String

Common
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Native
1.0

The String class represents character strings. All string literals in Kotlin programs, such as "abc", are implemented as instances of this class.

Constructors

Common
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1.0

<init>

The String class represents character strings. All string literals in Kotlin programs, such as "abc", are implemented as instances of this class.

<init>()

Properties

Common
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1.0

length

Returns the length of this character sequence.

val length: Int

Functions

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1.0

compareTo

Compares this object with the specified object for order. Returns zero if this object is equal to the specified other object, a negative number if it's less than other, or a positive number if it's greater than other.

fun compareTo(other: String): Int
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1.0

equals

Indicates whether some other object is "equal to" this one. Implementations must fulfil the following requirements:

fun equals(other: Any?): Boolean
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1.0

get

Returns the character of this string at the specified index.

fun get(index: Int): Char
JS
Native
1.1

hashCode

Returns a hash code value for the object. The general contract of hashCode is:

fun hashCode(): Int
Common
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1.0

plus

Returns a string obtained by concatenating this string with the string representation of the given other object.

operator fun plus(other: Any?): String
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1.0

subSequence

Returns a new character sequence that is a subsequence of this character sequence, starting at the specified startIndex and ending right before the specified endIndex.

fun subSequence(startIndex: Int, endIndex: Int): CharSequence
Common
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1.0

toString

Returns a string representation of the object.

fun toString(): String

Extension Properties

Native
1.3

cstr

val String.cstr: CValues<ByteVar>
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1.0

indices

Returns the range of valid character indices for this char sequence.

val CharSequence.indices: IntRange
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1.0

lastIndex

Returns the index of the last character in the char sequence or -1 if it is empty.

val CharSequence.lastIndex: Int
Native
1.3

utf16

val String.utf16: CValues<UShortVar>
Native
1.3

utf32

val String.utf32: CValues<IntVar>
Native
1.3

utf8

val String.utf8: CValues<ByteVar>
Native
1.3

wcstr

val String.wcstr: CValues<UShortVar>

Extension Functions

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1.0

all

Returns true if all characters match the given predicate.

fun CharSequence.all(predicate: (Char) -> Boolean): Boolean
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1.0

any

Returns true if char sequence has at least one character.

fun CharSequence.any(): Boolean

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

fun CharSequence.any(predicate: (Char) -> Boolean): Boolean
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1.0

asIterable

Creates an Iterable instance that wraps the original char sequence returning its characters when being iterated.

fun CharSequence.asIterable(): Iterable<Char>
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1.0

asSequence

Creates a Sequence instance that wraps the original char sequence returning its characters when being iterated.

fun CharSequence.asSequence(): Sequence<Char>
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1.0

associate

Returns a Map containing key-value pairs provided by transform function applied to characters of the given char sequence.

fun <K, V> CharSequence.associate(
    transform: (Char) -> Pair<K, V>
): Map<K, V>
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1.0

associateBy

Returns a Map containing the characters from the given char sequence indexed by the key returned from keySelector function applied to each character.

fun <K> CharSequence.associateBy(
    keySelector: (Char) -> K
): Map<K, Char>

Returns a Map containing the values provided by valueTransform and indexed by keySelector functions applied to characters of the given char sequence.

fun <K, V> CharSequence.associateBy(
    keySelector: (Char) -> K,
    valueTransform: (Char) -> V
): Map<K, V>
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1.0

associateByTo

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

fun <K, M : MutableMap<in K, in Char>> CharSequence.associateByTo(
    destination: M,
    keySelector: (Char) -> K
): 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 characters of the given char sequence.

fun <K, V, M : MutableMap<in K, in V>> CharSequence.associateByTo(
    destination: M,
    keySelector: (Char) -> K,
    valueTransform: (Char) -> V
): M
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1.0

associateTo

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

fun <K, V, M : MutableMap<in K, in V>> CharSequence.associateTo(
    destination: M,
    transform: (Char) -> Pair<K, V>
): M
Common
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1.3

associateWith

Returns a Map where keys are characters from the given char sequence and values are produced by the valueSelector function applied to each character.

fun <V> CharSequence.associateWith(
    valueSelector: (Char) -> V
): Map<Char, V>
Common
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1.3

associateWithTo

Populates and returns the destination mutable map with key-value pairs for each character of the given char sequence, where key is the character itself and value is provided by the valueSelector function applied to that key.

fun <V, M : MutableMap<in Char, in V>> CharSequence.associateWithTo(
    destination: M,
    valueSelector: (Char) -> V
): M
JVM
1.0

byteInputStream

Creates a new byte input stream for the string.

fun String.byteInputStream(
    charset: Charset = Charsets.UTF_8
): ByteArrayInputStream
JVM
1.4

capitalize

Returns a copy of this string having its first letter titlecased using the rules of the specified locale, or the original string if it's empty or already starts with a title case letter.

fun String.capitalize(locale: Locale): String
Common
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1.2

chunked

Splits this char sequence into a list of strings each not exceeding the given size.

fun CharSequence.chunked(size: Int): List<String>

Splits this char sequence into several char sequences each not exceeding the given size and applies the given transform function to an each.

fun <R> CharSequence.chunked(
    size: Int,
    transform: (CharSequence) -> R
): List<R>
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1.2

chunkedSequence

Splits this char sequence into a sequence of strings each not exceeding the given size.

fun CharSequence.chunkedSequence(size: Int): Sequence<String>

Splits this char sequence into several char sequences each not exceeding the given size and applies the given transform function to an each.

fun <R> CharSequence.chunkedSequence(
    size: Int,
    transform: (CharSequence) -> R
): Sequence<R>
JVM
1.0

codePointAt

Returns the character (Unicode code point) at the specified index.

fun String.codePointAt(index: Int): Int
JVM
1.0

codePointBefore

Returns the character (Unicode code point) before the specified index.

fun String.codePointBefore(index: Int): Int
JVM
1.0

codePointCount

Returns the number of Unicode code points in the specified text range of this String.

fun String.codePointCount(
    beginIndex: Int,
    endIndex: Int
): Int
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1.0

coerceAtLeast

Ensures that this value is not less than the specified minimumValue.

fun <T : Comparable<T>> T.coerceAtLeast(minimumValue: T): T
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1.0

coerceAtMost

Ensures that this value is not greater than the specified maximumValue.

fun <T : Comparable<T>> T.coerceAtMost(maximumValue: T): T
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1.0

coerceIn

Ensures that this value lies in the specified range minimumValue..maximumValue.

fun <T : Comparable<T>> T.coerceIn(
    minimumValue: T?,
    maximumValue: T?
): T

Ensures that this value lies in the specified range.

fun <T : Comparable<T>> T.coerceIn(
    range: ClosedFloatingPointRange<T>
): T
fun <T : Comparable<T>> T.coerceIn(range: ClosedRange<T>): T
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1.0

commonPrefixWith

Returns the longest string prefix such that this char sequence and other char sequence both start with this prefix, taking care not to split surrogate pairs. If this and other have no common prefix, returns the empty string.

fun CharSequence.commonPrefixWith(
    other: CharSequence,
    ignoreCase: Boolean = false
): String
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1.0

commonSuffixWith

Returns the longest string suffix such that this char sequence and other char sequence both end with this suffix, taking care not to split surrogate pairs. If this and other have no common suffix, returns the empty string.

