t

cats

StackSafeMonad

trait StackSafeMonad[F[_]] extends Monad[F]

A mix-in for inheriting tailRecM on monads which define a stack-safe flatMap. This is not an appropriate trait to use unless you are 100% certain your monad is stack-safe by definition! If your monad is not stack-safe, then the tailRecM implementation you will inherit will not be sound, and will result in unexpected stack overflows. This trait is only provided because a large number of monads do define a stack-safe flatMap, and so this particular implementation was being repeated over and over again.

Source
StackSafeMonad.scala
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Inherited
  1. StackSafeMonad
  2. Monad
  3. Applicative
  4. InvariantMonoidal
  5. FlatMap
  6. Apply
  7. ApplyArityFunctions
  8. InvariantSemigroupal
  9. Semigroupal
  10. Functor
  11. Invariant
  12. Serializable
  13. Serializable
  14. AnyRef
  15. Any
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Visibility
  1. Public
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Abstract Value Members

  1. abstract def flatMap[A, B](fa: F[A])(f: (A) ⇒ F[B]): F[B]
    Definition Classes
    FlatMap
  2. abstract def pure[A](x: A): F[A]

    pure lifts any value into the Applicative Functor.

    pure lifts any value into the Applicative Functor.

    Example:

    scala> import cats.implicits._
    
    scala> Applicative[Option].pure(10)
    res0: Option[Int] = Some(10)
    Definition Classes
    Applicative

Concrete Value Members

  1. final def !=(arg0: Any): Boolean
    Definition Classes
    AnyRef → Any
  2. final def ##(): Int
    Definition Classes
    AnyRef → Any
  3. final def *>[A, B](fa: F[A])(fb: F[B]): F[B]

    Alias for productR.

    Alias for productR.

    Definition Classes
    Apply
    Annotations
    @inline()
  4. final def <*[A, B](fa: F[A])(fb: F[B]): F[A]

    Alias for productL.

    Alias for productL.

    Definition Classes
    Apply
    Annotations
    @inline()
  5. final def <*>[A, B](ff: F[(A) ⇒ B])(fa: F[A]): F[B]

    Alias for ap.

    Alias for ap.

    Definition Classes
    Apply
    Annotations
    @inline()
  6. final def ==(arg0: Any): Boolean
    Definition Classes
    AnyRef → Any
  7. def ap[A, B](ff: F[(A) ⇒ B])(fa: F[A]): F[B]

    Given a value and a function in the Apply context, applies the function to the value.

    Given a value and a function in the Apply context, applies the function to the value.

    Example:

    scala> import cats.implicits._
    
    scala> val someF: Option[Int => Long] = Some(_.toLong + 1L)
    scala> val noneF: Option[Int => Long] = None
    scala> val someInt: Option[Int] = Some(3)
    scala> val noneInt: Option[Int] = None
    
    scala> Apply[Option].ap(someF)(someInt)
    res0: Option[Long] = Some(4)
    
    scala> Apply[Option].ap(noneF)(someInt)
    res1: Option[Long] = None
    
    scala> Apply[Option].ap(someF)(noneInt)
    res2: Option[Long] = None
    
    scala> Apply[Option].ap(noneF)(noneInt)
    res3: Option[Long] = None
    Definition Classes
    FlatMapApply
  8. def ap10[A0, A1, A2, A3, A4, A5, A6, A7, A8, A9, Z](f: F[(A0, A1, A2, A3, A4, A5, A6, A7, A8, A9) ⇒ Z])(f0: F[A0], f1: F[A1], f2: F[A2], f3: F[A3], f4: F[A4], f5: F[A5], f6: F[A6], f7: F[A7], f8: F[A8], f9: F[A9]): F[Z]

    Definition Classes
    ApplyArityFunctions
  9. def ap11[A0, A1, A2, A3, A4, A5, A6, A7, A8, A9, A10, Z](f: F[(A0, A1, A2, A3, A4, A5, A6, A7, A8, A9, A10) ⇒ Z])(f0: F[A0], f1: F[A1], f2: F[A2], f3: F[A3], f4: F[A4], f5: F[A5], f6: F[A6], f7: F[A7], f8: F[A8], f9: F[A9], f10: F[A10]): F[Z]

    Definition Classes
    ApplyArityFunctions
  10. def ap12[A0, A1, A2, A3, A4, A5, A6, A7, A8, A9, A10, A11, Z](f: F[(A0, A1, A2, A3, A4, A5, A6, A7, A8, A9, A10, A11) ⇒ Z])(f0: F[A0], f1: F[A1], f2: F[A2], f3: F[A3], f4: F[A4], f5: F[A5], f6: F[A6], f7: F[A7], f8: F[A8], f9: F[A9], f10: F[A10], f11: F[A11]): F[Z]

    Definition Classes
    ApplyArityFunctions
  11. def ap13[A0, A1, A2, A3, A4, A5, A6, A7, A8, A9, A10, A11, A12, Z](f: F[(A0, A1, A2, A3, A4, A5, A6, A7, A8, A9, A10, A11, A12) ⇒ Z])(f0: F[A0], f1: F[A1], f2: F[A2], f3: F[A3], f4: F[A4], f5: F[A5], f6: F[A6], f7: F[A7], f8: F[A8], f9: F[A9], f10: F[A10], f11: F[A11], f12: F[A12]): F[Z]

    Definition Classes
    ApplyArityFunctions
  12. def ap14[A0, A1, A2, A3, A4, A5, A6, A7, A8, A9, A10, A11, A12, A13, Z](f: F[(A0, A1, A2, A3, A4, A5, A6, A7, A8, A9, A10, A11, A12, A13) ⇒ Z])(f0: F[A0], f1: F[A1], f2: F[A2], f3: F[A3], f4: F[A4], f5: F[A5], f6: F[A6], f7: F[A7], f8: F[A8], f9: F[A9], f10: F[A10], f11: F[A11], f12: F[A12], f13: F[A13]): F[Z]

    Definition Classes
    ApplyArityFunctions
  13. def ap15[A0, A1, A2, A3, A4, A5, A6, A7, A8, A9, A10, A11, A12, A13, A14, Z](f: F[(A0, A1, A2, A3, A4, A5, A6, A7, A8, A9, A10, A11, A12, A13, A14) ⇒ Z])(f0: F[A0], f1: F[A1], f2: F[A2], f3: F[A3], f4: F[A4], f5: F[A5], f6: F[A6], f7: F[A7], f8: F[A8], f9: F[A9], f10: F[A10], f11: F[A11], f12: F[A12], f13: F[A13], f14: F[A14]): F[Z]

    Definition Classes
    ApplyArityFunctions
  14. def ap16[A0, A1, A2, A3, A4, A5, A6, A7, A8, A9, A10, A11, A12, A13, A14, A15, Z](f: F[(A0, A1, A2, A3, A4, A5, A6, A7, A8, A9, A10, A11, A12, A13, A14, A15) ⇒ Z])(f0: F[A0], f1: F[A1], f2: F[A2], f3: F[A3], f4: F[A4], f5: F[A5], f6: F[A6], f7: F[A7], f8: F[A8], f9: F[A9], f10: F[A10], f11: F[A11], f12: F[A12], f13: F[A13], f14: F[A14], f15: F[A15]): F[Z]

    Definition Classes
    ApplyArityFunctions
  15. def ap17[A0, A1, A2, A3, A4, A5, A6, A7, A8, A9, A10, A11, A12, A13, A14, A15, A16, Z](f: F[(A0, A1, A2, A3, A4, A5, A6, A7, A8, A9, A10, A11, A12, A13, A14, A15, A16) ⇒ Z])(f0: F[A0], f1: F[A1], f2: F[A2], f3: F[A3], f4: F[A4], f5: F[A5], f6: F[A6], f7: F[A7], f8: F[A8], f9: F[A9], f10: F[A10], f11: F[A11], f12: F[A12], f13: F[A13], f14: F[A14], f15: F[A15], f16: F[A16]): F[Z]

    Definition Classes
    ApplyArityFunctions
  16. def ap18[A0, A1, A2, A3, A4, A5, A6, A7, A8, A9, A10, A11, A12, A13, A14, A15, A16, A17, Z](f: F[(A0, A1, A2, A3, A4, A5, A6, A7, A8, A9, A10, A11, A12, A13, A14, A15, A16, A17) ⇒ Z])(f0: F[A0], f1: F[A1], f2: F[A2], f3: F[A3], f4: F[A4], f5: F[A5], f6: F[A6], f7: F[A7], f8: F[A8], f9: F[A9], f10: F[A10], f11: F[A11], f12: F[A12], f13: F[A13], f14: F[A14], f15: F[A15], f16: F[A16], f17: F[A17]): F[Z]

