Scala 3/scala.collection/StringOps

StringOps

final class StringOps(s: String) extends AnyVal

Provides extension methods for strings.

Some of these methods treat strings as a plain collection of Chars without any regard for Unicode handling. Unless the user takes Unicode handling in to account or makes sure the strings don't require such handling, these methods may result in unpaired or invalidly paired surrogate code units.

Companion:
object
Source:
StringOps.scala
class AnyVal
trait Matchable
class Any

Value members

Concrete methods

def *(n: Int): String

Return the current string concatenated n times.

Return the current string concatenated n times.

Source:
StringOps.scala
def ++[B >: Char](suffix: Iterable[B]): IndexedSeq[B]

Alias for concat

Alias for concat

Source:
StringOps.scala
def ++(suffix: IterableOnce[Char]): String

Alias for concat

Alias for concat

Source:
StringOps.scala
def ++(xs: String): String

Alias for concat

Alias for concat

Source:
StringOps.scala
def ++:[B >: Char](prefix: IterableOnce[B]): IndexedSeq[B]

Alias for prependedAll

Alias for prependedAll

Source:
StringOps.scala
def ++:(prefix: String): String

Alias for prependedAll

Alias for prependedAll

Source:
StringOps.scala
def +:[B >: Char](elem: B): IndexedSeq[B]

Alias for prepended

Alias for prepended

Source:
StringOps.scala
def +:(c: Char): String

Alias for prepended

Alias for prepended

Source:
StringOps.scala
def :+[B >: Char](elem: B): IndexedSeq[B]

Alias for appended

Alias for appended

Source:
StringOps.scala
def :+(c: Char): String

Alias for appended

Alias for appended

Source:
StringOps.scala
def :++[B >: Char](suffix: IterableOnce[B]): IndexedSeq[B]

Alias for appendedAll

Alias for appendedAll

Source:
StringOps.scala
def :++(suffix: String): String

Alias for appendedAll

Alias for appendedAll

Source:
StringOps.scala
def <(that: String): Boolean

Returns true if this is less than that

Returns true if this is less than that

Source:
StringOps.scala
def <=(that: String): Boolean

Returns true if this is less than or equal to that.

Returns true if this is less than or equal to that.

Source:
StringOps.scala
def >(that: String): Boolean

Returns true if this is greater than that.

Returns true if this is greater than that.

Source:
StringOps.scala
def >=(that: String): Boolean

Returns true if this is greater than or equal to that.

Returns true if this is greater than or equal to that.

Source:
StringOps.scala
final def addString(b: StringBuilder): StringBuilder

Appends this string to a string builder.

Appends this string to a string builder.

Source:
StringOps.scala
final def addString(b: StringBuilder, sep: String): StringBuilder

Appends this string to a string builder using a separator string.

Appends this string to a string builder using a separator string.

Source:
StringOps.scala
final def addString(b: StringBuilder, start: String, sep: String, end: String): StringBuilder

Appends this string to a string builder using start, end and separator strings.

Appends this string to a string builder using start, end and separator strings.

Source:
StringOps.scala
def appended[B >: Char](elem: B): IndexedSeq[B]

A copy of the string with an element appended

A copy of the string with an element appended

Source:
StringOps.scala
def appended(c: Char): String

A copy of the string with an element appended

A copy of the string with an element appended

Source:
StringOps.scala
def appendedAll[B >: Char](suffix: IterableOnce[B]): IndexedSeq[B]

A copy of the string with all elements from a collection appended

A copy of the string with all elements from a collection appended

Source:
StringOps.scala
def appendedAll(suffix: String): String

A copy of the string with another string appended

A copy of the string with another string appended

Source:
StringOps.scala
def apply(i: Int): Char

Get the char at the specified index.

Get the char at the specified index.

Source:
StringOps.scala
def capitalize: String

Returns this string with first character converted to upper case.

Returns this string with first character converted to upper case. If the first character of the string is capitalized, it is returned unchanged. This method does not convert characters outside the Basic Multilingual Plane (BMP).

Source:
StringOps.scala
def charStepper: IntStepper & EfficientSplit

Steps over characters in this string.

Steps over characters in this string. Values are packed in Int for efficiency and compatibility with Java 8 Streams which have an efficient specialization for Int.

Source:
StringOps.scala
def codePointStepper: IntStepper & EfficientSplit

Steps over code points in this string.

Steps over code points in this string.

Source:
StringOps.scala
def collect(pf: PartialFunction[Char, Char]): String

Builds a new String by applying a partial function to all chars of this String on which the function is defined.

Builds a new String by applying a partial function to all chars of this String on which the function is defined.

Value parameters:
pf

the partial function which filters and maps the String.

Returns:

a new String resulting from applying the given partial function pf to each char on which it is defined and collecting the results.

Source:
StringOps.scala
def collect[B](pf: PartialFunction[Char, B]): IndexedSeq[B]

Builds a new collection by applying a partial function to all chars of this String on which the function is defined.

Builds a new collection by applying a partial function to all chars of this String on which the function is defined.

Type parameters:
B

the element type of the returned collection.

Value parameters:
pf

the partial function which filters and maps the String.

Returns:

a new collection resulting from applying the given partial function pf to each char on which it is defined and collecting the results.

Source:
StringOps.scala
def combinations(n: Int): Iterator[String]

Iterates over combinations.

Iterates over combinations. A _combination_ of length n is a subsequence of the original string, with the chars taken in order. Thus, "xy" and "yy" are both length-2 combinations of "xyy", but "yx" is not. If there is more than one way to generate the same subsequence, only one will be returned.

For example, "xyyy" has three different ways to generate "xy" depending on whether the first, second, or third "y" is selected. However, since all are identical, only one will be chosen. Which of the three will be taken is an implementation detail that is not defined.

