Packages

t

scala.collection

GenSeqLike

trait GenSeqLike[+A, +Repr] extends GenIterableLike[A, Repr] with Equals with Parallelizable[A, ParSeq[A]]

A template trait for all sequences which may be traversed in parallel.

Source
GenSeqLike.scala
Linear Supertypes
Known Subclasses
AbstractSeq, GenSeq, IndexedSeq, IndexedSeqLike, IndexedSeqOptimized, LinearSeq, LinearSeqLike, LinearSeqOptimized, Seq, SeqLike, SeqView, SeqViewLike, Appended, DroppedWhile, EmptyView, Filtered, FlatMapped, Forced, Mapped, Patched, Prepended, Reversed, Sliced, TakenWhile, Transformed, Zipped, ZippedAll, ::, IndexedSeq, Impl, LinearSeq, List, Nil, NumericRange, Exclusive, Inclusive, Queue, Range, Inclusive, Seq, Stream, Cons, Empty, StreamView, StreamViewLike, Appended, DroppedWhile, EmptyView, Filtered, FlatMapped, Forced, Mapped, Patched, Prepended, Reversed, Sliced, TakenWhile, Transformed, Zipped, ZippedAll, StringLike, StringOps, Vector, WrappedString, AbstractBuffer, AbstractSeq, ArrayBuffer, ArrayLike, ArrayOps, ofBoolean, ofByte, ofChar, ofDouble, ofFloat, ofInt, ofLong, ofRef, ofShort, ofUnit, ArraySeq, ArrayStack, Buffer, BufferLike, IndexedSeq, IndexedSeqLike, IndexedSeqOptimized, IndexedSeqView, DroppedWhile, Filtered, Reversed, Sliced, TakenWhile, Transformed, LinearSeq, ListBuffer, MutableList, Queue, ResizableArray, Seq, SeqLike, StringBuilder, UnrolledBuffer, WrappedArray, ofBoolean, ofByte, ofChar, ofDouble, ofFloat, ofInt, ofLong, ofRef, ofShort, ofUnit, ParSeq, ParSeqLike, ParRange, ParSeq, ParVector, ParArray, ParSeq, SeqProxy, SeqProxyLike, SeqForwarder, PagedSeq, Stack, BufferProxy, DoubleLinkedList, DoubleLinkedListLike, LinkedList, LinkedListLike, ObservableBuffer, QueueProxy, Stack, StackProxy, SynchronizedBuffer, SynchronizedQueue, SynchronizedStack, Script
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Inherited
  1. GenSeqLike
  2. Equals
  3. GenIterableLike
  4. GenTraversableLike
  5. Parallelizable
  6. GenTraversableOnce
  7. Any
Implicitly
  1. by CollectionsHaveToParArray
  2. by any2stringadd
  3. by StringFormat
  4. by Ensuring
  5. by ArrowAssoc
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Abstract Value Members

  1. abstract def ++[B >: A, That](that: GenTraversableOnce[B])(implicit bf: CanBuildFrom[Repr, B, That]): That

    Returns a new general collection containing the elements from the left hand operand followed by the elements from the right hand operand.

    Returns a new general collection containing the elements from the left hand operand followed by the elements from the right hand operand. The element type of the general collection is the most specific superclass encompassing the element types of the two operands.

    B

    the element type of the returned collection.

    That

    the class of the returned collection. Where possible, That is the same class as the current collection class Repr, but this depends on the element type B being admissible for that class, which means that an implicit instance of type CanBuildFrom[Repr, B, That] is found.

    that

    the traversable to append.

    bf

    an implicit value of class CanBuildFrom which determines the result class That from the current representation type Repr and the new element type B.

    returns

    a new collection of type That which contains all elements of this general collection followed by all elements of that.

    Definition Classes
    GenTraversableLike
  2. abstract def aggregate[B](z: ⇒ B)(seqop: (B, A) ⇒ B, combop: (B, B) ⇒ B): B

    Aggregates the results of applying an operator to subsequent elements.

    Aggregates the results of applying an operator to subsequent elements.

    This is a more general form of fold and reduce. It is similar to foldLeft in that it doesn't require the result to be a supertype of the element type. In addition, it allows parallel collections to be processed in chunks, and then combines the intermediate results.

    aggregate splits the collection or iterator into partitions and processes each partition by sequentially applying seqop, starting with z (like foldLeft). Those intermediate results are then combined by using combop (like fold). The implementation of this operation may operate on an arbitrary number of collection partitions (even 1), so combop may be invoked an arbitrary number of times (even 0).

    As an example, consider summing up the integer values of a list of chars. The initial value for the sum is 0. First, seqop transforms each input character to an Int and adds it to the sum (of the partition). Then, combop just needs to sum up the intermediate results of the partitions:

    List('a', 'b', 'c').aggregate(0)({ (sum, ch) => sum + ch.toInt }, { (p1, p2) => p1 + p2 })
    B

    the type of accumulated results

    z

    the initial value for the accumulated result of the partition - this will typically be the neutral element for the seqop operator (e.g. Nil for list concatenation or 0 for summation) and may be evaluated more than once

    seqop

    an operator used to accumulate results within a partition

    combop

    an associative operator used to combine results from different partitions

    Definition Classes
    GenTraversableOnce
  3. abstract def apply(idx: Int): A

    Selects an element by its index in the general sequence.

    Selects an element by its index in the general sequence.

    Example:

    scala> val x = List(1, 2, 3, 4, 5)
    x: List[Int] = List(1, 2, 3, 4, 5)
    
    scala> x(3)
    res1: Int = 4
    idx

    The index to select.

    returns

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

    Exceptions thrown

    IndexOutOfBoundsException if idx does not satisfy 0 <= idx < length.

  4. abstract def canEqual(that: Any): Boolean

    A method that should be called from every well-designed equals method that is open to be overridden in a subclass.

    A method that should be called from every well-designed equals method that is open to be overridden in a subclass. See Programming in Scala, Chapter 28 for discussion and design.

    that

    the value being probed for possible equality

    returns

    true if this instance can possibly equal that, otherwise false

    Definition Classes
    Equals
  5. abstract def corresponds[B](that: GenSeq[B])(p: (A, B) ⇒ Boolean): Boolean

    Tests whether every element of this general sequence relates to the corresponding element of another sequence by satisfying a test predicate.

    Tests whether every element of this general sequence relates to the corresponding element of another sequence by satisfying a test predicate.

    B

    the type of the elements of that

    that

    the other sequence

    p

    the test predicate, which relates elements from both sequences

    returns

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

  6. abstract def count(p: (A) ⇒ Boolean): Int

    Counts the number of elements in the collection or iterator which satisfy a predicate.

    Counts the number of elements in the collection or iterator which satisfy a predicate.

    p

    the predicate used to test elements.

    returns

    the number of elements satisfying the predicate p.

    Definition Classes
    GenTraversableOnce
  7. abstract def distinct: Repr

    Builds a new general sequence from this general sequence without any duplicate elements.

    Builds a new general sequence from this general sequence without any duplicate elements.

    Note: will not terminate for infinite-sized collections.

    returns

    A new general sequence which contains the first occurrence of every element of this general sequence.

  8. abstract def drop(n: Int): Repr

    Selects all elements except first n ones.

    Selects all elements except first n ones.

    Note: might return different results for different runs, unless the underlying collection type is ordered.

    n

    the number of elements to drop from this general collection.

    returns

    a general collection consisting of all elements of this general collection except the first n ones, or else the empty general collection, if this general collection has less than n elements. If n is negative, don't drop any elements.

    Definition Classes
    GenTraversableLike
  9. abstract def dropWhile(pred: (A) ⇒ Boolean): Repr

    Drops longest prefix of elements that satisfy a predicate.

    Drops longest prefix of elements that satisfy a predicate.

