trait Splitter[+T] extends Iterator[T]
A splitter (or a split iterator) can be split into more splitters that traverse over disjoint subsets of elements.
- T
type of the elements this splitter traverses
- Source
- Splitter.scala
- Since
2.9
- Alphabetic
- By Inheritance
- Splitter
- Iterator
- TraversableOnce
- GenTraversableOnce
- AnyRef
- Any
- by MonadOps
- by CollectionsHaveToParArray
- by any2stringadd
- by StringFormat
- by Ensuring
- by ArrowAssoc
- by alternateImplicit
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Type Members
-
class
GroupedIterator[B >: A] extends AbstractIterator[Seq[B]] with 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.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
andsliding
.- Definition Classes
- Iterator
Abstract Value Members
-
abstract
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 tonext
will yield an element,false
otherwise.
- Definition Classes
- Iterator
- Note
Reuse: The iterator remains valid for further use whatever result is returned.
-
abstract
def
next(): T
Produces the next element of this iterator.
Produces the next element of this iterator.
- returns
the next element of this iterator, if
hasNext
istrue
, undefined behavior otherwise.
- Definition Classes
- Iterator
- Note
Reuse: The iterator remains valid for further use whatever result is returned.
-
abstract
def
split: Seq[Splitter[T]]
Splits the iterator into a sequence of disjunct views.
Splits the iterator into a sequence of disjunct views.
Returns a sequence of split iterators, each iterating over some subset of the elements in the collection. These subsets are disjoint and should be approximately equal in size. These subsets are not empty, unless the iterator is empty in which case this method returns a sequence with a single empty iterator. If the splitter has more than two elements, this method will return two or more splitters.
Implementors are advised to keep this partition relatively small - two splitters are already enough when partitioning the collection, although there may be a few more.
Note: this method actually invalidates the current splitter.
- returns
a sequence of disjunct iterators of the collection
Concrete Value Members
-
def
++(that: ⇒ Iterator[T]): Iterator[T]
[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
Full Signaturedef ++[B >: T](that: ⇒ GenTraversableOnce[B]): Iterator[B]
-
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 = 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
- TraversableOnce
-
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 stringsep
.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
- TraversableOnce
-
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 stringend
. Inside, the string representations (w.r.t. the methodtoString
) of all elements of this traversable or iterator are separated by the stringsep
.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
- TraversableOnce
-
def
aggregate[B](z: ⇒ B)(seqop: (B, T) ⇒ 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
andreduce
. It is similar tofoldLeft
in that it doesn't require the result to be a supertype of the element type. In addition, it allows parallel collections to be processed in chunks, and then combines the intermediate results.aggregate
splits the traversable or iterator into partitions and processes each partition by sequentially applyingseqop
, starting withz
(likefoldLeft
). Those intermediate results are then combined by usingcombop
(likefold
). The implementation of this operation may operate on an arbitrary number of collection partitions (even 1), socombop
may be invoked an arbitrary number of times (even 0).As an example, consider summing up the integer values of a list of chars. The initial value for the sum is 0. First,
seqop
transforms each input character to an Int and adds it to the sum (of the partition). Then,combop
just needs to sum up the intermediate results of the partitions:List('a', 'b', 'c').aggregate(0)({ (sum, ch) => sum + ch.toInt }, { (p1, p2) => p1 + p2 })
- B
the type of accumulated results
- z
the initial value for the accumulated result of the partition - this will typically be the neutral element for the
seqop
operator (e.g.Nil
for list concatenation or0
for summation) and may be evaluated more than once- seqop
an operator used to accumulate results within a partition
- combop
an associative operator used to combine results from different partitions
- Definition Classes
- TraversableOnce → GenTraversableOnce
-
def
buffered: BufferedIterator[T]
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
-
def
collect[B](pf: PartialFunction[T, 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 whichpf
is defined the imagepf(x)
.
- Definition Classes
- Iterator
- Annotations
- @migration
- Migration
(Changed in version 2.8.0)
collect
has changed. The previous behavior can be reproduced withtoSeq
.- 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[T, 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-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
- TraversableOnce
Seq("a", 1, 5L).collectFirst({ case x: Int => x*10 }) = Some(10)
Example: -
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 (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(xs: Array[T], 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 indexstart
with at mostlen
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, orlen
elements have been copied.Note: will not terminate for infinite iterators.
