An object to which char sequences and values can be appended.

interface Appendable

typealias Appendable = Appendable

Represents the character general category in the Unicode specification.

enum class CharCategory

Represents the Unicode directionality of a character. Character directionality is used to calculate the visual ordering of text.

enum class CharDirectionality

Constant definitions for the standard charsets. These charsets are guaranteed to be available on every implementation of the Java platform.

object Charsets

Represents the results from a single capturing group within a MatchResult of Regex.

class MatchGroup

data class MatchGroup

Represents a collection of captured groups in a single match of a regular expression.

interface MatchGroupCollection : Collection<MatchGroup?>

Extends MatchGroupCollection by introducing a way to get matched groups by name, when regex supports it.

interface MatchNamedGroupCollection : MatchGroupCollection

Represents the results from a single regular expression match.

interface MatchResult

Represents a compiled regular expression. Provides functions to match strings in text with a pattern, replace the found occurrences and split text around matches.

class Regex

class Regex : Serializable

Provides enumeration values to use to set regular expression options.

enum class RegexOption

enum class RegexOption : FlagEnum

A mutable sequence of characters.

class StringBuilder : Appendable, CharSequence

typealias StringBuilder = StringBuilder

class StringBuilder : CharSequence, Appendable

Defines names for Unicode symbols used in proper Typography.

object Typography

The exception thrown when a character encoding or decoding error occurs.

open class CharacterCodingException : Exception

typealias CharacterCodingException = CharacterCodingException

Returns a value indicating a character's general category.

val Char.category: CharCategory

Returns the Unicode directionality property for the given character.

val Char.directionality: CharDirectionality

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

val CharSequence.indices: IntRange

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

val CharSequence.lastIndex: Int

Returns true if all characters match the given predicate.

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

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

Appends all arguments to the given Appendable.

fun <T : Appendable> T.append(vararg value: CharSequence?): T

Appends all arguments to the given StringBuilder.

fun StringBuilder.append(
    vararg value: String?
): StringBuilder

fun StringBuilder.append(vararg value: Any?): StringBuilder

Appends a line feed character (\n) to this Appendable.

fun Appendable.appendLine(): Appendable

Appends value to the given Appendable and a line feed character (\n) after it.

fun Appendable.appendLine(value: CharSequence?): Appendable

fun Appendable.appendLine(value: Char): Appendable

Appends a line feed character (\n) to this StringBuilder.

fun StringBuilder.appendLine(): StringBuilder

Appends value to this StringBuilder, followed by a line feed character (\n).

fun StringBuilder.appendLine(
    value: CharSequence?
): StringBuilder

fun StringBuilder.appendLine(value: String?): StringBuilder

fun StringBuilder.appendLine(value: Any?): StringBuilder

fun StringBuilder.appendLine(value: CharArray): StringBuilder

fun StringBuilder.appendLine(value: Char): StringBuilder

fun StringBuilder.appendLine(value: Boolean): StringBuilder

fun StringBuilder.appendLine(value: Byte): StringBuilder

fun StringBuilder.appendLine(value: Short): StringBuilder

fun StringBuilder.appendLine(value: Int): StringBuilder

fun StringBuilder.appendLine(value: Long): StringBuilder

fun StringBuilder.appendLine(value: Float): StringBuilder

fun StringBuilder.appendLine(value: Double): StringBuilder

Appends a subsequence of the specified character sequence value to this Appendable and returns this instance.

fun <T : Appendable> T.appendRange(
    value: CharSequence, 
    startIndex: Int, 
    endIndex: Int
): T

Appends characters in a subarray of the specified character array value to this string builder and returns this instance.

fun StringBuilder.appendRange(
    value: CharArray, 
    startIndex: Int, 
    endIndex: Int
): StringBuilder

Appends a subsequence of the specified character sequence value to this string builder and returns this instance.

fun StringBuilder.appendRange(
    value: CharSequence, 
    startIndex: Int, 
    endIndex: Int
): StringBuilder

