Array

Represents an array (specifically, a Java array when targeting the JVM platform). Array instances can be created using the arrayOf, arrayOfNulls and emptyArray standard library functions. See Kotlin language documentation for more information on arrays.

Since Kotlin

1.0

Constructors

Array

constructor(size: Int, init: (Int) -> T)

Creates a new array with the specified size, where each element is calculated by calling the specified init function.

Properties

indices

val <T> Array<out T>.indices: IntRange

Returns the range of valid indices for the array.

Since Kotlin 1.0

lastIndex

val <T> Array<out T>.lastIndex: Int

Returns the last valid index for the array.

Since Kotlin 1.0

size

val size: Int

Returns the number of elements in the array.

Since Kotlin 1.0

Functions

all

inline fun <T> Array<out T>.all(predicate: (T) -> Boolean): Boolean

Returns true if all elements match the given predicate.

Since Kotlin 1.0

any

fun <T> Array<out T>.any(): Boolean

Returns true if array has at least one element.

Since Kotlin 1.0

inline fun <T> Array<out T>.any(predicate: (T) -> Boolean): Boolean

Returns true if at least one element matches the given predicate.

Since Kotlin 1.0

asIterable

fun <T> Array<out T>.asIterable(): Iterable<T>

Creates an Iterable instance that wraps the original array returning its elements when being iterated.

Since Kotlin 1.0

asList

expect fun <T> Array<out T>.asList(): List<T>

Returns a List that wraps the original array.

Since Kotlin 1.0

actual fun <T> Array<out T>.asList(): List<T>

Returns a List that wraps the original array.

Since Kotlin 1.1

actual fun <T> Array<out T>.asList(): List<T>

Returns a List that wraps the original array.

Since Kotlin 1.0

asSequence

fun <T> Array<out T>.asSequence(): Sequence<T>

Creates a Sequence instance that wraps the original array returning its elements when being iterated.

Since Kotlin 1.0

associate

inline fun <T, K, V> Array<out T>.associate(transform: (T) -> Pair<K, V>): Map<K, V>

Returns a Map containing key-value pairs provided by transform function applied to elements of the given array.

Since Kotlin 1.0

associateBy

inline fun <T, K> Array<out T>.associateBy(keySelector: (T) -> K): Map<K, T>

Returns a Map containing the elements from the given array indexed by the key returned from keySelector function applied to each element.

Since Kotlin 1.0

inline fun <T, K, V> Array<out T>.associateBy(keySelector: (T) -> K, valueTransform: (T) -> V): Map<K, V>

Returns a Map containing the values provided by valueTransform and indexed by keySelector functions applied to elements of the given array.

Since Kotlin 1.0

associateByTo

inline fun <T, K, M : MutableMap<in K, in T>> Array<out T>.associateByTo(destination: M, keySelector: (T) -> K): M

Populates and returns the destination mutable map with key-value pairs, where key is provided by the keySelector function applied to each element of the given array and value is the element itself.

Since Kotlin 1.0

inline fun <T, K, V, M : MutableMap<in K, in V>> Array<out T>.associateByTo(destination: M, keySelector: (T) -> K, valueTransform: (T) -> V): M

Populates and returns the destination mutable map with key-value pairs, where key is provided by the keySelector function and and value is provided by the valueTransform function applied to elements of the given array.

Since Kotlin 1.0

associateTo

inline fun <T, K, V, M : MutableMap<in K, in V>> Array<out T>.associateTo(destination: M, transform: (T) -> Pair<K, V>): M

Populates and returns the destination mutable map with key-value pairs provided by transform function applied to each element of the given array.

Since Kotlin 1.0

average

@JvmName(name = "averageOfByte")

fun Array<out Byte>.average(): Double

@JvmName(name = "averageOfDouble")

fun Array<out Double>.average(): Double

@JvmName(name = "averageOfFloat")

fun Array<out Float>.average(): Double

@JvmName(name = "averageOfInt")

fun Array<out Int>.average(): Double

@JvmName(name = "averageOfLong")

fun Array<out Long>.average(): Double

@JvmName(name = "averageOfShort")

fun Array<out Short>.average(): Double

Returns an average value of elements in the array.

Since Kotlin 1.0

binarySearch

fun <T> Array<out T>.binarySearch(element: T, fromIndex: Int = 0, toIndex: Int = size): Int

Searches the array or the range of the array for the provided element using the binary search algorithm. The array is expected to be sorted, otherwise the result is undefined.

Since Kotlin 1.0

fun <T> Array<out T>.binarySearch(element: T, comparator: Comparator<in T>, fromIndex: Int = 0, toIndex: Int = size): Int

Searches the array or the range of the array for the provided element using the binary search algorithm. The array is expected to be sorted according to the specified comparator, otherwise the result is undefined.

Since Kotlin 1.0

component1

inline operator fun <T> Array<out T>.component1(): T

Returns 1st element from the array.

Since Kotlin 1.0

component2

inline operator fun <T> Array<out T>.component2(): T

Returns 2nd element from the array.

Since Kotlin 1.0

component3

inline operator fun <T> Array<out T>.component3(): T

Returns 3rd element from the array.

Since Kotlin 1.0

component4

inline operator fun <T> Array<out T>.component4(): T

Returns 4th element from the array.

Since Kotlin 1.0

component5

inline operator fun <T> Array<out T>.component5(): T

Returns 5th element from the array.

Since Kotlin 1.0

contains

operator fun <T> Array<out T>.contains(element: T): Boolean

Returns true if element is found in the array.

