Documentation

Init.Data.Array.Basic

Array literal syntax #

Equations
  • One or more equations did not get rendered due to their size.
Instances For
    @[reducible, inline, deprecated Array.toList]
    abbrev Array.data {α : Type u_1} (self : Array α) :
    List α
    Equations
    Instances For

      Preliminary theorems #

      @[simp]
      theorem Array.size_set {α : Type u} (a : Array α) (i : Nat) (v : α) (h : i < a.size) :
      (a.set i v h).size = a.size
      @[simp]
      theorem Array.size_push {α : Type u} (a : Array α) (v : α) :
      (a.push v).size = a.size + 1
      theorem Array.ext {α : Type u} (a b : Array α) (h₁ : a.size = b.size) (h₂ : ∀ (i : Nat) (hi₁ : i < a.size) (hi₂ : i < b.size), a[i] = b[i]) :
      a = b
      theorem Array.ext.extAux {α : Type u} (a b : List α) (h₁ : a.length = b.length) (h₂ : ∀ (i : Nat) (hi₁ : i < a.length) (hi₂ : i < b.length), a.get i, hi₁ = b.get i, hi₂) :
      a = b
      theorem Array.ext' {α : Type u} {as bs : Array α} (h : as.toList = bs.toList) :
      as = bs
      @[simp]
      theorem Array.toArrayAux_eq {α : Type u} (as : List α) (acc : Array α) :
      (as.toArrayAux acc).toList = acc.toList ++ as
      @[simp]
      theorem Array.toList_toArray {α : Type u} (as : List α) :
      as.toArray.toList = as
      @[simp]
      theorem Array.size_toArray {α : Type u} (as : List α) :
      as.toArray.size = as.length
      @[simp]
      theorem Array.getElem_toList {α : Type u} {a : Array α} {i : Nat} (h : i < a.size) :
      a.toList[i] = a[i]
      structure Array.Mem {α : Type u} (as : Array α) (a : α) :

      a ∈ as is a predicate which asserts that a is in the array as.

      • val : a as.toList
      Instances For
        instance Array.instMembership {α : Type u} :
        Equations
        • Array.instMembership = { mem := Array.Mem }
        theorem Array.mem_def {α : Type u} {a : α} {as : Array α} :
        a as a as.toList
        @[simp]
        theorem Array.getElem_mem {α : Type u} {l : Array α} {i : Nat} (h : i < l.size) :
        l[i] l
        @[simp]
        theorem List.toArray_toList {α : Type u} (a : Array α) :
        a.toList.toArray = a
        @[simp]
        theorem List.getElem_toArray {α : Type u} {a : List α} {i : Nat} (h : i < a.toArray.size) :
        a.toArray[i] = a[i]
        @[simp]
        theorem List.getElem?_toArray {α : Type u} {a : List α} {i : Nat} :
        a.toArray[i]? = a[i]?
        @[simp]
        theorem List.getElem!_toArray {α : Type u} [Inhabited α] {a : List α} {i : Nat} :
        a.toArray[i]! = a[i]!
        @[reducible, inline, deprecated Array.toList_toArray]
        abbrev Array.data_toArray {α : Type u_1} (as : List α) :
        as.toArray.toList = as
        Equations
        Instances For
          @[reducible, inline, deprecated Array.toList]
          abbrev Array.Array.data {α : Type u_1} (self : Array α) :
          List α
          Equations
          Instances For

            Externs #

            @[extern lean_array_size]
            def Array.usize {α : Type u} (a : Array α) :

            Low-level version of size that directly queries the C array object cached size. While this is not provable, usize always returns the exact size of the array since the implementation only supports arrays of size less than USize.size.

            Equations
            • a.usize = a.size.toUSize
            Instances For
              @[extern lean_array_uget]
              def Array.uget {α : Type u} (a : Array α) (i : USize) (h : i.toNat < a.size) :
              α

              Low-level version of fget which is as fast as a C array read. Fin values are represented as tag pointers in the Lean runtime. Thus, fget may be slightly slower than uget.

              Equations
              • a.uget i h = a[i.toNat]
              Instances For
                @[extern lean_array_uset]
                def Array.uset {α : Type u} (a : Array α) (i : USize) (v : α) (h : i.toNat < a.size) :

                Low-level version of fset which is as fast as a C array fset. Fin values are represented as tag pointers in the Lean runtime. Thus, fset may be slightly slower than uset.

                Equations
                • a.uset i v h = a.set i.toNat v h
                Instances For
                  @[extern lean_array_pop]
                  def Array.pop {α : Type u} (a : Array α) :
                  Equations
                  • a.pop = { toList := a.toList.dropLast }
                  Instances For
                    @[simp]
                    theorem Array.size_pop {α : Type u} (a : Array α) :
                    a.pop.size = a.size - 1
                    @[extern lean_mk_array]
                    def Array.mkArray {α : Type u} (n : Nat) (v : α) :
                    Equations
                    Instances For
                      @[extern lean_array_fswap]
                      def Array.swap {α : Type u} (a : Array α) (i j : Nat) (hi : i < a.size := by get_elem_tactic) (hj : j < a.size := by get_elem_tactic) :

                      Swaps two entries in an array.

                      This will perform the update destructively provided that a has a reference count of 1 when called.

                      Equations
                      • a.swap i j hi hj = (a.set i a[j] hi).set j a[i]
                      Instances For
                        @[simp]
                        theorem Array.size_swap {α : Type u} (a : Array α) (i j : Nat) {hi : i < a.size} {hj : j < a.size} :
                        (a.swap i j hi hj).size = a.size
                        @[extern lean_array_swap]
                        def Array.swapIfInBounds {α : Type u} (a : Array α) (i j : Nat) :

                        Swaps two entries in an array, or returns the array unchanged if either index is out of bounds.

                        This will perform the update destructively provided that a has a reference count of 1 when called.

