slightly unhappy change to test

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.

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src/Init.lean

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

src/Init/Data/Array/Basic.lean

@@ -80,26 +80,6 @@ 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
-
-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
@@ -418,25 +398,20 @@ 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
@@ -542,13 +517,8 @@ 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)]`. -/

src/Init/Data/Array/Bootstrap.lean

@@ -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

src/Init/Data/Array/DecidableEq.lean

@@ -6,8 +6,6 @@ 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
@@ -28,14 +26,6 @@ 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) :
     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]
@@ -43,29 +33,6 @@ theorem rel_of_isEqv (r : α → α → Bool) (a b : Array α) :
   · 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 r a b, fun ⟨h, w⟩ => by
-    simp only [isEqv, ← h, ↓reduceDIte]
-    exact isEqvAux_of_rel r a b h a.size (by simp [h]) w⟩
-
-theorem isEqv_eq_decide (a b : Array α) (r) :
-    Array.isEqv a b r =
-      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 (fun x y => x = y) a b h
   exact ext _ _ h (fun i lt _ => by simpa using h' i lt)
@@ -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

src/Init/Data/Array/GetLit.lean

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

src/Init/Data/Array/Lemmas.lean

@@ -9,7 +9,6 @@ import Init.Data.List.Impl
 import Init.Data.List.Monadic
 import Init.Data.List.Range
 import Init.Data.List.Nat.TakeDrop
-import Init.Data.List.Nat.Modify
 import Init.Data.Array.Mem
 import Init.TacticsExtra
 
@@ -19,6 +18,8 @@ import Init.TacticsExtra
 
 namespace Array
 
+@[simp] theorem getElem_toList {a : Array α} {i : Nat} (h : i < a.size) : a.toList[i] = a[i] := rfl
+
 @[simp] theorem getElem_mk {xs : List α} {i : Nat} (h : i < xs.length) : (Array.mk xs)[i] = xs[i] := rfl
 
 theorem getElem_eq_getElem_toList {a : Array α} (h : i < a.size) : a[i] = a.toList[i] := by
@@ -85,6 +86,16 @@ We prefer to pull `List.toArray` outwards.
     (a.toArrayAux b).size = b.size + a.length := by
   simp [size]
 
+@[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
+
 @[simp] theorem push_toArray (l : List α) (a : α) : l.toArray.push a = (l ++ [a]).toArray := by
   apply ext'
   simp
@@ -159,9 +170,6 @@ namespace Array
 
 @[simp] theorem singleton_def (v : α) : singleton v = #[v] := rfl
 
--- This is a duplicate of `List.toArray_toList`.
--- It's confusing to guess which namespace this theorem should live in,
--- so we provide both.
 @[simp] theorem toArray_toList (a : Array α) : a.toList.toArray = a := rfl
 
 @[simp] theorem length_toList {l : Array α} : l.toList.length = l.size := rfl
@@ -852,12 +860,6 @@ theorem getElem_modify {as : Array α} {x i} (h : i < (as.modify x f).size) :
   · simp only [Id.bind_eq, get_set _ _ _ (by simpa using h)]; split <;> simp [*]
   · rw [if_neg (mt (by rintro rfl; exact h) (by simp_all))]
 
-@[simp] theorem toList_modify (as : Array α) (f : α → α) :
-    (as.modify x f).toList = as.toList.modify f x := by
-  apply List.ext_getElem
-  · simp
-  · simp [getElem_modify, List.getElem_modify]
-
 theorem getElem_modify_self {as : Array α} {i : Nat} (f : α → α) (h : i < (as.modify i f).size) :
     (as.modify i f)[i] = f (as[i]'(by simpa using h)) := by
   simp [getElem_modify h]
@@ -1440,11 +1442,6 @@ theorem all_toArray (p : α → Bool) (l : List α) : l.toArray.all p = l.all p
   apply ext'
   simp
 
-@[simp] theorem modify_toArray (f : α → α) (l : List α) :
-    l.toArray.modify i f = (l.modify f i).toArray := by
-  apply ext'
-  simp
-
 @[simp] theorem filter_toArray' (p : α → Bool) (l : List α) (h : stop = l.toArray.size) :
     l.toArray.filter p 0 stop = (l.filter p).toArray := by
   subst h

