 => rfl
| n, m, 0 => rfl
| n, m, succ k => by simp [mul_succ, Nat.mul_assoc n m k, Nat.left_distrib]
instance : Std.Associative (α := Nat) (· * ·) := Nat.mul_assoc
@@ -490,10 +490,10 @@ protected theorem le_antisymm_iff {a b : Nat} : a = b ↔ a ≤ b ∧ b ≤ a :=
(fun hle, hge => Nat.le_antisymm hle hge)
protected theorem eq_iff_le_and_ge : {a b : Nat}, a = b a b b a := @Nat.le_antisymm_iff
instance : Std.Antisymm ( . . : Nat Nat Prop) where
instance : Antisymm ( . . : Nat Nat Prop) where
antisymm h₁ h₂ := Nat.le_antisymm h₁ h₂
instance : Std.Antisymm (¬ . < . : Nat Nat Prop) where
instance : Antisymm (¬ . < . : Nat Nat Prop) where
antisymm h₁ h₂ := Nat.le_antisymm (Nat.ge_of_not_lt h₂) (Nat.ge_of_not_lt h₁)
protected theorem add_le_add_left {n m : Nat} (h : n m) (k : Nat) : k + n k + m :=
@@ -634,8 +634,6 @@ theorem lt_succ_of_lt (h : a < b) : a < succ b := le_succ_of_le h
theorem lt_add_one_of_lt (h : a < b) : a < b + 1 := le_succ_of_le h
@[simp] theorem lt_one_iff : n < 1 n = 0 := Nat.lt_succ_iff.trans <| by rw [le_zero_eq]
theorem succ_pred_eq_of_ne_zero : {n}, n 0 succ (pred n) = n
| _+1, _ => rfl
@@ -796,8 +794,6 @@ theorem pos_pow_of_pos {n : Nat} (m : Nat) (h : 0 < n) : 0 < n^m :=
| zero => cases h
| succ n => simp [Nat.pow_succ]
protected theorem two_pow_pos (w : Nat) : 0 < 2^w := Nat.pos_pow_of_pos _ (by decide)
instance {n m : Nat} [NeZero n] : NeZero (n^m) :=
Nat.ne_zero_iff_zero_lt.mpr (Nat.pos_pow_of_pos m (pos_of_neZero _))

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@@ -269,7 +269,7 @@ protected theorem div_div_eq_div_mul (m n k : Nat) : m / n / k = m / (n * k) :=
theorem div_mul_le_self : (m n : Nat), m / n * n m
| m, 0 => by simp
| _, _+1 => (le_div_iff_mul_le (Nat.succ_pos _)).1 (Nat.le_refl _)
| m, n+1 => (le_div_iff_mul_le (Nat.succ_pos _)).1 (Nat.le_refl _)
theorem div_lt_iff_lt_mul (Hk : 0 < k) : x / k < y x < y * k := by
rw [ Nat.not_le, Nat.not_le]; exact not_congr (le_div_iff_mul_le Hk)