                        Equations
                        • a.swapIfInBounds i j = if h₁ : i < a.size then if h₂ : j < a.size then a.swap i j h₁ h₂ else a else a
                        Instances For
                          @[reducible, inline, deprecated Array.swapIfInBounds]
                          abbrev Array.swap! {α : Type u_1} (a : Array α) (i j : Nat) :
                          Equations
                          Instances For

                            GetElem instance for USize, backed by uget #

                            instance Array.instGetElemUSizeLtNatToNatSize {α : Type u} :
                            GetElem (Array α) USize α fun (xs : Array α) (i : USize) => i.toNat < xs.size
                            Equations
                            • Array.instGetElemUSizeLtNatToNatSize = { getElem := fun (xs : Array α) (i : USize) (h : i.toNat < xs.size) => xs.uget i h }

                            Definitions #

                            Equations
                            • Array.instEmptyCollection = { emptyCollection := #[] }
                            instance Array.instInhabited {α : Type u} :
                            Equations
                            • Array.instInhabited = { default := #[] }
                            def Array.isEmpty {α : Type u} (a : Array α) :
                            Equations
                            Instances For
                              @[specialize #[]]
                              def Array.isEqvAux {α : Type u} (a b : Array α) (hsz : a.size = b.size) (p : ααBool) (i : Nat) :
                              i a.sizeBool
                              Equations
                              • a.isEqvAux b hsz p 0 x_2 = true
                              • a.isEqvAux b hsz p i.succ h = (p a[i] b[i] && a.isEqvAux b hsz p i )
                              Instances For
                                @[inline]
                                def Array.isEqv {α : Type u} (a b : Array α) (p : ααBool) :
                                Equations
                                • a.isEqv b p = if h : a.size = b.size then a.isEqvAux b h p a.size else false
                                Instances For
                                  instance Array.instBEq {α : Type u} [BEq α] :
                                  BEq (Array α)
                                  Equations
                                  • Array.instBEq = { beq := fun (a b : Array α) => a.isEqv b BEq.beq }
                                  def Array.ofFn {α : Type u} {n : Nat} (f : Fin nα) :

                                  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)]
                                  
                                  Equations
                                  Instances For
                                    def Array.ofFn.go {α : Type u} {n : Nat} (f : Fin nα) (i : Nat) (acc : Array α) :

                                    Auxiliary for ofFn. ofFn.go f i acc = acc ++ #[f i, ..., f(n - 1)]

                                    Equations
                                    Instances For

                                      The array #[0, 1, ..., n - 1].

                                      Equations
                                      Instances For
                                        def Array.singleton {α : Type u} (v : α) :
                                        Equations
                                        Instances For
                                          def Array.back! {α : Type u} [Inhabited α] (a : Array α) :
                                          α
                                          Equations
                                          • a.back! = a.get! (a.size - 1)
                                          Instances For
                                            @[reducible, inline, deprecated Array.back!]
                                            abbrev Array.back {α : Type u_1} [Inhabited α] (a : Array α) :
                                            α
                                            Equations
                                            Instances For
                                              def Array.get? {α : Type u} (a : Array α) (i : Nat) :
                                              Equations
                                              • a.get? i = if h : i < a.size then some a[i] else none
                                              Instances For
                                                def Array.back? {α : Type u} (a : Array α) :
                                                Equations
                                                • a.back? = a[a.size - 1]?
                                                Instances For
                                                  @[inline]
                                                  def Array.swapAt {α : Type u} (a : Array α) (i : Nat) (v : α) (hi : i < a.size := by get_elem_tactic) :
                                                  α × Array α
                                                  Equations
                                                  • a.swapAt i v hi = (a[i], a.set i v hi)
                                                  Instances For
                                                    @[inline]
                                                    def Array.swapAt! {α : Type u} (a : Array α) (i : Nat) (v : α) :
                                                    α × Array α
                                                    Equations
                                                    • One or more equations did not get rendered due to their size.
                                                    Instances For
                                                      def Array.take {α : Type u} (a : Array α) (n : Nat) :

                                                      take a n returns the first n elements of a.

                                                      Equations
                                                      Instances For
                                                        def Array.take.loop {α : Type u} :
                                                        NatArray αArray α
                                                        Equations
                                                        Instances For
                                                          @[reducible, inline, deprecated Array.take]
                                                          abbrev Array.shrink {α : Type u_1} (a : Array α) (n : Nat) :
                                                          Equations
                                                          Instances For
                                                            @[inline]
                                                            unsafe def Array.modifyMUnsafe {α : Type u} {m : Type u → Type u_1} [Monad m] (a : Array α) (i : Nat) (f : αm α) :
                                                            m (Array α)
                                                            Equations
                                                            • a.modifyMUnsafe i f = if h : i < a.size then let v := a[i]; let a' := a.set i (unsafeCast ()) h; do let vf v pure (a'.set i v ) else pure a
                                                            Instances For
                                                              @[implemented_by Array.modifyMUnsafe]
                                                              def Array.modifyM {α : Type u} {m : Type u → Type u_1} [Monad m] (a : Array α) (i : Nat) (f : αm α) :
                                                              m (Array α)
                                                              Equations
                                                              • a.modifyM i f = if h : i < a.size then let v := a[i]; do let vf v pure (a.set i v h) else pure a
                                                              Instances For
                                                                @[inline]
                                                                def Array.modify {α : Type u} (a : Array α) (i : Nat) (f : αα) :
                                                                Equations
                                                                • a.modify i f = (a.modifyM i f).run
                                                                Instances For
                                                                  @[inline]
                                                                  def Array.modifyOp {α : Type u} (self : Array α) (idx : Nat) (f : αα) :
                                                                  Equations
                                                                  • self.modifyOp idx f = self.modify idx f
                                                                  Instances For
                                                                    @[inline]
                                                                    unsafe def Array.forIn'Unsafe {α : Type u} {β : Type v} {m : Type v → Type w} [Monad m] (as : Array α) (b : β) (f : (a : α) → a asβm (ForInStep β)) :
                                                                    m β

                                                                    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.