src/Init/Data/Array/MapIdx.lean

@@ -9,19 +9,20 @@ import Init.Data.List.MapIdx
 
 namespace Array
 
-/-! ### mapFinIdx -/
+
+/-! ### mapIdx -/
 
 -- This could also be proved from `SatisfiesM_mapIdxM` in Batteries.
-theorem mapFinIdx_induction (as : Array α) (f : Fin as.size → α → β)
+theorem mapIdx_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
+    motive as.size ∧ ∃ eq : (Array.mapIdx as f).size = as.size,
+      ∀ i h, p ⟨i, h⟩ ((Array.mapIdx 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
+    let arr : Array β := Array.mapIdxM.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]
+    induction i generalizing j bs with simp [mapIdxM.map]
     | zero =>
       have := (Nat.zero_add _).symm.trans h
       exact ⟨this ▸ hm, h₁ ▸ this, fun _ _ => h₂ ..⟩
@@ -35,58 +36,29 @@ theorem mapFinIdx_induction (as : Array α) (f : Fin as.size → α → β)
           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
+  simp [mapIdx, mapIdxM]; 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
-
-/-! ### 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)
+theorem mapIdx_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.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 :=
+@[simp] theorem size_mapIdx (a : Array α) (f : Fin a.size → 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 size_zipWithIndex (as : Array α) : as.zipWithIndex.size = as.size :=
+  Array.size_mapIdx _ _
 
-@[simp] theorem getElem?_mapIdx (a : Array α) (f : Nat → α → β) (i : Nat) :
+@[simp] theorem getElem_mapIdx (a : Array α) (f : Fin a.size → α → β) (i : Nat)
+    (h : i < (mapIdx a f).size) :
+    (a.mapIdx f)[i] = f ⟨i, by simp_all⟩ (a[i]'(by simp_all)) :=
+  (mapIdx_spec _ _ (fun i b => b = f i a[i]) fun _ => rfl).2 i _
+
+@[simp] theorem getElem?_mapIdx (a : Array α) (f : Fin a.size → α → β) (i : Nat) :
     (a.mapIdx f)[i]? =
-      a[i]?.map (f i) := by
-  simp [getElem?_def, size_mapIdx, getElem_mapIdx]
+      a[i]?.pbind fun b h => f ⟨i, (getElem?_eq_some_iff.1 h).1⟩ b := by
+  simp only [getElem?_def, size_mapIdx, getElem_mapIdx]
+  split <;> simp_all
 
 end Array

src/Init/Data/BitVec/Lemmas.lean

@@ -316,12 +316,6 @@ theorem getLsbD_ofNat (n : Nat) (x : Nat) (i : Nat) :
   simp [Nat.sub_sub_eq_min, Nat.min_eq_right]
   omega
 
-@[simp] theorem sub_add_bmod_cancel {x y : BitVec w} :
-    ((((2 ^ w : Nat) - y.toNat) : Int) + x.toNat).bmod (2 ^ w) =
-      ((x.toNat : Int) - y.toNat).bmod (2 ^ w) := by
-  rw [Int.sub_eq_add_neg, Int.add_assoc, Int.add_comm, Int.bmod_add_cancel, Int.add_comm,
-    Int.sub_eq_add_neg]
-
 private theorem lt_two_pow_of_le {x m n : Nat} (lt : x < 2 ^ m) (le : m ≤ n) : x < 2 ^ n :=
   Nat.lt_of_lt_of_le lt (Nat.pow_le_pow_of_le_right (by trivial : 0 < 2) le)
 
@@ -1980,10 +1974,6 @@ theorem sub_def {n} (x y : BitVec n) : x - y = .ofNat n ((2^n - y.toNat) + x.toN
 @[simp] theorem toNat_sub {n} (x y : BitVec n) :
     (x - y).toNat = (((2^n - y.toNat) + x.toNat) % 2^n) := rfl
 
-@[simp, bv_toNat] theorem toInt_sub {x y : BitVec w} :
-    (x - y).toInt = (x.toInt - y.toInt).bmod (2 ^ w) := by
-  simp [toInt_eq_toNat_bmod, @Int.ofNat_sub y.toNat (2 ^ w) (by omega)]
-
 -- We prefer this lemma to `toNat_sub` for the `bv_toNat` simp set.
 -- For reasons we don't yet understand, unfolding via `toNat_sub` sometimes
 -- results in `omega` generating proof terms that are very slow in the kernel.
@@ -2006,8 +1996,6 @@ theorem ofNat_sub_ofNat {n} (x y : Nat) : BitVec.ofNat n x - BitVec.ofNat n y =
 
 @[simp] protected theorem sub_zero (x : BitVec n) : x - 0#n = x := by apply eq_of_toNat_eq ; simp
 
