Packages

t

scalaz.Foldable

FromFoldr

trait FromFoldr[F[_]] extends Foldable[F]

Template trait to define Foldable in terms of foldr

Example:

new Foldable[Option] with Foldable.FromFoldr[Option] {
  def foldr[A, B](fa: Option[A], z: B)(f: (A) => (=> B) => B) = fa match {
    case Some(a) => f(a)(z)
    case None => z
  }
}
Source
Foldable.scala
Linear Supertypes
Foldable[F], FoldableParent[F], AnyRef, Any
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Inherited
  1. FromFoldr
  2. Foldable
  3. FoldableParent
  4. AnyRef
  5. Any
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Visibility
  1. Public
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Type Members

  1. trait FoldableLaw extends AnyRef
    Definition Classes
    Foldable

Abstract Value Members

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

    Right-associative fold of a structure.

    Right-associative fold of a structure.

    Definition Classes
    Foldable

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.

    Whether all As in fa yield true from p.

    Definition Classes
    Foldable
  5. def allM[G[_], A](fa: F[A])(p: (A) ⇒ G[Boolean])(implicit G: Monad[G]): G[Boolean]

    all with monadic traversal.

    all with monadic traversal.

    Definition Classes
    Foldable
  6. def any[A](fa: F[A])(p: (A) ⇒ Boolean): Boolean

    Whether any As in fa yield true from p.

    Whether any As in fa yield true from p.

    Definition Classes
    Foldable
  7. def anyM[G[_], A](fa: F[A])(p: (A) ⇒ G[Boolean])(implicit G: Monad[G]): G[Boolean]

    any with monadic traversal.

    any with monadic traversal.

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

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

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

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

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

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

    Alias for length.

    Alias for length.

    Definition Classes
    Foldable
  14. def element[A](fa: F[A], a: A)(implicit arg0: Equal[A]): Boolean

    Whether a is an element of fa.

    Whether a is an element of fa.

    Definition Classes
    Foldable
  15. def empty[A](fa: F[A]): Boolean

    Deforested alias for toStream(fa).isEmpty.

    Deforested alias for toStream(fa).isEmpty.

    Definition Classes
    Foldable
  16. final def eq(arg0: AnyRef): Boolean
    Definition Classes
    AnyRef
  17. def equals(arg0: Any): Boolean
    Definition Classes
    AnyRef → Any
  18. 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
  19. 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
  20. 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
  21. def filterLength[A](fa: F[A])(f: (A) ⇒ Boolean): Int
    Definition Classes
    FoldableParent
  22. def finalize(): Unit
    Attributes
    protected[java.lang]
    Definition Classes
    AnyRef
    Annotations
    @throws( classOf[java.lang.Throwable] )
  23. def findLeft[A](fa: F[A])(f: (A) ⇒ Boolean): Option[A]
    Definition Classes
    FoldableParent
  24. def findMapM[M[_], A, B](fa: F[A])(f: (A) ⇒ M[Option[B]])(implicit arg0: Monad[M]): M[Option[B]]
    Definition Classes
    FoldableParent
  25. def findRight[A](fa: F[A])(f: (A) ⇒ Boolean): Option[A]
    Definition Classes
    FoldableParent
  26. def fold[M](t: F[M])(implicit arg0: Monoid[M]): M

    Combine the elements of a structure using a monoid.

    Combine the elements of a structure using a monoid.

    Definition Classes
    Foldable
  27. 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
  28. def foldLeft[A, B](fa: F[A], z: B)(f: (B, A) ⇒ B): B

    Left-associative fold of a structure.

    Left-associative fold of a structure.

    Definition Classes
    Foldable
  29. def foldLeft1Opt[A](fa: F[A])(f: (A, A) ⇒ A): Option[A]
    Definition Classes
    Foldable
  30. 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.

    Left-associative, monadic fold of a structure.

    Definition Classes
    Foldable
  31. 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.

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

    Definition Classes
    FromFoldr → Foldable
  32. 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

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

    Definition Classes
    Foldable
  33. def foldMapLeft1Opt[A, B](fa: F[A])(z: (A) ⇒ B)(f: (B, A) ⇒ B): Option[B]
    Definition Classes
    Foldable
  34. 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.

    Specialization of foldRightM when B has a Monoid.

    Definition Classes
    Foldable
  35. def foldMapRight1Opt[A, B](fa: F[A])(z: (A) ⇒ B)(f: (A, ⇒ B) ⇒ B): Option[B]
    Definition Classes
    Foldable
  36. def foldRight1Opt[A](fa: F[A])(f: (A, ⇒ A) ⇒ A): Option[A]
    Definition Classes
    Foldable
  37. 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.

    Right-associative, monadic fold of a structure.