                                                                    Equations
                                                                    Instances For
                                                                      @[specialize #[]]
                                                                      unsafe def Array.forIn'Unsafe.loop {α : Type u} {β : Type v} {m : Type v → Type w} [Monad m] (as : Array α) (f : (a : α) → a asβm (ForInStep β)) (sz i : USize) (b : β) :
                                                                      m β
                                                                      Equations
                                                                      • One or more equations did not get rendered due to their size.
                                                                      Instances For
                                                                        @[implemented_by Array.forIn'Unsafe]
                                                                        def Array.forIn' {α : Type u} {β : Type v} {m : Type v → Type w} [Monad m] (as : Array α) (b : β) (f : (a : α) → a asβm (ForInStep β)) :
                                                                        m β

                                                                        Reference implementation for forIn'

                                                                        Equations
                                                                        Instances For
                                                                          def Array.forIn'.loop {α : Type u} {β : Type v} {m : Type v → Type w} [Monad m] (as : Array α) (f : (a : α) → a asβm (ForInStep β)) (i : Nat) (h : i as.size) (b : β) :
                                                                          m β
                                                                          Equations
                                                                          Instances For
                                                                            instance Array.instForIn'InferInstanceMembership {α : Type u} {m : Type u_1 → Type u_2} :
                                                                            ForIn' m (Array α) α inferInstance
                                                                            Equations
                                                                            • Array.instForIn'InferInstanceMembership = { forIn' := fun {β : Type ?u.19} [Monad m] => Array.forIn' }
                                                                            @[inline]
                                                                            unsafe def Array.foldlMUnsafe {α : Type u} {β : Type v} {m : Type v → Type w} [Monad m] (f : βαm β) (init : β) (as : Array α) (start : Nat := 0) (stop : Nat := as.size) :
                                                                            m β

                                                                            See comment at forIn'Unsafe

                                                                            Equations
                                                                            Instances For
                                                                              @[specialize #[]]
                                                                              unsafe def Array.foldlMUnsafe.fold {α : Type u} {β : Type v} {m : Type v → Type w} [Monad m] (f : βαm β) (as : Array α) (i stop : USize) (b : β) :
                                                                              m β
                                                                              Equations
                                                                              Instances For
                                                                                @[implemented_by Array.foldlMUnsafe]
                                                                                def Array.foldlM {α : Type u} {β : Type v} {m : Type v → Type w} [Monad m] (f : βαm β) (init : β) (as : Array α) (start : Nat := 0) (stop : Nat := as.size) :
                                                                                m β

                                                                                Reference implementation for foldlM

                                                                                Equations
                                                                                • One or more equations did not get rendered due to their size.
                                                                                Instances For
                                                                                  def Array.foldlM.loop {α : Type u} {β : Type v} {m : Type v → Type w} [Monad m] (f : βαm β) (as : Array α) (stop : Nat) (h : stop as.size) (i j : Nat) (b : β) :
                                                                                  m β
                                                                                  Equations
                                                                                  • One or more equations did not get rendered due to their size.
                                                                                  Instances For
                                                                                    @[inline]
                                                                                    unsafe def Array.foldrMUnsafe {α : Type u} {β : Type v} {m : Type v → Type w} [Monad m] (f : αβm β) (init : β) (as : Array α) (start : Nat := as.size) (stop : Nat := 0) :
                                                                                    m β

                                                                                    See comment at forIn'Unsafe

                                                                                    Equations
                                                                                    • One or more equations did not get rendered due to their size.
                                                                                    Instances For
                                                                                      @[specialize #[]]
                                                                                      unsafe def Array.foldrMUnsafe.fold {α : Type u} {β : Type v} {m : Type v → Type w} [Monad m] (f : αβm β) (as : Array α) (i stop : USize) (b : β) :
                                                                                      m β
                                                                                      Equations
                                                                                      Instances For
                                                                                        @[implemented_by Array.foldrMUnsafe]
                                                                                        def Array.foldrM {α : Type u} {β : Type v} {m : Type v → Type w} [Monad m] (f : αβm β) (init : β) (as : Array α) (start : Nat := as.size) (stop : Nat := 0) :
                                                                                        m β

                                                                                        Reference implementation for foldrM

                                                                                        Equations
                                                                                        • One or more equations did not get rendered due to their size.
                                                                                        Instances For
                                                                                          def Array.foldrM.fold {α : Type u} {β : Type v} {m : Type v → Type w} [Monad m] (f : αβm β) (as : Array α) (stop : Nat := 0) (i : Nat) (h : i as.size) (b : β) :
                                                                                          m β
                                                                                          Equations
                                                                                          Instances For
                                                                                            @[inline]
                                                                                            unsafe def Array.mapMUnsafe {α : Type u} {β : Type v} {m : Type v → Type w} [Monad m] (f : αm β) (as : Array α) :
                                                                                            m (Array β)

                                                                                            See comment at forIn'Unsafe

                                                                                            Equations
                                                                                            Instances For
                                                                                              @[specialize #[]]
                                                                                              unsafe def Array.mapMUnsafe.map {α : Type u} {β : Type v} {m : Type v → Type w} [Monad m] (f : αm β) (sz i : USize) (r : Array NonScalar) :
                                                                                              Equations
                                                                                              • One or more equations did not get rendered due to their size.
                                                                                              Instances For
                                                                                                @[implemented_by Array.mapMUnsafe]
                                                                                                def Array.mapM {α : Type u} {β : Type v} {m : Type v → Type w} [Monad m] (f : αm β) (as : Array α) :
                                                                                                m (Array β)

                                                                                                Reference implementation for mapM

                                                                                                Equations
                                                                                                Instances For
                                                                                                  def Array.mapM.map {α : Type u} {β : Type v} {m : Type v → Type w} [Monad m] (f : αm β) (as : Array α) (i : Nat) (r : Array β) :
                                                                                                  m (Array β)
                                                                                                  Equations
                                                                                                  Instances For
                                                                                                    @[reducible, inline, deprecated Array.mapM]
                                                                                                    abbrev Array.sequenceMap {α : Type u_1} {β : Type u_2} {m : Type u_2 → Type u_3} [Monad m] (f : αm β) (as : Array α) :
                                                                                                    m (Array β)
                                                                                                    Equations
                                                                                                    Instances For
                                                                                                      @[inline]
                                                                                                      def Array.mapFinIdxM {α : Type u} {β : Type v} {m : Type v → Type w} [Monad m] (as : Array α) (f : Fin as.sizeαm β) :
                                                                                                      m (Array β)

                                                                                                      Variant of mapIdxM which receives the index as a Fin as.size.