-@[simp] protected theorem zero_sub (x : BitVec n) : 0#n - x = -x := rfl
-
 @[simp] protected theorem sub_self (x : BitVec n) : x - x = 0#n := by
   apply eq_of_toNat_eq
   simp only [toNat_sub]
@@ -2020,8 +2008,18 @@ theorem ofNat_sub_ofNat {n} (x y : Nat) : BitVec.ofNat n x - BitVec.ofNat n y =
 
 theorem toInt_neg {x : BitVec w} :
     (-x).toInt = (-x.toInt).bmod (2 ^ w) := by
-  rw [← BitVec.zero_sub, toInt_sub]
-  simp [BitVec.toInt_ofNat]
+  simp only [toInt_eq_toNat_bmod, toNat_neg, Int.ofNat_emod, Int.emod_bmod_congr]
+  rw [← Int.subNatNat_of_le (by omega), Int.subNatNat_eq_coe, Int.sub_eq_add_neg, Int.add_comm,
+    Int.bmod_add_cancel]
+  by_cases h : x.toNat < ((2 ^ w) + 1) / 2
+  · rw [Int.bmod_pos (x := x.toNat)]
+    all_goals simp only [toNat_mod_cancel']
+    norm_cast
+  · rw [Int.bmod_neg (x := x.toNat)]
+    · simp only [toNat_mod_cancel']
+      rw_mod_cast [Int.neg_sub, Int.sub_eq_add_neg, Int.add_comm, Int.bmod_add_cancel]
+    · norm_cast
+      simp_all
 
 @[simp] theorem toFin_neg (x : BitVec n) :
     (-x).toFin = Fin.ofNat' (2^n) (2^n - x.toNat) :=

src/Init/Data/Int/DivModLemmas.lean

@@ -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]

src/Init/Data/List/Basic.lean

@@ -38,7 +38,7 @@ The operations are organized as follow:
 * 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`.
@@ -122,11 +122,6 @@ 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
@@ -1119,35 +1114,6 @@ 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 -/
 
 /--

src/Init/Data/List/Impl.lean

@@ -38,7 +38,7 @@ The following operations were already given `@[csimp]` replacements in `Init/Dat
 
 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`.
 
 -/
@@ -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`. -/

src/Init/Data/List/Nat.lean

@@ -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

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

@@ -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

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

@@ -1,102 +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
-
-namespace List
-
-/-! ### 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]
-
-/-! ### 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 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 _ _)
-
-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) <$> l[m]?
-  | n, l, 0 => by cases l <;> cases n <;> simp
-  | n, [], _+1 => by cases n <;> rfl
-  | 0, _ :: l, m+1 => by cases h : l[m]? <;> simp [h, modify, m.succ_ne_zero.symm]
-  | n+1, a :: l, m+1 => by
-    simp only [modify_succ_cons, getElem?_cons_succ, Nat.reduceEqDiff, Option.map_eq_map]
-    refine (getElem?_modify f n l m).trans ?_
-    cases h' : l[m]? <;> by_cases h : n = m <;>
-      simp [h, if_pos, if_neg, Option.map, mt Nat.succ.inj, not_false_iff, h']
-
-@[simp] theorem length_modifyTailIdx (f : List α → List α) (H : ∀ l, length (f l) = length l) :
-    ∀ n l, length (modifyTailIdx f n l) = length l
-  | 0, _ => H _
-  | _+1, [] => rfl
-  | _+1, _ :: _ => congrArg (·+1) (length_modifyTailIdx _ H _ _)
-
-theorem modifyTailIdx_add (f : List α → List α) (n) (l₁ l₂ : List α) :
-    modifyTailIdx f (l₁.length + n) (l₁ ++ l₂) = l₁ ++ modifyTailIdx f n l₂ := by
-  induction l₁ <;> simp [*, Nat.succ_add]
-
-@[simp] theorem length_modify (f : α → α) : ∀ n l, length (modify f n l) = length l :=
-  length_modifyTailIdx _ fun l => by cases l <;> rfl
-
-@[simp] theorem getElem?_modify_eq (f : α → α) (n) (l : List α) :
-    (modify f n l)[n]? = f <$> 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]
-
-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 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} (h : n < length l) :
-    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_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) ..⟩
-
-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)
-
-end List

src/Init/Data/Nat/Lemmas.lean

@@ -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

src/Init/NotationExtra.lean

@@ -10,7 +10,6 @@ import Init.Data.ToString.Basic
 import Init.Data.Array.Subarray
 import Init.Conv
 import Init.Meta
-import Init.While
 
 namespace Lean
 
@@ -345,6 +344,42 @@ syntax (name := solveTactic) "solve" withPosition((ppDedent(ppLine) colGe "| " t
 macro_rules
   | `(tactic| solve $[| $ts]* ) => `(tactic| focus first $[| ($ts); done]*)
 