    Definition Classes
    Foldable
  38. def foldableLaw: FoldableLaw
    Definition Classes
    Foldable
  39. val foldableSyntax: FoldableSyntax[F]
    Definition Classes
    Foldable
  40. final def foldl[A, B](fa: F[A], z: B)(f: (B) ⇒ (A) ⇒ B): B

    Curried version of foldLeft

    Curried version of foldLeft

    Definition Classes
    Foldable
  41. def foldl1Opt[A](fa: F[A])(f: (A) ⇒ (A) ⇒ A): Option[A]
    Definition Classes
    Foldable
  42. 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

    Curried version of foldLeftM

    Definition Classes
    Foldable
  43. final def foldr[A, B](fa: F[A], z: ⇒ B)(f: (A) ⇒ (⇒ B) ⇒ B): B

    Curried version of foldRight

    Curried version of foldRight

    Definition Classes
    Foldable
  44. def foldr1Opt[A](fa: F[A])(f: (A) ⇒ (⇒ A) ⇒ A): Option[A]
    Definition Classes
    Foldable
  45. 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

    Curried version of foldRightM

    Definition Classes
    Foldable
  46. final def getClass(): Class[_]
    Definition Classes
    AnyRef → Any
    Annotations
    @native()
  47. def hashCode(): Int
    Definition Classes
    AnyRef → Any
    Annotations
    @native()
  48. 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

    Definition Classes
    Foldable
  49. 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

    Definition Classes
    Foldable
  50. def intercalate[A](fa: F[A], a: A)(implicit A: Monoid[A]): A

    Insert an A between every A, yielding the sum.

    Insert an A between every A, yielding the sum.

    Definition Classes
    Foldable
  51. final def isInstanceOf[T0]: Boolean
    Definition Classes
    Any
  52. def length[A](fa: F[A]): Int

    Deforested alias for toStream(fa).size.

    Deforested alias for toStream(fa).size.

    Definition Classes
    Foldable
  53. def longDigits[A](fa: F[A])(implicit d: <:<[A, Digit]): Long
    Definition Classes
    Foldable
  54. def maximum[A](fa: F[A])(implicit arg0: Order[A]): Option[A]

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

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

    Definition Classes
    Foldable
  55. 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.

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

    Definition Classes
    Foldable
  56. 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.

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

    Definition Classes
    Foldable
  57. def minimum[A](fa: F[A])(implicit arg0: Order[A]): Option[A]

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

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

    Definition Classes
    Foldable
  58. 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.

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

    Definition Classes
    Foldable
  59. 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.

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

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

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

    Definition Classes
    Foldable
  66. 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

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

    Definition Classes
    Foldable
  67. def selectSplit[A](fa: F[A])(p: (A) ⇒ Boolean): List[NonEmptyList[A]]

    Selects groups of elements that satisfy p and discards others.

    Selects groups of elements that satisfy p and discards others.

    Definition Classes
    Foldable
  68. def sequenceF_[M[_], A](ffa: F[Free[M, A]]): Free[M, Unit]

    sequence_ for Free.

    sequence_ for Free. collapses into a single Free *

    Definition Classes
    Foldable
  69. def sequenceS_[S, A](fga: F[State[S, A]]): State[S, Unit]

    sequence_ specialized to State *

    sequence_ specialized to State *

    Definition Classes
    Foldable
  70. 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.

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

    Definition Classes
    Foldable
  71. 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
  72. 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
  73. 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.

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

    Definition Classes
    Foldable
  74. def suml1Opt[A](fa: F[A])(implicit A: Semigroup[A]): Option[A]
    Definition Classes
    FoldableParent
  75. def sumr1Opt[A](fa: F[A])(implicit A: Semigroup[A]): Option[A]
    Definition Classes
    FoldableParent
  76. final def synchronized[T0](arg0: ⇒ T0): T0
    Definition Classes
    AnyRef
  77. def to[A, G[_]](fa: F[A])(implicit c: CanBuildFrom[Nothing, A, G[A]]): G[A]
    Definition Classes
    Foldable
  78. def toEphemeralStream[A](fa: F[A]): EphemeralStream[A]
    Definition Classes
    Foldable
  79. def toIList[A](fa: F[A]): IList[A]
    Definition Classes
    Foldable
  80. def toIndexedSeq[A](fa: F[A]): IndexedSeq[A]
    Definition Classes
    Foldable
  81. def toList[A](fa: F[A]): List[A]
    Definition Classes
    Foldable
  82. def toSet[A](fa: F[A]): Set[A]
    Definition Classes
    Foldable
  83. def toStream[A](fa: F[A]): Stream[A]
    Definition Classes
    Foldable
  84. def toString(): String
    Definition Classes
    AnyRef → Any
  85. def traverseS_[S, A, B](fa: F[A])(f: (A) ⇒ State[S, B]): State[S, Unit]

    traverse_ specialized to State *

    traverse_ specialized to State *

    Definition Classes
    Foldable
  86. 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.

    A version of traverse_ that infers the type constructor M.

    Definition Classes
    Foldable
  87. 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.

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

    Definition Classes
    Foldable
  88. final def wait(): Unit
    Definition Classes
    AnyRef
    Annotations
    @throws( ... )
  89. final def wait(arg0: Long, arg1: Int): Unit
    Definition Classes
    AnyRef
    Annotations
    @throws( ... )
  90. final def wait(arg0: Long): Unit
    Definition Classes
    AnyRef
    Annotations
    @native() @throws( ... )

Deprecated Value Members

  1. def foldMapIdentity[A](fa: F[A])(implicit F: Monoid[A]): A

    Unbiased sum of monoidal values.

    Unbiased sum of monoidal values.

    Definition Classes
    Foldable
    Annotations
    @deprecated
    Deprecated

    (Since version 7.1) use fold, it has the exact same signature and implementation

Inherited from Foldable[F]

Inherited from FoldableParent[F]

Inherited from AnyRef

Inherited from Any

Ungrouped