final case class NonEmptyList[+A](head: A, tail: List[A]) extends Product with Serializable

A data type which represents a non empty list of A, with single element (head) and optional structure (tail).

Source
NonEmptyList.scala
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Inherited
  1. NonEmptyList
  2. Serializable
  3. Serializable
  4. Product
  5. Equals
  6. AnyRef
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Visibility
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Instance Constructors

  1. new NonEmptyList(head: A, tail: List[A])

Value Members

  1. final def !=(arg0: Any): Boolean
    Definition Classes
    AnyRef → Any
  2. final def ##(): Int
    Definition Classes
    AnyRef → Any
  3. def ++[AA >: A](l: List[AA]): NonEmptyList[AA]
  4. def ::[AA >: A](a: AA): NonEmptyList[AA]
  5. def :::[AA >: A](other: NonEmptyList[AA]): NonEmptyList[AA]

    Alias for concatNel

    Alias for concatNel

    scala> import cats.data.NonEmptyList
    scala> val nel = NonEmptyList.of(1, 2, 3)
    scala> nel ::: NonEmptyList.of(4, 5)
    res0: cats.data.NonEmptyList[Int] = NonEmptyList(1, 2, 3, 4, 5)
  6. final def ==(arg0: Any): Boolean
    Definition Classes
    AnyRef → Any
  7. def ===[AA >: A](o: NonEmptyList[AA])(implicit AA: Eq[AA]): Boolean
  8. final def asInstanceOf[T0]: T0
    Definition Classes
    Any
  9. def clone(): AnyRef
    Attributes
    protected[java.lang]
    Definition Classes
    AnyRef
    Annotations
    @native() @throws( ... )
  10. def coflatMap[B](f: (NonEmptyList[A]) ⇒ B): NonEmptyList[B]
  11. def collect[B](pf: PartialFunction[A, B]): List[B]

    Builds a new List by applying a partial function to all the elements from this NonEmptyList on which the function is defined

    Builds a new List by applying a partial function to all the elements from this NonEmptyList on which the function is defined

    scala> import cats.data.NonEmptyList
    scala> val nel = NonEmptyList.of(1, 2, 3, 4, 5)
    scala> nel.collect { case v if v < 3 => v }
    res0: scala.collection.immutable.List[Int] = List(1, 2)
    scala> nel.collect {
         |  case v if v % 2 == 0 => "even"
         |  case _ => "odd"
         | }
    res1: scala.collection.immutable.List[String] = List(odd, even, odd, even, odd)
  12. def concat[AA >: A](other: List[AA]): NonEmptyList[AA]
  13. def concatNel[AA >: A](other: NonEmptyList[AA]): NonEmptyList[AA]

    Append another NonEmptyList

  14. def distinct[AA >: A](implicit O: Order[AA]): NonEmptyList[AA]

    Remove duplicates.

    Remove duplicates. Duplicates are checked using Order[_] instance.

  15. final def eq(arg0: AnyRef): Boolean
    Definition Classes
    AnyRef
  16. def exists(p: (A) ⇒ Boolean): Boolean

    Check whether at least one element satisfies the predicate

  17. def filter(p: (A) ⇒ Boolean): List[A]

    Remove elements not matching the predicate

    Remove elements not matching the predicate

    scala> import cats.data.NonEmptyList
    scala> val nel = NonEmptyList.of(1, 2, 3, 4, 5)
    scala> nel.filter(_ < 3)
    res0: scala.collection.immutable.List[Int] = List(1, 2)
  18. def filterNot(p: (A) ⇒ Boolean): List[A]

    Remove elements matching the predicate

    Remove elements matching the predicate

    scala> import cats.data.NonEmptyList
    scala> val nel = NonEmptyList.of(1, 2, 3, 4, 5)
    scala> nel.filterNot(_ < 3)
    res0: scala.collection.immutable.List[Int] = List(3, 4, 5)
  19. def finalize(): Unit
    Attributes
    protected[java.lang]
    Definition Classes
    AnyRef
    Annotations
    @throws( classOf[java.lang.Throwable] )
  20. def find(p: (A) ⇒ Boolean): Option[A]

    Find the first element matching the predicate, if one exists

  21. def flatMap[B](f: (A) ⇒ NonEmptyList[B]): NonEmptyList[B]
  22. def foldLeft[B](b: B)(f: (B, A) ⇒ B): B

    Left-associative fold on the structure using f.

