Class scala.collection.immutable.VectorIterator
class VectorIterator[+A] extends AbstractIterator[A] with VectorPointer[A]
Type Members
class GroupedIterator[B >: A] extends AbstractIterator[immutable.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
.
- Definition Classes
- Iterator
Value Members
final def !=(arg0: Any): Boolean
Test two objects for inequality.
- returns
true
if !(this == that), false otherwise.
- Definition Classes
- AnyRef → Any
final def ##(): Int
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
- AnyRef → Any
def +(other: String): String
- Implicit
- This member is added by an implicit conversion from VectorIterator[A] toany2stringadd[VectorIterator[A]] performed by method any2stringadd in scala.Predef.
- Definition Classes
- any2stringadd
final def ++[B >: A](xs: => IterableOnce[B]): Iterator[B]
def ->[B](y: B): (VectorIterator[A], B)
- Implicit
- This member is added by an implicit conversion from VectorIterator[A] toArrowAssoc[VectorIterator[A]] performed by method ArrowAssoc in scala.Predef.
- Definition Classes
- ArrowAssoc
- Annotations
- @inline()
final def ==(arg0: Any): Boolean
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
- AnyRef → Any
final def addString(b: mutable.StringBuilder): mutable.StringBuilder
Appends all elements of this collection to a string builder. The written text consists of the string representations (w.r.t. the method toString
) of all elements of this collection without any separator string.
Example:
scala> val a = List(1,2,3,4) a: List[Int] = List(1, 2, 3, 4) scala> val b = new StringBuilder() b: StringBuilder = scala> val h = a.addString(b) h: StringBuilder = 1234
- b
the string builder to which elements are appended.
- returns
the string builder
b
to which elements were appended.
- Definition Classes
- IterableOnceOps
- Annotations
- @inline()
final def addString(b: mutable.StringBuilder, sep: String): mutable.StringBuilder
Appends all elements of this collection 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 collection, separated by the string sep
.
Example:
scala> val a = List(1,2,3,4) a: List[Int] = List(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
- IterableOnceOps
- Annotations
- @inline()
def addString(b: mutable.StringBuilder, start: String, sep: String, end: String): mutable.StringBuilder
Appends all elements of this collection 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 collection are separated by the string sep
.
Example:
scala> val a = List(1,2,3,4) a: List[Int] = List(1, 2, 3, 4) scala> val b = new StringBuilder() b: StringBuilder = scala> a.addString(b , "List(" , ", " , ")") res5: StringBuilder = List(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
- IterableOnceOps
final def asInstanceOf[T0]: 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 typeT0
.
def buffered: BufferedIterator[A]
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
def clone(): AnyRef
Create a copy of the receiver object.
The default implementation of the clone
method is platform dependent.
- returns
a copy of the receiver object.
def collect[B](pf: PartialFunction[A, B]): Iterator[B]
Builds a new iterator by applying a partial function to all elements of this iterator on which the function is defined.
- B
the element type of the returned iterator.
- pf
the partial function which filters and maps the iterator.
- returns
a new iterator 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
- Iterator → IterableOnceOps
- 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.
def collectFirst[B](pf: PartialFunction[A, B]): Option[B]
Finds the first element of the collection for which the given partial function is defined, and applies the partial function to it.
Note: may not terminate for infinite-sized collections.
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
- IterableOnceOps
Seq("a", 1, 5L).collectFirst({ case x: Int => x*10 }) = Some(10)
def concat[B >: A](xs: => IterableOnce[B]): Iterator[B]
- Definition Classes
- Iterator
def contains(elem: Any): Boolean
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 (as determined by==
) toelem
,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.
def copyToArray[B >: A](xs: Array[B], start: Int, len: Int): Int
Copy elements to an array, returning the number of elements written.
Fills the given array xs
starting at index start
with at most len
elements of this iterator.
Copying will stop once either all the elements of this iterator have been copied, or the end of the array is reached, or len
elements have been copied.
- B
the type of the elements of the array.
- xs
the array to fill.
- start
the starting index of xs.
- len
the maximal number of elements to copy.
- returns
the number of elements written to the array
- Definition Classes
- VectorIterator → IterableOnceOps
- Note
Reuse: After calling this method, one should discard the iterator it was called on. Using it is undefined and subject to change. Note: will not terminate for infinite-sized collections.
def copyToArray[B >: A](xs: Array[B], start: Int): Int
Copy elements to an array, returning the number of elements written.