- xs
the array to fill.
- start
the starting index.
- len
the maximal number of elements to copy.
- Definition Classes
- Iterator → TraversableOnce → GenTraversableOnce
-
def
copyToArray(xs: Array[A]): Unit
[use case] Copies the elements of this traversable or iterator to an array.
[use case]Copies the elements 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 target array is reached.Note: will not terminate for infinite iterators.
- xs
the array to fill.
- Definition Classes
- TraversableOnce → GenTraversableOnce
-
def
copyToArray(xs: Array[A], start: Int): Unit
[use case] Copies the elements of this traversable or iterator to an array.
[use case]Copies the elements of this traversable or iterator to an array. Fills the given array
xs
with values of this traversable or iterator, beginning at indexstart
. Copying will stop once either the end of the current traversable or iterator is reached, or the end of the target array is reached.Note: will not terminate for infinite iterators.
- xs
the array to fill.
- start
the starting index.
- Definition Classes
- TraversableOnce → GenTraversableOnce
-
def
copyToBuffer[B >: T](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-sized collections.
- dest
The buffer to which elements are copied.
- Definition Classes
- TraversableOnce
-
def
corresponds[B](that: GenTraversableOnce[B])(p: (T, B) ⇒ Boolean): Boolean
Tests whether every element of this iterator relates to the corresponding element of another collection by satisfying a test predicate.
Tests whether every element of this 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
- Iterator
-
def
count(p: (T) ⇒ 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
-
def
drop(n: Int): Iterator[T]
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.
-
def
dropWhile(p: (T) ⇒ Boolean): Iterator[T]
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.
-
def
duplicate: (Iterator[T], Iterator[T])
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
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
exists(p: (T) ⇒ 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 predicatep
holds for some of the values produced by this iterator, otherwisefalse
.
- 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.
-
def
filter(p: (T) ⇒ Boolean): Iterator[T]
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.
-
def
filterNot(p: (T) ⇒ Boolean): Iterator[T]
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.
-
def
find(p: (T) ⇒ Boolean): Option[T]
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
, orNone
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.
-
def
flatMap[B](f: (T) ⇒ 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.
-
def
fold[A1 >: T](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.
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 traversable or iterator is empty.
- Definition Classes
- TraversableOnce → GenTraversableOnce
-
def
foldLeft[B](z: B)(op: (B, T) ⇒ 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-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 traversable or iterator, 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 traversable or iterator. Returnsz
if this traversable or iterator is empty.
- Definition Classes
- TraversableOnce → GenTraversableOnce
-
def
foldRight[B](z: B)(op: (T, 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-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 traversable or iterator, 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 traversable or iterator. Returnsz
if this traversable or iterator is empty.
- Definition Classes
- TraversableOnce → GenTraversableOnce
-
def
forall(p: (T) ⇒ 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 predicatep
holds for all values produced by this iterator, otherwisefalse
.
- 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.
-
def
foreach(f: (T) ⇒ 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 → TraversableOnce → GenTraversableOnce
Full Signaturedef foreach[U](f: (T) ⇒ U): Unit
-
def
grouped[B >: T](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.
-
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.
-
def
indexOf[B >: T](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.
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 >: T](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.
-
def
indexWhere(p: (T) ⇒ Boolean, from: Int): Int
Returns the index of the first produced value satisfying a predicate, or -1, after or at some start index.
Returns the index of the first produced value satisfying a predicate, or -1, after or at some start index.
Note: may not terminate for infinite iterators.
- p
the predicate to test values
- from
the start index
- returns
the index
>= from
of the first produced value satisfyingp
, 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: (T) ⇒ 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.
-
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.
-
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.
-
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.
-
def
map[B](f: (T) ⇒ 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.
-
def
max: A
[use case] Finds the largest element.
[use case]Finds the largest element.
- returns
the largest element of this traversable or iterator.
- Definition Classes
- TraversableOnce → GenTraversableOnce
- Exceptions thrown
UnsupportedOperationException
if this traversable or iterator is empty.
Full Signaturedef max[B >: T](implicit cmp: Ordering[B]): T
-
def
maxBy[B](f: (A) ⇒ B): A
[use case] Finds the first element which yields the largest value measured by function f.