    Definition Classes
    ApplyArityFunctions
  17. def ap19[A0, A1, A2, A3, A4, A5, A6, A7, A8, A9, A10, A11, A12, A13, A14, A15, A16, A17, A18, Z](f: F[(A0, A1, A2, A3, A4, A5, A6, A7, A8, A9, A10, A11, A12, A13, A14, A15, A16, A17, A18) ⇒ Z])(f0: F[A0], f1: F[A1], f2: F[A2], f3: F[A3], f4: F[A4], f5: F[A5], f6: F[A6], f7: F[A7], f8: F[A8], f9: F[A9], f10: F[A10], f11: F[A11], f12: F[A12], f13: F[A13], f14: F[A14], f15: F[A15], f16: F[A16], f17: F[A17], f18: F[A18]): F[Z]

    Definition Classes
    ApplyArityFunctions
  18. def ap2[A, B, Z](ff: F[(A, B) ⇒ Z])(fa: F[A], fb: F[B]): F[Z]

    ap2 is a binary version of ap, defined in terms of ap.

    ap2 is a binary version of ap, defined in terms of ap.

    Definition Classes
    FlatMapApply
  19. def ap20[A0, A1, A2, A3, A4, A5, A6, A7, A8, A9, A10, A11, A12, A13, A14, A15, A16, A17, A18, A19, Z](f: F[(A0, A1, A2, A3, A4, A5, A6, A7, A8, A9, A10, A11, A12, A13, A14, A15, A16, A17, A18, A19) ⇒ Z])(f0: F[A0], f1: F[A1], f2: F[A2], f3: F[A3], f4: F[A4], f5: F[A5], f6: F[A6], f7: F[A7], f8: F[A8], f9: F[A9], f10: F[A10], f11: F[A11], f12: F[A12], f13: F[A13], f14: F[A14], f15: F[A15], f16: F[A16], f17: F[A17], f18: F[A18], f19: F[A19]): F[Z]

    Definition Classes
    ApplyArityFunctions
  20. def ap21[A0, A1, A2, A3, A4, A5, A6, A7, A8, A9, A10, A11, A12, A13, A14, A15, A16, A17, A18, A19, A20, Z](f: F[(A0, A1, A2, A3, A4, A5, A6, A7, A8, A9, A10, A11, A12, A13, A14, A15, A16, A17, A18, A19, A20) ⇒ Z])(f0: F[A0], f1: F[A1], f2: F[A2], f3: F[A3], f4: F[A4], f5: F[A5], f6: F[A6], f7: F[A7], f8: F[A8], f9: F[A9], f10: F[A10], f11: F[A11], f12: F[A12], f13: F[A13], f14: F[A14], f15: F[A15], f16: F[A16], f17: F[A17], f18: F[A18], f19: F[A19], f20: F[A20]): F[Z]

    Definition Classes
    ApplyArityFunctions
  21. def ap22[A0, A1, A2, A3, A4, A5, A6, A7, A8, A9, A10, A11, A12, A13, A14, A15, A16, A17, A18, A19, A20, A21, Z](f: F[(A0, A1, A2, A3, A4, A5, A6, A7, A8, A9, A10, A11, A12, A13, A14, A15, A16, A17, A18, A19, A20, A21) ⇒ Z])(f0: F[A0], f1: F[A1], f2: F[A2], f3: F[A3], f4: F[A4], f5: F[A5], f6: F[A6], f7: F[A7], f8: F[A8], f9: F[A9], f10: F[A10], f11: F[A11], f12: F[A12], f13: F[A13], f14: F[A14], f15: F[A15], f16: F[A16], f17: F[A17], f18: F[A18], f19: F[A19], f20: F[A20], f21: F[A21]): F[Z]

    Definition Classes
    ApplyArityFunctions
  22. def ap3[A0, A1, A2, Z](f: F[(A0, A1, A2) ⇒ Z])(f0: F[A0], f1: F[A1], f2: F[A2]): F[Z]

    Definition Classes
    ApplyArityFunctions
  23. def ap4[A0, A1, A2, A3, Z](f: F[(A0, A1, A2, A3) ⇒ Z])(f0: F[A0], f1: F[A1], f2: F[A2], f3: F[A3]): F[Z]

    Definition Classes
    ApplyArityFunctions
  24. def ap5[A0, A1, A2, A3, A4, Z](f: F[(A0, A1, A2, A3, A4) ⇒ Z])(f0: F[A0], f1: F[A1], f2: F[A2], f3: F[A3], f4: F[A4]): F[Z]

    Definition Classes
    ApplyArityFunctions
  25. def ap6[A0, A1, A2, A3, A4, A5, Z](f: F[(A0, A1, A2, A3, A4, A5) ⇒ Z])(f0: F[A0], f1: F[A1], f2: F[A2], f3: F[A3], f4: F[A4], f5: F[A5]): F[Z]

    Definition Classes
    ApplyArityFunctions
  26. def ap7[A0, A1, A2, A3, A4, A5, A6, Z](f: F[(A0, A1, A2, A3, A4, A5, A6) ⇒ Z])(f0: F[A0], f1: F[A1], f2: F[A2], f3: F[A3], f4: F[A4], f5: F[A5], f6: F[A6]): F[Z]

    Definition Classes
    ApplyArityFunctions
  27. def ap8[A0, A1, A2, A3, A4, A5, A6, A7, Z](f: F[(A0, A1, A2, A3, A4, A5, A6, A7) ⇒ Z])(f0: F[A0], f1: F[A1], f2: F[A2], f3: F[A3], f4: F[A4], f5: F[A5], f6: F[A6], f7: F[A7]): F[Z]

    Definition Classes
    ApplyArityFunctions
  28. def ap9[A0, A1, A2, A3, A4, A5, A6, A7, A8, Z](f: F[(A0, A1, A2, A3, A4, A5, A6, A7, A8) ⇒ Z])(f0: F[A0], f1: F[A1], f2: F[A2], f3: F[A3], f4: F[A4], f5: F[A5], f6: F[A6], f7: F[A7], f8: F[A8]): F[Z]

    Definition Classes
    ApplyArityFunctions
  29. def as[A, B](fa: F[A], b: B): F[B]

    Replaces the A value in F[A] with the supplied value.

    Replaces the A value in F[A] with the supplied value.

    Example:

    scala> import cats.Functor
    scala> import cats.implicits.catsStdInstancesForList
    
    scala> Functor[List].as(List(1,2,3), "hello")
    res0: List[String] = List(hello, hello, hello)
    Definition Classes
    Functor
  30. final def asInstanceOf[T0]: T0
    Definition Classes
    Any
  31. def clone(): AnyRef
    Attributes
    protected[lang]
    Definition Classes
    AnyRef
    Annotations
    @throws( ... ) @native()
  32. def compose[G[_]](implicit arg0: Applicative[G]): Applicative[[α]F[G[α]]]

    Compose an Applicative[F] and an Applicative[G] into an Applicative[λ[α => F[G[α]]]].

    Compose an Applicative[F] and an Applicative[G] into an Applicative[λ[α => F[G[α]]]].

    Example:

    scala> import cats.implicits._
    
    scala> val alo = Applicative[List].compose[Option]
    
    scala> alo.pure(3)
    res0: List[Option[Int]] = List(Some(3))
    
    scala> alo.product(List(None, Some(true), Some(false)), List(Some(2), None))
    res1: List[Option[(Boolean, Int)]] = List(None, None, Some((true,2)), None, Some((false,2)), None)
    Definition Classes
    Applicative
  33. def compose[G[_]](implicit arg0: Apply[G]): Apply[[α]F[G[α]]]

    Compose an Apply[F] and an Apply[G] into an Apply[λ[α => F[G[α]]]].

    Compose an Apply[F] and an Apply[G] into an Apply[λ[α => F[G[α]]]].

