Scalactic 3.2.17/org.scalactic.anyvals/NonEmptyList

NonEmptyList

final class NonEmptyList[+T] extends AnyVal

A non-empty list: an ordered, immutable, non-empty collection of elements with LinearSeq performance characteristics.

The purpose of NonEmptyList is to allow you to express in a type that a List is non-empty, thereby eliminating the need for (and potential exception from) a run-time check for non-emptiness. For a non-empty sequence with IndexedSeq performance, see Every.

== Constructing NonEmptyLists ==

You can construct a NonEmptyList by passing one or more elements to the NonEmptyList.apply factory method:

scala> NonEmptyList(1, 2, 3)
res0: org.scalactic.anyvals.NonEmptyList[Int] = NonEmptyList(1, 2, 3)

Alternatively you can cons elements onto the End singleton object, similar to making a List starting with Nil:

scala> 1 :: 2 :: 3 :: Nil
res0: List[Int] = List(1, 2, 3)

scala> 1 :: 2 :: 3 :: End
res1: org.scalactic.NonEmptyList[Int] = NonEmptyList(1, 2, 3)

Note that although Nil is a List[Nothing], End is not a NonEmptyList[Nothing], because no empty NonEmptyList exists. (A non-empty list is a series of connected links; if you have no links, you have no non-empty list.)

scala> val nil: List[Nothing] = Nil
nil: List[Nothing] = List()

scala> val nada: NonEmptyList[Nothing] = End
<console>:16: error: type mismatch;
found   : org.scalactic.anyvals.End.type
required: org.scalactic.anyvals.NonEmptyList[Nothing]
      val nada: NonEmptyList[Nothing] = End
                                        ^

== Working with NonEmptyLists ==

NonEmptyList does not extend Scala's Seq or Traversable traits because these require that implementations may be empty. For example, if you invoke tail on a Seq that contains just one element, you'll get an empty Seq:

scala> List(1).tail
res6: List[Int] = List()

On the other hand, many useful methods exist on Seq that when invoked on a non-empty Seq are guaranteed to not result in an empty Seq. For convenience, NonEmptyList defines a method corresponding to every such Seq method. Here are some examples:

NonEmptyList(1, 2, 3).map(_ + 1)                        // Result: NonEmptyList(2, 3, 4)
NonEmptyList(1).map(_ + 1)                              // Result: NonEmptyList(2)
NonEmptyList(1, 2, 3).containsSlice(NonEmptyList(2, 3)) // Result: true
NonEmptyList(1, 2, 3).containsSlice(NonEmptyList(3, 4)) // Result: false
NonEmptyList(-1, -2, 3, 4, 5).minBy(_.abs)              // Result: -1

NonEmptyList does not currently define any methods corresponding to Seq methods that could result in an empty Seq. However, an implicit converison from NonEmptyList to List is defined in the NonEmptyList companion object that will be applied if you attempt to call one of the missing methods. As a result, you can invoke filter on an NonEmptyList, even though filter could result in an empty sequence—but the result type will be List instead of NonEmptyList:

NonEmptyList(1, 2, 3).filter(_ < 10) // Result: List(1, 2, 3)
NonEmptyList(1, 2, 3).filter(_ > 10) // Result: List()

You can use NonEmptyLists in for expressions. The result will be an NonEmptyList unless you use a filter (an if clause). Because filters are desugared to invocations of filter, the result type will switch to a List at that point. Here are some examples:

scala> import org.scalactic.anyvals._
import org.scalactic.anyvals._

scala> for (i <- NonEmptyList(1, 2, 3)) yield i + 1
res0: org.scalactic.anyvals.NonEmptyList[Int] = NonEmptyList(2, 3, 4)

scala> for (i <- NonEmptyList(1, 2, 3) if i < 10) yield i + 1
res1: List[Int] = List(2, 3, 4)

scala> for {
    |   i <- NonEmptyList(1, 2, 3)
    |   j <- NonEmptyList('a', 'b', 'c')
    | } yield (i, j)
res3: org.scalactic.anyvals.NonEmptyList[(Int, Char)] =
       NonEmptyList((1,a), (1,b), (1,c), (2,a), (2,b), (2,c), (3,a), (3,b), (3,c))

scala> for {
    |   i <- NonEmptyList(1, 2, 3) if i < 10
    |   j <- NonEmptyList('a', 'b', 'c')
    | } yield (i, j)
res6: List[(Int, Char)] =
       List((1,a), (1,b), (1,c), (2,a), (2,b), (2,c), (3,a), (3,b), (3,c))
Type parameters:
T

the type of elements contained in this NonEmptyList

Companion:
object
Source:
NonEmptyList.scala
class AnyVal
trait Matchable
class Any

Value members

Concrete methods

def ++[U >: T](other: NonEmptyList[U]): NonEmptyList[U]

Returns a new NonEmptyList containing the elements of this NonEmptyList followed by the elements of the passed NonEmptyList. The element type of the resulting NonEmptyList is the most specific superclass encompassing the element types of this and the passed NonEmptyList.

Returns a new NonEmptyList containing the elements of this NonEmptyList followed by the elements of the passed NonEmptyList. The element type of the resulting NonEmptyList is the most specific superclass encompassing the element types of this and the passed NonEmptyList.

Type parameters:
U

the element type of the returned NonEmptyList

Value parameters:
other

the NonEmptyList to append

Returns:

a new NonEmptyList that contains all the elements of this NonEmptyList followed by all elements of other.

Source:
NonEmptyList.scala
def ++[U >: T](other: Every[U]): NonEmptyList[U]

Returns a new NonEmptyList containing the elements of this NonEmptyList followed by the elements of the passed Every. The element type of the resulting NonEmptyList is the most specific superclass encompassing the element types of this NonEmptyList and the passed Every.

Returns a new NonEmptyList containing the elements of this NonEmptyList followed by the elements of the passed Every. The element type of the resulting NonEmptyList is the most specific superclass encompassing the element types of this NonEmptyList and the passed Every.

Type parameters:
U

the element type of the returned NonEmptyList

Value parameters:
other

the Every to append

Returns:

a new NonEmptyList that contains all the elements of this NonEmptyList followed by all elements of other.

Source:
NonEmptyList.scala
def ++[U >: T](other: IterableOnce[U]): NonEmptyList[U]

Returns a new NonEmptyList containing the elements of this NonEmptyList followed by the elements of the passed GenTraversableOnce. The element type of the resulting NonEmptyList is the most specific superclass encompassing the element types of this NonEmptyList and the passed GenTraversableOnce.

Returns a new NonEmptyList containing the elements of this NonEmptyList followed by the elements of the passed GenTraversableOnce. The element type of the resulting NonEmptyList is the most specific superclass encompassing the element types of this NonEmptyList and the passed GenTraversableOnce.

Type parameters:
U

the element type of the returned NonEmptyList

Value parameters:
other

the GenTraversableOnce to append

Returns:

a new NonEmptyList that contains all the elements of this NonEmptyList followed by all elements of other.

Source:
NonEmptyList.scala
final def +:[U >: T](element: U): NonEmptyList[U]

Returns a new NonEmptyList with the given element prepended.

Returns a new NonEmptyList with the given element prepended.

Note that :-ending operators are right associative. A mnemonic for +: vs. :+ is: the COLon goes on the COLlection side.

Value parameters:
element

the element to prepend to this NonEmptyList

Returns:

a new NonEmptyList consisting of element followed by all elements of this NonEmptyList.

Source:
NonEmptyList.scala
def :+[U >: T](element: U): NonEmptyList[U]

Returns a new NonEmptyList with the given element appended.

Returns a new NonEmptyList with the given element appended.

Note a mnemonic for +: vs. :+ is: the COLon goes on the COLlection side.

Value parameters:
element

the element to append to this NonEmptyList

Returns:

a new NonEmptyList consisting of all elements of this NonEmptyList followed by element.

Source:
NonEmptyList.scala
final def ::[U >: T](element: U): NonEmptyList[U]

Adds an element to the beginning of this NonEmptyList.

Adds an element to the beginning of this NonEmptyList.

Note that :-ending operators are right associative. A mnemonic for +: vs. :+ is: the COLon goes on the COLlection side.

Value parameters:
element

the element to prepend to this NonEmptyList

Returns:

a NonEmptyList that contains element as first element and that continues with this NonEmptyList.

Source:
NonEmptyList.scala
def :::[U >: T](other: NonEmptyList[U]): NonEmptyList[U]

Returns a new NonEmptyList containing the elements of this NonEmptyList followed by the elements of the passed NonEmptyList. The element type of the resulting NonEmptyList is the most specific superclass encompassing the element types of this and the passed NonEmptyList.

