trait BufferedIterator[+A] extends Iterator[A]
Buffered iterators are iterators which provide a method head
that inspects the next element without discarding it.
- Source
- BufferedIterator.scala
- Alphabetic
- By Inheritance
- BufferedIterator
- Iterator
- IterableOnceOps
- IterableOnce
- AnyRef
- Any
- by iterableOnceExtensionMethods
- by any2stringadd
- by StringFormat
- by Ensuring
- by ArrowAssoc
- Hide All
- Show All
- Public
- Protected
Type Members
- class GroupedIterator[B >: A] extends AbstractIterator[immutable.Seq[B]]
A flexible iterator for transforming an
Iterator[A]
into anIterator[Seq[A]]
, with configurable sequence size, step, and strategy for dealing with remainder elements which don't fit evenly into the last group.A flexible iterator for transforming an
Iterator[A]
into anIterator[Seq[A]]
, with configurable sequence size, step, and strategy for dealing with remainder elements which don't fit evenly into the last group.A
GroupedIterator
is yielded bygrouped
and bysliding
, where thestep
may differ from the groupsize
.- Definition Classes
- Iterator
Abstract Value Members
- abstract def hasNext: Boolean
Check if there is a next element available.
Check if there is a next element available.
- returns
true
if there is a next element,false
otherwise
- Definition Classes
- Iterator
- Note
Reuse: The iterator remains valid for further use whatever result is returned.
- abstract def head: A
Returns next element of iterator without advancing beyond it.
- abstract def next(): A
Return the next element and advance the iterator.
Return the next element and advance the iterator.
- returns
the next element.
- Definition Classes
- Iterator
- Annotations
- @throws(cause = scala.this.throws.<init>$default$1[NoSuchElementException])
- 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.
Concrete Value Members
- final def !=(arg0: Any): Boolean
Test two objects for inequality.
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 andnull
.Equivalent to
x.hashCode
except for boxed numeric types andnull
. 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. Fornull
returns a hashcode wherenull.hashCode
throws aNullPointerException
.- returns
a hash value consistent with ==
- Definition Classes
- AnyRef → Any
- def +(other: String): String
- Implicit
- This member is added by an implicit conversion from BufferedIterator[A] toany2stringadd[BufferedIterator[A]] performed by method any2stringadd in scala.Predef.
- Definition Classes
- any2stringadd
- final def ++[B >: A](xs: => IterableOnce[B]): Iterator[B]
- def ->[B](y: B): (BufferedIterator[A], B)
- Implicit
- This member is added by an implicit conversion from BufferedIterator[A] toArrowAssoc[BufferedIterator[A]] performed by method ArrowAssoc in scala.Predef.
- Definition Classes
- ArrowAssoc
- Annotations
- @inline()
- final def ==(arg0: Any): Boolean
The expression
x == that
is equivalent toif (x eq null) that eq null else x.equals(that)
.The expression
x == that
is equivalent toif (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): b.type
Appends all elements of this iterator to a string builder.
Appends all elements of this iterator to a string builder. The written text consists of the string representations (w.r.t. the method
toString
) of all elements of this 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
- IterableOnceOps
- Annotations
- @inline()
- final def addString(b: mutable.StringBuilder, sep: String): b.type
Appends all elements of this iterator to a string builder using a separator string.
Appends all elements of this 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 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
- IterableOnceOps
- Annotations
- @inline()
- def addString(b: mutable.StringBuilder, start: String, sep: String, end: String): b.type
Appends all elements of this iterator to a string builder using start, end, and separator strings.
Appends all elements of this 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 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
- IterableOnceOps
- final def asInstanceOf[T0]: T0
Forces the compiler to treat the receiver object as having type
T0
, even though doing so may violate type safety.Forces the compiler to treat the receiver object as having type
T0
, even though doing so may violate type safety.This method is useful when you believe you have type information the compiler doesn't, and it also isn't possible to check the type at runtime. In such situations, skipping type safety is the only option.
It is platform dependent whether
asInstanceOf
has any effect at runtime. It might do a runtime type test on the erasure ofT0
, insert a conversion (such as boxing/unboxing), fill in a default value, or do nothing at all.In particular,
asInstanceOf
is not a type test. It does **not** mean:this match { case x: T0 => x case _ => throw ClassCastException("...")