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

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@@ -32,77 +32,6 @@ namespace Nat
@[simp] theorem exists_add_one_eq : ( n, n + 1 = a) 0 < a :=
fun n, h => by omega, fun h => a - 1, by omega
/-- Dependent variant of `forall_lt_succ_right`. -/
theorem forall_lt_succ_right' {p : (m : Nat) (m < n + 1) Prop} :
( m (h : m < n + 1), p m h) ( m (h : m < n), p m (by omega)) p n (by omega) := by
simp only [Nat.lt_succ_iff, Nat.le_iff_lt_or_eq]
constructor
· intro w
constructor
· intro m h
exact w _ (.inl h)
· exact w _ (.inr rfl)
· rintro w m (h|rfl)
· exact w.1 _ h
· exact w.2
/-- See `forall_lt_succ_right'` for a variant where `p` takes the bound as an argument. -/
theorem forall_lt_succ_right {p : Nat Prop} :
( m, m < n + 1 p m) ( m, m < n p m) p n := by
simpa using forall_lt_succ_right' (p := fun m _ => p m)
/-- Dependent variant of `forall_lt_succ_left`. -/
theorem forall_lt_succ_left' {p : (m : Nat) (m < n + 1) Prop} :
( m (h : m < n + 1), p m h) p 0 (by omega) ( m (h : m < n), p (m + 1) (by omega)) := by
constructor
· intro w
constructor
· exact w 0 (by omega)
· intro m h
exact w (m + 1) (by omega)
· rintro h₀, h₁ m h
cases m with
| zero => exact h₀
| succ m => exact h₁ m (by omega)
/-- See `forall_lt_succ_left'` for a variant where `p` takes the bound as an argument. -/
theorem forall_lt_succ_left {p : Nat Prop} :
( m, m < n + 1 p m) p 0 ( m, m < n p (m + 1)) := by
simpa using forall_lt_succ_left' (p := fun m _ => p m)
/-- Dependent variant of `exists_lt_succ_right`. -/
theorem exists_lt_succ_right' {p : (m : Nat) (m < n + 1) Prop} :
( m, (h : m < n + 1), p m h) ( m, (h : m < n), p m (by omega)) p n (by omega) := by
simp only [Nat.lt_succ_iff, Nat.le_iff_lt_or_eq]
constructor
· rintro m, (h|rfl), w
· exact .inl m, h, w
· exact .inr w
· rintro (m, h, w | w)
· exact m, by omega, w
· exact n, by omega, w
/-- See `exists_lt_succ_right'` for a variant where `p` takes the bound as an argument. -/
theorem exists_lt_succ_right {p : Nat Prop} :
( m, m < n + 1 p m) ( m, m < n p m) p n := by
simpa using exists_lt_succ_right' (p := fun m _ => p m)
/-- Dependent variant of `exists_lt_succ_left`. -/
theorem exists_lt_succ_left' {p : (m : Nat) (m < n + 1) Prop} :
( m, (h : m < n + 1), p m h) p 0 (by omega) ( m, (h : m < n), p (m + 1) (by omega)) := by
constructor
· rintro _|m, h, w
· exact .inl w
· exact .inr m, by omega, w
· rintro (w|m, h, w)
· exact 0, by omega, w
· exact m + 1, by omega, w
/-- See `exists_lt_succ_left'` for a variant where `p` takes the bound as an argument. -/
theorem exists_lt_succ_left {p : Nat Prop} :
( m, m < n + 1 p m) p 0 ( m, m < n p (m + 1)) := by
simpa using exists_lt_succ_left' (p := fun m _ => p m)
/-! ## add -/
protected theorem add_add_add_comm (a b c d : Nat) : (a + b) + (c + d) = (a + c) + (b + d) := by
@@ -651,8 +580,8 @@ theorem sub_mul_mod {x k n : Nat} (h₁ : n*k ≤ x) : (x - n*k) % n = x % n :=
| .inr npos => Nat.mod_eq_of_lt (mod_lt _ npos)
theorem mul_mod (a b n : Nat) : a * b % n = (a % n) * (b % n) % n := by
rw (occs := .pos [1]) [ mod_add_div a n]
rw (occs := .pos [1]) [ mod_add_div b n]
rw (config := {occs := .pos [1]}) [ mod_add_div a n]
rw (config := {occs := .pos [1]}) [ mod_add_div b n]
rw [Nat.add_mul, Nat.mul_add, Nat.mul_add,
Nat.mul_assoc, Nat.mul_assoc, Nat.mul_add n, add_mul_mod_self_left,
Nat.mul_comm _ (n * (b / n)), Nat.mul_assoc, add_mul_mod_self_left]
@@ -676,9 +605,6 @@ theorem add_mod (a b n : Nat) : (a + b) % n = ((a % n) + (b % n)) % n := by
| zero => simp_all
| succ k => omega
@[simp] theorem mod_mul_mod {a b c : Nat} : (a % c * b) % c = a * b % c := by
rw [mul_mod, mod_mod, mul_mod]
/-! ### pow -/
theorem pow_succ' {m n : Nat} : m ^ n.succ = m * m ^ n := by
@@ -841,16 +767,6 @@ protected theorem two_pow_pred_mod_two_pow (h : 0 < w) :
rw [mod_eq_of_lt]
apply Nat.pow_pred_lt_pow (by omega) h
protected theorem pow_lt_pow_iff_pow_mul_le_pow {a n m : Nat} (h : 1 < a) :
a ^ n < a ^ m a ^ n * a a ^ m := by
rw [Nat.pow_add_one, Nat.pow_le_pow_iff_right (by omega), Nat.pow_lt_pow_iff_right (by omega)]
omega
@[simp]
theorem two_pow_pred_mul_two (h : 0 < w) :
2 ^ (w - 1) * 2 = 2 ^ w := by
simp [ Nat.pow_succ, Nat.sub_add_cancel h]
/-! ### log2 -/
@[simp]
@@ -873,10 +789,6 @@ theorem le_log2 (h : n ≠ 0) : k ≤ n.log2 ↔ 2 ^ k ≤ n := by
theorem log2_lt (h : n 0) : n.log2 < k n < 2 ^ k := by
rw [ Nat.not_le, Nat.not_le, le_log2 h]
@[simp]
theorem log2_two_pow : (2 ^ n).log2 = n := by
apply Nat.eq_of_le_of_lt_succ <;> simp [le_log2, log2_lt, NeZero.ne, Nat.pow_lt_pow_iff_right]
theorem log2_self_le (h : n 0) : 2 ^ n.log2 n := (le_log2 h).1 (Nat.le_refl _)
theorem lt_log2_self : n < 2 ^ (n.log2 + 1) :=
@@ -949,15 +861,15 @@ theorem shiftLeft_succ_inside (m n : Nat) : m <<< (n+1) = (2*m) <<< n := rfl
/-- Shiftleft on successor with multiple moved to outside. -/
theorem shiftLeft_succ : (m n), m <<< (n + 1) = 2 * (m <<< n)
| _, 0 => rfl
| _, k + 1 => by
| m, 0 => rfl
| m, k + 1 => by
rw [shiftLeft_succ_inside _ (k+1)]
rw [shiftLeft_succ _ k, shiftLeft_succ_inside]
/-- Shiftright on successor with division moved inside. -/
theorem shiftRight_succ_inside : m n, m >>> (n+1) = (m/2) >>> n
| _, 0 => rfl
| _, k + 1 => by
| m, 0 => rfl
| m, k + 1 => by
rw [shiftRight_succ _ (k+1)]
rw [shiftRight_succ_inside _ k, shiftRight_succ]