                                                                                                      Equations
                                                                                                      Instances For
                                                                                                        @[specialize #[]]
                                                                                                        def Array.mapFinIdxM.map {α : Type u} {β : Type v} {m : Type v → Type w} [Monad m] (as : Array α) (f : Fin as.sizeαm β) (i j : Nat) (inv : i + j = as.size) (bs : Array β) :
                                                                                                        m (Array β)
                                                                                                        Equations
                                                                                                        Instances For
                                                                                                          @[inline]
                                                                                                          def Array.mapIdxM {α : Type u} {β : Type v} {m : Type v → Type w} [Monad m] (f : Natαm β) (as : Array α) :
                                                                                                          m (Array β)
                                                                                                          Equations
                                                                                                          Instances For
                                                                                                            @[inline]
                                                                                                            def Array.findSomeM? {α : Type u} {β : Type v} {m : Type v → Type w} [Monad m] (f : αm (Option β)) (as : Array α) :
                                                                                                            m (Option β)
                                                                                                            Equations
                                                                                                            • One or more equations did not get rendered due to their size.
                                                                                                            Instances For
                                                                                                              @[inline]
                                                                                                              def Array.findM? {α : Type} {m : TypeType} [Monad m] (p : αm Bool) (as : Array α) :
                                                                                                              m (Option α)
                                                                                                              Equations
                                                                                                              • One or more equations did not get rendered due to their size.
                                                                                                              Instances For
                                                                                                                @[inline]
                                                                                                                def Array.findIdxM? {α : Type u} {m : TypeType u_1} [Monad m] (p : αm Bool) (as : Array α) :
                                                                                                                Equations
                                                                                                                • One or more equations did not get rendered due to their size.
                                                                                                                Instances For
                                                                                                                  @[inline]
                                                                                                                  unsafe def Array.anyMUnsafe {α : Type u} {m : TypeType w} [Monad m] (p : αm Bool) (as : Array α) (start : Nat := 0) (stop : Nat := as.size) :
                                                                                                                  Equations
                                                                                                                  • One or more equations did not get rendered due to their size.
                                                                                                                  Instances For
                                                                                                                    @[specialize #[]]
                                                                                                                    unsafe def Array.anyMUnsafe.any {α : Type u} {m : TypeType w} [Monad m] (p : αm Bool) (as : Array α) (i stop : USize) :
                                                                                                                    Equations
                                                                                                                    • One or more equations did not get rendered due to their size.
                                                                                                                    Instances For
                                                                                                                      @[implemented_by Array.anyMUnsafe]
                                                                                                                      def Array.anyM {α : Type u} {m : TypeType w} [Monad m] (p : αm Bool) (as : Array α) (start : Nat := 0) (stop : Nat := as.size) :
                                                                                                                      Equations
                                                                                                                      • One or more equations did not get rendered due to their size.
                                                                                                                      Instances For
                                                                                                                        def Array.anyM.loop {α : Type u} {m : TypeType w} [Monad m] (p : αm Bool) (as : Array α) (stop : Nat) (h : stop as.size) (j : Nat) :
                                                                                                                        Equations
                                                                                                                        • One or more equations did not get rendered due to their size.
                                                                                                                        Instances For
                                                                                                                          @[inline]
                                                                                                                          def Array.allM {α : Type u} {m : TypeType w} [Monad m] (p : αm Bool) (as : Array α) (start : Nat := 0) (stop : Nat := as.size) :
                                                                                                                          Equations
                                                                                                                          Instances For
                                                                                                                            @[inline]
                                                                                                                            def Array.findSomeRevM? {α : Type u} {β : Type v} {m : Type v → Type w} [Monad m] (f : αm (Option β)) (as : Array α) :
                                                                                                                            m (Option β)
                                                                                                                            Equations
                                                                                                                            Instances For
                                                                                                                              @[specialize #[]]
                                                                                                                              def Array.findSomeRevM?.find {α : Type u} {β : Type v} {m : Type v → Type w} [Monad m] (f : αm (Option β)) (as : Array α) (i : Nat) :
                                                                                                                              i as.sizem (Option β)
                                                                                                                              Equations
                                                                                                                              Instances For
                                                                                                                                @[inline]
                                                                                                                                def Array.findRevM? {α : Type} {m : TypeType w} [Monad m] (p : αm Bool) (as : Array α) :
                                                                                                                                m (Option α)
                                                                                                                                Equations
                                                                                                                                Instances For
                                                                                                                                  @[inline]
                                                                                                                                  def Array.forM {α : Type u} {m : Type v → Type w} [Monad m] (f : αm PUnit) (as : Array α) (start : Nat := 0) (stop : Nat := as.size) :
                                                                                                                                  Equations
                                                                                                                                  Instances For
                                                                                                                                    @[inline]
                                                                                                                                    def Array.forRevM {α : Type u} {m : Type v → Type w} [Monad m] (f : αm PUnit) (as : Array α) (start : Nat := as.size) (stop : Nat := 0) :
                                                                                                                                    Equations
                                                                                                                                    Instances For
                                                                                                                                      @[inline]
                                                                                                                                      def Array.foldl {α : Type u} {β : Type v} (f : βαβ) (init : β) (as : Array α) (start : Nat := 0) (stop : Nat := as.size) :
                                                                                                                                      β
                                                                                                                                      Equations
                                                                                                                                      Instances For
                                                                                                                                        @[inline]
                                                                                                                                        def Array.foldr {α : Type u} {β : Type v} (f : αββ) (init : β) (as : Array α) (start : Nat := as.size) (stop : Nat := 0) :
                                                                                                                                        β
                                                                                                                                        Equations
                                                                                                                                        Instances For
                                                                                                                                          @[inline]
                                                                                                                                          def Array.map {α : Type u} {β : Type v} (f : αβ) (as : Array α) :
                                                                                                                                          Equations
                                                                                                                                          Instances For
                                                                                                                                            @[inline]
                                                                                                                                            def Array.mapFinIdx {α : Type u} {β : Type v} (as : Array α) (f : Fin as.sizeαβ) :

                                                                                                                                            Variant of mapIdx which receives the index as a Fin as.size.

