scala.collection.Iterator

# GroupedIterator

#### class GroupedIterator[B >: A] extends Iterator[Seq[B]]

A flexible iterator for transforming an `Iterator[A]` into an Iterator[Seq[A]], with configurable sequence size, step, and strategy for dealing with elements which don't fit evenly.

Typical uses can be achieved via methods `grouped` and `sliding`.

Source
  Iterator.scala

Linear Supertypes
Iterator[Seq[B]], TraversableOnce[Seq[B]], GenTraversableOnce[Seq[B]], AnyRef, Any
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1. GroupedIterator
2. Iterator
3. TraversableOnce
4. GenTraversableOnce
5. AnyRef
6. Any

Visibility

1. Public
2. All

### Instance Constructors

1. #### new GroupedIterator(self: Iterator[A], size: Int, step: Int)

### Type Members

1. #### class GroupedIterator[B >: A] extends Iterator[Seq[B]]

   A flexible iterator for transforming an `Iterator[A]` into an Iterator[Seq[A]], with configurable sequence size, step, and strategy for dealing with elements which don't fit evenly.

### Value Members

1. #### final def !=(arg0: AnyRef): Boolean

   Definition Classes
     AnyRef

2. #### 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

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

   Equivalent to `x.hashCode` except for boxed numeric types.

   Equivalent to `x.hashCode` except for boxed numeric types. 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.

   returns

     a hash value consistent with ==

   Definition Classes
     AnyRef → Any

4. #### abstract def ++(that: ⇒ Iterator[Seq[B]]): Iterator[Seq[B]]

   [use case] Concatenates this iterator with another.

   [use case]

   Concatenates this iterator with another.

   that

     the other iterator

   returns

     a new iterator that first yields the values produced by this iterator followed by the values produced by iterator `that`.

   Definition Classes
     Iterator

5. #### def ++[B >: Seq[B]](that: ⇒ GenTraversableOnce[B]): Iterator[B]

   Concatenates this iterator with another.

   Concatenates this iterator with another.

   that

     the other iterator

   returns

     a new iterator that first yields the values produced by this iterator followed by the values produced by iterator `that`.

   Definition Classes
     Iterator
   Note

     Reuse: After calling this method, one should discard the iterator it was called on, as well as the one passed as a parameter, and use only the iterator that was returned. Using the old iterators is undefined, subject to change, and may result in changes to the new iterator as well.

6. #### def /:[B](z: B)(op: (B, Seq[B]) ⇒ B): B

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

   Applies a binary operator to a start value and all elements of this traversable 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 = LinkedList(1,2,3,4)
            a: scala.collection.mutable.LinkedList[Int] = LinkedList(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 iterators.

   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 traversable or iterator, going left to right with the start value `z` on the left:

                     op(...op(op(z, x1), x2), ..., xn)

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

   Definition Classes
     TraversableOnce → GenTraversableOnce

7. #### def /:\[A1 >: Seq[B]](z: A1)(op: (A1, A1) ⇒ A1): A1

   A syntactic sugar for out of order folding.

   A syntactic sugar for out of order folding. See `fold`.

   Example:

            scala> val a = LinkedList(1,2,3,4)
            a: scala.collection.mutable.LinkedList[Int] = LinkedList(1, 2, 3, 4)

            scala> val b = (a /:\ 5)(_+_)
            b: Int = 15

   Definition Classes
     GenTraversableOnce

8. #### def :\[B](z: B)(op: (Seq[B], B) ⇒ B): B

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

   Applies a binary operator to all elements of this traversable 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 iterators.

   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 = LinkedList(1,2,3,4)
            a: scala.collection.mutable.LinkedList[Int] = LinkedList(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 traversable or iterator, going right to left with the start value `z` on the right:

                     op(x1, op(x2, ... op(xn, z)...))

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

   Definition Classes
     TraversableOnce → GenTraversableOnce

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

   Definition Classes
     AnyRef

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

    Test two objects for equality.

    Test two objects for equality.

    returns

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

    Definition Classes
      Any

11. #### def addString(b: StringBuilder): StringBuilder

    Appends all elements of this traversable or iterator to a string builder.

    Appends all elements of this traversable or iterator to a string builder. The written text consists of the string representations (w.r.t. the method `toString`) of all elements of this traversable or iterator without any separator string.

    Example:

             scala> val a = LinkedList(1,2,3,4)
             a: scala.collection.mutable.LinkedList[Int] = LinkedList(1, 2, 3, 4)

             scala> val b = new StringBuilder()
             b: StringBuilder =

             scala> val h = a.addString(b)
             b: StringBuilder = 1234

    b

      the string builder to which elements are appended.

    returns

      the string builder `b` to which elements were appended.

    Definition Classes
      TraversableOnce

12. #### def addString(b: StringBuilder, sep: String): StringBuilder

    Appends all elements of this traversable or iterator to a string builder using a separator string.

    Appends all elements of this traversable or iterator to a string builder using a separator string. The written text consists of the string representations (w.r.t. the method `toString`) of all elements of this traversable or iterator, separated by the string `sep`.

    Example:

             scala> val a = LinkedList(1,2,3,4)
             a: scala.collection.mutable.LinkedList[Int] = LinkedList(1, 2, 3, 4)

             scala> val b = new StringBuilder()
             b: StringBuilder =

             scala> a.addString(b, ", ")
             res0: StringBuilder = 1, 2, 3, 4

    b

      the string builder to which elements are appended.

    sep

      the separator string.

    returns

      the string builder `b` to which elements were appended.

    Definition Classes
      TraversableOnce

13. #### def addString(b: StringBuilder, start: String, sep: String, end: String): StringBuilder

    Appends all elements of this traversable or iterator to a string builder using start, end, and separator strings.

    Appends all elements of this traversable or iterator to a string builder using start, end, and separator strings. The written text 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 traversable or iterator are separated by the string `sep`.

    Example:

             scala> val a = LinkedList(1,2,3,4)
             a: scala.collection.mutable.LinkedList[Int] = LinkedList(1, 2, 3, 4)

             scala> val b = new StringBuilder()
             b: StringBuilder =

             scala> a.addString(b, "LinkedList(", ", ", ")")
             res1: StringBuilder = LinkedList(1, 2, 3, 4)

    b

      the string builder to which elements are appended.

    start

      the starting string.

    sep

      the separator string.

    end

      the ending string.

    returns

      the string builder `b` to which elements were appended.

    Definition Classes
      TraversableOnce

14. #### def aggregate[B](z: B)(seqop: (B, Seq[B]) ⇒ 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 has similar semantics, but does not require the result to be a supertype of the element type. It traverses the elements in different partitions sequentially, using `seqop` to update the result, and then applies `combop` to results from different partitions. The implementation of this operation may operate on an arbitrary number of collection partitions, so `combop` may be invoked an arbitrary number of times.