    Note: might return different results for different runs, unless the underlying collection type is ordered.

    pred

    The predicate used to test elements.

    returns

    the longest suffix of this general collection whose first element does not satisfy the predicate p.

    Definition Classes
    GenTraversableLike
  10. abstract def endsWith[B](that: GenSeq[B]): Boolean

    Tests whether this general sequence ends with the given sequence.

    Tests whether this general sequence ends with the given sequence.

    Note: will not terminate for infinite-sized collections.

    that

    the sequence to test

    returns

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

  11. abstract def exists(p: (A) ⇒ Boolean): Boolean

    Tests whether a predicate holds for at least one element of this collection or iterator.

    Tests whether a predicate holds for at least one element of this collection or iterator.

    Note: may not terminate for infinite-sized collections.

    p

    the predicate used to test elements.

    returns

    true if the given predicate p is satisfied by at least one element of this collection or iterator, otherwise false

    Definition Classes
    GenTraversableOnce
  12. abstract def filter(pred: (A) ⇒ Boolean): Repr

    Selects all elements of this general collection which satisfy a predicate.

    Selects all elements of this general collection which satisfy a predicate.

    pred

    the predicate used to test elements.

    returns

    a new general collection consisting of all elements of this general collection that satisfy the given predicate p. Their order may not be preserved.

    Definition Classes
    GenTraversableLike
  13. abstract def filterNot(pred: (A) ⇒ Boolean): Repr

    Selects all elements of this general collection which do not satisfy a predicate.

    Selects all elements of this general collection which do not satisfy a predicate.

    pred

    the predicate used to test elements.

    returns

    a new general collection consisting of all elements of this general collection that do not satisfy the given predicate p. Their order may not be preserved.

    Definition Classes
    GenTraversableLike
  14. abstract def find(p: (A) ⇒ Boolean): Option[A]

    Finds the first element of the collection or iterator satisfying a predicate, if any.

    Finds the first element of the collection or iterator satisfying a predicate, if any.

    Note: may not terminate for infinite-sized collections.

    Note: might return different results for different runs, unless the underlying collection type is ordered.

    p

    the predicate used to test elements.

    returns

    an option value containing the first element in the collection or iterator that satisfies p, or None if none exists.

    Definition Classes
    GenTraversableOnce
  15. abstract def fold[A1 >: A](z: A1)(op: (A1, A1) ⇒ A1): A1

    Folds the elements of this collection or iterator using the specified associative binary operator.

    Folds the elements of this collection or iterator using the specified associative binary operator.

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

    Note: will not terminate for infinite-sized collections.

    A1

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

    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).

    op

    a binary operator that must be associative.

    returns

    the result of applying the fold operator op between all the elements and z, or z if this collection or iterator is empty.

    Definition Classes
    GenTraversableOnce
  16. abstract def foldLeft[B](z: B)(op: (B, A) ⇒ B): B

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

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

    Note: will not terminate for infinite-sized collections.

    Note: might return different results for different runs, unless the underlying collection type is ordered or the operator is associative and commutative.

    B

    the result type of the binary operator.

    z

    the start value.

    op

    the binary operator.

    returns

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

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

    where x1, ..., xn are the elements of this collection or iterator. Returns z if this collection or iterator is empty.

    Definition Classes
    GenTraversableOnce
  17. abstract def foldRight[B](z: B)(op: (A, B) ⇒ B): B

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

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

    Note: will not terminate for infinite-sized collections.

    Note: might return different results for different runs, unless the underlying collection type is ordered or the operator is associative and commutative.

    B

    the result type of the binary operator.

    z

    the start value.

    op

    the binary operator.

    returns

    the result of inserting op between consecutive elements of this collection or iterator, 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 collection or iterator. Returns z if this collection or iterator is empty.

    Definition Classes
    GenTraversableOnce
  18. abstract def forall(p: (A) ⇒ Boolean): Boolean

    Tests whether a predicate holds for all elements of this collection or iterator.

    Tests whether a predicate holds for all elements of this collection or iterator.

    Note: may not terminate for infinite-sized collections.

    p

    the predicate used to test elements.

    returns

    true if this collection or iterator is empty or the given predicate p holds for all elements of this collection or iterator, otherwise false.

    Definition Classes
    GenTraversableOnce
  19. abstract def getClass(): Class[_]

    Returns the runtime class representation of the object.

    Returns the runtime class representation of the object.

    returns

    a class object corresponding to the runtime type of the receiver.

    Definition Classes
    Any
  20. abstract def groupBy[K](f: (A) ⇒ K): GenMap[K, Repr]

    Partitions this general collection into a map of general collections according to some discriminator function.

    Partitions this general collection into a map of general collections according to some discriminator function.

    Note: this method is not re-implemented by views. This means when applied to a view it will always force the view and return a new general collection.

    K

    the type of keys returned by the discriminator function.

    f

    the discriminator function.

    returns

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

    (xs groupBy f)(k) = xs filter (x => f(x) == k)

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

    Definition Classes
    GenTraversableLike
  21. abstract def hasDefiniteSize: Boolean

    Tests whether this collection or iterator is known to have a finite size.

    Tests whether this collection or iterator is known to have a finite size. All strict collections are known to have finite size. For a non-strict collection such as Stream, the predicate returns true if all elements have been computed. It returns false if the stream is not yet evaluated to the end. Non-empty Iterators usually return false even if they were created from a collection with a known finite size.

    Note: many collection methods will not work on collections of infinite sizes. The typical failure mode is an infinite loop. These methods always attempt a traversal without checking first that hasDefiniteSize returns true. However, checking hasDefiniteSize can provide an assurance that size is well-defined and non-termination is not a concern.

    returns

    true if this collection is known to have finite size, false otherwise.

    Definition Classes
    GenTraversableOnce
  22. abstract def head: A

    Selects the first element of this general collection.

    Selects the first element of this general collection.

    Note: might return different results for different runs, unless the underlying collection type is ordered.

    returns

    the first element of this general collection.

    Definition Classes
    GenTraversableLike
    Exceptions thrown

    NoSuchElementException if the general collection is empty.

  23. abstract def headOption: Option[A]

    Optionally selects the first element.

    Optionally selects the first element.

    Note: might return different results for different runs, unless the underlying collection type is ordered.

    returns

    the first element of this general collection if it is nonempty, None if it is empty.

    Definition Classes
    GenTraversableLike
  24. abstract def indexWhere(p: (A) ⇒ 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.

    Note: may not terminate for infinite-sized collections.

    p

    the predicate used to test elements.

    from

    the start index

    returns

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

  25. abstract def init: Repr

    Selects all elements except the last.

    Selects all elements except the last.

    Note: might return different results for different runs, unless the underlying collection type is ordered.

    returns

    a general collection consisting of all elements of this general collection except the last one.

    Definition Classes
    GenTraversableLike
    Exceptions thrown

    UnsupportedOperationException if the general collection is empty.

  26. abstract def isEmpty: Boolean

    Tests whether the collection or iterator is empty.

    Tests whether the collection or iterator is empty.

    Note: Implementations in subclasses that are not repeatedly traversable must take care not to consume any elements when isEmpty is called.

    returns

    true if the collection or iterator contains no elements, false otherwise.

    Definition Classes
    GenTraversableOnce
  27. abstract def isTraversableAgain: Boolean

    Tests whether this general collection can be repeatedly traversed.

    Tests whether this general collection can be repeatedly traversed.

    returns

    true

    Definition Classes
    GenTraversableLikeGenTraversableOnce
  28. abstract def iterator: Iterator[A]
    Definition Classes
    GenIterableLike
  29. abstract def last: A

    Selects the last element.

    Selects the last element.

    Note: might return different results for different runs, unless the underlying collection type is ordered.

    returns

    The last element of this general collection.