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

fun CharSequence.asIterable(): Iterable<Char>

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

fun CharSequence.asSequence(): Sequence<Char>

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>

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>

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

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

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>

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

Builds new string by populating newly created StringBuilder using provided builderAction and then converting it to String.

fun buildString(
    builderAction: StringBuilder.() -> Unit
): String

Builds new string by populating newly created StringBuilder initialized with the given capacity using provided builderAction and then converting it to String.

fun buildString(
    capacity: Int, 
    builderAction: StringBuilder.() -> Unit
): String

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

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

fun String.capitalize(): String

Returns a named charset with the given charsetName name.

fun charset(charsetName: String): Charset

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>

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>

Clears the content of this string builder making it empty and returns this instance.

fun StringBuilder.clear(): StringBuilder

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

fun String.codePointAt(index: Int): Int

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

fun String.codePointBefore(index: Int): Int

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

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

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

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

Compares two strings lexicographically, optionally ignoring case differences.

fun String.compareTo(
    other: String, 
    ignoreCase: Boolean = false
): Int

fun String.compareTo(other: String, ignoreCase: Boolean): Int

Concatenates characters in this CharArray into a String.

fun CharArray.concatToString(): String

Concatenates characters in this CharArray or its subrange into a String.

fun CharArray.concatToString(
    startIndex: Int = 0, 
    endIndex: Int = this.size
): String

fun CharArray.concatToString(
    startIndex: Int, 
    endIndex: Int
): String

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

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

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

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

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

fun String.decapitalize(): String

Decodes a string from the bytes in UTF-8 encoding in this array.

fun ByteArray.decodeToString(): String

Decodes a string from the bytes in UTF-8 encoding in this array or its subrange.

fun ByteArray.decodeToString(
    startIndex: Int = 0, 
    endIndex: Int = this.size, 
    throwOnInvalidSequence: Boolean = false
): String

fun ByteArray.decodeToString(
    startIndex: Int, 
    endIndex: Int, 
    throwOnInvalidSequence: Boolean
): String

Removes the character at the specified index from this string builder and returns this instance.

fun StringBuilder.deleteAt(index: Int): StringBuilder

Removes the character at the specified index from this string builder and returns this instance.

fun StringBuilder.deleteCharAt(index: Int): StringBuilder

Removes characters in the specified range from this string builder and returns this instance.

fun StringBuilder.deleteRange(
    startIndex: Int, 
    endIndex: Int
): StringBuilder

Returns a subsequence of this char sequence with the first n characters removed.

fun CharSequence.drop(n: Int): CharSequence

Returns a string with the first n characters removed.

fun String.drop(n: Int): String

Returns a subsequence of this char sequence with the last n characters removed.

fun CharSequence.dropLast(n: Int): CharSequence

Returns a string with the last n characters removed.

fun String.dropLast(n: Int): String

Returns a subsequence of this char sequence containing all characters except last characters that satisfy the given predicate.

fun CharSequence.dropLastWhile(
    predicate: (Char) -> Boolean
): CharSequence

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

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

Returns a subsequence of this char sequence containing all characters except first characters that satisfy the given predicate.

fun CharSequence.dropWhile(
    predicate: (Char) -> Boolean
): CharSequence

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

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

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

fun CharSequence.elementAt(index: Int): Char

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

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?

Encodes this string to an array of bytes in UTF-8 encoding.

fun String.encodeToByteArray(): ByteArray

Encodes this string or its substring to an array of bytes in UTF-8 encoding.

fun String.encodeToByteArray(
    startIndex: Int = 0, 
    endIndex: Int = this.length, 
    throwOnInvalidSequence: Boolean = false
): ByteArray

fun String.encodeToByteArray(
    startIndex: Int, 
    endIndex: Int, 
    throwOnInvalidSequence: Boolean
): ByteArray

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

Returns true if this string ends with the specified suffix.