    For example, one might want to process some elements and then produce a `Set`. In this case, `seqop` would process an element and append it to the list, while `combop` would concatenate two lists from different partitions together. The initial value `z` would be an empty set.

           pc.aggregate(Set[Int]())(_ += process(_), _ ++ _)

    Another example is calculating geometric mean from a collection of doubles (one would typically require big doubles for this).

    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)

    seqop

      an operator used to accumulate results within a partition

    combop

      an associative operator used to combine results from different partitions

    Definition Classes
      TraversableOnce → GenTraversableOnce

15. #### 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`.

16. #### def buffered: BufferedIterator[Seq[B]]

    Creates a buffered iterator from this iterator.

    Creates a buffered iterator from this iterator.

    returns

      a buffered iterator producing the same values as this iterator.

    Definition Classes
      Iterator
    Note

      Reuse: After calling this method, one should discard the iterator it was called on, and use only the iterator that was returned. Using the old iterator is undefined, subject to change, and may result in changes to the new iterator as well.

    See also

      BufferedIterator

17. #### def clone(): AnyRef

    Create a copy of the receiver object.

    Create a copy of the receiver object.

    The default implementation of the `clone` method is platform dependent.

    returns

      a copy of the receiver object.

    Attributes
      protected[lang]
    Definition Classes
      AnyRef
    Annotations
      @throws()
    Note

      not specified by SLS as a member of AnyRef

18. #### def collect[B](pf: PartialFunction[Seq[B], B]): Iterator[B]

    Creates an iterator by transforming values produced by this iterator with a partial function, dropping those values for which the partial function is not defined.

    Creates an iterator by transforming values produced by this iterator with a partial function, dropping those values for which the partial function is not defined.

    pf

      the partial function which filters and maps the iterator.

    returns

      a new iterator which yields each value `x` produced by this iterator for which `pf` is defined the image `pf(x)`.

    Definition Classes
      Iterator
    Annotations
      @migration
    Migration

      (Changed in version 2.8.0) `collect` has changed. The previous behavior can be reproduced with `toSeq`.

    Note

      Reuse: After calling this method, one should discard the iterator it was called on, and use only the iterator that was returned. Using the old iterator is undefined, subject to change, and may result in changes to the new iterator as well.

19. #### def collectFirst[B](pf: PartialFunction[Seq[B], B]): Option[B]

    Finds the first element of the traversable or iterator for which the given partial function is defined, and applies the partial function to it.

    Finds the first element of the traversable or iterator for which the given partial function is defined, and applies the partial function to it.

    Note: may not terminate for infinite iterators.

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

    pf

      the partial function

    returns

      an option value containing pf applied to the first value for which it is defined, or `None` if none exists.

    Definition Classes
      TraversableOnce
    Example:

    1. `Seq("a", 1, 5L).collectFirst({ case x: Int => x*10 }) = Some(10)`

20. #### def contains(elem: Any): Boolean

    Tests whether this iterator contains a given value as an element.

    Tests whether this iterator contains a given value as an element.

    Note: may not terminate for infinite iterators.

    elem

      the element to test.

    returns

      `true` if this iterator produces some value that is is equal (wrt `==`) to `elem`, `false` otherwise.

    Definition Classes
      Iterator
    Note

      Reuse: After calling this method, one should discard the iterator it was called on. Using it is undefined and subject to change.

21. #### abstract def copyToArray(xs: Array[Seq[B]], start: Int, len: Int): Unit

    [use case] Copies selected values produced by this iterator to an array.

    [use case]

    Copies selected values produced by this iterator to an array. Fills the given array `xs` starting at index `start` with at most `len` values produced by this iterator. Copying will stop once either the end of the current iterator is reached, or the end of the array is reached, or `len` elements have been copied.

    xs

      the array to fill.

    start

      the starting index.

    len

      the maximal number of elements to copy.

    Definition Classes
      Iterator

22. #### def copyToArray[B >: Seq[B]](xs: Array[B], start: Int, len: Int): Unit

    Copies selected values produced by this iterator to an array.

    Copies selected values produced by this iterator to an array. Fills the given array `xs` starting at index `start` with at most `len` values produced by this iterator. Copying will stop once either the end of the current iterator is reached, or the end of the array is reached, or `len` elements have been copied.

    Note: will not terminate for infinite iterators.

    B

      the type of the elements of the array.

    xs

      the array to fill.

    start

      the starting index.

    len

      the maximal number of elements to copy.

    Definition Classes
      Iterator → TraversableOnce → GenTraversableOnce
    Note

      Reuse: After calling this method, one should discard the iterator it was called on. Using it is undefined and subject to change.

23. #### abstract def copyToArray(xs: Array[Seq[B]]): Unit

    [use case] Copies values of this traversable or iterator to an array.

    [use case]

    Copies values of this traversable or iterator to an array. Fills the given array `xs` with values of this traversable or iterator. Copying will stop once either the end of the current traversable or iterator is reached, or the end of the array is reached.

    xs

      the array to fill.

    Definition Classes
      GenTraversableOnce

24. #### def copyToArray[B >: Seq[B]](xs: Array[B]): Unit

    Copies values of this traversable or iterator to an array.

    Copies values of this traversable or iterator to an array. Fills the given array `xs` with values of this traversable or iterator. Copying will stop once either the end of the current traversable or iterator is reached, or the end of the array is reached.

    Note: will not terminate for infinite iterators.

    B

      the type of the elements of the array.

    xs

      the array to fill.

    Definition Classes
      TraversableOnce → GenTraversableOnce

25. #### abstract def copyToArray(xs: Array[Seq[B]], start: Int): Unit

    [use case] Copies values of this traversable or iterator to an array.

    [use case]

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

    xs

      the array to fill.

    start

      the starting index.

    Definition Classes
      GenTraversableOnce

26. #### def copyToArray[B >: Seq[B]](xs: Array[B], start: Int): Unit

    Copies values of this traversable or iterator to an array.

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

    Note: will not terminate for infinite iterators.

    B

      the type of the elements of the array.

    xs

      the array to fill.

    start

      the starting index.

    Definition Classes
      TraversableOnce → GenTraversableOnce

27. #### def copyToBuffer[B >: Seq[B]](dest: Buffer[B]): Unit

    Copies all elements of this traversable or iterator to a buffer.

    Copies all elements of this traversable or iterator to a buffer.

    Note: will not terminate for infinite iterators.

    dest

      The buffer to which elements are copied.

    Definition Classes
      TraversableOnce

28. #### def count(p: (Seq[B]) ⇒ Boolean): Int

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

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

    p

      the predicate used to test elements.

    returns

      the number of elements satisfying the predicate `p`.