    Definition Classes
    GenTraversableLike
    Exceptions thrown

    NoSuchElementException If the general collection is empty.

  30. abstract def lastIndexWhere(p: (A) ⇒ 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.

    p

    the predicate used to test elements.

    returns

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

  31. abstract def lastOption: Option[A]

    Optionally selects the last element.

    Optionally selects the last element.

    Note: might return different results for different runs, unless the underlying collection type is ordered.

    returns

    the last element of this general collection$ if it is nonempty, None if it is empty.

    Definition Classes
    GenTraversableLike
  32. abstract def length: Int

    The length of the general sequence.

    The length of the general sequence.

    Note: will not terminate for infinite-sized collections.

    Note: xs.length and xs.size yield the same result.

    returns

    the number of elements in this general sequence.

    Exceptions thrown

    IllegalArgumentException if the length of the sequence cannot be represented in an Int, for example, (-1 to Int.MaxValue).length.

  33. abstract def mkString: String

    Displays all elements of this collection or iterator in a string.

    Displays all elements of this collection or iterator in a string.

    returns

    a string representation of this collection or iterator. In the resulting string the string representations (w.r.t. the method toString) of all elements of this collection or iterator follow each other without any separator string.

    Definition Classes
    GenTraversableOnce
  34. abstract def mkString(sep: String): String

    Displays all elements of this collection or iterator in a string using a separator string.

    Displays all elements of this collection or iterator in a string using a separator string.

    sep

    the separator string.

    returns

    a string representation of this collection or iterator. In the resulting string the string representations (w.r.t. the method toString) of all elements of this collection or iterator are separated by the string sep.

    Definition Classes
    GenTraversableOnce
    Example:
    1. List(1, 2, 3).mkString("|") = "1|2|3"

  35. abstract def mkString(start: String, sep: String, end: String): String

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

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

    start

    the starting string.

    sep

    the separator string.

    end

    the ending string.

    returns

    a string representation of this collection or iterator. The resulting string begins with the string start and ends with the string end. Inside, the string representations (w.r.t. the method toString) of all elements of this collection or iterator are separated by the string sep.

    Definition Classes
    GenTraversableOnce
    Example:
    1. List(1, 2, 3).mkString("(", "; ", ")") = "(1; 2; 3)"

  36. abstract def nonEmpty: Boolean

    Tests whether the collection or iterator is not empty.

    Tests whether the collection or iterator is not empty.

    returns

    true if the collection or iterator contains at least one element, false otherwise.

    Definition Classes
    GenTraversableOnce
  37. abstract def parCombiner: Combiner[A, ParSeq[A]]

    The default par implementation uses the combiner provided by this method to create a new parallel collection.

    The default par implementation uses the combiner provided by this method to create a new parallel collection.

    returns

    a combiner for the parallel collection of type ParRepr

    Attributes
    protected[this]
    Definition Classes
    Parallelizable
  38. abstract def partition(pred: (A) ⇒ Boolean): (Repr, Repr)

    Partitions this general collection in two general collections according to a predicate.

    Partitions this general collection in two general collections according to a predicate.

    pred

    the predicate on which to partition.

    returns

    a pair of general collections: the first general collection consists of all elements that satisfy the predicate p and the second general collection consists of all elements that don't. The relative order of the elements in the resulting general collections may not be preserved.

    Definition Classes
    GenTraversableLike
  39. abstract def reduce[A1 >: A](op: (A1, A1) ⇒ A1): A1

    Reduces the elements of this collection or iterator using the specified associative binary operator.

    Reduces the elements of this collection or iterator using the specified associative binary operator.

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

    A1

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

    op

    A binary operator that must be associative.

    returns

    The result of applying reduce operator op between all the elements if the collection or iterator is nonempty.

    Definition Classes
    GenTraversableOnce
    Exceptions thrown

    UnsupportedOperationException if this collection or iterator is empty.

  40. abstract def reduceLeftOption[B >: A](op: (B, A) ⇒ B): Option[B]

    Optionally applies a binary operator to all elements of this collection or iterator, going left to right.

    Optionally applies a binary operator to all elements of this collection or iterator, going left to right.

    Note: will not terminate for infinite-sized collections.

    Note: might return different results for different runs, unless the underlying collection type is ordered or the operator is associative and commutative.

    B

    the result type of the binary operator.

    op

    the binary operator.

    returns

    an option value containing the result of reduceLeft(op) if this collection or iterator is nonempty, None otherwise.

    Definition Classes
    GenTraversableOnce
  41. abstract def reduceOption[A1 >: A](op: (A1, A1) ⇒ A1): Option[A1]

    Reduces the elements of this collection or iterator, if any, using the specified associative binary operator.

    Reduces the elements of this collection or iterator, if any, using the specified associative binary operator.

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

    A1

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

    op

    A binary operator that must be associative.

    returns

    An option value containing result of applying reduce operator op between all the elements if the collection is nonempty, and None otherwise.

    Definition Classes
    GenTraversableOnce
  42. abstract def reduceRight[B >: A](op: (A, B) ⇒ B): B

    Applies a binary operator to all elements of this collection or iterator, going right to left.

    Applies a binary operator to all elements of this collection or iterator, going right to left.

    Note: will not terminate for infinite-sized collections.

    Note: might return different results for different runs, unless the underlying collection type is ordered or the operator is associative and commutative.

    B

    the result type of the binary operator.

    op

    the binary operator.

    returns

    the result of inserting op between consecutive elements of this collection or iterator, going right to left:

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

    where x1, ..., xn are the elements of this collection or iterator.

    Definition Classes
    GenTraversableOnce
    Exceptions thrown

    UnsupportedOperationException if this collection or iterator is empty.

  43. abstract def reduceRightOption[B >: A](op: (A, B) ⇒ B): Option[B]

    Optionally applies a binary operator to all elements of this collection or iterator, going right to left.

    Optionally applies a binary operator to all elements of this collection or iterator, going right to left.

    Note: will not terminate for infinite-sized collections.

    Note: might return different results for different runs, unless the underlying collection type is ordered or the operator is associative and commutative.

    B

    the result type of the binary operator.

    op

    the binary operator.

    returns

    an option value containing the result of reduceRight(op) if this collection or iterator is nonempty, None otherwise.

    Definition Classes
    GenTraversableOnce
  44. abstract def repr: Repr
    Definition Classes
    GenTraversableLike
  45. abstract def reverse: Repr

    Returns new general sequence with elements in reversed order.

    Returns new general sequence with elements in reversed order.

    Note: will not terminate for infinite-sized collections.

    returns

    A new general sequence with all elements of this general sequence in reversed order.

  46. abstract def scan[B >: A, That](z: B)(op: (B, B) ⇒ B)(implicit cbf: CanBuildFrom[Repr, B, That]): That

    Computes a prefix scan of the elements of the collection.

    Computes a prefix scan of the elements of the collection.

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

    B

    element type of the resulting collection

    That

    type of the resulting collection

    z

    neutral element for the operator op

    op

    the associative operator for the scan

    cbf

    combiner factory which provides a combiner

    returns

    a new general collection containing the prefix scan of the elements in this general collection

    Definition Classes
    GenTraversableLike
  47. abstract def scanLeft[B, That](z: B)(op: (B, A) ⇒ B)(implicit bf: CanBuildFrom[Repr, B, That]): That

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

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

    Note: will not terminate for infinite-sized collections.

    Note: might return different results for different runs, unless the underlying collection type is ordered.

    B

    the type of the elements in the resulting collection

    That

    the actual type of the resulting collection

    z

    the initial value

    op

    the binary operator applied to the intermediate result and the element

    bf

    an implicit value of class CanBuildFrom which determines the result class That from the current representation type Repr and the new element type B.

    returns

    collection with intermediate results

    Definition Classes
    GenTraversableLike
  48. abstract def scanRight[B, That](z: B)(op: (A, B) ⇒ B)(implicit bf: CanBuildFrom[Repr, B, That]): That

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

    Produces a collection containing cumulative results of applying the operator going right to left. The head of the collection is the last cumulative result.