  23. def foldRight[B](lb: Eval[B])(f: (A, Eval[B]) ⇒ Eval[B]): Eval[B]

    Right-associative fold on the structure using f.

  24. def forall(p: (A) ⇒ Boolean): Boolean

    Check whether all elements satisfy the predicate

  25. final def getClass(): Class[_]
    Definition Classes
    AnyRef → Any
    Annotations
    @native()
  26. def groupBy[B](f: (A) ⇒ B)(implicit B: Order[B]): SortedMap[B, NonEmptyList[A]]

    Groups elements inside this NonEmptyList according to the Order of the keys produced by the given mapping function.

    Groups elements inside this NonEmptyList according to the Order of the keys produced by the given mapping function.

    scala> import scala.collection.immutable.SortedMap
    scala> import cats.data.NonEmptyList
    scala> import cats.instances.boolean._
    scala> val nel = NonEmptyList.of(12, -2, 3, -5)
    scala> nel.groupBy(_ >= 0)
    res0: SortedMap[Boolean, cats.data.NonEmptyList[Int]] = Map(false -> NonEmptyList(-2, -5), true -> NonEmptyList(12, 3))
  27. def groupByNem[B](f: (A) ⇒ B)(implicit B: Order[B]): NonEmptyMap[B, NonEmptyList[A]]

    Groups elements inside this NonEmptyList according to the Order of the keys produced by the given mapping function.

    Groups elements inside this NonEmptyList according to the Order of the keys produced by the given mapping function.

    scala> import cats.data._
    scala> import cats.instances.boolean._
    scala> val nel = NonEmptyList.of(12, -2, 3, -5)
    scala> nel.groupByNem(_ >= 0)
    res0: NonEmptyMap[Boolean, NonEmptyList[Int]] = Map(false -> NonEmptyList(-2, -5), true -> NonEmptyList(12, 3))
  28. val head: A
  29. def init: List[A]

    Selects all elements except the last

    Selects all elements except the last

    scala> import cats.data.NonEmptyList
    scala> val nel = NonEmptyList.of(1, 2, 3, 4, 5)
    scala> nel.init
    res0: scala.collection.immutable.List[Int] = List(1, 2, 3, 4)
  30. final def isInstanceOf[T0]: Boolean
    Definition Classes
    Any
  31. def last: A

    Selects the last element

    Selects the last element

    scala> import cats.data.NonEmptyList
    scala> val nel = NonEmptyList.of(1, 2, 3, 4, 5)
    scala> nel.last
    res0: Int = 5
  32. def length: Int
  33. def map[B](f: (A) ⇒ B): NonEmptyList[B]

    Applies f to all the elements of the structure

  34. final def ne(arg0: AnyRef): Boolean
    Definition Classes
    AnyRef
  35. final def notify(): Unit
    Definition Classes
    AnyRef
    Annotations
    @native()
  36. final def notifyAll(): Unit
    Definition Classes
    AnyRef
    Annotations
    @native()
  37. def prepend[AA >: A](a: AA): NonEmptyList[AA]
  38. def reduce[AA >: A](implicit S: Semigroup[AA]): AA

    Reduce using the Semigroup of AA.

  39. def reduceLeft[AA >: A](f: (AA, AA) ⇒ AA): AA

    Left-associative reduce using f.

  40. def reverse: NonEmptyList[A]

    Reverse this NonEmptyList.

