Packages

trait Applicative[F[_]] extends Apply[F] with ApplicativeParent[F]

Applicative Functor, described in Applicative Programming with Effects

Whereas a scalaz.Functor allows application of a pure function to a value in a context, an Applicative also allows application of a function in a context to a value in a context (ap).

It follows that a pure function can be applied to arguments in a context. (See apply2, apply3, ... )

Applicative instances come in a few flavours:

  • All scalaz.Monads are also Applicative
  • Any scalaz.Monoid can be treated as an Applicative (see scalaz.Monoid#applicative)
  • Zipping together corresponding elements of Naperian data structures (those of of a fixed, possibly infinite shape)
Self Type
Applicative[F]
Source
Applicative.scala
See also

scalaz.Applicative.ApplicativeLaw

Linear Supertypes
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Inherited
  1. Applicative
  2. ApplicativeParent
  3. Apply
  4. ApplyParent
  5. Functor
  6. InvariantFunctor
  7. AnyRef
  8. Any
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Visibility
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Type Members

  1. trait ApplicativeLaw extends ApplyLaw
  2. trait ApplyLaw extends FunctorLaw
    Definition Classes
    Apply
  3. trait FunctorLaw extends InvariantFunctorLaw
    Definition Classes
    Functor
  4. trait InvariantFunctorLaw extends AnyRef
    Definition Classes
    InvariantFunctor

Abstract Value Members

  1. abstract def ap[A, B](fa: ⇒ F[A])(f: ⇒ F[(A) ⇒ B]): F[B]

    Sequence f, then fa, combining their results by function application.

    Sequence f, then fa, combining their results by function application.

    NB: with respect to apply2 and all other combinators, as well as scalaz.Bind, the f action appears to the *left*. So f should be the "first" F-action to perform. This is in accordance with all other implementations of this typeclass in common use, which are "function first".

    Definition Classes
    Apply
  2. abstract def point[A](a: ⇒ A): F[A]

Concrete Value Members

  1. final def !=(arg0: Any): Boolean
    Definition Classes
    AnyRef → Any
  2. final def ##(): Int
    Definition Classes
    AnyRef → Any
  3. final def ==(arg0: Any): Boolean
    Definition Classes
    AnyRef → Any
  4. def ap2[A, B, C](fa: ⇒ F[A], fb: ⇒ F[B])(f: F[(A, B) ⇒ C]): F[C]
    Definition Classes
    Apply
  5. def ap3[A, B, C, D](fa: ⇒ F[A], fb: ⇒ F[B], fc: ⇒ F[C])(f: F[(A, B, C) ⇒ D]): F[D]
    Definition Classes
    Apply
  6. def ap4[A, B, C, D, E](fa: ⇒ F[A], fb: ⇒ F[B], fc: ⇒ F[C], fd: ⇒ F[D])(f: F[(A, B, C, D) ⇒ E]): F[E]
    Definition Classes
    Apply
  7. def ap5[A, B, C, D, E, R](fa: ⇒ F[A], fb: ⇒ F[B], fc: ⇒ F[C], fd: ⇒ F[D], fe: ⇒ F[E])(f: F[(A, B, C, D, E) ⇒ R]): F[R]
    Definition Classes
    Apply
  8. def ap6[A, B, C, D, E, FF, R](fa: ⇒ F[A], fb: ⇒ F[B], fc: ⇒ F[C], fd: ⇒ F[D], fe: ⇒ F[E], ff: ⇒ F[FF])(f: F[(A, B, C, D, E, FF) ⇒ R]): F[R]
    Definition Classes
    Apply
  9. def ap7[A, B, C, D, E, FF, G, R](fa: ⇒ F[A], fb: ⇒ F[B], fc: ⇒ F[C], fd: ⇒ F[D], fe: ⇒ F[E], ff: ⇒ F[FF], fg: ⇒ F[G])(f: F[(A, B, C, D, E, FF, G) ⇒ R]): F[R]
    Definition Classes
    Apply
  10. def ap8[A, B, C, D, E, FF, G, H, R](fa: ⇒ F[A], fb: ⇒ F[B], fc: ⇒ F[C], fd: ⇒ F[D], fe: ⇒ F[E], ff: ⇒ F[FF], fg: ⇒ F[G], fh: ⇒ F[H])(f: F[(A, B, C, D, E, FF, G, H) ⇒ R]): F[R]
    Definition Classes
    Apply
  11. def apF[A, B](f: ⇒ F[(A) ⇒ B]): (F[A]) ⇒ F[B]