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@@ -8,6 +8,8 @@ import Init.Data.Nat.Linear
namespace Nat
protected theorem two_pow_pos (w : Nat) : 0 < 2^w := Nat.pos_pow_of_pos _ (by decide)
theorem nextPowerOfTwo_dec {n power : Nat} (h₁ : power > 0) (h₂ : power < n) : n - power * 2 < n - power := by
have : power * 2 = power + power := by simp_arith
rw [this, Nat.sub_add_eq]

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@@ -35,4 +35,4 @@ theorem neZero_iff {n : R} : NeZero n ↔ n ≠ 0 :=
fun h h.out, NeZero.mk
@[simp] theorem neZero_zero_iff_false {α : Type _} [Zero α] : NeZero (0 : α) False :=
fun _ NeZero.ne (0 : α) rfl, fun h h.elim
fun h h.ne rfl, fun h h.elim

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@@ -10,10 +10,8 @@ import Init.Data.Nat.Log2
/-- For decimal and scientific numbers (e.g., `1.23`, `3.12e10`).
Examples:
- `1.23` is syntax for `OfScientific.ofScientific (nat_lit 123) true (nat_lit 2)`
- `121e100` is syntax for `OfScientific.ofScientific (nat_lit 121) false (nat_lit 100)`
Note the use of `nat_lit`; there is no wrapping `OfNat.ofNat` in the resulting term.
- `OfScientific.ofScientific 123 true 2` represents `1.23`
- `OfScientific.ofScientific 121 false 100` represents `121e100`
-/
class OfScientific (α : Type u) where
ofScientific (mantissa : Nat) (exponentSign : Bool) (decimalExponent : Nat) : α

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@@ -8,5 +8,3 @@ import Init.Data.Option.Basic
import Init.Data.Option.BasicAux
import Init.Data.Option.Instances
import Init.Data.Option.Lemmas
import Init.Data.Option.Attach
import Init.Data.Option.List