    Example:

    scala> import cats.implicits._
    
    scala> val alo = Apply[List].compose[Option]
    
    scala> alo.product(List(None, Some(true), Some(false)), List(Some(2), None))
    res1: List[Option[(Boolean, Int)]] = List(None, None, Some((true,2)), None, Some((false,2)), None)
    Definition Classes
    Apply
  34. def compose[G[_]](implicit arg0: Functor[G]): Functor[[α]F[G[α]]]
    Definition Classes
    Functor
  35. def compose[G[_]](implicit arg0: Invariant[G]): Invariant[[α]F[G[α]]]
    Definition Classes
    Invariant
  36. def composeApply[G[_]](implicit arg0: Apply[G]): InvariantSemigroupal[[α]F[G[α]]]
    Definition Classes
    InvariantSemigroupal
  37. def composeContravariant[G[_]](implicit arg0: Contravariant[G]): Contravariant[[α]F[G[α]]]
    Definition Classes
    FunctorInvariant
  38. def composeContravariantMonoidal[G[_]](implicit arg0: ContravariantMonoidal[G]): ContravariantMonoidal[[α]F[G[α]]]

    Compose an Applicative[F] and a ContravariantMonoidal[G] into a ContravariantMonoidal[λ[α => F[G[α]]]].

    Compose an Applicative[F] and a ContravariantMonoidal[G] into a ContravariantMonoidal[λ[α => F[G[α]]]].

    Example:

    scala> import cats.kernel.Comparison
    scala> import cats.implicits._
    
    // compares strings by alphabetical order
    scala> val alpha: Order[String] = Order[String]
    
    // compares strings by their length
    scala> val strLength: Order[String] = Order.by[String, Int](_.length)
    
    scala> val stringOrders: List[Order[String]] = List(alpha, strLength)
    
    // first comparison is with alpha order, second is with string length
    scala> stringOrders.map(o => o.comparison("abc", "de"))
    res0: List[Comparison] = List(LessThan, GreaterThan)
    
    scala> val le = Applicative[List].composeContravariantMonoidal[Order]
    
    // create Int orders that convert ints to strings and then use the string orders
    scala> val intOrders: List[Order[Int]] = le.contramap(stringOrders)(_.toString)
    
    // first comparison is with alpha order, second is with string length
    scala> intOrders.map(o => o.comparison(12, 3))
    res1: List[Comparison] = List(LessThan, GreaterThan)
    
    // create the `product` of the string order list and the int order list
    // `p` contains a list of the following orders:
    // 1. (alpha comparison on strings followed by alpha comparison on ints)
    // 2. (alpha comparison on strings followed by length comparison on ints)
    // 3. (length comparison on strings followed by alpha comparison on ints)
    // 4. (length comparison on strings followed by length comparison on ints)
    scala> val p: List[Order[(String, Int)]] = le.product(stringOrders, intOrders)
    
    scala> p.map(o => o.comparison(("abc", 12), ("def", 3)))
    res2: List[Comparison] = List(LessThan, LessThan, LessThan, GreaterThan)
    Definition Classes
    Applicative
  39. def composeFunctor[G[_]](implicit arg0: Functor[G]): Invariant[[α]F[G[α]]]
    Definition Classes
    Invariant
  40. final def eq(arg0: AnyRef): Boolean
    Definition Classes
    AnyRef
  41. def equals(arg0: Any): Boolean
    Definition Classes
    AnyRef → Any
  42. def finalize(): Unit
    Attributes
    protected[lang]
    Definition Classes
    AnyRef
    Annotations
    @throws( classOf[java.lang.Throwable] )
  43. def flatTap[A, B](fa: F[A])(f: (A) ⇒ F[B]): F[A]

    Apply a monadic function and discard the result while keeping the effect.

    Apply a monadic function and discard the result while keeping the effect.

    scala> import cats._, implicits._
    scala> Option(1).flatTap(_ => None)
    res0: Option[Int] = None
    scala> Option(1).flatTap(_ => Some("123"))
    res1: Option[Int] = Some(1)
    scala> def nCats(n: Int) = List.fill(n)("cat")
    nCats: (n: Int)List[String]
    scala> List[Int](0).flatTap(nCats)
    res2: List[Int] = List()
    scala> List[Int](4).flatTap(nCats)
    res3: List[Int] = List(4, 4, 4, 4)
    Definition Classes
    FlatMap
  44. def flatten[A](ffa: F[F[A]]): F[A]

    "flatten" a nested F of F structure into a single-layer F structure.

    "flatten" a nested F of F structure into a single-layer F structure.

    This is also commonly called join.

    Example:

    scala> import cats.Eval
    scala> import cats.implicits._
    
    scala> val nested: Eval[Eval[Int]] = Eval.now(Eval.now(3))
    scala> val flattened: Eval[Int] = nested.flatten
    scala> flattened.value
    res0: Int = 3
    Definition Classes
    FlatMap
  45. final def fmap[A, B](fa: F[A])(f: (A) ⇒ B): F[B]

    Alias for map, since map can't be injected as syntax if the implementing type already had a built-in .map method.

    Alias for map, since map can't be injected as syntax if the implementing type already had a built-in .map method.

    Example:

    scala> import cats.implicits._
    
    scala> val m: Map[Int, String] = Map(1 -> "hi", 2 -> "there", 3 -> "you")
    
    scala> m.fmap(_ ++ "!")
    res0: Map[Int,String] = Map(1 -> hi!, 2 -> there!, 3 -> you!)
    Definition Classes
    Functor
  46. def foreverM[A, B](fa: F[A]): F[B]

    Like an infinite loop of >> calls.

    Like an infinite loop of >> calls. This is most useful effect loops that you want to run forever in for instance a server.

    This will be an infinite loop, or it will return an F[Nothing].

    Be careful using this. For instance, a List of length k will produce a list of length k^n at iteration n. This means if k = 0, we return an empty list, if k = 1, we loop forever allocating single element lists, but if we have a k > 1, we will allocate exponentially increasing memory and very quickly OOM.

    Definition Classes
    FlatMap
    Annotations
    @noop()
  47. def fproduct[A, B](fa: F[A])(f: (A) ⇒ B): F[(A, B)]

    Tuple the values in fa with the result of applying a function with the value

    Tuple the values in fa with the result of applying a function with the value

    Example:

    scala> import cats.Functor
    scala> import cats.implicits.catsStdInstancesForOption
    
    scala> Functor[Option].fproduct(Option(42))(_.toString)
    res0: Option[(Int, String)] = Some((42,42))
    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 ifA[A](fcond: F[Boolean])(ifTrue: F[A], ifFalse: F[A]): F[A]

    An if-then-else lifted into the F context.

    An if-then-else lifted into the F context. This function combines the effects of the fcond condition and of the two branches, in the order in which they are given.

    The value of the result is, depending on the value of the condition, the value of the first argument, or the value of the second argument.

    Example:

    scala> import cats.implicits._
    
    scala> val b1: Option[Boolean] = Some(true)
    scala> val asInt1: Option[Int] = Apply[Option].ifA(b1)(Some(1), Some(0))
    scala> asInt1.get
    res0: Int = 1
    
    scala> val b2: Option[Boolean] = Some(false)
    scala> val asInt2: Option[Int] = Apply[Option].ifA(b2)(Some(1), Some(0))
    scala> asInt2.get
    res1: Int = 0
    
    scala> val b3: Option[Boolean] = Some(true)
    scala> val asInt3: Option[Int] = Apply[Option].ifA(b3)(Some(1), None)
    asInt2: Option[Int] = None
    Definition Classes
    Apply
    Annotations
    @noop()
  51. def ifF[A](fb: F[Boolean])(ifTrue: ⇒ A, ifFalse: ⇒ A): F[A]

    Lifts if to Functor

    Lifts if to Functor

    Example:

    scala> import cats.Functor
    scala> import cats.implicits.catsStdInstancesForList
    
    scala> Functor[List].ifF(List(true, false, false))(1, 0)
    res0: List[Int] = List(1, 0, 0)
    Definition Classes
    Functor
  52. def ifM[B](fa: F[Boolean])(ifTrue: ⇒ F[B], ifFalse: ⇒ F[B]): F[B]

    if lifted into monad.

    if lifted into monad.

    Definition Classes
    FlatMap
  53. def imap[A, B](fa: F[A])(f: (A) ⇒ B)(g: (B) ⇒ A): F[B]

    Transform an F[A] into an F[B] by providing a transformation from A to B and one from B to A.

    Transform an F[A] into an F[B] by providing a transformation from A to B and one from B to A.