                                                                                                                                            Equations
                                                                                                                                            • as.mapFinIdx f = (as.mapFinIdxM f).run
                                                                                                                                            Instances For
                                                                                                                                              @[inline]
                                                                                                                                              def Array.mapIdx {α : Type u} {β : Type v} (f : Natαβ) (as : Array α) :
                                                                                                                                              Equations
                                                                                                                                              Instances For
                                                                                                                                                def Array.zipWithIndex {α : Type u} (arr : Array α) :
                                                                                                                                                Array (α × Nat)

                                                                                                                                                Turns #[a, b] into #[(a, 0), (b, 1)].

                                                                                                                                                Equations
                                                                                                                                                Instances For
                                                                                                                                                  @[inline]
                                                                                                                                                  def Array.find? {α : Type} (p : αBool) (as : Array α) :
                                                                                                                                                  Equations
                                                                                                                                                  Instances For
                                                                                                                                                    @[inline]
                                                                                                                                                    def Array.findSome? {α : Type u} {β : Type v} (f : αOption β) (as : Array α) :
                                                                                                                                                    Equations
                                                                                                                                                    Instances For
                                                                                                                                                      @[inline]
                                                                                                                                                      def Array.findSome! {α : Type u} {β : Type v} [Inhabited β] (f : αOption β) (a : Array α) :
                                                                                                                                                      β
                                                                                                                                                      Equations
                                                                                                                                                      Instances For
                                                                                                                                                        @[inline]
                                                                                                                                                        def Array.findSomeRev? {α : Type u} {β : Type v} (f : αOption β) (as : Array α) :
                                                                                                                                                        Equations
                                                                                                                                                        Instances For
                                                                                                                                                          @[inline]
                                                                                                                                                          def Array.findRev? {α : Type} (p : αBool) (as : Array α) :
                                                                                                                                                          Equations
                                                                                                                                                          Instances For
                                                                                                                                                            @[inline]
                                                                                                                                                            def Array.findIdx? {α : Type u} (p : αBool) (as : Array α) :
                                                                                                                                                            Equations
                                                                                                                                                            Instances For
                                                                                                                                                              def Array.findIdx?.loop {α : Type u} (p : αBool) (as : Array α) (j : Nat) :
                                                                                                                                                              Equations
                                                                                                                                                              Instances For
                                                                                                                                                                @[inline]
                                                                                                                                                                def Array.findFinIdx? {α : Type u} (p : αBool) (as : Array α) :
                                                                                                                                                                Option (Fin as.size)
                                                                                                                                                                Equations
                                                                                                                                                                Instances For
                                                                                                                                                                  def Array.findFinIdx?.loop {α : Type u} (p : αBool) (as : Array α) (j : Nat) :
                                                                                                                                                                  Option (Fin as.size)
                                                                                                                                                                  Equations
                                                                                                                                                                  Instances For
                                                                                                                                                                    def Array.indexOfAux {α : Type u} [BEq α] (a : Array α) (v : α) (i : Nat) :
                                                                                                                                                                    Option (Fin a.size)
                                                                                                                                                                    Equations
                                                                                                                                                                    • a.indexOfAux v i = if h : i < a.size then if (a[i] == v) = true then some i, h else a.indexOfAux v (i + 1) else none
                                                                                                                                                                    Instances For
                                                                                                                                                                      def Array.indexOf? {α : Type u} [BEq α] (a : Array α) (v : α) :
                                                                                                                                                                      Option (Fin a.size)
                                                                                                                                                                      Equations
                                                                                                                                                                      • a.indexOf? v = a.indexOfAux v 0
                                                                                                                                                                      Instances For
                                                                                                                                                                        @[deprecated Array.indexOf?]
                                                                                                                                                                        def Array.getIdx? {α : Type u} [BEq α] (a : Array α) (v : α) :
                                                                                                                                                                        Equations
                                                                                                                                                                        Instances For
                                                                                                                                                                          @[inline]
                                                                                                                                                                          def Array.any {α : Type u} (as : Array α) (p : αBool) (start : Nat := 0) (stop : Nat := as.size) :
                                                                                                                                                                          Equations
                                                                                                                                                                          Instances For
                                                                                                                                                                            @[inline]
                                                                                                                                                                            def Array.all {α : Type u} (as : Array α) (p : αBool) (start : Nat := 0) (stop : Nat := as.size) :
                                                                                                                                                                            Equations
                                                                                                                                                                            Instances For
                                                                                                                                                                              def Array.contains {α : Type u} [BEq α] (as : Array α) (a : α) :
                                                                                                                                                                              Equations
                                                                                                                                                                              • as.contains a = as.any fun (x : α) => x == a
                                                                                                                                                                              Instances For
                                                                                                                                                                                def Array.elem {α : Type u} [BEq α] (a : α) (as : Array α) :
                                                                                                                                                                                Equations
                                                                                                                                                                                Instances For
                                                                                                                                                                                  @[export lean_array_to_list_impl]
                                                                                                                                                                                  def Array.toListImpl {α : Type u} (as : Array α) :
                                                                                                                                                                                  List α

                                                                                                                                                                                  Convert a Array α into an List α. This is O(n) in the size of the array.

                                                                                                                                                                                  Equations
                                                                                                                                                                                  Instances For
                                                                                                                                                                                    @[inline]
                                                                                                                                                                                    def Array.toListAppend {α : Type u} (as : Array α) (l : List α) :
                                                                                                                                                                                    List α

                                                                                                                                                                                    Prepends an Array α onto the front of a list. Equivalent to as.toList ++ l.