    Flipped variant of ap.

    Flipped variant of ap.

    Definition Classes
    Apply
  12. def applicativeLaw: ApplicativeLaw
  13. val applicativeSyntax: ApplicativeSyntax[F]
  14. def apply[A, B](fa: F[A])(f: (A) ⇒ B): F[B]

    Alias for map.

    Alias for map.

    Definition Classes
    Functor
  15. def apply10[A, B, C, D, E, FF, G, H, I, J, R](fa: ⇒ F[A], fb: ⇒ F[B], fc: ⇒ F[C], fd: ⇒ F[D], fe: ⇒ F[E], ff: ⇒ F[FF], fg: ⇒ F[G], fh: ⇒ F[H], fi: ⇒ F[I], fj: ⇒ F[J])(f: (A, B, C, D, E, FF, G, H, I, J) ⇒ R): F[R]
    Definition Classes
    Apply
  16. def apply11[A, B, C, D, E, FF, G, H, I, J, K, R](fa: ⇒ F[A], fb: ⇒ F[B], fc: ⇒ F[C], fd: ⇒ F[D], fe: ⇒ F[E], ff: ⇒ F[FF], fg: ⇒ F[G], fh: ⇒ F[H], fi: ⇒ F[I], fj: ⇒ F[J], fk: ⇒ F[K])(f: (A, B, C, D, E, FF, G, H, I, J, K) ⇒ R): F[R]
    Definition Classes
    Apply
  17. def apply12[A, B, C, D, E, FF, G, H, I, J, K, L, R](fa: ⇒ F[A], fb: ⇒ F[B], fc: ⇒ F[C], fd: ⇒ F[D], fe: ⇒ F[E], ff: ⇒ F[FF], fg: ⇒ F[G], fh: ⇒ F[H], fi: ⇒ F[I], fj: ⇒ F[J], fk: ⇒ F[K], fl: ⇒ F[L])(f: (A, B, C, D, E, FF, G, H, I, J, K, L) ⇒ R): F[R]
    Definition Classes
    Apply
  18. def apply2[A, B, C](fa: ⇒ F[A], fb: ⇒ F[B])(f: (A, B) ⇒ C): F[C]
    Definition Classes
    ApplicativeApply
  19. def apply3[A, B, C, D](fa: ⇒ F[A], fb: ⇒ F[B], fc: ⇒ F[C])(f: (A, B, C) ⇒ D): F[D]
    Definition Classes
    Apply
  20. def apply4[A, B, C, D, E](fa: ⇒ F[A], fb: ⇒ F[B], fc: ⇒ F[C], fd: ⇒ F[D])(f: (A, B, C, D) ⇒ E): F[E]
    Definition Classes
    Apply
  21. def apply5[A, B, C, D, E, R](fa: ⇒ F[A], fb: ⇒ F[B], fc: ⇒ F[C], fd: ⇒ F[D], fe: ⇒ F[E])(f: (A, B, C, D, E) ⇒ R): F[R]
    Definition Classes
    Apply
  22. def apply6[A, B, C, D, E, FF, R](fa: ⇒ F[A], fb: ⇒ F[B], fc: ⇒ F[C], fd: ⇒ F[D], fe: ⇒ F[E], ff: ⇒ F[FF])(f: (A, B, C, D, E, FF) ⇒ R): F[R]
    Definition Classes
    Apply
  23. def apply7[A, B, C, D, E, FF, G, R](fa: ⇒ F[A], fb: ⇒ F[B], fc: ⇒ F[C], fd: ⇒ F[D], fe: ⇒ F[E], ff: ⇒ F[FF], fg: ⇒ F[G])(f: (A, B, C, D, E, FF, G) ⇒ R): F[R]
    Definition Classes
    Apply
  24. def apply8[A, B, C, D, E, FF, G, H, R](fa: ⇒ F[A], fb: ⇒ F[B], fc: ⇒ F[C], fd: ⇒ F[D], fe: ⇒ F[E], ff: ⇒ F[FF], fg: ⇒ F[G], fh: ⇒ F[H])(f: (A, B, C, D, E, FF, G, H) ⇒ R): F[R]
    Definition Classes
    Apply
  25. def apply9[A, B, C, D, E, FF, G, H, I, R](fa: ⇒ F[A], fb: ⇒ F[B], fc: ⇒ F[C], fd: ⇒ F[D], fe: ⇒ F[E], ff: ⇒ F[FF], fg: ⇒ F[G], fh: ⇒ F[H], fi: ⇒ F[I])(f: (A, B, C, D, E, FF, G, H, I) ⇒ R): F[R]
    Definition Classes
    Apply
  26. def applyApplicative: Applicative[[α]\/[F[α], α]]