    Example:

    scala> import cats.implicits._
    scala> import scala.concurrent.duration._
    scala> val durSemigroup: Semigroup[FiniteDuration] =
         | Invariant[Semigroup].imap(Semigroup[Long])(Duration.fromNanos)(_.toNanos)
    scala> durSemigroup.combine(2.seconds, 3.seconds)
    res1: FiniteDuration = 5 seconds
    Definition Classes
    FunctorInvariant
  54. final def isInstanceOf[T0]: Boolean
    Definition Classes
    Any
  55. def iterateForeverM[A, B](a: A)(f: (A) ⇒ F[A]): F[B]

    iterateForeverM is almost exclusively useful for effect types.

    iterateForeverM is almost exclusively useful for effect types. For instance, A may be some state, we may take the current state, run some effect to get a new state and repeat.

    Definition Classes
    FlatMap
    Annotations
    @noop()
  56. def iterateUntil[A](f: F[A])(p: (A) ⇒ Boolean): F[A]

    Execute an action repeatedly until its result satisfies the given predicate and return that result, discarding all others.

    Execute an action repeatedly until its result satisfies the given predicate and return that result, discarding all others.

    Definition Classes
    Monad
  57. def iterateUntilM[A](init: A)(f: (A) ⇒ F[A])(p: (A) ⇒ Boolean): F[A]

    Apply a monadic function iteratively until its result satisfies the given predicate and return that result.

    Apply a monadic function iteratively until its result satisfies the given predicate and return that result.

    Definition Classes
    Monad
  58. def iterateWhile[A](f: F[A])(p: (A) ⇒ Boolean): F[A]

    Execute an action repeatedly until its result fails to satisfy the given predicate and return that result, discarding all others.

    Execute an action repeatedly until its result fails to satisfy the given predicate and return that result, discarding all others.

    Definition Classes
    Monad
  59. def iterateWhileM[A](init: A)(f: (A) ⇒ F[A])(p: (A) ⇒ Boolean): F[A]

    Apply a monadic function iteratively until its result fails to satisfy the given predicate and return that result.

    Apply a monadic function iteratively until its result fails to satisfy the given predicate and return that result.

    Definition Classes
    Monad
  60. def lift[A, B](f: (A) ⇒ B): (F[A]) ⇒ F[B]

    Lift a function f to operate on Functors

    Lift a function f to operate on Functors

    Example:

    scala> import cats.Functor
    scala> import cats.implicits.catsStdInstancesForOption
    
    scala> val o = Option(42)
    scala> Functor[Option].lift((x: Int) => x + 10)(o)
    res0: Option[Int] = Some(52)
    Definition Classes
    Functor
  61. def map[A, B](fa: F[A])(f: (A) ⇒ B): F[B]
    Definition Classes
    MonadApplicativeFunctor
  62. def map10[A0, A1, A2, A3, A4, A5, A6, A7, A8, A9, Z](f0: F[A0], f1: F[A1], f2: F[A2], f3: F[A3], f4: F[A4], f5: F[A5], f6: F[A6], f7: F[A7], f8: F[A8], f9: F[A9])(f: (A0, A1, A2, A3, A4, A5, A6, A7, A8, A9) ⇒ Z): F[Z]

    Definition Classes
    ApplyArityFunctions
  63. def map11[A0, A1, A2, A3, A4, A5, A6, A7, A8, A9, A10, Z](f0: F[A0], f1: F[A1], f2: F[A2], f3: F[A3], f4: F[A4], f5: F[A5], f6: F[A6], f7: F[A7], f8: F[A8], f9: F[A9], f10: F[A10])(f: (A0, A1, A2, A3, A4, A5, A6, A7, A8, A9, A10) ⇒ Z): F[Z]

    Definition Classes
    ApplyArityFunctions
  64. def map12[A0, A1, A2, A3, A4, A5, A6, A7, A8, A9, A10, A11, Z](f0: F[A0], f1: F[A1], f2: F[A2], f3: F[A3], f4: F[A4], f5: F[A5], f6: F[A6], f7: F[A7], f8: F[A8], f9: F[A9], f10: F[A10], f11: F[A11])(f: (A0, A1, A2, A3, A4, A5, A6, A7, A8, A9, A10, A11) ⇒ Z): F[Z]

    Definition Classes
    ApplyArityFunctions
  65. def map13[A0, A1, A2, A3, A4, A5, A6, A7, A8, A9, A10, A11, A12, Z](f0: F[A0], f1: F[A1], f2: F[A2], f3: F[A3], f4: F[A4], f5: F[A5], f6: F[A6], f7: F[A7], f8: F[A8], f9: F[A9], f10: F[A10], f11: F[A11], f12: F[A12])(f: (A0, A1, A2, A3, A4, A5, A6, A7, A8, A9, A10, A11, A12) ⇒ Z): F[Z]

    Definition Classes
    ApplyArityFunctions
  66. def map14[A0, A1, A2, A3, A4, A5, A6, A7, A8, A9, A10, A11, A12, A13, Z](f0: F[A0], f1: F[A1], f2: F[A2], f3: F[A3], f4: F[A4], f5: F[A5], f6: F[A6], f7: F[A7], f8: F[A8], f9: F[A9], f10: F[A10], f11: F[A11], f12: F[A12], f13: F[A13])(f: (A0, A1, A2, A3, A4, A5, A6, A7, A8, A9, A10, A11, A12, A13) ⇒ Z): F[Z]

    Definition Classes
    ApplyArityFunctions
  67. def map15[A0, A1, A2, A3, A4, A5, A6, A7, A8, A9, A10, A11, A12, A13, A14, Z](f0: F[A0], f1: F[A1], f2: F[A2], f3: F[A3], f4: F[A4], f5: F[A5], f6: F[A6], f7: F[A7], f8: F[A8], f9: F[A9], f10: F[A10], f11: F[A11], f12: F[A12], f13: F[A13], f14: F[A14])(f: (A0, A1, A2, A3, A4, A5, A6, A7, A8, A9, A10, A11, A12, A13, A14) ⇒ Z): F[Z]

    Definition Classes
    ApplyArityFunctions
  68. def map16[A0, A1, A2, A3, A4, A5, A6, A7, A8, A9, A10, A11, A12, A13, A14, A15, Z](f0: F[A0], f1: F[A1], f2: F[A2], f3: F[A3], f4: F[A4], f5: F[A5], f6: F[A6], f7: F[A7], f8: F[A8], f9: F[A9], f10: F[A10], f11: F[A11], f12: F[A12], f13: F[A13], f14: F[A14], f15: F[A15])(f: (A0, A1, A2, A3, A4, A5, A6, A7, A8, A9, A10, A11, A12, A13, A14, A15) ⇒ Z): F[Z]

    Definition Classes
    ApplyArityFunctions
  69. def map17[A0, A1, A2, A3, A4, A5, A6, A7, A8, A9, A10, A11, A12, A13, A14, A15, A16, Z](f0: F[A0], f1: F[A1], f2: F[A2], f3: F[A3], f4: F[A4], f5: F[A5], f6: F[A6], f7: F[A7], f8: F[A8], f9: F[A9], f10: F[A10], f11: F[A11], f12: F[A12], f13: F[A13], f14: F[A14], f15: F[A15], f16: F[A16])(f: (A0, A1, A2, A3, A4, A5, A6, A7, A8, A9, A10, A11, A12, A13, A14, A15, A16) ⇒ Z): F[Z]

    Definition Classes
    ApplyArityFunctions
  70. def map18[A0, A1, A2, A3, A4, A5, A6, A7, A8, A9, A10, A11, A12, A13, A14, A15, A16, A17, Z](f0: F[A0], f1: F[A1], f2: F[A2], f3: F[A3], f4: F[A4], f5: F[A5], f6: F[A6], f7: F[A7], f8: F[A8], f9: F[A9], f10: F[A10], f11: F[A11], f12: F[A12], f13: F[A13], f14: F[A14], f15: F[A15], f16: F[A16], f17: F[A17])(f: (A0, A1, A2, A3, A4, A5, A6, A7, A8, A9, A10, A11, A12, A13, A14, A15, A16, A17) ⇒ Z): F[Z]

    Definition Classes
    ApplyArityFunctions
  71. def map19[A0, A1, A2, A3, A4, A5, A6, A7, A8, A9, A10, A11, A12, A13, A14, A15, A16, A17, A18, Z](f0: F[A0], f1: F[A1], f2: F[A2], f3: F[A3], f4: F[A4], f5: F[A5], f6: F[A6], f7: F[A7], f8: F[A8], f9: F[A9], f10: F[A10], f11: F[A11], f12: F[A12], f13: F[A13], f14: F[A14], f15: F[A15], f16: F[A16], f17: F[A17], f18: F[A18])(f: (A0, A1, A2, A3, A4, A5, A6, A7, A8, A9, A10, A11, A12, A13, A14, A15, A16, A17, A18) ⇒ Z): F[Z]

    Definition Classes
    ApplyArityFunctions
  72. def map2[A, B, Z](fa: F[A], fb: F[B])(f: (A, B) ⇒ Z): F[Z]

    Applies the pure (binary) function f to the effectful values fa and fb.