    Definition Classes
      TraversableOnce → GenTraversableOnce

29. #### def drop(n: Int): Iterator[Seq[B]]

    Advances this iterator past the first n elements, or the length of the iterator, whichever is smaller.

    Advances this iterator past the first n elements, or the length of the iterator, whichever is smaller.

    n

      the number of elements to drop

    returns

      an iterator which produces all values of the current iterator, except it omits the first `n` values.

    Definition Classes
      Iterator
    Note

      Reuse: After calling this method, one should discard the iterator it was called on, and use only the iterator that was returned. Using the old iterator is undefined, subject to change, and may result in changes to the new iterator as well.

30. #### def dropWhile(p: (Seq[B]) ⇒ Boolean): Iterator[Seq[B]]

    Skips longest sequence of elements of this iterator which satisfy given predicate `p`, and returns an iterator of the remaining elements.

    Skips longest sequence of elements of this iterator which satisfy given predicate `p`, and returns an iterator of the remaining elements.

    p

      the predicate used to skip elements.

    returns

      an iterator consisting of the remaining elements

    Definition Classes
      Iterator
    Note

      Reuse: After calling this method, one should discard the iterator it was called on, and use only the iterator that was returned. Using the old iterator is undefined, subject to change, and may result in changes to the new iterator as well.

31. #### def duplicate: (Iterator[Seq[B]], Iterator[Seq[B]])

    Creates two new iterators that both iterate over the same elements as this iterator (in the same order).

    Creates two new iterators that both iterate over the same elements as this iterator (in the same order). The duplicate iterators are considered equal if they are positioned at the same element.

    Given that most methods on iterators will make the original iterator unfit for further use, this methods provides a reliable way of calling multiple such methods on an iterator.

    returns

      a pair of iterators

    Definition Classes
      Iterator
    Note

      Reuse: After calling this method, one should discard the iterator it was called on, and use only the iterators that were returned. Using the old iterator is undefined, subject to change, and may result in changes to the new iterators as well.

      ,

      The implementation may allocate temporary storage for elements iterated by one iterator but not yet by the other.

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

    Tests whether the argument (`arg0`) is a reference to the receiver object (`this`).

    Tests whether the argument (`arg0`) is a reference to the receiver object (`this`).

    The `eq` method implements an equivalence relation on non-null instances of `AnyRef`, and has three additional properties:

    - It is consistent: for any non-null instances `x` and `y` of type `AnyRef`, multiple invocations of `x.eq(y)` consistently returns `true` or consistently returns `false`.
    - For any non-null instance `x` of type `AnyRef`, `x.eq(null)` and `null.eq(x)` returns `false`.
    - `null.eq(null)` returns `true`.

    When overriding the `equals` or `hashCode` methods, it is important to ensure that their behavior is consistent with reference equality. Therefore, if two objects are references to each other (`o1 eq o2`), they should be equal to each other (`o1 == o2`) and they should hash to the same value (`o1.hashCode == o2.hashCode`).

    returns

      `true` if the argument is a reference to the receiver object; `false` otherwise.

    Definition Classes
      AnyRef

33. #### def equals(arg0: Any): Boolean

    The equality method for reference types.

    The equality method for reference types. See equals in Any.

    returns

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

    Definition Classes
      AnyRef → Any

34. #### def exists(p: (Seq[B]) ⇒ Boolean): Boolean

    Tests whether a predicate holds for some of the values produced by this iterator.

    Tests whether a predicate holds for some of the values produced by this iterator.

    Note: may not terminate for infinite iterators.

    p

      the predicate used to test elements.

    returns

      `true` if the given predicate `p` holds for some of the values produced by this iterator, otherwise `false`.

    Definition Classes
      Iterator → TraversableOnce → GenTraversableOnce
    Note

      Reuse: After calling this method, one should discard the iterator it was called on. Using it is undefined and subject to change.

35. #### def filter(p: (Seq[B]) ⇒ Boolean): Iterator[Seq[B]]

    Returns an iterator over all the elements of this iterator that satisfy the predicate `p`.

    Returns an iterator over all the elements of this iterator that satisfy the predicate `p`. The order of the elements is preserved.

    p

      the predicate used to test values.

    returns

      an iterator which produces those values of this iterator which satisfy the predicate `p`.

    Definition Classes
      Iterator
    Note

      Reuse: After calling this method, one should discard the iterator it was called on, and use only the iterator that was returned. Using the old iterator is undefined, subject to change, and may result in changes to the new iterator as well.

36. #### def filterNot(p: (Seq[B]) ⇒ Boolean): Iterator[Seq[B]]

    Creates an iterator over all the elements of this iterator which do not satisfy a predicate p.

    Creates an iterator over all the elements of this iterator which do not satisfy a predicate p.

    p

      the predicate used to test values.

    returns

      an iterator which produces those values of this iterator which do not satisfy the predicate `p`.

    Definition Classes
      Iterator
    Note

      Reuse: After calling this method, one should discard the iterator it was called on, and use only the iterator that was returned. Using the old iterator is undefined, subject to change, and may result in changes to the new iterator as well.

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

    Called by the garbage collector on the receiver object when there are no more references to the object.

    Called by the garbage collector on the receiver object when there are no more references to the object.

    The details of when and if the `finalize` method is invoked, as well as the interaction between `finalize` and non-local returns and exceptions, are all platform dependent.

    Attributes
      protected[lang]
    Definition Classes
      AnyRef
    Annotations
      @throws()
    Note

      not specified by SLS as a member of AnyRef

38. #### def find(p: (Seq[B]) ⇒ Boolean): Option[Seq[B]]

    Finds the first value produced by the iterator satisfying a predicate, if any.

    Finds the first value produced by the iterator satisfying a predicate, if any.

    Note: may not terminate for infinite iterators.

    p

      the predicate used to test values.

    returns

      an option value containing the first value produced by the iterator that satisfies predicate `p`, or `None` if none exists.

    Definition Classes
      Iterator → TraversableOnce → GenTraversableOnce
    Note

      Reuse: After calling this method, one should discard the iterator it was called on. Using it is undefined and subject to change.

39. #### def flatMap[B](f: (Seq[B]) ⇒ GenTraversableOnce[B]): Iterator[B]

    Creates a new iterator by applying a function to all values produced by this iterator and concatenating the results.

    Creates a new iterator by applying a function to all values produced by this iterator and concatenating the results.

    f

      the function to apply on each element.

    returns

      the iterator resulting from applying the given iterator-valued function `f` to each value produced by this iterator and concatenating the results.

    Definition Classes
      Iterator
    Note

      Reuse: After calling this method, one should discard the iterator it was called on, and use only the iterator that was returned. Using the old iterator is undefined, subject to change, and may result in changes to the new iterator as well.