[use case]Finds the first element which yields the largest value measured by function f.
- B
The result type of the function f.
- f
The measuring function.
- returns
the first element of this traversable or iterator with the largest value measured by function f.
- Definition Classes
- TraversableOnce → GenTraversableOnce
- Exceptions thrown
UnsupportedOperationException
if this traversable or iterator is empty.
Full Signaturedef maxBy[B](f: (T) ⇒ B)(implicit cmp: Ordering[B]): T
-
def
min: A
[use case] Finds the smallest element.
[use case]Finds the smallest element.
- returns
the smallest element of this traversable or iterator
- Definition Classes
- TraversableOnce → GenTraversableOnce
- Exceptions thrown
UnsupportedOperationException
if this traversable or iterator is empty.
Full Signaturedef min[B >: T](implicit cmp: Ordering[B]): T
-
def
minBy[B](f: (A) ⇒ B): A
[use case] Finds the first element which yields the smallest value measured by function f.
[use case]Finds the first element which yields the smallest value measured by function f.
- B
The result type of the function f.
- f
The measuring function.
- returns
the first element of this traversable or iterator with the smallest value measured by function f.
- Definition Classes
- TraversableOnce → GenTraversableOnce
- Exceptions thrown
UnsupportedOperationException
if this traversable or iterator is empty.
Full Signaturedef minBy[B](f: (T) ⇒ B)(implicit cmp: Ordering[B]): T
-
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
-
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 stringsep
.
- Definition Classes
- TraversableOnce → GenTraversableOnce
List(1, 2, 3).mkString("|") = "1|2|3"
Example: -
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 stringend
. Inside, the string representations (w.r.t. the methodtoString
) of all elements of this traversable or iterator are separated by the stringsep
.
- Definition Classes
- TraversableOnce → GenTraversableOnce
List(1, 2, 3).mkString("(", "; ", ")") = "(1; 2; 3)"
Example: -
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
-
def
padTo(len: Int, elem: T): Iterator[T]
[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 leastlen
.
- Definition Classes
- Iterator
-
def
partition(p: (T) ⇒ Boolean): (Iterator[T], Iterator[T])
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.
-
def
patch[B >: T](from: Int, patchElems: Iterator[B], replaced: Int): Iterator[B]
Returns this iterator with patched values.
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
product: A
[use case] Multiplies up the elements of this collection.
[use case]Multiplies up the elements of this collection.
- returns
the product of all elements in this traversable or iterator of numbers of type
Int
. Instead ofInt
, any other typeT
with an implicitNumeric[T]
implementation can be used as element type of the traversable or iterator and as result type ofproduct
. Examples of such types are:Long
,Float
,Double
,BigInt
.
- Definition Classes
- TraversableOnce → GenTraversableOnce
Full Signaturedef product[B >: T](implicit num: Numeric[B]): B
-
def
reduce[A1 >: T](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.
-
def
reduceLeft[B >: T](op: (B, T) ⇒ B): B
Applies a binary operator to all elements of this traversable or iterator, going left to right.
Applies a binary operator to all elements of this traversable or iterator, going left to right.
Note: will not terminate for infinite-sized collections.
Note: might return different results for different runs, unless the underlying collection type is ordered or the operator is associative and commutative.
- B
the result type of the binary operator.
- op
the binary operator.
- returns
the result of inserting
op
between consecutive elements of this traversable or iterator, going left to right:op( op( ... op(x_1, x_2) ..., x_{n-1}), x_n)
where
x1, ..., xn
are the elements of this traversable or iterator.
- Definition Classes
- TraversableOnce
- Exceptions thrown
UnsupportedOperationException
if this traversable or iterator is empty.
-
def
reduceLeftOption[B >: T](op: (B, T) ⇒ 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-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 traversable or iterator is nonempty,None
otherwise.
- Definition Classes
- TraversableOnce → GenTraversableOnce
-
def
reduceOption[A1 >: T](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, andNone
otherwise.
- Definition Classes
- TraversableOnce → GenTraversableOnce
-
def
reduceRight[B >: T](op: (T, 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-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 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.
-
def
reduceRightOption[B >: T](op: (T, 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-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 traversable or iterator is nonempty,None
otherwise.
- Definition Classes
- TraversableOnce → GenTraversableOnce
-
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.