Returns:

An Iterator which traverses the possible n-element combinations of this string.

Note:

This method treats a string as a plain sequence of Char code units and makes no attempt to keep surrogate pairs or codepoint sequences together. The user is responsible for making sure such cases are handled correctly. Failing to do so may result in an invalid Unicode string.

Example:

"abbbc".combinations(2) = Iterator(ab, ac, bb, bc)

Source:
StringOps.scala
def compare(that: String): Int
def concat[B >: Char](suffix: IterableOnce[B]): IndexedSeq[B]

Returns a new collection containing the chars from this string followed by the elements from the right hand operand.

Returns a new collection containing the chars from this string followed by the elements from the right hand operand.

Value parameters:
suffix

the collection to append.

Returns:

a new collection which contains all chars of this string followed by all elements of suffix.

Source:
StringOps.scala
def concat(suffix: IterableOnce[Char]): String

Returns a new string containing the chars from this string followed by the chars from the right hand operand.

Returns a new string containing the chars from this string followed by the chars from the right hand operand.

Value parameters:
suffix

the collection to append.

Returns:

a new string which contains all chars of this string followed by all chars of suffix.

Source:
StringOps.scala
def concat(suffix: String): String

Returns a new string containing the chars from this string followed by the chars from the right hand operand.

Returns a new string containing the chars from this string followed by the chars from the right hand operand.

Value parameters:
suffix

the string to append.

Returns:

a new string which contains all chars of this string followed by all chars of suffix.

Source:
StringOps.scala
def contains(elem: Char): Boolean

Tests whether this string contains the given character.

Tests whether this string contains the given character.

Value parameters:
elem

the character to test.

Returns:

true if this string has an element that is equal (as determined by ==) to elem, false otherwise.

Source:
StringOps.scala
def copyToArray(xs: Array[Char]): Int

Copy chars of this string to an array.

Copy chars of this string to an array. Fills the given array xs starting at index 0. Copying will stop once either the entire string has been copied or the end of the array is reached

Value parameters:
xs

the array to fill.

Source:
StringOps.scala
def copyToArray(xs: Array[Char], start: Int): Int

Copy chars of this string to an array.

Copy chars of this string to an array. Fills the given array xs starting at index start. Copying will stop once either the entire string has been copied or the end of the array is reached

Value parameters:
start

the starting index.

xs

the array to fill.

Source:
StringOps.scala
def copyToArray(xs: Array[Char], start: Int, len: Int): Int

Copy chars of this string to an array.

Copy chars of this string to an array. Fills the given array xs starting at index start with at most len chars. Copying will stop once either the entire string has been copied, or the end of the array is reached or len chars have been copied.

Value parameters:
len

the maximal number of elements to copy.

start

the starting index.

xs

the array to fill.

Source:
StringOps.scala
def count(p: Char => Boolean): Int

Counts the number of chars in this string which satisfy a predicate

Counts the number of chars in this string which satisfy a predicate

Source:
StringOps.scala
def diff[B >: Char](that: Seq[B]): String

Computes the multiset difference between this string and another sequence.

Computes the multiset difference between this string and another sequence.

Value parameters:
that

the sequence of chars to remove

Returns:

a new string which contains all chars of this string except some of occurrences of elements that also appear in that. If an element value x appears n times in that, then the first n occurrences of x will not form part of the result, but any following occurrences will.

Note:

This method treats a string as a plain sequence of Char code units and makes no attempt to keep surrogate pairs or codepoint sequences together. The user is responsible for making sure such cases are handled correctly. Failing to do so may result in an invalid Unicode string.

Source:
StringOps.scala
def distinct: String

Selects all distinct chars of this string ignoring the duplicates.

Selects all distinct chars of this string ignoring the duplicates.

Note:

This method treats a string as a plain sequence of Char code units and makes no attempt to keep surrogate pairs or codepoint sequences together. The user is responsible for making sure such cases are handled correctly. Failing to do so may result in an invalid Unicode string.

Source:
StringOps.scala
def distinctBy[B](f: Char => B): String

Selects all distinct chars of this string ignoring the duplicates as determined by == after applying the transforming function f.

Selects all distinct chars of this string ignoring the duplicates as determined by == after applying the transforming function f.

Type parameters:
B

the type of the elements after being transformed by f

Value parameters:
f

The transforming function whose result is used to determine the uniqueness of each element

Returns:

a new string consisting of all the chars of this string without duplicates.

Note:

This method treats a string as a plain sequence of Char code units and makes no attempt to keep surrogate pairs or codepoint sequences together. The user is responsible for making sure such cases are handled correctly. Failing to do so may result in an invalid Unicode string.

Source:
StringOps.scala
def drop(n: Int): String

The rest of the string without its n first chars.

The rest of the string without its n first chars.

Note:

This method treats a string as a plain sequence of Char code units and makes no attempt to keep surrogate pairs or codepoint sequences together. The user is responsible for making sure such cases are handled correctly. Failing to do so may result in an invalid Unicode string.

Source:
StringOps.scala
def dropRight(n: Int): String

The rest of the string without its n last chars.

The rest of the string without its n last chars.

Note:

This method treats a string as a plain sequence of Char code units and makes no attempt to keep surrogate pairs or codepoint sequences together. The user is responsible for making sure such cases are handled correctly. Failing to do so may result in an invalid Unicode string.

Source:
StringOps.scala
def dropWhile(p: Char => Boolean): String

Drops longest prefix of chars that satisfy a predicate.

Drops longest prefix of chars that satisfy a predicate.

Value parameters:
p

The predicate used to test elements.

Returns:

the longest suffix of this string whose first element does not satisfy the predicate p.

Source:
StringOps.scala
def exists(p: Char => Boolean): Boolean

Tests whether a predicate holds for at least one char of this string.