    Note: will not terminate for infinite-sized collections.

    Note: might return different results for different runs, unless the underlying collection type is ordered.

    Example:

    List(1, 2, 3, 4).scanRight(0)(_ + _) == List(10, 9, 7, 4, 0)
    B

    the type of the elements in the resulting collection

    That

    the actual type of the resulting collection

    z

    the initial value

    op

    the binary operator applied to the intermediate result and the element

    bf

    an implicit value of class CanBuildFrom which determines the result class That from the current representation type Repr and the new element type B.

    returns

    collection with intermediate results

    Definition Classes
    GenTraversableLike
    Annotations
    @migration
    Migration

    (Changed in version 2.9.0) The behavior of scanRight has changed. The previous behavior can be reproduced with scanRight.reverse.

  49. abstract def segmentLength(p: (A) ⇒ 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.

    Note: may not terminate for infinite-sized collections.

    p

    the predicate used to test elements.

    from

    the index where the search starts.

    returns

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

  50. abstract def seq: Seq[A]
    Definition Classes
    GenSeqLikeParallelizableGenTraversableOnce
  51. abstract def size: Int

    The size of this general collection.

    The size of this general collection.

    Note: will not terminate for infinite-sized collections.

    returns

    the number of elements in this general collection.

    Definition Classes
    GenTraversableLikeGenTraversableOnce
  52. abstract def slice(unc_from: Int, unc_until: Int): Repr

    Selects an interval of elements.

    Selects an interval of elements. The returned collection is made up of all elements x which satisfy the invariant:

    from <= indexOf(x) < until

    Note: might return different results for different runs, unless the underlying collection type is ordered.

    unc_from

    the lowest index to include from this general collection.

    unc_until

    the lowest index to EXCLUDE from this general collection.

    returns

    a general collection containing the elements greater than or equal to index from extending up to (but not including) index until of this general collection.

    Definition Classes
    GenTraversableLike
  53. abstract def span(pred: (A) ⇒ Boolean): (Repr, Repr)

    Splits this general collection into a prefix/suffix pair according to a predicate.

    Splits this general collection into a prefix/suffix pair according to a predicate.

    Note: c span p is equivalent to (but possibly more efficient than) (c takeWhile p, c dropWhile p), provided the evaluation of the predicate p does not cause any side-effects.

    Note: might return different results for different runs, unless the underlying collection type is ordered.

    pred

    the test predicate

    returns

    a pair consisting of the longest prefix of this general collection whose elements all satisfy p, and the rest of this general collection.

    Definition Classes
    GenTraversableLike
  54. abstract def splitAt(n: Int): (Repr, Repr)

    Splits this general collection into two at a given position.

    Splits this general collection into two at a given position. Note: c splitAt n is equivalent to (but possibly more efficient than) (c take n, c drop n).

    Note: might return different results for different runs, unless the underlying collection type is ordered.

    n

    the position at which to split.

    returns

    a pair of general collections consisting of the first n elements of this general collection, and the other elements.

    Definition Classes
    GenTraversableLike
  55. abstract def startsWith[B](that: GenSeq[B], offset: Int): Boolean

    Tests whether this general sequence contains the given sequence at a given index.

    Tests whether this general sequence contains the given sequence at a given index.

    Note: If the both the receiver object this and the argument that are infinite sequences this method may not terminate.

    that

    the sequence to test

    offset

    the index where the sequence is searched.

    returns

    true if the sequence that is contained in this general sequence at index offset, otherwise false.

  56. abstract def stringPrefix: String

    Defines the prefix of this object's toString representation.

    Defines the prefix of this object's toString representation.

    returns

    a string representation which starts the result of toString applied to this general collection. By default the string prefix is the simple name of the collection class general collection.

    Definition Classes
    GenTraversableLike
  57. abstract def tail: Repr

    Selects all elements except the first.

    Selects all elements except the first.

    Note: might return different results for different runs, unless the underlying collection type is ordered.

    returns

    a general collection consisting of all elements of this general collection except the first one.

    Definition Classes
    GenTraversableLike
    Exceptions thrown

    UnsupportedOperationException if the general collection is empty.

  58. abstract def take(n: Int): Repr

    Selects first n elements.

    Selects first n elements.

    Note: might return different results for different runs, unless the underlying collection type is ordered.

    n

    the number of elements to take from this general collection.

    returns

    a general collection consisting only of the first n elements of this general collection, or else the whole general collection, if it has less than n elements. If n is negative, returns an empty general collection.

    Definition Classes
    GenTraversableLike
  59. abstract def takeWhile(pred: (A) ⇒ Boolean): Repr

    Takes longest prefix of elements that satisfy a predicate.

    Takes longest prefix of elements that satisfy a predicate.

    Note: might return different results for different runs, unless the underlying collection type is ordered.

    pred

    The predicate used to test elements.

    returns

    the longest prefix of this general collection whose elements all satisfy the predicate p.

    Definition Classes
    GenTraversableLike
  60. abstract def toBuffer[A1 >: A]: Buffer[A1]

    Uses the contents of this collection or iterator to create a new mutable buffer.

    Uses the contents of this collection or iterator to create a new mutable buffer.

    Note: will not terminate for infinite-sized collections.

    returns

    a buffer containing all elements of this collection or iterator.

    Definition Classes
    GenTraversableOnce
  61. abstract def toIndexedSeq: immutable.IndexedSeq[A]

    Converts this collection or iterator to an indexed sequence.

    Converts this collection or iterator to an indexed sequence.

    Note: will not terminate for infinite-sized collections.

    returns

    an indexed sequence containing all elements of this collection or iterator.

    Definition Classes
    GenTraversableOnce
  62. abstract def toIterable: GenIterable[A]

    Converts this collection or iterator to an iterable collection.

    Converts this collection or iterator to an iterable collection. Note that the choice of target Iterable is lazy in this default implementation as this TraversableOnce may be lazy and unevaluated (i.e. it may be an iterator which is only traversable once).

    Note: will not terminate for infinite-sized collections.

    returns

    an Iterable containing all elements of this collection or iterator.

    Definition Classes
    GenTraversableOnce
  63. abstract def toIterator: Iterator[A]

    Returns an Iterator over the elements in this collection or iterator.

    Returns an Iterator over the elements in this collection or iterator. Will return the same Iterator if this instance is already an Iterator.

    Note: will not terminate for infinite-sized collections.

    returns

    an Iterator containing all elements of this collection or iterator.

    Definition Classes
    GenTraversableOnce
  64. abstract def toList: List[A]

    Converts this collection or iterator to a list.

    Converts this collection or iterator to a list.

    Note: will not terminate for infinite-sized collections.

    returns

    a list containing all elements of this collection or iterator.

    Definition Classes
    GenTraversableOnce
  65. abstract def toSeq: GenSeq[A]

    Converts this general sequence to a sequence.

    Converts this general sequence to a sequence. As with toIterable, it's lazy in this default implementation, as this TraversableOnce may be lazy and unevaluated.

    Note: will not terminate for infinite-sized collections.

    returns

    a sequence containing all elements of this general sequence.

    Definition Classes
    GenSeqLikeGenTraversableOnce
  66. abstract def toSet[A1 >: A]: GenSet[A1]

    Converts this collection or iterator to a set.

    Converts this collection or iterator to a set.

    Note: will not terminate for infinite-sized collections.

    returns

    a set containing all elements of this collection or iterator.

    Definition Classes
    GenTraversableOnce
  67. abstract def toStream: Stream[A]

    Converts this collection or iterator to a stream.