Fills the given array xs
starting at index start
with values of this collection.
Copying will stop once either all the elements of this collection have been copied, or the end of the array is reached.
- B
the type of the elements of the array.
- xs
the array to fill.
- start
the starting index of xs.
- returns
the number of elements written to the array Note: will not terminate for infinite-sized collections.
- Definition Classes
- IterableOnceOps
def copyToArray[B >: A](xs: Array[B]): Int
Copy elements to an array, returning the number of elements written.
Fills the given array xs
starting at index start
with values of this collection.
Copying will stop once either all the elements of this collection have been copied, or the end of the array is reached.
- B
the type of the elements of the array.
- xs
the array to fill.
- returns
the number of elements written to the array Note: will not terminate for infinite-sized collections.
- Definition Classes
- IterableOnceOps
def corresponds[B](that: IterableOnce[B])(p: (A, B) => Boolean): Boolean
Tests whether every element of this collection's iterator relates to the corresponding element of another collection by satisfying a test predicate.
- B
the type of the elements of
that
- that
the other collection
- p
the test predicate, which relates elements from both collections
- returns
true
if both collections have the same length andp(x, y)
istrue
for all corresponding elementsx
of this iterator andy
ofthat
, otherwisefalse
- Definition Classes
- IterableOnceOps
def count(p: (A) => Boolean): Int
Counts the number of elements in the collection which satisfy a predicate.
- p
the predicate used to test elements.
- returns
the number of elements satisfying the predicate
p
.
- Definition Classes
- IterableOnceOps
def distinct: Iterator[A]
Builds a new iterator from this one without any duplicated elements on it.
- returns
iterator with distinct elements
- 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.
def distinctBy[B](f: (A) => B): Iterator[A]
Builds a new iterator from this one without any duplicated elements as determined by ==
after applying the transforming function f
.
- B
the type of the elements after being transformed by
f
- f
The transforming function whose result is used to determine the uniqueness of each element
- returns
iterator with distinct elements
- 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.
def drop(n: Int): Iterator[A]
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 iterator.
- returns
a iterator consisting of all elements of this iterator except the first
n
ones, or else the empty iterator, if this iterator has less thann
elements. Ifn
is negative, don't drop any elements.
- Definition Classes
- VectorIterator → Iterator → IterableOnceOps
- 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.
def dropWhile(p: (A) => Boolean): Iterator[A]
Drops longest prefix of elements that satisfy a predicate.
Note: might return different results for different runs, unless the underlying collection type is ordered.
- p
The predicate used to test elements.
- returns
the longest suffix of this iterator whose first element does not satisfy the predicate
p
.
- Definition Classes
- Iterator → IterableOnceOps
- 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.
def duplicate: (Iterator[A], Iterator[A])
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
-
The implementation may allocate temporary storage for elements iterated by one iterator but not yet by the other.
,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.
def ensuring(cond: (VectorIterator[A]) => Boolean, msg: => Any): VectorIterator[A]
- Implicit
- This member is added by an implicit conversion from VectorIterator[A] toEnsuring[VectorIterator[A]] performed by method Ensuring in scala.Predef.
- Definition Classes
- Ensuring
def ensuring(cond: (VectorIterator[A]) => Boolean): VectorIterator[A]
- Implicit
- This member is added by an implicit conversion from VectorIterator[A] toEnsuring[VectorIterator[A]] performed by method Ensuring in scala.Predef.
- Definition Classes
- Ensuring
def ensuring(cond: Boolean, msg: => Any): VectorIterator[A]
- Implicit
- This member is added by an implicit conversion from VectorIterator[A] toEnsuring[VectorIterator[A]] performed by method Ensuring in scala.Predef.
- Definition Classes
- Ensuring
def ensuring(cond: Boolean): VectorIterator[A]
- Implicit
- This member is added by an implicit conversion from VectorIterator[A] toEnsuring[VectorIterator[A]] performed by method Ensuring in scala.Predef.
- Definition Classes
- Ensuring
final def eq(arg0: AnyRef): Boolean
Tests whether the argument (that
) 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
def equals(arg0: AnyRef): Boolean
The equality method for reference types. Default implementation delegates to eq
.
See also equals
in scala.Any.
- returns
true
if the receiver object is equivalent to the argument;false
otherwise.
- Definition Classes
- AnyRef → Any
def exists(p: (A) => Boolean): Boolean
Tests whether a predicate holds for at least one element of this collection.