Since Kotlin 1.0

contentDeepEquals

expect infix fun <T> Array<out T>.contentDeepEquals(other: Array<out T>): Boolean

Returns true if the two specified arrays are deeply equal to one another, i.e. contain the same number of the same elements in the same order.

Since Kotlin 1.1

actual infix fun <T> Array<out T>.contentDeepEquals(other: Array<out T>): Boolean

Returns true if the two specified arrays are deeply equal to one another, i.e. contain the same number of the same elements in the same order.

Since Kotlin 1.1

@JvmName(name = "contentDeepEqualsInline")

actual infix inline fun <T> Array<out T>.contentDeepEquals(other: Array<out T>): Boolean

Returns true if the two specified arrays are deeply equal to one another, i.e. contain the same number of the same elements in the same order.

Since Kotlin 1.1

contentDeepHashCode

expect fun <T> Array<out T>.contentDeepHashCode(): Int

Returns a hash code based on the contents of this array as if it is List. Nested arrays are treated as lists too.

Since Kotlin 1.1

actual fun <T> Array<out T>.contentDeepHashCode(): Int

Returns a hash code based on the contents of this array as if it is List. Nested arrays are treated as lists too.

Since Kotlin 1.1

@JvmName(name = "contentDeepHashCodeInline")

actual inline fun <T> Array<out T>.contentDeepHashCode(): Int

Returns a hash code based on the contents of this array as if it is List. Nested arrays are treated as lists too.

Since Kotlin 1.1

contentDeepToString

expect fun <T> Array<out T>.contentDeepToString(): String

Returns a string representation of the contents of this array as if it is a List. Nested arrays are treated as lists too.

Since Kotlin 1.1

actual fun <T> Array<out T>.contentDeepToString(): String

Returns a string representation of the contents of this array as if it is a List. Nested arrays are treated as lists too.

Since Kotlin 1.1

@JvmName(name = "contentDeepToStringInline")

actual inline fun <T> Array<out T>.contentDeepToString(): String

Returns a string representation of the contents of this array as if it is a List. Nested arrays are treated as lists too.

Since Kotlin 1.1

contentEquals

expect infix fun <T> Array<out T>.~~contentEquals~~(other: Array<out T>): Boolean

Returns true if the two specified arrays are structurally equal to one another, i.e. contain the same number of the same elements in the same order.

Since Kotlin 1.1

actual infix fun <T> Array<out T>.~~contentEquals~~(other: Array<out T>): Boolean

Returns true if the two specified arrays are structurally equal to one another, i.e. contain the same number of the same elements in the same order.

Since Kotlin 1.1

actual infix inline fun <T> Array<out T>.~~contentEquals~~(other: Array<out T>): Boolean

Returns true if the two specified arrays are structurally equal to one another, i.e. contain the same number of the same elements in the same order.

Since Kotlin 1.1

contentHashCode

expect fun <T> Array<out T>.~~contentHashCode~~(): Int

Returns a hash code based on the contents of this array as if it is List.

Since Kotlin 1.1

actual fun <T> Array<out T>.~~contentHashCode~~(): Int

Returns a hash code based on the contents of this array as if it is List.

Since Kotlin 1.1

actual inline fun <T> Array<out T>.~~contentHashCode~~(): Int

Returns a hash code based on the contents of this array as if it is List.

Since Kotlin 1.1

contentToString

expect fun <T> Array<out T>.~~contentToString~~(): String

Returns a string representation of the contents of the specified array as if it is List.

Since Kotlin 1.1

actual fun <T> Array<out T>.~~contentToString~~(): String

Returns a string representation of the contents of the specified array as if it is List.

Since Kotlin 1.1

actual inline fun <T> Array<out T>.~~contentToString~~(): String

Returns a string representation of the contents of the specified array as if it is List.

Since Kotlin 1.1

copyOf

expect fun <T> Array<T>.copyOf(): Array<T>

Returns new array which is a copy of the original array.

Since Kotlin 1.0

expect fun <T> Array<T>.copyOf(newSize: Int): Array<T?>

Returns new array which is a copy of the original array, resized to the given newSize. The copy is either truncated or padded at the end with null values if necessary.

Since Kotlin 1.0

actual inline fun <T> Array<T>.copyOf(): Array<T>

Returns new array which is a copy of the original array.

Since Kotlin 1.1

actual fun <T> Array<T>.copyOf(newSize: Int): Array<T?>

Returns new array which is a copy of the original array, resized to the given newSize. The copy is either truncated or padded at the end with null values if necessary.

Since Kotlin 1.1

actual inline fun <T> Array<T>.copyOf(): Array<T>

Returns new array which is a copy of the original array.

Since Kotlin 1.0

actual inline fun <T> Array<T>.copyOf(newSize: Int): Array<T?>

Returns new array which is a copy of the original array, resized to the given newSize. The copy is either truncated or padded at the end with null values if necessary.

Since Kotlin 1.0

copyOfRange

expect fun <T> Array<T>.copyOfRange(fromIndex: Int, toIndex: Int): Array<T>

Returns a new array which is a copy of the specified range of the original array.

Since Kotlin 1.0

actual fun <T> Array<T>.copyOfRange(fromIndex: Int, toIndex: Int): Array<T>

Returns a new array which is a copy of the specified range of the original array.

Since Kotlin 1.1

@JvmName(name = "copyOfRangeInline")

actual inline fun <T> Array<T>.copyOfRange(fromIndex: Int, toIndex: Int): Array<T>

Returns a new array which is a copy of the specified range of the original array.

