LeftProjection

scala.util.Either.LeftProjection
final case class LeftProjection[+A, +B](e: Either[A, B])

Projects an Either into a Left.

Attributes

See also
Source
Either.scala
Graph
Supertypes
trait Serializable
trait Product
trait Equals
class Object
trait Matchable
class Any
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Members list

Value members

Concrete methods

def exists(p: A => Boolean): Boolean

Returns false if Right or returns the result of the application of the given function to the Left value.

Returns false if Right or returns the result of the application of the given function to the Left value.

Left(12).left.exists(_ > 10)  // true
Left(7).left.exists(_ > 10)   // false
Right(12).left.exists(_ > 10) // false

Attributes

Source
Either.scala
def filterToOption[B1](p: A => Boolean): Option[Either[A, B1]]

Returns None if this is a Right or if the given predicate p does not hold for the left value, otherwise, returns a Left.

Returns None if this is a Right or if the given predicate p does not hold for the left value, otherwise, returns a Left.

Left(12).left.filterToOption(_ > 10)  // Some(Left(12))
Left(7).left.filterToOption(_ > 10)   // None
Right(12).left.filterToOption(_ > 10) // None

Attributes

Source
Either.scala
def flatMap[A1, B1 >: B](f: A => Either[A1, B1]): Either[A1, B1]

Binds the given function across Left.

Binds the given function across Left.

Left(12).left.flatMap(x => Left("scala")) // Left("scala")
Right(12).left.flatMap(x => Left("scala")) // Right(12)

Value parameters

f

The function to bind across Left.

Attributes

Source
Either.scala
def forall(p: A => Boolean): Boolean

Returns true if Right or returns the result of the application of the given function to the Left value.

Returns true if Right or returns the result of the application of the given function to the Left value.

Left(12).left.forall(_ > 10)  // true
Left(7).left.forall(_ > 10)   // false
Right(12).left.forall(_ > 10) // true

Attributes

Source
Either.scala
def foreach[U](f: A => U): Unit

Executes the given side-effecting function if this is a Left.

Executes the given side-effecting function if this is a Left.

Left(12).left.foreach(x => println(x))  // prints "12"
Right(12).left.foreach(x => println(x)) // doesn't print

Value parameters

f

The side-effecting function to execute.

Attributes

Source
Either.scala
def getOrElse[A1 >: A](or: => A1): A1

Returns the value from this Left or the given argument if this is a Right.

Returns the value from this Left or the given argument if this is a Right.

Left(12).left.getOrElse(17)  // 12
Right(12).left.getOrElse(17) // 17

Attributes

Source
Either.scala
def map[A1](f: A => A1): Either[A1, B]

Maps the function argument through Left.

Maps the function argument through Left.

Left(12).left.map(_ + 2) // Left(14)
Right[Int, Int](12).left.map(_ + 2) // Right(12)

Attributes

Source
Either.scala
def toOption: Option[A]

Returns a Some containing the Left value if it exists or a None if this is a Right.

Returns a Some containing the Left value if it exists or a None if this is a Right.

Left(12).left.toOption // Some(12)
Right(12).left.toOption // None

Attributes

Source
Either.scala
def toSeq: Seq[A]

Returns a Seq containing the Left value if it exists or an empty Seq if this is a Right.

Returns a Seq containing the Left value if it exists or an empty Seq if this is a Right.

Left(12).left.toSeq // Seq(12)
Right(12).left.toSeq // Seq()

Attributes

Source
Either.scala

Deprecated methods

def filter[B1](p: A => Boolean): Option[Either[A, B1]]

Returns None if this is a Right or if the given predicate p does not hold for the left value, otherwise, returns a Left.

Returns None if this is a Right or if the given predicate p does not hold for the left value, otherwise, returns a Left.

Left(12).left.filter(_ > 10)  // Some(Left(12))
Left(7).left.filter(_ > 10)   // None
Right(12).left.filter(_ > 10) // None

Attributes

Deprecated
true
Source
Either.scala
def get: A

Returns the value from this Left or throws NoSuchElementException if this is a Right.

Returns the value from this Left or throws NoSuchElementException if this is a Right.

Left(12).left.get  // 12
Right(12).left.get // NoSuchElementException

Attributes

Throws
Deprecated
true
Source
Either.scala

Inherited methods

An iterator over the names of all the elements of this product.

An iterator over the names of all the elements of this product.

Attributes

Inherited from:
Product
Source
Product.scala

An iterator over all the elements of this product.

An iterator over all the elements of this product.

Attributes

Returns

in the default implementation, an Iterator[Any]

Inherited from:
Product
Source
Product.scala