fun CharSequence.commonSuffixWith(
    other: CharSequence,
    ignoreCase: Boolean = false
): String
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1.6

compareTo

Compares this object with the specified object for order. Returns zero if this object is equal to the specified other object, a negative number if it's less than other, or a positive number if it's greater than other.

infix fun <T> Comparable<T>.compareTo(other: T): Int
JS
1.1

concat

fun String.concat(str: String): String
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1.0

contains

Returns true if this char sequence contains the specified other sequence of characters as a substring.

operator fun CharSequence.contains(
    other: CharSequence,
    ignoreCase: Boolean = false
): Boolean

Returns true if this char sequence contains the specified character char.

operator fun CharSequence.contains(
    char: Char,
    ignoreCase: Boolean = false
): Boolean

Returns true if this char sequence contains at least one match of the specified regular expression regex.

operator fun CharSequence.contains(regex: Regex): Boolean
JVM
1.0

contentEquals

Returns true if this string is equal to the contents of the specified CharSequence, false otherwise.

fun String.contentEquals(charSequence: CharSequence): Boolean

Returns true if this string is equal to the contents of the specified StringBuffer, false otherwise.

fun String.contentEquals(
    stringBuilder: StringBuffer
): Boolean
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1.0

count

Returns the length of this char sequence.

fun CharSequence.count(): Int

Returns the number of characters matching the given predicate.

fun CharSequence.count(predicate: (Char) -> Boolean): Int
JVM
1.4

decapitalize

Returns a copy of this string having its first letter lowercased using the rules of the specified locale, or the original string, if it's empty or already starts with a lower case letter.

fun String.decapitalize(locale: Locale): String
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1.0

drop

Returns a string with the first n characters removed.

fun String.drop(n: Int): String
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1.0

dropLast

Returns a string with the last n characters removed.

fun String.dropLast(n: Int): String
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1.0

dropLastWhile

Returns a string containing all characters except last characters that satisfy the given predicate.

fun String.dropLastWhile(
    predicate: (Char) -> Boolean
): String
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1.0

dropWhile

Returns a string containing all characters except first characters that satisfy the given predicate.

fun String.dropWhile(predicate: (Char) -> Boolean): String
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1.0

elementAtOrElse

Returns a character at the given index or the result of calling the defaultValue function if the index is out of bounds of this char sequence.

fun CharSequence.elementAtOrElse(
    index: Int,
    defaultValue: (Int) -> Char
): Char
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1.0

elementAtOrNull

Returns a character at the given index or null if the index is out of bounds of this char sequence.

fun CharSequence.elementAtOrNull(index: Int): Char?
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1.0

endsWith

Returns true if this char sequence ends with the specified character.

fun CharSequence.endsWith(
    char: Char,
    ignoreCase: Boolean = false
): Boolean

Returns true if this char sequence ends with the specified suffix.

fun CharSequence.endsWith(
    suffix: CharSequence,
    ignoreCase: Boolean = false
): Boolean
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1.0

filter

Returns a string containing only those characters from the original string that match the given predicate.

fun String.filter(predicate: (Char) -> Boolean): String
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1.0

filterIndexed

Returns a string containing only those characters from the original string that match the given predicate.

fun String.filterIndexed(
    predicate: (index: Int, Char) -> Boolean
): String
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1.0

filterIndexedTo

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

fun <C : Appendable> CharSequence.filterIndexedTo(
    destination: C,
    predicate: (index: Int, Char) -> Boolean
): C
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1.0

filterNot

Returns a string containing only those characters from the original string that do not match the given predicate.

fun String.filterNot(predicate: (Char) -> Boolean): String
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1.0

filterNotTo

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

fun <C : Appendable> CharSequence.filterNotTo(
    destination: C,
    predicate: (Char) -> Boolean
): C
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1.0

filterTo

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

fun <C : Appendable> CharSequence.filterTo(
    destination: C,
    predicate: (Char) -> Boolean
): C
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1.0

find

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

fun CharSequence.find(predicate: (Char) -> Boolean): Char?
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1.0

findAnyOf

Finds the first occurrence of any of the specified strings in this char sequence, starting from the specified startIndex and optionally ignoring the case.

fun CharSequence.findAnyOf(
    strings: Collection<String>,
    startIndex: Int = 0,
    ignoreCase: Boolean = false
): Pair<Int, String>?
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1.0

findLast

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

fun CharSequence.findLast(
    predicate: (Char) -> Boolean
): Char?
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1.0

findLastAnyOf

Finds the last occurrence of any of the specified strings in this char sequence, starting from the specified startIndex and optionally ignoring the case.

fun CharSequence.findLastAnyOf(
    strings: Collection<String>,
    startIndex: Int = lastIndex,
    ignoreCase: Boolean = false
): Pair<Int, String>?
Common
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1.0

first

Returns the first character.

fun CharSequence.first(): Char

Returns the first character matching the given predicate.

fun CharSequence.first(predicate: (Char) -> Boolean): Char
Common
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Native
1.5

firstNotNullOf

Returns the first non-null value produced by transform function being applied to characters of this char sequence in iteration order, or throws NoSuchElementException if no non-null value was produced.

fun <R : Any> CharSequence.firstNotNullOf(
    transform: (Char) -> R?
): R
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1.5

firstNotNullOfOrNull

Returns the first non-null value produced by transform function being applied to characters of this char sequence in iteration order, or null if no non-null value was produced.

fun <R : Any> CharSequence.firstNotNullOfOrNull(
    transform: (Char) -> R?
): R?
Common
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1.0

firstOrNull

Returns the first character, or null if the char sequence is empty.

fun CharSequence.firstOrNull(): Char?

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

fun CharSequence.firstOrNull(
    predicate: (Char) -> Boolean
): Char?
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1.0

flatMap

Returns a single list of all elements yielded from results of transform function being invoked on each character of original char sequence.

fun <R> CharSequence.flatMap(
    transform: (Char) -> Iterable<R>
): List<R>
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1.4

flatMapIndexed

Returns a single list of all elements yielded from results of transform function being invoked on each character and its index in the original char sequence.

fun <R> CharSequence.flatMapIndexed(
    transform: (index: Int, Char) -> Iterable<R>
): List<R>
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1.4

flatMapIndexedTo

Appends all elements yielded from results of transform function being invoked on each character and its index in the original char sequence, to the given destination.

fun <R, C : MutableCollection<in R>> CharSequence.flatMapIndexedTo(
    destination: C,
    transform: (index: Int, Char) -> Iterable<R>
): C
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1.0

flatMapTo

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

fun <R, C : MutableCollection<in R>> CharSequence.flatMapTo(
    destination: C,
    transform: (Char) -> Iterable<R>
): C
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1.0

fold

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

fun <R> CharSequence.fold(
    initial: R,
    operation: (acc: R, Char) -> R
): R
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1.0

foldIndexed

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

fun <R> CharSequence.foldIndexed(
    initial: R,
    operation: (index: Int, acc: R, Char) -> R
): R
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1.0

foldRight

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

fun <R> CharSequence.foldRight(
    initial: R,
    operation: (Char, acc: R) -> R
): R
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1.0

foldRightIndexed

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

fun <R> CharSequence.foldRightIndexed(
    initial: R,
    operation: (index: Int, Char, acc: R) -> R
): R
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1.0

forEach

Performs the given action on each character.