Since Kotlin 1.0

count

inline fun <T> Array<out T>.count(): Int

Returns the number of elements in this array.

Since Kotlin 1.0

inline fun <T> Array<out T>.count(predicate: (T) -> Boolean): Int

Returns the number of elements matching the given predicate.

Since Kotlin 1.0

distinct

fun <T> Array<out T>.distinct(): List<T>

Returns a list containing only distinct elements from the given array.

Since Kotlin 1.0

distinctBy

inline fun <T, K> Array<out T>.distinctBy(selector: (T) -> K): List<T>

Returns a list containing only elements from the given array having distinct keys returned by the given selector function.

Since Kotlin 1.0

drop

fun <T> Array<out T>.drop(n: Int): List<T>

Returns a list containing all elements except first n elements.

Since Kotlin 1.0

dropLast

fun <T> Array<out T>.dropLast(n: Int): List<T>

Returns a list containing all elements except last n elements.

Since Kotlin 1.0

dropLastWhile

inline fun <T> Array<out T>.dropLastWhile(predicate: (T) -> Boolean): List<T>

Returns a list containing all elements except last elements that satisfy the given predicate.

Since Kotlin 1.0

dropWhile

inline fun <T> Array<out T>.dropWhile(predicate: (T) -> Boolean): List<T>

Returns a list containing all elements except first elements that satisfy the given predicate.

Since Kotlin 1.0

elementAt

expect fun <T> Array<out T>.elementAt(index: Int): T

Returns an element at the given index or throws an IndexOutOfBoundsException if the index is out of bounds of this array.

Since Kotlin 1.0

actual fun <T> Array<out T>.elementAt(index: Int): T

Returns an element at the given index or throws an IndexOutOfBoundsException if the index is out of bounds of this array.

Since Kotlin 1.1

actual inline fun <T> Array<out T>.elementAt(index: Int): T

Returns an element at the given index or throws an IndexOutOfBoundsException if the index is out of bounds of this array.

Since Kotlin 1.0

elementAtOrElse

inline fun <T> Array<out T>.elementAtOrElse(index: Int, defaultValue: (Int) -> T): T

Returns an element at the given index or the result of calling the defaultValue function if the index is out of bounds of this array.

Since Kotlin 1.0

elementAtOrNull

inline fun <T> Array<out T>.elementAtOrNull(index: Int): T?

Returns an element at the given index or null if the index is out of bounds of this array.

Since Kotlin 1.0

fill

actual fun <T> Array<T>.fill(element: T, fromIndex: Int = 0, toIndex: Int = size)

Fills this array or its subrange with the specified element value.

Since Kotlin 1.0

filter

inline fun <T> Array<out T>.filter(predicate: (T) -> Boolean): List<T>

Returns a list containing only elements matching the given predicate.

Since Kotlin 1.0

filterIndexed

inline fun <T> Array<out T>.filterIndexed(predicate: (index: Int, T) -> Boolean): List<T>

Returns a list containing only elements matching the given predicate.

Since Kotlin 1.0

filterIndexedTo

inline fun <T, C : MutableCollection<in T>> Array<out T>.filterIndexedTo(destination: C, predicate: (index: Int, T) -> Boolean): C

Appends all elements matching the given predicate to the given destination.

Since Kotlin 1.0

filterIsInstance

inline fun <R> Array<*>.filterIsInstance(): List<R>

Returns a list containing all elements that are instances of specified type parameter R.

Since Kotlin 1.0

fun <R> Array<*>.filterIsInstance(klass: Class<R>): List<R>

Returns a list containing all elements that are instances of specified class.

Since Kotlin 1.0

filterIsInstanceTo

inline fun <R, C : MutableCollection<in R>> Array<*>.filterIsInstanceTo(destination: C): C

Appends all elements that are instances of specified type parameter R to the given destination.

Since Kotlin 1.0

fun <C : MutableCollection<in R>, R> Array<*>.filterIsInstanceTo(destination: C, klass: Class<R>): C

Appends all elements that are instances of specified class to the given destination.

Since Kotlin 1.0

filterNot

inline fun <T> Array<out T>.filterNot(predicate: (T) -> Boolean): List<T>

Returns a list containing all elements not matching the given predicate.

Since Kotlin 1.0

filterNotNull

fun <T : Any> Array<out T?>.filterNotNull(): List<T>

Returns a list containing all elements that are not null.

Since Kotlin 1.0

filterNotNullTo

fun <C : MutableCollection<in T>, T : Any> Array<out T?>.filterNotNullTo(destination: C): C

Appends all elements that are not null to the given destination.

Since Kotlin 1.0

filterNotTo

inline fun <T, C : MutableCollection<in T>> Array<out T>.filterNotTo(destination: C, predicate: (T) -> Boolean): C

Appends all elements not matching the given predicate to the given destination.

Since Kotlin 1.0

filterTo

inline fun <T, C : MutableCollection<in T>> Array<out T>.filterTo(destination: C, predicate: (T) -> Boolean): C

Appends all elements matching the given predicate to the given destination.

Since Kotlin 1.0

find

inline fun <T> Array<out T>.find(predicate: (T) -> Boolean): T?

Returns the first element matching the given predicate, or null if no such element was found.

Since Kotlin 1.0

findLast

inline fun <T> Array<out T>.findLast(predicate: (T) -> Boolean): T?

Returns the last element matching the given predicate, or null if no such element was found.

Since Kotlin 1.0

first

fun <T> Array<out T>.first(): T

Returns first element.