40. #### def fold[A1 >: Seq[B]](z: A1)(op: (A1, A1) ⇒ A1): A1

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

    Folds the elements of this traversable 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`.

    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 fold operator `op` between all the elements and `z`

    Definition Classes
      TraversableOnce → GenTraversableOnce

41. #### def foldLeft[B](z: B)(op: (B, Seq[B]) ⇒ B): B

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

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

    Note: will not terminate for infinite iterators.

    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 traversable or iterator, going left to right with the start value `z` on the left:

                      op(...op(z, x1), x2, ..., xn)

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

    Definition Classes
      TraversableOnce → GenTraversableOnce

42. #### def foldRight[B](z: B)(op: (Seq[B], B) ⇒ B): B

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

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

    Note: will not terminate for infinite iterators.

    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 traversable or iterator, going right to left with the start value `z` on the right:

                      op(x1, op(x2, ... op(xn, z)...))

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

    Definition Classes
      TraversableOnce → GenTraversableOnce

43. #### def forall(p: (Seq[B]) ⇒ Boolean): Boolean

    Tests whether a predicate holds for all values produced by this iterator.

    Tests whether a predicate holds for all values produced by this iterator.

    Note: may not terminate for infinite iterators.

    p

      the predicate used to test elements.

    returns

      `true` if the given predicate `p` holds for all values produced by this iterator, otherwise `false`.

    Definition Classes
      Iterator → TraversableOnce → GenTraversableOnce
    Note

      Reuse: After calling this method, one should discard the iterator it was called on. Using it is undefined and subject to change.

44. #### abstract def foreach(f: (Seq[B]) ⇒ Unit): Unit

    [use case] Applies a function `f` to all values produced by this iterator.

    [use case]

    Applies a function `f` to all values produced by this iterator.

    f

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

    Definition Classes
      Iterator

45. #### def foreach[U](f: (Seq[B]) ⇒ U): Unit

    Applies a function `f` to all values produced by this iterator.

    Applies a function `f` to all values produced by this iterator.

    U

      the type parameter describing the result of function `f`. This result will always be ignored. Typically `U` is `Unit`, but this is not necessary.

    f

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

    Definition Classes
      Iterator → TraversableOnce → GenTraversableOnce
    Note

      Reuse: After calling this method, one should discard the iterator it was called on. Using it is undefined and subject to change.

46. #### final def getClass(): java.lang.Class[_]

    A representation that corresponds to the dynamic class of the receiver object.

    A representation that corresponds to the dynamic class of the receiver object.

    The nature of the representation is platform dependent.

    returns

      a representation that corresponds to the dynamic class of the receiver object.

    Definition Classes
      AnyRef → Any
    Note

      not specified by SLS as a member of AnyRef

47. #### def grouped[B >: Seq[B]](size: Int): GroupedIterator[B]

    Returns an iterator which groups this iterator into fixed size blocks.

    Returns an iterator which groups this iterator into fixed size blocks. Example usages:

           // Returns List(List(1, 2, 3), List(4, 5, 6), List(7)))
           (1 to 7).iterator grouped 3 toList
           // Returns List(List(1, 2, 3), List(4, 5, 6))
           (1 to 7).iterator grouped 3 withPartial false toList
           // Returns List(List(1, 2, 3), List(4, 5, 6), List(7, 20, 25)
           // Illustrating that withPadding's argument is by-name.
           val it2 = Iterator.iterate(20)(_ + 5)
           (1 to 7).iterator grouped 3 withPadding it2.next toList

    Definition Classes
      Iterator
    Note

      Reuse: After calling this method, one should discard the iterator it was called on, and use only the iterator that was returned. Using the old iterator is undefined, subject to change, and may result in changes to the new iterator as well.

48. #### def hasDefiniteSize: Boolean

    Tests whether this Iterator has a known size.

    Tests whether this Iterator has a known size.

    returns

      `true` for empty Iterators, `false` otherwise.

    Definition Classes
      Iterator → TraversableOnce → GenTraversableOnce
    Note

      Reuse: The iterator remains valid for further use whatever result is returned.

49. #### def hasNext: Boolean

    Tests whether this iterator can provide another element.

    Tests whether this iterator can provide another element.

    returns

      `true` if a subsequent call to `next` will yield an element, `false` otherwise.

    Definition Classes
      GroupedIterator → Iterator
    Note

      Reuse: The iterator remains valid for further use whatever result is returned.

50. #### def hashCode(): Int

    The hashCode method for reference types.

    The hashCode method for reference types. See hashCode in Any.

    returns

      the hash code value for this object.

    Definition Classes
      AnyRef → Any

51. #### def indexOf[B >: Seq[B]](elem: B): Int

    Returns the index of the first occurrence of the specified object in this iterable object.

    Returns the index of the first occurrence of the specified object in this iterable object.

    Note: may not terminate for infinite iterators.

    elem

      element to search for.

    returns

      the index of the first occurrence of `elem` in the values produced by this iterator, or -1 if such an element does not exist until the end of the iterator is reached.

    Definition Classes
      Iterator
    Note

      Reuse: After calling this method, one should discard the iterator it was called on. Using it is undefined and subject to change.

52. #### def indexWhere(p: (Seq[B]) ⇒ Boolean): Int

    Returns the index of the first produced value satisfying a predicate, or -1.

    Returns the index of the first produced value satisfying a predicate, or -1.

    Note: may not terminate for infinite iterators.

    p

      the predicate to test values

    returns

      the index of the first produced value satisfying `p`, or -1 if such an element does not exist until the end of the iterator is reached.

    Definition Classes
      Iterator
    Note

      Reuse: After calling this method, one should discard the iterator it was called on. Using it is undefined and subject to change.

53. #### def isEmpty: Boolean

    Tests whether this iterator is empty.

    Tests whether this iterator is empty.

    returns

      `true` if hasNext is false, `false` otherwise.

    Definition Classes
      Iterator → TraversableOnce → GenTraversableOnce
    Note

      Reuse: The iterator remains valid for further use whatever result is returned.

54. #### 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

55. #### def isTraversableAgain: Boolean

    Tests whether this Iterator can be repeatedly traversed.

    Tests whether this Iterator can be repeatedly traversed.

    returns

      `false`

    Definition Classes
      Iterator → GenTraversableOnce
    Note

      Reuse: The iterator remains valid for further use whatever result is returned.

56. #### def length: Int

    Returns the number of elements in this iterator.

    Returns the number of elements in this iterator.

    Note: will not terminate for infinite iterators.

    Definition Classes
      Iterator
    Note

      Reuse: After calling this method, one should discard the iterator it was called on. Using it is undefined and subject to change.

57. #### def map[B](f: (Seq[B]) ⇒ B): Iterator[B]

    Creates a new iterator that maps all produced values of this iterator to new values using a transformation function.

