Packages

trait Foldable[F[_]] extends FoldableParent[F]

A type parameter implying the ability to extract zero or more values of that type.

Self Type
Foldable[F]
Source
Foldable.scala
Linear Supertypes
FoldableParent[F], AnyRef, Any
Known Subclasses
FromFoldMap, FromFoldr, Foldable1, IsomorphismFoldable, IsomorphismFoldable1, IsomorphismTraverse, IsomorphismTraverse1, Traverse, Traverse1
Ordering
  1. Alphabetic
  2. By Inheritance
Inherited
  1. Foldable
  2. FoldableParent
  3. AnyRef
  4. Any
  1. Hide All
  2. Show All
Visibility
  1. Public
  2. Protected

Type Members

  1. trait FoldableLaw extends AnyRef

Abstract Value Members

  1. abstract def foldMap[A, B](fa: F[A])(f: (A) => B)(implicit F: Monoid[B]): B

    Map each element of the structure to a scalaz.Monoid, and combine the results.

  2. abstract def foldRight[A, B](fa: F[A], z: => B)(f: (A, => B) => B): B

    Right-associative fold of a structure.

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 all[A](fa: F[A])(p: (A) => Boolean): Boolean

    Whether all As in fa yield true from p.

  5. def allM[G[_], A](fa: F[A])(p: (A) => G[Boolean])(implicit G: Monad[G]): G[Boolean]

    all with monadic traversal.

  6. def any[A](fa: F[A])(p: (A) => Boolean): Boolean

    Whether any As in fa yield true from p.

  7. def anyM[G[_], A](fa: F[A])(p: (A) => G[Boolean])(implicit G: Monad[G]): G[Boolean]

    any with monadic traversal.

  8. final def asInstanceOf[T0]: T0
    Definition Classes
    Any
  9. def bicompose[G[_, _]](implicit arg0: Bifoldable[G]): Bifoldable[[α, β]F[G[α, β]]]

    The composition of Foldable F and Bifoldable G, [x, y]F[G[x, y]], is a Bifoldable

  10. def clone(): AnyRef
    Attributes
    protected[lang]
    Definition Classes
    AnyRef
    Annotations
    @throws(classOf[java.lang.CloneNotSupportedException]) @native()
  11. def collapse[X[_], A](x: F[A])(implicit A: ApplicativePlus[X]): X[A]
  12. def compose[G[_]](implicit G0: Foldable[G]): Foldable[[α]F[G[α]]]

    The composition of Foldables F and G, [x]F[G[x]], is a Foldable

  13. final def count[A](fa: F[A]): Int

    Alias for length.

  14. def distinct[A](fa: F[A])(implicit A: Order[A]): IList[A]

    O(n log n) complexity

  15. def distinctBy[A, B](fa: F[A])(f: (A) => B)(implicit arg0: Equal[B]): IList[A]
    Definition Classes
    FoldableParent
  16. def distinctE[A](fa: F[A])(implicit A: Equal[A]): IList[A]

    O(n2) complexity

  17. def element[A](fa: F[A], a: A)(implicit arg0: Equal[A]): Boolean

    Whether a is an element of fa.

  18. def empty[A](fa: F[A]): Boolean

    Deforested alias for toStream(fa).isEmpty.

  19. final def eq(arg0: AnyRef): Boolean
    Definition Classes
    AnyRef
  20. def equals(arg0: AnyRef): Boolean
    Definition Classes
    AnyRef → Any
  21. def extrema[A](fa: F[A])(implicit arg0: Order[A]): Option[(A, A)]

    The smallest and largest elements of fa or None if fa is empty

    The smallest and largest elements of fa or None if fa is empty

    Definition Classes
    FoldableParent
  22. def extremaBy[A, B](fa: F[A])(f: (A) => B)(implicit arg0: Order[B]): Option[(A, A)]

    The elements (amin, amax) of fa which yield the smallest and largest values of f(a), respectively, or None if fa is empty

    The elements (amin, amax) of fa which yield the smallest and largest values of f(a), respectively, or None if fa is empty

    Definition Classes
    FoldableParent
  23. def extremaOf[A, B](fa: F[A])(f: (A) => B)(implicit arg0: Order[B]): Option[(B, B)]

    The smallest and largest values of f(a) for each element a of fa , or None if fa is empty

    The smallest and largest values of f(a) for each element a of fa , or None if fa is empty

    Definition Classes
    FoldableParent
  24. def filterLength[A](fa: F[A])(f: (A) => Boolean): Int
    Definition Classes
    FoldableParent
  25. def finalize(): Unit
    Attributes
    protected[lang]
    Definition Classes
    AnyRef
    Annotations
    @throws(classOf[java.lang.Throwable])
  26. def findLeft[A](fa: F[A])(f: (A) => Boolean): Option[A]
  27. final def findMapM[M[_], A, B](fa: F[A])(f: (A) => M[Option[B]])(implicit arg0: Monad[M]): M[Option[B]]

    map elements in a Foldable with a monadic function and return the first element that is mapped successfully

  28. def findRight[A](fa: F[A])(f: (A) => Boolean): Option[A]
  29. def fold[M](t: F[M])(implicit arg0: Monoid[M]): M

    Combine the elements of a structure using a monoid.