Since Kotlin 1.0

inline fun <T> Array<out T>.first(predicate: (T) -> Boolean): T

Returns the first element matching the given predicate.

Since Kotlin 1.0

firstOrNull

fun <T> Array<out T>.firstOrNull(): T?

Returns the first element, or null if the array is empty.

Since Kotlin 1.0

inline fun <T> Array<out T>.firstOrNull(predicate: (T) -> Boolean): T?

Returns the first element matching the given predicate, or null if element was not found.

Since Kotlin 1.0

flatMap

inline fun <T, R> Array<out T>.flatMap(transform: (T) -> Iterable<R>): List<R>

Returns a single list of all elements yielded from results of transform function being invoked on each element of original array.

Since Kotlin 1.0

flatMapTo

inline fun <T, R, C : MutableCollection<in R>> Array<out T>.flatMapTo(destination: C, transform: (T) -> Iterable<R>): C

Appends all elements yielded from results of transform function being invoked on each element of original array, to the given destination.

Since Kotlin 1.0

flatten

fun <T> Array<out Array<out T>>.flatten(): List<T>

Returns a single list of all elements from all arrays in the given array.

Since Kotlin 1.0

fold

inline fun <T, R> Array<out T>.fold(initial: R, operation: (acc: R, T) -> R): R

Accumulates value starting with initial value and applying operation from left to right to current accumulator value and each element.

Since Kotlin 1.0

foldIndexed

inline fun <T, R> Array<out T>.foldIndexed(initial: R, operation: (index: Int, acc: R, T) -> R): R

Accumulates value starting with initial value and applying operation from left to right to current accumulator value and each element with its index in the original array.

Since Kotlin 1.0

foldRight

inline fun <T, R> Array<out T>.foldRight(initial: R, operation: (T, acc: R) -> R): R

Accumulates value starting with initial value and applying operation from right to left to each element and current accumulator value.

Since Kotlin 1.0

foldRightIndexed

inline fun <T, R> Array<out T>.foldRightIndexed(initial: R, operation: (index: Int, T, acc: R) -> R): R

Accumulates value starting with initial value and applying operation from right to left to each element with its index in the original array and current accumulator value.

Since Kotlin 1.0

forEach

inline fun <T> Array<out T>.forEach(action: (T) -> Unit)

Performs the given action on each element.

Since Kotlin 1.0

forEachIndexed

inline fun <T> Array<out T>.forEachIndexed(action: (index: Int, T) -> Unit)

Performs the given action on each element, providing sequential index with the element.

Since Kotlin 1.0

get

operator fun get(index: Int): T

Returns the array element at the specified index. This method can be called using the index operator.

Since Kotlin 1.0

getOrElse

inline fun <T> Array<out T>.getOrElse(index: Int, defaultValue: (Int) -> T): T

Returns an element at the given index or the result of calling the defaultValue function if the index is out of bounds of this array.

Since Kotlin 1.0

getOrNull

fun <T> Array<out T>.getOrNull(index: Int): T?

Returns an element at the given index or null if the index is out of bounds of this array.

Since Kotlin 1.0

groupBy

inline fun <T, K> Array<out T>.groupBy(keySelector: (T) -> K): Map<K, List<T>>

Groups elements of the original array by the key returned by the given keySelector function applied to each element and returns a map where each group key is associated with a list of corresponding elements.

Since Kotlin 1.0

inline fun <T, K, V> Array<out T>.groupBy(keySelector: (T) -> K, valueTransform: (T) -> V): Map<K, List<V>>

Groups values returned by the valueTransform function applied to each element of the original array by the key returned by the given keySelector function applied to the element and returns a map where each group key is associated with a list of corresponding values.

Since Kotlin 1.0

groupByTo

inline fun <T, K, M : MutableMap<in K, MutableList<T>>> Array<out T>.groupByTo(destination: M, keySelector: (T) -> K): M

Groups elements of the original array by the key returned by the given keySelector function applied to each element and puts to the destination map each group key associated with a list of corresponding elements.

Since Kotlin 1.0

inline fun <T, K, V, M : MutableMap<in K, MutableList<V>>> Array<out T>.groupByTo(destination: M, keySelector: (T) -> K, valueTransform: (T) -> V): M

Groups values returned by the valueTransform function applied to each element of the original array by the key returned by the given keySelector function applied to the element and puts to the destination map each group key associated with a list of corresponding values.

Since Kotlin 1.0

groupingBy

inline fun <T, K> Array<out T>.groupingBy(crossinline keySelector: (T) -> K): Grouping<T, K>

Creates a Grouping source from an array to be used later with one of group-and-fold operations using the specified keySelector function to extract a key from each element.

Since Kotlin 1.1

indexOf

fun <T> Array<out T>.indexOf(element: T): Int

Returns first index of element, or -1 if the array does not contain element.

Since Kotlin 1.0

indexOfFirst

inline fun <T> Array<out T>.indexOfFirst(predicate: (T) -> Boolean): Int

Returns index of the first element matching the given predicate, or -1 if the array does not contain such element.

Since Kotlin 1.0

indexOfLast

inline fun <T> Array<out T>.indexOfLast(predicate: (T) -> Boolean): Int

Returns index of the last element matching the given predicate, or -1 if the array does not contain such element.

Since Kotlin 1.0

intersect

infix fun <T> Array<out T>.intersect(other: Iterable<T>): Set<T>

Returns a set containing all elements that are contained by both this array and the specified collection.