    Add a unit to any Apply to form an Applicative.

    Add a unit to any Apply to form an Applicative.

    Definition Classes
    Apply
  27. def applyLaw: ApplyLaw
    Definition Classes
    Apply
  28. val applySyntax: ApplySyntax[F]
    Definition Classes
    Apply
  29. final def asInstanceOf[T0]: T0
    Definition Classes
    Any
  30. def bicompose[G[_, _]](implicit arg0: Bifunctor[G]): Bifunctor[[α, β]F[G[α, β]]]

    The composition of Functor F and Bifunctor G, [x, y]F[G[x, y]], is a Bifunctor

    The composition of Functor F and Bifunctor G, [x, y]F[G[x, y]], is a Bifunctor

    Definition Classes
    Functor
  31. def clone(): AnyRef
    Attributes
    protected[java.lang]
    Definition Classes
    AnyRef
    Annotations
    @native() @throws( ... )
  32. def compose[G[_]](implicit G0: Applicative[G]): Applicative[[α]F[G[α]]]

    The composition of Applicatives F and G, [x]F[G[x]], is an Applicative

  33. def compose[G[_]](implicit G0: Apply[G]): Apply[[α]F[G[α]]]

    The composition of Applys F and G, [x]F[G[x]], is a Apply

    The composition of Applys F and G, [x]F[G[x]], is a Apply

    Definition Classes
    Apply
  34. def compose[G[_]](implicit G0: Functor[G]): Functor[[α]F[G[α]]]

    The composition of Functors F and G, [x]F[G[x]], is a Functor

    The composition of Functors F and G, [x]F[G[x]], is a Functor

    Definition Classes
    Functor
  35. def counzip[A, B](a: \/[F[A], F[B]]): F[\/[A, B]]
    Definition Classes
    Functor
  36. def discardLeft[A, B](fa: ⇒ F[A], fb: ⇒ F[B]): F[B]

    Combine fa and fb according to Apply[F] with a function that discards the A(s)

    Combine fa and fb according to Apply[F] with a function that discards the A(s)

    Definition Classes
    ApplyParent
  37. def discardRight[A, B](fa: ⇒ F[A], fb: ⇒ F[B]): F[A]

    Combine fa and fb according to Apply[F] with a function that discards the B(s)

    Combine fa and fb according to Apply[F] with a function that discards the B(s)

    Definition Classes
    ApplyParent
  38. final def eq(arg0: AnyRef): Boolean
    Definition Classes
    AnyRef
  39. def equals(arg0: Any): Boolean
    Definition Classes
    AnyRef → Any
  40. def filterM[A](l: List[A])(f: (A) ⇒ F[Boolean]): F[List[A]]

    Filter l according to an applicative predicate.