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@@ -1,242 +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.Basic
import Init.Data.Option.List
import Init.Data.List.Attach
import Init.BinderPredicates
namespace Option
/--
Unsafe implementation of `attachWith`, taking advantage of the fact that the representation of
`Option {x // P x}` is the same as the input `Option α`.
-/
@[inline] private unsafe def attachWithImpl
(o : Option α) (P : α Prop) (_ : x o, P x) : Option {x // P x} := unsafeCast o
/-- "Attach" a proof `P x` that holds for the element of `o`, if present,
to produce a new option with the same element but in the type `{x // P x}`. -/
@[implemented_by attachWithImpl] def attachWith
(xs : Option α) (P : α Prop) (H : x xs, P x) : Option {x // P x} :=
match xs with
| none => none
| some x => some x, H x (mem_some_self x)
/-- "Attach" the proof that the element of `xs`, if present, is in `xs`
to produce a new option with the same elements but in the type `{x // x ∈ xs}`. -/
@[inline] def attach (xs : Option α) : Option {x // x xs} := xs.attachWith _ fun _ => id
@[simp] theorem attach_none : (none : Option α).attach = none := rfl
@[simp] theorem attachWith_none : (none : Option α).attachWith P H = none := rfl
@[simp] theorem attach_some {x : α} :
(some x).attach = some x, rfl := rfl
@[simp] theorem attachWith_some {x : α} {P : α Prop} (h : (b : α), b some x P b) :
(some x).attachWith P h = some x, by simpa using h := rfl
theorem attach_congr {o₁ o₂ : Option α} (h : o₁ = o₂) :
o₁.attach = o₂.attach.map (fun x => x.1, h x.2) := by
subst h
simp
theorem attachWith_congr {o₁ o₂ : Option α} (w : o₁ = o₂) {P : α Prop} {H : x o₁, P x} :
o₁.attachWith P H = o₂.attachWith P fun _ h => H _ (w h) := by
subst w
simp
theorem attach_map_coe (o : Option α) (f : α β) :
(o.attach.map fun (i : {i // i o}) => f i) = o.map f := by
cases o <;> simp
theorem attach_map_val (o : Option α) (f : α β) :
(o.attach.map fun i => f i.val) = o.map f :=
attach_map_coe _ _
@[simp]
theorem attach_map_subtype_val (o : Option α) :
o.attach.map Subtype.val = o :=
(attach_map_coe _ _).trans (congrFun Option.map_id _)
theorem attachWith_map_coe {p : α Prop} (f : α β) (o : Option α) (H : a o, p a) :
((o.attachWith p H).map fun (i : { i // p i}) => f i.val) = o.map f := by
cases o <;> simp [H]
theorem attachWith_map_val {p : α Prop} (f : α β) (o : Option α) (H : a o, p a) :
((o.attachWith p H).map fun i => f i.val) = o.map f :=
attachWith_map_coe _ _ _
@[simp]
theorem attachWith_map_subtype_val {p : α Prop} (o : Option α) (H : a o, p a) :
(o.attachWith p H).map Subtype.val = o :=
(attachWith_map_coe _ _ _).trans (congrFun Option.map_id _)
@[simp] theorem mem_attach : (o : Option α) (x : {x // x o}), x o.attach
| none, x, h => by simp at h
| some a, x, h => by simpa using h
@[simp] theorem isNone_attach (o : Option α) : o.attach.isNone = o.isNone := by
cases o <;> simp
@[simp] theorem isNone_attachWith {p : α Prop} (o : Option α) (H : a o, p a) :
(o.attachWith p H).isNone = o.isNone := by
cases o <;> simp
@[simp] theorem isSome_attach (o : Option α) : o.attach.isSome = o.isSome := by
cases o <;> simp
@[simp] theorem isSome_attachWith {p : α Prop} (o : Option α) (H : a o, p a) :
(o.attachWith p H).isSome = o.isSome := by
cases o <;> simp
@[simp] theorem attach_eq_none_iff (o : Option α) : o.attach = none o = none := by
cases o <;> simp
@[simp] theorem attach_eq_some_iff {o : Option α} {x : {x // x o}} :
o.attach = some x o = some x.val := by
cases o <;> cases x <;> simp
@[simp] theorem attachWith_eq_none_iff {p : α Prop} (o : Option α) (H : a o, p a) :
o.attachWith p H = none o = none := by
cases o <;> simp
@[simp] theorem attachWith_eq_some_iff {p : α Prop} {o : Option α} (H : a o, p a) {x : {x // p x}} :
o.attachWith p H = some x o = some x.val := by
cases o <;> cases x <;> simp
@[simp] theorem get_attach {o : Option α} (h : o.attach.isSome = true) :
o.attach.get h = o.get (by simpa using h), by simp := by
cases o
· simp at h
· simp [get_some]
@[simp] theorem get_attachWith {p : α Prop} {o : Option α} (H : a o, p a) (h : (o.attachWith p H).isSome) :
(o.attachWith p H).get h = o.get (by simpa using h), H _ (by simp) := by
cases o
· simp at h
· simp [get_some]