fun CharSequence.forEach(action: (Char) -> Unit)
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1.0

forEachIndexed

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

fun CharSequence.forEachIndexed(
    action: (index: Int, Char) -> Unit)
JVM
1.0

format

Uses this string as a format string and returns a string obtained by substituting format specifiers in the format string with the provided arguments, using the default locale.

fun String.format(vararg args: Any?): String

Uses this string as a format string and returns a string obtained by substituting format specifiers in the format string with the provided arguments, using the specified locale. If locale is null then no localization is applied.

fun String.format(locale: Locale?, vararg args: Any?): String
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1.0

getOrElse

Returns a character at the given index or the result of calling the defaultValue function if the index is out of bounds of this char sequence.

fun CharSequence.getOrElse(
    index: Int,
    defaultValue: (Int) -> Char
): Char
Common
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1.0

getOrNull

Returns a character at the given index or null if the index is out of bounds of this char sequence.

fun CharSequence.getOrNull(index: Int): Char?
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1.0

groupBy

Groups characters of the original char sequence by the key returned by the given keySelector function applied to each character and returns a map where each group key is associated with a list of corresponding characters.

fun <K> CharSequence.groupBy(
    keySelector: (Char) -> K
): Map<K, List<Char>>

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

fun <K, V> CharSequence.groupBy(
    keySelector: (Char) -> K,
    valueTransform: (Char) -> V
): Map<K, List<V>>
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1.0

groupByTo

Groups characters of the original char sequence by the key returned by the given keySelector function applied to each character and puts to the destination map each group key associated with a list of corresponding characters.

fun <K, M : MutableMap<in K, MutableList<Char>>> CharSequence.groupByTo(
    destination: M,
    keySelector: (Char) -> K
): M

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

fun <K, V, M : MutableMap<in K, MutableList<V>>> CharSequence.groupByTo(
    destination: M,
    keySelector: (Char) -> K,
    valueTransform: (Char) -> V
): M
Common
JVM
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Native
1.1

groupingBy

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

fun <K> CharSequence.groupingBy(
    keySelector: (Char) -> K
): Grouping<Char, K>
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1.0

hasSurrogatePairAt

Returns true if this CharSequence has Unicode surrogate pair at the specified index.

fun CharSequence.hasSurrogatePairAt(index: Int): Boolean
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1.9

hexToByte

Parses a Byte value from this string using the specified format.

fun String.hexToByte(
    format: HexFormat = HexFormat.Default
): Byte
Common
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Native
1.9

hexToByteArray

Parses a byte array from this string using the specified format.

fun String.hexToByteArray(
    format: HexFormat = HexFormat.Default
): ByteArray
Common
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1.9

hexToInt

Parses an Int value from this string using the specified format.

fun String.hexToInt(
    format: HexFormat = HexFormat.Default
): Int
Common
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1.9

hexToLong

Parses a Long value from this string using the specified format.

fun String.hexToLong(
    format: HexFormat = HexFormat.Default
): Long
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1.9

hexToShort

Parses a Short value from this string using the specified format.

fun String.hexToShort(
    format: HexFormat = HexFormat.Default
): Short
Common
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Native
1.9

hexToUByte

Parses an UByte value from this string using the specified format.

fun String.hexToUByte(
    format: HexFormat = HexFormat.Default
): UByte
Common
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Native
1.9

hexToUByteArray

Parses a byte array from this string using the specified format.

fun String.hexToUByteArray(
    format: HexFormat = HexFormat.Default
): UByteArray
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JVM
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1.9

hexToUInt

Parses an UInt value from this string using the specified format.

fun String.hexToUInt(
    format: HexFormat = HexFormat.Default
): UInt
Common
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1.9

hexToULong

Parses an ULong value from this string using the specified format.

fun String.hexToULong(
    format: HexFormat = HexFormat.Default
): ULong
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1.9

hexToUShort

Parses an UShort value from this string using the specified format.

fun String.hexToUShort(
    format: HexFormat = HexFormat.Default
): UShort
Common
JVM
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1.3

ifBlank

Returns this char sequence if it is not empty and doesn't consist solely of whitespace characters, or the result of calling defaultValue function otherwise.

fun <C, R> C.ifBlank(
    defaultValue: () -> R
): R where C : CharSequence, C : R
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1.3

ifEmpty

Returns this char sequence if it's not empty or the result of calling defaultValue function if the char sequence is empty.

fun <C, R> C.ifEmpty(
    defaultValue: () -> R
): R where C : CharSequence, C : R
Common
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1.0

indexOf

Returns the index within this string of the first occurrence of the specified character, starting from the specified startIndex.

fun CharSequence.indexOf(
    char: Char,
    startIndex: Int = 0,
    ignoreCase: Boolean = false
): Int

Returns the index within this char sequence of the first occurrence of the specified string, starting from the specified startIndex.

fun CharSequence.indexOf(
    string: String,
    startIndex: Int = 0,
    ignoreCase: Boolean = false
): Int
Common
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1.0

indexOfAny

Finds the index of the first occurrence of any of the specified chars in this char sequence, starting from the specified startIndex and optionally ignoring the case.

fun CharSequence.indexOfAny(
    chars: CharArray,
    startIndex: Int = 0,
    ignoreCase: Boolean = false
): Int

Finds the index of the first occurrence of any of the specified strings in this char sequence, starting from the specified startIndex and optionally ignoring the case.

fun CharSequence.indexOfAny(
    strings: Collection<String>,
    startIndex: Int = 0,
    ignoreCase: Boolean = false
): Int
Common
JVM
JS
Native
1.0

indexOfFirst

Returns index of the first character matching the given predicate, or -1 if the char sequence does not contain such character.

fun CharSequence.indexOfFirst(
    predicate: (Char) -> Boolean
): Int
Common
JVM
JS
Native
1.0

indexOfLast

Returns index of the last character matching the given predicate, or -1 if the char sequence does not contain such character.

fun CharSequence.indexOfLast(
    predicate: (Char) -> Boolean
): Int
JVM
1.0

intern

Returns a canonical representation for this string object.

fun String.intern(): String
Common
JVM
JS
Native
1.0

isBlank

Returns true if this char sequence is empty or consists solely of whitespace characters according to Char.isWhitespace.

fun CharSequence.isBlank(): Boolean
Common
JVM
JS
Native
1.0

isEmpty

Returns true if this char sequence is empty (contains no characters).

fun CharSequence.isEmpty(): Boolean
Common
JVM
JS
Native
1.0

isNotBlank

Returns true if this char sequence is not empty and contains some characters except whitespace characters.

fun CharSequence.isNotBlank(): Boolean
Common
JVM
JS
Native
1.0

isNotEmpty

Returns true if this char sequence is not empty.

fun CharSequence.isNotEmpty(): Boolean
Common
JVM
JS
Native
1.0

isNullOrBlank

Returns true if this nullable char sequence is either null or empty or consists solely of whitespace characters.

fun CharSequence?.isNullOrBlank(): Boolean
Common
JVM
JS
Native
1.0

isNullOrEmpty

Returns true if this nullable char sequence is either null or empty.

fun CharSequence?.isNullOrEmpty(): Boolean
Common
JVM
JS
Native
1.0

iterator

Iterator for characters of the given char sequence.

operator fun CharSequence.iterator(): CharIterator
Common
JVM
JS
Native
1.0

last

Returns the last character.

