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Kotlin Standard Library for JVM
/*
* Copyright 2010-2020 JetBrains s.r.o. and Kotlin Programming Language contributors.
* Use of this source code is governed by the Apache 2.0 license that can be found in the license/LICENSE.txt file.
*/
@file:kotlin.jvm.JvmMultifileClass
@file:kotlin.jvm.JvmName("StringsKt")
@file:Suppress("PLATFORM_CLASS_MAPPED_TO_KOTLIN")
package kotlin.text
import java.nio.ByteBuffer
import java.nio.CharBuffer
import java.nio.charset.Charset
import java.nio.charset.CodingErrorAction
import java.util.Locale
import java.util.regex.Pattern
/**
* Returns the index within this string of the first occurrence of the specified character, starting from the specified offset.
*/
@kotlin.internal.InlineOnly
internal actual inline fun String.nativeIndexOf(ch: Char, fromIndex: Int): Int = (this as java.lang.String).indexOf(ch.toInt(), fromIndex)
/**
* Returns the index within this string of the first occurrence of the specified substring, starting from the specified offset.
*/
@kotlin.internal.InlineOnly
internal actual inline fun String.nativeIndexOf(str: String, fromIndex: Int): Int = (this as java.lang.String).indexOf(str, fromIndex)
/**
* Returns the index within this string of the last occurrence of the specified character.
*/
@kotlin.internal.InlineOnly
internal actual inline fun String.nativeLastIndexOf(ch: Char, fromIndex: Int): Int = (this as java.lang.String).lastIndexOf(ch.toInt(), fromIndex)
/**
* Returns the index within this string of the last occurrence of the specified character, starting from the specified offset.
*/
@kotlin.internal.InlineOnly
internal actual inline fun String.nativeLastIndexOf(str: String, fromIndex: Int): Int = (this as java.lang.String).lastIndexOf(str, fromIndex)
/**
* Returns `true` if this string is equal to [other], optionally ignoring character case.
*
* @param ignoreCase `true` to ignore character case when comparing strings. By default `false`.
*/
@Suppress("ACTUAL_FUNCTION_WITH_DEFAULT_ARGUMENTS")
public actual fun String?.equals(other: String?, ignoreCase: Boolean = false): Boolean {
if (this === null)
return other === null
return if (!ignoreCase)
(this as java.lang.String).equals(other)
else
(this as java.lang.String).equalsIgnoreCase(other)
}
/**
* Returns a new string with all occurrences of [oldChar] replaced with [newChar].
*/
@Suppress("ACTUAL_FUNCTION_WITH_DEFAULT_ARGUMENTS")
public actual fun String.replace(oldChar: Char, newChar: Char, ignoreCase: Boolean = false): String {
if (!ignoreCase)
return (this as java.lang.String).replace(oldChar, newChar)
else
return splitToSequence(oldChar, ignoreCase = ignoreCase).joinToString(separator = newChar.toString())
}
/**
* Returns a new string obtained by replacing all occurrences of the [oldValue] substring in this string
* with the specified [newValue] string.
*/
@Suppress("ACTUAL_FUNCTION_WITH_DEFAULT_ARGUMENTS")
public actual fun String.replace(oldValue: String, newValue: String, ignoreCase: Boolean = false): String =
splitToSequence(oldValue, ignoreCase = ignoreCase).joinToString(separator = newValue)
/**
* Returns a new string with the first occurrence of [oldChar] replaced with [newChar].
*/
@Suppress("ACTUAL_FUNCTION_WITH_DEFAULT_ARGUMENTS")
public actual fun String.replaceFirst(oldChar: Char, newChar: Char, ignoreCase: Boolean = false): String {
val index = indexOf(oldChar, ignoreCase = ignoreCase)
return if (index < 0) this else this.replaceRange(index, index + 1, newChar.toString())
}
/**
* Returns a new string obtained by replacing the first occurrence of the [oldValue] substring in this string
* with the specified [newValue] string.
*/
@Suppress("ACTUAL_FUNCTION_WITH_DEFAULT_ARGUMENTS")
public actual fun String.replaceFirst(oldValue: String, newValue: String, ignoreCase: Boolean = false): String {
val index = indexOf(oldValue, ignoreCase = ignoreCase)
return if (index < 0) this else this.replaceRange(index, index + oldValue.length, newValue)
}
/**
* Returns a copy of this string converted to upper case using the rules of the default locale.