+/-! # `repeat` and `while` notation -/
+
+inductive Loop where
+  | mk
+
+@[inline]
+partial def Loop.forIn {β : Type u} {m : Type u → Type v} [Monad m] (_ : Loop) (init : β) (f : Unit → β → m (ForInStep β)) : m β :=
+  let rec @[specialize] loop (b : β) : m β := do
+    match ← f () b with
+      | ForInStep.done b  => pure b
+      | ForInStep.yield b => loop b
+  loop init
+
+instance : ForIn m Loop Unit where
+  forIn := Loop.forIn
+
+syntax "repeat " doSeq : doElem
+
+macro_rules
+  | `(doElem| repeat $seq) => `(doElem| for _ in Loop.mk do $seq)
+
+syntax "while " ident " : " termBeforeDo " do " doSeq : doElem
+
+macro_rules
+  | `(doElem| while $h : $cond do $seq) => `(doElem| repeat if $h : $cond then $seq else break)
+
+syntax "while " termBeforeDo " do " doSeq : doElem
+
+macro_rules
+  | `(doElem| while $cond do $seq) => `(doElem| repeat if $cond then $seq else break)
+
+syntax "repeat " doSeq ppDedent(ppLine) "until " term : doElem
+
+macro_rules
+  | `(doElem| repeat $seq until $cond) => `(doElem| repeat do $seq:doSeq; if $cond then break)
+
 macro:50 e:term:51 " matches " p:sepBy1(term:51, " | ") : term =>
   `(((match $e:term with | $[$p:term]|* => true | _ => false) : Bool))
 

src/Init/While.lean

@@ -1,51 +0,0 @@
-/-
-Copyright (c) 2020 Microsoft Corporation. All rights reserved.
-Released under Apache 2.0 license as described in the file LICENSE.
-Authors: Leonardo de Moura
--/
-prelude
-import Init.Core
-
-/-!
-# Notation for `while` and `repeat` loops.
--/
-
-namespace Lean
-
-/-! # `repeat` and `while` notation -/
-
-inductive Loop where
-  | mk
-
-@[inline]
-partial def Loop.forIn {β : Type u} {m : Type u → Type v} [Monad m] (_ : Loop) (init : β) (f : Unit → β → m (ForInStep β)) : m β :=
-  let rec @[specialize] loop (b : β) : m β := do
-    match ← f () b with
-      | ForInStep.done b  => pure b
-      | ForInStep.yield b => loop b
-  loop init
-
-instance : ForIn m Loop Unit where
-  forIn := Loop.forIn
-
-syntax "repeat " doSeq : doElem
-
-macro_rules
-  | `(doElem| repeat $seq) => `(doElem| for _ in Loop.mk do $seq)
-
-syntax "while " ident " : " termBeforeDo " do " doSeq : doElem
-
-macro_rules
-  | `(doElem| while $h : $cond do $seq) => `(doElem| repeat if $h : $cond then $seq else break)
-
-syntax "while " termBeforeDo " do " doSeq : doElem
-
-macro_rules
-  | `(doElem| while $cond do $seq) => `(doElem| repeat if $cond then $seq else break)
-
-syntax "repeat " doSeq ppDedent(ppLine) "until " term : doElem
-
-macro_rules
-  | `(doElem| repeat $seq until $cond) => `(doElem| repeat do $seq:doSeq; if $cond then break)
-
-end Lean

src/Lean/Declaration.lean

@@ -369,13 +369,8 @@ def RecursorVal.getFirstIndexIdx (v : RecursorVal) : Nat :=
 def RecursorVal.getFirstMinorIdx (v : RecursorVal) : Nat :=
   v.numParams + v.numMotives
 
-/-- The inductive type of the major argument of the recursor. -/
-def RecursorVal.getMajorInduct (v : RecursorVal) : Name :=
-  go v.getMajorIdx v.type
-where
-  go
-  | 0, e => e.bindingDomain!.getAppFn.constName!
-  | n+1, e => go n e.bindingBody!
+def RecursorVal.getInduct (v : RecursorVal) : Name :=
+  v.name.getPrefix
 
 inductive QuotKind where
   | type  -- `Quot`

src/Lean/Elab/Syntax.lean

@@ -146,7 +146,7 @@ where
       let args ← args.mapM fun arg => withNestedParser do process arg
       mkParserSeq args
     else
-      let args ← args.mapIdxM fun i arg => withReader (fun ctx => { ctx with first := ctx.first && i == 0 }) do process arg
+      let args ← args.mapIdxM fun i arg => withReader (fun ctx => { ctx with first := ctx.first && i.val == 0 }) do process arg
       mkParserSeq args
 