fun CharSequence.last(): Char

Returns the last character matching the given predicate.

fun CharSequence.last(predicate: (Char) -> Boolean): Char
Common
JVM
JS
Native
1.0

lastIndexOf

Returns the index within this char sequence of the last occurrence of the specified character, starting from the specified startIndex.

fun CharSequence.lastIndexOf(
    char: Char,
    startIndex: Int = lastIndex,
    ignoreCase: Boolean = false
): Int

Returns the index within this char sequence of the last occurrence of the specified string, starting from the specified startIndex.

fun CharSequence.lastIndexOf(
    string: String,
    startIndex: Int = lastIndex,
    ignoreCase: Boolean = false
): Int
Common
JVM
JS
Native
1.0

lastIndexOfAny

Finds the index of the last occurrence of any of the specified chars in this char sequence, starting from the specified startIndex and optionally ignoring the case.

fun CharSequence.lastIndexOfAny(
    chars: CharArray,
    startIndex: Int = lastIndex,
    ignoreCase: Boolean = false
): Int

Finds the index of the last occurrence of any of the specified strings in this char sequence, starting from the specified startIndex and optionally ignoring the case.

fun CharSequence.lastIndexOfAny(
    strings: Collection<String>,
    startIndex: Int = lastIndex,
    ignoreCase: Boolean = false
): Int
Common
JVM
JS
Native
1.0

lastOrNull

Returns the last character, or null if the char sequence is empty.

fun CharSequence.lastOrNull(): Char?

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

fun CharSequence.lastOrNull(
    predicate: (Char) -> Boolean
): Char?
Common
JVM
JS
Native
1.0

lines

Splits this char sequence to a list of lines delimited by any of the following character sequences: CRLF, LF or CR.

fun CharSequence.lines(): List<String>
Common
JVM
JS
Native
1.0

lineSequence

Splits this char sequence to a sequence of lines delimited by any of the following character sequences: CRLF, LF or CR.

fun CharSequence.lineSequence(): Sequence<String>
JVM
1.5

lowercase

Returns a copy of this string converted to lower case using the rules of the specified locale.

fun String.lowercase(locale: Locale): String
Common
JVM
JS
Native
1.0

map

Returns a list containing the results of applying the given transform function to each character in the original char sequence.

fun <R> CharSequence.map(transform: (Char) -> R): List<R>
Common
JVM
JS
Native
1.0

mapIndexed

Returns a list containing the results of applying the given transform function to each character and its index in the original char sequence.

fun <R> CharSequence.mapIndexed(
    transform: (index: Int, Char) -> R
): List<R>
Common
JVM
JS
Native
1.0

mapIndexedNotNull

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

fun <R : Any> CharSequence.mapIndexedNotNull(
    transform: (index: Int, Char) -> R?
): List<R>
Common
JVM
JS
Native
1.0

mapIndexedNotNullTo

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

fun <R : Any, C : MutableCollection<in R>> CharSequence.mapIndexedNotNullTo(
    destination: C,
    transform: (index: Int, Char) -> R?
): C
Common
JVM
JS
Native
1.0

mapIndexedTo

Applies the given transform function to each character and its index in the original char sequence and appends the results to the given destination.

fun <R, C : MutableCollection<in R>> CharSequence.mapIndexedTo(
    destination: C,
    transform: (index: Int, Char) -> R
): C
Common
JVM
JS
Native
1.0

mapNotNull

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

fun <R : Any> CharSequence.mapNotNull(
    transform: (Char) -> R?
): List<R>
Common
JVM
JS
Native
1.0

mapNotNullTo

Applies the given transform function to each character in the original char sequence and appends only the non-null results to the given destination.

fun <R : Any, C : MutableCollection<in R>> CharSequence.mapNotNullTo(
    destination: C,
    transform: (Char) -> R?
): C
Common
JVM
JS
Native
1.0

mapTo

Applies the given transform function to each character of the original char sequence and appends the results to the given destination.

fun <R, C : MutableCollection<in R>> CharSequence.mapTo(
    destination: C,
    transform: (Char) -> R
): C
JS
1.1

match

fun String.match(regex: String): Array<String>?

matches

Common
JVM
JS
Native
1.0

Returns true if this char sequence matches the given regular expression.

infix fun CharSequence.matches(regex: Regex): Boolean
JS
1.1
fun String.matches(regex: String): Boolean
Common
JVM
JS
Native
1.4

maxByOrNull

Returns the first character yielding the largest value of the given function or null if there are no characters.

fun <R : Comparable<R>> CharSequence.maxByOrNull(
    selector: (Char) -> R
): Char?
Common
JVM
JS
Native
1.4

maxOf

Returns the largest value among all values produced by selector function applied to each character in the char sequence.

fun <R : Comparable<R>> any_iterable<R>.maxOf(
    selector: (Char) -> R
): R
Common
JVM
JS
Native
1.4

maxOfOrNull

Returns the largest value among all values produced by selector function applied to each character in the char sequence or null if there are no characters.

fun <R : Comparable<R>> any_iterable<R>.maxOfOrNull(
    selector: (Char) -> R
): R?
Common
JVM
JS
Native
1.4

maxOfWith

Returns the largest value according to the provided comparator among all values produced by selector function applied to each character in the char sequence.

fun <R> CharSequence.maxOfWith(
    comparator: Comparator<in R>,
    selector: (Char) -> R
): R
Common
JVM
JS
Native
1.4

maxOfWithOrNull

Returns the largest value according to the provided comparator among all values produced by selector function applied to each character in the char sequence or null if there are no characters.

fun <R> CharSequence.maxOfWithOrNull(
    comparator: Comparator<in R>,
    selector: (Char) -> R
): R?
Common
JVM
JS
Native
1.4

maxOrNull

Returns the largest character or null if there are no characters.

fun CharSequence.maxOrNull(): Char?

maxWith

Common
JVM
JS
Native
1.7

Returns the first character having the largest value according to the provided comparator.

fun CharSequence.maxWith(
    comparator: Comparator<in Char>
): Char
JVM
1.0
fun CharSequence.maxWith(
    comparator: Comparator<in Char>
): Char?
Common
JVM
JS
Native
1.4

maxWithOrNull

Returns the first character having the largest value according to the provided comparator or null if there are no characters.

fun CharSequence.maxWithOrNull(
    comparator: Comparator<in Char>
): Char?
Common
JVM
JS
Native
1.4

minByOrNull

Returns the first character yielding the smallest value of the given function or null if there are no characters.

fun <R : Comparable<R>> CharSequence.minByOrNull(
    selector: (Char) -> R
): Char?
Common
JVM
JS
Native
1.4

minOf

Returns the smallest value among all values produced by selector function applied to each character in the char sequence.

fun <R : Comparable<R>> any_iterable<R>.minOf(
    selector: (Char) -> R
): R
Common
JVM
JS
Native
1.4

minOfOrNull

Returns the smallest value among all values produced by selector function applied to each character in the char sequence or null if there are no characters.

fun <R : Comparable<R>> any_iterable<R>.minOfOrNull(
    selector: (Char) -> R
): R?
Common
JVM
JS
Native
1.4

minOfWith

Returns the smallest value according to the provided comparator among all values produced by selector function applied to each character in the char sequence.