-
def
scanLeft[B](z: B)(op: (B, T) ⇒ B): Iterator[B]
Produces a collection containing cumulative results of applying the operator going left to right, including the initial value.
Produces a collection containing cumulative results of applying the operator going left to right, including the initial value.
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.
-
def
scanRight[B](z: B)(op: (T, B) ⇒ B): Iterator[B]
Produces a collection containing cumulative results of applying the operator going right to left.
Produces a collection containing cumulative results of applying the operator going right to left. The head of the collection is the last cumulative result.
Note: will not terminate for infinite 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
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.
Example: -
def
seq: Iterator[T]
A version of this collection with all of the operations implemented sequentially (i.e., in a single-threaded manner).
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
-
def
size: Int
The size of this traversable or iterator.
The size of this traversable or iterator.
Note: will not terminate for infinite-sized collections.
- returns
the number of elements in this traversable or iterator.
- Definition Classes
- TraversableOnce → GenTraversableOnce
-
def
slice(from: Int, until: Int): Iterator[T]
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. If negative, the slice starts at zero.
- until
the index of the first element following the slice. If negative, the slice is empty.
- returns
an iterator which advances this iterator past the first
from
elements usingdrop
, and then takesuntil - from
elements, usingtake
.
- 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
sliding[B >: T](size: Int, step: Int = 1): GroupedIterator[B]
Returns an iterator which presents a "sliding window" view of this iterator.
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. Thestep
defaults to1
.The default
GroupedIterator
can be configured to either pad a partial result to sizesize
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: (T) ⇒ Boolean): (Iterator[T], Iterator[T])
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.
-
def
sum: A
[use case] Sums up the elements of this collection.
[use case]Sums up the elements of this collection.
- returns
the sum of all elements in this traversable or iterator of numbers of type
Int
. Instead ofInt
, any other typeT
with an implicitNumeric[T]
implementation can be used as element type of the traversable or iterator and as result type ofsum
. Examples of such types are:Long
,Float
,Double
,BigInt
.
- Definition Classes
- TraversableOnce → GenTraversableOnce
Full Signaturedef sum[B >: T](implicit num: Numeric[B]): B
-
def
take(n: Int): Iterator[T]
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 the first
n
values of this iterator, or else the whole iterator, if it produces fewer thann
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.
-
def
takeWhile(p: (T) ⇒ Boolean): Iterator[T]
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.
-
def
to[Col[_]]: Col[A]
[use case] Converts this traversable or iterator into another by copying all elements.
[use case]Converts this traversable or iterator into another by copying all elements.
Note: will not terminate for infinite iterators.
- Col
The collection type to build.
- returns
a new collection containing all elements of this traversable or iterator.
- Definition Classes
- TraversableOnce → GenTraversableOnce
Full Signaturedef to[Col[_]](implicit cbf: CanBuildFrom[Nothing, T, Col[T]]): Col[T]
-
def
toArray: Array[A]
[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. An
ClassTag
must be available for the element type of this traversable or iterator.
- Definition Classes
- TraversableOnce → GenTraversableOnce
-
def
toBuffer[B >: T]: Buffer[B]
Uses the contents of this traversable or iterator to create a new mutable buffer.
Uses the contents of this traversable or iterator to create a new mutable buffer.
Note: will not terminate for infinite-sized collections.
- returns
a buffer containing all elements of this traversable or iterator.
- Definition Classes
- TraversableOnce → GenTraversableOnce
-
def
toIndexedSeq: immutable.IndexedSeq[T]
Converts this traversable or iterator to an indexed sequence.
Converts this traversable or iterator to an indexed sequence.
Note: will not terminate for infinite-sized collections.
- returns
an indexed sequence containing all elements of this traversable or iterator.
- Definition Classes
- TraversableOnce → GenTraversableOnce
-
def
toIterable: Iterable[T]
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 thisTraversableOnce
may be lazy and unevaluated (i.e. it may be an iterator which is only traversable once).Note: will not terminate for infinite-sized collections.
- returns
an
Iterable
containing all elements of this traversable or iterator.
- Definition Classes
- TraversableOnce → GenTraversableOnce
-
def
toIterator: Iterator[T]
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
-
def
toList: List[T]
Converts this traversable or iterator to a list.
Converts this traversable or iterator to a list.
Note: will not terminate for infinite-sized collections.