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

fun String.endsWith(
    suffix: String, 
    ignoreCase: Boolean
): Boolean

Returns true if this character is equal to the other character, optionally ignoring character case.

fun Char.equals(
    other: Char, 
    ignoreCase: Boolean = false
): Boolean

Returns true if this string is equal to other, optionally ignoring character case.

fun String?.equals(
    other: String?, 
    ignoreCase: Boolean = false
): Boolean

fun String?.equals(
    other: String?, 
    ignoreCase: Boolean
): Boolean

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

fun CharSequence.filter(
    predicate: (Char) -> Boolean
): CharSequence

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

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

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

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

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

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

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

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

fun CharSequence.filterNot(
    predicate: (Char) -> Boolean
): CharSequence

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

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

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

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

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

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

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

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>?

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

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

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>?

Returns first character.

fun CharSequence.first(): Char

Returns the first character matching the given predicate.

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

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?

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>

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>

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

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

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

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

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

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

Performs the given action on each character.

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

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

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

Uses this string as a format string and returns a string obtained by substituting the specified 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 the specified arguments, using the specified locale.

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

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

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

Returns a named group with the specified name.

operator fun MatchGroupCollection.get(
    name: String
): MatchGroup?

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

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?

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>>

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

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>

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

fun CharSequence.hasSurrogatePairAt(index: Int): Boolean

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

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

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

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

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

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

Inserts characters in a subsequence of the specified character sequence csq into this string builder at the specified index and returns this instance.

fun StringBuilder.insert(
    index: Int, 
    csq: CharSequence?, 
    start: Int, 
    end: Int
): StringBuilder

Inserts characters in a subarray of the specified character array value into this string builder at the specified index and returns this instance.

fun StringBuilder.insertRange(
    index: Int, 
    value: CharArray, 
    startIndex: Int, 
    endIndex: Int
): StringBuilder

Inserts characters in a subsequence of the specified character sequence value into this string builder at the specified index and returns this instance.

fun StringBuilder.insertRange(
    index: Int, 
    value: CharSequence, 
    startIndex: Int, 
    endIndex: Int
): StringBuilder

Returns a canonical representation for this string object.

fun String.intern(): String

Returns true if this string is empty or consists solely of whitespace characters.

fun CharSequence.isBlank(): Boolean

Returns true if this character (Unicode code point) is defined in Unicode.

fun Char.isDefined(): Boolean

Returns true if this character (Unicode code point) is a digit.

fun Char.isDigit(): Boolean

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

fun CharSequence.isEmpty(): Boolean

Returns true if this character is a Unicode high-surrogate code unit (also known as leading-surrogate code unit).

fun Char.isHighSurrogate(): Boolean

Returns true if this character (Unicode code point) should be regarded as an ignorable character in a Java identifier or a Unicode identifier.

fun Char.isIdentifierIgnorable(): Boolean

Returns true if this character is an ISO control character.

fun Char.isISOControl(): Boolean

Returns true if this character (Unicode code point) may be part of a Java identifier as other than the first character.

fun Char.isJavaIdentifierPart(): Boolean

Returns true if this character is permissible as the first character in a Java identifier.

fun Char.isJavaIdentifierStart(): Boolean

Returns true if this character is a letter.

fun Char.isLetter(): Boolean

Returns true if this character is a letter or digit.

fun Char.isLetterOrDigit(): Boolean

Returns true if this character is lower case.

fun Char.isLowerCase(): Boolean

Returns true if this character is a Unicode low-surrogate code unit (also known as trailing-surrogate code unit).

fun Char.isLowSurrogate(): Boolean

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

fun CharSequence.isNotBlank(): Boolean

Returns true if this char sequence is not empty.

fun CharSequence.isNotEmpty(): Boolean

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

fun CharSequence?.isNullOrBlank(): Boolean

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

fun CharSequence?.isNullOrEmpty(): Boolean

Returns true if this character is a Unicode surrogate code unit.

fun Char.isSurrogate(): Boolean

Returns true if this character is a titlecase character.

fun Char.isTitleCase(): Boolean

Returns true if this character is upper case.

fun Char.isUpperCase(): Boolean

Determines whether a character is whitespace according to the Unicode standard. Returns true if the character is whitespace.

fun Char.isWhitespace(): Boolean

Iterator for characters of the given char sequence.

operator fun CharSequence.iterator(): CharIterator

Returns the last character.

fun CharSequence.last(): Char

Returns the last character matching the given predicate.

fun CharSequence.last(predicate: (Char) -> Boolean): Char

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

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

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?