Returns a new NonEmptyList containing the elements of this NonEmptyList followed by the elements of the passed NonEmptyList. The element type of the resulting NonEmptyList is the most specific superclass encompassing the element types of this and the passed NonEmptyList.

Type parameters:
U

the element type of the returned NonEmptyList

Value parameters:
other

the NonEmptyList to append

Returns:

a new NonEmptyList that contains all the elements of this NonEmptyList followed by all elements of other.

Source:
NonEmptyList.scala
def :::[U >: T](other: Every[U]): NonEmptyList[U]

Returns a new NonEmptyList containing the elements of this NonEmptyList followed by the elements of the passed Every. The element type of the resulting NonEmptyList is the most specific superclass encompassing the element types of this and the passed Every.

Returns a new NonEmptyList containing the elements of this NonEmptyList followed by the elements of the passed Every. The element type of the resulting NonEmptyList is the most specific superclass encompassing the element types of this and the passed Every.

Type parameters:
U

the element type of the returned NonEmptyList

Value parameters:
other

the Every to append

Returns:

a new NonEmptyList that contains all the elements of this NonEmptyList followed by all elements of other.

Source:
NonEmptyList.scala
def :::[U >: T](other: IterableOnce[U]): NonEmptyList[U]

Returns a new NonEmptyList containing the elements of this NonEmptyList followed by the elements of the passed GenTraversableOnce. The element type of the resulting NonEmptyList is the most specific superclass encompassing the element types of this NonEmptyList and the passed GenTraversableOnce.

Returns a new NonEmptyList containing the elements of this NonEmptyList followed by the elements of the passed GenTraversableOnce. The element type of the resulting NonEmptyList is the most specific superclass encompassing the element types of this NonEmptyList and the passed GenTraversableOnce.

Type parameters:
U

the element type of the returned NonEmptyList

Value parameters:
other

the GenTraversableOnce to append

Returns:

a new NonEmptyList that contains all the elements of this NonEmptyList followed by all elements of other.

Source:
NonEmptyList.scala
final def addString(sb: StringBuilder): StringBuilder

Appends all elements of this NonEmptyList to a string builder. The written text will consist of a concatenation of the result of invoking toString on of every element of this NonEmptyList, without any separator string.

Appends all elements of this NonEmptyList to a string builder. The written text will consist of a concatenation of the result of invoking toString on of every element of this NonEmptyList, without any separator string.

Value parameters:
sb

the string builder to which elements will be appended

Returns:

the string builder, sb, to which elements were appended.

Source:
NonEmptyList.scala
final def addString(sb: StringBuilder, sep: String): StringBuilder

Appends all elements of this NonEmptyList to a string builder using a separator string. The written text will consist of a concatenation of the result of invoking toString on of every element of this NonEmptyList, separated by the string sep.

Appends all elements of this NonEmptyList to a string builder using a separator string. The written text will consist of a concatenation of the result of invoking toString on of every element of this NonEmptyList, separated by the string sep.

Value parameters:
sb

the string builder to which elements will be appended

sep

the separator string

Returns:

the string builder, sb, to which elements were appended.

Source:
NonEmptyList.scala
final def addString(sb: StringBuilder, start: String, sep: String, end: String): StringBuilder

Appends all elements of this NonEmptyList to a string builder using start, end, and separator strings. The written text will consist of a concatenation of the string start; the result of invoking toString on all elements of this NonEmptyList, separated by the string sep; and the string end

Appends all elements of this NonEmptyList to a string builder using start, end, and separator strings. The written text will consist of a concatenation of the string start; the result of invoking toString on all elements of this NonEmptyList, separated by the string sep; and the string end

Value parameters:
sb

the string builder to which elements will be appended

sep

the separator string

start

the ending string

Returns:

the string builder, sb, to which elements were appended.

Source:
NonEmptyList.scala
final def apply(idx: Int): T

Selects an element by its index in the NonEmptyList.

Selects an element by its index in the NonEmptyList.

Returns:

the element of this NonEmptyList at index idx, where 0 indicates the first element.

Source:
NonEmptyList.scala
final def collectFirst[U](pf: PartialFunction[T, U]): Option[U]

Finds the first element of this NonEmptyList for which the given partial function is defined, if any, and applies the partial function to it.

Finds the first element of this NonEmptyList for which the given partial function is defined, if any, and applies the partial function to it.

Value parameters:
pf

the partial function

Returns:

an Option containing pf applied to the first element for which it is defined, or None if the partial function was not defined for any element.

Source:
NonEmptyList.scala
final def contains(elem: Any): Boolean

Indicates whether this NonEmptyList contains a given value as an element.

Indicates whether this NonEmptyList contains a given value as an element.

Value parameters:
elem

the element to look for

Returns:

true if this NonEmptyList has an element that is equal (as determined by ==) to elem, false otherwise.

Source:
NonEmptyList.scala
final def containsSlice[B](that: Seq[B]): Boolean

Indicates whether this NonEmptyList contains a given GenSeq as a slice.

Indicates whether this NonEmptyList contains a given GenSeq as a slice.

Value parameters:
that

the GenSeq slice to look for

Returns:

true if this NonEmptyList contains a slice with the same elements as that, otherwise false.

Source:
NonEmptyList.scala
final def containsSlice[B](that: Every[B]): Boolean

Indicates whether this NonEmptyList contains a given Every as a slice.

Indicates whether this NonEmptyList contains a given Every as a slice.

Value parameters:
that

the Every slice to look for

Returns:

true if this NonEmptyList contains a slice with the same elements as that, otherwise false.

Source:
NonEmptyList.scala
final def containsSlice[B](that: NonEmptyList[B]): Boolean

Indicates whether this NonEmptyList contains a given NonEmptyList as a slice.

Indicates whether this NonEmptyList contains a given NonEmptyList as a slice.

Value parameters:
that

the NonEmptyList slice to look for

Returns:

true if this NonEmptyList contains a slice with the same elements as that, otherwise false.

Source:
NonEmptyList.scala
final def copyToArray[U >: T](arr: Array[U]): Unit

Copies values of this NonEmptyList to an array. Fills the given array arr with values of this NonEmptyList. Copying will stop once either the end of the current NonEmptyList is reached, or the end of the array is reached.

Copies values of this NonEmptyList to an array. Fills the given array arr with values of this NonEmptyList. Copying will stop once either the end of the current NonEmptyList is reached, or the end of the array is reached.

Value parameters:
arr

the array to fill

Source:
NonEmptyList.scala
final def copyToArray[U >: T](arr: Array[U], start: Int): Unit

Copies values of this NonEmptyList to an array. Fills the given array arr with values of this NonEmptyList, beginning at index start. Copying will stop once either the end of the current NonEmptyList is reached, or the end of the array is reached.

Copies values of this NonEmptyList to an array. Fills the given array arr with values of this NonEmptyList, beginning at index start. Copying will stop once either the end of the current NonEmptyList is reached, or the end of the array is reached.

Value parameters:
arr

the array to fill

start

the starting index

Source:
NonEmptyList.scala
final def copyToArray[U >: T](arr: Array[U], start: Int, len: Int): Unit

Copies values of this NonEmptyList to an array. Fills the given array arr with at most len elements of this NonEmptyList, beginning at index start. Copying will stop once either the end of the current NonEmptyList is reached, the end of the array is reached, or len elements have been copied.

Copies values of this NonEmptyList to an array. Fills the given array arr with at most len elements of this NonEmptyList, beginning at index start. Copying will stop once either the end of the current NonEmptyList is reached, the end of the array is reached, or len elements have been copied.

Value parameters:
arr

the array to fill

len

the maximum number of elements to copy

start

the starting index

Source:
NonEmptyList.scala
final def copyToBuffer[U >: T](buf: Buffer[U]): Unit

Copies all elements of this NonEmptyList to a buffer.

Copies all elements of this NonEmptyList to a buffer.

Value parameters:
buf

the buffer to which elements are copied

Source:
NonEmptyList.scala
final def corresponds[B](that: Seq[B])(p: (T, B) => Boolean): Boolean

Indicates whether every element of this NonEmptyList relates to the corresponding element of a given GenSeq by satisfying a given predicate.

Indicates whether every element of this NonEmptyList relates to the corresponding element of a given GenSeq by satisfying a given predicate.

