Packages

sealed abstract class Maybe[A] extends AnyRef

An optional value

A Maybe[A] will either be a wrapped A instance (Just[A]), or a lack of underlying A instance (Empty[A]).

Maybe[A] is isomorphic to Option[A], however there are some differences between the two. Maybe is invariant in A while Option is covariant. Maybe[A] does not expose an unsafe get operation to access the underlying A value (that may not exist) like Option[A] does. Maybe[A] does not come with an implicit conversion to Iterable[A] (a trait with over a dozen super types).

Source
Maybe.scala
Linear Supertypes
AnyRef, Any
Known Subclasses
Empty, Just
Ordering
  1. Alphabetic
  2. By Inheritance
Inherited
  1. Maybe
  2. AnyRef
  3. Any
  1. Hide All
  2. Show All
Visibility
  1. Public
  2. All

Value Members

  1. final def !=(arg0: Any): Boolean
    Definition Classes
    AnyRef → Any
  2. final def ##(): Int
    Definition Classes
    AnyRef → Any
  3. final def <\/[B](b: ⇒ B): \/[A, B]

    alias for toLeft

  4. final def ==(arg0: Any): Boolean
    Definition Classes
    AnyRef → Any
  5. final def \/>[B](b: ⇒ B): \/[B, A]

    alias for toRight

  6. final def asInstanceOf[T0]: T0
    Definition Classes
    Any
  7. final def cata[B](f: (A) ⇒ B, b: ⇒ B): B

    Catamorphism.

    Catamorphism. Run the given function on the underlying value if present, otherwise return the provided fallback value

  8. def clone(): AnyRef
    Attributes
    protected[java.lang]
    Definition Classes
    AnyRef
    Annotations
    @native() @throws(classOf[java.lang.CloneNotSupportedException])
  9. final def cobind[B](f: (Maybe[A]) ⇒ B): Maybe[B]
  10. final def cojoin: Maybe[Maybe[A]]
  11. final def eq(arg0: AnyRef): Boolean
    Definition Classes
    AnyRef
  12. def equals(arg0: Any): Boolean
    Definition Classes
    AnyRef → Any
  13. final def exists(f: (A) ⇒ Boolean): Boolean

    Return true if this is a Maybe.Just and the underlying value satisfies the provided predicate

  14. final def filter(f: (A) ⇒ Boolean): Maybe[A]
  15. final def filterNot(f: (A) ⇒ Boolean): Maybe[A]
  16. def finalize(): Unit
    Attributes
    protected[java.lang]
    Definition Classes
    AnyRef
    Annotations
    @throws(classOf[java.lang.Throwable])
  17. final def first: FirstMaybe[A]

    Tag with Tags.First

  18. final def flatMap[B](f: (A) ⇒ Maybe[B]): Maybe[B]
  19. final def forall(f: (A) ⇒ Boolean): Boolean

    Return true if this is a Maybe.Empty or if this is a Maybe.Just and the underlying value satisfies the provided predicate

  20. final def getClass(): Class[_]
    Definition Classes
    AnyRef → Any
    Annotations
    @native()
  21. final def getOrElse(a: ⇒ A): A

    Return the underlying value if present, otherwise the provided fallback value

  22. final def getOrElseF[F[_]](fa: ⇒ F[A])(implicit arg0: Applicative[F]): F[A]
  23. def hashCode(): Int
    Definition Classes
    AnyRef → Any
    Annotations
    @native()
  24. final def isEmpty: Boolean

    True if no underlying value is present

  25. final def isInstanceOf[T0]: Boolean
    Definition Classes
    Any
  26. final def isJust: Boolean

    True if an underlying value is present

  27. final def last: LastMaybe[A]

    Tag with Tags.Last

  28. final def map[B](f: (A) ⇒ B): Maybe[B]
  29. final def max: MaxMaybe[A]

    Tag with Tags.Max

  30. final def min: MinMaybe[A]

    Tag with Tags.Min

  31. final def ne(arg0: AnyRef): Boolean
    Definition Classes
    AnyRef
  32. final def notify(): Unit
    Definition Classes
    AnyRef
    Annotations
    @native()
  33. final def notifyAll(): Unit
    Definition Classes
    AnyRef
    Annotations
    @native()
  34. final def orElse(oa: ⇒ Maybe[A]): Maybe[A]

    Return this instance if it is a Maybe.Just, otherwise the provided fallback

  35. final def orEmpty[F[_]](implicit F: Applicative[F], G: PlusEmpty[F]): F[A]

    Return the underlying value wrapped in type F if present, otherwise the empty value for type F

  36. final def orError[F[_], E](e: E)(implicit F: MonadError[F, E]): F[A]
  37. final def orZero(implicit F: Monoid[A]): A

    Return the underlying value if present, otherwise the monoid zero

  38. final def synchronized[T0](arg0: ⇒ T0): T0
    Definition Classes
    AnyRef
  39. final def toFailure[B](b: ⇒ B): Validation[A, B]

    Turn the underlying value into a failure validation if present, otherwise return a success validation with the provided fallback value

  40. final def toLeft[B](b: ⇒ B): \/[A, B]

    Turn the underlying value into a left disjunction if present, otherwise return a right disjunction with the provided fallback value

  41. final def toOption: Option[A]

    Convert to a standard library Option

  42. final def toRight[B](b: ⇒ B): \/[B, A]

    Turn the underlying value into a right disjunction if present, otherwise return a left disjunction with the provided fallback value

  43. def toString(): String
    Definition Classes
    AnyRef → Any
  44. final def toSuccess[B](b: ⇒ B): Validation[B, A]

    Turn the underlying value into a success validation if present, otherwise return a failure validation with the provided fallback value

  45. final def unary_~(implicit z: Monoid[A]): A

    alias for orZero

  46. final def wait(): Unit
    Definition Classes
    AnyRef
    Annotations
    @throws(classOf[java.lang.InterruptedException])
  47. final def wait(arg0: Long, arg1: Int): Unit
    Definition Classes
    AnyRef
    Annotations
    @throws(classOf[java.lang.InterruptedException])
  48. final def wait(arg0: Long): Unit
    Definition Classes
    AnyRef
    Annotations
    @native() @throws(classOf[java.lang.InterruptedException])
  49. final def zip[B](fb: Maybe[B]): Maybe[(A, B)]
  50. final def zipWith[B, C](fb: Maybe[B])(f: (A, B) ⇒ C): Maybe[C]
  51. final def |(a: ⇒ A): A

    alias for getOrElse

Inherited from AnyRef

Inherited from Any

Ungrouped