*
* @sample samples.text.Strings.toUpperCase
*/
@kotlin.internal.InlineOnly
public actual inline fun String.toUpperCase(): String = (this as java.lang.String).toUpperCase()
/**
* Returns a copy of this string converted to lower case using the rules of the default locale.
*
* @sample samples.text.Strings.toLowerCase
*/
@kotlin.internal.InlineOnly
public actual inline fun String.toLowerCase(): String = (this as java.lang.String).toLowerCase()
/**
* Concatenates characters in this [CharArray] into a String.
*/
@SinceKotlin("1.4")
@WasExperimental(ExperimentalStdlibApi::class)
public actual fun CharArray.concatToString(): String {
return String(this)
}
/**
* Concatenates characters in this [CharArray] or its subrange into a String.
*
* @param startIndex the beginning (inclusive) of the subrange of characters, 0 by default.
* @param endIndex the end (exclusive) of the subrange of characters, size of this array by default.
*
* @throws IndexOutOfBoundsException if [startIndex] is less than zero or [endIndex] is greater than the size of this array.
* @throws IllegalArgumentException if [startIndex] is greater than [endIndex].
*/
@SinceKotlin("1.4")
@WasExperimental(ExperimentalStdlibApi::class)
@Suppress("ACTUAL_FUNCTION_WITH_DEFAULT_ARGUMENTS")
public actual fun CharArray.concatToString(startIndex: Int = 0, endIndex: Int = this.size): String {
AbstractList.checkBoundsIndexes(startIndex, endIndex, this.size)
return String(this, startIndex, endIndex - startIndex)
}
/**
* Returns a [CharArray] containing characters of this string or its substring.
*
* @param startIndex the beginning (inclusive) of the substring, 0 by default.
* @param endIndex the end (exclusive) of the substring, length of this string by default.
*
* @throws IndexOutOfBoundsException if [startIndex] is less than zero or [endIndex] is greater than the length of this string.
* @throws IllegalArgumentException if [startIndex] is greater than [endIndex].
*/
@SinceKotlin("1.4")
@WasExperimental(ExperimentalStdlibApi::class)
@Suppress("ACTUAL_FUNCTION_WITH_DEFAULT_ARGUMENTS")
public actual fun String.toCharArray(startIndex: Int = 0, endIndex: Int = this.length): CharArray {
AbstractList.checkBoundsIndexes(startIndex, endIndex, length)
return toCharArray(CharArray(endIndex - startIndex), 0, startIndex, endIndex)
}
/**
* Decodes a string from the bytes in UTF-8 encoding in this array.
*
* Malformed byte sequences are replaced by the replacement char `\uFFFD`.
*/
@SinceKotlin("1.4")
@WasExperimental(ExperimentalStdlibApi::class)
public actual fun ByteArray.decodeToString(): String {
return String(this)
}
/**
* Decodes a string from the bytes in UTF-8 encoding in this array or its subrange.
*
* @param startIndex the beginning (inclusive) of the subrange to decode, 0 by default.
* @param endIndex the end (exclusive) of the subrange to decode, size of this array by default.
* @param throwOnInvalidSequence specifies whether to throw an exception on malformed byte sequence or replace it by the replacement char `\uFFFD`.
*
* @throws IndexOutOfBoundsException if [startIndex] is less than zero or [endIndex] is greater than the size of this array.
* @throws IllegalArgumentException if [startIndex] is greater than [endIndex].
* @throws CharacterCodingException if the byte array contains malformed UTF-8 byte sequence and [throwOnInvalidSequence] is true.
*/
@SinceKotlin("1.4")
@WasExperimental(ExperimentalStdlibApi::class)
@Suppress("ACTUAL_FUNCTION_WITH_DEFAULT_ARGUMENTS")
public actual fun ByteArray.decodeToString(
startIndex: Int = 0,
endIndex: Int = this.size,
throwOnInvalidSequence: Boolean = false
): String {
AbstractList.checkBoundsIndexes(startIndex, endIndex, this.size)
if (!throwOnInvalidSequence) {
return String(this, startIndex, endIndex - startIndex)
}
val decoder = Charsets.UTF_8.newDecoder()
.onMalformedInput(CodingErrorAction.REPORT)
.onUnmappableCharacter(CodingErrorAction.REPORT)
return decoder.decode(ByteBuffer.wrap(this, startIndex, endIndex - startIndex)).toString()
}
/**
* Encodes this string to an array of bytes in UTF-8 encoding.