Note: may not terminate for infinite-sized collections.
- p
the predicate used to test elements.
- returns
true
if the given predicatep
is satisfied by at least one element of this collection, otherwisefalse
- Definition Classes
- IterableOnceOps
def filter(p: (A) => Boolean): Iterator[A]
Selects all elements of this iterator which satisfy a predicate.
- p
the predicate used to test elements.
- returns
a new iterator consisting of all elements of this iterator that satisfy the given predicate
p
. The order of the elements is preserved.
- Definition Classes
- Iterator → IterableOnceOps
def filterNot(p: (A) => Boolean): Iterator[A]
Selects all elements of this iterator which do not satisfy a predicate.
- returns
a new iterator consisting of all elements of this iterator that do not satisfy the given predicate
pred
. Their order may not be preserved.
- Definition Classes
- Iterator → IterableOnceOps
def finalize(): Unit
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.
def find(p: (A) => Boolean): Option[A]
Finds the first element of the collection 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 that satisfies
p
, orNone
if none exists.
- Definition Classes
- IterableOnceOps
def flatMap[B](f: (A) => IterableOnce[B]): Iterator[B]
Builds a new iterator by applying a function to all elements of this iterator 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 iterator. 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: String) => 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 iterator resulting from applying the given collection-valued function
f
to each element of this iterator and concatenating the results.
- Definition Classes
- Iterator → IterableOnceOps
- 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.
def flatten[B](implicit ev: (A) => IterableOnce[B]): Iterator[B]
Converts this iterator of traversable collections into a iterator formed by the elements of these traversable collections.
The resulting collection's type will be guided by the type of iterator. For example:
val xs = List( Set(1, 2, 3), Set(1, 2, 3) ).flatten // xs == List(1, 2, 3, 1, 2, 3) val ys = Set( List(1, 2, 3), List(3, 2, 1) ).flatten // ys == Set(1, 2, 3)
- B
the type of the elements of each traversable collection.
- returns
a new iterator resulting from concatenating all element iterators.
- Definition Classes
- Iterator → IterableOnceOps
- 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.
def fold[A1 >: A](z: A1)(op: (A1, A1) => A1): A1
Folds the elements of this collection using the specified associative binary operator. The default implementation in IterableOnce
is equivalent to foldLeft
but may be overridden for more efficient traversal orders.
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 andz
, orz
if this collection is empty.
- Definition Classes
- IterableOnceOps
def foldLeft[B](z: B)(op: (B, A) => B): B
Applies a binary operator to a start value and all elements of this collection, 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, going left to right with the start valuez
on the left:op(...op(z, x_1), x_2, ..., x_n)
where
x1, ..., xn
are the elements of this collection. Returnsz
if this collection is empty.
- Definition Classes
- IterableOnceOps
def foldRight[B](z: B)(op: (A, B) => B): B
Applies a binary operator to all elements of this collection 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, going right to left with the start valuez
on the right:op(x_1, op(x_2, ... op(x_n, z)...))
where
x1, ..., xn
are the elements of this collection. Returnsz
if this collection is empty.
- Definition Classes
- IterableOnceOps
def forall(p: (A) => Boolean): Boolean
Tests whether a predicate holds for all elements of this collection.
Note: may not terminate for infinite-sized collections.
- p
the predicate used to test elements.
- returns
true
if this collection is empty or the given predicatep
holds for all elements of this collection, otherwisefalse
.
- Definition Classes
- IterableOnceOps
def foreach[U](f: (A) => U): Unit
Apply f
to each element for its side effects Note: [U] parameter needed to help scalac's type inference.
- Definition Classes
- IterableOnceOps
def formatted(fmtstr: String): 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 VectorIterator[A] toStringFormat[VectorIterator[A]] performed by method StringFormat in scala.Predef.
- Definition Classes
- StringFormat
- Annotations
- @inline()
final def getClass(): Class[_ <: AnyRef]
Returns the runtime class representation of the object.
- returns
a class object corresponding to the runtime type of the receiver.
def grouped[B >: A](size: Int): GroupedIterator[B]
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.
def hasNext: Boolean
Check if there is a next element available.
- returns
true
if there is a next element,false
otherwise
- Definition Classes
- VectorIterator → Iterator
- Note
Reuse: The iterator remains valid for further use whatever result is returned.
def hashCode(): Int
The hashCode method for reference types. See hashCode in scala.Any.