                                                                                                                                                                                    Equations
                                                                                                                                                                                    Instances For
                                                                                                                                                                                      def Array.append {α : Type u} (as bs : Array α) :
                                                                                                                                                                                      Equations
                                                                                                                                                                                      Instances For
                                                                                                                                                                                        instance Array.instAppend {α : Type u} :
                                                                                                                                                                                        Equations
                                                                                                                                                                                        • Array.instAppend = { append := Array.append }
                                                                                                                                                                                        def Array.appendList {α : Type u} (as : Array α) (bs : List α) :
                                                                                                                                                                                        Equations
                                                                                                                                                                                        Instances For
                                                                                                                                                                                          instance Array.instHAppendList {α : Type u} :
                                                                                                                                                                                          HAppend (Array α) (List α) (Array α)
                                                                                                                                                                                          Equations
                                                                                                                                                                                          • Array.instHAppendList = { hAppend := Array.appendList }
                                                                                                                                                                                          @[inline]
                                                                                                                                                                                          def Array.flatMapM {α : Type u} {m : Type u_1 → Type u_2} {β : Type u_1} [Monad m] (f : αm (Array β)) (as : Array α) :
                                                                                                                                                                                          m (Array β)
                                                                                                                                                                                          Equations
                                                                                                                                                                                          Instances For
                                                                                                                                                                                            @[reducible, inline, deprecated Array.flatMapM]
                                                                                                                                                                                            abbrev Array.concatMapM {α : Type u_1} {m : Type u_2 → Type u_3} {β : Type u_2} [Monad m] (f : αm (Array β)) (as : Array α) :
                                                                                                                                                                                            m (Array β)
                                                                                                                                                                                            Equations
                                                                                                                                                                                            Instances For
                                                                                                                                                                                              @[inline]
                                                                                                                                                                                              def Array.flatMap {α : Type u} {β : Type u_1} (f : αArray β) (as : Array α) :
                                                                                                                                                                                              Equations
                                                                                                                                                                                              Instances For
                                                                                                                                                                                                @[reducible, inline, deprecated Array.flatMap]
                                                                                                                                                                                                abbrev Array.concatMap {α : Type u_1} {β : Type u_2} (f : αArray β) (as : Array α) :
                                                                                                                                                                                                Equations
                                                                                                                                                                                                Instances For
                                                                                                                                                                                                  @[inline]
                                                                                                                                                                                                  def Array.flatten {α : Type u} (as : Array (Array α)) :

                                                                                                                                                                                                  Joins array of array into a single array.

                                                                                                                                                                                                  flatten #[#[a₁, a₂, ⋯], #[b₁, b₂, ⋯], ⋯] = #[a₁, a₂, ⋯, b₁, b₂, ⋯]

                                                                                                                                                                                                  Equations
                                                                                                                                                                                                  Instances For
                                                                                                                                                                                                    @[inline]
                                                                                                                                                                                                    def Array.filter {α : Type u} (p : αBool) (as : Array α) (start : Nat := 0) (stop : Nat := as.size) :
                                                                                                                                                                                                    Equations
                                                                                                                                                                                                    Instances For
                                                                                                                                                                                                      @[inline]
                                                                                                                                                                                                      def Array.filterM {m : TypeType u_1} {α : Type} [Monad m] (p : αm Bool) (as : Array α) (start : Nat := 0) (stop : Nat := as.size) :
                                                                                                                                                                                                      m (Array α)
                                                                                                                                                                                                      Equations
                                                                                                                                                                                                      Instances For
                                                                                                                                                                                                        @[specialize #[]]
                                                                                                                                                                                                        def Array.filterMapM {α : Type u} {m : Type u_1 → Type u_2} {β : Type u_1} [Monad m] (f : αm (Option β)) (as : Array α) (start : Nat := 0) (stop : Nat := as.size) :
                                                                                                                                                                                                        m (Array β)
                                                                                                                                                                                                        Equations
                                                                                                                                                                                                        • One or more equations did not get rendered due to their size.
                                                                                                                                                                                                        Instances For
                                                                                                                                                                                                          @[inline]
                                                                                                                                                                                                          def Array.filterMap {α : Type u} {β : Type u_1} (f : αOption β) (as : Array α) (start : Nat := 0) (stop : Nat := as.size) :
                                                                                                                                                                                                          Equations
                                                                                                                                                                                                          Instances For
                                                                                                                                                                                                            @[specialize #[]]
                                                                                                                                                                                                            def Array.getMax? {α : Type u} (as : Array α) (lt : ααBool) :
                                                                                                                                                                                                            Equations
                                                                                                                                                                                                            • as.getMax? lt = if h : 0 < as.size then let a0 := as[0]; some (Array.foldl (fun (best a : α) => if lt best a = true then a else best) a0 as 1) else none
                                                                                                                                                                                                            Instances For
                                                                                                                                                                                                              @[inline]
                                                                                                                                                                                                              def Array.partition {α : Type u} (p : αBool) (as : Array α) :
                                                                                                                                                                                                              Array α × Array α
                                                                                                                                                                                                              Equations
                                                                                                                                                                                                              • One or more equations did not get rendered due to their size.
                                                                                                                                                                                                              Instances For
                                                                                                                                                                                                                def Array.reverse {α : Type u} (as : Array α) :
                                                                                                                                                                                                                Equations
                                                                                                                                                                                                                Instances For
                                                                                                                                                                                                                  theorem Array.reverse.termination {i j : Nat} (h : i < j) :
                                                                                                                                                                                                                  j - 1 - (i + 1) < j - i
                                                                                                                                                                                                                  @[irreducible]
                                                                                                                                                                                                                  def Array.reverse.loop {α : Type u} (as : Array α) (i : Nat) (j : Fin as.size) :
                                                                                                                                                                                                                  Equations
                                                                                                                                                                                                                  Instances For
                                                                                                                                                                                                                    def Array.popWhile {α : Type u} (p : αBool) (as : Array α) :
                                                                                                                                                                                                                    Equations
                                                                                                                                                                                                                    Instances For
                                                                                                                                                                                                                      def Array.takeWhile {α : Type u} (p : αBool) (as : Array α) :
                                                                                                                                                                                                                      Equations
                                                                                                                                                                                                                      Instances For
                                                                                                                                                                                                                        def Array.takeWhile.go {α : Type u} (p : αBool) (as : Array α) (i : Nat) (r : Array α) :
                                                                                                                                                                                                                        Equations
                                                                                                                                                                                                                        Instances For
                                                                                                                                                                                                                          def Array.eraseIdx {α : Type u} (a : Array α) (i : Nat) (h : i < a.size := by get_elem_tactic) :

                                                                                                                                                                                                                          Remove the element at a given index from an array without a runtime bounds checks, using a Nat index and a tactic-provided bound.