Use pattern matching or isInstanceOf for type testing instead.
Situations where
asInstanceOf
is useful:- when flow analysis fails to deduce
T0
automatically - when down-casting a type parameter or an abstract type member (which cannot be checked at runtime due to type erasure) If there is any doubt and you are able to type test instead, you should do so.
Be careful of using
asInstanceOf
whenT0
is a primitive type. WhenT0
is primitive,asInstanceOf
may insert a conversion instead of a type test. If your intent is to convert, use atoT
method (x.toChar
,x.toByte
, etc.).- returns
the receiver object.
- Definition Classes
- Any
- Exceptions thrown
ClassCastException
if the receiver is not an instance of the erasure ofT0
, if that can be checked on this platform
- when flow analysis fails to deduce
- def buffered: BufferedIterator.this.type
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
- BufferedIterator → 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.
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.
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
- def collectFirst[B](pf: PartialFunction[A, B]): Option[B]
Finds the first element of the iterator for which the given partial function is defined, and applies the partial function to it.
Finds the first element of the iterator for which the given partial function is defined, and applies the partial function to it.
Note: may not terminate for infinite iterators.
Note: might return different results for different runs, unless the underlying collection type is ordered.
- pf
the partial function
- returns
an option value containing pf applied to the first value for which it is defined, or
None
if none exists.
- Definition Classes
- IterableOnceOps
Seq("a", 1, 5L).collectFirst({ case x: Int => x*10 }) = Some(10)
Example: - 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.
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.
Copy elements to an array, returning the number of elements written.
Fills the given array
xs
starting at indexstart
with at mostlen
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
- IterableOnceOps
- 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): Int
Copies elements to an array, returning the number of elements written.
Copies elements to an array, returning the number of elements written.
Fills the given array
xs
starting at indexstart
with values 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.
- 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
- Definition Classes
- IterableOnceOps
- Annotations
- @deprecatedOverriding()
- 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]): Int
Copies elements to an array, returning the number of elements written.
Copies elements to an array, returning the number of elements written.
Fills the given array
xs
starting at indexstart
with values 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.
- B
the type of the elements of the array.
- xs
the array to fill.
- returns
the number of elements written to the array
- Definition Classes
- IterableOnceOps
- Annotations
- @deprecatedOverriding()
- Note
Reuse: After calling this method, one should discard the iterator it was called on. Using it is undefined and subject to change.
- 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.
Tests whether every element of this collection's iterator relates to the corresponding element of another collection by satisfying a test predicate.
Note: will not terminate for infinite-sized collections.
- 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 iterator which satisfy a predicate.
Counts the number of elements in the iterator which satisfy a predicate.
Note: will not terminate for infinite-sized collections.
- 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.
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 functionf
.Builds a new iterator from this one without any duplicated elements as determined by
==
after applying the transforming functionf
.- 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 the first
n
ones.Selects all elements except the 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
- Iterator → IterableOnceOps
- def dropWhile(p: (A) => Boolean): Iterator[A]
Selects all elements except the longest prefix that satisfies a predicate.
Selects all elements except the longest prefix that satisfies a predicate.
The matching prefix starts with the first element of this iterator, and the element following the prefix is the first element that does not satisfy the predicate. The matching prefix may be empty, so that this method returns the entire iterator.
Example:
scala> List(1, 2, 3, 100, 4).dropWhile(n => n < 10) val res0: List[Int] = List(100, 4) scala> List(1, 2, 3, 100, 4).dropWhile(n => n == 0) val res1: List[Int] = List(1, 2, 3, 100, 4)
Use span to obtain both the prefix and suffix. Use filterNot to drop all elements that satisfy the 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
- def duplicate: (Iterator[A], Iterator[A])
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 ensuring(cond: (BufferedIterator[A]) => Boolean, msg: => Any): BufferedIterator[A]
- Implicit
- This member is added by an implicit conversion from BufferedIterator[A] toEnsuring[BufferedIterator[A]] performed by method Ensuring in scala.Predef.