Since Kotlin 1.0

isArrayOf

fun <T : Any> Array<*>.isArrayOf(): Boolean

Checks if array can contain element of type T.

Since Kotlin 1.0

isEmpty

inline fun <T> Array<out T>.isEmpty(): Boolean

Returns true if the array is empty.

Since Kotlin 1.0

isNotEmpty

inline fun <T> Array<out T>.isNotEmpty(): Boolean

Returns true if the array is not empty.

Since Kotlin 1.0

iterator

operator fun iterator(): Iterator<T>

Creates an Iterator for iterating over the elements of the array.

Since Kotlin 1.0

joinTo

fun <T, A : Appendable> Array<out T>.joinTo(buffer: A, separator: CharSequence = ", ", prefix: CharSequence = "", postfix: CharSequence = "", limit: Int = -1, truncated: CharSequence = "...", transform: (T) -> CharSequence? = null): A

Appends the string from all the elements separated using separator and using the given prefix and postfix if supplied.

Since Kotlin 1.0

joinToString

fun <T> Array<out T>.joinToString(separator: CharSequence = ", ", prefix: CharSequence = "", postfix: CharSequence = "", limit: Int = -1, truncated: CharSequence = "...", transform: (T) -> CharSequence? = null): String

Creates a string from all the elements separated using separator and using the given prefix and postfix if supplied.

Since Kotlin 1.0

last

fun <T> Array<out T>.last(): T

Returns the last element.

Since Kotlin 1.0

inline fun <T> Array<out T>.last(predicate: (T) -> Boolean): T

Returns the last element matching the given predicate.

Since Kotlin 1.0

lastIndexOf

fun <T> Array<out T>.lastIndexOf(element: T): Int

Returns last index of element, or -1 if the array does not contain element.

Since Kotlin 1.0

lastOrNull

fun <T> Array<out T>.lastOrNull(): T?

Returns the last element, or null if the array is empty.

Since Kotlin 1.0

inline fun <T> Array<out T>.lastOrNull(predicate: (T) -> Boolean): T?

Returns the last element matching the given predicate, or null if no such element was found.

Since Kotlin 1.0

map

inline fun <T, R> Array<out T>.map(transform: (T) -> R): List<R>

Returns a list containing the results of applying the given transform function to each element in the original array.

Since Kotlin 1.0

mapIndexed

inline fun <T, R> Array<out T>.mapIndexed(transform: (index: Int, T) -> R): List<R>

Returns a list containing the results of applying the given transform function to each element and its index in the original array.

Since Kotlin 1.0

mapIndexedNotNull

inline fun <T, R : Any> Array<out T>.mapIndexedNotNull(transform: (index: Int, T) -> R?): List<R>

Returns a list containing only the non-null results of applying the given transform function to each element and its index in the original array.

Since Kotlin 1.0

mapIndexedNotNullTo

inline fun <T, R : Any, C : MutableCollection<in R>> Array<out T>.mapIndexedNotNullTo(destination: C, transform: (index: Int, T) -> R?): C

Applies the given transform function to each element and its index in the original array and appends only the non-null results to the given destination.

Since Kotlin 1.0

mapIndexedTo

inline fun <T, R, C : MutableCollection<in R>> Array<out T>.mapIndexedTo(destination: C, transform: (index: Int, T) -> R): C

Applies the given transform function to each element and its index in the original array and appends the results to the given destination.

Since Kotlin 1.0

mapNotNull

inline fun <T, R : Any> Array<out T>.mapNotNull(transform: (T) -> R?): List<R>

Returns a list containing only the non-null results of applying the given transform function to each element in the original array.

Since Kotlin 1.0

mapNotNullTo

inline fun <T, R : Any, C : MutableCollection<in R>> Array<out T>.mapNotNullTo(destination: C, transform: (T) -> R?): C

Applies the given transform function to each element in the original array and appends only the non-null results to the given destination.

Since Kotlin 1.0

mapTo

inline fun <T, R, C : MutableCollection<in R>> Array<out T>.mapTo(destination: C, transform: (T) -> R): C

Applies the given transform function to each element of the original array and appends the results to the given destination.

Since Kotlin 1.0

max

fun <T : Comparable<T>> Array<out T>.~~max~~(): T?

Since Kotlin 1.0

fun Array<out Double>.~~max~~(): Double?

fun Array<out Float>.~~max~~(): Float?

Since Kotlin 1.1

maxBy

inline fun <T, R : Comparable<R>> Array<out T>.~~maxBy~~(selector: (T) -> R): T?

Since Kotlin 1.0

maxWith

fun <T> Array<out T>.~~maxWith~~(comparator: Comparator<in T>): T?

Since Kotlin 1.0

min

fun <T : Comparable<T>> Array<out T>.~~min~~(): T?

Since Kotlin 1.0

fun Array<out Double>.~~min~~(): Double?

fun Array<out Float>.~~min~~(): Float?

Since Kotlin 1.1

minBy

inline fun <T, R : Comparable<R>> Array<out T>.~~minBy~~(selector: (T) -> R): T?

Since Kotlin 1.0

minWith

fun <T> Array<out T>.~~minWith~~(comparator: Comparator<in T>): T?

Since Kotlin 1.0

none

fun <T> Array<out T>.none(): Boolean

Returns true if the array has no elements.

Since Kotlin 1.0

inline fun <T> Array<out T>.none(predicate: (T) -> Boolean): Boolean

Returns true if no elements match the given predicate.

Since Kotlin 1.0

orEmpty

expect inline fun <T> Array<out T>?.orEmpty(): Array<out T>

Returns the array if it's not null, or an empty array otherwise.

