scalaz

# Foldable

#### trait Foldable[F[_]] extends AnyRef

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

Self Type
Foldable[F]
Source
Foldable.scala
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### 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: AnyRef): Boolean

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2. #### final def !=(arg0: Any): Boolean

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3. #### final def ##(): Int

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4. #### final def ==(arg0: AnyRef): Boolean

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5. #### final def ==(arg0: Any): Boolean

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6. #### def all[A](fa: F[A])(p: (A) ⇒ Boolean): Boolean

Whether all `A`s in `fa` yield true from `p`.

7. #### def allM[G[_], A](fa: F[A])(p: (A) ⇒ G[Boolean])(implicit G: Monad[G]): G[Boolean]

`all` with monadic traversal.

8. #### def any[A](fa: F[A])(p: (A) ⇒ Boolean): Boolean

Whether any `A`s in `fa` yield true from `p`.

9. #### def anyM[G[_], A](fa: F[A])(p: (A) ⇒ G[Boolean])(implicit G: Monad[G]): G[Boolean]

`any` with monadic traversal.

10. #### final def asInstanceOf[T0]: T0

Definition Classes
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11. #### def clone(): AnyRef

Attributes
protected[java.lang]
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@throws( ... )

19. #### 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

20. #### def count[A](fa: F[A]): Int

Deforested alias for `toStream(fa).size`.

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

Whether `a` is an element of `fa`.

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

Deforested alias for `toStream(fa).isEmpty`.

23. #### final def eq(arg0: AnyRef): Boolean

Definition Classes
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24. #### def equals(arg0: Any): Boolean

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25. #### def finalize(): Unit

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protected[java.lang]
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26. #### def fold[M](t: F[M])(implicit arg0: Monoid[M]): M

Combine the elements of a structure using a monoid.

27. #### def foldLeft[A, B](fa: F[A], z: B)(f: (B, A) ⇒ B): B

Left-associative fold of a structure.

28. #### 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.

29. #### def foldMapIdentity[A, B](fa: F[A])(implicit F: Monoid[A]): A

Unbiased sum of monoidal values.

30. #### 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.

32. #### final def foldl[A, B](fa: F[A], z: B)(f: (B) ⇒ (A) ⇒ B): B

Curred version of `foldLeft`

33. #### 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`

34. #### final def foldr[A, B](fa: F[A], z: ⇒ B)(f: (A) ⇒ (⇒ B) ⇒ B): B

Curried version of `foldRight`

35. #### 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`

36. #### final def getClass(): Class[_]

Definition Classes
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37. #### def hashCode(): Int

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

Insert an `A` between every A, yielding the sum.

39. #### final def isInstanceOf[T0]: Boolean

Definition Classes
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41. #### def maximum[A](fa: F[A])(implicit arg0: Order[A]): Option[A]

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

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

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

43. #### final def ne(arg0: AnyRef): Boolean

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44. #### final def notify(): Unit

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45. #### final def notifyAll(): Unit

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46. #### 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

47. #### def selectSplit[A](fa: F[A])(p: (A) ⇒ Boolean): List[List[A]]

Selects groups of elements that satisfy p and discards others.

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

`sequence_` specialized to `State` *

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

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

50. #### def splitWith[A](fa: F[A])(p: (A) ⇒ Boolean): List[List[A]]

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

51. #### final def synchronized[T0](arg0: ⇒ T0): T0

Definition Classes
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56. #### def toString(): String

Definition Classes
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57. #### def traverseS_[S, A, B](fa: F[A])(f: (A) ⇒ State[S, B]): State[S, Unit]

`traverse_` specialized to `State` *

58. #### 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`.

59. #### final def wait(): Unit

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60. #### final def wait(arg0: Long, arg1: Int): Unit

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61. #### final def wait(arg0: Long): Unit

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