                                                                                                                                                                                                                          This function takes worst case O(n) time because it has to backshift all elements at positions greater than i.

                                                                                                                                                                                                                          Equations
                                                                                                                                                                                                                          • a.eraseIdx i h = if h' : i + 1 < a.size then let a' := a.swap (i + 1) i h' h; a'.eraseIdx (i + 1) else a.pop
                                                                                                                                                                                                                          Instances For
                                                                                                                                                                                                                            @[simp]
                                                                                                                                                                                                                            theorem Array.size_eraseIdx {α : Type u} (a : Array α) (i : Nat) (h : i < a.size) :
                                                                                                                                                                                                                            (a.eraseIdx i h).size = a.size - 1
                                                                                                                                                                                                                            def Array.eraseIdxIfInBounds {α : Type u} (a : Array α) (i : Nat) :

                                                                                                                                                                                                                            Remove the element at a given index from an array, or do nothing if the index is out of bounds.

                                                                                                                                                                                                                            This function takes worst case O(n) time because it has to backshift all elements at positions greater than i.

                                                                                                                                                                                                                            Equations
                                                                                                                                                                                                                            • a.eraseIdxIfInBounds i = if h : i < a.size then a.eraseIdx i h else a
                                                                                                                                                                                                                            Instances For
                                                                                                                                                                                                                              def Array.eraseIdx! {α : Type u} (a : Array α) (i : Nat) :

                                                                                                                                                                                                                              Remove the element at a given index from an array, or panic if the index is out of bounds.

                                                                                                                                                                                                                              This function takes worst case O(n) time because it has to backshift all elements at positions greater than i.

                                                                                                                                                                                                                              Equations
                                                                                                                                                                                                                              • a.eraseIdx! i = if h : i < a.size then a.eraseIdx i h else panicWithPosWithDecl "Init.Data.Array.Basic" "Array.eraseIdx!" 821 45 "invalid index"
                                                                                                                                                                                                                              Instances For
                                                                                                                                                                                                                                def Array.erase {α : Type u} [BEq α] (as : Array α) (a : α) :
                                                                                                                                                                                                                                Equations
                                                                                                                                                                                                                                • as.erase a = match as.indexOf? a with | none => as | some i => as.eraseIdx i
                                                                                                                                                                                                                                Instances For
                                                                                                                                                                                                                                  def Array.eraseP {α : Type u} (as : Array α) (p : αBool) :

                                                                                                                                                                                                                                  Erase the first element that satisfies the predicate p.

                                                                                                                                                                                                                                  Equations
                                                                                                                                                                                                                                  Instances For
                                                                                                                                                                                                                                    @[inline]
                                                                                                                                                                                                                                    def Array.insertIdx {α : Type u} (as : Array α) (i : Nat) (a : α) :
                                                                                                                                                                                                                                    autoParam (i as.size) _auto✝Array α

                                                                                                                                                                                                                                    Insert element a at position i.

                                                                                                                                                                                                                                    Equations
                                                                                                                                                                                                                                    Instances For
                                                                                                                                                                                                                                      def Array.insertIdx.loop {α : Type u} (i : Nat) (as : Array α) (j : Fin as.size) :
                                                                                                                                                                                                                                      Equations
                                                                                                                                                                                                                                      Instances For
                                                                                                                                                                                                                                        @[reducible, inline, deprecated Array.insertIdx]
                                                                                                                                                                                                                                        abbrev Array.insertAt {α : Type u_1} (as : Array α) (i : Nat) (a : α) :
                                                                                                                                                                                                                                        autoParam (i as.size) _auto✝Array α
                                                                                                                                                                                                                                        Equations
                                                                                                                                                                                                                                        Instances For
                                                                                                                                                                                                                                          def Array.insertIdx! {α : Type u} (as : Array α) (i : Nat) (a : α) :

                                                                                                                                                                                                                                          Insert element a at position i. Panics if i is not i ≤ as.size.

                                                                                                                                                                                                                                          Equations
                                                                                                                                                                                                                                          • as.insertIdx! i a = if h : i as.size then as.insertIdx i a h else panicWithPosWithDecl "Init.Data.Array.Basic" "Array.insertIdx!" 855 7 "invalid index"
                                                                                                                                                                                                                                          Instances For
                                                                                                                                                                                                                                            @[reducible, inline, deprecated Array.insertIdx!]
                                                                                                                                                                                                                                            abbrev Array.insertAt! {α : Type u_1} (as : Array α) (i : Nat) (a : α) :
                                                                                                                                                                                                                                            Equations
                                                                                                                                                                                                                                            Instances For
                                                                                                                                                                                                                                              def Array.insertIdxIfInBounds {α : Type u} (as : Array α) (i : Nat) (a : α) :

                                                                                                                                                                                                                                              Insert element a at position i, or do nothing if as.size < i.

                                                                                                                                                                                                                                              Equations
                                                                                                                                                                                                                                              • as.insertIdxIfInBounds i a = if h : i as.size then as.insertIdx i a h else as
                                                                                                                                                                                                                                              Instances For
                                                                                                                                                                                                                                                def Array.isPrefixOfAux {α : Type u} [BEq α] (as bs : Array α) (hle : as.size bs.size) (i : Nat) :
                                                                                                                                                                                                                                                Equations
                                                                                                                                                                                                                                                • as.isPrefixOfAux bs hle i = if h : i < as.size then let a := as[i]; let_fun this := ; let b := bs[i]; if (a == b) = true then as.isPrefixOfAux bs hle (i + 1) else false else true
                                                                                                                                                                                                                                                Instances For
                                                                                                                                                                                                                                                  def Array.isPrefixOf {α : Type u} [BEq α] (as bs : Array α) :

                                                                                                                                                                                                                                                  Return true iff as is a prefix of bs. That is, bs = as ++ t for some t : List α.