- returns
the hash code value for this object.
def indexOf[B >: A](elem: B, from: Int): Int
Returns the index of the first occurrence of the specified object in this iterable object after or at some start index.
Note: may not terminate for infinite iterators.
- elem
element to search for.
- from
the start index
- returns
the index
>= from
of the first occurrence ofelem
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.
def indexOf[B >: A](elem: B): Int
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.
def indexWhere(p: (A) => Boolean, from: Int = 0): Int
- Definition Classes
- Iterator
def isEmpty: Boolean
Tests whether the 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 iterator contains no elements,false
otherwise.
- Definition Classes
- Iterator → IterableOnceOps
- Annotations
- @deprecatedOverriding("isEmpty is defined as !hasNext; override hasNext instead", "2.13.0")
final def isInstanceOf[T0]: Boolean
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 typeT0
;false
otherwise.
- Definition Classes
- Any
def isTraversableAgain: Boolean
Tests whether this collection can be repeatedly traversed. Always true for Iterables and false for Iterators unless overridden.
- returns
true
if it is repeatedly traversable,false
otherwise.
- Definition Classes
- IterableOnceOps
final def iterator: Iterator[A]
Iterator can be used only once
- Definition Classes
- Iterator → IterableOnce
- Annotations
- @inline()
def knownSize: Int
- returns
The number of elements in this iterator, if it can be cheaply computed, -1 otherwise. Cheaply usually means: Not requiring a collection traversal.
- Definition Classes
- VectorIterator → IterableOnce
final def length: Int
def map[B](f: (A) => B): Iterator[B]
Builds a new iterator by applying a function to all elements of this iterator.
- B
the element type of the returned iterator.
- f
the function to apply to each element.
- returns
a new iterator resulting from applying the given function
f
to each element of this iterator and collecting the results.
- Definition Classes
- Iterator → IterableOnceOps
- 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.
def max[B >: A](implicit ord: math.Ordering[B]): A
Finds the largest element.
- B
The type over which the ordering is defined.
- ord
An ordering to be used for comparing elements.
- returns
the largest element of this collection with respect to the ordering
ord
.
- Definition Classes
- IterableOnceOps
- Exceptions thrown
UnsupportedOperationException
if this collection is empty.
def maxBy[B](f: (A) => B)(implicit cmp: math.Ordering[B]): A
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.
- cmp
An ordering to be used for comparing elements.
- returns
the first element of this collection with the largest value measured by function f with respect to the ordering
cmp
.
- Definition Classes
- IterableOnceOps
- Exceptions thrown
UnsupportedOperationException
if this collection is empty.
def maxByOption[B](f: (A) => B)(implicit cmp: math.Ordering[B]): Option[A]
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.
- cmp
An ordering to be used for comparing elements.
- returns
an option value containing the first element of this collection with the largest value measured by function f with respect to the ordering
cmp
.
- Definition Classes
- IterableOnceOps
def maxOption[B >: A](implicit ord: math.Ordering[B]): Option[A]
Finds the largest element.
- B
The type over which the ordering is defined.
- ord
An ordering to be used for comparing elements.
- returns
an option value containing the largest element of this collection with respect to the ordering
ord
.
- Definition Classes
- IterableOnceOps
def min[B >: A](implicit ord: math.Ordering[B]): A
Finds the smallest element.
- B
The type over which the ordering is defined.
- ord
An ordering to be used for comparing elements.
- returns
the smallest element of this collection with respect to the ordering
ord
.
- Definition Classes
- IterableOnceOps
- Exceptions thrown
UnsupportedOperationException
if this collection is empty.
def minBy[B](f: (A) => B)(implicit cmp: math.Ordering[B]): A
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.
- cmp
An ordering to be used for comparing elements.
- returns
the first element of this collection with the smallest value measured by function f with respect to the ordering
cmp
.
- Definition Classes
- IterableOnceOps
- Exceptions thrown
UnsupportedOperationException
if this collection is empty.
def minByOption[B](f: (A) => B)(implicit cmp: math.Ordering[B]): Option[A]
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.
- cmp
An ordering to be used for comparing elements.
- returns
an option value containing the first element of this collection with the smallest value measured by function f with respect to the ordering
cmp
.
- Definition Classes
- IterableOnceOps
def minOption[B >: A](implicit ord: math.Ordering[B]): Option[A]
Finds the smallest element.