Tests whether a predicate holds for at least one char of this string.

Source:
StringOps.scala
def filter(pred: Char => Boolean): String

Selects all chars of this string which satisfy a predicate.

Selects all chars of this string which satisfy a predicate.

Source:
StringOps.scala
def filterNot(pred: Char => Boolean): String

Selects all chars of this string which do not satisfy a predicate.

Selects all chars of this string which do not satisfy a predicate.

Source:
StringOps.scala
def find(p: Char => Boolean): Option[Char]

Finds the first char of the string satisfying a predicate, if any.

Finds the first char of the string satisfying a predicate, if any.

Value parameters:
p

the predicate used to test elements.

Returns:

an option value containing the first element in the string that satisfies p, or None if none exists.

Source:
StringOps.scala
def flatMap[B](f: Char => IterableOnce[B]): IndexedSeq[B]

Builds a new collection by applying a function to all chars of this string and using the elements of the resulting collections.

Builds a new collection by applying a function to all chars of this string and using the elements of the resulting collections.

Value parameters:
f

the function to apply to each char.

Returns:

a new collection resulting from applying the given collection-valued function f to each char of this string and concatenating the results.

Source:
StringOps.scala
def flatMap(f: Char => String): String

Builds a new string by applying a function to all chars of this string and using the elements of the resulting strings.

Builds a new string by applying a function to all chars of this string and using the elements of the resulting strings.

Value parameters:
f

the function to apply to each char.

Returns:

a new string resulting from applying the given string-valued function f to each char of this string and concatenating the results.

Source:
StringOps.scala
def fold[A1 >: Char](z: A1)(op: (A1, A1) => A1): A1

Folds the chars of this string using the specified associative binary operator.

Folds the chars of this string using the specified associative binary operator.

Type parameters:
A1

a type parameter for the binary operator, a supertype of Char.

Value parameters:
op

a binary operator that must be associative.

z

a neutral element for the fold operation; may be added to the result an arbitrary number of times, and must not change the result (e.g., Nil for list concatenation, 0 for addition, or 1 for multiplication).

Returns:

the result of applying the fold operator op between all the chars and z, or z if this string is empty.

Source:
StringOps.scala
def foldLeft[B](z: B)(op: (B, Char) => B): B

Applies a binary operator to a start value and all chars of this string, going left to right.

Applies a binary operator to a start value and all chars of this string, going left to right.

Type parameters:
B

the result type of the binary operator.

Value parameters:
op

the binary operator.

z

the start value.

Returns:

the result of inserting op between consecutive chars of this string, going left to right with the start value z on the left:

op(...op(z, x_1), x_2, ..., x_n)

where x1, ..., xn are the chars of this string. Returns z if this string is empty.

Source:
StringOps.scala
def foldRight[B](z: B)(op: (Char, B) => B): B

Applies a binary operator to all chars of this string and a start value, going right to left.

Applies a binary operator to all chars of this string and a start value, going right to left.

Type parameters:
B

the result type of the binary operator.

Value parameters:
op

the binary operator.

z

the start value.

Returns:

the result of inserting op between consecutive chars of this string, going right to left with the start value z on the right:

op(x_1, op(x_2, ... op(x_n, z)...))

where x1, ..., xn are the chars of this string. Returns z if this string is empty.

Source:
StringOps.scala
def forall(@deprecatedName("f", "2.13.3") p: Char => Boolean): Boolean

Tests whether a predicate holds for all chars of this string.

Tests whether a predicate holds for all chars of this string.

Value parameters:
p

the predicate used to test elements.

Returns:

true if this string is empty or the given predicate p holds for all chars of this string, otherwise false.

Source:
StringOps.scala
def foreach[U](f: Char => U): Unit

Apply f to each element for its side effects.

Apply f to each element for its side effects. Note: [U] parameter needed to help scalac's type inference.

Source:
StringOps.scala
def format(args: Any*): String

Uses the underlying string as a pattern (in a fashion similar to printf in C), and uses the supplied arguments to fill in the holes.

Uses the underlying string as a pattern (in a fashion similar to printf in C), and uses the supplied arguments to fill in the holes.

The interpretation of the formatting patterns is described in java.util.Formatter, with the addition that classes deriving from ScalaNumber (such as scala.BigInt and scala.BigDecimal) are unwrapped to pass a type which Formatter understands.

Value parameters:
args

the arguments used to instantiating the pattern.

Source:
StringOps.scala
def formatLocal(l: Locale, args: Any*): String

Like format(args*) but takes an initial Locale parameter which influences formatting as in java.lang.String's format.

Like format(args*) but takes an initial Locale parameter which influences formatting as in java.lang.String's format.

The interpretation of the formatting patterns is described in java.util.Formatter, with the addition that classes deriving from ScalaNumber (such as scala.BigInt and scala.BigDecimal) are unwrapped to pass a type which Formatter understands.

Value parameters:
args

the arguments used to instantiating the pattern.

l

an instance of java.util.Locale

Source:
StringOps.scala
def groupBy[K](f: Char => K): Map[K, String]

Partitions this string into a map of strings according to some discriminator function.

Partitions this string into a map of strings according to some discriminator function.

Type parameters:
K

the type of keys returned by the discriminator function.

Value parameters:
f

the discriminator function.

Returns:

A map from keys to strings such that the following invariant holds:

(xs groupBy f)(k) = xs filter (x => f(x) == k)

That is, every key k is bound to a string of those elements x for which f(x) equals k.

Note:

This method treats a string as a plain sequence of Char code units and makes no attempt to keep surrogate pairs or codepoint sequences together. The user is responsible for making sure such cases are handled correctly. Failing to do so may result in an invalid Unicode string.

Source:
StringOps.scala
def grouped(size: Int): Iterator[String]

Partitions elements in fixed size strings.