- Definition Classes
- Ensuring
- def ensuring(cond: (BufferedIterator[A]) => Boolean): BufferedIterator[A]
- Implicit
- This member is added by an implicit conversion from BufferedIterator[A] toEnsuring[BufferedIterator[A]] performed by method Ensuring in scala.Predef.
- Definition Classes
- Ensuring
- def ensuring(cond: Boolean, msg: => Any): BufferedIterator[A]
- Implicit
- This member is added by an implicit conversion from BufferedIterator[A] toEnsuring[BufferedIterator[A]] performed by method Ensuring in scala.Predef.
- Definition Classes
- Ensuring
- def ensuring(cond: Boolean): BufferedIterator[A]
- Implicit
- This member is added by an implicit conversion from BufferedIterator[A] toEnsuring[BufferedIterator[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
).Tests whether the argument (
that
) is a reference to the receiver object (this
).The
eq
method implements an equivalence relation on non-null instances ofAnyRef
, and has three additional properties:- It is consistent: for any non-null instances
x
andy
of typeAnyRef
, multiple invocations ofx.eq(y)
consistently returnstrue
or consistently returnsfalse
. - For any non-null instance
x
of typeAnyRef
,x.eq(null)
andnull.eq(x)
returnsfalse
. null.eq(null)
returnstrue
.
When overriding the
equals
orhashCode
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
- It is consistent: for any non-null instances
- def equals(arg0: AnyRef): Boolean
The equality method for reference types.
- def exists(p: (A) => Boolean): Boolean
Tests whether a predicate holds for at least one element of this iterator.
Tests whether a predicate holds for at least one element of this iterator.
Note: may not terminate for infinite iterators.
- p
the predicate used to test elements.
- returns
true
if the given predicatep
is satisfied by at least one element of this iterator, otherwisefalse
- Definition Classes
- IterableOnceOps
- def filter(p: (A) => Boolean): Iterator[A]
Selects all elements of this iterator which satisfy a predicate.
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.
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.
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 betweenfinalize
and non-local returns and exceptions, are all platform dependent.- Attributes
- protected[lang]
- Definition Classes
- AnyRef
- Annotations
- @throws(classOf[java.lang.Throwable])
- Note
not specified by SLS as a member of AnyRef
- def find(p: (A) => Boolean): Option[A]
Finds the first element of the iterator satisfying a predicate, if any.
Finds the first element of the iterator satisfying a predicate, if any.
Note: may not terminate for infinite iterators.
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 iterator 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.
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
- def flatten[B](implicit ev: (A) => IterableOnce[B]): Iterator[B]
Converts this iterator of iterable collections into a iterator formed by the elements of these iterable collections.
Converts this iterator of iterable collections into a iterator formed by the elements of these iterable 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 iterable collection.
- returns
a new iterator resulting from concatenating all element iterators.
- Definition Classes
- Iterator → IterableOnceOps
- def fold[A1 >: A](z: A1)(op: (A1, A1) => A1): A1
Applies the given binary operator
op
to the given initial valuez
and all elements of this iterator.Applies the given binary operator
op
to the given initial valuez
and all elements of this iterator.For each application of the operator, each operand is either an element of this iterator, the initial value, or another such application of the operator.
The order of applications of the operator is unspecified and may be nondeterministic. Each element appears exactly once in the computation. The initial value may be used an arbitrary number of times, but at least once.
If this collection is ordered, then for any application of the operator, the element(s) appearing in the left operand will precede those in the right.
Note: might return different results for different runs, unless either of the following conditions is met: (1) the operator is associative, and the underlying collection type is ordered; or (2) the operator is associative and commutative. In either case, it is also necessary that the initial value be a neutral value for the operator, e.g.
Nil
forList
concatenation or1
for multiplication.The default implementation in
IterableOnce
is equivalent tofoldLeft
but may be overridden for more efficient traversal orders.Note: will not terminate for infinite-sized collections.
- A1
The type parameter for the binary operator, a supertype of
A
.- z
An initial value; may be used an arbitrary number of times in the computation of the result; must be a neutral value for
op
for the result to always be the same across runs.- op
A binary operator; must be associative for the result to always be the same across runs.
- returns
The result of applying
op
between all the elements andz
, orz
if this iterator is empty.