   ensureNoPrec (stx : Syntax) :=

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

@@ -119,7 +119,7 @@ private def pre (pattern : AbstractMVarsResult) (state : IO.Ref PatternMatchStat
         let ids ← ids.mapIdxM fun i id =>
           match id.getNat with
           | 0 => throwErrorAt id "positive integer expected"
-          | n+1 => pure (n, i)
+          | n+1 => pure (n, i.1)
         let ids := ids.qsort (·.1 < ·.1)
         unless @Array.allDiff _ ⟨(·.1 == ·.1)⟩ ids do
           throwError "occurrence list is not distinct"

src/Lean/Meta/IndPredBelow.lean

@@ -54,7 +54,7 @@ def mkContext (declName : Name) : MetaM Context := do
   let typeInfos ← indVal.all.toArray.mapM getConstInfoInduct
   let motiveTypes ← typeInfos.mapM motiveType
   let motives ← motiveTypes.mapIdxM fun j motive =>
-    return (← motiveName motiveTypes j, motive)
+    return (← motiveName motiveTypes j.val, motive)
   let headers ← typeInfos.mapM $ mkHeader motives indVal.numParams
   return {
     motives := motives
@@ -214,7 +214,7 @@ def mkConstructor (ctx : Context) (i : Nat) (ctor : Name) : MetaM Constructor :=
 
 def mkInductiveType
     (ctx : Context)
-    (i : Nat)
+    (i : Fin ctx.typeInfos.size)
     (indVal : InductiveVal) : MetaM InductiveType := do
   return {
     name := ctx.belowNames[i]!
@@ -340,11 +340,11 @@ where
   mkIH
       (params : Array Expr)
       (motives : Array Expr)
-      (idx : Nat)
+      (idx : Fin ctx.motives.size)
       (motive : Name × Expr) : MetaM $ Name × (Array Expr → MetaM Expr) := do
     let name :=
       if ctx.motives.size > 1
-      then mkFreshUserName <| .mkSimple s!"ih_{idx + 1}"
+      then mkFreshUserName <| .mkSimple s!"ih_{idx.val.succ}"
       else mkFreshUserName <| .mkSimple "ih"
     let ih ← instantiateForall motive.2 params
     let mkDomain (_ : Array Expr) : MetaM Expr :=
@@ -353,7 +353,7 @@ where
         let args := params ++ motives ++ ys
         let premise :=
           mkAppN
-            (mkConst ctx.belowNames[idx]! levels) args
+            (mkConst ctx.belowNames[idx.val]! levels) args
         let conclusion :=
           mkAppN motives[idx]! ys
         mkForallFVars ys (←mkArrow premise conclusion)

src/Lean/Meta/Match/CaseArraySizes.lean

@@ -70,7 +70,7 @@ def caseArraySizes (mvarId : MVarId) (fvarId : FVarId) (sizes : Array Nat) (xNam
       let subst  := subgoal.subst
       let mvarId := subgoal.mvarId
       let hEqSz  := (subst.get hEq).fvarId!
-      if h : i < sizes.size then
+      if h : i.val < sizes.size then
          let n := sizes.get ⟨i, h⟩
          let mvarId ← mvarId.clear subgoal.newHs[0]!
          let mvarId ← mvarId.clear (subst.get aSizeFVarId).fvarId!

src/Lean/Meta/Match/Match.lean

@@ -545,7 +545,7 @@ private def processValue (p : Problem) : MetaM (Array Problem) := do
   let subgoals ← caseValues p.mvarId x.fvarId! values (substNewEqs := true)
   subgoals.mapIdxM fun i subgoal => do
     trace[Meta.Match.match] "processValue subgoal\n{MessageData.ofGoal subgoal.mvarId}"
-    if h : i < values.size then
+    if h : i.val < values.size then
       let value := values.get ⟨i, h⟩
       -- (x = value) branch
       let subst := subgoal.subst
@@ -599,7 +599,7 @@ private def processArrayLit (p : Problem) : MetaM (Array Problem) := do
   let sizes := collectArraySizes p
   let subgoals ← caseArraySizes p.mvarId x.fvarId! sizes
   subgoals.mapIdxM fun i subgoal => do
-    if i < sizes.size then
+    if i.val < sizes.size then
       let size     := sizes.get! i
       let subst    := subgoal.subst
       let elems    := subgoal.elems.toList