                                                                                                                                                                                                                                                  Equations
                                                                                                                                                                                                                                                  • as.isPrefixOf bs = if h : as.size bs.size then as.isPrefixOfAux bs h 0 else false
                                                                                                                                                                                                                                                  Instances For
                                                                                                                                                                                                                                                    @[specialize #[]]
                                                                                                                                                                                                                                                    def Array.zipWithAux {α : Type u} {β : Type u_1} {γ : Type u_2} (as : Array α) (bs : Array β) (f : αβγ) (i : Nat) (cs : Array γ) :
                                                                                                                                                                                                                                                    Equations
                                                                                                                                                                                                                                                    • as.zipWithAux bs f i cs = if h : i < as.size then let a := as[i]; if h : i < bs.size then let b := bs[i]; as.zipWithAux bs f (i + 1) (cs.push (f a b)) else cs else cs
                                                                                                                                                                                                                                                    Instances For
                                                                                                                                                                                                                                                      @[inline]
                                                                                                                                                                                                                                                      def Array.zipWith {α : Type u} {β : Type u_1} {γ : Type u_2} (as : Array α) (bs : Array β) (f : αβγ) :
                                                                                                                                                                                                                                                      Equations
                                                                                                                                                                                                                                                      • as.zipWith bs f = as.zipWithAux bs f 0 #[]
                                                                                                                                                                                                                                                      Instances For
                                                                                                                                                                                                                                                        def Array.zip {α : Type u} {β : Type u_1} (as : Array α) (bs : Array β) :
                                                                                                                                                                                                                                                        Array (α × β)
                                                                                                                                                                                                                                                        Equations
                                                                                                                                                                                                                                                        • as.zip bs = as.zipWith bs Prod.mk
                                                                                                                                                                                                                                                        Instances For
                                                                                                                                                                                                                                                          def Array.zipWithAll {α : Type u} {β : Type u_1} {γ : Type u_2} (as : Array α) (bs : Array β) (f : Option αOption βγ) :
                                                                                                                                                                                                                                                          Equations
                                                                                                                                                                                                                                                          Instances For
                                                                                                                                                                                                                                                            @[irreducible]
                                                                                                                                                                                                                                                            def Array.zipWithAll.go {α : Type u} {β : Type u_1} {γ : Type u_2} (f : Option αOption βγ) (as : Array α) (bs : Array β) (i : Nat) (cs : Array γ) :
                                                                                                                                                                                                                                                            Equations
                                                                                                                                                                                                                                                            Instances For
                                                                                                                                                                                                                                                              def Array.unzip {α : Type u} {β : Type u_1} (as : Array (α × β)) :
                                                                                                                                                                                                                                                              Array α × Array β
                                                                                                                                                                                                                                                              Equations
                                                                                                                                                                                                                                                              • as.unzip = Array.foldl (fun (x : Array α × Array β) (x_1 : α × β) => match x with | (as, bs) => match x_1 with | (a, b) => (as.push a, bs.push b)) (#[], #[]) as
                                                                                                                                                                                                                                                              Instances For
                                                                                                                                                                                                                                                                @[deprecated Array.partition]
                                                                                                                                                                                                                                                                def Array.split {α : Type u} (as : Array α) (p : αBool) :
                                                                                                                                                                                                                                                                Array α × Array α
                                                                                                                                                                                                                                                                Equations
                                                                                                                                                                                                                                                                • as.split p = Array.foldl (fun (x : Array α × Array α) (a : α) => match x with | (as, bs) => if p a = true then (as.push a, bs) else (as, bs.push a)) (#[], #[]) as
                                                                                                                                                                                                                                                                Instances For

                                                                                                                                                                                                                                                                  Auxiliary functions used in metaprogramming. #

                                                                                                                                                                                                                                                                  We do not currently intend to provide verification theorems for these functions.

                                                                                                                                                                                                                                                                  @[inline]
                                                                                                                                                                                                                                                                  def Array.reduceOption {α : Type u} (as : Array (Option α)) :

                                                                                                                                                                                                                                                                  Drop nones from a Array, and replace each remaining some a with a.

                                                                                                                                                                                                                                                                  Equations
                                                                                                                                                                                                                                                                  Instances For

                                                                                                                                                                                                                                                                    eraseReps #

                                                                                                                                                                                                                                                                    def Array.eraseReps {α : Type u_1} [BEq α] (as : Array α) :

                                                                                                                                                                                                                                                                    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]
                                                                                                                                                                                                                                                                    Equations
                                                                                                                                                                                                                                                                    • One or more equations did not get rendered due to their size.
                                                                                                                                                                                                                                                                    Instances For

                                                                                                                                                                                                                                                                      allDiff #

                                                                                                                                                                                                                                                                      def Array.allDiff {α : Type u} [BEq α] (as : Array α) :
                                                                                                                                                                                                                                                                      Equations
                                                                                                                                                                                                                                                                      Instances For

                                                                                                                                                                                                                                                                        getEvenElems #

                                                                                                                                                                                                                                                                        @[inline]
                                                                                                                                                                                                                                                                        def Array.getEvenElems {α : Type u} (as : Array α) :
                                                                                                                                                                                                                                                                        Equations
                                                                                                                                                                                                                                                                        • One or more equations did not get rendered due to their size.
                                                                                                                                                                                                                                                                        Instances For

                                                                                                                                                                                                                                                                          Repr and ToString #

                                                                                                                                                                                                                                                                          instance Array.instRepr {α : Type u} [Repr α] :
                                                                                                                                                                                                                                                                          Repr (Array α)
                                                                                                                                                                                                                                                                          Equations
                                                                                                                                                                                                                                                                          • One or more equations did not get rendered due to their size.
                                                                                                                                                                                                                                                                          instance Array.instToString {α : Type u} [ToString α] :
                                                                                                                                                                                                                                                                          Equations
                                                                                                                                                                                                                                                                          • Array.instToString = { toString := fun (a : Array α) => "#" ++ toString a.toList }