fun <R> CharSequence.minOfWith(
    comparator: Comparator<in R>,
    selector: (Char) -> R
): R
Common
JVM
JS
Native
1.4

minOfWithOrNull

Returns the smallest value according to the provided comparator among all values produced by selector function applied to each character in the char sequence or null if there are no characters.

fun <R> CharSequence.minOfWithOrNull(
    comparator: Comparator<in R>,
    selector: (Char) -> R
): R?
Common
JVM
JS
Native
1.4

minOrNull

Returns the smallest character or null if there are no characters.

fun CharSequence.minOrNull(): Char?

minWith

Common
JVM
JS
Native
1.7

Returns the first character having the smallest value according to the provided comparator.

fun CharSequence.minWith(
    comparator: Comparator<in Char>
): Char
JVM
1.0
fun CharSequence.minWith(
    comparator: Comparator<in Char>
): Char?
Common
JVM
JS
Native
1.4

minWithOrNull

Returns the first character having the smallest value according to the provided comparator or null if there are no characters.

fun CharSequence.minWithOrNull(
    comparator: Comparator<in Char>
): Char?
Common
JVM
JS
Native
1.0

none

Returns true if the char sequence has no characters.

fun CharSequence.none(): Boolean

Returns true if no characters match the given predicate.

fun CharSequence.none(predicate: (Char) -> Boolean): Boolean
JVM
1.0

offsetByCodePoints

Returns the index within this string that is offset from the given index by codePointOffset code points.

fun String.offsetByCodePoints(
    index: Int,
    codePointOffset: Int
): Int
Common
JVM
JS
Native
1.1

onEach

Performs the given action on each character and returns the char sequence itself afterwards.

fun <S : CharSequence> S.onEach(action: (Char) -> Unit): S
Common
JVM
JS
Native
1.4

onEachIndexed

Performs the given action on each character, providing sequential index with the character, and returns the char sequence itself afterwards.

fun <S : CharSequence> S.onEachIndexed(
    action: (index: Int, Char) -> Unit
): S
Common
JVM
JS
Native
1.0

orEmpty

Returns the string if it is not null, or the empty string otherwise.

fun String?.orEmpty(): String
Common
JVM
JS
Native
1.0

padEnd

Pads the string to the specified length at the end with the specified character or space.

fun String.padEnd(length: Int, padChar: Char = ' '): String
Common
JVM
JS
Native
1.0

padStart

Pads the string to the specified length at the beginning with the specified character or space.

fun String.padStart(length: Int, padChar: Char = ' '): String
Common
JVM
JS
Native
1.0

partition

Splits the original string into pair of strings, where first string contains characters for which predicate yielded true, while second string contains characters for which predicate yielded false.

fun String.partition(
    predicate: (Char) -> Boolean
): Pair<String, String>
Common
JVM
JS
Native
1.0

prependIndent

Prepends indent to every line of the original string.

fun String.prependIndent(indent: String = " "): String
Common
JVM
JS
Native
1.3

random

Returns a random character from this char sequence.

fun CharSequence.random(): Char

Returns a random character from this char sequence using the specified source of randomness.

fun CharSequence.random(random: Random): Char
Common
JVM
JS
Native
1.4

randomOrNull

Returns a random character from this char sequence, or null if this char sequence is empty.

fun CharSequence.randomOrNull(): Char?

Returns a random character from this char sequence using the specified source of randomness, or null if this char sequence is empty.

fun CharSequence.randomOrNull(random: Random): Char?
Common
JVM
JS
Native
1.0

rangeTo

Creates a range from this Comparable value to the specified that value.

operator fun <T : Comparable<T>> T.rangeTo(
    that: T
): ClosedRange<T>
Common
JVM
JS
Native
1.9

rangeUntil

Creates an open-ended range from this Comparable value to the specified that value.

operator fun <T : Comparable<T>> T.rangeUntil(
    that: T
): OpenEndRange<T>
JVM
1.0

reader

Creates a new reader for the string.

fun String.reader(): StringReader
Common
JVM
JS
Native
1.0

reduce

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

fun CharSequence.reduce(
    operation: (acc: Char, Char) -> Char
): Char
Common
JVM
JS
Native
1.0

reduceIndexed

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

fun CharSequence.reduceIndexed(
    operation: (index: Int, acc: Char, Char) -> Char
): Char
Common
JVM
JS
Native
1.4

reduceIndexedOrNull

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

fun CharSequence.reduceIndexedOrNull(
    operation: (index: Int, acc: Char, Char) -> Char
): Char?
Common
JVM
JS
Native
1.4

reduceOrNull

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

fun CharSequence.reduceOrNull(
    operation: (acc: Char, Char) -> Char
): Char?
Common
JVM
JS
Native
1.0

reduceRight

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

fun CharSequence.reduceRight(
    operation: (Char, acc: Char) -> Char
): Char
Common
JVM
JS
Native
1.0

reduceRightIndexed

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

fun CharSequence.reduceRightIndexed(
    operation: (index: Int, Char, acc: Char) -> Char
): Char
Common
JVM
JS
Native
1.4

reduceRightIndexedOrNull

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

fun CharSequence.reduceRightIndexedOrNull(
    operation: (index: Int, Char, acc: Char) -> Char
): Char?
Common
JVM
JS
Native
1.4

reduceRightOrNull

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

fun CharSequence.reduceRightOrNull(
    operation: (Char, acc: Char) -> Char
): Char?
Native
1.3

refTo

fun String.refTo(index: Int): CValuesRef<COpaque>
Common
JVM
JS
Native
1.0

removePrefix

If this string starts with the given prefix, returns a copy of this string with the prefix removed. Otherwise, returns this string.

fun String.removePrefix(prefix: CharSequence): String
Common
JVM
JS
Native
1.0

removeRange

Removes the part of a string at a given range.

fun String.removeRange(
    startIndex: Int,
    endIndex: Int
): String

Removes the part of a string at the given range.

fun String.removeRange(range: IntRange): String
Common
JVM
JS
Native
1.0

removeSuffix

If this string ends with the given suffix, returns a copy of this string with the suffix removed. Otherwise, returns this string.

fun String.removeSuffix(suffix: CharSequence): String
Common
JVM
JS
Native
1.0

removeSurrounding

Removes from a string both the given prefix and suffix if and only if it starts with the prefix and ends with the suffix. Otherwise, returns this string unchanged.

fun String.removeSurrounding(
    prefix: CharSequence,
    suffix: CharSequence
): String

Removes the given delimiter string from both the start and the end of this string if and only if it starts with and ends with the delimiter. Otherwise, returns this string unchanged.

fun String.removeSurrounding(delimiter: CharSequence): String
Common
JVM
JS
Native
1.0

replace

Returns a new string obtained by replacing each substring of this char sequence that matches the given regular expression with the given replacement.

fun CharSequence.replace(
    regex: Regex,
    replacement: String
): String

Returns a new string obtained by replacing each substring of this char sequence that matches the given regular expression with the result of the given function transform that takes MatchResult and returns a string to be used as a replacement for that match.

fun CharSequence.replace(
    regex: Regex,
    transform: (MatchResult) -> CharSequence
): String
Common
JVM
JS
Native
1.0

replaceAfter

Replace part of string after the first occurrence of given delimiter with the replacement string. If the string does not contain the delimiter, returns missingDelimiterValue which defaults to the original string.