    Converts this collection or iterator to a stream.

    returns

    a stream containing all elements of this collection or iterator.

    Definition Classes
    GenTraversableOnce
  68. abstract def toTraversable: GenTraversable[A]

    Converts this collection or iterator to an unspecified Traversable.

    Converts this collection or iterator to an unspecified Traversable. Will return the same collection if this instance is already Traversable.

    Note: will not terminate for infinite-sized collections.

    returns

    a Traversable containing all elements of this collection or iterator.

    Definition Classes
    GenTraversableOnce
  69. abstract def toVector: Vector[A]

    Converts this collection or iterator to a Vector.

    Converts this collection or iterator to a Vector.

    Note: will not terminate for infinite-sized collections.

    returns

    a vector containing all elements of this collection or iterator.

    Definition Classes
    GenTraversableOnce
  70. abstract def /:[B](z: B)(op: (B, A) ⇒ B): B

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

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

    Note: /: is alternate syntax for foldLeft; z /: xs is the same as xs foldLeft z.

    Examples:

    Note that the folding function used to compute b is equivalent to that used to compute c.

    scala> val a = List(1,2,3,4)
    a: List[Int] = List(1, 2, 3, 4)
    
    scala> val b = (5 /: a)(_+_)
    b: Int = 15
    
    scala> val c = (5 /: a)((x,y) => x + y)
    c: Int = 15

    Note: will not terminate for infinite-sized collections.

    Note: might return different results for different runs, unless the underlying collection type is ordered or the operator is associative and commutative.

    B

    the result type of the binary operator.

    z

    the start value.

    op

    the binary operator.

    returns

    the result of inserting op between consecutive elements of this collection or iterator, 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 collection or iterator.

    Definition Classes
    GenTraversableOnce
    Annotations
    @deprecated
    Deprecated

    (Since version 2.12.10) Use foldLeft instead of /:

  71. abstract def :\[B](z: B)(op: (A, B) ⇒ B): B

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

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

    Note: :\ is alternate syntax for foldRight; xs :\ z is the same as xs foldRight z.

    Note: will not terminate for infinite-sized collections.

    Note: might return different results for different runs, unless the underlying collection type is ordered or the operator is associative and commutative.

    Examples:

    Note that the folding function used to compute b is equivalent to that used to compute c.

    scala> val a = List(1,2,3,4)
    a: List[Int] = List(1, 2, 3, 4)
    
    scala> val b = (a :\ 5)(_+_)
    b: Int = 15
    
    scala> val c = (a :\ 5)((x,y) => x + y)
    c: Int = 15
    B

    the result type of the binary operator.

    z

    the start value

    op

    the binary operator

    returns

    the result of inserting op between consecutive elements of this collection or iterator, 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 collection or iterator.

    Definition Classes
    GenTraversableOnce
    Annotations
    @deprecated
    Deprecated

    (Since version 2.12.10) Use foldRight instead of :\

Concrete Value Members

  1. final def !=(arg0: Any): Boolean

    Test two objects for inequality.

    Test two objects for inequality.

    returns

    true if !(this == that), false otherwise.

    Definition Classes
    Any
  2. final def ##(): Int

    Equivalent to x.hashCode except for boxed numeric types and null.

    Equivalent to x.hashCode except for boxed numeric types and null. For numerics, it returns a hash value which is consistent with value equality: if two value type instances compare as true, then ## will produce the same hash value for each of them. For null returns a hashcode where null.hashCode throws a NullPointerException.

    returns

    a hash value consistent with ==

    Definition Classes
    Any
  3. def +(other: String): String
    Implicit
    This member is added by an implicit conversion from GenSeqLike[A, Repr] to any2stringadd[GenSeqLike[A, Repr]] performed by method any2stringadd in scala.Predef.
    Definition Classes
    any2stringadd
  4. abstract def +:(elem: A): GenSeq[A]

    [use case] A copy of the general sequence with an element prepended.

    [use case]

    A copy of the general sequence with an element prepended.

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

    Also, the original general sequence is not modified, so you will want to capture the result.

    Example:

    scala> val x = List(1)
    x: List[Int] = List(1)
    
    scala> val y = 2 +: x
    y: List[Int] = List(2, 1)
    
    scala> println(x)
    List(1)
    elem

    the prepended element

    returns

    a new general sequence consisting of elem followed by all elements of this general sequence.

    Full Signature

    abstract def +:[B >: A, That](elem: B)(implicit bf: CanBuildFrom[Repr, B, That]): That

  5. def ->[B](y: B): (GenSeqLike[A, Repr], B)
    Implicit
    This member is added by an implicit conversion from GenSeqLike[A, Repr] to ArrowAssoc[GenSeqLike[A, Repr]] performed by method ArrowAssoc in scala.Predef.
    Definition Classes
    ArrowAssoc
    Annotations
    @inline()
  6. abstract def :+(elem: A): GenSeq[A]

    [use case] A copy of this general sequence with an element appended.

    [use case]

    A copy of this general sequence with an element appended.

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

    Note: will not terminate for infinite-sized collections.

    Example:

    scala> val a = List(1)
    a: List[Int] = List(1)
    
    scala> val b = a :+ 2
    b: List[Int] = List(1, 2)
    
    scala> println(a)
    List(1)
    elem

    the appended element

    returns

    a new general sequence consisting of all elements of this general sequence followed by elem.

    Full Signature

    abstract def :+[B >: A, That](elem: B)(implicit bf: CanBuildFrom[Repr, B, That]): That

  7. final def ==(arg0: Any): Boolean

    Test two objects for equality.

    Test two objects for equality. The expression x == that is equivalent to if (x eq null) that eq null else x.equals(that).

    returns

    true if the receiver object is equivalent to the argument; false otherwise.

    Definition Classes
    Any
  8. final def asInstanceOf[T0]: T0

    Cast the receiver object to be of type T0.

    Cast the receiver object to be of type T0.

    Note that the success of a cast at runtime is modulo Scala's erasure semantics. Therefore the expression 1.asInstanceOf[String] will throw a ClassCastException at runtime, while the expression List(1).asInstanceOf[List[String]] will not. In the latter example, because the type argument is erased as part of compilation it is not possible to check whether the contents of the list are of the requested type.

    returns

    the receiver object.

    Definition Classes
    Any
    Exceptions thrown

    ClassCastException if the receiver object is not an instance of the erasure of type T0.

  9. abstract def collect[B](pf: PartialFunction[A, B]): GenSeq[B]

    [use case] Builds a new collection by applying a partial function to all elements of this general sequence on which the function is defined.

    [use case]

    Builds a new collection by applying a partial function to all elements of this general sequence on which the function is defined.

    B

    the element type of the returned collection.

    pf

    the partial function which filters and maps the general sequence.

    returns

    a new general sequence resulting from applying the given partial function pf to each element on which it is defined and collecting the results. The order of the elements is preserved.

    Definition Classes
    GenTraversableLike
    Full Signature

    abstract def collect[B, That](pf: PartialFunction[A, B])(implicit bf: CanBuildFrom[Repr, B, That]): That

  10. abstract def copyToArray(xs: Array[A], start: Int, len: Int): Unit

    [use case] Copies the elements of this general sequence to an array.

    [use case]

    Copies the elements of this general sequence to an array. Fills the given array xs with at most len elements of this general sequence, starting at position start. Copying will stop once either the end of the current general sequence is reached, or the end of the target array is reached, or len elements have been copied.

    Note: will not terminate for infinite-sized collections.

    xs

    the array to fill.

    start

    the starting index.

    len

    the maximal number of elements to copy.

    Definition Classes
    GenTraversableOnce
    Full Signature

    abstract def copyToArray[B >: A](xs: Array[B], start: Int, len: Int): Unit

  11. abstract def copyToArray(xs: Array[A], start: Int): Unit

    [use case] Copies the elements of this general sequence to an array.