- B
The type over which the ordering is defined.
- ord
An ordering to be used for comparing elements.
- returns
an option value containing the smallest element of this collection with respect to the ordering
ord
.
- Definition Classes
- IterableOnceOps
final def mkString: String
Displays all elements of this collection in a string.
Delegates to addString, which can be overridden.
- returns
a string representation of this collection. In the resulting string the string representations (w.r.t. the method
toString
) of all elements of this collection follow each other without any separator string.
- Definition Classes
- IterableOnceOps
- Annotations
- @inline()
final def mkString(sep: String): String
Displays all elements of this collection in a string using a separator string.
Delegates to addString, which can be overridden.
- sep
the separator string.
- returns
a string representation of this collection. In the resulting string the string representations (w.r.t. the method
toString
) of all elements of this collection are separated by the stringsep
.
- Definition Classes
- IterableOnceOps
- Annotations
- @inline()
List(1, 2, 3).mkString("|") = "1|2|3"
final def mkString(start: String, sep: String, end: String): String
Displays all elements of this collection in a string using start, end, and separator strings.
Delegates to addString, which can be overridden.
- start
the starting string.
- sep
the separator string.
- end
the ending string.
- returns
a string representation of this collection. The resulting string begins with the string
start
and ends with the stringend
. Inside, the string representations (w.r.t. the methodtoString
) of all elements of this collection are separated by the stringsep
.
- Definition Classes
- IterableOnceOps
List(1, 2, 3).mkString("(", "; ", ")") = "(1; 2; 3)"
final def ne(arg0: AnyRef): Boolean
Equivalent to !(this eq that)
.
- returns
true
if the argument is not a reference to the receiver object;false
otherwise.
- Definition Classes
- AnyRef
def next(): A
Return the next element and advance the iterator.
- returns
the next element.
- Definition Classes
- VectorIterator → Iterator
- Exceptions thrown
NoSuchElementException
if there is no next element.- Note
Reuse: Advances the iterator, which may exhaust the elements. It is valid to make additional calls on the iterator.
def nextOption(): Option[A]
Wraps the value of next()
in an option.
- returns
Some(next)
if a next element exists,None
otherwise.
- Definition Classes
- Iterator
def nonEmpty: Boolean
Tests whether the collection is not empty.
- returns
true
if the collection contains at least one element,false
otherwise.
- Definition Classes
- IterableOnceOps
- Annotations
- @deprecatedOverriding("nonEmpty is defined as !isEmpty; override isEmpty instead", "2.13.0")
final def notify(): Unit
Wakes up a single thread that is waiting on the receiver object's monitor.
- Definition Classes
- AnyRef
- Annotations
- @native()
- Note
not specified by SLS as a member of AnyRef
final def notifyAll(): Unit
Wakes up all threads that are waiting on the receiver object's monitor.
- Definition Classes
- AnyRef
- Annotations
- @native()
- Note
not specified by SLS as a member of AnyRef
def padTo[B >: A](len: Int, elem: B): Iterator[B]
A copy of this iterator with an element value appended until a given target length is reached.
- B
the element type of the returned iterator.
- len
the target length
- elem
the padding value
- returns
a new iterator consisting of all elements of this iterator followed by the minimal number of occurrences of
elem
so that the resulting collection has a length of at leastlen
.
- Definition Classes
- Iterator
def partition(p: (A) => Boolean): (Iterator[A], Iterator[A])
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.
def patch[B >: A](from: Int, patchElems: Iterator[B], replaced: Int): Iterator[B]
Returns this iterator with patched values. Patching at negative indices is the same as patching starting at 0. Patching at indices at or larger than the length of the original iterator appends the patch to the end. If more values are replaced than actually exist, the excess is ignored.
- 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.
def preClean(depth: Int): Unit
- Attributes
- protected
- Definition Classes
- VectorPointer
def product[B >: A](implicit num: math.Numeric[B]): B
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 collection with respect to the
*
operator innum
.
- Definition Classes
- IterableOnceOps
def reduce[B >: A](op: (B, B) => B): B
Reduces the elements of this collection using the specified associative binary operator.
The order in which operations are performed on elements is unspecified and may be nondeterministic.
- B
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 is nonempty.