fun String.replaceAfter(
    delimiter: Char,
    replacement: String,
    missingDelimiterValue: String = this
): String
fun String.replaceAfter(
    delimiter: String,
    replacement: String,
    missingDelimiterValue: String = this
): String
Common
JVM
JS
Native
1.0

replaceAfterLast

Replace part of string after the last occurrence of given delimiter with the replacement string. If the string does not contain the delimiter, returns missingDelimiterValue which defaults to the original string.

fun String.replaceAfterLast(
    delimiter: String,
    replacement: String,
    missingDelimiterValue: String = this
): String
fun String.replaceAfterLast(
    delimiter: Char,
    replacement: String,
    missingDelimiterValue: String = this
): String
Common
JVM
JS
Native
1.0

replaceBefore

Replace part of string before the first occurrence of given delimiter with the replacement string. If the string does not contain the delimiter, returns missingDelimiterValue which defaults to the original string.

fun String.replaceBefore(
    delimiter: Char,
    replacement: String,
    missingDelimiterValue: String = this
): String
fun String.replaceBefore(
    delimiter: String,
    replacement: String,
    missingDelimiterValue: String = this
): String
Common
JVM
JS
Native
1.0

replaceBeforeLast

Replace part of string before the last occurrence of given delimiter with the replacement string. If the string does not contain the delimiter, returns missingDelimiterValue which defaults to the original string.

fun String.replaceBeforeLast(
    delimiter: Char,
    replacement: String,
    missingDelimiterValue: String = this
): String
fun String.replaceBeforeLast(
    delimiter: String,
    replacement: String,
    missingDelimiterValue: String = this
): String
Common
JVM
JS
Native
1.0

replaceFirst

Replaces the first occurrence of the given regular expression regex in this char sequence with specified replacement expression.

fun CharSequence.replaceFirst(
    regex: Regex,
    replacement: String
): String
Common
JVM
JS
Native
1.5

replaceFirstChar

Returns a copy of this string having its first character replaced with the result of the specified transform, or the original string if it's empty.

fun String.replaceFirstChar(
    transform: (Char) -> Char
): String
fun String.replaceFirstChar(
    transform: (Char) -> CharSequence
): String
Common
JVM
JS
Native
1.0

replaceIndent

Detects a common minimal indent like it does trimIndent and replaces it with the specified newIndent.

fun String.replaceIndent(newIndent: String = ""): String
Common
JVM
JS
Native
1.0

replaceIndentByMargin

Detects indent by marginPrefix as it does trimMargin and replace it with newIndent.

fun String.replaceIndentByMargin(
    newIndent: String = "",
    marginPrefix: String = "|"
): String
Common
JVM
JS
Native
1.0

replaceRange

Replaces the part of the string at the given range with the replacement char sequence.

fun String.replaceRange(
    startIndex: Int,
    endIndex: Int,
    replacement: CharSequence
): String

Replace the part of string at the given range with the replacement string.

fun String.replaceRange(
    range: IntRange,
    replacement: CharSequence
): String
Common
JVM
JS
Native
1.0

reversed

Returns a string with characters in reversed order.

fun String.reversed(): String
Common
JVM
JS
Native
1.4

runningFold

Returns a list containing successive accumulation values generated by applying operation from left to right to each character and current accumulator value that starts with initial value.

fun <R> CharSequence.runningFold(
    initial: R,
    operation: (acc: R, Char) -> R
): List<R>
Common
JVM
JS
Native
1.4

runningFoldIndexed

Returns a list containing successive accumulation values generated by applying operation from left to right to each character, its index in the original char sequence and current accumulator value that starts with initial value.

fun <R> CharSequence.runningFoldIndexed(
    initial: R,
    operation: (index: Int, acc: R, Char) -> R
): List<R>
Common
JVM
JS
Native
1.4

runningReduce

Returns a list containing successive accumulation values generated by applying operation from left to right to each character and current accumulator value that starts with the first character of this char sequence.

fun CharSequence.runningReduce(
    operation: (acc: Char, Char) -> Char
): List<Char>
Common
JVM
JS
Native
1.4

runningReduceIndexed

Returns a list containing successive accumulation values generated by applying operation from left to right to each character, its index in the original char sequence and current accumulator value that starts with the first character of this char sequence.

fun CharSequence.runningReduceIndexed(
    operation: (index: Int, acc: Char, Char) -> Char
): List<Char>
Common
JVM
JS
Native
1.4

scan

Returns a list containing successive accumulation values generated by applying operation from left to right to each character and current accumulator value that starts with initial value.

fun <R> CharSequence.scan(
    initial: R,
    operation: (acc: R, Char) -> R
): List<R>
Common
JVM
JS
Native
1.4

scanIndexed

Returns a list containing successive accumulation values generated by applying operation from left to right to each character, its index in the original char sequence and current accumulator value that starts with initial value.

fun <R> CharSequence.scanIndexed(
    initial: R,
    operation: (index: Int, acc: R, Char) -> R
): List<R>
Common
JVM
JS
Native
1.0

single

Returns the single character, or throws an exception if the char sequence is empty or has more than one character.

fun CharSequence.single(): Char

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

fun CharSequence.single(predicate: (Char) -> Boolean): Char
Common
JVM
JS
Native
1.0

singleOrNull

Returns single character, or null if the char sequence is empty or has more than one character.

fun CharSequence.singleOrNull(): Char?

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

fun CharSequence.singleOrNull(
    predicate: (Char) -> Boolean
): Char?
Common
JVM
JS
Native
1.0

slice

Returns a string containing characters of the original string at the specified range of indices.

fun String.slice(indices: IntRange): String

Returns a string containing characters of the original string at specified indices.

fun String.slice(indices: Iterable<Int>): String

split

Common
JVM
JS
Native
1.0

Splits this char sequence to a list of strings around occurrences of the specified delimiters.

fun CharSequence.split(
    vararg delimiters: String,
    ignoreCase: Boolean = false,
    limit: Int = 0
): List<String>
fun CharSequence.split(
    vararg delimiters: Char,
    ignoreCase: Boolean = false,
    limit: Int = 0
): List<String>
Common
JVM
JS
Native
1.0

Splits this char sequence to a list of strings around matches of the given regular expression.

fun CharSequence.split(
    regex: Regex,
    limit: Int = 0
): List<String>
JVM
1.0

Splits this char sequence around matches of the given regular expression.

fun CharSequence.split(
    regex: Pattern,
    limit: Int = 0
): List<String>
Common
JVM
JS
Native
1.0

splitToSequence

Splits this char sequence to a sequence of strings around occurrences of the specified delimiters.

fun CharSequence.splitToSequence(
    vararg delimiters: String,
    ignoreCase: Boolean = false,
    limit: Int = 0
): Sequence<String>
fun CharSequence.splitToSequence(
    vararg delimiters: Char,
    ignoreCase: Boolean = false,
    limit: Int = 0
): Sequence<String>

Splits this char sequence to a sequence of strings around matches of the given regular expression.

fun CharSequence.splitToSequence(
    regex: Regex,
    limit: Int = 0
): Sequence<String>
Common
JVM
JS
Native
1.0

startsWith

Returns true if this char sequence starts with the specified character.

fun CharSequence.startsWith(
    char: Char,
    ignoreCase: Boolean = false
): Boolean

Returns true if this char sequence starts with the specified prefix.

fun CharSequence.startsWith(
    prefix: CharSequence,
    ignoreCase: Boolean = false
): Boolean