*
* Any malformed char sequence is replaced by the replacement byte sequence.
*/
@SinceKotlin("1.4")
@WasExperimental(ExperimentalStdlibApi::class)
public actual fun String.encodeToByteArray(): ByteArray {
return this.toByteArray(Charsets.UTF_8)
}
/**
* Encodes this string or its substring to an array of bytes in UTF-8 encoding.
*
* @param startIndex the beginning (inclusive) of the substring to encode, 0 by default.
* @param endIndex the end (exclusive) of the substring to encode, length of this string by default.
* @param throwOnInvalidSequence specifies whether to throw an exception on malformed char sequence or replace.
*
* @throws IndexOutOfBoundsException if [startIndex] is less than zero or [endIndex] is greater than the length of this string.
* @throws IllegalArgumentException if [startIndex] is greater than [endIndex].
* @throws CharacterCodingException if this string contains malformed char sequence and [throwOnInvalidSequence] is true.
*/
@SinceKotlin("1.4")
@WasExperimental(ExperimentalStdlibApi::class)
@Suppress("ACTUAL_FUNCTION_WITH_DEFAULT_ARGUMENTS")
public actual fun String.encodeToByteArray(
startIndex: Int = 0,
endIndex: Int = this.length,
throwOnInvalidSequence: Boolean = false
): ByteArray {
AbstractList.checkBoundsIndexes(startIndex, endIndex, length)
if (!throwOnInvalidSequence) {
return this.substring(startIndex, endIndex).toByteArray(Charsets.UTF_8)
}
val encoder = Charsets.UTF_8.newEncoder()
.onMalformedInput(CodingErrorAction.REPORT)
.onUnmappableCharacter(CodingErrorAction.REPORT)
val byteBuffer = encoder.encode(CharBuffer.wrap(this, startIndex, endIndex))
return if (byteBuffer.hasArray() && byteBuffer.arrayOffset() == 0 && byteBuffer.remaining() == byteBuffer.array()!!.size) {
byteBuffer.array()
} else {
ByteArray(byteBuffer.remaining()).also { byteBuffer.get(it) }
}
}
/**
* Returns a [CharArray] containing characters of this string.
*/
@kotlin.internal.InlineOnly
public actual inline fun String.toCharArray(): CharArray = (this as java.lang.String).toCharArray()
/**
* Copies characters from this string into the [destination] character array and returns that array.
*
* @param destination the array to copy to.
* @param destinationOffset the position in the array to copy to.
* @param startIndex the start offset (inclusive) of the substring to copy.
* @param endIndex the end offset (exclusive) of the substring to copy.
*/
@kotlin.internal.InlineOnly
public inline fun String.toCharArray(
destination: CharArray,
destinationOffset: Int = 0,
startIndex: Int = 0,
endIndex: Int = length
): CharArray {
(this as java.lang.String).getChars(startIndex, endIndex, destination, destinationOffset)
return destination
}
/**
* Uses this string as a format string and returns a string obtained by substituting the specified arguments,
* using the default locale.
*/
@kotlin.internal.InlineOnly
public inline fun String.format(vararg args: Any?): String = java.lang.String.format(this, *args)
/**
* Uses the provided [format] as a format string and returns a string obtained by substituting the specified arguments,
* using the default locale.
*/
@kotlin.internal.InlineOnly
public inline fun String.Companion.format(format: String, vararg args: Any?): String = java.lang.String.format(format, *args)
/**
* Uses this string as a format string and returns a string obtained by substituting the specified arguments,
* using the specified locale.
*/
@Deprecated("Use Kotlin compiler 1.4 to avoid deprecation warning.")
@DeprecatedSinceKotlin(hiddenSince = "1.4")
@kotlin.internal.InlineOnly
public inline fun String.format(locale: Locale, vararg args: Any?): String = java.lang.String.format(locale, this, *args)
/**
* 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.
*/
@SinceKotlin("1.4")
@JvmName("formatNullable")
@kotlin.internal.InlineOnly
public inline fun String.format(locale: Locale?, vararg args: Any?): String = java.lang.String.format(locale, this, *args)
/**
* Uses the provided [format] as a format string and returns a string obtained by substituting the specified arguments,
* using the specified locale.
*/
@Deprecated("Use Kotlin compiler 1.4 to avoid deprecation warning.")