Since Kotlin 1.0

actual inline fun <T> Array<out T>?.orEmpty(): Array<out T>

Returns the array if it's not null, or an empty array otherwise.

Since Kotlin 1.1

actual inline fun <T> Array<out T>?.orEmpty(): Array<out T>

Returns the array if it's not null, or an empty array otherwise.

Since Kotlin 1.0

partition

inline fun <T> Array<out T>.partition(predicate: (T) -> Boolean): Pair<List<T>, List<T>>

Splits the original array into pair of lists, where first list contains elements for which predicate yielded true, while second list contains elements for which predicate yielded false.

Since Kotlin 1.0

plus

expect operator fun <T> Array<T>.plus(element: T): Array<T>

Returns an array containing all elements of the original array and then the given element.

Since Kotlin 1.0

expect operator fun <T> Array<T>.plus(elements: Array<out T>): Array<T>

Returns an array containing all elements of the original array and then all elements of the given elements array.

Since Kotlin 1.0

expect operator fun <T> Array<T>.plus(elements: Collection<T>): Array<T>

Returns an array containing all elements of the original array and then all elements of the given elements collection.

Since Kotlin 1.0

actual inline operator fun <T> Array<T>.plus(element: T): Array<T>

Returns an array containing all elements of the original array and then the given element.

Since Kotlin 1.1

actual inline operator fun <T> Array<T>.plus(elements: Array<out T>): Array<T>

Returns an array containing all elements of the original array and then all elements of the given elements array.

Since Kotlin 1.1

actual operator fun <T> Array<T>.plus(elements: Collection<T>): Array<T>

Returns an array containing all elements of the original array and then all elements of the given elements collection.

Since Kotlin 1.1

actual operator fun <T> Array<T>.plus(element: T): Array<T>

Returns an array containing all elements of the original array and then the given element.

Since Kotlin 1.0

actual operator fun <T> Array<T>.plus(elements: Array<out T>): Array<T>

Returns an array containing all elements of the original array and then all elements of the given elements array.

Since Kotlin 1.0

actual operator fun <T> Array<T>.plus(elements: Collection<T>): Array<T>

Returns an array containing all elements of the original array and then all elements of the given elements collection.

Since Kotlin 1.0

plusElement

expect fun <T> Array<T>.plusElement(element: T): Array<T>

Returns an array containing all elements of the original array and then the given element.

Since Kotlin 1.0

actual inline fun <T> Array<T>.plusElement(element: T): Array<T>

Returns an array containing all elements of the original array and then the given element.

Since Kotlin 1.1

actual inline fun <T> Array<T>.plusElement(element: T): Array<T>

Returns an array containing all elements of the original array and then the given element.

Since Kotlin 1.0

reduce

inline fun <S, T : S> Array<out T>.reduce(operation: (acc: S, T) -> S): S

Accumulates value starting with the first element and applying operation from left to right to current accumulator value and each element.

Since Kotlin 1.0

reduceIndexed

inline fun <S, T : S> Array<out T>.reduceIndexed(operation: (index: Int, acc: S, T) -> S): S

Accumulates value starting with the first element and applying operation from left to right to current accumulator value and each element with its index in the original array.

Since Kotlin 1.0

reduceRight

inline fun <S, T : S> Array<out T>.reduceRight(operation: (T, acc: S) -> S): S

Accumulates value starting with the last element and applying operation from right to left to each element and current accumulator value.

Since Kotlin 1.0

reduceRightIndexed

inline fun <S, T : S> Array<out T>.reduceRightIndexed(operation: (index: Int, T, acc: S) -> S): S

Accumulates value starting with the last element and applying operation from right to left to each element with its index in the original array and current accumulator value.

Since Kotlin 1.0

requireNoNulls

fun <T : Any> Array<T?>.requireNoNulls(): Array<T>

Returns an original collection containing all the non-null elements, throwing an IllegalArgumentException if there are any null elements.

Since Kotlin 1.0

reverse

fun <T> Array<T>.reverse()

Reverses elements in the array in-place.

Since Kotlin 1.0

reversed

fun <T> Array<out T>.reversed(): List<T>

Returns a list with elements in reversed order.

Since Kotlin 1.0

reversedArray

fun <T> Array<T>.reversedArray(): Array<T>

Returns an array with elements of this array in reversed order.

Since Kotlin 1.0

set

operator fun set(index: Int, value: T)

Sets the array element at the specified index to the specified value. This method can be called using the index operator.

Since Kotlin 1.0

single

fun <T> Array<out T>.single(): T

Returns the single element, or throws an exception if the array is empty or has more than one element.

Since Kotlin 1.0

inline fun <T> Array<out T>.single(predicate: (T) -> Boolean): T

Returns the single element matching the given predicate, or throws exception if there is no or more than one matching element.

Since Kotlin 1.0

singleOrNull

fun <T> Array<out T>.singleOrNull(): T?

Returns single element, or null if the array is empty or has more than one element.

Since Kotlin 1.0

inline fun <T> Array<out T>.singleOrNull(predicate: (T) -> Boolean): T?

Returns the single element matching the given predicate, or null if element was not found or more than one element was found.

Since Kotlin 1.0

slice

fun <T> Array<out T>.slice(indices: Iterable<Int>): List<T>

Returns a list containing elements at specified indices.

Since Kotlin 1.0

fun <T> Array<out T>.slice(indices: IntRange): List<T>

Returns a list containing elements at indices in the specified indices range.