  41. def finalize(): Unit
    Attributes
    protected[java.lang]
    Definition Classes
    AnyRef
    Annotations
    @throws( classOf[java.lang.Throwable] )
  42. def flip: Applicative[F]

    An Applicative for F in which effects happen in the opposite order.

    An Applicative for F in which effects happen in the opposite order.

    Definition Classes
    ApplicativeApplyParent
  43. def forever[A, B](fa: F[A]): F[B]

    Repeats an applicative action infinitely

    Repeats an applicative action infinitely

    Definition Classes
    ApplyParent
  44. def fpair[A](fa: F[A]): F[(A, A)]

    Twin all As in fa.

    Twin all As in fa.

    Definition Classes
    Functor
  45. def fproduct[A, B](fa: F[A])(f: (A) ⇒ B): F[(A, B)]

    Pair all As in fa with the result of function application.

    Pair all As in fa with the result of function application.

    Definition Classes
    Functor
  46. def functorLaw: FunctorLaw
    Definition Classes
    Functor
  47. val functorSyntax: FunctorSyntax[F]
    Definition Classes
    Functor
  48. final def getClass(): Class[_]
    Definition Classes
    AnyRef → Any
    Annotations
    @native()
  49. def hashCode(): Int
    Definition Classes
    AnyRef → Any
    Annotations
    @native()
  50. def icompose[G[_]](implicit G0: Contravariant[G]): Contravariant[[α]F[G[α]]]

    The composition of Functor F and Contravariant G, [x]F[G[x]], is contravariant.

    The composition of Functor F and Contravariant G, [x]F[G[x]], is contravariant.

    Definition Classes
    Functor
  51. def invariantFunctorLaw: InvariantFunctorLaw
    Definition Classes
    InvariantFunctor
  52. val invariantFunctorSyntax: InvariantFunctorSyntax[F]
    Definition Classes
    InvariantFunctor
  53. final def isInstanceOf[T0]: Boolean
    Definition Classes
    Any
  54. def lift[A, B](f: (A) ⇒ B): (F[A]) ⇒ F[B]

    Lift f into F.

    Lift f into F.

    Definition Classes
    Functor
  55. def lift10[A, B, C, D, E, FF, G, H, I, J, R](f: (A, B, C, D, E, FF, G, H, I, J) ⇒ R): (F[A], F[B], F[C], F[D], F[E], F[FF], F[G], F[H], F[I], F[J]) ⇒ F[R]
    Definition Classes
    Apply
  56. def lift11[A, B, C, D, E, FF, G, H, I, J, K, R](f: (A, B, C, D, E, FF, G, H, I, J, K) ⇒ R): (F[A], F[B], F[C], F[D], F[E], F[FF], F[G], F[H], F[I], F[J], F[K]) ⇒ F[R]
    Definition Classes
    Apply
  57. def lift12[A, B, C, D, E, FF, G, H, I, J, K, L, R](f: (A, B, C, D, E, FF, G, H, I, J, K, L) ⇒ R): (F[A], F[B], F[C], F[D], F[E], F[FF], F[G], F[H], F[I], F[J], F[K], F[L]) ⇒ F[R]
    Definition Classes
    Apply
  58. def lift2[A, B, C](f: (A, B) ⇒ C): (F[A], F[B]) ⇒ F[C]
    Definition Classes
    Apply
  59. def lift3[A, B, C, D](f: (A, B, C) ⇒ D): (F[A], F[B], F[C]) ⇒ F[D]
    Definition Classes
    Apply
  60. def lift4[A, B, C, D, E](f: (A, B, C, D) ⇒ E): (F[A], F[B], F[C], F[D]) ⇒ F[E]
    Definition Classes
    Apply
  61. def lift5[A, B, C, D, E, R](f: (A, B, C, D, E) ⇒ R): (F[A], F[B], F[C], F[D], F[E]) ⇒ F[R]
    Definition Classes
    Apply
  62. def lift6[A, B, C, D, E, FF, R](f: (A, B, C, D, E, FF) ⇒ R): (F[A], F[B], F[C], F[D], F[E], F[FF]) ⇒ F[R]
    Definition Classes
    Apply
  63. def lift7[A, B, C, D, E, FF, G, R](f: (A, B, C, D, E, FF, G) ⇒ R): (F[A], F[B], F[C], F[D], F[E], F[FF], F[G]) ⇒ F[R]
    Definition Classes
    Apply
  64. def lift8[A, B, C, D, E, FF, G, H, R](f: (A, B, C, D, E, FF, G, H) ⇒ R): (F[A], F[B], F[C], F[D], F[E], F[FF], F[G], F[H]) ⇒ F[R]
    Definition Classes
    Apply
  65. def lift9[A, B, C, D, E, FF, G, H, I, R](f: (A, B, C, D, E, FF, G, H, I) ⇒ R): (F[A], F[B], F[C], F[D], F[E], F[FF], F[G], F[H], F[I]) ⇒ F[R]
    Definition Classes
    Apply
  66. def map[A, B](fa: F[A])(f: (A) ⇒ B): F[B]