@DeprecatedSinceKotlin(hiddenSince = "1.4")
@kotlin.internal.InlineOnly
public inline fun String.Companion.format(locale: Locale, format: String, vararg args: Any?): String =
java.lang.String.format(locale, format, *args)
/**
* 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.
*/
@SinceKotlin("1.4")
@JvmName("formatNullable")
@kotlin.internal.InlineOnly
public inline fun String.Companion.format(locale: Locale?, format: String, vararg args: Any?): String =
java.lang.String.format(locale, format, *args)
/**
* Splits this char sequence around matches of the given regular expression.
*
* This function has two notable differences from the method [Pattern.split]:
* - the function returns the result as a `List` rather than an `Array`;
* - when the [limit] is not specified or specified as 0,
* this function doesn't drop trailing empty strings from the result.
* @param limit Non-negative value specifying the maximum number of substrings to return.
* Zero by default means no limit is set.
*/
public fun CharSequence.split(regex: Pattern, limit: Int = 0): List {
require(limit >= 0, { "Limit must be non-negative, but was $limit." })
return regex.split(this, if (limit == 0) -1 else limit).asList()
}
/**
* Returns a substring of this string that starts at the specified [startIndex] and continues to the end of the string.
*/
@kotlin.internal.InlineOnly
public actual inline fun String.substring(startIndex: Int): String = (this as java.lang.String).substring(startIndex)
/**
* Returns the substring of this string starting at the [startIndex] and ending right before the [endIndex].
*
* @param startIndex the start index (inclusive).
* @param endIndex the end index (exclusive).
*/
@kotlin.internal.InlineOnly
public actual inline fun String.substring(startIndex: Int, endIndex: Int): String = (this as java.lang.String).substring(startIndex, endIndex)
/**
* Returns `true` if this string starts with the specified prefix.
*/
@Suppress("ACTUAL_FUNCTION_WITH_DEFAULT_ARGUMENTS")
public actual fun String.startsWith(prefix: String, ignoreCase: Boolean = false): Boolean {
if (!ignoreCase)
return (this as java.lang.String).startsWith(prefix)
else
return regionMatches(0, prefix, 0, prefix.length, ignoreCase)
}
/**
* Returns `true` if a substring of this string starting at the specified offset [startIndex] starts with the specified prefix.
*/
@Suppress("ACTUAL_FUNCTION_WITH_DEFAULT_ARGUMENTS")
public actual fun String.startsWith(prefix: String, startIndex: Int, ignoreCase: Boolean = false): Boolean {
if (!ignoreCase)
return (this as java.lang.String).startsWith(prefix, startIndex)
else
return regionMatches(startIndex, prefix, 0, prefix.length, ignoreCase)
}
/**
* Returns `true` if this string ends with the specified suffix.
*/
@Suppress("ACTUAL_FUNCTION_WITH_DEFAULT_ARGUMENTS")
public actual fun String.endsWith(suffix: String, ignoreCase: Boolean = false): Boolean {
if (!ignoreCase)
return (this as java.lang.String).endsWith(suffix)
else
return regionMatches(length - suffix.length, suffix, 0, suffix.length, ignoreCase = true)
}
// "constructors" for String
/**
* 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.
*
* @param bytes the source array for the conversion.
* @param offset the offset in the array of the data to be converted.
* @param length the number of bytes to be converted.
* @param charset the character set to use.
*/
@kotlin.internal.InlineOnly
public inline fun String(bytes: ByteArray, offset: Int, length: Int, charset: Charset): String =
java.lang.String(bytes, offset, length, charset) as 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.
*/
@kotlin.internal.InlineOnly
public inline fun String(bytes: ByteArray, charset: Charset): String = java.lang.String(bytes, charset) as 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.
*
* @param bytes the source array for the conversion.
* @param offset the offset in the array of the data to be converted.
* @param length the number of bytes to be converted.
*/
@kotlin.internal.InlineOnly
public inline fun String(bytes: ByteArray, offset: Int, length: Int): String =
java.lang.String(bytes, offset, length, Charsets.UTF_8) as 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.
*/
@kotlin.internal.InlineOnly
public inline fun String(bytes: ByteArray): String =
java.lang.String(bytes, Charsets.UTF_8) as String
/**
* Converts the characters in the specified array to a string.
*/
@kotlin.internal.InlineOnly
public actual inline fun String(chars: CharArray): String =
java.lang.String(chars) as String
/**
* Converts the characters from a portion of the specified array to a string.