- Definition Classes
- IterableOnceOps
- Exceptions thrown
UnsupportedOperationException
if this collection is empty.
def reduceLeft[B >: A](op: (B, A) => B): B
Applies a binary operator to all elements of this collection, 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
-
the result of inserting
op
between consecutive elements of this collection, going left to right:op( op( ... op(x_1, x_2) ..., x_{n-1}), x_n)
where
x1, ..., xn
are the elements of this collection.
- Definition Classes
- IterableOnceOps
- Exceptions thrown
UnsupportedOperationException
if this collection is empty.
def reduceLeftOption[B >: A](op: (B, A) => B): Option[B]
Optionally applies a binary operator to all elements of this collection, 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 is nonempty,None
otherwise.
- Definition Classes
- IterableOnceOps
def reduceOption[B >: A](op: (B, B) => B): Option[B]
Reduces the elements of this collection, if any, using the specified associative binary operator.
The order in which operations are performed on elements is unspecified and may be nondeterministic.
- B
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, andNone
otherwise.
- Definition Classes
- IterableOnceOps
def reduceRight[B >: A](op: (A, B) => B): B
Applies a binary operator to all elements of this collection, 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, 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.
- Definition Classes
- IterableOnceOps
- Exceptions thrown
UnsupportedOperationException
if this collection is empty.
def reduceRightOption[B >: A](op: (A, B) => B): Option[B]
Optionally applies a binary operator to all elements of this collection, 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 is nonempty,None
otherwise.
- Definition Classes
- IterableOnceOps
def reversed: collection.Iterable[A]
- Attributes
- protected
- Definition Classes
- IterableOnceOps
def sameElements[B >: A](that: IterableOnce[B]): Boolean
- Definition Classes
- Iterator
def scanLeft[B](z: B)(op: (B, A) => B): Iterator[B]
Produces a iterator containing cumulative results of applying the operator going left to right, including the initial value.
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
- z
the initial value
- op
the binary operator applied to the intermediate result and the element
- returns
collection with intermediate results
- Definition Classes
- Iterator → IterableOnceOps
- 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.
def size: Int
The size of this collection.
Note: will not terminate for infinite-sized collections.
- returns
the number of elements in this collection.
- Definition Classes
- IterableOnceOps
def slice(from: Int, until: Int): Iterator[A]
Selects an interval of elements. The returned iterator 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.
- from
the lowest index to include from this iterator.
- until
the lowest index to EXCLUDE from this iterator.
- returns
a iterator containing the elements greater than or equal to index
from
extending up to (but not including) indexuntil
of this iterator.
- Definition Classes
- VectorIterator → Iterator → IterableOnceOps
- 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.
def sliceIterator(from: Int, until: Int): Iterator[A]
Creates an optionally bounded slice, unbounded if until
is negative.
- Attributes
- protected
- Definition Classes
- Iterator
def sliding[B >: A](size: Int, step: Int = 1): GroupedIterator[B]
Returns an iterator which presents a "sliding window" view of this iterator. The first argument is the window size, and the second argument step
is how far to advance the window on each iteration. The step
defaults to 1
.
The default GroupedIterator
can be configured to either pad a partial result to size size
or suppress the partial result entirely.
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
- returns
An iterator producing
Seq[B]
s of sizesize
, except the last element (which may be the only element) will be truncated if there are fewer thansize
elements remaining to be grouped. This behavior can be configured.
- 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.
def span(p: (A) => Boolean): (Iterator[A], Iterator[A])
Splits this iterator 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.
- p
the test predicate
- returns
a pair consisting of the longest prefix of this iterator whose elements all satisfy
p
, and the rest of this iterator.
- Definition Classes
- Iterator → IterableOnceOps
- 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.
def splitAt(n: Int): (Iterator[A], Iterator[A])
Splits this collection into a prefix/suffix pair 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 collections consisting of the first
n
elements of this collection, and the other elements.
- Definition Classes
- IterableOnceOps
- 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.
def stepper[S <: Stepper[_]](implicit shape: StepperShape[A, S]): S
Returns a Stepper for the elements of this collection.
The Stepper enables creating a Java stream to operate on the collection, see scala.jdk.StreamConverters. For collections holding primitive values, the Stepper can be used as an iterator which doesn't box the elements.
The implicit StepperShape parameter defines the resulting Stepper type according to the element type of this collection.