    Lift f into F and apply to F[A].

    Lift f into F and apply to F[A].

    Definition Classes
    ApplicativeFunctor
  67. def mapply[A, B](a: A)(f: F[(A) ⇒ B]): F[B]

    Lift apply(a), and apply the result to f.

    Lift apply(a), and apply the result to f.

    Definition Classes
    Functor
  68. final def ne(arg0: AnyRef): Boolean
    Definition Classes
    AnyRef
  69. final def notify(): Unit
    Definition Classes
    AnyRef
    Annotations
    @native()
  70. final def notifyAll(): Unit
    Definition Classes
    AnyRef
    Annotations
    @native()
  71. def par: Par[F]

    A lawful implementation of this that is isomorphic up to the methods defined on Applicative allowing for optimised parallel implementations that would otherwise violate laws of more specific typeclasses (e.g.

    A lawful implementation of this that is isomorphic up to the methods defined on Applicative allowing for optimised parallel implementations that would otherwise violate laws of more specific typeclasses (e.g. Monad).

    Definition Classes
    ApplicativeParent
  72. def product[G[_]](implicit G0: Applicative[G]): Applicative[[α](F[α], G[α])]

    The product of Applicatives F and G, [x](F[x], G[x]]), is an Applicative

  73. def product[G[_]](implicit G0: Apply[G]): Apply[[α](F[α], G[α])]

    The product of Applys F and G, [x](F[x], G[x]]), is a Apply

    The product of Applys F and G, [x](F[x], G[x]]), is a Apply

    Definition Classes
    Apply
  74. def product[G[_]](implicit G0: Functor[G]): Functor[[α](F[α], G[α])]

    The product of Functors F and G, [x](F[x], G[x]]), is a Functor

    The product of Functors F and G, [x](F[x], G[x]]), is a Functor

    Definition Classes
    Functor
  75. final def pure[A](a: ⇒ A): F[A]
  76. def replicateM[A](n: Int, fa: F[A]): F[List[A]]

    Performs the action n times, returning the list of results.

  77. def replicateM_[A](n: Int, fa: F[A]): F[Unit]

    Performs the action n times, returning nothing.

  78. def sequence[A, G[_]](as: G[F[A]])(implicit arg0: Traverse[G]): F[G[A]]
  79. def sequence1[A, G[_]](as: G[F[A]])(implicit arg0: Traverse1[G]): F[G[A]]
    Definition Classes
    Apply
  80. def strengthL[A, B](a: A, f: F[B]): F[(A, B)]

    Inject a to the left of Bs in f.

    Inject a to the left of Bs in f.