src/Lean/Meta/Tactic/FunInd.lean

@@ -643,7 +643,7 @@ def abstractIndependentMVars (mvars : Array MVarId) (index : Nat) (e : Expr) : M
       pure mvar
   trace[Meta.FunInd] "abstractIndependentMVars, reverted mvars: {mvars}"
   let decls := mvars.mapIdx fun i mvar =>
-    (.mkSimple s!"case{i+1}", (fun _ => mvar.getType))
+    (.mkSimple s!"case{i.val+1}", (fun _ => mvar.getType))
   Meta.withLocalDeclsD decls fun xs => do
       for mvar in mvars, x in xs do
         mvar.assign x
@@ -971,7 +971,7 @@ def deriveInductionStructural (names : Array Name) (numFixed : Nat) : MetaM Unit
             mkForallFVars ys (.sort levelZero)
         let motiveArities ← infos.mapM fun info => do
           lambdaTelescope (← instantiateLambda info.value xs) fun ys _ => pure ys.size
-        let motiveDecls ← motiveTypes.mapIdxM fun i motiveType => do
+        let motiveDecls ← motiveTypes.mapIdxM fun ⟨i,_⟩ motiveType => do
           let n := if infos.size = 1 then .mkSimple "motive"
                                      else .mkSimple s!"motive_{i+1}"
           pure (n, fun _ => pure motiveType)

src/Lean/Meta/WHNF.lean

@@ -95,7 +95,7 @@ private def toCtorWhenK (recVal : RecursorVal) (major : Expr) : MetaM Expr := do
   let majorType ← inferType major
   let majorType ← instantiateMVars (← whnf majorType)
   let majorTypeI := majorType.getAppFn
-  if !majorTypeI.isConstOf recVal.getMajorInduct then
+  if !majorTypeI.isConstOf recVal.getInduct then
     return major
   else if majorType.hasExprMVar && majorType.getAppArgs[recVal.numParams:].any Expr.hasExprMVar then
     return major
@@ -197,7 +197,7 @@ private def reduceRec (recVal : RecursorVal) (recLvls : List Level) (recArgs : A
       major ← toCtorWhenK recVal major
     major := major.toCtorIfLit
     major ← cleanupNatOffsetMajor major
-    major ← toCtorWhenStructure recVal.getMajorInduct major
+    major ← toCtorWhenStructure recVal.getInduct major
     match getRecRuleFor recVal major with
     | some rule =>
       let majorArgs := major.getAppArgs

src/Lean/Parser/Extra.lean

@@ -189,7 +189,7 @@ open PrettyPrinter Syntax.MonadTraverser Formatter in
 @[combinator_formatter sepByIndent]
 def sepByIndent.formatter (p : Formatter) (_sep : String) (pSep : Formatter) : Formatter := do
   let stx ← getCur
-  let hasNewlineSep := stx.getArgs.mapIdx (fun i n =>
+  let hasNewlineSep := stx.getArgs.mapIdx (fun ⟨i, _⟩ n =>
     i % 2 == 1 && n.matchesNull 0 && i != stx.getArgs.size - 1) |>.any id
   visitArgs do
     for i in (List.range stx.getArgs.size).reverse do

src/Lean/Server/Completion.lean

@@ -1004,7 +1004,7 @@ private def assignSortTexts (completions : CompletionList) : CompletionList := I
   if completions.items.isEmpty then
     return completions
   let items := completions.items.mapIdx fun i item =>
-    { item with sortText? := toString i }
+    { item with sortText? := toString i.val }
   let maxDigits := items[items.size - 1]!.sortText?.get!.length
   let items := items.map fun item =>
     let sortText := item.sortText?.get!

src/kernel/declaration.cpp

@@ -126,6 +126,7 @@ constructor_val::constructor_val(name const & n, names const & lparams, expr con
     object_ref(lean_mk_constructor_val(n.to_obj_arg(), lparams.to_obj_arg(), type.to_obj_arg(), induct.to_obj_arg(),
                                        nat(cidx).to_obj_arg(), nat(nparams).to_obj_arg(), nat(nfields).to_obj_arg(), is_unsafe)) {
 }
+
 bool constructor_val::is_unsafe() const { return lean_constructor_val_is_unsafe(to_obj_arg()); }
 
 extern "C" object * lean_mk_recursor_val(object * n, object * lparams, object * type, object * all,
@@ -142,18 +143,6 @@ recursor_val::recursor_val(name const & n, names const & lparams, expr const & t
                                     nat(nminors).to_obj_arg(), rules.to_obj_arg(), k, is_unsafe)) {
 }
 