Partitions elements in fixed size strings.

Value parameters:
size

the number of elements per group

Returns:

An iterator producing strings of size size, except the last will be less than size size if the elements don't divide evenly.

See also:
Note:

This method treats a string as a plain sequence of Char code units and makes no attempt to keep surrogate pairs or codepoint sequences together. The user is responsible for making sure such cases are handled correctly. Failing to do so may result in an invalid Unicode string.

Source:
StringOps.scala
def head: Char

Selects the first char of this string.

Selects the first char of this string.

Returns:

the first char of this string.

Throws:
NoSuchElementException

if the string is empty.

Source:
StringOps.scala
def headOption: Option[Char]

Optionally selects the first char.

Optionally selects the first char.

Returns:

the first char of this string if it is nonempty, None if it is empty.

Source:
StringOps.scala
def indexWhere(p: Char => Boolean, from: Int): Int

Finds index of the first char satisfying some predicate after or at some start index.

Finds index of the first char satisfying some predicate after or at some start index.

Value parameters:
from

the start index

p

the predicate used to test elements.

Returns:

the index >= from of the first element of this string that satisfies the predicate p, or -1, if none exists.

Source:
StringOps.scala
def indices: Range

Produces the range of all indices of this string.

Produces the range of all indices of this string.

Returns:

a Range value from 0 to one less than the length of this string.

Source:
StringOps.scala
def init: String

The initial part of the string without its last char.

The initial part of the string without its last char.

Note:

This method treats a string as a plain sequence of Char code units and makes no attempt to keep surrogate pairs or codepoint sequences together. The user is responsible for making sure such cases are handled correctly. Failing to do so may result in an invalid Unicode string.

Source:
StringOps.scala
def inits: Iterator[String]

Iterates over the inits of this string.

Iterates over the inits of this string. The first value will be this string and the final one will be an empty string, with the intervening values the results of successive applications of init.

Returns:

an iterator over all the inits of this string

Note:

This method treats a string as a plain sequence of Char code units and makes no attempt to keep surrogate pairs or codepoint sequences together. The user is responsible for making sure such cases are handled correctly. Failing to do so may result in an invalid Unicode string.

Source:
StringOps.scala
def intersect[B >: Char](that: Seq[B]): String

Computes the multiset intersection between this string and another sequence.

Computes the multiset intersection between this string and another sequence.

Value parameters:
that

the sequence of chars to intersect with.

Returns:

a new string which contains all chars of this string which also appear in that. If an element value x appears n times in that, then the first n occurrences of x will be retained in the result, but any following occurrences will be omitted.

Note:

This method treats a string as a plain sequence of Char code units and makes no attempt to keep surrogate pairs or codepoint sequences together. The user is responsible for making sure such cases are handled correctly. Failing to do so may result in an invalid Unicode string.

Source:
StringOps.scala
def iterator: Iterator[Char]

Iterator can be used only once

Iterator can be used only once

Source:
StringOps.scala
def last: Char

Selects the last char of this string.

Selects the last char of this string.

Returns:

the last char of this string.

Throws:
NoSuchElementException

if the string is empty.

Source:
StringOps.scala
def lastIndexWhere(p: Char => Boolean, end: Int): Int

Finds index of the last char satisfying some predicate before or at some end index.

Finds index of the last char satisfying some predicate before or at some end index.

Value parameters:
end

the end index

p

the predicate used to test elements.

Returns:

the index <= end of the last element of this string that satisfies the predicate p, or -1, if none exists.

Source:
StringOps.scala
def lastOption: Option[Char]

Optionally selects the last char.

Optionally selects the last char.

Returns:

the last char of this string if it is nonempty, None if it is empty.

Source:
StringOps.scala
def lazyZip[B](that: Iterable[B]): LazyZip2[Char, B, String]

Analogous to zip except that the elements in each collection are not consumed until a strict operation is invoked on the returned LazyZip2 decorator.

Analogous to zip except that the elements in each collection are not consumed until a strict operation is invoked on the returned LazyZip2 decorator.

Calls to lazyZip can be chained to support higher arities (up to 4) without incurring the expense of constructing and deconstructing intermediary tuples.

val xs = List(1, 2, 3)
val res = (xs lazyZip xs lazyZip xs lazyZip xs).map((a, b, c, d) => a + b + c + d)
// res == List(4, 8, 12)
Type parameters:
B

the type of the second element in each eventual pair

Value parameters:
that

the iterable providing the second element of each eventual pair

Returns:

a decorator LazyZip2 that allows strict operations to be performed on the lazily evaluated pairs or chained calls to lazyZip. Implicit conversion to Iterable[(A, B)] is also supported.

Source:
StringOps.scala
def linesIterator: Iterator[String]

Lines in this string, where a line is terminated by "\n", "\r", "\r\n", or the end of the string.

Lines in this string, where a line is terminated by "\n", "\r", "\r\n", or the end of the string. A line may be empty. Line terminators are removed.

Source:
StringOps.scala
def linesWithSeparators: Iterator[String]

Return an iterator of all lines embedded in this string, including trailing line separator characters.

Return an iterator of all lines embedded in this string, including trailing line separator characters.

The empty string yields an empty iterator.

Source:
StringOps.scala
def map[B](f: Char => B): IndexedSeq[B]

Builds a new collection by applying a function to all chars of this string.

Builds a new collection by applying a function to all chars of this string.

Value parameters:
f

the function to apply to each char.

Returns:

a new collection resulting from applying the given function f to each char of this string and collecting the results.

Source:
StringOps.scala
def map(f: Char => Char): String

Builds a new string by applying a function to all chars of this string.

Builds a new string by applying a function to all chars of this string.

Value parameters:
f

the function to apply to each char.