@[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
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
theorem attachWith_map {o : Option α} (f : α β) {P : β Prop} {H : (b : β), b o.map f P b} :
(o.map f).attachWith P H = (o.attachWith (P f) (fun _ h => H _ (mem_map_of_mem f h))).map
fun x, h => f x, h := by
cases o <;> simp
theorem map_attach {o : Option α} (f : { x // x o } β) :
o.attach.map f = o.pmap (fun a (h : a o) => f a, h) (fun _ h => h) := by
cases o <;> simp
theorem map_attachWith {o : Option α} {P : α Prop} {H : (a : α), a o P a}
(f : { x // P x } β) :
(o.attachWith P H).map f =
o.pmap (fun a (h : a o P a) => f a, h.2) (fun a h => h, H a h) := by
cases o <;> simp
theorem attach_bind {o : Option α} {f : α Option β} :
(o.bind f).attach =
o.attach.bind fun x, h => (f x).attach.map fun y, h' => y, mem_bind_iff.mpr x, h, h' := by
cases o <;> simp
theorem bind_attach {o : Option α} {f : {x // x o} Option β} :
o.attach.bind f = o.pbind fun a h => f a, h := by
cases o <;> simp
theorem pbind_eq_bind_attach {o : Option α} {f : (a : α) a o Option β} :
o.pbind f = o.attach.bind fun x, h => f x h := by
cases o <;> simp
theorem attach_filter {o : Option α} {p : α Bool} :
(o.filter p).attach =
o.attach.bind fun x, h => if h' : p x then some x, by simp_all else none := by
cases o with
| none => simp
| some a =>
simp only [filter_some, attach_some]
ext
simp only [mem_def, attach_eq_some_iff, ite_none_right_eq_some, some.injEq, some_bind,
dite_none_right_eq_some]
constructor
· rintro h, w
refine h, by ext; simpa using w
· rintro h, rfl
simp [h]
theorem filter_attach {o : Option α} {p : {x // x o} Bool} :
o.attach.filter p = o.pbind fun a h => if p a, h then some a, h else none := by
cases o <;> simp [filter_some]
/-! ## unattach
`Option.unattach` is the (one-sided) inverse of `Option.attach`. It is a synonym for `Option.map Subtype.val`.
We use it by providing a simp lemma `l.attach.unattach = l`, and simp lemmas which recognize higher order
functions applied to `l : Option { x // p x }` which only depend on the value, not the predicate, and rewrite these
in terms of a simpler function applied to `l.unattach`.
Further, we provide simp lemmas that push `unattach` inwards.
-/
/--
A synonym for `l.map (·.val)`. Mostly this should not be needed by users.
It is introduced as an intermediate step by lemmas such as `map_subtype`,
and is ideally subsequently simplified away by `unattach_attach`.
If not, usually the right approach is `simp [Option.unattach, -Option.map_subtype]` to unfold.
-/
def unattach {α : Type _} {p : α Prop} (o : Option { x // p x }) := o.map (·.val)
@[simp] theorem unattach_none {p : α Prop} : (none : Option { x // p x }).unattach = none := rfl
@[simp] theorem unattach_some {p : α Prop} {a : { x // p x }} :
(some a).unattach = a.val := rfl
@[simp] theorem isSome_unattach {p : α Prop} {o : Option { x // p x }} :
o.unattach.isSome = o.isSome := by
simp [unattach]
@[simp] theorem isNone_unattach {p : α Prop} {o : Option { x // p x }} :
o.unattach.isNone = o.isNone := by
simp [unattach]
@[simp] theorem unattach_attach (o : Option α) : o.attach.unattach = o := by
cases o <;> simp
@[simp] theorem unattach_attachWith {p : α Prop} {o : Option α}
{H : a o, p a} :
(o.attachWith p H).unattach = o := by
cases o <;> simp
/-! ### Recognizing higher order functions on subtypes using a function that only depends on the value. -/
/--
This lemma identifies maps over lists of subtypes, where the function only depends on the value, not the proposition,
and simplifies these to the function directly taking the value.
-/
@[simp] theorem map_subtype {p : α Prop} {o : Option { x // p x }}
{f : { x // p x } β} {g : α β} {hf : x h, f x, h = g x} :
o.map f = o.unattach.map g := by
cases o <;> simp [hf]
@[simp] theorem bind_subtype {p : α Prop} {o : Option { x // p x }}
{f : { x // p x } Option β} {g : α Option β} {hf : x h, f x, h = g x} :
(o.bind f) = o.unattach.bind g := by
cases o <;> simp [hf]
@[simp] theorem unattach_filter {p : α Prop} {o : Option { x // p x }}
{f : { x // p x } Bool} {g : α Bool} {hf : x h, f x, h = g x} :
(o.filter f).unattach = o.unattach.filter g := by
cases o
· simp
· simp only [filter_some, hf, unattach_some]
split <;> simp
end Option