    [use case]

    Copies the elements of this general sequence to an array. Fills the given array xs with values of this general sequence, beginning at index start. Copying will stop once either the end of the current general sequence is reached, or the end of the target array is reached.

    Note: will not terminate for infinite-sized collections.

    xs

    the array to fill.

    start

    the starting index.

    Definition Classes
    GenTraversableOnce
    Full Signature

    abstract def copyToArray[B >: A](xs: Array[B], start: Int): Unit

  12. abstract def copyToArray(xs: Array[A]): Unit

    [use case] Copies the elements of this general sequence to an array.

    [use case]

    Copies the elements of this general sequence to an array. Fills the given array xs with values of this general sequence. Copying will stop once either the end of the current general sequence is reached, or the end of the target array is reached.

    Note: will not terminate for infinite-sized collections.

    xs

    the array to fill.

    Definition Classes
    GenTraversableOnce
    Full Signature

    abstract def copyToArray[B >: A](xs: Array[B]): Unit

  13. abstract def diff(that: GenSeq[A]): GenSeq[A]

    [use case] Computes the multiset difference between this general sequence and another sequence.

    [use case]

    Computes the multiset difference between this general sequence and another sequence.

    Note: will not terminate for infinite-sized collections.

    that

    the sequence of elements to remove

    returns

    a new general sequence which contains all elements of this general sequence except some of occurrences of elements that also appear in that. If an element value x appears n times in that, then the first n occurrences of x will not form part of the result, but any following occurrences will.

    Full Signature

    abstract def diff[B >: A](that: GenSeq[B]): Repr

  14. def ensuring(cond: (GenSeqLike[A, Repr]) ⇒ Boolean, msg: ⇒ Any): GenSeqLike[A, Repr]
    Implicit
    This member is added by an implicit conversion from GenSeqLike[A, Repr] to Ensuring[GenSeqLike[A, Repr]] performed by method Ensuring in scala.Predef.
    Definition Classes
    Ensuring
  15. def ensuring(cond: (GenSeqLike[A, Repr]) ⇒ Boolean): GenSeqLike[A, Repr]
    Implicit
    This member is added by an implicit conversion from GenSeqLike[A, Repr] to Ensuring[GenSeqLike[A, Repr]] performed by method Ensuring in scala.Predef.
    Definition Classes
    Ensuring
  16. def ensuring(cond: Boolean, msg: ⇒ Any): GenSeqLike[A, Repr]
    Implicit
    This member is added by an implicit conversion from GenSeqLike[A, Repr] to Ensuring[GenSeqLike[A, Repr]] performed by method Ensuring in scala.Predef.
    Definition Classes
    Ensuring
  17. def ensuring(cond: Boolean): GenSeqLike[A, Repr]
    Implicit
    This member is added by an implicit conversion from GenSeqLike[A, Repr] to Ensuring[GenSeqLike[A, Repr]] performed by method Ensuring in scala.Predef.
    Definition Classes
    Ensuring
  18. def equals(that: Any): Boolean

    The equals method for arbitrary sequences.

    The equals method for arbitrary sequences. Compares this sequence to some other object.

    that

    The object to compare the sequence to

    returns

    true if that is a sequence that has the same elements as this sequence in the same order, false otherwise

    Definition Classes
    GenSeqLikeEqualsAny
  19. abstract def flatMap[B](f: (A) ⇒ GenTraversableOnce[B]): GenSeq[B]

    [use case] Builds a new collection by applying a function to all elements of this general sequence and using the elements of the resulting collections.

    [use case]

    Builds a new collection by applying a function to all elements of this general sequence and using the elements of the resulting collections.

    For example:

    def getWords(lines: Seq[String]): Seq[String] = lines flatMap (line => line split "\\W+")

    The type of the resulting collection is guided by the static type of general sequence. This might cause unexpected results sometimes. For example:

    // lettersOf will return a Seq[Char] of likely repeated letters, instead of a Set
    def lettersOf(words: Seq[String]) = words flatMap (word => word.toSet)
    
    // lettersOf will return a Set[Char], not a Seq
    def lettersOf(words: Seq[String]) = words.toSet flatMap (word => word.toSeq)
    
    // xs will be an Iterable[Int]
    val xs = Map("a" -> List(11,111), "b" -> List(22,222)).flatMap(_._2)
    
    // ys will be a Map[Int, Int]
    val ys = Map("a" -> List(1 -> 11,1 -> 111), "b" -> List(2 -> 22,2 -> 222)).flatMap(_._2)
    B

    the element type of the returned collection.

    f

    the function to apply to each element.

    returns

    a new general sequence resulting from applying the given collection-valued function f to each element of this general sequence and concatenating the results.

    Definition Classes
    GenTraversableLike
    Full Signature

    abstract def flatMap[B, That](f: (A) ⇒ GenTraversableOnce[B])(implicit bf: CanBuildFrom[Repr, B, That]): That

  20. abstract def foreach(f: (A) ⇒ Unit): Unit

    [use case] Applies a function f to all elements of this general sequence.

    [use case]

    Applies a function f to all elements of this general sequence.

    Note: this method underlies the implementation of most other bulk operations. It's important to implement this method in an efficient way.

    f

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

    Definition Classes
    GenTraversableLikeGenTraversableOnce
    Full Signature

    abstract def foreach[U](f: (A) ⇒ U): Unit

  21. def formatted(fmtstr: String): String

    Returns string formatted according to given format string.

    Returns string formatted according to given format string. Format strings are as for String.format (@see java.lang.String.format).

    Implicit
    This member is added by an implicit conversion from GenSeqLike[A, Repr] to StringFormat[GenSeqLike[A, Repr]] performed by method StringFormat in scala.Predef.
    Definition Classes
    StringFormat
    Annotations
    @inline()
  22. def hashCode(): Int

    Hashcodes for GenSeq produce a value from the hashcodes of all the elements of the general sequence.

    Hashcodes for GenSeq produce a value from the hashcodes of all the elements of the general sequence.

    returns

    the hash code value for this object.

    Definition Classes
    GenSeqLikeAny
  23. def indexOf(elem: A, from: Int): Int

    [use case] Finds index of first occurrence of some value in this general sequence after or at some start index.

    [use case]

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

    Note: may not terminate for infinite-sized collections.

    elem

    the element value to search for.

    from

    the start index

    returns

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

    Full Signature

    def indexOf[B >: A](elem: B, from: Int): Int

  24. def indexOf(elem: A): Int

    [use case] Finds index of first occurrence of some value in this general sequence.

    [use case]

    Finds index of first occurrence of some value in this general sequence.

    Note: may not terminate for infinite-sized collections.

    elem

    the element value to search for.

    returns

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

    Full Signature

    def indexOf[B >: A](elem: B): Int

  25. def indexWhere(p: (A) ⇒ Boolean): Int

    Finds index of first element satisfying some predicate.

    Finds index of first element satisfying some predicate.

    Note: may not terminate for infinite-sized collections.

    p

    the predicate used to test elements.

    returns

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

  26. abstract def intersect(that: GenSeq[A]): GenSeq[A]

    [use case] Computes the multiset intersection between this general sequence and another sequence.

    [use case]

    Computes the multiset intersection between this general sequence and another sequence.

    Note: may not terminate for infinite-sized collections.

    that

    the sequence of elements to intersect with.

    returns

    a new general sequence which contains all elements of this general sequence which also appear in that. If an element value x appears n times in that, then the first n occurrences of x will be retained in the result, but any following occurrences will be omitted.

    Full Signature

    abstract def intersect[B >: A](that: GenSeq[B]): Repr

  27. def isDefinedAt(idx: Int): Boolean

    Tests whether this general sequence contains given index.

    Tests whether this general sequence contains given index.