*
* @throws IndexOutOfBoundsException if either [offset] or [length] are less than zero
* or `offset + length` is out of [chars] array bounds.
*/
@kotlin.internal.InlineOnly
public actual inline fun String(chars: CharArray, offset: Int, length: Int): String =
java.lang.String(chars, offset, length) as String
/**
* Converts the code points from a portion of the specified Unicode code point array to a string.
*/
@kotlin.internal.InlineOnly
public inline fun String(codePoints: IntArray, offset: Int, length: Int): String =
java.lang.String(codePoints, offset, length) as String
/**
* Converts the contents of the specified StringBuffer to a string.
*/
@kotlin.internal.InlineOnly
public inline fun String(stringBuffer: java.lang.StringBuffer): String =
java.lang.String(stringBuffer) as String
/**
* Converts the contents of the specified StringBuilder to a string.
*/
@kotlin.internal.InlineOnly
public inline fun String(stringBuilder: java.lang.StringBuilder): String =
java.lang.String(stringBuilder) as String
/**
* Returns the character (Unicode code point) at the specified index.
*/
@kotlin.internal.InlineOnly
public inline fun String.codePointAt(index: Int): Int = (this as java.lang.String).codePointAt(index)
/**
* Returns the character (Unicode code point) before the specified index.
*/
@kotlin.internal.InlineOnly
public inline fun String.codePointBefore(index: Int): Int = (this as java.lang.String).codePointBefore(index)
/**
* Returns the number of Unicode code points in the specified text range of this String.
*/
@kotlin.internal.InlineOnly
public inline fun String.codePointCount(beginIndex: Int, endIndex: Int): Int =
(this as java.lang.String).codePointCount(beginIndex, endIndex)
/**
* Compares two strings lexicographically, optionally ignoring case differences.
*/
@Suppress("ACTUAL_FUNCTION_WITH_DEFAULT_ARGUMENTS")
public actual fun String.compareTo(other: String, ignoreCase: Boolean = false): Int {
if (ignoreCase)
return (this as java.lang.String).compareToIgnoreCase(other)
else
return (this as java.lang.String).compareTo(other)
}
/**
* Returns `true` if this string is equal to the contents of the specified [CharSequence], `false` otherwise.
*
* Unlike the overload that accepts an argument of type [StringBuffer],
* this function does not compare this string and the specified [CharSequence] in a synchronized block.
*/
@kotlin.internal.InlineOnly
public inline fun String.contentEquals(charSequence: CharSequence): Boolean = (this as java.lang.String).contentEquals(charSequence)
/**
* Returns `true` if this string is equal to the contents of the specified [StringBuffer], `false` otherwise.
*
* This function compares this string and the specified [StringBuffer] in a synchronized block
* that acquires that [StringBuffer]'s monitor.
*/
@kotlin.internal.InlineOnly
public inline fun String.contentEquals(stringBuilder: StringBuffer): Boolean = (this as java.lang.String).contentEquals(stringBuilder)
/**
* Returns a canonical representation for this string object.
*/
@kotlin.internal.InlineOnly
public inline fun String.intern(): String = (this as java.lang.String).intern()
/**
* Returns `true` if this string is empty or consists solely of whitespace characters.
*
* @sample samples.text.Strings.stringIsBlank
*/
public actual fun CharSequence.isBlank(): Boolean = length == 0 || indices.all { this[it].isWhitespace() }
/**
* Returns the index within this string that is offset from the given [index] by [codePointOffset] code points.
*/
@kotlin.internal.InlineOnly
public inline fun String.offsetByCodePoints(index: Int, codePointOffset: Int): Int =
(this as java.lang.String).offsetByCodePoints(index, codePointOffset)
/**
* Returns `true` if the specified range in this char sequence is equal to the specified range in another char sequence.
* @param thisOffset the start offset in this char sequence of the substring to compare.
* @param other the string against a substring of which the comparison is performed.
* @param otherOffset the start offset in the other char sequence of the substring to compare.
* @param length the length of the substring to compare.
*/
@Suppress("ACTUAL_FUNCTION_WITH_DEFAULT_ARGUMENTS")
public actual fun CharSequence.regionMatches(thisOffset: Int, other: CharSequence, otherOffset: Int, length: Int, ignoreCase: Boolean = false): Boolean {
if (this is String && other is String)
return this.regionMatches(thisOffset, other, otherOffset, length, ignoreCase)
else
return regionMatchesImpl(thisOffset, other, otherOffset, length, ignoreCase)
}
/**
* Returns `true` if the specified range in this string is equal to the specified range in another string.