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@@ -4,7 +4,9 @@ Released under Apache 2.0 license as described in the file LICENSE.
Authors: Leonardo de Moura, Mario Carneiro
-/
prelude
import Init.Core
import Init.Control.Basic
import Init.Coe
namespace Option
@@ -200,7 +202,7 @@ result.
instance (α) [BEq α] [LawfulBEq α] : LawfulBEq (Option α) where
rfl {x} :=
match x with
| some _ => LawfulBEq.rfl (α := α)
| some x => LawfulBEq.rfl (α := α)
| none => rfl
eq_of_beq {x y h} := by
match x, y with

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

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@@ -79,7 +79,7 @@ theorem eq_none_iff_forall_not_mem : o = none ↔ ∀ a, a ∉ o :=
theorem isSome_iff_exists : isSome x a, x = some a := by cases x <;> simp [isSome]
theorem isSome_eq_isSome : (isSome x = isSome y) (x = none y = none) := by
@[simp] theorem isSome_eq_isSome : (isSome x = isSome y) (x = none y = none) := by
cases x <;> cases y <;> simp
@[simp] theorem isNone_none : @isNone α none = true := rfl
@@ -138,10 +138,6 @@ theorem bind_eq_none' {o : Option α} {f : α → Option β} :
o.bind f = none b a, a o b f a := by
simp only [eq_none_iff_forall_not_mem, not_exists, not_and, mem_def, bind_eq_some]
theorem mem_bind_iff {o : Option α} {f : α Option β} :
b o.bind f a, a o b f a := by
cases o <;> simp
theorem bind_comm {f : α β Option γ} (a : Option α) (b : Option β) :
(a.bind fun x => b.bind (f x)) = b.bind fun y => a.bind fun x => f x y := by
cases a <;> cases b <;> rfl
@@ -236,27 +232,9 @@ theorem isSome_filter_of_isSome (p : α → Bool) (o : Option α) (h : (o.filter
cases o <;> simp at h
@[simp] theorem filter_eq_none {p : α Bool} :
o.filter p = none o = none a, a o ¬ p a := by
Option.filter p o = none o = none a, a o ¬ p a := by
cases o <;> simp [filter_some]
@[simp] theorem filter_eq_some {o : Option α} {p : α Bool} :
o.filter p = some a a o p a := by
cases o with
| none => simp
| some a =>
simp [filter_some]
split <;> rename_i h
· simp only [some.injEq, iff_self_and]
rintro rfl
exact h
· simp only [reduceCtorEq, false_iff, not_and, Bool.not_eq_true]
rintro rfl
simpa using h
theorem mem_filter_iff {p : α Bool} {a : α} {o : Option α} :
a o.filter p a o p a := by
simp
@[simp] theorem all_guard (p : α Prop) [DecidablePred p] (a : α) :
Option.all q (guard p a) = (!p a || q a) := by
simp only [guard]
@@ -330,8 +308,8 @@ theorem guard_comp {p : α → Prop} [DecidablePred p] {f : β → α} :
theorem liftOrGet_eq_or_eq {f : α α α} (h : a b, f a b = a f a b = b) :
o₁ o₂, liftOrGet f o₁ o₂ = o₁ liftOrGet f o₁ o₂ = o₂
| none, none => .inl rfl
| some _, none => .inl rfl
| none, some _ => .inr rfl
| some a, none => .inl rfl
| none, some b => .inr rfl
| some a, some b => by have := h a b; simp [liftOrGet] at this ; exact this
@[simp] theorem liftOrGet_none_left {f} {b : Option α} : liftOrGet f none b = b := by
@@ -372,17 +350,9 @@ end choice
@[simp] theorem toList_none (α : Type _) : (none : Option α).toList = [] := rfl
-- See `Init.Data.Option.List` for lemmas about `toList`.
@[simp] theorem some_or : (some a).or o = some a := rfl
@[simp] theorem or_some : (some a).or o = some a := rfl
@[simp] theorem none_or : none.or o = o := rfl
@[deprecated some_or (since := "2024-11-03")] theorem or_some : (some a).or o = some a := rfl
/-- This will be renamed to `or_some` once the existing deprecated lemma is removed. -/
@[simp] theorem or_some' {o : Option α} : o.or (some a) = o.getD a := by
cases o <;> rfl
theorem or_eq_bif : or o o' = bif o.isSome then o else o' := by
cases o <;> rfl