Type parameters:
B

the type of the elements of that

Value parameters:
p

the predicate, which relates elements from this NonEmptyList and the passed GenSeq

that

the GenSeq to compare for correspondence

Returns:

true if this NonEmptyList and the passed GenSeq have the same length and p(x, y) is true for all corresponding elements x of this NonEmptyList and y of that, otherwise false.

Source:
NonEmptyList.scala
final def corresponds[B](that: Every[B])(p: (T, B) => Boolean): Boolean

Indicates whether every element of this NonEmptyList relates to the corresponding element of a given Every by satisfying a given predicate.

Indicates whether every element of this NonEmptyList relates to the corresponding element of a given Every by satisfying a given predicate.

Type parameters:
B

the type of the elements of that

Value parameters:
p

the predicate, which relates elements from this NonEmptyList and the passed Every

that

the Every to compare for correspondence

Returns:

true if this NonEmptyList and the passed Every have the same length and p(x, y) is true for all corresponding elements x of this NonEmptyList and y of that, otherwise false.

Source:
NonEmptyList.scala
final def corresponds[B](that: NonEmptyList[B])(p: (T, B) => Boolean): Boolean

Indicates whether every element of this NonEmptyList relates to the corresponding element of a given NonEmptyList by satisfying a given predicate.

Indicates whether every element of this NonEmptyList relates to the corresponding element of a given NonEmptyList by satisfying a given predicate.

Type parameters:
B

the type of the elements of that

Value parameters:
p

the predicate, which relates elements from this and the passed NonEmptyList

that

the NonEmptyList to compare for correspondence

Returns:

true if this and the passed NonEmptyList have the same length and p(x, y) is true for all corresponding elements x of this NonEmptyList and y of that, otherwise false.

Source:
NonEmptyList.scala
final def count(p: T => Boolean): Int

Counts the number of elements in this NonEmptyList that satisfy a predicate.

Counts the number of elements in this NonEmptyList that satisfy a predicate.

Value parameters:
p

the predicate used to test elements.

Returns:

the number of elements satisfying the predicate p.

Source:
NonEmptyList.scala
final def distinct: NonEmptyList[T]

Builds a new NonEmptyList from this NonEmptyList without any duplicate elements.

Builds a new NonEmptyList from this NonEmptyList without any duplicate elements.

Returns:

A new NonEmptyList that contains the first occurrence of every element of this NonEmptyList.

Source:
NonEmptyList.scala
final def endsWith[B](that: Seq[B]): Boolean

Indicates whether this NonEmptyList ends with the given GenSeq.

Indicates whether this NonEmptyList ends with the given GenSeq.

Value parameters:
that

the sequence to test

Returns:

true if this NonEmptyList has that as a suffix, false otherwise.

Source:
NonEmptyList.scala
final def endsWith[B](that: Every[B]): Boolean

Indicates whether this NonEmptyList ends with the given Every.

Indicates whether this NonEmptyList ends with the given Every.

Value parameters:
that

the Every to test

Returns:

true if this NonEmptyList has that as a suffix, false otherwise.

Source:
NonEmptyList.scala
final def endsWith[B](that: NonEmptyList[B]): Boolean

Indicates whether this NonEmptyList ends with the given NonEmptyList.

Indicates whether this NonEmptyList ends with the given NonEmptyList.

Value parameters:
that

the NonEmptyList to test

Returns:

true if this NonEmptyList has that as a suffix, false otherwise.

Source:
NonEmptyList.scala
final def exists(p: T => Boolean): Boolean

Indicates whether a predicate holds for at least one of the elements of this NonEmptyList.

Indicates whether a predicate holds for at least one of the elements of this NonEmptyList.

Value parameters:
the

predicate used to test elements.

Returns:

true if the given predicate p holds for some of the elements of this NonEmptyList, otherwise false.

Source:
NonEmptyList.scala
final def find(p: T => Boolean): Option[T]

Finds the first element of this NonEmptyList that satisfies the given predicate, if any.

Finds the first element of this NonEmptyList that satisfies the given predicate, if any.

Value parameters:
p

the predicate used to test elements

Returns:

an Some containing the first element in this NonEmptyList that satisfies p, or None if none exists.

Source:
NonEmptyList.scala
final def flatMap[U](f: T => NonEmptyList[U]): NonEmptyList[U]

Builds a new NonEmptyList by applying a function to all elements of this NonEmptyList and using the elements of the resulting NonEmptyLists.

Builds a new NonEmptyList by applying a function to all elements of this NonEmptyList and using the elements of the resulting NonEmptyLists.

Type parameters:
U

the element type of the returned NonEmptyList

Value parameters:
f

the function to apply to each element.

Returns:

a new NonEmptyList containing elements obtained by applying the given function f to each element of this NonEmptyList and concatenating the elements of resulting NonEmptyLists.

Source:
NonEmptyList.scala
final def flatten[B](implicit ev: T <:< NonEmptyList[B]): NonEmptyList[B]

Converts this NonEmptyList of NonEmptyLists into a NonEmptyList formed by the elements of the nested NonEmptyLists.

Converts this NonEmptyList of NonEmptyLists into a NonEmptyList formed by the elements of the nested NonEmptyLists.

Note: You cannot use this flatten method on a NonEmptyList that contains a GenTraversableOnces, because if all the nested GenTraversableOnces were empty, you'd end up with an empty NonEmptyList.

Returns:

a new NonEmptyList resulting from concatenating all nested NonEmptyLists.

Source:
NonEmptyList.scala
final def fold[U >: T](z: U)(op: (U, U) => U): U

Folds the elements of this NonEmptyList using the specified associative binary operator.

Folds the elements of this NonEmptyList using the specified associative binary operator.

The order in which operations are performed on elements is unspecified and may be nondeterministic.

Type parameters:
U

a type parameter for the binary operator, a supertype of T.

Value parameters:
op

a binary operator that must be associative

z

a neutral element for the fold operation; may be added to the result an arbitrary number of times, and must not change the result (e.g., Nil for list concatenation, 0 for addition, or 1 for multiplication.)

Returns:

the result of applying fold operator op between all the elements and z

Source:
NonEmptyList.scala
final def foldLeft[B](z: B)(op: (B, T) => B): B

Applies a binary operator to a start value and all elements of this NonEmptyList, going left to right.

Applies a binary operator to a start value and all elements of this NonEmptyList, going left to right.

Type parameters:
B

the result type of the binary operator.

Value parameters:
op

the binary operator.

z

the start value.

Returns:

the result of inserting op between consecutive elements of this NonEmptyList, going left to right, with the start value, z, on the left:

op(...op(op(z, x_1), x_2), ..., x_n)

where x1, ..., xn are the elements of this NonEmptyList.

Source:
NonEmptyList.scala
final def foldRight[B](z: B)(op: (T, B) => B): B

Applies a binary operator to all elements of this NonEmptyList and a start value, going right to left.

Applies a binary operator to all elements of this NonEmptyList and a start value, going right to left.

Type parameters:
B

the result of the binary operator

Value parameters:
op

the binary operator

z

the start value

Returns:

the result of inserting op between consecutive elements of this NonEmptyList, going right to left, with the start value, z, on the right:

op(x_1, op(x_2, ... op(x_n, z)...))

where x1, ..., xn are the elements of this NonEmptyList.

Source:
NonEmptyList.scala
final def forall(p: T => Boolean): Boolean

Indicates whether a predicate holds for all elements of this NonEmptyList.

Indicates whether a predicate holds for all elements of this NonEmptyList.

Value parameters:
p

the predicate used to test elements.

Returns:

true if the given predicate p holds for all elements of this NonEmptyList, otherwise false.

Source:
NonEmptyList.scala
final def foreach(f: T => Unit): Unit

Applies a function f to all elements of this NonEmptyList.

Applies a function f to all elements of this NonEmptyList.

Value parameters:
f

the function that is applied for its side-effect to every element. The result of function f is discarded.

Source:
NonEmptyList.scala
final def groupBy[K](f: T => K): Map[K, NonEmptyList[T]]

Partitions this NonEmptyList into a map of NonEmptyLists according to some discriminator function.

Partitions this NonEmptyList into a map of NonEmptyLists according to some discriminator function.

Type parameters:
K

the type of keys returned by the discriminator function.

Value parameters:
f

the discriminator function.

Returns:

A map from keys to NonEmptyLists such that the following invariant holds:

(nonEmptyList.toList partition f)(k) = xs filter (x => f(x) == k)

That is, every key k is bound to a NonEmptyList of those elements x for which f(x) equals k.

Source:
NonEmptyList.scala
final def grouped(size: Int): Iterator[NonEmptyList[T]]

Partitions elements into fixed size NonEmptyLists.