Returns:

a new string resulting from applying the given function f to each char of this string and collecting the results.

Source:
StringOps.scala
final def mkString(start: String, sep: String, end: String): String

Displays all elements of this string in a string using start, end, and separator strings.

Displays all elements of this string in a string using start, end, and separator strings.

Value parameters:
end

the ending string.

sep

the separator string.

start

the starting string.

Returns:

The resulting string begins with the string start and ends with the string end. Inside, the string chars of this string are separated by the string sep.

Note:

This method treats a string as a plain sequence of Char code units and makes no attempt to keep surrogate pairs or codepoint sequences together. The user is responsible for making sure such cases are handled correctly. Failing to do so may result in an invalid Unicode string.

Source:
StringOps.scala
final def mkString(sep: String): String

Displays all elements of this string in a string using a separator string.

Displays all elements of this string in a string using a separator string.

Value parameters:
sep

the separator string.

Returns:

In the resulting string the chars of this string are separated by the string sep.

Note:

This method treats a string as a plain sequence of Char code units and makes no attempt to keep surrogate pairs or codepoint sequences together. The user is responsible for making sure such cases are handled correctly. Failing to do so may result in an invalid Unicode string.

Source:
StringOps.scala
final def mkString: String

Returns this string

Returns this string

Source:
StringOps.scala
def nonEmpty: Boolean

Tests whether the string is not empty.

Tests whether the string is not empty.

Source:
StringOps.scala
def padTo[B >: Char](len: Int, elem: B): IndexedSeq[B]

Returns a collection with an element appended until a given target length is reached.

Returns a collection with an element appended until a given target length is reached.

Value parameters:
elem

the padding value

len

the target length

Returns:

a collection consisting of this string followed by the minimal number of occurrences of elem so that the resulting collection has a length of at least len.

Source:
StringOps.scala
def padTo(len: Int, elem: Char): String

Returns a string with a char appended until a given target length is reached.

Returns a string with a char appended until a given target length is reached.

Value parameters:
elem

the padding value

len

the target length

Returns:

a string consisting of this string followed by the minimal number of occurrences of elem so that the resulting string has a length of at least len.

Source:
StringOps.scala
def partition(p: Char => Boolean): (String, String)

A pair of, first, all chars that satisfy predicate p and, second, all chars that do not.

A pair of, first, all chars that satisfy predicate p and, second, all chars that do not.

Source:
StringOps.scala
def partitionMap(f: Char => Either[Char, Char]): (String, String)

Applies a function f to each character of the string and returns a pair of strings: the first one made of those characters returned by f that were wrapped in scala.util.Left, and the second one made of those wrapped in scala.util.Right.

Applies a function f to each character of the string and returns a pair of strings: the first one made of those characters returned by f that were wrapped in scala.util.Left, and the second one made of those wrapped in scala.util.Right.

Example:

val xs = "1one2two3three" partitionMap { c =>
  if (c > 'a') Left(c) else Right(c)
}
// xs == ("onetwothree", "123")
Value parameters:
f

the 'split function' mapping the elements of this string to an scala.util.Either

Returns:

a pair of strings: the first one made of those characters returned by f that were wrapped in scala.util.Left, and the second one made of those wrapped in scala.util.Right.

Source:
StringOps.scala
def patch[B >: Char](from: Int, other: IterableOnce[B], replaced: Int): IndexedSeq[B]

Produces a new collection where a slice of characters in this string is replaced by another collection.

Produces a new collection where a slice of characters in this string is replaced by another collection.

Patching at negative indices is the same as patching starting at 0. Patching at indices at or larger than the length of the original string appends the patch to the end. If more values are replaced than actually exist, the excess is ignored.

Value parameters:
from

the index of the first replaced char

other

the replacement collection

replaced

the number of chars to drop in the original string

Returns:

a new collection consisting of all chars of this string except that replaced chars starting from from are replaced by other.

Source:
StringOps.scala
def patch(from: Int, other: IterableOnce[Char], replaced: Int): String

Produces a new collection where a slice of characters in this string is replaced by another collection.

Produces a new collection where a slice of characters in this string is replaced by another collection.

Patching at negative indices is the same as patching starting at 0. Patching at indices at or larger than the length of the original string appends the patch to the end. If more values are replaced than actually exist, the excess is ignored.

Value parameters:
from

the index of the first replaced char

other

the replacement string

replaced

the number of chars to drop in the original string

Returns:

a new string consisting of all chars of this string except that replaced chars starting from from are replaced by other.

Note:

This method treats a string as a plain sequence of Char code units and makes no attempt to keep surrogate pairs or codepoint sequences together. The user is responsible for making sure such cases are handled correctly. Failing to do so may result in an invalid Unicode string.

Source:
StringOps.scala
def patch(from: Int, other: String, replaced: Int): String

Produces a new string where a slice of characters in this string is replaced by another string.

Produces a new string where a slice of characters in this string is replaced by another string.

Patching at negative indices is the same as patching starting at 0. Patching at indices at or larger than the length of the original string appends the patch to the end. If more values are replaced than actually exist, the excess is ignored.

Value parameters:
from

the index of the first replaced char

other

the replacement string

replaced

the number of chars to drop in the original string

Returns:

a new string consisting of all chars of this string except that replaced chars starting from from are replaced by other.

Note:

This method treats a string as a plain sequence of Char code units and makes no attempt to keep surrogate pairs or codepoint sequences together. The user is responsible for making sure such cases are handled correctly. Failing to do so may result in an invalid Unicode string.

Source:
StringOps.scala
def permutations: Iterator[String]

Iterates over distinct permutations.

Iterates over distinct permutations.

Returns:

An Iterator which traverses the distinct permutations of this string.

