scala

Either

class Either[+A, +B] extends AnyRef

The Either type represents a value of one of two possible types (a disjoint union). The data constructors Left and Right represent the two possible values. The Either type is often used as an alternative to scala.Option where Left represents failure (by convention) and Right is akin to Some.

attributes: sealed abstract
known subclasses: Left, Right

Inherits

  1. AnyRef
  2. Any

Value Members

  1. def equals(arg0: Any): Boolean

    This method is used to compare the receiver object (this) with the argument object (arg0) for equivalence

    This method is used to compare the receiver object (this) with the argument object (arg0) for equivalence.

    The default implementations of this method is an equivalence relation:

    • It is reflexive: for any instance x of type Any, x.equals(x) should return true.
    • It is symmetric: for any instances x and y of type Any, x.equals(y) should return true if and only if y.equals(x) returns true.
    • It is transitive: for any instances x, y, and z of type AnyRef if x.equals(y) returns true and y.equals(z) returns true, then x.equals(z) should return true.

    If you override this method, you should verify that your implementation remains an equivalence relation. Additionally, when overriding this method it is often necessary to override hashCode to ensure that objects that are "equal" (o1.equals(o2) returns true) hash to the same Int (o1.hashCode.equals(o2.hashCode)).

    arg0

    the object to compare against this object for equality.

    returns

    true if the receiver object is equivalent to the argument; false otherwise.

    definition classes: AnyRef ⇐ Any

  2. def fold[X](fa: (A) ⇒ X, fb: (B) ⇒ X): X

    Deconstruction of the Either type (in contrast to pattern matching)

    Deconstruction of the Either type (in contrast to pattern matching).

  3. def hashCode(): Int

    Returns a hash code value for the object

    Returns a hash code value for the object.

    The default hashing algorithm is platform dependent.

    Note that it is allowed for two objects to have identical hash codes (o1.hashCode.equals(o2.hashCode)) yet not be equal (o1.equals(o2) returns false). A degenerate implementation could always return 0. However, it is required that if two objects are equal (o1.equals(o2) returns true) that they have identical hash codes (o1.hashCode.equals(o2.hashCode)). Therefore, when overriding this method, be sure to verify that the behavior is consistent with the equals method.

    definition classes: AnyRef ⇐ Any

  4. def isLeft: Boolean

    Returns true if this is a Left, false otherwise

    Returns true if this is a Left, false otherwise.

    attributes: abstract

  5. def isRight: Boolean

    Returns true if this is a Right, false otherwise

    Returns true if this is a Right, false otherwise.

    attributes: abstract

  6. def joinLeft[A1 >: A, B1 >: B, C](ev: <:<[A1, Either[C, B1]]): Either[C, B1]

    Joins an Either through Left

    Joins an Either through Left.

  7. def joinRight[A1 >: A, B1 >: B, C](ev: <:<[B1, Either[A1, C]]): Either[A1, C]

    Joins an Either through Right

    Joins an Either through Right.

  8. def left: LeftProjection[A, B]

    Projects this Either as a Left

    Projects this Either as a Left.

  9. def right: RightProjection[A, B]

    Projects this Either as a Right

    Projects this Either as a Right.

  10. def swap: Product with Either[B, A]

    If this is a Left, then return the left value in Right or vice versa

    If this is a Left, then return the left value in Right or vice versa.

  11. def toString(): String

    Returns a string representation of the object

    Returns a string representation of the object.

    The default representation is platform dependent.

    definition classes: AnyRef ⇐ Any

Instance constructors

  1. new Either()