    Applies the pure (binary) function f to the effectful values fa and fb.

    map2 can be seen as a binary version of cats.Functor#map.

    Example:

    scala> import cats.implicits._
    
    scala> val someInt: Option[Int] = Some(3)
    scala> val noneInt: Option[Int] = None
    scala> val someLong: Option[Long] = Some(4L)
    scala> val noneLong: Option[Long] = None
    
    scala> Apply[Option].map2(someInt, someLong)((i, l) => i.toString + l.toString)
    res0: Option[String] = Some(34)
    
    scala> Apply[Option].map2(someInt, noneLong)((i, l) => i.toString + l.toString)
    res0: Option[String] = None
    
    scala> Apply[Option].map2(noneInt, noneLong)((i, l) => i.toString + l.toString)
    res0: Option[String] = None
    
    scala> Apply[Option].map2(noneInt, someLong)((i, l) => i.toString + l.toString)
    res0: Option[String] = None
    Definition Classes
    FlatMapApply
  73. def map20[A0, A1, A2, A3, A4, A5, A6, A7, A8, A9, A10, A11, A12, A13, A14, A15, A16, A17, A18, A19, Z](f0: F[A0], f1: F[A1], f2: F[A2], f3: F[A3], f4: F[A4], f5: F[A5], f6: F[A6], f7: F[A7], f8: F[A8], f9: F[A9], f10: F[A10], f11: F[A11], f12: F[A12], f13: F[A13], f14: F[A14], f15: F[A15], f16: F[A16], f17: F[A17], f18: F[A18], f19: F[A19])(f: (A0, A1, A2, A3, A4, A5, A6, A7, A8, A9, A10, A11, A12, A13, A14, A15, A16, A17, A18, A19) ⇒ Z): F[Z]

    Definition Classes
    ApplyArityFunctions
  74. def map21[A0, A1, A2, A3, A4, A5, A6, A7, A8, A9, A10, A11, A12, A13, A14, A15, A16, A17, A18, A19, A20, Z](f0: F[A0], f1: F[A1], f2: F[A2], f3: F[A3], f4: F[A4], f5: F[A5], f6: F[A6], f7: F[A7], f8: F[A8], f9: F[A9], f10: F[A10], f11: F[A11], f12: F[A12], f13: F[A13], f14: F[A14], f15: F[A15], f16: F[A16], f17: F[A17], f18: F[A18], f19: F[A19], f20: F[A20])(f: (A0, A1, A2, A3, A4, A5, A6, A7, A8, A9, A10, A11, A12, A13, A14, A15, A16, A17, A18, A19, A20) ⇒ Z): F[Z]

    Definition Classes
    ApplyArityFunctions
  75. def map22[A0, A1, A2, A3, A4, A5, A6, A7, A8, A9, A10, A11, A12, A13, A14, A15, A16, A17, A18, A19, A20, A21, Z](f0: F[A0], f1: F[A1], f2: F[A2], f3: F[A3], f4: F[A4], f5: F[A5], f6: F[A6], f7: F[A7], f8: F[A8], f9: F[A9], f10: F[A10], f11: F[A11], f12: F[A12], f13: F[A13], f14: F[A14], f15: F[A15], f16: F[A16], f17: F[A17], f18: F[A18], f19: F[A19], f20: F[A20], f21: F[A21])(f: (A0, A1, A2, A3, A4, A5, A6, A7, A8, A9, A10, A11, A12, A13, A14, A15, A16, A17, A18, A19, A20, A21) ⇒ Z): F[Z]

    Definition Classes
    ApplyArityFunctions
  76. def map2Eval[A, B, Z](fa: F[A], fb: Eval[F[B]])(f: (A, B) ⇒ Z): Eval[F[Z]]

    Similar to map2 but uses Eval to allow for laziness in the F[B] argument.

    Similar to map2 but uses Eval to allow for laziness in the F[B] argument. This can allow for "short-circuiting" of computations.

    NOTE: the default implementation of map2Eval does not short-circuit computations. For data structures that can benefit from laziness, Apply instances should override this method.

    In the following example, x.map2(bomb)(_ + _) would result in an error, but map2Eval "short-circuits" the computation. x is None and thus the result of bomb doesn't even need to be evaluated in order to determine that the result of map2Eval should be None.

    scala> import cats.{Eval, Later}
    scala> import cats.implicits._
    scala> val bomb: Eval[Option[Int]] = Later(sys.error("boom"))
    scala> val x: Option[Int] = None
    scala> x.map2Eval(bomb)(_ + _).value
    res0: Option[Int] = None
    Definition Classes
    Apply
  77. def map3[A0, A1, A2, Z](f0: F[A0], f1: F[A1], f2: F[A2])(f: (A0, A1, A2) ⇒ Z): F[Z]

    Definition Classes
    ApplyArityFunctions
  78. def map4[A0, A1, A2, A3, Z](f0: F[A0], f1: F[A1], f2: F[A2], f3: F[A3])(f: (A0, A1, A2, A3) ⇒ Z): F[Z]

    Definition Classes
    ApplyArityFunctions
  79. def map5[A0, A1, A2, A3, A4, Z](f0: F[A0], f1: F[A1], f2: F[A2], f3: F[A3], f4: F[A4])(f: (A0, A1, A2, A3, A4) ⇒ Z): F[Z]

    Definition Classes
    ApplyArityFunctions
  80. def map6[A0, A1, A2, A3, A4, A5, Z](f0: F[A0], f1: F[A1], f2: F[A2], f3: F[A3], f4: F[A4], f5: F[A5])(f: (A0, A1, A2, A3, A4, A5) ⇒ Z): F[Z]

    Definition Classes
    ApplyArityFunctions
  81. def map7[A0, A1, A2, A3, A4, A5, A6, Z](f0: F[A0], f1: F[A1], f2: F[A2], f3: F[A3], f4: F[A4], f5: F[A5], f6: F[A6])(f: (A0, A1, A2, A3, A4, A5, A6) ⇒ Z): F[Z]

    Definition Classes
    ApplyArityFunctions
  82. def map8[A0, A1, A2, A3, A4, A5, A6, A7, Z](f0: F[A0], f1: F[A1], f2: F[A2], f3: F[A3], f4: F[A4], f5: F[A5], f6: F[A6], f7: F[A7])(f: (A0, A1, A2, A3, A4, A5, A6, A7) ⇒ Z): F[Z]

    Definition Classes
    ApplyArityFunctions
  83. def map9[A0, A1, A2, A3, A4, A5, A6, A7, A8, Z](f0: F[A0], f1: F[A1], f2: F[A2], f3: F[A3], f4: F[A4], f5: F[A5], f6: F[A6], f7: F[A7], f8: F[A8])(f: (A0, A1, A2, A3, A4, A5, A6, A7, A8) ⇒ Z): F[Z]

    Definition Classes
    ApplyArityFunctions
  84. def mproduct[A, B](fa: F[A])(f: (A) ⇒ F[B]): F[(A, B)]

    Pair A with the result of function application.

    Pair A with the result of function application.

    Example:

    scala> import cats.implicits._
    scala> List("12", "34", "56").mproduct(_.toList)
    res0: List[(String, Char)] = List((12,1), (12,2), (34,3), (34,4), (56,5), (56,6))
    Definition Classes
    FlatMap
  85. final def ne(arg0: AnyRef): Boolean
    Definition Classes
    AnyRef
  86. final def notify(): Unit
    Definition Classes
    AnyRef
    Annotations
    @native()
  87. final def notifyAll(): Unit
    Definition Classes
    AnyRef
    Annotations
    @native()
  88. def point[A](a: A): F[A]

    point lifts any value into a Monoidal Functor.

    point lifts any value into a Monoidal Functor.