    Creates a new iterator that maps all produced values of this iterator to new values using a transformation function.

    f

      the transformation function

    returns

      a new iterator which transforms every value produced by this iterator by applying the function `f` to it.

    Definition Classes
      Iterator
    Note

      Reuse: After calling this method, one should discard the iterator it was called on, and use only the iterator that was returned. Using the old iterator is undefined, subject to change, and may result in changes to the new iterator as well.

58. #### abstract def max: Seq[B]

    [use case] Finds the largest element.

    [use case]

    Finds the largest element.

    returns

      the largest element of this traversable or iterator with respect to the ordering `cmp`.

    Definition Classes
      GenTraversableOnce

59. #### def max[B >: Seq[B]](implicit cmp: Ordering[B]): Seq[B]

    Finds the largest element.

    Finds the largest element.

    B

      The type over which the ordering is defined.

    cmp

      An ordering to be used for comparing elements.

    returns

      the largest element of this traversable or iterator with respect to the ordering `cmp`.

    Definition Classes
      TraversableOnce → GenTraversableOnce

60. #### def maxBy[B](f: (Seq[B]) ⇒ B)(implicit cmp: Ordering[B]): Seq[B]

    Definition Classes
      TraversableOnce → GenTraversableOnce

61. #### abstract def min: Seq[B]

    [use case] Finds the smallest element.

    [use case]

    Finds the smallest element.

    returns

      the smallest element of this traversable or iterator with respect to the ordering `cmp`.

    Definition Classes
      GenTraversableOnce

62. #### def min[B >: Seq[B]](implicit cmp: Ordering[B]): Seq[B]

    Finds the smallest element.

    Finds the smallest element.

    B

      The type over which the ordering is defined.

    cmp

      An ordering to be used for comparing elements.

    returns

      the smallest element of this traversable or iterator with respect to the ordering `cmp`.

    Definition Classes
      TraversableOnce → GenTraversableOnce

63. #### def minBy[B](f: (Seq[B]) ⇒ B)(implicit cmp: Ordering[B]): Seq[B]

    Definition Classes
      TraversableOnce → GenTraversableOnce

64. #### def mkString: String

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

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

    returns

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

    Definition Classes
      TraversableOnce → GenTraversableOnce

65. #### def mkString(sep: String): String

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

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

    sep

      the separator string.

    returns

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

    Definition Classes
      TraversableOnce → GenTraversableOnce
    Example:

    1. `List(1, 2, 3).mkString("|") = "1|2|3"`

66. #### def mkString(start: String, sep: String, end: String): String

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

    Displays all elements of this traversable 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 traversable 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 traversable or iterator are separated by the string `sep`.

    Definition Classes
      TraversableOnce → GenTraversableOnce
    Example:

    1. `List(1, 2, 3).mkString("(", "; ", ")") = "(1; 2; 3)"`

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

    Equivalent to `!(this eq that)`.

    Equivalent to `!(this eq that)`.

    returns

      `true` if the argument is not a reference to the receiver object; `false` otherwise.

    Definition Classes
      AnyRef

68. #### def next(): List[B]

    Produces the next element of this iterator.

    Produces the next element of this iterator.

    returns

      the next element of this iterator, if `hasNext` is `true`, undefined behavior otherwise.

    Definition Classes
      GroupedIterator → Iterator
    Note

      Reuse: The iterator remains valid for further use whatever result is returned.

69. #### def nonEmpty: Boolean

    Tests whether the traversable or iterator is not empty.

    Tests whether the traversable or iterator is not empty.

    returns

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

    Definition Classes
      TraversableOnce → GenTraversableOnce

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

    Wakes up a single thread that is waiting on the receiver object's monitor.

    Wakes up a single thread that is waiting on the receiver object's monitor.

    Definition Classes
      AnyRef
    Note

      not specified by SLS as a member of AnyRef

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

    Wakes up all threads that are waiting on the receiver object's monitor.

    Wakes up all threads that are waiting on the receiver object's monitor.

    Definition Classes
      AnyRef
    Note

      not specified by SLS as a member of AnyRef

72. #### abstract def padTo(len: Int, elem: Seq[B]): Iterator[Seq[B]]

    [use case] Appends an element value to this iterator until a given target length is reached.

    [use case]

    Appends an element value to this iterator until a given target length is reached.

    len

      the target length

    elem

      the padding value

    returns

      a new iterator consisting of producing all values of this iterator, followed by the minimal number of occurrences of `elem` so that the number of produced values is at least `len`.

    Definition Classes
      Iterator

73. #### def padTo[A1 >: Seq[B]](len: Int, elem: A1): Iterator[A1]

    Appends an element value to this iterator until a given target length is reached.

    Appends an element value to this iterator until a given target length is reached.

    len

      the target length

    elem

      the padding value

    returns

      a new iterator consisting of producing all values of this iterator, followed by the minimal number of occurrences of `elem` so that the number of produced values is at least `len`.

    Definition Classes
      Iterator
    Note

      Reuse: After calling this method, one should discard the iterator it was called on, and use only the iterator that was returned. Using the old iterator is undefined, subject to change, and may result in changes to the new iterator as well.

74. #### def partition(p: (Seq[B]) ⇒ Boolean): (Iterator[Seq[B]], Iterator[Seq[B]])

    Partitions this iterator in two iterators according to a predicate.

    Partitions this iterator in two iterators according to a predicate.

    p

      the predicate on which to partition

    returns

      a pair of iterators: the iterator that satisfies the predicate `p` and the iterator that does not. The relative order of the elements in the resulting iterators is the same as in the original iterator.

    Definition Classes
      Iterator
    Note

      Reuse: After calling this method, one should discard the iterator it was called on, and use only the iterators that were returned. Using the old iterator is undefined, subject to change, and may result in changes to the new iterators as well.

75. #### def patch[B >: Seq[B]](from: Int, patchElems: Iterator[B], replaced: Int): Iterator[B]

    Returns this iterator with patched values.

    Returns this iterator with patched values.

    from

      The start index from which to patch

    patchElems

      The iterator of patch values

    replaced

      The number of values in the original iterator that are replaced by the patch.

    Definition Classes
      Iterator
    Note

      Reuse: After calling this method, one should discard the iterator it was called on, as well as the one passed as a parameter, and use only the iterator that was returned. Using the old iterators is undefined, subject to change, and may result in changes to the new iterator as well.

76. #### abstract def product: Seq[B]

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

    [use case]

    Multiplies up the elements of this collection.

    returns

      the product of all elements of this traversable or iterator with respect to the `*` operator in `num`.

    Definition Classes
      GenTraversableOnce

77. #### def product[B >: Seq[B]](implicit num: Numeric[B]): B

    Multiplies up the elements of this collection.