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@@ -1,38 +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.Lemmas
namespace Option
@[simp] theorem mem_toList {a : α} {o : Option α} : a o.toList a o := by
cases o <;> simp [eq_comm]
@[simp] theorem forIn'_none [Monad m] (b : β) (f : (a : α) a none β m (ForInStep β)) :
forIn' none b f = pure b := by
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] (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
cases o <;> rfl
@[simp] theorem forIn_toList [Monad m] (o : Option α) (b : β) (f : α β m (ForInStep β)) :
forIn o.toList b f = forIn o b f := by
cases o <;> rfl
end Option

View File

@@ -7,8 +7,6 @@ prelude
import Init.SimpLemmas
import Init.NotationExtra
namespace Prod
instance [BEq α] [BEq β] [LawfulBEq α] [LawfulBEq β] : LawfulBEq (α × β) where
eq_of_beq {a b} (h : a.1 == b.1 && a.2 == b.2) := by
cases a; cases b
@@ -16,65 +14,9 @@ instance [BEq α] [BEq β] [LawfulBEq α] [LawfulBEq β] : LawfulBEq (α × β)
rfl {a} := by cases a; simp [BEq.beq, LawfulBEq.rfl]
@[simp]
protected theorem «forall» {p : α × β Prop} : ( x, p x) a b, p (a, b) :=
protected theorem Prod.forall {p : α × β Prop} : ( x, p x) a b, p (a, b) :=
fun h a b h (a, b), fun h a, b h a b
@[simp]
protected theorem «exists» {p : α × β Prop} : ( x, p x) a b, p (a, b) :=
protected theorem Prod.exists {p : α × β Prop} : ( x, p x) a b, p (a, b) :=
fun a, b, h a, b, h, fun a, b, h a, b, h
@[simp] theorem map_id : Prod.map (@id α) (@id β) = id := rfl
@[simp] theorem map_id' : Prod.map (fun a : α => a) (fun b : β => b) = fun x x := rfl
/--
Composing a `Prod.map` with another `Prod.map` is equal to
a single `Prod.map` of composed functions.
-/
theorem map_comp_map (f : α β) (f' : γ δ) (g : β ε) (g' : δ ζ) :
Prod.map g g' Prod.map f f' = Prod.map (g f) (g' f') :=
rfl
/--
Composing a `Prod.map` with another `Prod.map` is equal to
a single `Prod.map` of composed functions, fully applied.
-/
theorem map_map (f : α β) (f' : γ δ) (g : β ε) (g' : δ ζ) (x : α × γ) :
Prod.map g g' (Prod.map f f' x) = Prod.map (g f) (g' f') x :=
rfl
/-- Swap the factors of a product. `swap (a, b) = (b, a)` -/
def swap : α × β β × α := fun p => (p.2, p.1)
@[simp]
theorem swap_swap : x : α × β, swap (swap x) = x
| _, _ => rfl
@[simp]
theorem fst_swap {p : α × β} : (swap p).1 = p.2 :=
rfl
@[simp]
theorem snd_swap {p : α × β} : (swap p).2 = p.1 :=
rfl
@[simp]
theorem swap_prod_mk {a : α} {b : β} : swap (a, b) = (b, a) :=
rfl
@[simp]
theorem swap_swap_eq : swap swap = @id (α × β) :=
funext swap_swap
@[simp]
theorem swap_inj {p q : α × β} : swap p = swap q p = q := by
cases p; cases q; simp [and_comm]
/--
For two functions `f` and `g`, the composition of `Prod.map f g` with `Prod.swap`
is equal to the composition of `Prod.swap` with `Prod.map g f`.
-/
theorem map_comp_swap (f : α β) (g : γ δ) :
Prod.map f g Prod.swap = Prod.swap Prod.map g f := rfl
end Prod

View File

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

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