Note:

This method treats a string as a plain sequence of Char code units and makes no attempt to keep surrogate pairs or codepoint sequences together. The user is responsible for making sure such cases are handled correctly. Failing to do so may result in an invalid Unicode string.

Example:

"abb".permutations = Iterator(abb, bab, bba)

Source:
StringOps.scala
def prepended[B >: Char](elem: B): IndexedSeq[B]

A copy of the string with an element prepended

A copy of the string with an element prepended

Source:
StringOps.scala
def prepended(c: Char): String

A copy of the string with an char prepended

A copy of the string with an char prepended

Source:
StringOps.scala
def prependedAll[B >: Char](prefix: IterableOnce[B]): IndexedSeq[B]

A copy of the string with all elements from a collection prepended

A copy of the string with all elements from a collection prepended

Source:
StringOps.scala
def prependedAll(prefix: String): String

A copy of the string with another string prepended

A copy of the string with another string prepended

Source:
StringOps.scala
def r: Regex

You can follow a string with .r, turning it into a Regex.

You can follow a string with .r, turning it into a Regex. E.g.

"""A\w*""".r is the regular expression for identifiers starting with A.

Source:
StringOps.scala
def r(groupNames: String*): Regex

You can follow a string with .r(g1, ... , gn), turning it into a Regex, with group names g1 through gn.

You can follow a string with .r(g1, ... , gn), turning it into a Regex, with group names g1 through gn.

"""(\d\d)-(\d\d)-(\d\d\d\d)""".r("month", "day", "year") matches dates and provides its subcomponents through groups named "month", "day" and "year".

Value parameters:
groupNames

The names of the groups in the pattern, in the order they appear.

Source:
StringOps.scala
def reverse: String

Returns new sequence with elements in reversed order.

Returns new sequence with elements in reversed order.

Note:

This method treats a string as a plain sequence of Char code units and makes no attempt to keep surrogate pairs or codepoint sequences together. The user is responsible for making sure such cases are handled correctly. Failing to do so may result in an invalid Unicode string.

Source:
StringOps.scala
def reverseIterator: Iterator[Char]

An iterator yielding chars in reversed order.

An iterator yielding chars in reversed order.

Note: xs.reverseIterator is the same as xs.reverse.iterator but implemented more efficiently.

Returns:

an iterator yielding the chars of this string in reversed order

Source:
StringOps.scala
def sizeCompare(otherSize: Int): Int
def slice(from: Int, until: Int): String

Selects an interval of elements.

Selects an interval of elements. The returned string is made up of all elements x which satisfy the invariant:

from <= indexOf(x) < until
Value parameters:
from

the lowest index to include from this string.

until

the lowest index to EXCLUDE from this string.

Returns:

a string containing the elements greater than or equal to index from extending up to (but not including) index until of this string.

Note:

This method treats a string as a plain sequence of Char code units and makes no attempt to keep surrogate pairs or codepoint sequences together. The user is responsible for making sure such cases are handled correctly. Failing to do so may result in an invalid Unicode string.

Source:
StringOps.scala
def sliding(size: Int, step: Int): Iterator[String]

Groups chars in fixed size blocks by passing a "sliding window" over them (as opposed to partitioning them, as is done in grouped.)

Groups chars in fixed size blocks by passing a "sliding window" over them (as opposed to partitioning them, as is done in grouped.)

Value parameters:
size

the number of chars per group

step

the distance between the first chars of successive groups

Returns:

An iterator producing strings of size size, except the last element (which may be the only element) will be truncated if there are fewer than size chars remaining to be grouped.

See also:
Note:

This method treats a string as a plain sequence of Char code units and makes no attempt to keep surrogate pairs or codepoint sequences together. The user is responsible for making sure such cases are handled correctly. Failing to do so may result in an invalid Unicode string.

Source:
StringOps.scala
def sortBy[B](f: Char => B)(implicit ord: Ordering[B]): String

Sorts this string according to the Ordering which results from transforming an implicitly given Ordering with a transformation function.

Sorts this string according to the Ordering which results from transforming an implicitly given Ordering with a transformation function.

The sort is stable. That is, elements that are equal (as determined by ord.compare) appear in the same order in the sorted sequence as in the original.

Type parameters:
B

the target type of the transformation f, and the type where the ordering ord is defined.

Value parameters:
f

the transformation function mapping elements to some other domain B.

ord

the ordering assumed on domain B.

Returns:

a string consisting of the chars of this string sorted according to the ordering where x < y if ord.lt(f(x), f(y)).

See also:
Note:

This method treats a string as a plain sequence of Char code units and makes no attempt to keep surrogate pairs or codepoint sequences together. The user is responsible for making sure such cases are handled correctly. Failing to do so may result in an invalid Unicode string.

Source:
StringOps.scala
def sortWith(lt: (Char, Char) => Boolean): String

Sorts this string according to a comparison function.

Sorts this string according to a comparison function.

The sort is stable. That is, elements that are equal (as determined by lt) appear in the same order in the sorted sequence as in the original.

Value parameters:
lt

the comparison function which tests whether its first argument precedes its second argument in the desired ordering.

Returns:

a string consisting of the elements of this string sorted according to the comparison function lt.

Note:

This method treats a string as a plain sequence of Char code units and makes no attempt to keep surrogate pairs or codepoint sequences together. The user is responsible for making sure such cases are handled correctly. Failing to do so may result in an invalid Unicode string.

Source:
StringOps.scala
def sorted[B >: Char](implicit ord: Ordering[B]): String

Sorts the characters of this string according to an Ordering.

Sorts the characters of this string according to an Ordering.

The sort is stable. That is, elements that are equal (as determined by ord.compare) appear in the same order in the sorted sequence as in the original.

Value parameters:
ord

the ordering to be used to compare elements.

Returns:

a string consisting of the chars of this string sorted according to the ordering ord.

