Either

scala.util.Either

See theEither companion class

object Either

Attributes

Companion: class
Source: Either.scala
Graph
Supertypes: class Object

trait Matchable

class Any
Self type: Either.type

Members list

Type members

Classlikes

Projects an Either into a Left.

Type parameters

A: the type of the Left value
B: the type of the Right value

Value parameters

e: the Either value to project

Attributes

See also: scala.util.Either#left
Source: Either.scala
Supertypes: trait Serializable

trait Product

trait Equals

class Object

trait Matchable

class Any
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Allows use of a merge method to extract values from Either instances regardless of whether they are Left or Right.

val l = Left(List(1)): Either[List[Int], Vector[Int]]
val r = Right(Vector(1)): Either[List[Int], Vector[Int]]
l.merge: Seq[Int] // List(1)
r.merge: Seq[Int] // Vector(1)

Type parameters

A: the common type of both sides of the Either

Value parameters

x: the Either instance whose left and right types are the same

Attributes

Source: Either.scala
Supertypes: class AnyVal

trait Matchable

class Any

Deprecated classlikes

Projects an Either into a Right.

Because Either is already right-biased, this class is not normally needed. (It is retained in the library for now for easy cross-compilation between Scala 2.11 and 2.12.)

Attributes

Deprecated: [Since version 2.13.0] Either is now right-biased, calls to `right` should be removed
Source: Either.scala
Supertypes: trait Serializable

trait Product

trait Equals

class Object

trait Matchable

class Any
Show all

Value members

Concrete methods

If the condition is satisfied, return the given B in Right, otherwise, return the given A in Left.

val userInput: String = readLine()
Either.cond(
  userInput.forall(_.isDigit) && userInput.size == 10,
  PhoneNumber(userInput),
  s"The input ($userInput) does not look like a phone number"

Type parameters

A: the Left type
B: the Right type

Value parameters

left: the Left value to use if test is false, evaluated lazily
right: the Right value to use if test is true, evaluated lazily
test: the condition to evaluate

Attributes

Returns: Right(right) if test is true, Left(left) otherwise
Source: Either.scala

Implicits

Allows use of a merge method to extract values from Either instances regardless of whether they are Left or Right.

val l = Left(List(1)): Either[List[Int], Vector[Int]]
val r = Right(Vector(1)): Either[List[Int], Vector[Int]]
l.merge: Seq[Int] // List(1)
r.merge: Seq[Int] // Vector(1)

Type parameters

A: the common type of both sides of the Either

Value parameters

x: the Either instance whose left and right types are the same

Attributes

Source: Either.scala

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