* @param thisOffset the start offset in this string of the substring to compare.
* @param other the string against a substring of which the comparison is performed.
* @param otherOffset the start offset in the other string of the substring to compare.
* @param length the length of the substring to compare.
*/
public fun String.regionMatches(thisOffset: Int, other: String, otherOffset: Int, length: Int, ignoreCase: Boolean = false): Boolean =
if (!ignoreCase)
(this as java.lang.String).regionMatches(thisOffset, other, otherOffset, length)
else
(this as java.lang.String).regionMatches(ignoreCase, thisOffset, other, otherOffset, length)
/**
* Returns a copy of this string converted to lower case using the rules of the specified locale.
*/
@kotlin.internal.InlineOnly
public inline fun String.toLowerCase(locale: java.util.Locale): String = (this as java.lang.String).toLowerCase(locale)
/**
* Returns a copy of this string converted to upper case using the rules of the specified locale.
*/
@kotlin.internal.InlineOnly
public inline fun String.toUpperCase(locale: java.util.Locale): String = (this as java.lang.String).toUpperCase(locale)
/**
* Encodes the contents of this string using the specified character set and returns the resulting byte array.
* @sample samples.text.Strings.stringToByteArray
*/
@kotlin.internal.InlineOnly
public inline fun String.toByteArray(charset: Charset = Charsets.UTF_8): ByteArray = (this as java.lang.String).getBytes(charset)
/**
* 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.
*/
@kotlin.internal.InlineOnly
public inline fun String.toPattern(flags: Int = 0): java.util.regex.Pattern {
return java.util.regex.Pattern.compile(this, flags)
}
/**
* 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.
*
* The title case of a character is usually the same as its upper case with several exceptions.
* The particular list of characters with the special title case form depends on the underlying platform.
*
* @sample samples.text.Strings.capitalize
*/
public actual fun String.capitalize(): String {
return capitalize(Locale.getDefault())
}
/**
* 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.
*
* The title case of a character is usually the same as its upper case with several exceptions.
* The particular list of characters with the special title case form depends on the underlying platform.
*/
@SinceKotlin("1.4")
@WasExperimental(ExperimentalStdlibApi::class)
@kotlin.internal.LowPriorityInOverloadResolution
public fun String.capitalize(locale: Locale): String {
if (isNotEmpty()) {
val firstChar = this[0]
if (firstChar.isLowerCase()) {
return buildString {
val titleChar = firstChar.toTitleCase()
if (titleChar != firstChar.toUpperCase()) {
append(titleChar)
} else {
append([email protected](0, 1).toUpperCase(locale))
}
append([email protected](1))
}
}
}
return this
}
/**
* 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.
*
* @sample samples.text.Strings.decapitalize
*/
public actual fun String.decapitalize(): String {
return if (isNotEmpty() && !this[0].isLowerCase()) substring(0, 1).toLowerCase() + substring(1) else this
}
/**
* 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.
*/
@SinceKotlin("1.4")
@WasExperimental(ExperimentalStdlibApi::class)
@kotlin.internal.LowPriorityInOverloadResolution
public fun String.decapitalize(locale: Locale): String {
return if (isNotEmpty() && !this[0].isLowerCase()) substring(0, 1).toLowerCase(locale) + substring(1) else this
}
/**
* Returns a string containing this char sequence repeated [n] times.
* @throws [IllegalArgumentException] when n < 0.
* @sample samples.text.Strings.repeat
*/
public actual fun CharSequence.repeat(n: Int): String {
require(n >= 0) { "Count 'n' must be non-negative, but was $n." }
return when (n) {
0 -> ""
1 -> this.toString()
else -> {
when (length) {
0 -> ""
1 -> this[0].let { char -> String(CharArray(n) { char }) }
else -> {
val sb = StringBuilder(n * length)
for (i in 1..n) {
sb.append(this)
}
sb.toString()
}
}
}
}
}
/**
* A Comparator that orders strings ignoring character case.
*
* Note that this Comparator does not take locale into account,
* and will result in an unsatisfactory ordering for certain locales.
*/
public actual val String.Companion.CASE_INSENSITIVE_ORDER: Comparator
get() = java.lang.String.CASE_INSENSITIVE_ORDER