  30. def fold1Opt[A](fa: F[A])(implicit arg0: Semigroup[A]): Option[A]

    Like fold but returning None if the foldable is empty and Some otherwise

    Like fold but returning None if the foldable is empty and Some otherwise

    Definition Classes
    FoldableParent
  31. def foldLeft[A, B](fa: F[A], z: B)(f: (B, A) => B): B

    Left-associative fold of a structure.

  32. def foldLeft1Opt[A](fa: F[A])(f: (A, A) => A): Option[A]
  33. def foldLeftM[G[_], A, B](fa: F[A], z: B)(f: (B, A) => G[B])(implicit M: Monad[G]): G[B]

    Left-associative, monadic fold of a structure.

  34. def foldMap1Opt[A, B](fa: F[A])(f: (A) => B)(implicit F: Semigroup[B]): Option[B]

    As foldMap but returning None if the foldable is empty and Some otherwise

  35. def foldMapLeft1Opt[A, B](fa: F[A])(z: (A) => B)(f: (B, A) => B): Option[B]
  36. def foldMapM[G[_], A, B](fa: F[A])(f: (A) => G[B])(implicit B: Monoid[B], G: Monad[G]): G[B]

    Specialization of foldRightM when B has a Monoid.

  37. def foldMapRight1Opt[A, B](fa: F[A])(z: (A) => B)(f: (A, => B) => B): Option[B]
  38. def foldRight1Opt[A](fa: F[A])(f: (A, => A) => A): Option[A]
  39. def foldRightM[G[_], A, B](fa: F[A], z: => B)(f: (A, => B) => G[B])(implicit M: Monad[G]): G[B]

    Right-associative, monadic fold of a structure.

  40. def foldableLaw: FoldableLaw
  41. val foldableSyntax: FoldableSyntax[F]
  42. final def foldl[A, B](fa: F[A], z: B)(f: (B) => (A) => B): B

    Curried version of foldLeft

  43. def foldl1Opt[A](fa: F[A])(f: (A) => (A) => A): Option[A]
  44. final def foldlM[G[_], A, B](fa: F[A], z: => B)(f: (B) => (A) => G[B])(implicit M: Monad[G]): G[B]

    Curried version of foldLeftM

  45. final def foldr[A, B](fa: F[A], z: => B)(f: (A) => (=> B) => B): B

    Curried version of foldRight

  46. def foldr1Opt[A](fa: F[A])(f: (A) => (=> A) => A): Option[A]
  47. final def foldrM[G[_], A, B](fa: F[A], z: => B)(f: (A) => (=> B) => G[B])(implicit M: Monad[G]): G[B]

    Curried version of foldRightM

  48. final def getClass(): Class[_ <: AnyRef]
    Definition Classes
    AnyRef → Any
    Annotations
    @native()
  49. def hashCode(): Int
    Definition Classes
    AnyRef → Any
    Annotations
    @native()
  50. def index[A](fa: F[A], i: Int): Option[A]

    returns

    the element at index i in a Some, or None if the given index falls outside of the range

  51. def indexOr[A](fa: F[A], default: => A, i: Int): A

    returns

    the element at index i, or default if the given index falls outside of the range

  52. def intercalate[A](fa: F[A], a: A)(implicit A: Monoid[A]): A

    Insert an A between every A, yielding the sum.

  53. final def isInstanceOf[T0]: Boolean
    Definition Classes
    Any
  54. def length[A](fa: F[A]): Int

    Deforested alias for toStream(fa).size.

  55. def longDigits[A](fa: F[A])(implicit d: <:<[A, Digit]): Long
  56. def maximum[A](fa: F[A])(implicit arg0: Order[A]): Option[A]

    The greatest element of fa, or None if fa is empty.

  57. def maximumBy[A, B](fa: F[A])(f: (A) => B)(implicit arg0: Order[B]): Option[A]

    The element a of fa which yields the greatest value of f(a), or None if fa is empty.

  58. def maximumOf[A, B](fa: F[A])(f: (A) => B)(implicit arg0: Order[B]): Option[B]

    The greatest value of f(a) for each element a of fa, or None if fa is empty.

  59. def minimum[A](fa: F[A])(implicit arg0: Order[A]): Option[A]

    The smallest element of fa, or None if fa is empty.

  60. def minimumBy[A, B](fa: F[A])(f: (A) => B)(implicit arg0: Order[B]): Option[A]

    The element a of fa which yields the smallest value of f(a), or None if fa is empty.

  61. def minimumOf[A, B](fa: F[A])(f: (A) => B)(implicit arg0: Order[B]): Option[B]

    The smallest value of f(a) for each element a of fa, or None if fa is empty.