Since Kotlin 1.0

sliceArray

fun <T> Array<T>.sliceArray(indices: Collection<Int>): Array<T>

Returns an array containing elements of this array at specified indices.

Since Kotlin 1.0

fun <T> Array<T>.sliceArray(indices: IntRange): Array<T>

Returns an array containing elements at indices in the specified indices range.

Since Kotlin 1.0

sort

expect fun <T : Comparable<T>> Array<out T>.sort()

Sorts the array in-place according to the natural order of its elements.

Since Kotlin 1.0

actual fun <T : Comparable<T>> Array<out T>.sort()

Sorts the array in-place according to the natural order of its elements.

Since Kotlin 1.1

fun <T> Array<out T>.~~sort~~(comparison: (a: T, b: T) -> Int)

Sorts the array in-place according to the order specified by the given comparison function.

Since Kotlin 1.1

fun <T> Array<out T>.sort()

actual inline fun <T : Comparable<T>> Array<out T>.sort()

Sorts the array in-place according to the natural order of its elements.

Since Kotlin 1.0

fun <T> Array<out T>.sort(fromIndex: Int = 0, toIndex: Int = size)

Sorts a range in the array in-place.

Since Kotlin 1.0

sortBy

inline fun <T, R : Comparable<R>> Array<out T>.sortBy(crossinline selector: (T) -> R?)

Sorts elements in the array in-place according to natural sort order of the value returned by specified selector function.

Since Kotlin 1.0

sortByDescending

inline fun <T, R : Comparable<R>> Array<out T>.sortByDescending(crossinline selector: (T) -> R?)

Sorts elements in the array in-place descending according to natural sort order of the value returned by specified selector function.

Since Kotlin 1.0

sortDescending

fun <T : Comparable<T>> Array<out T>.sortDescending()

Sorts elements in the array in-place descending according to their natural sort order.

Since Kotlin 1.0

sorted

fun <T : Comparable<T>> Array<out T>.sorted(): List<T>

Returns a list of all elements sorted according to their natural sort order.

Since Kotlin 1.0

sortedArray

fun <T : Comparable<T>> Array<T>.sortedArray(): Array<T>

Returns an array with all elements of this array sorted according to their natural sort order.

Since Kotlin 1.0

sortedArrayDescending

fun <T : Comparable<T>> Array<T>.sortedArrayDescending(): Array<T>

Returns an array with all elements of this array sorted descending according to their natural sort order.

Since Kotlin 1.0

sortedArrayWith

fun <T> Array<out T>.sortedArrayWith(comparator: Comparator<in T>): Array<out T>

Returns an array with all elements of this array sorted according the specified comparator.

Since Kotlin 1.0

sortedBy

inline fun <T, R : Comparable<R>> Array<out T>.sortedBy(crossinline selector: (T) -> R?): List<T>

Returns a list of all elements sorted according to natural sort order of the value returned by specified selector function.

Since Kotlin 1.0

sortedByDescending

inline fun <T, R : Comparable<R>> Array<out T>.sortedByDescending(crossinline selector: (T) -> R?): List<T>

Returns a list of all elements sorted descending according to natural sort order of the value returned by specified selector function.

Since Kotlin 1.0

sortedDescending

fun <T : Comparable<T>> Array<out T>.sortedDescending(): List<T>

Returns a list of all elements sorted descending according to their natural sort order.

Since Kotlin 1.0

sortedWith

fun <T> Array<out T>.sortedWith(comparator: Comparator<in T>): List<T>

Returns a list of all elements sorted according to the specified comparator.

Since Kotlin 1.0

sortWith

expect fun <T> Array<out T>.sortWith(comparator: Comparator<in T>)

Sorts the array in-place according to the order specified by the given comparator.

Since Kotlin 1.0

expect fun <T> Array<out T>.sortWith(comparator: Comparator<in T>, fromIndex: Int = 0, toIndex: Int = size)

Sorts a range in the array in-place with the given comparator.

Since Kotlin 1.0

actual fun <T> Array<out T>.sortWith(comparator: Comparator<in T>)

Sorts the array in-place according to the order specified by the given comparator.

Since Kotlin 1.1

actual fun <T> Array<out T>.sortWith(comparator: Comparator<in T>)

Sorts the array in-place according to the order specified by the given comparator.

Since Kotlin 1.0

actual fun <T> Array<out T>.sortWith(comparator: Comparator<in T>, fromIndex: Int = 0, toIndex: Int = size)

Sorts a range in the array in-place with the given comparator.

Since Kotlin 1.0

subtract

infix fun <T> Array<out T>.subtract(other: Iterable<T>): Set<T>

Returns a set containing all elements that are contained by this array and not contained by the specified collection.

Since Kotlin 1.0

sum

@JvmName(name = "sumOfByte")

fun Array<out Byte>.sum(): Int

@JvmName(name = "sumOfDouble")

fun Array<out Double>.sum(): Double

@JvmName(name = "sumOfFloat")

fun Array<out Float>.sum(): Float

@JvmName(name = "sumOfInt")

fun Array<out Int>.sum(): Int

@JvmName(name = "sumOfLong")

fun Array<out Long>.sum(): Long

@JvmName(name = "sumOfShort")

fun Array<out Short>.sum(): Int

Returns the sum of all elements in the array.

Since Kotlin 1.0

sumBy

inline fun <T> Array<out T>.~~sumBy~~(selector: (T) -> Int): Int

Returns the sum of all values produced by selector function applied to each element in the array.