Partitions elements into fixed size NonEmptyLists.

Value parameters:
size

the number of elements per group

Returns:

An iterator producing NonEmptyLists of size size, except the last will be truncated if the elements don't divide evenly.

Source:
NonEmptyList.scala
final def hasDefiniteSize: Boolean

Returns true to indicate this NonEmptyList has a definite size, since all NonEmptyLists are strict collections.

Returns true to indicate this NonEmptyList has a definite size, since all NonEmptyLists are strict collections.

Source:
NonEmptyList.scala
final def head: T

Selects the first element of this NonEmptyList.

Selects the first element of this NonEmptyList.

Returns:

the first element of this NonEmptyList.

Source:
NonEmptyList.scala
final def headOption: Option[T]

Selects the first element of this NonEmptyList and returns it wrapped in a Some.

Selects the first element of this NonEmptyList and returns it wrapped in a Some.

Returns:

the first element of this NonEmptyList, wrapped in a Some.

Source:
NonEmptyList.scala
final def indexOf[U >: T](elem: U): Int

Finds index of first occurrence of some value in this NonEmptyList.

Finds index of first occurrence of some value in this NonEmptyList.

Value parameters:
elem

the element value to search for.

Returns:

the index of the first element of this NonEmptyList that is equal (as determined by ==) to elem, or -1, if none exists.

Source:
NonEmptyList.scala
final def indexOf[U >: T](elem: U, from: Int): Int

Finds index of first occurrence of some value in this NonEmptyList after or at some start index.

Finds index of first occurrence of some value in this NonEmptyList after or at some start index.

Value parameters:
elem

the element value to search for.

from

the start index

Returns:

the index >= from of the first element of this NonEmptyList that is equal (as determined by ==) to elem, or -1, if none exists.

Source:
NonEmptyList.scala
final def indexOfSlice[U >: T](that: Seq[U]): Int

Finds first index where this NonEmptyList contains a given GenSeq as a slice.

Finds first index where this NonEmptyList contains a given GenSeq as a slice.

Value parameters:
that

the GenSeq defining the slice to look for

Returns:

the first index at which the elements of this NonEmptyList starting at that index match the elements of GenSeq that, or -1 of no such subsequence exists.

Source:
NonEmptyList.scala
final def indexOfSlice[U >: T](that: Seq[U], from: Int): Int

Finds first index after or at a start index where this NonEmptyList contains a given GenSeq as a slice.

Finds first index after or at a start index where this NonEmptyList contains a given GenSeq as a slice.

Value parameters:
from

the start index

that

the GenSeq defining the slice to look for

Returns:

the first index >= from at which the elements of this NonEmptyList starting at that index match the elements of GenSeq that, or -1 of no such subsequence exists.

Source:
NonEmptyList.scala
final def indexOfSlice[U >: T](that: Every[U]): Int

Finds first index where this NonEmptyList contains a given Every as a slice.

Finds first index where this NonEmptyList contains a given Every as a slice.

Value parameters:
that

the Every defining the slice to look for

Returns:

the first index such that the elements of this NonEmptyList starting at this index match the elements of Every that, or -1 of no such subsequence exists.

Source:
NonEmptyList.scala
final def indexOfSlice[U >: T](that: NonEmptyList[U]): Int

Finds first index where this NonEmptyList contains a given NonEmptyList as a slice.

Finds first index where this NonEmptyList contains a given NonEmptyList as a slice.

Value parameters:
that

the NonEmptyList defining the slice to look for

Returns:

the first index such that the elements of this NonEmptyList starting at this index match the elements of NonEmptyList that, or -1 of no such subsequence exists.

Source:
NonEmptyList.scala
final def indexOfSlice[U >: T](that: Every[U], from: Int): Int

Finds first index after or at a start index where this NonEmptyList contains a given Every as a slice.

Finds first index after or at a start index where this NonEmptyList contains a given Every as a slice.

Value parameters:
from

the start index

that

the Every defining the slice to look for

Returns:

the first index >= from such that the elements of this NonEmptyList starting at this index match the elements of Every that, or -1 of no such subsequence exists.

Source:
NonEmptyList.scala
final def indexOfSlice[U >: T](that: NonEmptyList[U], from: Int): Int

Finds first index after or at a start index where this NonEmptyList contains a given NonEmptyList as a slice.

Finds first index after or at a start index where this NonEmptyList contains a given NonEmptyList as a slice.

Value parameters:
from

the start index

that

the NonEmptyList defining the slice to look for

Returns:

the first index >= from such that the elements of this NonEmptyList starting at this index match the elements of NonEmptyList that, or -1 of no such subsequence exists.

Source:
NonEmptyList.scala
final def indexWhere(p: T => Boolean): Int

Finds index of the first element satisfying some predicate.

Finds index of the first element satisfying some predicate.

Value parameters:
p

the predicate used to test elements.

Returns:

the index of the first element of this NonEmptyList that satisfies the predicate p, or -1, if none exists.

Source:
NonEmptyList.scala
final def indexWhere(p: T => Boolean, from: Int): Int

Finds index of the first element satisfying some predicate after or at some start index.

Finds index of the first element satisfying some predicate after or at some start index.

Value parameters:
from

the start index

p

the predicate used to test elements.

Returns:

the index >= from of the first element of this NonEmptyList that satisfies the predicate p, or -1, if none exists.

Source:
NonEmptyList.scala
final def indices: Range

Produces the range of all indices of this NonEmptyList.

Produces the range of all indices of this NonEmptyList.

Returns:

a Range value from 0 to one less than the length of this NonEmptyList.

Source:
NonEmptyList.scala
final def isDefinedAt(idx: Int): Boolean

Tests whether this NonEmptyList contains given index.

Tests whether this NonEmptyList contains given index.

Value parameters:
idx

the index to test

Returns:

true if this NonEmptyList contains an element at position idx, false otherwise.

Source:
NonEmptyList.scala
final def isEmpty: Boolean

Returns false to indicate this NonEmptyList, like all NonEmptyLists, is non-empty.

Returns false to indicate this NonEmptyList, like all NonEmptyLists, is non-empty.

Returns:

false

Source:
NonEmptyList.scala
final def isTraversableAgain: Boolean

Returns true to indicate this NonEmptyList, like all NonEmptyLists, can be traversed repeatedly.

Returns true to indicate this NonEmptyList, like all NonEmptyLists, can be traversed repeatedly.

Returns:

true

Source:
NonEmptyList.scala
final def iterator: Iterator[T]

Creates and returns a new iterator over all elements contained in this NonEmptyList.

Creates and returns a new iterator over all elements contained in this NonEmptyList.

Returns:

the new iterator

Source:
NonEmptyList.scala
final def last: T

Selects the last element of this NonEmptyList.

Selects the last element of this NonEmptyList.

Returns:

the last element of this NonEmptyList.

Source:
NonEmptyList.scala
final def lastIndexOf[U >: T](elem: U): Int

Finds the index of the last occurrence of some value in this NonEmptyList.

Finds the index of the last occurrence of some value in this NonEmptyList.

Value parameters:
elem

the element value to search for.

Returns:

the index of the last element of this NonEmptyList that is equal (as determined by ==) to elem, or -1, if none exists.

Source:
NonEmptyList.scala
final def lastIndexOf[U >: T](elem: U, end: Int): Int

Finds the index of the last occurrence of some value in this NonEmptyList before or at a given end index.

Finds the index of the last occurrence of some value in this NonEmptyList before or at a given end index.

Value parameters:
elem

the element value to search for.

end

the end index.

Returns:

the index >= end of the last element of this NonEmptyList that is equal (as determined by ==) to elem, or -1, if none exists.

Source:
NonEmptyList.scala
final def lastIndexOfSlice[U >: T](that: Seq[U]): Int

Finds the last index where this NonEmptyList contains a given GenSeq as a slice.

Finds the last index where this NonEmptyList contains a given GenSeq as a slice.

Value parameters:
that

the GenSeq defining the slice to look for

Returns:

the last index at which the elements of this NonEmptyList starting at that index match the elements of GenSeq that, or -1 of no such subsequence exists.

Source:
NonEmptyList.scala
final def lastIndexOfSlice[U >: T](that: Seq[U], end: Int): Int

Finds the last index before or at a given end index where this NonEmptyList contains a given GenSeq as a slice.

Finds the last index before or at a given end index where this NonEmptyList contains a given GenSeq as a slice.