- Definition Classes
- IterableOnceOps
- def foldLeft[B](z: B)(op: (B, A) => B): B
Applies the given binary operator
op
to the given initial valuez
and all elements of this iterator, going left to right.Applies the given binary operator
op
to the given initial valuez
and all elements of this iterator, going left to right. Returns the initial value if this iterator is empty."Going left to right" only makes sense if this collection is ordered: then if
x1
,x2
, ...,xn
are the elements of this iterator, the result isop( op( ... op( op(z, x1), x2) ... ), xn)
.If this collection is not ordered, then for each application of the operator, each right operand is an element. In addition, the leftmost operand is the initial value, and each other left operand is itself an application of the operator. The elements of this iterator and the initial value all appear exactly once in the computation.
Note: might return different results for different runs, unless the underlying collection type is ordered.
Note: will not terminate for infinite-sized collections.
- B
The result type of the binary operator.
- z
An initial value.
- op
A binary operator.
- returns
The result of applying
op
toz
and all elements of this iterator, going left to right. Returnsz
if this iterator is empty.
- Definition Classes
- IterableOnceOps
- def foldRight[B](z: B)(op: (A, B) => B): B
Applies the given binary operator
op
to all elements of this iterator and the given initial valuez
, going right to left.Applies the given binary operator
op
to all elements of this iterator and the given initial valuez
, going right to left. Returns the initial value if this iterator is empty."Going right to left" only makes sense if this collection is ordered: then if
x1
,x2
, ...,xn
are the elements of this iterator, the result isop(x1, op(x2, op( ... op(xn, z) ... )))
.If this collection is not ordered, then for each application of the operator, each left operand is an element. In addition, the rightmost operand is the initial value, and each other right operand is itself an application of the operator. The elements of this iterator and the initial value all appear exactly once in the computation.
Note: might return different results for different runs, unless the underlying collection type is ordered.
Note: will not terminate for infinite-sized collections.
- B
The result type of the binary operator.
- z
An initial value.
- op
A binary operator.
- returns
The result of applying
op
to all elements of this iterator andz
, going right to left. Returnsz
if this iterator is empty.
- Definition Classes
- IterableOnceOps
- def forall(p: (A) => Boolean): Boolean
Tests whether a predicate holds for all elements of this iterator.
Tests whether a predicate holds for all elements of this iterator.
Note: may not terminate for infinite iterators.
- p
the predicate used to test elements.
- returns
true
if this iterator is empty or the given predicatep
holds for all elements of this iterator, otherwisefalse
.
- Definition Classes
- IterableOnceOps
- def foreach[U](f: (A) => U): Unit
Applies
f
to each element for its side effects.Applies
f
to each element for its side effects. Note:U
parameter needed to help scalac's type inference.- Definition Classes
- IterableOnceOps
- final def getClass(): Class[_ <: AnyRef]
Returns the runtime class representation of the object.
- def grouped[B >: A](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 hashCode(): Int
The hashCode method for reference types.
- def headOption: Option[A]
Returns an option of the next element of an iterator without advancing beyond it.
Returns an option of the next element of an iterator without advancing beyond it.
- returns
the next element of this iterator if it has a next element
None
if it does not
- 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.
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.
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.
Tests whether the iterator is empty.
Note: The default implementation creates and discards an iterator.
Note: Implementations in subclasses that are not repeatedly iterable 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()
- final def isInstanceOf[T0]: Boolean
Test whether the dynamic type of the receiver object has the same erasure as
T0
.Test whether the dynamic type of the receiver object has the same erasure as
T0
.Depending on what
T0
is, the test is done in one of the below ways:T0
is a non-parameterized class type, e.g.BigDecimal
: this method returnstrue
if the value of the receiver object is aBigDecimal
or a subtype ofBigDecimal
.T0
is a parameterized class type, e.g.List[Int]
: this method returnstrue
if the value of the receiver object is someList[X]
for anyX
. For example,List(1, 2, 3).isInstanceOf[List[String]]
will return true.T0
is some singleton typex.type
or literalx
: this method returnsthis.eq(x)
. For example,x.isInstanceOf[1]
is equivalent tox.eq(1)
T0
is an intersectionX with Y
orX & Y: this method is equivalent to
x.isInstanceOf[X] && x.isInstanceOf[Y]T0
is a unionX | Y
: this method is equivalent tox.isInstanceOf[X] || x.isInstanceOf[Y]
T0
is a type parameter or an abstract type member: this method is equivalent toisInstanceOf[U]
whereU
isT0
's upper bound,Any
ifT0
is unbounded. For example,x.isInstanceOf[A]
whereA
is an unbounded type parameter will return true for any value ofx
.