- returns
a list containing all elements of this traversable or iterator.
- Definition Classes
- TraversableOnce → GenTraversableOnce
-
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 of type
immutable.Map[T, U]
containing all key/value pairs of type(T, U)
of this traversable or iterator.
- Definition Classes
- TraversableOnce → GenTraversableOnce
Full Signaturedef toMap[T, U](implicit ev: <:<[T, (T, U)]): immutable.Map[T, U]
-
def
toParArray: ParArray[T]
- Implicit
- This member is added by an implicit conversion from Splitter[T] to CollectionsHaveToParArray[Splitter[T], T] performed by method CollectionsHaveToParArray in scala.collection.parallel. This conversion will take place only if an implicit value of type (Splitter[T]) ⇒ GenTraversableOnce[T] is in scope.
- Definition Classes
- CollectionsHaveToParArray
-
def
toSeq: Seq[T]
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 thisTraversableOnce
may be lazy and unevaluated.Note: will not terminate for infinite-sized collections.
- returns
a sequence containing all elements of this traversable or iterator.
- Definition Classes
- TraversableOnce → GenTraversableOnce
-
def
toSet[B >: T]: immutable.Set[B]
Converts this traversable or iterator to a set.
Converts this traversable or iterator to a set.
Note: will not terminate for infinite-sized collections.
- returns
a set containing all elements of this traversable or iterator.
- Definition Classes
- TraversableOnce → GenTraversableOnce
-
def
toStream: immutable.Stream[T]
Converts this traversable or iterator to a stream.
Converts this traversable or iterator to a stream.
- returns
a stream containing all elements of this traversable or iterator.
- Definition Classes
- Iterator → GenTraversableOnce
-
def
toString(): String
Converts this iterator to a string.
-
def
toTraversable: Traversable[T]
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
-
def
toVector: Vector[T]
Converts this traversable or iterator to a Vector.
Converts this traversable or iterator to a Vector.
Note: will not terminate for infinite-sized collections.
- returns
a vector containing all elements of this traversable or iterator.
- Definition Classes
- TraversableOnce → GenTraversableOnce
-
def
withFilter(p: (T) ⇒ Boolean): Iterator[T]
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 asfilter
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: Iterator[B]): Iterator[(T, 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 andthat
.
- 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
zipAll[B](that: Iterator[B], thisElem: T, thatElem: B): Iterator[(T, 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 thanthat
- thatElem
element
thatElem
is used to fill up the resulting iterator ifthat
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 andthat
. If this iterator is shorter thanthat
,thisElem
values are used to pad the result. Ifthat
is shorter than this iterator,thatElem
values are used to pad the result.
- Definition Classes
- Iterator
-
def
zipWithIndex: Iterator[(T, Int)]
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.
Shadowed Implicit Value Members
-
def
filter(p: (T) ⇒ Boolean): TraversableOnce[T]
- Implicit
- This member is added by an implicit conversion from Splitter[T] to MonadOps[T] performed by method MonadOps in scala.collection.TraversableOnce.
- Shadowing
- This implicitly inherited member is shadowed by one or more members in this class.
To access this member you can use a type ascription:(splitter: MonadOps[T]).filter(p)
- Definition Classes
- MonadOps
-
def
flatMap[B](f: (T) ⇒ GenTraversableOnce[B]): TraversableOnce[B]
- Implicit
- This member is added by an implicit conversion from Splitter[T] to MonadOps[T] performed by method MonadOps in scala.collection.TraversableOnce.
- Shadowing
- This implicitly inherited member is shadowed by one or more members in this class.
To access this member you can use a type ascription:(splitter: MonadOps[T]).flatMap(f)
- Definition Classes
- MonadOps
-
def
map[B](f: (T) ⇒ B): TraversableOnce[B]
- Implicit
- This member is added by an implicit conversion from Splitter[T] to MonadOps[T] performed by method MonadOps in scala.collection.TraversableOnce.
- Shadowing
- This implicitly inherited member is shadowed by one or more members in this class.
To access this member you can use a type ascription:(splitter: MonadOps[T]).map(f)
- Definition Classes
- MonadOps
-
def
withFilter(p: (T) ⇒ Boolean): Iterator[T]
- Implicit
- This member is added by an implicit conversion from Splitter[T] to MonadOps[T] performed by method MonadOps in scala.collection.TraversableOnce.