    Multiplies up the elements of this collection.

    B

      the result type of the `*` operator.

    num

      an implicit parameter defining a set of numeric operations which includes the `*` operator to be used in forming the product.

    returns

      the product of all elements of this traversable or iterator with respect to the `*` operator in `num`.

    Definition Classes
      TraversableOnce → GenTraversableOnce

78. #### def reduce[A1 >: Seq[B]](op: (A1, A1) ⇒ A1): A1

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

    Reduces the elements of this traversable 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 traversable or iterator is nonempty.

    Definition Classes
      TraversableOnce → GenTraversableOnce
    Exceptions thrown
      UnsupportedOperationException

      if this traversable or iterator is empty.

79. #### def reduceLeft[B >: Seq[B]](op: (B, Seq[B]) ⇒ B): B

    Definition Classes
      TraversableOnce

80. #### def reduceLeftOption[B >: Seq[B]](op: (B, Seq[B]) ⇒ B): Option[B]

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

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

    Note: will not terminate for infinite iterators.

    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)` is this traversable or iterator is nonempty, `None` otherwise.

    Definition Classes
      TraversableOnce → GenTraversableOnce

81. #### def reduceOption[A1 >: Seq[B]](op: (A1, A1) ⇒ A1): Option[A1]

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

    Reduces the elements of this traversable 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
      TraversableOnce → GenTraversableOnce

82. #### def reduceRight[B >: Seq[B]](op: (Seq[B], B) ⇒ B): B

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

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

    Note: will not terminate for infinite iterators.

    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 traversable 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 traversable or iterator.

    Definition Classes
      TraversableOnce → GenTraversableOnce
    Exceptions thrown
      `UnsupportedOperationException`

      if this traversable or iterator is empty.

83. #### def reduceRightOption[B >: Seq[B]](op: (Seq[B], B) ⇒ B): Option[B]

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

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

    Note: will not terminate for infinite iterators.

    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)` is this traversable or iterator is nonempty, `None` otherwise.

    Definition Classes
      TraversableOnce → GenTraversableOnce

84. #### def reversed: List[Seq[B]]

    Attributes
      protected[this]
    Definition Classes
      TraversableOnce

85. #### def sameElements(that: Iterator[_]): Boolean

    Tests if another iterator produces the same values as this one.

    Tests if another iterator produces the same values as this one.

    Note: will not terminate for infinite iterators.

    that

      the other iterator

    returns

      `true`, if both iterators produce the same elements in the same order, `false` otherwise.

    Definition Classes
      Iterator
    Note

      Reuse: After calling this method, one should discard the iterator it was called on, as well as the one passed as parameter. Using the old iterators is undefined and subject to change.

86. #### def scanLeft[B](z: B)(op: (B, Seq[B]) ⇒ B): Iterator[B]

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

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

    Note: will not terminate for infinite iterators.

    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

    z

      the initial value

    op

      the binary operator applied to the intermediate result and the element

    returns

      iterator with intermediate results

    Definition Classes
      Iterator
    Note

      Reuse: After calling this method, one should discard the iterator it was called on, and use only the iterator that was returned. Using the old iterator is undefined, subject to change, and may result in changes to the new iterator as well.

87. #### def scanRight[B](z: B)(op: (Seq[B], B) ⇒ B): Iterator[B]

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

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

    Note: will not terminate for infinite iterators.

    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

    z

      the initial value

    op

      the binary operator applied to the intermediate result and the element

    returns

      iterator with intermediate results

    Definition Classes
      Iterator
    Example:

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

    Note

      Reuse: After calling this method, one should discard the iterator it was called on, and use only the iterator that was returned. Using the old iterator is undefined, subject to change, and may result in changes to the new iterator as well.

88. #### def seq: Iterator[Seq[B]]

    A version of this collection with all of the operations implemented sequentially (i.

    A version of this collection with all of the operations implemented sequentially (i.e. in a single-threaded manner).

    This method returns a reference to this collection. In parallel collections, it is redefined to return a sequential implementation of this collection. In both cases, it has O(1) complexity.

    returns

      a sequential view of the collection.

    Definition Classes
      Iterator → TraversableOnce → GenTraversableOnce

89. #### def slice(from: Int, until: Int): Iterator[Seq[B]]

    Creates an iterator returning an interval of the values produced by this iterator.

    Creates an iterator returning an interval of the values produced by this iterator.

    from

      the index of the first element in this iterator which forms part of the slice.

    until

      the index of the first element following the slice.

    returns

      an iterator which advances this iterator past the first `from` elements using `drop`, and then takes `until - from` elements, using `take`.

    Definition Classes
      Iterator
    Note

      Reuse: After calling this method, one should discard the iterator it was called on, and use only the iterator that was returned. Using the old iterator is undefined, subject to change, and may result in changes to the new iterator as well.

90. #### def sliding[B >: Seq[B]](size: Int, step: Int = 1): GroupedIterator[B]

    Returns an iterator which presents a "sliding window" view of another iterator.

    Returns an iterator which presents a "sliding window" view of another iterator. The first argument is the window size, and the second is how far to advance the window on each iteration; defaults to `1`. Example usages:

           // Returns List(List(1, 2, 3), List(2, 3, 4), List(3, 4, 5))
           (1 to 5).iterator.sliding(3).toList
           // Returns List(List(1, 2, 3, 4), List(4, 5))
           (1 to 5).iterator.sliding(4, 3).toList
           // Returns List(List(1, 2, 3, 4))
           (1 to 5).iterator.sliding(4, 3).withPartial(false).toList
           // Returns List(List(1, 2, 3, 4), List(4, 5, 20, 25))
           // Illustrating that withPadding's argument is by-name.
           val it2 = Iterator.iterate(20)(_ + 5)
           (1 to 5).iterator.sliding(4, 3).withPadding(it2.next).toList

    Definition Classes
      Iterator
    Note

      Reuse: After calling this method, one should discard the iterator it was called on, and use only the iterator that was returned. Using the old iterator is undefined, subject to change, and may result in changes to the new iterator as well.

91. #### def span(p: (Seq[B]) ⇒ Boolean): (Iterator[Seq[B]], Iterator[Seq[B]])

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

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

    p

      the test predicate

    returns

      a pair of Iterators consisting of the longest prefix of this whose elements all satisfy `p`, and the rest of the Iterator.

    Definition Classes
      Iterator
    Note

      Reuse: After calling this method, one should discard the iterator it was called on, and use only the iterators that were returned. Using the old iterator is undefined, subject to change, and may result in changes to the new iterators as well.

92. #### abstract def sum: Seq[B]

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

    [use case]

    Sums up the elements of this collection.

    returns

      the sum of all elements of this traversable or iterator with respect to the `+` operator in `num`.

