theorem Array.of_push_eq_push {α : Type u_1} {a b : α} {as bs : Array α} (h : as.push a = bs.push b) : as = bs ∧ a = b

theorem List.toArray_eq_toArray_eq {α : Type u_1} {as bs : List α} : (as.toArray = bs.toArray) = (as = bs)

def Array.mapM' {m : Type u_1 → Type u_2} {α : Type u_3} {β : Type u_1} [Monad m] (f : α → m β) (as : Array α) : m { bs : Array β // bs.size = as.size }

Applies the monadic action f to every element in the array, left-to-right, and returns the array of results. Furthermore, the resulting array's type guarantees that it contains the same number of elements as the input array.

Equations

• Array.mapM' f as = Array.mapM'.go f as 0 ⟨Array.mkEmpty as.size, ⋯⟩ ⋯

@[irreducible]

def Array.mapM'.go {m : Type u_1 → Type u_2} {α : Type u_3} {β : Type u_1} [Monad m] (f : α → m β) (as : Array α) (i : Nat) (acc : { bs : Array β // bs.size = i }) (hle : i ≤ as.size) : m { bs : Array β // bs.size = as.size }

Equations

• Array.mapM'.go f as i acc hle = if h : i = as.size then pure (h ▸ acc) else have hlt := ⋯; do let b ← f as[i] Array.mapM'.go f as (i + 1) ⟨acc.val.push b, ⋯⟩ hlt

@[implemented_by _private.Init.Data.Array.BasicAux.0.mapMonoMImp]

def Array.mapMonoM {m : Type u_1 → Type u_2} {α : Type u_1} [Monad m] (as : Array α) (f : α → m α) : m (Array α)

Applies a monadic function to each element of an array, returning the array of results. The function is monomorphic: it is required to return a value of the same type. The internal implementation uses pointer equality, and does not allocate a new array if the result of each function call is pointer-equal to its argument.

Equations

• as.mapMonoM f = Array.mapM f as

@[inline]

def Array.mapMono {α : Type u_1} (as : Array α) (f : α → α) : Array α

Applies a function to each element of an array, returning the array of results. The function is monomorphic: it is required to return a value of the same type. The internal implementation uses pointer equality, and does not allocate a new array if the result of each function call is pointer-equal to its argument.

Equations

• as.mapMono f = (as.mapMonoM fun (x : α) => pure (f x)).run