    Reverse this NonEmptyList.

    scala> import cats.data.NonEmptyList
    scala> val nel = NonEmptyList.of(1, 2, 3)
    scala> nel.reverse
    res0: cats.data.NonEmptyList[Int] = NonEmptyList(3, 2, 1)
  41. def show[AA >: A](implicit AA: Show[AA]): String
  42. def size: Int

    The size of this NonEmptyList

    The size of this NonEmptyList

    scala> import cats.data.NonEmptyList
    scala> val nel = NonEmptyList.of(1, 2, 3, 4, 5)
    scala> nel.size
    res0: Int = 5
  43. def sortBy[B](f: (A) ⇒ B)(implicit B: Order[B]): NonEmptyList[A]

    Sorts this NonEmptyList according to an Order on transformed B from A

    Sorts this NonEmptyList according to an Order on transformed B from A

    scala> import cats.data.NonEmptyList
    scala> import cats.instances.int._
    scala> val nel = NonEmptyList.of(('a', 4), ('z', 1), ('e', 22))
    scala> nel.sortBy(_._2)
    res0: cats.data.NonEmptyList[(Char, Int)] = NonEmptyList((z,1), (a,4), (e,22))
  44. def sorted[AA >: A](implicit AA: Order[AA]): NonEmptyList[AA]

    Sorts this NonEmptyList according to an Order

    Sorts this NonEmptyList according to an Order

    scala> import cats.data.NonEmptyList
    scala> import cats.instances.int._
    scala> val nel = NonEmptyList.of(12, 4, 3, 9)
    scala> nel.sorted
    res0: cats.data.NonEmptyList[Int] = NonEmptyList(3, 4, 9, 12)
  45. final def synchronized[T0](arg0: ⇒ T0): T0
    Definition Classes
    AnyRef
  46. val tail: List[A]
  47. def toList: List[A]

    Return the head and tail into a single list

    Return the head and tail into a single list

    scala> import cats.data.NonEmptyList
    scala> val nel = NonEmptyList.of(1, 2, 3, 4, 5)
    scala> nel.toList
    res0: scala.collection.immutable.List[Int] = List(1, 2, 3, 4, 5)
  48. def toString(): String
    Definition Classes
    NonEmptyList → AnyRef → Any
  49. def traverse[G[_], B](f: (A) ⇒ G[B])(implicit G: Applicative[G]): G[NonEmptyList[B]]
  50. final def wait(): Unit
    Definition Classes
    AnyRef
    Annotations
    @throws( ... )
  51. final def wait(arg0: Long, arg1: Int): Unit
    Definition Classes
    AnyRef
    Annotations
    @throws( ... )
  52. final def wait(arg0: Long): Unit
    Definition Classes
    AnyRef
    Annotations
    @native() @throws( ... )
  53. def zipWith[B, C](b: NonEmptyList[B])(f: (A, B) ⇒ C): NonEmptyList[C]

    Zips this NonEmptyList with another NonEmptyList and applies a function for each pair of elements.

    Zips this NonEmptyList with another NonEmptyList and applies a function for each pair of elements.

    scala> import cats.data.NonEmptyList
    scala> val as = NonEmptyList.of(1, 2, 3)
    scala> val bs = NonEmptyList.of("A", "B", "C")
    scala> as.zipWith(bs)(_ + _)
    res0: cats.data.NonEmptyList[String] = NonEmptyList(1A, 2B, 3C)
  54. def zipWithIndex: NonEmptyList[(A, Int)]

    Zips each element of this NonEmptyList with its index.

    Zips each element of this NonEmptyList with its index.

    scala> import cats.data.NonEmptyList
    scala> val nel = NonEmptyList.of("a", "b", "c")
    scala> nel.zipWithIndex
    res0: cats.data.NonEmptyList[(String, Int)] = NonEmptyList((a,0), (b,1), (c,2))

Deprecated Value Members

  1. def concat[AA >: A](other: NonEmptyList[AA]): NonEmptyList[AA]
    Annotations
    @deprecated
    Deprecated

    (Since version 1.0.0-RC1) Use concatNel

Inherited from Serializable

Inherited from Serializable

Inherited from Product

Inherited from Equals

Inherited from AnyRef

Inherited from Any

Ungrouped