See also:
Note:

This method treats a string as a plain sequence of Char code units and makes no attempt to keep surrogate pairs or codepoint sequences together. The user is responsible for making sure such cases are handled correctly. Failing to do so may result in an invalid Unicode string.

Source:
StringOps.scala
def span(p: Char => Boolean): (String, String)

Splits this string into a prefix/suffix pair according to a predicate.

Splits this string into a prefix/suffix pair according to a predicate.

Note: c span p is equivalent to (but more efficient than) (c takeWhile p, c dropWhile p), provided the evaluation of the predicate p does not cause any side-effects.

Value parameters:
p

the test predicate

Returns:

a pair consisting of the longest prefix of this string whose chars all satisfy p, and the rest of this string.

Source:
StringOps.scala
def split(separator: Char): Array[String]

Split this string around the separator character

Split this string around the separator character

If this string is the empty string, returns an array of strings that contains a single empty string.

If this string is not the empty string, returns an array containing the substrings terminated by the start of the string, the end of the string or the separator character, excluding empty trailing substrings

If the separator character is a surrogate character, only split on matching surrogate characters if they are not part of a surrogate pair

The behaviour follows, and is implemented in terms of String.split(re: String)

Value parameters:
separator

the character used as a delimiter

Example:

"a.b".split('.') //returns Array("a", "b")
//splitting the empty string always returns the array with a single
//empty string
"".split('.') //returns Array("")
//only trailing empty substrings are removed
"a.".split('.') //returns Array("a")
".a.".split('.') //returns Array("", "a")
"..a..".split('.') //returns Array("", "", "a")
//all parts are empty and trailing
".".split('.') //returns Array()
"..".split('.') //returns Array()
//surrogate pairs
val high = 0xD852.toChar
val low = 0xDF62.toChar
val highstring = high.toString
val lowstring = low.toString
//well-formed surrogate pairs are not split
val highlow = highstring + lowstring
highlow.split(high) //returns Array(highlow)
//bare surrogate characters are split
val bare = "_" + highstring + "_"
bare.split(high) //returns Array("_", "_")
Source:
StringOps.scala
@throws(scala.Predef.classOf[java.util.regex.PatternSyntaxException])
def split(separators: Array[Char]): Array[String]
def splitAt(n: Int): (String, String)

Splits this string into two at a given position.

Splits this string into two at a given position. Note: c splitAt n is equivalent to (c take n, c drop n).

Value parameters:
n

the position at which to split.

Returns:

a pair of strings consisting of the first n chars of this string, and the other chars.

Note:

This method treats a string as a plain sequence of Char code units and makes no attempt to keep surrogate pairs or codepoint sequences together. The user is responsible for making sure such cases are handled correctly. Failing to do so may result in an invalid Unicode string.

Source:
StringOps.scala
def stepper: IntStepper & EfficientSplit

Stepper can be used with Java 8 Streams.

Stepper can be used with Java 8 Streams. This method is equivalent to a call to charStepper. See also codePointStepper.

Source:
StringOps.scala
def stripLineEnd: String

Strip the trailing line separator from this string if there is one.

Strip the trailing line separator from this string if there is one. The line separator is taken as "\n", "\r", or "\r\n".

Source:
StringOps.scala
def stripMargin(marginChar: Char): String

For every line in this string:

For every line in this string:

Strip a leading prefix consisting of blanks or control characters followed by marginChar from the line.

Source:
StringOps.scala
def stripMargin: String

For every line in this string:

For every line in this string:

Strip a leading prefix consisting of blanks or control characters followed by | from the line.

Source:
StringOps.scala
def stripPrefix(prefix: String): String

Returns this string with the given prefix stripped.

Returns this string with the given prefix stripped. If this string does not start with prefix, it is returned unchanged.

Source:
StringOps.scala
def stripSuffix(suffix: String): String

Returns this string with the given suffix stripped.

Returns this string with the given suffix stripped. If this string does not end with suffix, it is returned unchanged.

Source:
StringOps.scala
def tail: String

The rest of the string without its first char.

The rest of the string without its first char.

Note:

This method treats a string as a plain sequence of Char code units and makes no attempt to keep surrogate pairs or codepoint sequences together. The user is responsible for making sure such cases are handled correctly. Failing to do so may result in an invalid Unicode string.

Source:
StringOps.scala
def tails: Iterator[String]

Iterates over the tails of this string.

Iterates over the tails of this string. The first value will be this string and the final one will be an empty string, with the intervening values the results of successive applications of tail.

Returns:

an iterator over all the tails of this string

Note:

This method treats a string as a plain sequence of Char code units and makes no attempt to keep surrogate pairs or codepoint sequences together. The user is responsible for making sure such cases are handled correctly. Failing to do so may result in an invalid Unicode string.

Source:
StringOps.scala
def take(n: Int): String

A string containing the first n chars of this string.

A string containing the first n chars of this string.

Note:

This method treats a string as a plain sequence of Char code units and makes no attempt to keep surrogate pairs or codepoint sequences together. The user is responsible for making sure such cases are handled correctly. Failing to do so may result in an invalid Unicode string.

Source:
StringOps.scala
def takeRight(n: Int): String

A string containing the last n chars of this string.

A string containing the last n chars of this string.

Note:

This method treats a string as a plain sequence of Char code units and makes no attempt to keep surrogate pairs or codepoint sequences together. The user is responsible for making sure such cases are handled correctly. Failing to do so may result in an invalid Unicode string.

Source:
StringOps.scala
def takeWhile(p: Char => Boolean): String

Takes longest prefix of chars that satisfy a predicate.

Takes longest prefix of chars that satisfy a predicate.