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>

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>

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>

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>

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>

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

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

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>

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

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

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

infix fun CharSequence.matches(regex: Regex): Boolean

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?

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

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?

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

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?

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

fun CharSequence.maxOrNull(): Char?

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?

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?

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

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?

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

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?

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

fun CharSequence.minOrNull(): Char?

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?

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

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

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

fun <S : CharSequence> S.onEach(action: (Char) -> Unit): S

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

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

fun String?.orEmpty(): String

Returns a char sequence with content of this char sequence padded at the end to the specified length with the specified character or space.

fun CharSequence.padEnd(
    length: Int, 
    padChar: Char = ' '
): CharSequence

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

fun String.padEnd(length: Int, padChar: Char = ' '): String

Returns a char sequence with content of this char sequence padded at the beginning to the specified length with the specified character or space.

fun CharSequence.padStart(
    length: Int, 
    padChar: Char = ' '
): CharSequence

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

fun String.padStart(length: Int, padChar: Char = ' '): String

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

fun CharSequence.partition(
    predicate: (Char) -> Boolean
): Pair<CharSequence, CharSequence>

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>

Concatenates this Char and a String.

operator fun Char.plus(other: String): String

Prepends indent to every line of the original string.

fun String.prependIndent(indent: String = "    "): String

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

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?

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

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

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?

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?

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

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

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?

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?

Creates a regular expression from the specified pattern string and the specified single option.

fun Regex_0(pattern: String, option: RegexOption): Regex

Creates a regular expression from the specified pattern string and the default options.

fun Regex_1(pattern: String): Regex

Returns true if the specified range in this char sequence is equal to the specified range in another char sequence.

fun CharSequence.regionMatches(
    thisOffset: Int, 
    other: CharSequence, 
    otherOffset: Int, 
    length: Int, 
    ignoreCase: Boolean = false
): Boolean

fun CharSequence.regionMatches(
    thisOffset: Int, 
    other: CharSequence, 
    otherOffset: Int, 
    length: Int, 
    ignoreCase: Boolean
): Boolean

Returns true if the specified range in this string is equal to the specified range in another string.

fun String.regionMatches(
    thisOffset: Int, 
    other: String, 
    otherOffset: Int, 
    length: Int, 
    ignoreCase: Boolean = false
): Boolean

If this char sequence starts with the given prefix, returns a new char sequence with the prefix removed. Otherwise, returns a new char sequence with the same characters.

fun CharSequence.removePrefix(
    prefix: CharSequence
): CharSequence

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

Returns a char sequence with content of this char sequence where its part at the given range is removed.

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

Removes the part of a string at a given range.

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

Returns a char sequence with content of this char sequence where its part at the given range is removed.

fun CharSequence.removeRange(range: IntRange): CharSequence

Removes the part of a string at the given range.

fun String.removeRange(range: IntRange): String

If this char sequence ends with the given suffix, returns a new char sequence with the suffix removed. Otherwise, returns a new char sequence with the same characters.

fun CharSequence.removeSuffix(
    suffix: CharSequence
): CharSequence

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

When this char sequence starts with the given prefix and ends with the given suffix, returns a new char sequence having both the given prefix and suffix removed. Otherwise returns a new char sequence with the same characters.