-
For collections of
Int
, Short
, Byte
or Char
, an IntStepper is returnedFor collections of Double
or Float
, a DoubleStepper is returnedFor collections of Long
a LongStepper is returnedFor any other element type, an AnyStepper is returnedNote that this method is overridden in subclasses and the return type is refined to S with EfficientSplit
, for example IndexedSeqOps.stepper. For Steppers marked with scala.collection.Stepper.EfficientSplit, the converters in scala.jdk.StreamConverters allow creating parallel streams, whereas bare Steppers can be converted only to sequential streams.
- Definition Classes
- IterableOnce
def sum[B >: A](implicit num: math.Numeric[B]): B
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 collection with respect to the
+
operator innum
.
- Definition Classes
- IterableOnceOps
final def synchronized[T0](arg0: => T0): T0
- Definition Classes
- AnyRef
def take(n: Int): Iterator[A]
Selects the 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 iterator.
- returns
a iterator consisting only of the first
n
elements of this iterator, or else the whole iterator, if it has less thann
elements. Ifn
is negative, returns an empty iterator.
- Definition Classes
- VectorIterator → Iterator → IterableOnceOps
- 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.
def takeWhile(p: (A) => Boolean): Iterator[A]
Takes longest prefix of elements that satisfy a predicate.
Note: might return different results for different runs, unless the underlying collection type is ordered.
- p
The predicate used to test elements.
- returns
the longest prefix of this iterator whose elements all satisfy the predicate
p
.
- Definition Classes
- Iterator → IterableOnceOps
- 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.
def tapEach[U](f: (A) => U): Iterator[A]
Applies a side-effecting function to each element in this collection. Strict collections will apply f
to their elements immediately, while lazy collections like Views and LazyLists will only apply f
on each element if and when that element is evaluated, and each time that element is evaluated.
- U
the return type of f
- f
a function to apply to each element in this iterator
- returns
The same logical collection as this
- Definition Classes
- Iterator → IterableOnceOps
def to[C1](factory: Factory[A, C1]): C1
Given a collection factory factory
, convert this collection to the appropriate representation for the current element type A
. Example uses:
xs.to(List) xs.to(ArrayBuffer) xs.to(BitSet) // for xs: Iterable[Int]
- Definition Classes
- IterableOnceOps
def toArray[B >: A](implicit arg0: ClassTag[B]): Array[B]
Convert collection to array.
- Definition Classes
- IterableOnceOps
final def toBuffer[B >: A]: Buffer[B]
- Definition Classes
- IterableOnceOps
- Annotations
- @inline()
def toIndexedSeq: IndexedSeq[A]
- Definition Classes
- IterableOnceOps
def toList: List[A]
- Definition Classes
- IterableOnceOps
def toMap[K, V](implicit ev: <:<[A, (K, V)]): Map[K, V]
- Definition Classes
- IterableOnceOps
def toSeq: Seq[A]
- returns
This collection as a
Seq[A]
. This is equivalent toto(Seq)
but might be faster.
- Definition Classes
- IterableOnceOps
def toSet[B >: A]: Set[B]
- Definition Classes
- IterableOnceOps
def toString(): String
Converts this iterator to a string.
- returns
"<iterator>"
def toVector: Vector[A]
- Definition Classes
- IterableOnceOps
final def wait(): Unit
- Definition Classes
- AnyRef
- Annotations
- @throws(classOf[java.lang.InterruptedException])
final def wait(arg0: Long, arg1: Int): Unit
- Definition Classes
- AnyRef
- Annotations
- @throws(classOf[java.lang.InterruptedException])
final def wait(arg0: Long): Unit
def withFilter(p: (A) => Boolean): Iterator[A]
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.
def zip[B](that: IterableOnce[B]): Iterator[(A, B)]
- Definition Classes
- Iterator
def zipAll[A1 >: A, B](that: IterableOnce[B], thisElem: A1, thatElem: B): Iterator[(A1, B)]
- Definition Classes
- Iterator
def zipWithIndex: Iterator[(A, Int)]
Zips this iterator with its indices.
- returns
A new iterator containing pairs consisting of all elements of this iterator paired with their index. Indices start at
0
.
- Definition Classes
- Iterator → IterableOnceOps
- 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.
List("a", "b", "c").zipWithIndex == List(("a", 0), ("b", 1), ("c", 2))
© 2002-2019 EPFL, with contributions from Lightbend.
Licensed under the Apache License, Version 2.0.
https://www.scala-lang.org/api/2.13.0/scala/collection/immutable/VectorIterator.html
(Since version 2.13.0) This class is not intended for public consumption and will be made private in the future.