-name const & recursor_val::get_major_induct() const {
-    unsigned int n = get_major_idx();
-    expr const * t = &(to_constant_val().get_type());
-    for (unsigned int i = 0; i < n; i++) {
-        t = &(binding_body(*t));
-    }
-    t = &(binding_domain(*t));
-    t = &(get_app_fn(*t));
-    return const_name(*t);
-}
-
-
 bool recursor_val::is_k() const { return lean_recursor_k(to_obj_arg()); }
 bool recursor_val::is_unsafe() const { return lean_recursor_is_unsafe(to_obj_arg()); }
 

src/kernel/declaration.h

@@ -370,7 +370,7 @@ public:
     recursor_val & operator=(recursor_val && other) { object_ref::operator=(std::move(other)); return *this; }
     constant_val const & to_constant_val() const { return static_cast<constant_val const &>(cnstr_get_ref(*this, 0)); }
     name const & get_name() const { return to_constant_val().get_name(); }
-    name const & get_major_induct() const;
+    name const & get_induct() const { return get_name().get_prefix(); }
     names const & get_all() const { return static_cast<names const &>(cnstr_get_ref(*this, 1)); }
     unsigned get_nparams() const { return static_cast<nat const &>(cnstr_get_ref(*this, 2)).get_small_value(); }
     unsigned get_nindices() const { return static_cast<nat const &>(cnstr_get_ref(*this, 3)).get_small_value(); }

src/kernel/expr.cpp

@@ -79,22 +79,21 @@ extern "C" object * lean_lit_type(obj_arg e);
 expr lit_type(literal const & lit) { return expr(lean_lit_type(lit.to_obj_arg())); }
 
 extern "C" uint64_t lean_expr_hash(obj_arg e);
-unsigned hash_core(expr const & e) {
-    return lean_expr_hash(e.to_obj_arg());
+unsigned hash(expr const & e) {
+    object * o = e.raw();
+    unsigned r = static_cast<unsigned>(lean_ctor_get_uint64(o, lean_ctor_num_objs(o)*sizeof(object*)));
+    lean_assert(r == lean_expr_hash(e.to_obj_arg()));
+    return r;
 }
 
 extern "C" uint8 lean_expr_has_fvar(obj_arg e);
-bool has_fvar_core(expr const & e) {
-    return lean_expr_has_fvar(e.to_obj_arg());
-}
+bool has_fvar(expr const & e) { return lean_expr_has_fvar(e.to_obj_arg()); }
 
 extern "C" uint8 lean_expr_has_expr_mvar(obj_arg e);
-bool has_expr_mvar_core(expr const & e) {
-    return lean_expr_has_expr_mvar(e.to_obj_arg());
-}
+bool has_expr_mvar(expr const & e) { return lean_expr_has_expr_mvar(e.to_obj_arg()); }
 
 extern "C" uint8 lean_expr_has_level_mvar(obj_arg e);
-bool has_univ_mvar_core(expr const & e) { return lean_expr_has_level_mvar(e.to_obj_arg()); }
+bool has_univ_mvar(expr const & e) { return lean_expr_has_level_mvar(e.to_obj_arg()); }
 
 extern "C" uint8 lean_expr_has_level_param(obj_arg e);
 bool has_univ_param(expr const & e) { return lean_expr_has_level_param(e.to_obj_arg()); }

src/kernel/expr.h

@@ -123,37 +123,11 @@ inline bool is_eqp(optional<expr> const & a, optional<expr> const & b) {
     return static_cast<bool>(a) == static_cast<bool>(b) && (!a || is_eqp(*a, *b));
 }
 
-inline uint64_t get_data(expr const & e) {
-    return lean_ctor_get_uint64(e.raw(), lean_ctor_num_objs(e.raw())*sizeof(object*));
-}
-/* This is the implementation in Lean */
-unsigned hash_core(expr const & e);
-inline unsigned hash(expr const & e) {
-    unsigned r = static_cast<unsigned>(get_data(e));
-    lean_assert(r == hash_core(e));
-    return r;
-}
-/* This is the implementation in Lean */
-bool has_expr_mvar_core(expr const & e);
-inline bool has_expr_mvar(expr const & e) {
-    bool r = ((get_data(e) >> 41) & 1) == 1;
-    lean_assert(r == has_expr_mvar_core(e)); // ensure the C++ implementation matches the Lean one.
-    return r;
-}
-bool has_univ_mvar_core(expr const & e);
-inline bool has_univ_mvar(expr const & e) {
-    bool r = ((get_data(e) >> 42) & 1) == 1;
-    lean_assert(r == has_univ_mvar_core(e)); // ensure the C++ implementation matches the Lean one.
-    return r;
-}
+unsigned hash(expr const & e);
+bool has_expr_mvar(expr const & e);
+bool has_univ_mvar(expr const & e);
 inline bool has_mvar(expr const & e) { return has_expr_mvar(e) || has_univ_mvar(e); }
-/* This is the implementation in Lean */
-bool has_fvar_core(expr const & e);
-inline bool has_fvar(expr const & e) {
-    bool r = ((get_data(e) >> 40) & 1) == 1;
-    lean_assert(r == has_fvar_core(e)); // ensure the C++ implementation matches the Lean one.
-    return r;
-}
+bool has_fvar(expr const & e);
 bool has_univ_param(expr const & e);
 unsigned get_loose_bvar_range(expr const & e);
 