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

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

When this char sequence starts with and ends with the given delimiter, returns a new char sequence having this delimiter removed both from the start and end. Otherwise returns a new char sequence with the same characters.

fun CharSequence.removeSurrounding(
    delimiter: CharSequence
): CharSequence

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

Returns a string containing this char sequence repeated n times.

fun CharSequence.repeat(n: Int): String

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

Returns a new string with all occurrences of oldChar replaced with newChar.

fun String.replace(
    oldChar: Char, 
    newChar: Char, 
    ignoreCase: Boolean = false
): String

fun String.replace(
    oldChar: Char, 
    newChar: Char, 
    ignoreCase: Boolean
): String

Returns a new string obtained by replacing all occurrences of the oldValue substring in this string with the specified newValue string.

fun String.replace(
    oldValue: String, 
    newValue: String, 
    ignoreCase: Boolean = false
): String

fun String.replace(
    oldValue: String, 
    newValue: String, 
    ignoreCase: Boolean
): String

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

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

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

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

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

Returns a new string with the first occurrence of oldChar replaced with newChar.

fun String.replaceFirst(
    oldChar: Char, 
    newChar: Char, 
    ignoreCase: Boolean = false
): String

fun String.replaceFirst(
    oldChar: Char, 
    newChar: Char, 
    ignoreCase: Boolean
): String

Returns a new string obtained by replacing the first occurrence of the oldValue substring in this string with the specified newValue string.

fun String.replaceFirst(
    oldValue: String, 
    newValue: String, 
    ignoreCase: Boolean = false
): String

fun String.replaceFirst(
    oldValue: String, 
    newValue: String, 
    ignoreCase: Boolean
): String

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

fun String.replaceIndent(newIndent: String = ""): String

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

fun String.replaceIndentByMargin(
    newIndent: String = "", 
    marginPrefix: String = "|"
): String

Returns a char sequence with content of this char sequence where its part at the given range is replaced with the replacement char sequence.

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

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

Returns a char sequence with content of this char sequence where its part at the given range is replaced with the replacement char sequence.

fun CharSequence.replaceRange(
    range: IntRange, 
    replacement: CharSequence
): CharSequence

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

fun String.replaceRange(
    range: IntRange, 
    replacement: CharSequence
): String

Returns a char sequence with characters in reversed order.

fun CharSequence.reversed(): CharSequence

Returns a string with characters in reversed order.

fun String.reversed(): String

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>

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>

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>

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>

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>

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>

Sets the character at the specified index to the specified value.

operator fun StringBuilder.set(index: Int, value: Char)

Replaces characters in the specified range of this string builder with characters in the specified string value and returns this instance.

fun StringBuilder.setRange(
    startIndex: Int, 
    endIndex: Int, 
    value: String
): StringBuilder

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

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?

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

fun CharSequence.slice(indices: IntRange): CharSequence

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

fun String.slice(indices: IntRange): String

Returns a char sequence containing characters of the original char sequence at specified indices.

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

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

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

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>

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

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

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

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>

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

Returns true if this string starts with the specified prefix.

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

fun String.startsWith(
    prefix: String, 
    ignoreCase: Boolean
): Boolean

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

fun String.startsWith(
    prefix: String, 
    startIndex: Int, 
    ignoreCase: Boolean = false
): Boolean

fun String.startsWith(
    prefix: String, 
    startIndex: Int, 
    ignoreCase: Boolean
): Boolean

Converts the data from a portion of the specified array of bytes to characters using the specified character set and returns the conversion result as a string.

fun String(
    bytes: ByteArray, 
    offset: Int, 
    length: Int, 
    charset: Charset
): String

Converts the data from the specified array of bytes to characters using the specified character set and returns the conversion result as a string.

fun String(bytes: ByteArray, charset: Charset): String

Converts the data from a portion of the specified array of bytes to characters using the UTF-8 character set and returns the conversion result as a string.

fun String(
    bytes: ByteArray, 
    offset: Int, 
    length: Int
): String

Converts the data from the specified array of bytes to characters using the UTF-8 character set and returns the conversion result as a string.

fun String(bytes: ByteArray): String

Converts the code points from a portion of the specified Unicode code point array to a string.

fun String(
    codePoints: IntArray, 
    offset: Int, 
    length: Int
): String

Converts the contents of the specified StringBuffer to a string.

fun String(stringBuffer: StringBuffer): String

Converts the contents of the specified StringBuilder to a string.

fun String(stringBuilder: StringBuilder): String

Converts the characters in the specified array to a string.

fun String(chars: CharArray): String

fun String(chars: CharArray): String

Converts the characters from a portion of the specified array to a string.

fun String(
    chars: CharArray, 
    offset: Int, 
    length: Int
): String

fun String(
    chars: CharArray, 
    offset: Int, 
    length: Int
): String

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

fun CharSequence.subSequence(range: IntRange): CharSequence

Returns a subsequence of this char sequence.