Value parameters:
end

the end index

that

the GenSeq defining the slice to look for

Returns:

the last index >= end at which the elements of this NonEmptyList starting at that index match the elements of GenSeq that, or -1 of no such subsequence exists.

Source:
NonEmptyList.scala
final def lastIndexOfSlice[U >: T](that: Every[U]): Int

Finds the last index where this NonEmptyList contains a given Every as a slice.

Finds the last index where this NonEmptyList contains a given Every as a slice.

Value parameters:
that

the Every defining the slice to look for

Returns:

the last index at which the elements of this NonEmptyList starting at that index match the elements of Every that, or -1 of no such subsequence exists.

Source:
NonEmptyList.scala
final def lastIndexOfSlice[U >: T](that: NonEmptyList[U]): Int

Finds the last index where this NonEmptyList contains a given NonEmptyList as a slice.

Finds the last index where this NonEmptyList contains a given NonEmptyList as a slice.

Value parameters:
that

the NonEmptyList defining the slice to look for

Returns:

the last index at which the elements of this NonEmptyList starting at that index match the elements of NonEmptyList that, or -1 of no such subsequence exists.

Source:
NonEmptyList.scala
final def lastIndexOfSlice[U >: T](that: Every[U], end: Int): Int

Finds the last index before or at a given end index where this NonEmptyList contains a given Every as a slice.

Finds the last index before or at a given end index where this NonEmptyList contains a given Every as a slice.

Value parameters:
end

the end index

that

the Every defining the slice to look for

Returns:

the last index >= end at which the elements of this NonEmptyList starting at that index match the elements of Every that, or -1 of no such subsequence exists.

Source:
NonEmptyList.scala
final def lastIndexOfSlice[U >: T](that: NonEmptyList[U], end: Int): Int

Finds the last index before or at a given end index where this NonEmptyList contains a given NonEmptyList as a slice.

Finds the last index before or at a given end index where this NonEmptyList contains a given NonEmptyList as a slice.

Value parameters:
end

the end index

that

the NonEmptyList defining the slice to look for

Returns:

the last index >= end at which the elements of this NonEmptyList starting at that index match the elements of NonEmptyList that, or -1 of no such subsequence exists.

Source:
NonEmptyList.scala
final def lastIndexWhere(p: T => Boolean): Int

Finds index of last element satisfying some predicate.

Finds index of last element satisfying some predicate.

Value parameters:
p

the predicate used to test elements.

Returns:

the index of the last element of this NonEmptyList that satisfies the predicate p, or -1, if none exists.

Source:
NonEmptyList.scala
final def lastIndexWhere(p: T => Boolean, end: Int): Int

Finds index of last element satisfying some predicate before or at given end index.

Finds index of last element satisfying some predicate before or at given end index.

Value parameters:
end

the end index

p

the predicate used to test elements.

Returns:

the index >= end of the last element of this NonEmptyList that satisfies the predicate p, or -1, if none exists.

Source:
NonEmptyList.scala
final def lastOption: Option[T]

Returns the last element of this NonEmptyList, wrapped in a Some.

Returns the last element of this NonEmptyList, wrapped in a Some.

Returns:

the last element, wrapped in a Some.

Source:
NonEmptyList.scala
final def length: Int

The length of this NonEmptyList.

The length of this NonEmptyList.

Note: length and size yield the same result, which will be >= 1.

Returns:

the number of elements in this NonEmptyList.

Source:
NonEmptyList.scala
final def lengthCompare(len: Int): Int

Compares the length of this NonEmptyList to a test value.

Compares the length of this NonEmptyList to a test value.

Value parameters:
len

the test value that gets compared with the length.

Returns:

a value x where

x < 0 if this.length < len
x == 0 if this.length == len
x > 0 if this.length > len
Source:
NonEmptyList.scala
final def map[U](f: T => U): NonEmptyList[U]

Builds a new NonEmptyList by applying a function to all elements of this NonEmptyList.

Builds a new NonEmptyList by applying a function to all elements of this NonEmptyList.

Type parameters:
U

the element type of the returned NonEmptyList.

Value parameters:
f

the function to apply to each element.

Returns:

a new NonEmptyList resulting from applying the given function f to each element of this NonEmptyList and collecting the results.

Source:
NonEmptyList.scala
final def max[U >: T](implicit cmp: Ordering[U]): T

Finds the largest element.

Finds the largest element.

Returns:

the largest element of this NonEmptyList.

Source:
NonEmptyList.scala
final def maxBy[U](f: T => U)(implicit cmp: Ordering[U]): T

Finds the largest result after applying the given function to every element.

Finds the largest result after applying the given function to every element.

Returns:

the largest result of applying the given function to every element of this NonEmptyList.

Source:
NonEmptyList.scala
final def min[U >: T](implicit cmp: Ordering[U]): T

Finds the smallest element.

Finds the smallest element.

Returns:

the smallest element of this NonEmptyList.

Source:
NonEmptyList.scala
final def minBy[U](f: T => U)(implicit cmp: Ordering[U]): T

Finds the smallest result after applying the given function to every element.

Finds the smallest result after applying the given function to every element.

Returns:

the smallest result of applying the given function to every element of this NonEmptyList.

Source:
NonEmptyList.scala
final def mkString: String

Displays all elements of this NonEmptyList in a string.

Displays all elements of this NonEmptyList in a string.

Returns:

a string representation of this NonEmptyList. In the resulting string, the result of invoking toString on all elements of this NonEmptyList follow each other without any separator string.

Source:
NonEmptyList.scala
final def mkString(sep: String): String

Displays all elements of this NonEmptyList in a string using a separator string.

Displays all elements of this NonEmptyList in a string using a separator string.

Value parameters:
sep

the separator string

Returns:

a string representation of this NonEmptyList. In the resulting string, the result of invoking toString on all elements of this NonEmptyList are separated by the string sep.

Source:
NonEmptyList.scala
final def mkString(start: String, sep: String, end: String): String

Displays all elements of this NonEmptyList in a string using start, end, and separator strings.

Displays all elements of this NonEmptyList in a string using start, end, and separator strings.

Value parameters:
end

the ending string.

sep

the separator string.

start

the starting string.

Returns:

a string representation of this NonEmptyList. The resulting string begins with the string start and ends with the string end. Inside, In the resulting string, the result of invoking toString on all elements of this NonEmptyList are separated by the string sep.

Source:
NonEmptyList.scala
final def nonEmpty: Boolean

Returns true to indicate this NonEmptyList, like all NonEmptyLists, is non-empty.

Returns true to indicate this NonEmptyList, like all NonEmptyLists, is non-empty.

Returns:

true

Source:
NonEmptyList.scala
final def padTo[U >: T](len: Int, elem: U): NonEmptyList[U]

A copy of this NonEmptyList with an element value appended until a given target length is reached.

A copy of this NonEmptyList with an element value appended until a given target length is reached.

Value parameters:
elem

he padding value

len

the target length

Returns:

a new NonEmptyList consisting of all elements of this NonEmptyList followed by the minimal number of occurrences of elem so that the resulting NonEmptyList has a length of at least len.

Source:
NonEmptyList.scala
final def patch[U >: T](from: Int, that: NonEmptyList[U], replaced: Int): NonEmptyList[U]

Produces a new NonEmptyList where a slice of elements in this NonEmptyList is replaced by another NonEmptyList

Produces a new NonEmptyList where a slice of elements in this NonEmptyList is replaced by another NonEmptyList

Value parameters:
from

the index of the first replaced element

replaced

the number of elements to drop in the original NonEmptyList

that

the NonEmptyList whose elements should replace a slice in this NonEmptyList

Source:
NonEmptyList.scala
final def permutations: Iterator[NonEmptyList[T]]

Iterates over distinct permutations.

Iterates over distinct permutations.

Here's an example:

NonEmptyList('a', 'b', 'b').permutations.toList = List(NonEmptyList(a, b, b), NonEmptyList(b, a, b), NonEmptyList(b, b, a))
Returns:

an iterator that traverses the distinct permutations of this NonEmptyList.

Source:
NonEmptyList.scala
final def prefixLength(p: T => Boolean): Int

Returns the length of the longest prefix whose elements all satisfy some predicate.

Returns the length of the longest prefix whose elements all satisfy some predicate.

Value parameters:
p

the predicate used to test elements.

Returns:

the length of the longest prefix of this NonEmptyList such that every element of the segment satisfies the predicate p.

Source:
NonEmptyList.scala
final def product[U >: T](implicit num: Numeric[U]): U

The result of multiplying all the elements of this NonEmptyList.

The result of multiplying all the elements of this NonEmptyList.