Source:
StringOps.scala
def toArray[B >: Char](implicit tag: ClassTag[B]): Array[B]
def toBoolean: Boolean
Throws:
java.lang.IllegalArgumentException

If the string does not contain a parsable Boolean.

Source:
StringOps.scala
def toBooleanOption: Option[Boolean]

Try to parse as a Boolean

Try to parse as a Boolean

Returns:

Some(true) if the string is "true" case insensitive, Some(false) if the string is "false" case insensitive, and None if the string is anything else

Throws:
java.lang.NullPointerException

if the string is null

Source:
StringOps.scala
def toByte: Byte

Parse as a Byte (string must contain only decimal digits and optional leading - or +).

Parse as a Byte (string must contain only decimal digits and optional leading - or +).

Throws:
java.lang.NumberFormatException

If the string does not contain a parsable Byte.

Source:
StringOps.scala
def toByteOption: Option[Byte]

Try to parse as a Byte

Try to parse as a Byte

Returns:

Some(value) if the string contains a valid byte value, otherwise None

Throws:
java.lang.NullPointerException

if the string is null

Source:
StringOps.scala
def toDouble: Double

Parse as a Double (surrounding whitespace is removed with a trim).

Parse as a Double (surrounding whitespace is removed with a trim).

Throws:
java.lang.NullPointerException

If the string is null.

java.lang.NumberFormatException

If the string does not contain a parsable Double.

Source:
StringOps.scala
def toDoubleOption: Option[Double]

Try to parse as a Double

Try to parse as a Double

Returns:

Some(value) if the string is a parsable Double, None otherwise

Throws:
java.lang.NullPointerException

If the string is null

Source:
StringOps.scala
def toFloat: Float

Parse as a Float (surrounding whitespace is removed with a trim).

Parse as a Float (surrounding whitespace is removed with a trim).

Throws:
java.lang.NullPointerException

If the string is null.

java.lang.NumberFormatException

If the string does not contain a parsable Float.

Source:
StringOps.scala
def toFloatOption: Option[Float]

Try to parse as a Float

Try to parse as a Float

Returns:

Some(value) if the string is a parsable Float, None otherwise

Throws:
java.lang.NullPointerException

If the string is null

Source:
StringOps.scala
def toInt: Int

Parse as an Int (string must contain only decimal digits and optional leading - or +).

Parse as an Int (string must contain only decimal digits and optional leading - or +).

Throws:
java.lang.NumberFormatException

If the string does not contain a parsable Int.

Source:
StringOps.scala
def toIntOption: Option[Int]

Try to parse as an Int

Try to parse as an Int

Returns:

Some(value) if the string contains a valid Int value, otherwise None

Throws:
java.lang.NullPointerException

if the string is null

Source:
StringOps.scala
def toLong: Long

Parse as a Long (string must contain only decimal digits and optional leading - or +).

Parse as a Long (string must contain only decimal digits and optional leading - or +).

Throws:
java.lang.NumberFormatException

If the string does not contain a parsable Long.

Source:
StringOps.scala
def toLongOption: Option[Long]

Try to parse as a Long

Try to parse as a Long

Returns:

Some(value) if the string contains a valid long value, otherwise None

Throws:
java.lang.NullPointerException

if the string is null

Source:
StringOps.scala
def toShort: Short

Parse as a Short (string must contain only decimal digits and optional leading - or +).

Parse as a Short (string must contain only decimal digits and optional leading - or +).

Throws:
java.lang.NumberFormatException

If the string does not contain a parsable Short.

Source:
StringOps.scala
def toShortOption: Option[Short]

Try to parse as a Short

Try to parse as a Short

Returns:

Some(value) if the string contains a valid short value, otherwise None

Throws:
java.lang.NullPointerException

if the string is null

Source:
StringOps.scala
def updated(index: Int, elem: Char): String

A copy of this string with one single replaced element.

A copy of this string with one single replaced element.

Value parameters:
elem

the replacing element

index

the position of the replacement

Returns:

a new string which is a copy of this string with the element at position index replaced by elem.

Throws:
IndexOutOfBoundsException

if index does not satisfy 0 <= index < length.

Note:

This method treats a string as a plain sequence of Char code units and makes no attempt to keep surrogate pairs or codepoint sequences together. The user is responsible for making sure such cases are handled correctly. Failing to do so may result in an invalid Unicode string.

Source:
StringOps.scala
def withFilter(p: Char => Boolean): WithFilter

Creates a non-strict filter of this string.

Creates a non-strict filter of this string.

Value parameters:
p

the predicate used to test elements.

Returns:

an object of class stringOps.WithFilter, which supports map, flatMap, foreach, and withFilter operations. All these operations apply to those chars of this string which satisfy the predicate p.

Note:

the difference between c filter p and c withFilter p is that the former creates a new string, whereas the latter only restricts the domain of subsequent map, flatMap, foreach, and withFilter operations.

Source:
StringOps.scala

Deprecated methods

@deprecated("Use `linesIterator`, because JDK 11 adds a `lines` method on String", "2.13.0")
def lines: Iterator[String]

Return all lines in this string in an iterator, excluding trailing line end characters; i.e., apply .stripLineEnd to all lines returned by linesWithSeparators.

Return all lines in this string in an iterator, excluding trailing line end characters; i.e., apply .stripLineEnd to all lines returned by linesWithSeparators.

Deprecated
Source:
StringOps.scala
@deprecated("Use `s.replace` as an exact replacement", "2.13.2")
def replaceAllLiterally(literal: String, replacement: String): String

Replace all literal occurrences of literal with the literal string replacement.

Replace all literal occurrences of literal with the literal string replacement. This method is equivalent to java.lang.String#replace.

Value parameters:
literal

the string which should be replaced everywhere it occurs

replacement

the replacement string

Returns:

the resulting string

Deprecated
Source:
StringOps.scala