Returns true if a substring of this char sequence starting at the specified offset startIndex starts with the specified prefix.

fun CharSequence.startsWith(
    prefix: CharSequence,
    startIndex: Int,
    ignoreCase: Boolean = false
): Boolean
Common
JVM
JS
Native
1.0

subSequence

Returns a subsequence of this char sequence.

fun String.subSequence(start: Int, end: Int): CharSequence

Returns a subsequence of this char sequence specified by the given range of indices.

fun CharSequence.subSequence(range: IntRange): CharSequence
Common
JVM
JS
Native
1.0

substring

Returns a substring specified by the given range of indices.

fun String.substring(range: IntRange): String
Common
JVM
JS
Native
1.0

substringAfter

Returns a substring after the first occurrence of delimiter. If the string does not contain the delimiter, returns missingDelimiterValue which defaults to the original string.

fun String.substringAfter(
    delimiter: Char,
    missingDelimiterValue: String = this
): String
fun String.substringAfter(
    delimiter: String,
    missingDelimiterValue: String = this
): String
Common
JVM
JS
Native
1.0

substringAfterLast

Returns a substring after the last occurrence of delimiter. If the string does not contain the delimiter, returns missingDelimiterValue which defaults to the original string.

fun String.substringAfterLast(
    delimiter: Char,
    missingDelimiterValue: String = this
): String
fun String.substringAfterLast(
    delimiter: String,
    missingDelimiterValue: String = this
): String
Common
JVM
JS
Native
1.0

substringBefore

Returns a substring before the first occurrence of delimiter. If the string does not contain the delimiter, returns missingDelimiterValue which defaults to the original string.

fun String.substringBefore(
    delimiter: Char,
    missingDelimiterValue: String = this
): String
fun String.substringBefore(
    delimiter: String,
    missingDelimiterValue: String = this
): String
Common
JVM
JS
Native
1.0

substringBeforeLast

Returns a substring before the last occurrence of delimiter. If the string does not contain the delimiter, returns missingDelimiterValue which defaults to the original string.

fun String.substringBeforeLast(
    delimiter: Char,
    missingDelimiterValue: String = this
): String
fun String.substringBeforeLast(
    delimiter: String,
    missingDelimiterValue: String = this
): String
Common
JVM
JS
Native
1.0

sumBy

Returns the sum of all values produced by selector function applied to each character in the char sequence.

fun CharSequence.sumBy(selector: (Char) -> Int): Int
Common
JVM
JS
Native
1.0

sumByDouble

Returns the sum of all values produced by selector function applied to each character in the char sequence.

fun CharSequence.sumByDouble(
    selector: (Char) -> Double
): Double

sumOf

Returns the sum of all values produced by selector function applied to each character in the char sequence.

Common
JVM
JS
Native
1.4
fun CharSequence.sumOf(selector: (Char) -> Double): Double
Common
JVM
JS
Native
1.4
fun CharSequence.sumOf(selector: (Char) -> Int): Int
Common
JVM
JS
Native
1.4
fun CharSequence.sumOf(selector: (Char) -> Long): Long
Common
JVM
JS
Native
1.5
fun CharSequence.sumOf(selector: (Char) -> UInt): UInt
Common
JVM
JS
Native
1.5
fun CharSequence.sumOf(selector: (Char) -> ULong): ULong
JVM
1.4
fun CharSequence.sumOf(
    selector: (Char) -> BigDecimal
): BigDecimal
JVM
1.4
fun CharSequence.sumOf(
    selector: (Char) -> BigInteger
): BigInteger
Common
JVM
JS
Native
1.0

take

Returns a string containing the first n characters from this string, or the entire string if this string is shorter.

fun String.take(n: Int): String
Common
JVM
JS
Native
1.0

takeLast

Returns a string containing the last n characters from this string, or the entire string if this string is shorter.

fun String.takeLast(n: Int): String
Common
JVM
JS
Native
1.0

takeLastWhile

Returns a string containing last characters that satisfy the given predicate.

fun String.takeLastWhile(
    predicate: (Char) -> Boolean
): String
Common
JVM
JS
Native
1.0

takeWhile

Returns a string containing the first characters that satisfy the given predicate.

fun String.takeWhile(predicate: (Char) -> Boolean): String
JVM
1.2

toBigDecimal

Parses the string as a java.math.BigDecimal number and returns the result.

fun String.toBigDecimal(): BigDecimal
fun String.toBigDecimal(mathContext: MathContext): BigDecimal
JVM
1.2

toBigDecimalOrNull

Parses the string as a java.math.BigDecimal number and returns the result or null if the string is not a valid representation of a number.

fun String.toBigDecimalOrNull(): BigDecimal?
fun String.toBigDecimalOrNull(
    mathContext: MathContext
): BigDecimal?
JVM
1.2

toBigInteger

Parses the string as a java.math.BigInteger number and returns the result.

fun String.toBigInteger(): BigInteger
fun String.toBigInteger(radix: Int): BigInteger
JVM
1.2

toBigIntegerOrNull

Parses the string as a java.math.BigInteger number and returns the result or null if the string is not a valid representation of a number.

fun String.toBigIntegerOrNull(): BigInteger?
fun String.toBigIntegerOrNull(radix: Int): BigInteger?
Common
JVM
JS
Native
1.5

toBooleanStrict

Returns true if the content of this string is equal to the word "true", false if it is equal to "false", and throws an exception otherwise.

fun String.toBooleanStrict(): Boolean
Common
JVM
JS
Native
1.5

toBooleanStrictOrNull

Returns true if the content of this string is equal to the word "true", false if it is equal to "false", and null otherwise.

fun String.toBooleanStrictOrNull(): Boolean?
JVM
1.0

toByteArray

Encodes the contents of this string using the specified character set and returns the resulting byte array.

fun String.toByteArray(
    charset: Charset = Charsets.UTF_8
): ByteArray
Common
JVM
JS
Native
1.1

toByteOrNull

Parses the string as a signed Byte number and returns the result or null if the string is not a valid representation of a number.

fun String.toByteOrNull(): Byte?
fun String.toByteOrNull(radix: Int): Byte?
Common
JVM
JS
Native
1.0

toCollection

Appends all characters to the given destination collection.

fun <C : MutableCollection<in Char>> CharSequence.toCollection(
    destination: C
): C
Common
JVM
JS
Native
1.0

toHashSet

Returns a new HashSet of all characters.

fun CharSequence.toHashSet(): HashSet<Char>
Common
JVM
JS
Native
1.1

toIntOrNull

Parses the string as an Int number and returns the result or null if the string is not a valid representation of a number.

fun String.toIntOrNull(): Int?
fun String.toIntOrNull(radix: Int): Int?
Common
JVM
JS
Native
1.0

toList

Returns a List containing all characters.

fun CharSequence.toList(): List<Char>
Common
JVM
JS
Native
1.1

toLongOrNull

Parses the string as a Long number and returns the result or null if the string is not a valid representation of a number.

fun String.toLongOrNull(): Long?
fun String.toLongOrNull(radix: Int): Long?
JVM
1.0

toLowerCase

Returns a copy of this string converted to lower case using the rules of the specified locale.

fun String.toLowerCase(locale: Locale): String
Common
JVM
JS
Native
1.0

toMutableList

Returns a new MutableList filled with all characters of this char sequence.