- Shadowing
- This implicitly inherited member is shadowed by one or more members in this class.
To access this member you can use a type ascription:(splitter: MonadOps[T]).withFilter(p)
- Definition Classes
- MonadOps
Deprecated Value Members
-
def
/:[B](z: B)(op: (B, T) ⇒ 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 forfoldLeft
;z /: xs
is the same asxs foldLeft z
.Examples:
Note that the folding function used to compute b is equivalent to that used to compute c.
scala> val a = List(1,2,3,4) a: List[Int] = List(1, 2, 3, 4) scala> val b = (5 /: a)(_+_) b: Int = 15 scala> val c = (5 /: a)((x,y) => x + y) c: Int = 15
Note: will not terminate for infinite-sized collections.
Note: might return different results for different runs, unless the underlying collection type is ordered or the operator is associative and commutative.
- B
the result type of the binary operator.
- z
the start value.
- op
the binary operator.
- returns
the result of inserting
op
between consecutive elements of this traversable or iterator, going left to right with the start valuez
on the left:op(...op(op(z, x_1), x_2), ..., x_n)
where
x1, ..., xn
are the elements of this traversable or iterator.
- Definition Classes
- TraversableOnce → GenTraversableOnce
- Annotations
- @deprecated
- Deprecated
(Since version 2.12.10) Use foldLeft instead of /:
-
def
:\[B](z: B)(op: (T, 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 forfoldRight
;xs :\ z
is the same asxs foldRight z
.Note: will not terminate for infinite-sized collections.
Note: might return different results for different runs, unless the underlying collection type is ordered or the operator is associative and commutative.
Examples:
Note that the folding function used to compute b is equivalent to that used to compute c.
scala> val a = List(1,2,3,4) a: List[Int] = List(1, 2, 3, 4) scala> val b = (a :\ 5)(_+_) b: Int = 15 scala> val c = (a :\ 5)((x,y) => x + y) c: Int = 15
- B
the result type of the binary operator.
- z
the start value
- op
the binary operator
- returns
the result of inserting
op
between consecutive elements of this traversable or iterator, 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 traversable or iterator.
- Definition Classes
- TraversableOnce → GenTraversableOnce
- Annotations
- @deprecated
- Deprecated
(Since version 2.12.10) Use foldRight instead of :\
This is the documentation for the Scala standard library.
Package structure
The scala package contains core types like
Int
,Float
,Array
orOption
which are accessible in all Scala compilation units without explicit qualification or imports.Notable packages include:
scala.collection
and its sub-packages contain Scala's collections frameworkscala.collection.immutable
- Immutable, sequential data-structures such asVector
,List
,Range
,HashMap
orHashSet
scala.collection.mutable
- Mutable, sequential data-structures such asArrayBuffer
,StringBuilder
,HashMap
orHashSet
scala.collection.concurrent
- Mutable, concurrent data-structures such asTrieMap
scala.collection.parallel.immutable
- Immutable, parallel data-structures such asParVector
,ParRange
,ParHashMap
orParHashSet
scala.collection.parallel.mutable
- Mutable, parallel data-structures such asParArray
,ParHashMap
,ParTrieMap
orParHashSet
scala.concurrent
- Primitives for concurrent programming such asFutures
andPromises
scala.io
- Input and output operationsscala.math
- Basic math functions and additional numeric types likeBigInt
andBigDecimal
scala.sys
- Interaction with other processes and the operating systemscala.util.matching
- Regular expressionsOther packages exist. See the complete list on the right.
Additional parts of the standard library are shipped as separate libraries. These include:
scala.reflect
- Scala's reflection API (scala-reflect.jar)scala.xml
- XML parsing, manipulation, and serialization (scala-xml.jar)scala.swing
- A convenient wrapper around Java's GUI framework called Swing (scala-swing.jar)scala.util.parsing
- Parser combinators (scala-parser-combinators.jar)Automatic imports
Identifiers in the scala package and the
scala.Predef
object are always in scope by default.Some of these identifiers are type aliases provided as shortcuts to commonly used classes. For example,
List
is an alias forscala.collection.immutable.List
.Other aliases refer to classes provided by the underlying platform. For example, on the JVM,
String
is an alias forjava.lang.String
.