    The implementations of methods apply and isDefinedAt turn a Seq[A] into a PartialFunction[Int, A].

    idx

    the index to test

    returns

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

  28. final def isInstanceOf[T0]: Boolean

    Test whether the dynamic type of the receiver object is T0.

    Test whether the dynamic type of the receiver object is T0.

    Note that the result of the test is modulo Scala's erasure semantics. Therefore the expression 1.isInstanceOf[String] will return false, while the expression List(1).isInstanceOf[List[String]] will return true. In the latter example, because the type argument is erased as part of compilation it is not possible to check whether the contents of the list are of the specified type.

    returns

    true if the receiver object is an instance of erasure of type T0; false otherwise.

    Definition Classes
    Any
  29. def lastIndexOf(elem: A, end: Int): Int

    [use case] Finds index of last occurrence of some value in this general sequence before or at a given end index.

    [use case]

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

    elem

    the element value to search for.

    end

    the end index.

    returns

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

    Full Signature

    def lastIndexOf[B >: A](elem: B, end: Int): Int

  30. def lastIndexOf(elem: A): Int

    [use case] Finds index of last occurrence of some value in this general sequence.

    [use case]

    Finds index of last occurrence of some value in this general sequence.

    Note: will not terminate for infinite-sized collections.

    elem

    the element value to search for.

    returns

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

    Full Signature

    def lastIndexOf[B >: A](elem: B): Int

  31. def lastIndexWhere(p: (A) ⇒ Boolean): Int

    Finds index of last element satisfying some predicate.

    Finds index of last element satisfying some predicate.

    Note: will not terminate for infinite-sized collections.

    p

    the predicate used to test elements.

    returns

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

  32. abstract def map[B](f: (A) ⇒ B): GenSeq[B]

    [use case] Builds a new collection by applying a function to all elements of this general sequence.

    [use case]

    Builds a new collection by applying a function to all elements of this general sequence.

    B

    the element type of the returned collection.

    f

    the function to apply to each element.

    returns

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

    Definition Classes
    GenTraversableLike
    Full Signature

    abstract def map[B, That](f: (A) ⇒ B)(implicit bf: CanBuildFrom[Repr, B, That]): That

  33. abstract def max: A

    [use case] Finds the largest element.

    [use case]

    Finds the largest element.

    returns

    the largest element of this general sequence.

    Definition Classes
    GenTraversableOnce
    Full Signature

    abstract def max[A1 >: A](implicit ord: Ordering[A1]): A

    Exceptions thrown

    UnsupportedOperationException if this general sequence is empty.

  34. abstract def maxBy[B](f: (A) ⇒ B): A

    [use case] Finds the first element which yields the largest value measured by function f.

    [use case]

    Finds the first element which yields the largest value measured by function f.

    B

    The result type of the function f.

    f

    The measuring function.

    returns

    the first element of this general sequence with the largest value measured by function f.

    Definition Classes
    GenTraversableOnce
    Full Signature

    abstract def maxBy[B](f: (A) ⇒ B)(implicit cmp: Ordering[B]): A

    Exceptions thrown

    UnsupportedOperationException if this general sequence is empty.

  35. abstract def min: A

    [use case] Finds the smallest element.

    [use case]

    Finds the smallest element.

    returns

    the smallest element of this general sequence

    Definition Classes
    GenTraversableOnce
    Full Signature

    abstract def min[A1 >: A](implicit ord: Ordering[A1]): A

    Exceptions thrown

    UnsupportedOperationException if this general sequence is empty.

  36. abstract def minBy[B](f: (A) ⇒ B): A

    [use case] Finds the first element which yields the smallest value measured by function f.

    [use case]

    Finds the first element which yields the smallest value measured by function f.

    B

    The result type of the function f.

    f

    The measuring function.

    returns

    the first element of this general sequence with the smallest value measured by function f.

    Definition Classes
    GenTraversableOnce
    Full Signature

    abstract def minBy[B](f: (A) ⇒ B)(implicit cmp: Ordering[B]): A

    Exceptions thrown

    UnsupportedOperationException if this general sequence is empty.

  37. abstract def padTo(len: Int, elem: A): GenSeq[A]

    [use case] A copy of this general sequence with an element value appended until a given target length is reached.

    [use case]

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

    len

    the target length

    elem

    the padding value

    returns

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

    Full Signature

    abstract def padTo[B >: A, That](len: Int, elem: B)(implicit bf: CanBuildFrom[Repr, B, That]): That

  38. def par: ParSeq[A]

    Returns a parallel implementation of this collection.

    Returns a parallel implementation of this collection.

    For most collection types, this method creates a new parallel collection by copying all the elements. For these collection, par takes linear time. Mutable collections in this category do not produce a mutable parallel collection that has the same underlying dataset, so changes in one collection will not be reflected in the other one.

    Specific collections (e.g. ParArray or mutable.ParHashMap) override this default behaviour by creating a parallel collection which shares the same underlying dataset. For these collections, par takes constant or sublinear time.

    All parallel collections return a reference to themselves.

    returns

    a parallel implementation of this collection

    Definition Classes
    Parallelizable
  39. abstract def patch(from: Int, that: GenSeq[A], replaced: Int): GenSeq[A]

    [use case] Produces a new general sequence where a slice of elements in this general sequence is replaced by another sequence.

    [use case]

    Produces a new general sequence where a slice of elements in this general sequence is replaced by another sequence.

    from

    the index of the first replaced element

    replaced

    the number of elements to drop in the original general sequence

    returns

    a new general sequence consisting of all elements of this general sequence except that replaced elements starting from from are replaced by patch.

    Full Signature

    abstract def patch[B >: A, That](from: Int, patch: GenSeq[B], replaced: Int)(implicit bf: CanBuildFrom[Repr, B, That]): That

  40. def prefixLength(p: (A) ⇒ 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.

    Note: may not terminate for infinite-sized collections.

    p

    the predicate used to test elements.

    returns

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

  41. abstract def product: A

    [use case] Multiplies up the elements of this collection.

    [use case]

    Multiplies up the elements of this collection.

    returns

    the product of all elements in this general sequence of numbers of type Int. Instead of Int, any other type T with an implicit Numeric[T] implementation can be used as element type of the general sequence and as result type of product. Examples of such types are: Long, Float, Double, BigInt.

    Definition Classes
    GenTraversableOnce
    Full Signature

    abstract def product[A1 >: A](implicit num: Numeric[A1]): A1

  42. abstract def reverseMap[B](f: (A) ⇒ B): GenSeq[B]

    [use case] Builds a new collection by applying a function to all elements of this general sequence and collecting the results in reversed order.

    [use case]

    Builds a new collection by applying a function to all elements of this general sequence and collecting the results in reversed order.

    Note: will not terminate for infinite-sized collections.

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

    B

    the element type of the returned collection.

    f

    the function to apply to each element.

    returns

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

    Full Signature

    abstract def reverseMap[B, That](f: (A) ⇒ B)(implicit bf: CanBuildFrom[Repr, B, That]): That

  43. abstract def sameElements(that: GenIterable[A]): Boolean

    [use case] Checks if the other iterable collection contains the same elements in the same order as this general sequence.

    [use case]

    Checks if the other iterable collection contains the same elements in the same order as this general sequence.

    Note: might return different results for different runs, unless the underlying collection type is ordered.

    Note: will not terminate for infinite-sized collections.

    that

    the collection to compare with.

    returns

    true, if both collections contain the same elements in the same order, false otherwise.

    Definition Classes
    GenIterableLike
    Full Signature

    abstract def sameElements[A1 >: A](that: GenIterable[A1]): Boolean

  44. def sizeHintIfCheap: Int

    The size of this collection or iterator, if it can be cheaply computed

    The size of this collection or iterator, if it can be cheaply computed

    returns

    the number of elements in this collection or iterator, or -1 if the size cannot be determined cheaply

    Attributes
    protected[collection]
    Definition Classes
    GenTraversableOnce
  45. def startsWith[B](that: GenSeq[B]): Boolean

    Tests whether this general sequence starts with the given sequence.