    Definition Classes
      GenTraversableOnce

93. #### def sum[B >: Seq[B]](implicit num: Numeric[B]): B

    Sums up the elements of this collection.

    Sums up the elements of this collection.

    B

      the result type of the `+` operator.

    num

      an implicit parameter defining a set of numeric operations which includes the `+` operator to be used in forming the sum.

    returns

      the sum of all elements of this traversable or iterator with respect to the `+` operator in `num`.

    Definition Classes
      TraversableOnce → GenTraversableOnce

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

    Definition Classes
      AnyRef

95. #### def take(n: Int): Iterator[Seq[B]]

    Selects first n values of this iterator.

    Selects first n values of this iterator.

    n

      the number of values to take

    returns

      an iterator producing only of the first `n` values of this iterator, or else the whole iterator, if it produces fewer than `n` values.

    Definition Classes
      Iterator
    Note

      Reuse: After calling this method, one should discard the iterator it was called on, and use only the iterator that was returned. Using the old iterator is undefined, subject to change, and may result in changes to the new iterator as well.

96. #### def takeWhile(p: (Seq[B]) ⇒ Boolean): Iterator[Seq[B]]

    Takes longest prefix of values produced by this iterator that satisfy a predicate.

    Takes longest prefix of values produced by this iterator that satisfy a predicate.

    p

      The predicate used to test elements.

    returns

      An iterator returning the values produced by this iterator, until this iterator produces a value that does not satisfy the predicate `p`.

    Definition Classes
      Iterator
    Note

      Reuse: After calling this method, one should discard the iterator it was called on, and use only the iterator that was returned. Using the old iterator is undefined, subject to change, and may result in changes to the new iterator as well.

97. #### abstract def toArray: Array[Seq[B]]

    [use case] Converts this traversable or iterator to an array.

    [use case]

    Converts this traversable or iterator to an array.

    Note: will not terminate for infinite iterators.

    returns

      an array containing all elements of this traversable or iterator.

    Definition Classes
      GenTraversableOnce

98. #### def toArray[B >: Seq[B]](implicit arg0: ClassManifest[B]): Array[B]

    Converts this traversable or iterator to an array.

    Converts this traversable or iterator to an array.

    Note: will not terminate for infinite iterators.

    B

      the type of the elements of the array. A `ClassManifest` for this type must be available.

    returns

      an array containing all elements of this traversable or iterator.

    Definition Classes
      TraversableOnce → GenTraversableOnce

99. #### def toBuffer[B >: Seq[B]]: Buffer[B]

    Converts this traversable or iterator to a mutable buffer.

    Converts this traversable or iterator to a mutable buffer.

    Note: will not terminate for infinite iterators.

    returns

      a buffer containing all elements of this traversable or iterator.

    Definition Classes
      TraversableOnce → GenTraversableOnce

100. #### def toIndexedSeq[B >: Seq[B]]: IndexedSeq[B]

     Converts this traversable or iterator to an indexed sequence.

     Converts this traversable or iterator to an indexed sequence.

     Note: will not terminate for infinite iterators.

     returns

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

     Definition Classes
       TraversableOnce → GenTraversableOnce

101. #### def toIterable: Iterable[Seq[B]]

     Converts this traversable or iterator to an iterable collection.

     Converts this traversable 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 iterators.

     returns

       an `Iterable` containing all elements of this traversable or iterator.

     Definition Classes
       TraversableOnce → GenTraversableOnce

102. #### def toIterator: Iterator[Seq[B]]

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

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

     Note: will not terminate for infinite iterators.

     returns

       an Iterator containing all elements of this traversable or iterator.

     Definition Classes
       Iterator → GenTraversableOnce

103. #### def toList: List[Seq[B]]

     Converts this traversable or iterator to a list.

     Converts this traversable or iterator to a list.

     Note: will not terminate for infinite iterators.

     returns

       a list containing all elements of this traversable or iterator.

     Definition Classes
       TraversableOnce → GenTraversableOnce

104. #### abstract def toMap[T, U]: Map[T, U]

     [use case] Converts this traversable or iterator to a map.

     [use case]

     Converts this traversable or iterator 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 iterators.

     returns

       a map containing all elements of this traversable or iterator.

     Definition Classes
       GenTraversableOnce

105. #### def toMap[T, U](implicit ev: <:<[Seq[B], (T, U)]): Map[T, U]

     Converts this traversable or iterator to a map.

     Converts this traversable or iterator 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 iterators.

     returns

       a map containing all elements of this traversable or iterator.

     Definition Classes
       TraversableOnce → GenTraversableOnce

106. #### def toSeq: Seq[Seq[B]]

     Converts this traversable or iterator to a sequence.

     Converts this traversable or iterator 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 iterators.

     returns

       a sequence containing all elements of this traversable or iterator.

     Definition Classes
       TraversableOnce → GenTraversableOnce

107. #### def toSet[B >: Seq[B]]: Set[B]

     Converts this traversable or iterator to a set.

     Converts this traversable or iterator to a set.

     Note: will not terminate for infinite iterators.

     returns

       a set containing all elements of this traversable or iterator.

     Definition Classes
       TraversableOnce → GenTraversableOnce

108. #### def toStream: Stream[Seq[B]]

     Converts this traversable or iterator to a stream.

     Converts this traversable or iterator to a stream.

     Note: will not terminate for infinite iterators.

     returns

       a stream containing all elements of this traversable or iterator.

     Definition Classes
       Iterator → GenTraversableOnce

109. #### def toString(): String

     Converts this iterator to a string.

     Converts this iterator to a string.

     returns

       `"empty iterator"` or `"non-empty iterator"`, depending on whether or not the iterator is empty.

     Definition Classes
       Iterator → AnyRef → Any
     Note

       Reuse: The iterator remains valid for further use whatever result is returned.

110. #### def toTraversable: Traversable[Seq[B]]

     Converts this traversable or iterator to an unspecified Traversable.

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

     Note: will not terminate for infinite iterators.

     returns

       a Traversable containing all elements of this traversable or iterator.

     Definition Classes
       Iterator → TraversableOnce → GenTraversableOnce

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

     Definition Classes
       AnyRef
     Annotations
       @throws()

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

     Definition Classes
       AnyRef
     Annotations
       @throws()

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

     Definition Classes
       AnyRef
     Annotations
       @throws()

114. #### def withFilter(p: (Seq[B]) ⇒ Boolean): Iterator[Seq[B]]

     Creates an iterator over all the elements of this iterator that satisfy the predicate `p`.

     Creates an iterator over all the elements of this iterator that satisfy the predicate `p`. The order of the elements is preserved.

     Note: `withFilter` is the same as `filter` on iterators. It exists so that for-expressions with filters work over iterators.

     p

       the predicate used to test values.

     returns

       an iterator which produces those values of this iterator which satisfy the predicate `p`.