Since Kotlin 1.0

sumByDouble

inline fun <T> Array<out T>.~~sumByDouble~~(selector: (T) -> Double): Double

Returns the sum of all values produced by selector function applied to each element in the array.

Since Kotlin 1.0

take

fun <T> Array<out T>.take(n: Int): List<T>

Returns a list containing first n elements.

Since Kotlin 1.0

takeLast

fun <T> Array<out T>.takeLast(n: Int): List<T>

Returns a list containing last n elements.

Since Kotlin 1.0

takeLastWhile

inline fun <T> Array<out T>.takeLastWhile(predicate: (T) -> Boolean): List<T>

Returns a list containing last elements satisfying the given predicate.

Since Kotlin 1.0

takeWhile

inline fun <T> Array<out T>.takeWhile(predicate: (T) -> Boolean): List<T>

Returns a list containing first elements satisfying the given predicate.

Since Kotlin 1.0

toBooleanArray

fun Array<out Boolean>.toBooleanArray(): BooleanArray

Returns an array of Boolean containing all of the elements of this generic array.

Since Kotlin 1.0

toByteArray

fun Array<out Byte>.toByteArray(): ByteArray

Returns an array of Byte containing all of the elements of this generic array.

Since Kotlin 1.0

toCharArray

fun Array<out Char>.toCharArray(): CharArray

Returns an array of Char containing all of the elements of this generic array.

Since Kotlin 1.0

toCollection

fun <T, C : MutableCollection<in T>> Array<out T>.toCollection(destination: C): C

Appends all elements to the given destination collection.

Since Kotlin 1.0

toDoubleArray

fun Array<out Double>.toDoubleArray(): DoubleArray

Returns an array of Double containing all of the elements of this generic array.

Since Kotlin 1.0

toFloatArray

fun Array<out Float>.toFloatArray(): FloatArray

Returns an array of Float containing all of the elements of this generic array.

Since Kotlin 1.0

toHashSet

fun <T> Array<out T>.toHashSet(): HashSet<T>

Returns a new HashSet of all elements.

Since Kotlin 1.0

toIntArray

fun Array<out Int>.toIntArray(): IntArray

Returns an array of Int containing all of the elements of this generic array.

Since Kotlin 1.0

toList

fun <T> Array<out T>.toList(): List<T>

Returns a List containing all elements.

Since Kotlin 1.0

toLongArray

fun Array<out Long>.toLongArray(): LongArray

Returns an array of Long containing all of the elements of this generic array.

Since Kotlin 1.0

toMap

fun <K, V> Array<out Pair<K, V>>.toMap(): Map<K, V>

Returns a new map containing all key-value pairs from the given array of pairs.

Since Kotlin 1.0

fun <K, V, M : MutableMap<in K, in V>> Array<out Pair<K, V>>.toMap(destination: M): M

Populates and returns the destination mutable map with key-value pairs from the given array of pairs.

Since Kotlin 1.0

toMutableList

fun <T> Array<out T>.toMutableList(): MutableList<T>

Returns a new MutableList filled with all elements of this array.

Since Kotlin 1.0

toMutableSet

fun <T> Array<out T>.toMutableSet(): MutableSet<T>

Returns a new MutableSet containing all distinct elements from the given array.

Since Kotlin 1.0

toSet

fun <T> Array<out T>.toSet(): Set<T>

Returns a Set of all elements.

Since Kotlin 1.0

toShortArray

fun Array<out Short>.toShortArray(): ShortArray

Returns an array of Short containing all of the elements of this generic array.

Since Kotlin 1.0

toSortedSet

fun <T : Comparable<T>> Array<out T>.toSortedSet(): SortedSet<T>

fun <T> Array<out T>.toSortedSet(comparator: Comparator<in T>): SortedSet<T>

Returns a new SortedSet of all elements.

Since Kotlin 1.0

union

infix fun <T> Array<out T>.union(other: Iterable<T>): Set<T>

Returns a set containing all distinct elements from both collections.

Since Kotlin 1.0

unzip

fun <T, R> Array<out Pair<T, R>>.unzip(): Pair<List<T>, List<R>>

Returns a pair of lists, where first list is built from the first values of each pair from this array, second list is built from the second values of each pair from this array.

Since Kotlin 1.0

withIndex

fun <T> Array<out T>.withIndex(): Iterable<IndexedValue<T>>

Returns a lazy Iterable that wraps each element of the original array into an IndexedValue containing the index of that element and the element itself.

Since Kotlin 1.0

zip

infix fun <T, R> Array<out T>.zip(other: Array<out R>): List<Pair<T, R>>

Returns a list of pairs built from the elements of this array and the other array with the same index. The returned list has length of the shortest collection.

Since Kotlin 1.0

infix fun <T, R> Array<out T>.zip(other: Iterable<R>): List<Pair<T, R>>

Returns a list of pairs built from the elements of this collection and other array with the same index. The returned list has length of the shortest collection.

Since Kotlin 1.0

inline fun <T, R, V> Array<out T>.zip(other: Array<out R>, transform: (a: T, b: R) -> V): List<V>

Returns a list of values built from the elements of this array and the other array with the same index using the provided transform function applied to each pair of elements. The returned list has length of the shortest collection.

Since Kotlin 1.0

inline fun <T, R, V> Array<out T>.zip(other: Iterable<R>, transform: (a: T, b: R) -> V): List<V>

Returns a list of values built from the elements of this array and the other collection with the same index using the provided transform function applied to each pair of elements. The returned list has length of the shortest collection.

Since Kotlin 1.0

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