This is exactly equivalent to the type pattern
_: T0
- returns
true
if the receiver object is an instance of erasure of typeT0
;false
otherwise.
- Definition Classes
- Any
- Note
due to the unexpectedness of
List(1, 2, 3).isInstanceOf[List[String]]
returning true andx.isInstanceOf[A]
whereA
is a type parameter or abstract member returning true, these forms issue a warning.
- def isTraversableAgain: Boolean
Tests whether this iterator can be repeatedly traversed.
Tests whether this iterator 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]
An scala.collection.Iterator over the elements of this iterator.
An scala.collection.Iterator over the elements of this iterator.
If an
IterableOnce
object is in fact an scala.collection.Iterator, this method always returns itself, in its current state, but if it is an scala.collection.Iterable, this method always returns a new scala.collection.Iterator.- Definition Classes
- Iterator → IterableOnce
- Annotations
- @inline()
- def knownSize: Int
The number of elements in this iterator, if it can be cheaply computed, -1 otherwise.
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
- 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.
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
- def max[B >: A](implicit ord: math.Ordering[B]): A
Finds the largest element.
Finds the largest element.
Note: will not terminate for infinite-sized collections.
- B
The type over which the ordering is defined.
- ord
An ordering to be used for comparing elements.
- returns
the largest element of this iterator with respect to the ordering
ord
.
- Definition Classes
- IterableOnceOps
- Exceptions thrown
UnsupportedOperationException
if this iterator is empty.
- def maxBy[B](f: (A) => B)(implicit ord: math.Ordering[B]): A
Finds the first element which yields the largest value measured by function
f
.Finds the first element which yields the largest value measured by function
f
.Note: will not terminate for infinite-sized collections.
- B
The result type of the function
f
.- f
The measuring function.
- returns
the first element of this iterator with the largest value measured by function
f
with respect to the orderingcmp
.
- Definition Classes
- IterableOnceOps
- Exceptions thrown
UnsupportedOperationException
if this iterator is empty.
- def maxByOption[B](f: (A) => B)(implicit ord: math.Ordering[B]): Option[A]
Finds the first element which yields the largest value measured by function
f
.Finds the first element which yields the largest value measured by function
f
.Note: will not terminate for infinite-sized collections.
- B
The result type of the function
f
.- f
The measuring function.
- returns
an option value containing the first element of this iterator with the largest value measured by function
f
with respect to the orderingcmp
.
- Definition Classes
- IterableOnceOps
- def maxOption[B >: A](implicit ord: math.Ordering[B]): Option[A]
Finds the largest element.
Finds the largest element.
Note: will not terminate for infinite-sized collections.
- 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 iterator with respect to the ordering
ord
.
- Definition Classes
- IterableOnceOps
- def min[B >: A](implicit ord: math.Ordering[B]): A
Finds the smallest element.
Finds the smallest element.
Note: will not terminate for infinite-sized collections.
- B
The type over which the ordering is defined.
- ord
An ordering to be used for comparing elements.
- returns
the smallest element of this iterator with respect to the ordering
ord
.
- Definition Classes
- IterableOnceOps
- Exceptions thrown
UnsupportedOperationException
if this iterator is empty.
- def minBy[B](f: (A) => B)(implicit ord: math.Ordering[B]): A
Finds the first element which yields the smallest value measured by function
f
.Finds the first element which yields the smallest value measured by function
f
.Note: will not terminate for infinite-sized collections.
- B
The result type of the function
f
.- f
The measuring function.
- returns
the first element of this iterator with the smallest value measured by function
f
with respect to the orderingcmp
.
- Definition Classes
- IterableOnceOps
- Exceptions thrown
UnsupportedOperationException
if this iterator is empty.