fun CharSequence.toMutableList(): MutableList<Char>
JVM
1.0

toPattern

Converts the string into a regular expression Pattern optionally with the specified flags from Pattern or'd together so that strings can be split or matched on.

fun String.toPattern(flags: Int = 0): Pattern
Common
JVM
JS
Native
1.0

toRegex

Converts the string into a regular expression Regex with the default options.

fun String.toRegex(): Regex

Converts the string into a regular expression Regex with the specified single option.

fun String.toRegex(option: RegexOption): Regex

Converts the string into a regular expression Regex with the specified set of options.

fun String.toRegex(options: Set<RegexOption>): Regex
Common
JVM
JS
Native
1.0

toSet

Returns a Set of all characters.

fun CharSequence.toSet(): Set<Char>
Common
JVM
JS
Native
1.1

toShortOrNull

Parses the string as a Short number and returns the result or null if the string is not a valid representation of a number.

fun String.toShortOrNull(): Short?
fun String.toShortOrNull(radix: Int): Short?
JVM
1.0

toSortedSet

Returns a new SortedSet of all characters.

fun CharSequence.toSortedSet(): SortedSet<Char>
Common
JVM
JS
Native
1.5

toUByte

Parses the string as a signed UByte number and returns the result.

fun String.toUByte(): UByte
fun String.toUByte(radix: Int): UByte
Common
JVM
JS
Native
1.5

toUByteOrNull

Parses the string as an UByte number and returns the result or null if the string is not a valid representation of a number.

fun String.toUByteOrNull(): UByte?
fun String.toUByteOrNull(radix: Int): UByte?
Common
JVM
JS
Native
1.5

toUInt

Parses the string as an UInt number and returns the result.

fun String.toUInt(): UInt
fun String.toUInt(radix: Int): UInt
Common
JVM
JS
Native
1.5

toUIntOrNull

Parses the string as an UInt number and returns the result or null if the string is not a valid representation of a number.

fun String.toUIntOrNull(): UInt?
fun String.toUIntOrNull(radix: Int): UInt?
Common
JVM
JS
Native
1.5

toULong

Parses the string as a ULong number and returns the result.

fun String.toULong(): ULong
fun String.toULong(radix: Int): ULong
Common
JVM
JS
Native
1.5

toULongOrNull

Parses the string as an ULong number and returns the result or null if the string is not a valid representation of a number.

fun String.toULongOrNull(): ULong?
fun String.toULongOrNull(radix: Int): ULong?
JVM
1.0

toUpperCase

Returns a copy of this string converted to upper case using the rules of the specified locale.

fun String.toUpperCase(locale: Locale): String
Common
JVM
JS
Native
1.5

toUShort

Parses the string as a UShort number and returns the result.

fun String.toUShort(): UShort
fun String.toUShort(radix: Int): UShort
Common
JVM
JS
Native
1.5

toUShortOrNull

Parses the string as an UShort number and returns the result or null if the string is not a valid representation of a number.

fun String.toUShortOrNull(): UShort?
fun String.toUShortOrNull(radix: Int): UShort?
Common
JVM
JS
Native
1.0

trim

Returns a string having leading and trailing characters matching the predicate removed.

fun String.trim(predicate: (Char) -> Boolean): String

Returns a string having leading and trailing characters from the chars array removed.

fun String.trim(vararg chars: Char): String

Returns a string having leading and trailing whitespace removed.

fun String.trim(): String
Common
JVM
JS
Native
1.0

trimEnd

Returns a string having trailing characters matching the predicate removed.

fun String.trimEnd(predicate: (Char) -> Boolean): String

Returns a string having trailing characters from the chars array removed.

fun String.trimEnd(vararg chars: Char): String

Returns a string having trailing whitespace removed.

fun String.trimEnd(): String
Common
JVM
JS
Native
1.0

trimIndent

Detects a common minimal indent of all the input lines, removes it from every line and also removes the first and the last lines if they are blank (notice difference blank vs empty).

fun String.trimIndent(): String
Common
JVM
JS
Native
1.0

trimMargin

Trims leading whitespace characters followed by marginPrefix from every line of a source string and removes the first and the last lines if they are blank (notice difference blank vs empty).

fun String.trimMargin(marginPrefix: String = "|"): String
Common
JVM
JS
Native
1.0

trimStart

Returns a string having leading characters matching the predicate removed.

fun String.trimStart(predicate: (Char) -> Boolean): String

Returns a string having leading characters from the chars array removed.

fun String.trimStart(vararg chars: Char): String

Returns a string having leading whitespace removed.

fun String.trimStart(): String
JVM
1.5

uppercase

Returns a copy of this string converted to upper case using the rules of the specified locale.

fun String.uppercase(locale: Locale): String
Common
JVM
JS
Native
1.2

windowed

Returns a list of snapshots of the window of the given size sliding along this char sequence with the given step, where each snapshot is a string.

fun CharSequence.windowed(
    size: Int,
    step: Int = 1,
    partialWindows: Boolean = false
): List<String>

Returns a list of results of applying the given transform function to an each char sequence representing a view over the window of the given size sliding along this char sequence with the given step.

fun <R> CharSequence.windowed(
    size: Int,
    step: Int = 1,
    partialWindows: Boolean = false,
    transform: (CharSequence) -> R
): List<R>
Common
JVM
JS
Native
1.2

windowedSequence

Returns a sequence of snapshots of the window of the given size sliding along this char sequence with the given step, where each snapshot is a string.

fun CharSequence.windowedSequence(
    size: Int,
    step: Int = 1,
    partialWindows: Boolean = false
): Sequence<String>

Returns a sequence of results of applying the given transform function to an each char sequence representing a view over the window of the given size sliding along this char sequence with the given step.

fun <R> CharSequence.windowedSequence(
    size: Int,
    step: Int = 1,
    partialWindows: Boolean = false,
    transform: (CharSequence) -> R
): Sequence<R>
Common
JVM
JS
Native
1.0

withIndex

Returns a lazy Iterable that wraps each character of the original char sequence into an IndexedValue containing the index of that character and the character itself.

fun CharSequence.withIndex(): Iterable<IndexedValue<Char>>
Common
JVM
JS
Native
1.0

zip

Returns a list of pairs built from the characters of this and the other char sequences with the same index The returned list has length of the shortest char sequence.

infix fun CharSequence.zip(
    other: CharSequence
): List<Pair<Char, Char>>

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

fun <V> CharSequence.zip(
    other: CharSequence,
    transform: (a: Char, b: Char) -> V
): List<V>
Common
JVM
JS
Native
1.2

zipWithNext

Returns a list of pairs of each two adjacent characters in this char sequence.

fun CharSequence.zipWithNext(): List<Pair<Char, Char>>

Returns a list containing the results of applying the given transform function to an each pair of two adjacent characters in this char sequence.

fun <R> CharSequence.zipWithNext(
    transform: (a: Char, b: Char) -> R
): List<R>

Companion Object Extension Functions

JVM
1.0

format

Uses the provided format as a format string and returns a string obtained by substituting format specifiers in the format string with the provided arguments, using the default locale.

fun String.Companion.format(
    format: String,
    vararg args: Any?
): String

Uses the provided format as a format string and returns a string obtained by substituting format specifiers in the format string with the provided arguments, using the specified locale. If locale is null then no localization is applied.

fun String.Companion.format(
    locale: Locale?,
    format: String,
    vararg args: Any?
): String