    Definition Classes
    Functor
  81. def strengthR[A, B](f: F[A], b: B): F[(A, B)]

    Inject b to the right of As in f.

    Inject b to the right of As in f.

    Definition Classes
    Functor
  82. final def synchronized[T0](arg0: ⇒ T0): T0
    Definition Classes
    AnyRef
  83. def toString(): String
    Definition Classes
    AnyRef → Any
  84. def traverse[A, G[_], B](value: G[A])(f: (A) ⇒ F[B])(implicit G: Traverse[G]): F[G[B]]
  85. def traverse1[A, G[_], B](value: G[A])(f: (A) ⇒ F[B])(implicit G: Traverse1[G]): F[G[B]]
    Definition Classes
    Apply
  86. def tuple2[A, B](fa: ⇒ F[A], fb: ⇒ F[B]): F[(A, B)]
    Definition Classes
    Apply
  87. def tuple3[A, B, C](fa: ⇒ F[A], fb: ⇒ F[B], fc: ⇒ F[C]): F[(A, B, C)]
    Definition Classes
    Apply
  88. def tuple4[A, B, C, D](fa: ⇒ F[A], fb: ⇒ F[B], fc: ⇒ F[C], fd: ⇒ F[D]): F[(A, B, C, D)]
    Definition Classes
    Apply
  89. def tuple5[A, B, C, D, E](fa: ⇒ F[A], fb: ⇒ F[B], fc: ⇒ F[C], fd: ⇒ F[D], fe: ⇒ F[E]): F[(A, B, C, D, E)]
    Definition Classes
    Apply
  90. def unlessM[A](cond: Boolean)(f: ⇒ F[A]): F[Unit]

    Returns the given argument if cond is false, otherwise, unit lifted into F.

  91. def void[A](fa: F[A]): F[Unit]

    Empty fa of meaningful pure values, preserving its structure.

    Empty fa of meaningful pure values, preserving its structure.

    Definition Classes
    Functor
  92. final def wait(): Unit
    Definition Classes
    AnyRef
    Annotations
    @throws( ... )
  93. final def wait(arg0: Long, arg1: Int): Unit
    Definition Classes
    AnyRef
    Annotations
    @throws( ... )
  94. final def wait(arg0: Long): Unit
    Definition Classes
    AnyRef
    Annotations
    @native() @throws( ... )
  95. def whenM[A](cond: Boolean)(f: ⇒ F[A]): F[Unit]

    Returns the given argument if cond is true, otherwise, unit lifted into F.

  96. def widen[A, B](fa: F[A])(implicit ev: <~<[A, B]): F[B]

    Functors are covariant by nature, so we can treat an F[A] as an F[B] if A is a subtype of B.

    Functors are covariant by nature, so we can treat an F[A] as an F[B] if A is a subtype of B.

    Definition Classes
    Functor
  97. def xmap[A, B](fa: F[A], f: (A) ⇒ B, g: (B) ⇒ A): F[B]

    Converts ma to a value of type F[B] using the provided functions f and g.

    Converts ma to a value of type F[B] using the provided functions f and g.

    Definition Classes
    FunctorInvariantFunctor
  98. def xmapb[A, B](ma: F[A])(b: Bijection[A, B]): F[B]

    Converts ma to a value of type F[B] using the provided bijection.

    Converts ma to a value of type F[B] using the provided bijection.

    Definition Classes
    InvariantFunctor
  99. def xmapi[A, B](ma: F[A])(iso: Isomorphism.<=>[A, B]): F[B]

    Converts ma to a value of type F[B] using the provided isomorphism.

    Converts ma to a value of type F[B] using the provided isomorphism.

    Definition Classes
    InvariantFunctor

Inherited from ApplicativeParent[F]

Inherited from Apply[F]

Inherited from ApplyParent[F]

Inherited from Functor[F]

Inherited from InvariantFunctor[F]

Inherited from AnyRef

Inherited from Any

Ungrouped