    Example:

    scala> import cats.implicits._
    
    scala> InvariantMonoidal[Option].point(10)
    res0: Option[Int] = Some(10)
    Definition Classes
    InvariantMonoidal
  89. def product[A, B](fa: F[A], fb: F[B]): F[(A, B)]

    Combine an F[A] and an F[B] into an F[(A, B)] that maintains the effects of both fa and fb.

    Combine an F[A] and an F[B] into an F[(A, B)] that maintains the effects of both fa and fb.

    Example:

    scala> import cats.implicits._
    
    scala> val noneInt: Option[Int] = None
    scala> val some3: Option[Int] = Some(3)
    scala> val noneString: Option[String] = None
    scala> val someFoo: Option[String] = Some("foo")
    
    scala> Semigroupal[Option].product(noneInt, noneString)
    res0: Option[(Int, String)] = None
    
    scala> Semigroupal[Option].product(noneInt, someFoo)
    res1: Option[(Int, String)] = None
    
    scala> Semigroupal[Option].product(some3, noneString)
    res2: Option[(Int, String)] = None
    
    scala> Semigroupal[Option].product(some3, someFoo)
    res3: Option[(Int, String)] = Some((3,foo))
    Definition Classes
    FlatMapApplySemigroupal
  90. def productL[A, B](fa: F[A])(fb: F[B]): F[A]

    Compose two actions, discarding any value produced by the second.

    Compose two actions, discarding any value produced by the second.

    Definition Classes
    FlatMapApply
    See also

    productR to discard the value of the first instead. Example:

    scala> import cats.implicits._
    scala> import cats.data.Validated
    scala> import Validated.{Valid, Invalid}
    
    scala> type ErrOr[A] = Validated[String, A]
    
    scala> val validInt: ErrOr[Int] = Valid(3)
    scala> val validBool: ErrOr[Boolean] = Valid(true)
    scala> val invalidInt: ErrOr[Int] = Invalid("Invalid int.")
    scala> val invalidBool: ErrOr[Boolean] = Invalid("Invalid boolean.")
    
    scala> Apply[ErrOr].productL(validInt)(validBool)
    res0: ErrOr[Int] = Valid(3)
    
    scala> Apply[ErrOr].productL(invalidInt)(validBool)
    res1: ErrOr[Int] = Invalid(Invalid int.)
    
    scala> Apply[ErrOr].productL(validInt)(invalidBool)
    res2: ErrOr[Int] = Invalid(Invalid boolean.)
    
    scala> Apply[ErrOr].productL(invalidInt)(invalidBool)
    res3: ErrOr[Int] = Invalid(Invalid int.Invalid boolean.)
  91. def productLEval[A, B](fa: F[A])(fb: Eval[F[B]]): F[A]

    Sequentially compose two actions, discarding any value produced by the second.

    Sequentially compose two actions, discarding any value produced by the second. This variant of productL also lets you define the evaluation strategy of the second action. For instance you can evaluate it only after the first action has finished:

    scala> import cats.Eval
    scala> import cats.implicits._
    scala> var count = 0
    scala> val fa: Option[Int] = Some(3)
    scala> def fb: Option[Unit] = Some(count += 1)
    scala> fa.productLEval(Eval.later(fb))
    res0: Option[Int] = Some(3)
    scala> assert(count == 1)
    scala> none[Int].productLEval(Eval.later(fb))
    res1: Option[Int] = None
    scala> assert(count == 1)
    Definition Classes
    FlatMap
  92. def productR[A, B](fa: F[A])(fb: F[B]): F[B]

    Compose two actions, discarding any value produced by the first.

    Compose two actions, discarding any value produced by the first.

    Definition Classes
    FlatMapApply
    See also

    productL to discard the value of the second instead. Example:

    scala> import cats.implicits._
    scala> import cats.data.Validated
    scala> import Validated.{Valid, Invalid}
    
    scala> type ErrOr[A] = Validated[String, A]
    
    scala> val validInt: ErrOr[Int] = Valid(3)
    scala> val validBool: ErrOr[Boolean] = Valid(true)
    scala> val invalidInt: ErrOr[Int] = Invalid("Invalid int.")
    scala> val invalidBool: ErrOr[Boolean] = Invalid("Invalid boolean.")
    
    scala> Apply[ErrOr].productR(validInt)(validBool)
    res0: ErrOr[Boolean] = Valid(true)
    
    scala> Apply[ErrOr].productR(invalidInt)(validBool)
    res1: ErrOr[Boolean] = Invalid(Invalid int.)
    
    scala> Apply[ErrOr].productR(validInt)(invalidBool)
    res2: ErrOr[Boolean] = Invalid(Invalid boolean.)
    
    scala> Apply[ErrOr].productR(invalidInt)(invalidBool)
    res3: ErrOr[Boolean] = Invalid(Invalid int.Invalid boolean.)
  93. def productREval[A, B](fa: F[A])(fb: Eval[F[B]]): F[B]

    Sequentially compose two actions, discarding any value produced by the first.

    Sequentially compose two actions, discarding any value produced by the first. This variant of productR also lets you define the evaluation strategy of the second action. For instance you can evaluate it only after the first action has finished:

    scala> import cats.Eval
    scala> import cats.implicits._
    scala> val fa: Option[Int] = Some(3)
    scala> def fb: Option[String] = Some("foo")
    scala> fa.productREval(Eval.later(fb))
    res0: Option[String] = Some(foo)
    Definition Classes
    FlatMap
  94. def replicateA[A](n: Int, fa: F[A]): F[List[A]]

    Given fa and n, apply fa n times to construct an F[List[A]] value.

    Given fa and n, apply fa n times to construct an F[List[A]] value.

    Example:

    scala> import cats.data.State
    
    scala> type Counter[A] = State[Int, A]
    scala> val getAndIncrement: Counter[Int] = State { i => (i + 1, i) }
    scala> val getAndIncrement5: Counter[List[Int]] =
         | Applicative[Counter].replicateA(5, getAndIncrement)
    scala> getAndIncrement5.run(0).value
    res0: (Int, List[Int]) = (5,List(0, 1, 2, 3, 4))
    Definition Classes
    Applicative
  95. final def synchronized[T0](arg0: ⇒ T0): T0
    Definition Classes
    AnyRef
  96. def tailRecM[A, B](a: A)(f: (A) ⇒ F[Either[A, B]]): F[B]

    Keeps calling f until a scala.util.Right[B] is returned.

    Keeps calling f until a scala.util.Right[B] is returned.

    Based on Phil Freeman's Stack Safety for Free.

    Implementations of this method should use constant stack space relative to f.

    Definition Classes
    StackSafeMonadFlatMap
  97. def toString(): String
    Definition Classes
    AnyRef → Any
  98. def tuple10[A0, A1, A2, A3, A4, A5, A6, A7, A8, A9, Z](f0: F[A0], f1: F[A1], f2: F[A2], f3: F[A3], f4: F[A4], f5: F[A5], f6: F[A6], f7: F[A7], f8: F[A8], f9: F[A9]): F[(A0, A1, A2, A3, A4, A5, A6, A7, A8, A9)]

    Definition Classes
    ApplyArityFunctions
  99. def tuple11[A0, A1, A2, A3, A4, A5, A6, A7, A8, A9, A10, Z](f0: F[A0], f1: F[A1], f2: F[A2], f3: F[A3], f4: F[A4], f5: F[A5], f6: F[A6], f7: F[A7], f8: F[A8], f9: F[A9], f10: F[A10]): F[(A0, A1, A2, A3, A4, A5, A6, A7, A8, A9, A10)]

    Definition Classes
    ApplyArityFunctions
  100. def tuple12[A0, A1, A2, A3, A4, A5, A6, A7, A8, A9, A10, A11, Z](f0: F[A0], f1: F[A1], f2: F[A2], f3: F[A3], f4: F[A4], f5: F[A5], f6: F[A6], f7: F[A7], f8: F[A8], f9: F[A9], f10: F[A10], f11: F[A11]): F[(A0, A1, A2, A3, A4, A5, A6, A7, A8, A9, A10, A11)]

    Definition Classes
    ApplyArityFunctions
  101. def tuple13[A0, A1, A2, A3, A4, A5, A6, A7, A8, A9, A10, A11, A12, Z](f0: F[A0], f1: F[A1], f2: F[A2], f3: F[A3], f4: F[A4], f5: F[A5], f6: F[A6], f7: F[A7], f8: F[A8], f9: F[A9], f10: F[A10], f11: F[A11], f12: F[A12]): F[(A0, A1, A2, A3, A4, A5, A6, A7, A8, A9, A10, A11, A12)]