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

Returns a substring specified by the given range of indices.

fun String.substring(range: IntRange): String

Returns a substring of chars from a range of this char sequence starting at the startIndex and ending right before the endIndex.

fun CharSequence.substring(
    startIndex: Int, 
    endIndex: Int = length
): String

Returns a substring of chars at indices from the specified range of this char sequence.

fun CharSequence.substring(range: IntRange): String

Returns a substring of this string that starts at the specified startIndex and continues to the end of the string.

fun String.substring(startIndex: Int): String

Returns the substring of this string starting at the startIndex and ending right before the endIndex.

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

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

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

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

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

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

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

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

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

fun CharSequence.sumOf(selector: (Char) -> Int): Int

fun CharSequence.sumOf(selector: (Char) -> Long): Long

fun CharSequence.sumOf(selector: (Char) -> UInt): UInt

fun CharSequence.sumOf(selector: (Char) -> ULong): ULong

fun CharSequence.sumOf(
    selector: (Char) -> BigDecimal
): BigDecimal

fun CharSequence.sumOf(
    selector: (Char) -> BigInteger
): BigInteger

Returns a subsequence of this char sequence containing the first n characters from this char sequence, or the entire char sequence if this char sequence is shorter.

fun CharSequence.take(n: Int): CharSequence

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

Returns a subsequence of this char sequence containing the last n characters from this char sequence, or the entire char sequence if this char sequence is shorter.

fun CharSequence.takeLast(n: Int): CharSequence

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

Returns a subsequence of this char sequence containing last characters that satisfy the given predicate.

fun CharSequence.takeLastWhile(
    predicate: (Char) -> Boolean
): CharSequence

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

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

Returns a subsequence of this char sequence containing the first characters that satisfy the given predicate.

fun CharSequence.takeWhile(
    predicate: (Char) -> Boolean
): CharSequence

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

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

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

fun String.toBigDecimal(): BigDecimal

fun String.toBigDecimal(mathContext: MathContext): BigDecimal

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?

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

fun String.toBigInteger(): BigInteger

fun String.toBigInteger(radix: Int): BigInteger

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?

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

fun String.toBoolean(): Boolean

Returns true if this string is not null and its content is equal to the word "true", ignoring case, and false otherwise.

fun String?.toBoolean(): Boolean

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

fun String.toByte(): Byte

fun String.toByte(radix: Int): Byte

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

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?

Copies characters from this string into the destination character array and returns that array.

fun String.toCharArray(
    destination: CharArray, 
    destinationOffset: Int = 0, 
    startIndex: Int = 0, 
    endIndex: Int = length
): CharArray

Returns a CharArray containing characters of this string.

fun String.toCharArray(): CharArray

Returns a CharArray containing characters of this string or its substring.

fun String.toCharArray(
    startIndex: Int = 0, 
    endIndex: Int = this.length
): CharArray

fun String.toCharArray(
    startIndex: Int, 
    endIndex: Int
): CharArray

Copies characters from this string builder into the destination character array.

fun StringBuilder.toCharArray(
    destination: CharArray, 
    destinationOffset: Int = 0, 
    startIndex: Int = 0, 
    endIndex: Int = this.length)

Appends all characters to the given destination collection.

fun <C : MutableCollection<in Char>> CharSequence.toCollection(
    destination: C
): C

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

fun String.toDouble(): Double

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

fun String.toDoubleOrNull(): Double?

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

fun String.toFloat(): Float

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

fun String.toFloatOrNull(): Float?

Returns a new HashSet of all characters.

fun CharSequence.toHashSet(): HashSet<Char>

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

fun String.toInt(): Int

fun String.toInt(radix: Int): Int

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?