This method can be invoked for any NonEmptyList[T] for which an implicit Numeric[T] exists.

Returns:

the product of all elements

Source:
NonEmptyList.scala
final def reduce[U >: T](op: (U, U) => U): U

Reduces the elements of this NonEmptyList using the specified associative binary operator.

Reduces the elements of this NonEmptyList using the specified associative binary operator.

The order in which operations are performed on elements is unspecified and may be nondeterministic.

Type parameters:
U

a type parameter for the binary operator, a supertype of T.

Value parameters:
op

a binary operator that must be associative.

Returns:

the result of applying reduce operator op between all the elements of this NonEmptyList.

Source:
NonEmptyList.scala
final def reduceLeft[U >: T](op: (U, T) => U): U

Applies a binary operator to all elements of this NonEmptyList, going left to right.

Applies a binary operator to all elements of this NonEmptyList, going left to right.

Type parameters:
U

the result type of the binary operator.

Value parameters:
op

the binary operator.

Returns:

the result of inserting op between consecutive elements of this NonEmptyList, going left to right:

op(...op(op(x_1, x_2), x_3), ..., x_n)

where x1, ..., xn are the elements of this NonEmptyList.

Source:
NonEmptyList.scala
final def reduceLeftOption[U >: T](op: (U, T) => U): Option[U]

Applies a binary operator to all elements of this NonEmptyList, going left to right, returning the result in a Some.

Applies a binary operator to all elements of this NonEmptyList, going left to right, returning the result in a Some.

Type parameters:
U

the result type of the binary operator.

Value parameters:
op

the binary operator.

Returns:

a Some containing the result of reduceLeft(op)

Source:
NonEmptyList.scala
final def reduceOption[U >: T](op: (U, U) => U): Option[U]
final def reduceRight[U >: T](op: (T, U) => U): U

Applies a binary operator to all elements of this NonEmptyList, going right to left.

Applies a binary operator to all elements of this NonEmptyList, going right to left.

Type parameters:
U

the result of the binary operator

Value parameters:
op

the binary operator

Returns:

the result of inserting op between consecutive elements of this NonEmptyList, going right to left:

op(x_1, op(x_2, ... op(x_{n-1}, x_n)...))

where x1, ..., xn are the elements of this NonEmptyList.

Source:
NonEmptyList.scala
final def reduceRightOption[U >: T](op: (T, U) => U): Option[U]

Applies a binary operator to all elements of this NonEmptyList, going right to left, returning the result in a Some.

Applies a binary operator to all elements of this NonEmptyList, going right to left, returning the result in a Some.

Type parameters:
U

the result of the binary operator

Value parameters:
op

the binary operator

Returns:

a Some containing the result of reduceRight(op)

Source:
NonEmptyList.scala
final def reverse: NonEmptyList[T]

Returns new NonEmptyList with elements in reverse order.

Returns new NonEmptyList with elements in reverse order.

Returns:

a new NonEmptyList with all elements of this NonEmptyList in reversed order.

Source:
NonEmptyList.scala
final def reverseIterator: Iterator[T]

An iterator yielding elements in reverse order.

An iterator yielding elements in reverse order.

Note: nonEmptyList.reverseIterator is the same as nonEmptyList.reverse.iterator, but might be more efficient.

Returns:

an iterator yielding the elements of this NonEmptyList in reversed order

Source:
NonEmptyList.scala
final def reverseMap[U](f: T => U): NonEmptyList[U]

Builds a new NonEmptyList by applying a function to all elements of this NonEmptyList and collecting the results in reverse order.

Builds a new NonEmptyList by applying a function to all elements of this NonEmptyList and collecting the results in reverse order.

Note: nonEmptyList.reverseMap(f) is the same as nonEmptyList.reverse.map(f), but might be more efficient.

Type parameters:
U

the element type of the returned NonEmptyList.

Value parameters:
f

the function to apply to each element.

Returns:

a new NonEmptyList resulting from applying the given function f to each element of this NonEmptyList and collecting the results in reverse order.

Source:
NonEmptyList.scala
final def sameElements[U >: T](that: Iterable[U]): Boolean

Checks if the given GenIterable contains the same elements in the same order as this NonEmptyList.

Checks if the given GenIterable contains the same elements in the same order as this NonEmptyList.

Value parameters:
that

the GenIterable with which to compare

Returns:

true, if both this NonEmptyList and the given GenIterable contain the same elements in the same order, false otherwise.

Source:
NonEmptyList.scala
final def sameElements[U >: T](that: Every[U]): Boolean

Checks if the given Every contains the same elements in the same order as this NonEmptyList.

Checks if the given Every contains the same elements in the same order as this NonEmptyList.

Value parameters:
that

the Every with which to compare

Returns:

true, if both this and the given Every contain the same elements in the same order, false otherwise.

Source:
NonEmptyList.scala
final def sameElements[U >: T](that: NonEmptyList[U]): Boolean

Checks if the given NonEmptyList contains the same elements in the same order as this NonEmptyList.

Checks if the given NonEmptyList contains the same elements in the same order as this NonEmptyList.

Value parameters:
that

the NonEmptyList with which to compare

Returns:

true, if both this and the given NonEmptyList contain the same elements in the same order, false otherwise.

Source:
NonEmptyList.scala
final def scan[U >: T](z: U)(op: (U, U) => U): NonEmptyList[U]

Computes a prefix scan of the elements of this NonEmptyList.

Computes a prefix scan of the elements of this NonEmptyList.

Note: The neutral element z may be applied more than once.

Here are some examples:

NonEmptyList(1, 2, 3).scan(0)(_ + _) == NonEmptyList(0, 1, 3, 6)
NonEmptyList(1, 2, 3).scan("z")(_ + _.toString) == NonEmptyList("z", "z1", "z12", "z123")
Type parameters:
U

a type parameter for the binary operator, a supertype of T, and the type of the resulting NonEmptyList.

Value parameters:
op

a binary operator that must be associative

z

a neutral element for the scan operation; may be added to the result an arbitrary number of times, and must not change the result (e.g., Nil for list concatenation, 0 for addition, or 1 for multiplication.)

Returns:

a new NonEmptyList containing the prefix scan of the elements in this NonEmptyList

Source:
NonEmptyList.scala
final def scanLeft[B](z: B)(op: (B, T) => B): NonEmptyList[B]

Produces a NonEmptyList containing cumulative results of applying the operator going left to right.

Produces a NonEmptyList containing cumulative results of applying the operator going left to right.

Here are some examples:

NonEmptyList(1, 2, 3).scanLeft(0)(_ + _) == NonEmptyList(0, 1, 3, 6)
NonEmptyList(1, 2, 3).scanLeft("z")(_ + _) == NonEmptyList("z", "z1", "z12", "z123")
Type parameters:
B

the result type of the binary operator and type of the resulting NonEmptyList

Value parameters:
op

the binary operator.

z

the start value.

Returns:

a new NonEmptyList containing the intermediate results of inserting op between consecutive elements of this NonEmptyList, going left to right, with the start value, z, on the left.

Source:
NonEmptyList.scala
final def scanRight[B](z: B)(op: (T, B) => B): NonEmptyList[B]

Produces a NonEmptyList containing cumulative results of applying the operator going right to left.

Produces a NonEmptyList containing cumulative results of applying the operator going right to left.

Here are some examples:

NonEmptyList(1, 2, 3).scanRight(0)(_ + _) == NonEmptyList(6, 5, 3, 0)
NonEmptyList(1, 2, 3).scanRight("z")(_ + _) == NonEmptyList("123z", "23z", "3z", "z")
Type parameters:
B

the result of the binary operator and type of the resulting NonEmptyList

Value parameters:
op

the binary operator

z

the start value

Returns:

a new NonEmptyList containing the intermediate results of inserting op between consecutive elements of this NonEmptyList, going right to left, with the start value, z, on the right.

Source:
NonEmptyList.scala
final def segmentLength(p: T => Boolean, from: Int): Int

Computes length of longest segment whose elements all satisfy some predicate.

Computes length of longest segment whose elements all satisfy some predicate.

Value parameters:
from

the index where the search starts.

p

the predicate used to test elements.

the

length of the longest segment of this NonEmptyList starting from index from such that every element of the segment satisfies the predicate p.

Source:
NonEmptyList.scala
final def size: Int

The size of this NonEmptyList.

The size of this NonEmptyList.

Note: length and size yield the same result, which will be >= 1.

Returns:

the number of elements in this NonEmptyList.