    Definition Classes
    ApplyArityFunctions
  102. def tuple14[A0, A1, A2, A3, A4, A5, A6, A7, A8, A9, A10, A11, A12, A13, Z](f0: F[A0], f1: F[A1], f2: F[A2], f3: F[A3], f4: F[A4], f5: F[A5], f6: F[A6], f7: F[A7], f8: F[A8], f9: F[A9], f10: F[A10], f11: F[A11], f12: F[A12], f13: F[A13]): F[(A0, A1, A2, A3, A4, A5, A6, A7, A8, A9, A10, A11, A12, A13)]

    Definition Classes
    ApplyArityFunctions
  103. def tuple15[A0, A1, A2, A3, A4, A5, A6, A7, A8, A9, A10, A11, A12, A13, A14, Z](f0: F[A0], f1: F[A1], f2: F[A2], f3: F[A3], f4: F[A4], f5: F[A5], f6: F[A6], f7: F[A7], f8: F[A8], f9: F[A9], f10: F[A10], f11: F[A11], f12: F[A12], f13: F[A13], f14: F[A14]): F[(A0, A1, A2, A3, A4, A5, A6, A7, A8, A9, A10, A11, A12, A13, A14)]

    Definition Classes
    ApplyArityFunctions
  104. def tuple16[A0, A1, A2, A3, A4, A5, A6, A7, A8, A9, A10, A11, A12, A13, A14, A15, Z](f0: F[A0], f1: F[A1], f2: F[A2], f3: F[A3], f4: F[A4], f5: F[A5], f6: F[A6], f7: F[A7], f8: F[A8], f9: F[A9], f10: F[A10], f11: F[A11], f12: F[A12], f13: F[A13], f14: F[A14], f15: F[A15]): F[(A0, A1, A2, A3, A4, A5, A6, A7, A8, A9, A10, A11, A12, A13, A14, A15)]

    Definition Classes
    ApplyArityFunctions
  105. def tuple17[A0, A1, A2, A3, A4, A5, A6, A7, A8, A9, A10, A11, A12, A13, A14, A15, A16, Z](f0: F[A0], f1: F[A1], f2: F[A2], f3: F[A3], f4: F[A4], f5: F[A5], f6: F[A6], f7: F[A7], f8: F[A8], f9: F[A9], f10: F[A10], f11: F[A11], f12: F[A12], f13: F[A13], f14: F[A14], f15: F[A15], f16: F[A16]): F[(A0, A1, A2, A3, A4, A5, A6, A7, A8, A9, A10, A11, A12, A13, A14, A15, A16)]

    Definition Classes
    ApplyArityFunctions
  106. def tuple18[A0, A1, A2, A3, A4, A5, A6, A7, A8, A9, A10, A11, A12, A13, A14, A15, A16, A17, Z](f0: F[A0], f1: F[A1], f2: F[A2], f3: F[A3], f4: F[A4], f5: F[A5], f6: F[A6], f7: F[A7], f8: F[A8], f9: F[A9], f10: F[A10], f11: F[A11], f12: F[A12], f13: F[A13], f14: F[A14], f15: F[A15], f16: F[A16], f17: F[A17]): F[(A0, A1, A2, A3, A4, A5, A6, A7, A8, A9, A10, A11, A12, A13, A14, A15, A16, A17)]

    Definition Classes
    ApplyArityFunctions
  107. def tuple19[A0, A1, A2, A3, A4, A5, A6, A7, A8, A9, A10, A11, A12, A13, A14, A15, A16, A17, A18, Z](f0: F[A0], f1: F[A1], f2: F[A2], f3: F[A3], f4: F[A4], f5: F[A5], f6: F[A6], f7: F[A7], f8: F[A8], f9: F[A9], f10: F[A10], f11: F[A11], f12: F[A12], f13: F[A13], f14: F[A14], f15: F[A15], f16: F[A16], f17: F[A17], f18: F[A18]): F[(A0, A1, A2, A3, A4, A5, A6, A7, A8, A9, A10, A11, A12, A13, A14, A15, A16, A17, A18)]

    Definition Classes
    ApplyArityFunctions
  108. def tuple2[A, B](f1: F[A], f2: F[B]): F[(A, B)]
    Definition Classes
    ApplyArityFunctions
  109. def tuple20[A0, A1, A2, A3, A4, A5, A6, A7, A8, A9, A10, A11, A12, A13, A14, A15, A16, A17, A18, A19, Z](f0: F[A0], f1: F[A1], f2: F[A2], f3: F[A3], f4: F[A4], f5: F[A5], f6: F[A6], f7: F[A7], f8: F[A8], f9: F[A9], f10: F[A10], f11: F[A11], f12: F[A12], f13: F[A13], f14: F[A14], f15: F[A15], f16: F[A16], f17: F[A17], f18: F[A18], f19: F[A19]): F[(A0, A1, A2, A3, A4, A5, A6, A7, A8, A9, A10, A11, A12, A13, A14, A15, A16, A17, A18, A19)]

    Definition Classes
    ApplyArityFunctions
  110. def tuple21[A0, A1, A2, A3, A4, A5, A6, A7, A8, A9, A10, A11, A12, A13, A14, A15, A16, A17, A18, A19, A20, Z](f0: F[A0], f1: F[A1], f2: F[A2], f3: F[A3], f4: F[A4], f5: F[A5], f6: F[A6], f7: F[A7], f8: F[A8], f9: F[A9], f10: F[A10], f11: F[A11], f12: F[A12], f13: F[A13], f14: F[A14], f15: F[A15], f16: F[A16], f17: F[A17], f18: F[A18], f19: F[A19], f20: F[A20]): F[(A0, A1, A2, A3, A4, A5, A6, A7, A8, A9, A10, A11, A12, A13, A14, A15, A16, A17, A18, A19, A20)]

    Definition Classes
    ApplyArityFunctions
  111. def tuple22[A0, A1, A2, A3, A4, A5, A6, A7, A8, A9, A10, A11, A12, A13, A14, A15, A16, A17, A18, A19, A20, A21, Z](f0: F[A0], f1: F[A1], f2: F[A2], f3: F[A3], f4: F[A4], f5: F[A5], f6: F[A6], f7: F[A7], f8: F[A8], f9: F[A9], f10: F[A10], f11: F[A11], f12: F[A12], f13: F[A13], f14: F[A14], f15: F[A15], f16: F[A16], f17: F[A17], f18: F[A18], f19: F[A19], f20: F[A20], f21: F[A21]): F[(A0, A1, A2, A3, A4, A5, A6, A7, A8, A9, A10, A11, A12, A13, A14, A15, A16, A17, A18, A19, A20, A21)]

    Definition Classes
    ApplyArityFunctions
  112. def tuple3[A0, A1, A2, Z](f0: F[A0], f1: F[A1], f2: F[A2]): F[(A0, A1, A2)]

    Definition Classes
    ApplyArityFunctions
  113. def tuple4[A0, A1, A2, A3, Z](f0: F[A0], f1: F[A1], f2: F[A2], f3: F[A3]): F[(A0, A1, A2, A3)]

    Definition Classes
    ApplyArityFunctions
  114. def tuple5[A0, A1, A2, A3, A4, Z](f0: F[A0], f1: F[A1], f2: F[A2], f3: F[A3], f4: F[A4]): F[(A0, A1, A2, A3, A4)]

    Definition Classes
    ApplyArityFunctions
  115. def tuple6[A0, A1, A2, A3, A4, A5, Z](f0: F[A0], f1: F[A1], f2: F[A2], f3: F[A3], f4: F[A4], f5: F[A5]): F[(A0, A1, A2, A3, A4, A5)]

    Definition Classes
    ApplyArityFunctions
  116. def tuple7[A0, A1, A2, A3, A4, A5, A6, Z](f0: F[A0], f1: F[A1], f2: F[A2], f3: F[A3], f4: F[A4], f5: F[A5], f6: F[A6]): F[(A0, A1, A2, A3, A4, A5, A6)]

    Definition Classes
    ApplyArityFunctions
  117. def tuple8[A0, A1, A2, A3, A4, A5, A6, A7, Z](f0: F[A0], f1: F[A1], f2: F[A2], f3: F[A3], f4: F[A4], f5: F[A5], f6: F[A6], f7: F[A7]): F[(A0, A1, A2, A3, A4, A5, A6, A7)]

    Definition Classes
    ApplyArityFunctions
  118. def tuple9[A0, A1, A2, A3, A4, A5, A6, A7, A8, Z](f0: F[A0], f1: F[A1], f2: F[A2], f3: F[A3], f4: F[A4], f5: F[A5], f6: F[A6], f7: F[A7], f8: F[A8]): F[(A0, A1, A2, A3, A4, A5, A6, A7, A8)]

    Definition Classes
    ApplyArityFunctions
  119. def tupleLeft[A, B](fa: F[A], b: B): F[(B, A)]

    Tuples the A value in F[A] with the supplied B value, with the B value on the left.