Returns a List containing all characters.

fun CharSequence.toList(): List<Char>

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

fun String.toLong(): Long

fun String.toLong(radix: Int): Long

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?

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

fun String.toLowerCase(locale: Locale): String

Converts this character to lowercase.

fun Char.toLowerCase(): Char

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

fun String.toLowerCase(): String

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

fun CharSequence.toMutableList(): MutableList<Char>

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

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

Returns a Set of all characters.

fun CharSequence.toSet(): Set<Char>

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

fun String.toShort(): Short

fun String.toShort(radix: Int): Short

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?

Returns a new SortedSet of all characters.

fun CharSequence.toSortedSet(): SortedSet<Char>

Returns a string representation of this Byte value in the specified radix.

fun UByte.toString(radix: Int): String

fun Byte.toString(radix: Int): String

Returns a string representation of this Short value in the specified radix.

fun UShort.toString(radix: Int): String

fun Short.toString(radix: Int): String

Returns a string representation of this Int value in the specified radix.

fun UInt.toString(radix: Int): String

fun Int.toString(radix: Int): String

Returns a string representation of this Long value in the specified radix.

fun ULong.toString(radix: Int): String

fun Long.toString(radix: Int): String

Converts this character to titlecase.

fun Char.toTitleCase(): Char

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

fun String.toUByte(): UByte

fun String.toUByte(radix: Int): UByte

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?

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

fun String.toUInt(): UInt

fun String.toUInt(radix: Int): UInt

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?

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

fun String.toULong(): ULong

fun String.toULong(radix: Int): ULong

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?

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

fun String.toUpperCase(locale: Locale): String

Converts this character to uppercase.

fun Char.toUpperCase(): Char

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

fun String.toUpperCase(): String

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

fun String.toUShort(): UShort

fun String.toUShort(radix: Int): UShort

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?

Returns a sub sequence of this char sequence having leading and trailing characters matching the predicate removed.

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

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

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

Returns a sub sequence of this char sequence having leading and trailing characters from the chars array removed.

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

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

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

Returns a sub sequence of this char sequence having leading and trailing whitespace removed.

fun CharSequence.trim(): CharSequence

Returns a string having leading and trailing whitespace removed.

fun String.trim(): String

Returns a sub sequence of this char sequence having trailing characters matching the predicate removed.

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

Returns a string having trailing characters matching the predicate removed.

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

Returns a sub sequence of this char sequence having trailing characters from the chars array removed.

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

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

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

Returns a sub sequence of this char sequence having trailing whitespace removed.

fun CharSequence.trimEnd(): CharSequence

Returns a string having trailing whitespace removed.

fun String.trimEnd(): String

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

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

Returns a sub sequence of this char sequence having leading characters matching the predicate removed.

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

Returns a string having leading characters matching the predicate removed.

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

Returns a sub sequence of this char sequence having leading characters from the chars array removed.

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

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

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

Returns a sub sequence of this char sequence having leading whitespace removed.

fun CharSequence.trimStart(): CharSequence

Returns a string having leading whitespace removed.

fun String.trimStart(): String

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>

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>

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>>

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>

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>

A Comparator that orders strings ignoring character case.

val String.Companion.CASE_INSENSITIVE_ORDER: Comparator<String>

Uses the provided format as a format string and returns a string obtained by substituting the specified 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 the specified arguments, using the specified locale.

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

Uses the provided format as a format string and returns a string obtained by substituting the specified 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

Checks if the codepoint specified is a supplementary codepoint or not.

fun Char.Companion.isSupplementaryCodePoint(
    codepoint: Int
): Boolean

Converts the codepoint specified to a char array. If the codepoint is not supplementary, the method will return an array with one element otherwise it will return an array A with a high surrogate in A0 and a low surrogate in A1.

fun Char.Companion.toChars(codePoint: Int): CharArray

Converts a surrogate pair to a unicode code point. Doesn't validate that the characters are a valid surrogate pair.

fun Char.Companion.toCodePoint(high: Char, low: Char): Int