Class Either.LeftProjection

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

Projects an Either into a Left.

See also	scala.util.Either#left
Supertypes	trait Serializable trait Product trait Equals class Object trait Matchable class Any

Concrete methods

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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.

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

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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.

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

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

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.

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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.

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

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def foreach[U](f: A => U): Unit

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.

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def getOrElse[A1 >: A](or: => A1): A1

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

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

Maps the function argument through Left.

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

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def toOption: Option[A]

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

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def toSeq: Seq[A]

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()

Inherited methods

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def productElementNames: Iterator[String]

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

Inherited from	Product

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def productIterator: Iterator[Any]

An iterator over all the elements of this product.

Returns	in the default implementation, an Iterator[Any]
Inherited from	Product