Source:
NonEmptyList.scala
final def sliding(size: Int): Iterator[NonEmptyList[T]]

Groups elements in fixed size blocks by passing a “sliding window” over them (as opposed to partitioning them, as is done in grouped.)

Groups elements in fixed size blocks by passing a “sliding window” over them (as opposed to partitioning them, as is done in grouped.)

Value parameters:
size

the number of elements per group

Returns:

an iterator producing NonEmptyLists of size size, except the last and the only element will be truncated if there are fewer elements than size.

Source:
NonEmptyList.scala
final def sliding(size: Int, step: Int): Iterator[NonEmptyList[T]]

Groups elements in fixed size blocks by passing a “sliding window” over them (as opposed to partitioning them, as is done in grouped.), moving the sliding window by a given step each time.

Groups elements in fixed size blocks by passing a “sliding window” over them (as opposed to partitioning them, as is done in grouped.), moving the sliding window by a given step each time.

Value parameters:
size

the number of elements per group

step

the distance between the first elements of successive groups

Returns:

an iterator producing NonEmptyLists of size size, except the last and the only element will be truncated if there are fewer elements than size.

Source:
NonEmptyList.scala
final def sortBy[U](f: T => U)(implicit ord: Ordering[U]): NonEmptyList[T]

Sorts this NonEmptyList according to the Ordering of the result of applying the given function to every element.

Sorts this NonEmptyList according to the Ordering of the result of applying the given function to every element.

Type parameters:
U

the target type of the transformation f, and the type where the Ordering ord is defined.

Value parameters:
f

the transformation function mapping elements to some other domain U.

ord

the ordering assumed on domain U.

Returns:

a NonEmptyList consisting of the elements of this NonEmptyList sorted according to the Ordering where x < y if ord.lt(f(x), f(y)).

Source:
NonEmptyList.scala
final def sortWith(lt: (T, T) => Boolean): NonEmptyList[T]

Sorts this NonEmptyList according to a comparison function.

Sorts this NonEmptyList according to a comparison function.

The sort is stable. That is, elements that are equal (as determined by lt) appear in the same order in the sorted NonEmptyList as in the original.

Value parameters:
the

comparison function that tests whether its first argument precedes its second argument in the desired ordering.

Returns:

a NonEmptyList consisting of the elements of this NonEmptyList sorted according to the comparison function lt.

Source:
NonEmptyList.scala
final def sorted[U >: T](implicit ord: Ordering[U]): NonEmptyList[U]

Sorts this NonEmptyList according to an Ordering.

Sorts this NonEmptyList according to an Ordering.

The sort is stable. That is, elements that are equal (as determined by lt) appear in the same order in the sorted NonEmptyList as in the original.

Value parameters:
ord

the Ordering to be used to compare elements.

the

comparison function that tests whether its first argument precedes its second argument in the desired ordering.

Returns:

a NonEmptyList consisting of the elements of this NonEmptyList sorted according to the comparison function lt.

Source:
NonEmptyList.scala
final def startsWith[B](that: Seq[B]): Boolean

Indicates whether this NonEmptyList starts with the given GenSeq.

Indicates whether this NonEmptyList starts with the given GenSeq.

Value parameters:
that

the GenSeq slice to look for in this NonEmptyList

Returns:

true if this NonEmptyList has that as a prefix, false otherwise.

Source:
NonEmptyList.scala
final def startsWith[B](that: Seq[B], offset: Int): Boolean

Indicates whether this NonEmptyList starts with the given GenSeq at the given index.

Indicates whether this NonEmptyList starts with the given GenSeq at the given index.

Value parameters:
offset

the index at which this NonEmptyList is searched.

that

the GenSeq slice to look for in this NonEmptyList

Returns:

true if this NonEmptyList has that as a slice at the index offset, false otherwise.

Source:
NonEmptyList.scala
final def startsWith[B](that: Every[B]): Boolean

Indicates whether this NonEmptyList starts with the given Every.

Indicates whether this NonEmptyList starts with the given Every.

Value parameters:
that

the Every to test

Returns:

true if this collection has that as a prefix, false otherwise.

Source:
NonEmptyList.scala
final def startsWith[B](that: NonEmptyList[B]): Boolean

Indicates whether this NonEmptyList starts with the given NonEmptyList.

Indicates whether this NonEmptyList starts with the given NonEmptyList.

Value parameters:
that

the NonEmptyList to test

Returns:

true if this collection has that as a prefix, false otherwise.

Source:
NonEmptyList.scala
final def startsWith[B](that: Every[B], offset: Int): Boolean

Indicates whether this NonEmptyList starts with the given Every at the given index.

Indicates whether this NonEmptyList starts with the given Every at the given index.

Value parameters:
offset

the index at which this NonEmptyList is searched.

that

the Every slice to look for in this NonEmptyList

Returns:

true if this NonEmptyList has that as a slice at the index offset, false otherwise.

Source:
NonEmptyList.scala
final def startsWith[B](that: NonEmptyList[B], offset: Int): Boolean

Indicates whether this NonEmptyList starts with the given NonEmptyList at the given index.

Indicates whether this NonEmptyList starts with the given NonEmptyList at the given index.

Value parameters:
offset

the index at which this NonEmptyList is searched.

that

the NonEmptyList slice to look for in this NonEmptyList

Returns:

true if this NonEmptyList has that as a slice at the index offset, false otherwise.

Source:
NonEmptyList.scala
def stringPrefix: String

Returns "NonEmptyList", the prefix of this object's toString representation.

Returns "NonEmptyList", the prefix of this object's toString representation.

Returns:

the string "NonEmptyList"

Source:
NonEmptyList.scala
final def sum[U >: T](implicit num: Numeric[U]): U

The result of summing all the elements of this NonEmptyList.

The result of summing all the elements of this NonEmptyList.

This method can be invoked for any NonEmptyList[T] for which an implicit Numeric[T] exists.

Returns:

the sum of all elements

Source:
NonEmptyList.scala
final def to[Col[_]](factory: Factory[T, Col[T]]): Col[T]

Converts this NonEmptyList into a collection of type Col by copying all elements.

Converts this NonEmptyList into a collection of type Col by copying all elements.

Type parameters:
Col

the collection type to build.

Returns:

a new collection containing all elements of this NonEmptyList.

Source:
NonEmptyList.scala
final def toArray[U >: T](implicit classTag: ClassTag[U]): Array[U]

Converts this NonEmptyList to an array.

Converts this NonEmptyList to an array.

Returns:

an array containing all elements of this NonEmptyList. A ClassTag must be available for the element type of this NonEmptyList.

Source:
NonEmptyList.scala
final def toBuffer[U >: T]: Buffer[U]

Converts this NonEmptyList to a mutable buffer.

Converts this NonEmptyList to a mutable buffer.

Returns:

a buffer containing all elements of this NonEmptyList.

Source:
NonEmptyList.scala
final def toIndexedSeq: IndexedSeq[T]

Converts this NonEmptyList to an immutable IndexedSeq.

Converts this NonEmptyList to an immutable IndexedSeq.

Returns:

an immutable IndexedSeq containing all elements of this NonEmptyList.

Source:
NonEmptyList.scala
final def toIterable: Iterable[T]

Converts this NonEmptyList to an iterable collection.

Converts this NonEmptyList to an iterable collection.

Returns:

an Iterable containing all elements of this NonEmptyList.

Source:
NonEmptyList.scala
final def toIterator: Iterator[T]

Returns an Iterator over the elements in this NonEmptyList.

Returns an Iterator over the elements in this NonEmptyList.

Returns:

an Iterator containing all elements of this NonEmptyList.

Source:
NonEmptyList.scala
final def toMap[K, V](implicit ev: T <:< (K, V)): Map[K, V]

Converts this NonEmptyList to a map.

Converts this NonEmptyList to a map.

This method is unavailable unless the elements are members of Tuple2, each ((K, V)) becoming a key-value pair in the map. Duplicate keys will be overwritten by later keys.

Returns:

a map of type immutable.Map[K, V] containing all key/value pairs of type (K, V) of this NonEmptyList.

Source:
NonEmptyList.scala
final def toSeq: Seq[T]

Converts this NonEmptyList to an immutable IndexedSeq.

Converts this NonEmptyList to an immutable IndexedSeq.

Returns:

an immutable IndexedSeq containing all elements of this NonEmptyList.

Source:
NonEmptyList.scala
final def toSet[U >: T]: Set[U]

Converts this NonEmptyList to a set.

Converts this NonEmptyList to a set.

Returns:

a set containing all elements of this NonEmptyList.