  62. def msuml[G[_], A](fa: F[G[A]])(implicit G: PlusEmpty[G]): G[A]
  63. def msumlU[GA](fa: F[GA])(implicit G: Unapply[PlusEmpty, GA]): M[A]
    Definition Classes
    FoldableParent
  64. final def ne(arg0: AnyRef): Boolean
    Definition Classes
    AnyRef
  65. final def notify(): Unit
    Definition Classes
    AnyRef
    Annotations
    @native()
  66. final def notifyAll(): Unit
    Definition Classes
    AnyRef
    Annotations
    @native()
  67. def product[G[_]](implicit G0: Foldable[G]): Foldable[[α](F[α], G[α])]

    The product of Foldables F and G, [x](F[x], G[x]]), is a Foldable

  68. def product0[G[_]](implicit G0: Foldable1[G]): Foldable1[[α](F[α], G[α])]

    The product of Foldable F and Foldable1 G, [x](F[x], G[x]]), is a Foldable1

  69. def selectSplit[A](fa: F[A])(p: (A) => Boolean): List[NonEmptyList[A]]

    Selects groups of elements that satisfy p and discards others.

  70. def sequenceF_[M[_], A](ffa: F[Free[M, A]]): Free[M, Unit]

    sequence_ for Free.

    sequence_ for Free. collapses into a single Free *

  71. def sequenceS_[S, A](fga: F[State[S, A]]): State[S, Unit]

    sequence_ specialized to State *

  72. def sequence_[M[_], A](fa: F[M[A]])(implicit a: Applicative[M]): M[Unit]

    Strict sequencing in an applicative functor M that ignores the value in fa.

  73. def splitBy[A, B](fa: F[A])(f: (A) => B)(implicit arg0: Equal[B]): IList[(B, NonEmptyList[A])]

    Splits the elements into groups that produce the same result by a function f.

    Splits the elements into groups that produce the same result by a function f.

    Definition Classes
    FoldableParent
  74. def splitByRelation[A](fa: F[A])(r: (A, A) => Boolean): IList[NonEmptyList[A]]

    Splits into groups of elements that are transitively dependant by a relation r.

    Splits into groups of elements that are transitively dependant by a relation r.

    Definition Classes
    FoldableParent
  75. def splitWith[A](fa: F[A])(p: (A) => Boolean): List[NonEmptyList[A]]

    Splits the elements into groups that alternatively satisfy and don't satisfy the predicate p.

  76. def suml[A](fa: F[A])(implicit A: Monoid[A]): A
  77. def suml1Opt[A](fa: F[A])(implicit A: Semigroup[A]): Option[A]
  78. def sumr[A](fa: F[A])(implicit A: Monoid[A]): A
  79. def sumr1Opt[A](fa: F[A])(implicit A: Semigroup[A]): Option[A]
  80. final def synchronized[T0](arg0: => T0): T0
    Definition Classes
    AnyRef
  81. def toEphemeralStream[A](fa: F[A]): EphemeralStream[A]
  82. def toIList[A](fa: F[A]): IList[A]
  83. def toList[A](fa: F[A]): List[A]
  84. def toSet[A](fa: F[A]): Set[A]
  85. def toStream[A](fa: F[A]): Stream[A]
  86. def toString(): String
    Definition Classes
    AnyRef → Any
  87. def toVector[A](fa: F[A]): Vector[A]
  88. def traverseS_[S, A, B](fa: F[A])(f: (A) => State[S, B]): State[S, Unit]

    traverse_ specialized to State *

  89. final def traverseU_[A, GB](fa: F[A])(f: (A) => GB)(implicit G: Unapply[Applicative, GB]): M[Unit]

    A version of traverse_ that infers the type constructor M.

  90. def traverse_[M[_], A, B](fa: F[A])(f: (A) => M[B])(implicit a: Applicative[M]): M[Unit]

    Strict traversal in an applicative functor M that ignores the result of f.

  91. final def wait(): Unit
    Definition Classes
    AnyRef
    Annotations
    @throws(classOf[java.lang.InterruptedException])
  92. final def wait(arg0: Long, arg1: Int): Unit
    Definition Classes
    AnyRef
    Annotations
    @throws(classOf[java.lang.InterruptedException])
  93. final def wait(arg0: Long): Unit
    Definition Classes
    AnyRef
    Annotations
    @throws(classOf[java.lang.InterruptedException]) @native()

Deprecated Value Members

  1. def to[A, G[_]](fa: F[A])(implicit c: CanBuildFrom[Nothing, A, G[A]]): G[A]

    Annotations
    @deprecated
    Deprecated

    (Since version 7.2.22) removed in scalaz 7.3

    Exceptions thrown

    NoSuchMethodException if Scala 2.13 or later

Inherited from FoldableParent[F]

Inherited from AnyRef

Inherited from Any

Ungrouped