    Tuples the A value in F[A] with the supplied B value, with the B value on the left.

    Example:

    scala> import scala.collection.immutable.Queue
    scala> import cats.Functor
    scala> import cats.implicits.catsStdInstancesForQueue
    
    scala> Functor[Queue].tupleLeft(Queue("hello", "world"), 42)
    res0: scala.collection.immutable.Queue[(Int, String)] = Queue((42,hello), (42,world))
    Definition Classes
    Functor
  120. def tupleRight[A, B](fa: F[A], b: B): F[(A, B)]

    Tuples the A value in F[A] with the supplied B value, with the B value on the right.

    Tuples the A value in F[A] with the supplied B value, with the B value on the right.

    Example:

    scala> import scala.collection.immutable.Queue
    scala> import cats.Functor
    scala> import cats.implicits.catsStdInstancesForQueue
    
    scala> Functor[Queue].tupleRight(Queue("hello", "world"), 42)
    res0: scala.collection.immutable.Queue[(String, Int)] = Queue((hello,42), (world,42))
    Definition Classes
    Functor
  121. def unit: F[Unit]

    Returns an F[Unit] value, equivalent with pure(()).

    Returns an F[Unit] value, equivalent with pure(()).

    A useful shorthand, also allowing implementations to optimize the returned reference (e.g. it can be a val).

    Example:

    scala> import cats.implicits._
    
    scala> Applicative[Option].unit
    res0: Option[Unit] = Some(())
    Definition Classes
    ApplicativeInvariantMonoidal
  122. def unlessA[A](cond: Boolean)(f: ⇒ F[A]): F[Unit]

    Returns the given argument (mapped to Unit) if cond is false, otherwise, unit lifted into F.

    Returns the given argument (mapped to Unit) if cond is false, otherwise, unit lifted into F.

    Example:

    scala> import cats.implicits._
    
    scala> Applicative[List].unlessA(true)(List(1, 2, 3))
    res0: List[Unit] = List(())
    
    scala> Applicative[List].unlessA(false)(List(1, 2, 3))
    res1: List[Unit] = List((), (), ())
    
    scala> Applicative[List].unlessA(true)(List.empty[Int])
    res2: List[Unit] = List(())
    
    scala> Applicative[List].unlessA(false)(List.empty[Int])
    res3: List[Unit] = List()
    Definition Classes
    Applicative
  123. def untilDefinedM[A](foa: F[Option[A]]): F[A]

    This repeats an F until we get defined values.

    This repeats an F until we get defined values. This can be useful for polling type operations on State (or RNG) Monads, or in effect monads.

    Definition Classes
    FlatMap
    Annotations
    @noop()
  124. def untilM[G[_], A](f: F[A])(cond: ⇒ F[Boolean])(implicit G: Alternative[G]): F[G[A]]

    Execute an action repeatedly until the Boolean condition returns true.

    Execute an action repeatedly until the Boolean condition returns true. The condition is evaluated after the loop body. Collects results into an arbitrary Alternative value, such as a Vector. This implementation uses append on each evaluation result, so avoid data structures with non-constant append performance, e.g. List.

    Definition Classes
    Monad
  125. def untilM_[A](f: F[A])(cond: ⇒ F[Boolean]): F[Unit]

    Execute an action repeatedly until the Boolean condition returns true.

    Execute an action repeatedly until the Boolean condition returns true. The condition is evaluated after the loop body. Discards results.

    Definition Classes
    Monad
  126. def unzip[A, B](fab: F[(A, B)]): (F[A], F[B])

    Un-zips an F[(A, B)] consisting of element pairs or Tuple2 into two separate F's tupled.

    Un-zips an F[(A, B)] consisting of element pairs or Tuple2 into two separate F's tupled.

    NOTE: Check for effect duplication, possibly memoize before

    scala> import cats.Functor
    scala> import cats.implicits.catsStdInstancesForList
    
    scala> Functor[List].unzip(List((1,2), (3, 4)))
    res0: (List[Int], List[Int]) = (List(1, 3),List(2, 4))
    Definition Classes
    Functor
    Annotations
    @noop()
  127. def void[A](fa: F[A]): F[Unit]

    Empty the fa of the values, preserving the structure

    Empty the fa of the values, preserving the structure

    Example:

    scala> import cats.Functor
    scala> import cats.implicits.catsStdInstancesForList
    
    scala> Functor[List].void(List(1,2,3))
    res0: List[Unit] = List((), (), ())
    Definition Classes
    Functor
  128. final def wait(): Unit
    Definition Classes
    AnyRef
    Annotations
    @throws( ... )
  129. final def wait(arg0: Long, arg1: Int): Unit
    Definition Classes
    AnyRef
    Annotations
    @throws( ... )
  130. final def wait(arg0: Long): Unit
    Definition Classes
    AnyRef
    Annotations
    @throws( ... ) @native()
  131. def whenA[A](cond: Boolean)(f: ⇒ F[A]): F[Unit]

    Returns the given argument (mapped to Unit) if cond is true, otherwise, unit lifted into F.

    Returns the given argument (mapped to Unit) if cond is true, otherwise, unit lifted into F.

    Example:

    scala> import cats.implicits._
    
    scala> Applicative[List].whenA(true)(List(1, 2, 3))
    res0: List[Unit] = List((), (), ())
    
    scala> Applicative[List].whenA(false)(List(1, 2, 3))
    res1: List[Unit] = List(())
    
    scala> Applicative[List].whenA(true)(List.empty[Int])
    res2: List[Unit] = List()
    
    scala> Applicative[List].whenA(false)(List.empty[Int])
    res3: List[Unit] = List(())
    Definition Classes
    Applicative
  132. def whileM[G[_], A](p: F[Boolean])(body: ⇒ F[A])(implicit G: Alternative[G]): F[G[A]]

    Execute an action repeatedly as long as the given Boolean expression returns true.

    Execute an action repeatedly as long as the given Boolean expression returns true. The condition is evaluated before the loop body. Collects the results into an arbitrary Alternative value, such as a Vector. This implementation uses append on each evaluation result, so avoid data structures with non-constant append performance, e.g. List.

    Definition Classes
    Monad
  133. def whileM_[A](p: F[Boolean])(body: ⇒ F[A]): F[Unit]

    Execute an action repeatedly as long as the given Boolean expression returns true.

    Execute an action repeatedly as long as the given Boolean expression returns true. The condition is evaluated before the loop body. Discards results.

    Definition Classes
    Monad
  134. def widen[A, B >: A](fa: F[A]): F[B]

    Lifts natural subtyping covariance of covariant Functors.

    Lifts natural subtyping covariance of covariant Functors.

    NOTE: In certain (perhaps contrived) situations that rely on universal equality this can result in a ClassCastException, because it is implemented as a type cast. It could be implemented as map(identity), but according to the functor laws, that should be equal to fa, and a type cast is often much more performant. See this example of widen creating a ClassCastException.

    Example:

    scala> import cats.Functor
    scala> import cats.implicits.catsStdInstancesForOption
    
    scala> val s = Some(42)
    scala> Functor[Option].widen(s)
    res0: Option[Int] = Some(42)
    Definition Classes
    Functor

Inherited from Monad[F]

Inherited from Applicative[F]

Inherited from InvariantMonoidal[F]

Inherited from FlatMap[F]

Inherited from Apply[F]

Inherited from ApplyArityFunctions[F]

Inherited from InvariantSemigroupal[F]

Inherited from Semigroupal[F]

Inherited from Functor[F]

Inherited from Invariant[F]

Inherited from Serializable

Inherited from Serializable

Inherited from AnyRef

Inherited from Any

Ungrouped

ap arity

Higher-arity ap methods

map arity

Higher-arity map methods

tuple arity

Higher-arity tuple methods