Source:
NonEmptyList.scala
final def toStream: Stream[T]

Converts this NonEmptyList to a stream.

Converts this NonEmptyList to a stream.

Returns:

a stream containing all elements of this NonEmptyList.

Source:
NonEmptyList.scala
override def toString: String

Returns a string representation of this NonEmptyList.

Returns a string representation of this NonEmptyList.

Returns:

the string "NonEmptyList" followed by the result of invoking toString on this NonEmptyList's elements, surrounded by parentheses.

Definition Classes
Any
Source:
NonEmptyList.scala
final def toVector: Vector[T]

Converts this NonEmptyList to a Vector.

Converts this NonEmptyList to a Vector.

Returns:

a Vector containing all elements of this NonEmptyList.

Source:
NonEmptyList.scala
final def transpose[U](implicit ev: T <:< NonEmptyList[U]): NonEmptyList[NonEmptyList[U]]
final def union[U >: T](that: Every[U]): NonEmptyList[U]

Produces a new NonEmptyList that contains all elements of this NonEmptyList and also all elements of a given Every.

Produces a new NonEmptyList that contains all elements of this NonEmptyList and also all elements of a given Every.

nonEmptyListX union everyY is equivalent to nonEmptyListX ++ everyY.

Another way to express this is that nonEmptyListX union everyY computes the order-presevring multi-set union of nonEmptyListX and everyY. This union method is hence a counter-part of diff and intersect that also work on multi-sets.

Value parameters:
that

the Every to add.

Returns:

a new NonEmptyList that contains all elements of this NonEmptyList followed by all elements of that Every.

Source:
NonEmptyList.scala
final def union[U >: T](that: NonEmptyList[U]): NonEmptyList[U]

Produces a new NonEmptyList that contains all elements of this NonEmptyList and also all elements of a given NonEmptyList.

Produces a new NonEmptyList that contains all elements of this NonEmptyList and also all elements of a given NonEmptyList.

nonEmptyListX union nonEmptyListY is equivalent to nonEmptyListX ++ nonEmptyListY.

Another way to express this is that nonEmptyListX union nonEmptyListY computes the order-presevring multi-set union of nonEmptyListX and nonEmptyListY. This union method is hence a counter-part of diff and intersect that also work on multi-sets.

Value parameters:
that

the NonEmptyList to add.

Returns:

a new NonEmptyList that contains all elements of this NonEmptyList followed by all elements of that.

Source:
NonEmptyList.scala
final def union[U >: T](that: Seq[U]): NonEmptyList[U]

Produces a new NonEmptyList that contains all elements of this NonEmptyList and also all elements of a given GenSeq.

Produces a new NonEmptyList that contains all elements of this NonEmptyList and also all elements of a given GenSeq.

nonEmptyListX union ys is equivalent to nonEmptyListX ++ ys.

Another way to express this is that nonEmptyListX union ys computes the order-presevring multi-set union of nonEmptyListX and ys. This union method is hence a counter-part of diff and intersect that also work on multi-sets.

Value parameters:
that

the GenSeq to add.

Returns:

a new NonEmptyList that contains all elements of this NonEmptyList followed by all elements of that GenSeq.

Source:
NonEmptyList.scala
final def unzip[L, R](implicit asPair: T => (L, R)): (NonEmptyList[L], NonEmptyList[R])

Converts this NonEmptyList of pairs into two NonEmptyLists of the first and second half of each pair.

Converts this NonEmptyList of pairs into two NonEmptyLists of the first and second half of each pair.

Type parameters:
L

the type of the first half of the element pairs

R

the type of the second half of the element pairs

Value parameters:
asPair

an implicit conversion that asserts that the element type of this NonEmptyList is a pair.

Returns:

a pair of NonEmptyLists, containing the first and second half, respectively, of each element pair of this NonEmptyList.

Source:
NonEmptyList.scala
final def unzip3[L, M, R](implicit asTriple: T => (L, M, R)): (NonEmptyList[L], NonEmptyList[M], NonEmptyList[R])

Converts this NonEmptyList of triples into three NonEmptyLists of the first, second, and and third element of each triple.

Converts this NonEmptyList of triples into three NonEmptyLists of the first, second, and and third element of each triple.

Type parameters:
L

the type of the first member of the element triples

R

the type of the third member of the element triples

Value parameters:
asTriple

an implicit conversion that asserts that the element type of this NonEmptyList is a triple.

Returns:

a triple of NonEmptyLists, containing the first, second, and third member, respectively, of each element triple of this NonEmptyList.

Source:
NonEmptyList.scala
final def updated[U >: T](idx: Int, elem: U): NonEmptyList[U]

A copy of this NonEmptyList with one single replaced element.

A copy of this NonEmptyList with one single replaced element.

Value parameters:
elem

the replacing element

idx

the position of the replacement

Returns:

a copy of this NonEmptyList with the element at position idx replaced by elem.

Throws:
IndexOutOfBoundsException

if the passed index is greater than or equal to the length of this NonEmptyList

Source:
NonEmptyList.scala
final def zipAll[O, U >: T](other: Iterable[O], thisElem: U, otherElem: O): NonEmptyList[(U, O)]

Returns a NonEmptyList formed from this NonEmptyList and an iterable collection by combining corresponding elements in pairs. If one of the two collections is shorter than the other, placeholder elements will be used to extend the shorter collection to the length of the longer.

Returns a NonEmptyList formed from this NonEmptyList and an iterable collection by combining corresponding elements in pairs. If one of the two collections is shorter than the other, placeholder elements will be used to extend the shorter collection to the length of the longer.

Value parameters:
other

the Iterable providing the second half of each result pair

thatElem

the element to be used to fill up the result if that Iterable is shorter than this NonEmptyList.

thisElem

the element to be used to fill up the result if this NonEmptyList is shorter than that Iterable.

Returns:

a new NonEmptyList containing pairs consisting of corresponding elements of this NonEmptyList and that. The length of the returned collection is the maximum of the lengths of this NonEmptyList and that. If this NonEmptyList is shorter than that, thisElem values are used to pad the result. If that is shorter than this NonEmptyList, thatElem values are used to pad the result.

Source:
NonEmptyList.scala
final def zipWithIndex: NonEmptyList[(T, Int)]

Zips this NonEmptyList with its indices.

Zips this NonEmptyList with its indices.

Returns:

A new NonEmptyList containing pairs consisting of all elements of this NonEmptyList paired with their index. Indices start at 0.

Source:
NonEmptyList.scala

Deprecated methods

@deprecated("The /: method has been deprecated and will be removed in a future version of Scalactic. Please use foldLeft instead.", "3.1.x")
final def /:[B](z: B)(op: (B, T) => B): B

The /: method has been deprecated and will be removed in a future version of Scalactic. Please use foldLeft instead.

The /: method has been deprecated and will be removed in a future version of Scalactic. Please use foldLeft instead.

This method has been deprecated for consistency with Scala 2.13's collections API.

Fold left: applies a binary operator to a start value, z, and all elements of this NonEmptyList, going left to right.

Note: /: is alternate syntax for the foldLeft method; z /: non-empty list is the same as non-empty list foldLeft z.

Type parameters:
B

the result of the binary operator

Value parameters:
op

the binary operator

z

the start value

Returns:

the result of inserting op between consecutive elements of this NonEmptyList, going left to right, with the start value, z, on the left:

op(...op(op(z, x_1), x_2), ..., x_n)

where x1, ..., xn are the elements of this NonEmptyList.

Deprecated
Source:
NonEmptyList.scala
@deprecated("The :\\ method has been deprecated and will be removed in a future version of Scalactic. Please use foldRight instead.", "3.1.x")
final def :\[B](z: B)(op: (T, B) => B): B

The :\ method has been deprecated and will be removed in a future version of Scalactic. Please use foldRight instead.

The :\ method has been deprecated and will be removed in a future version of Scalactic. Please use foldRight instead.

This method has been deprecated for consistency with Scala 2.13's collections API.

Fold right: applies a binary operator to all elements of this NonEmptyList and a start value, going right to left.

Note: :</code> is alternate syntax for the foldRight method; non-empty list :</code> z is the same as non-empty list foldRight z.

Type parameters:
B

the result of the binary operator

Value parameters:
op

the binary operator

z

the start value

Returns:

the result of inserting op between consecutive elements of this NonEmptyList, going right to left, with the start value, z, on the right:

op(x_1, op(x_2, ... op(x_n, z)...))

where x1, ..., xn are the elements of this NonEmptyList.

Deprecated
Source:
NonEmptyList.scala

Concrete fields

val toList: List[T]