src/kernel/inductive.h

@@ -33,7 +33,7 @@ inline expr to_cnstr_when_K(environment const & env, recursor_val const & rval,
     lean_assert(rval.is_k());
     expr app_type    = whnf(infer_type(e));
     expr const & app_type_I = get_app_fn(app_type);
-    if (!is_constant(app_type_I) || const_name(app_type_I) != rval.get_major_induct()) return e; // type incorrect
+    if (!is_constant(app_type_I) || const_name(app_type_I) != rval.get_induct()) return e; // type incorrect
     if (has_expr_mvar(app_type)) {
         buffer<expr> app_type_args;
         get_app_args(app_type, app_type_args);
@@ -94,7 +94,7 @@ inline optional<expr> inductive_reduce_rec(environment const & env, expr const &
     else if (is_string_lit(major))
         major = string_lit_to_constructor(major);
     else
-        major = to_cnstr_when_structure(env, rec_val.get_major_induct(), major, whnf, infer_type);
+        major = to_cnstr_when_structure(env, rec_val.get_induct(), major, whnf, infer_type);
     optional<recursor_rule> rule = get_rec_rule_for(rec_val, major);
     if (!rule) return none_expr();
     buffer<expr> major_args;

tests/lean/run/array_isEqvAux.lean

@@ -17,8 +17,6 @@ After unfolding the instances 'instDecidableEqNat', 'Array.instDecidableEq' and
 
 example : #[0, 1] = #[0, 1] := by decide
 
-example : let a := Array.range (10^6); a == a := by native_decide
-
 /-!
 There are other `Array` functions that use well-founded recursion,
 which we've marked as `@[semireducible]`. We test that `decide` can unfold them here.

tests/lean/run/issue5661.lean

@@ -1,73 +0,0 @@
-import Lean.Meta.Basic
-
-inductive StructLike α where
-  | mk : α → StructLike α
-
-inductive Nested where
-  | nest : StructLike Nested → Nested
-  | other
-
-/--
-info: theorem Nested.nest.sizeOf_spec : ∀ (a : StructLike Nested), sizeOf (Nested.nest a) = 1 + sizeOf a :=
-fun a => Eq.refl (1 + sizeOf a)
--/
-#guard_msgs in
-#print Nested.nest.sizeOf_spec
-
-/-- info: StructLike -/
-#guard_msgs in
-open Lean Meta in
-run_meta do
-  let i ← getConstInfoRec ``Nested.rec_1
-  logInfo m!"{i.getMajorInduct}"
-
-theorem works (x : StructLike Nested) : StructLike.rec
-  (motive := fun _ => Bool)
-  (mk := fun _ => true)
-  x = true
-  := rfl
-
-theorem failed_before (x : StructLike Nested) : Nested.rec_1
-  (motive_1 := fun _ => Bool) (motive_2 := fun _ => Bool)
-  (nest := fun _ _ => true)
-  (other := true)
-  (mk := fun _ _ => true)
-  x = true
-  := rfl
-
-
--- The original surface bug
-
-inductive Set (α : Type u) where
-  | mk (l : List α)
-
-inductive Value where
-  | prim
-  | set (s : Set Value)
-
-instance : DecidableEq Value := sorry
-
-mutual
-
-def Value.lt : Value → Value → Bool
-  | .prim, .prim => false
-  | .set (.mk vs₁), .set (.mk vs₂) => Values.lt vs₁ vs₂
-  | .prim, .set _ => true
-  | .set _, .prim => false
-
-def Values.lt : List Value → List Value → Bool
-  | [], [] => false
-  | [], _ => true
-  | _, [] => false
-  | v₁ :: vs₁, v₂ :: vs₂ => Value.lt v₁ v₂ || (v₁ = v₂ && Values.lt vs₁ vs₂)
-
-end
-
-theorem Value.lt_irrefl (v : Value) :
-  ¬ Value.lt v v
-:= by
-  cases v
-  case set a =>
-    show ¬Values.lt a.1 a.1 = true
-    sorry
-  all_goals sorry