    Tests whether this general sequence starts with the given sequence.

    that

    the sequence to test

    returns

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

  46. abstract def sum: A

    [use case] Sums up the elements of this collection.

    [use case]

    Sums up the elements of this collection.

    returns

    the sum of all elements in this general sequence of numbers of type Int. Instead of Int, any other type T with an implicit Numeric[T] implementation can be used as element type of the general sequence and as result type of sum. Examples of such types are: Long, Float, Double, BigInt.

    Definition Classes
    GenTraversableOnce
    Full Signature

    abstract def sum[A1 >: A](implicit num: Numeric[A1]): A1

  47. abstract def to[Col[_]]: Col[A]

    [use case] Converts this general sequence into another by copying all elements.

    [use case]

    Converts this general sequence into another by copying all elements.

    Note: will not terminate for infinite-sized collections.

    Col

    The collection type to build.

    returns

    a new collection containing all elements of this general sequence.

    Definition Classes
    GenTraversableOnce
    Full Signature

    abstract def to[Col[_]](implicit cbf: CanBuildFrom[Nothing, A, Col[A]]): Col[A]

  48. abstract def toArray: Array[A]

    [use case] Converts this general sequence to an array.

    [use case]

    Converts this general sequence to an array.

    Note: will not terminate for infinite-sized collections.

    returns

    an array containing all elements of this general sequence. An ClassTag must be available for the element type of this general sequence.

    Definition Classes
    GenTraversableOnce
    Full Signature

    abstract def toArray[A1 >: A](implicit arg0: ClassTag[A1]): Array[A1]

  49. abstract def toMap[T, U]: Map[T, U]

    [use case] Converts this general sequence to a map.

    [use case]

    Converts this general sequence to a map. This method is unavailable unless the elements are members of Tuple2, each ((T, U)) becoming a key-value pair in the map. Duplicate keys will be overwritten by later keys: if this is an unordered collection, which key is in the resulting map is undefined.

    Note: will not terminate for infinite-sized collections.

    returns

    a map of type immutable.Map[T, U] containing all key/value pairs of type (T, U) of this general sequence.

    Definition Classes
    GenTraversableOnce
    Full Signature

    abstract def toMap[K, V](implicit ev: <:<[A, (K, V)]): GenMap[K, V]

  50. def toParArray: ParArray[T]
    Implicit
    This member is added by an implicit conversion from GenSeqLike[A, Repr] to CollectionsHaveToParArray[GenSeqLike[A, Repr], T] performed by method CollectionsHaveToParArray in scala.collection.parallel. This conversion will take place only if an implicit value of type (GenSeqLike[A, Repr]) ⇒ GenTraversableOnce[T] is in scope.
    Definition Classes
    CollectionsHaveToParArray
  51. def toString(): String

    Returns a string representation of the object.

    Returns a string representation of the object.

    The default representation is platform dependent.

    returns

    a string representation of the object.

    Definition Classes
    Any
  52. def union(that: GenSeq[A]): GenSeq[A]

    [use case] Produces a new sequence which contains all elements of this general sequence and also all elements of a given sequence.

    [use case]

    Produces a new sequence which contains all elements of this general sequence and also all elements of a given sequence. xs union ys is equivalent to xs ++ ys.

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

    Note: will not terminate for infinite-sized collections.

    that

    the sequence to add.

    returns

    a new general sequence which contains all elements of this general sequence followed by all elements of that.

    Full Signature

    def union[B >: A, That](that: GenSeq[B])(implicit bf: CanBuildFrom[Repr, B, That]): That

  53. abstract def updated(index: Int, elem: A): GenSeq[A]

    [use case] A copy of this general sequence with one single replaced element.

    [use case]

    A copy of this general sequence with one single replaced element.

    index

    the position of the replacement

    elem

    the replacing element

    returns

    a copy of this general sequence with the element at position index replaced by elem.

    Full Signature

    abstract def updated[B >: A, That](index: Int, elem: B)(implicit bf: CanBuildFrom[Repr, B, That]): That

  54. abstract def zip[B](that: GenIterable[B]): GenSeq[(A, B)]

    [use case] Returns a general sequence formed from this general sequence and another iterable collection by combining corresponding elements in pairs.

    [use case]

    Returns a general sequence formed from this general sequence and another iterable collection by combining corresponding elements in pairs. If one of the two collections is longer than the other, its remaining elements are ignored.

    Note: might return different results for different runs, unless the underlying collection type is ordered.

    B

    the type of the second half of the returned pairs

    that

    The iterable providing the second half of each result pair

    returns

    a new general sequence containing pairs consisting of corresponding elements of this general sequence and that. The length of the returned collection is the minimum of the lengths of this general sequence and that.

    Definition Classes
    GenIterableLike
    Full Signature

    abstract def zip[A1 >: A, B, That](that: GenIterable[B])(implicit bf: CanBuildFrom[Repr, (A1, B), That]): That

  55. abstract def zipAll[B](that: Iterable[B], thisElem: A, thatElem: B): GenSeq[(A, B)]

    [use case] Returns a general sequence formed from this general sequence and another iterable collection by combining corresponding elements in pairs.

    [use case]

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

    Note: might return different results for different runs, unless the underlying collection type is ordered.

    B

    the type of the second half of the returned pairs

    that

    The iterable providing the second half of each result pair

    thisElem

    the element to be used to fill up the result if this general sequence is shorter than that.

    thatElem

    the element to be used to fill up the result if that is shorter than this general sequence.

    returns

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

    Definition Classes
    GenIterableLike
    Full Signature

    abstract def zipAll[B, A1 >: A, That](that: GenIterable[B], thisElem: A1, thatElem: B)(implicit bf: CanBuildFrom[Repr, (A1, B), That]): That

  56. abstract def zipWithIndex: GenSeq[(A, Int)]

    [use case] Zips this general sequence with its indices.

    [use case]

    Zips this general sequence with its indices.

    Note: might return different results for different runs, unless the underlying collection type is ordered.

    returns

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

    Definition Classes
    GenIterableLike
    Full Signature

    abstract def zipWithIndex[A1 >: A, That](implicit bf: CanBuildFrom[Repr, (A1, Int), That]): That

    Example:
    1. List("a", "b", "c").zipWithIndex = List(("a", 0), ("b", 1), ("c", 2))

  57. def [B](y: B): (GenSeqLike[A, Repr], B)
    Implicit
    This member is added by an implicit conversion from GenSeqLike[A, Repr] to ArrowAssoc[GenSeqLike[A, Repr]] performed by method ArrowAssoc in scala.Predef.
    Definition Classes
    ArrowAssoc

Inherited from Equals

Inherited from GenIterableLike[A, Repr]

Inherited from GenTraversableLike[A, Repr]

Inherited from Parallelizable[A, ParSeq[A]]

Inherited from GenTraversableOnce[A]

Inherited from Any

Inherited by implicit conversion CollectionsHaveToParArray from GenSeqLike[A, Repr] to CollectionsHaveToParArray[GenSeqLike[A, Repr], T]

Inherited by implicit conversion any2stringadd from GenSeqLike[A, Repr] to any2stringadd[GenSeqLike[A, Repr]]

Inherited by implicit conversion StringFormat from GenSeqLike[A, Repr] to StringFormat[GenSeqLike[A, Repr]]

Inherited by implicit conversion Ensuring from GenSeqLike[A, Repr] to Ensuring[GenSeqLike[A, Repr]]

Inherited by implicit conversion ArrowAssoc from GenSeqLike[A, Repr] to ArrowAssoc[GenSeqLike[A, Repr]]

Ungrouped