     Definition Classes
       Iterator
     Note

       Reuse: After calling this method, one should discard the iterator it was called on, and use only the iterator that was returned. Using the old iterator is undefined, subject to change, and may result in changes to the new iterator as well.

115. #### def withPadding(x: ⇒ B): GroupedIterator.this.type

     Public functions which can be used to configure the iterator before use.

     Public functions which can be used to configure the iterator before use.

     Pads the last segment if necessary so that all segments will have the same size.

     x

       The element that will be appended to the last segment, if necessary.

     returns

       The same iterator, and not a new iterator.

     Note

       This method is mutually exclusive with `withPartial(true)`.

       ,

       This method mutates the iterator it is called on, which can be safely used afterwards.

116. #### def withPartial(x: Boolean): GroupedIterator.this.type

     Public functions which can be used to configure the iterator before use.

     Public functions which can be used to configure the iterator before use.

     Select whether the last segment may be returned with less than `size` elements. If not, some elements of the original iterator may not be returned at all.

     x

       `true` if partial segments may be returned, `false` otherwise.

     returns

       The same iterator, and not a new iterator.

     Note

       This method is mutually exclusive with `withPadding`.

       ,

       This method mutates the iterator it is called on, which can be safely used afterwards.

117. #### def zip[B](that: Iterator[B]): Iterator[(Seq[B], B)]

     Creates an iterator formed from this iterator and another iterator by combining corresponding values in pairs.

     Creates an iterator formed from this iterator and another iterator by combining corresponding values in pairs. If one of the two iterators is longer than the other, its remaining elements are ignored.

     that

       The iterator providing the second half of each result pair

     returns

       a new iterator containing pairs consisting of corresponding elements of this iterator and `that`. The number of elements returned by the new iterator is the minimum of the number of elements returned by this iterator and `that`.

     Definition Classes
       Iterator
     Note

       Reuse: After calling this method, one should discard the iterator it was called on, as well as the one passed as a parameter, and use only the iterator that was returned. Using the old iterators is undefined, subject to change, and may result in changes to the new iterator as well.

118. #### abstract def zipAll[B](that: Iterator[B], thisElem: Seq[B], thatElem: B): Iterator[(Seq[B], B)]

     [use case] Creates an iterator formed from this iterator and another iterator by combining corresponding elements in pairs.

     [use case]

     Creates an iterator formed from this iterator and another iterator by combining corresponding elements in pairs. If one of the two iterators is shorter than the other, placeholder elements are used to extend the shorter iterator to the length of the longer.

     that

       iterator `that` may have a different length as the self iterator.

     thisElem

       element `thisElem` is used to fill up the resulting iterator if the self iterator is shorter than `that`

     thatElem

       element `thatElem` is used to fill up the resulting iterator if `that` is shorter than the self iterator

     returns

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

     Definition Classes
       Iterator

119. #### def zipAll[B, A1 >: Seq[B], B1 >: B](that: Iterator[B], thisElem: A1, thatElem: B1): Iterator[(A1, B1)]

     Creates an iterator formed from this iterator and another iterator by combining corresponding elements in pairs.

     Creates an iterator formed from this iterator and another iterator by combining corresponding elements in pairs. If one of the two iterators is shorter than the other, placeholder elements are used to extend the shorter iterator to the length of the longer.

     that

       iterator `that` may have a different length as the self iterator.

     thisElem

       element `thisElem` is used to fill up the resulting iterator if the self iterator is shorter than `that`

     thatElem

       element `thatElem` is used to fill up the resulting iterator if `that` is shorter than the self iterator

     returns

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

     Definition Classes
       Iterator
     Note

       Reuse: After calling this method, one should discard the iterator it was called on, as well as the one passed as a parameter, and use only the iterator that was returned. Using the old iterators is undefined, subject to change, and may result in changes to the new iterator as well.

120. #### def zipWithIndex: Iterator[(Seq[B], Int)] { ... /* 2 definitions in type refinement */ }

     Creates an iterator that pairs each element produced by this iterator with its index, counting from 0.

     Creates an iterator that pairs each element produced by this iterator with its index, counting from 0.

     returns

       a new iterator containing pairs consisting of corresponding elements of this iterator and their indices.

     Definition Classes
       Iterator
     Note

       Reuse: After calling this method, one should discard the iterator it was called on, and use only the iterator that was returned. Using the old iterator is undefined, subject to change, and may result in changes to the new iterator as well.

### Deprecated Value Members

1. #### def append[B >: Seq[B]](that: Iterator[B]): Iterator[B]

   Returns a new iterator that first yields the elements of this iterator followed by the elements provided by iterator `that`.

   Returns a new iterator that first yields the elements of this iterator followed by the elements provided by iterator `that`.

   Definition Classes
     Iterator
   Annotations
     @deprecated
   Deprecated

     (Since version 2.3.2) use `++`

2. #### def counted: CountedIterator[Seq[B]]

   Returns a counted iterator from this iterator.

   Returns a counted iterator from this iterator.

   Definition Classes
     Iterator
   Annotations
     @deprecated
   Deprecated

     (Since version 2.8.0) use zipWithIndex in Iterator

3. #### def findIndexOf(p: (Seq[B]) ⇒ Boolean): Int

   Returns index of the first element satisfying a predicate, or -1.

   Returns index of the first element satisfying a predicate, or -1.

   Definition Classes
     Iterator
   Annotations
     @deprecated
   Deprecated

     (Since version 2.8.0) use `indexWhere` instead

4. #### def readInto[B >: Seq[B]](xs: Array[B]): Unit

   Definition Classes
     Iterator
   Annotations
     @deprecated
   Deprecated

     (Since version 2.8.0) use copyToArray instead

5. #### def readInto[B >: Seq[B]](xs: Array[B], start: Int): Unit

   Definition Classes
     Iterator
   Annotations
     @deprecated
   Deprecated

     (Since version 2.8.0) use copyToArray instead

6. #### def readInto[B >: Seq[B]](xs: Array[B], start: Int, sz: Int): Unit

   Fills the given array `xs` with the elements of this sequence starting at position `start`.

   Fills the given array `xs` with the elements of this sequence starting at position `start`. Like `copyToArray`, but designed to accomodate IO stream operations.

   Note: the array must be large enough to hold `sz` elements.

   xs

     the array to fill.

   start

     the starting index.

   sz

     the maximum number of elements to be read.

   Definition Classes
     Iterator
   Annotations
     @deprecated
   Deprecated

     (Since version 2.8.0) use copyToArray instead

### Inherited from Iterator[Seq[B]]

### Inherited from TraversableOnce[Seq[B]]

### Inherited from GenTraversableOnce[Seq[B]]

### Inherited from AnyRef

### Inherited from Any