- def minByOption[B](f: (A) => B)(implicit ord: math.Ordering[B]): Option[A]
Finds the first element which yields the smallest value measured by function
f
.Finds the first element which yields the smallest value measured by function
f
.Note: will not terminate for infinite-sized collections.
- B
The result type of the function
f
.- f
The measuring function.
- returns
an option value containing the first element of this iterator with the smallest value measured by function
f
with respect to the orderingcmp
.
- Definition Classes
- IterableOnceOps
- def minOption[B >: A](implicit ord: math.Ordering[B]): Option[A]
Finds the smallest element.
Finds the smallest element.
Note: will not terminate for infinite-sized collections.
- 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 iterator with respect to the ordering
ord
.
- Definition Classes
- IterableOnceOps
- final def mkString: String
Displays all elements of this iterator in a string.
Displays all elements of this iterator in a string.
Delegates to addString, which can be overridden.
- returns
a string representation of this iterator. In the resulting string the string representations (w.r.t. the method
toString
) of all elements of this iterator follow each other without any separator string.
- Definition Classes
- IterableOnceOps
- Annotations
- @inline()
- final def mkString(sep: String): String
Displays all elements of this iterator in a string using a separator string.
Displays all elements of this iterator in a string using a separator string.
Delegates to addString, which can be overridden.
- sep
the separator string.
- returns
a string representation of this iterator. In the resulting string the string representations (w.r.t. the method
toString
) of all elements of this iterator are separated by the stringsep
.
- Definition Classes
- IterableOnceOps
- Annotations
- @inline()
List(1, 2, 3).mkString("|") = "1|2|3"
Example: - final def mkString(start: String, sep: String, end: String): String
Displays all elements of this iterator in a string using start, end, and separator strings.
Displays all elements of this iterator 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 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 iterator are separated by the stringsep
.
- Definition Classes
- IterableOnceOps
List(1, 2, 3).mkString("(", "; ", ")") = "(1; 2; 3)"
Example: - final def ne(arg0: AnyRef): Boolean
Equivalent to
!(this eq that)
.Equivalent to
!(this eq that)
.- returns
true
if the argument is not a reference to the receiver object;false
otherwise.
- Definition Classes
- AnyRef
- def nextOption(): Option[A]
Wraps the value of
next()
in an option.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 iterator is not empty.
Tests whether the iterator is not empty.
- returns
true
if the iterator contains at least one element,false
otherwise.
- Definition Classes
- IterableOnceOps
- Annotations
- @deprecatedOverriding()
- final def notify(): Unit
Wakes up a single thread that is waiting on the receiver object's monitor.
Wakes up a single thread that is waiting on the receiver object's monitor.
- Definition Classes
- AnyRef
- 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.
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.
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.
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.
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[B >: A](implicit num: math.Numeric[B]): B
Multiplies together the elements of this collection.
Multiplies together the elements of this collection.
The default implementation uses
reduce
for a known non-empty collection,foldLeft
otherwise.Note: will not terminate for infinite-sized collections.
- 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 iterator with respect to the
*
operator innum
.
- Definition Classes
- IterableOnceOps
- def reduce[B >: A](op: (B, B) => B): B
Applies the given binary operator
op
to all elements of this iterator.Applies the given binary operator
op
to all elements of this iterator.For each application of the operator, each operand is either an element of this iterator or another such application of the operator. The order of applications of the operator is unspecified and may be nondeterministic. Each element appears exactly once in the computation.
If this collection is ordered, then for any application of the operator, the element(s) appearing in the left operand will precede those in the right.
Note: might return different results for different runs, unless either of the following conditions is met: (1) the operator is associative, and the underlying collection type is ordered; or (2) the operator is associative and commutative.
Note: will not terminate for infinite-sized collections.
- B
The type parameter for the binary operator, a supertype of
A
.- op
A binary operator; must be associative for the result to always be the same across runs.
- returns
The result of applying
op
between all the elements if the iterator is nonempty.
- Definition Classes
- IterableOnceOps
- Exceptions thrown
UnsupportedOperationException
if this iterator is empty.
- def reduceLeft[B >: A](op: (B, A) => B): B
Applies the given binary operator
op
to all elements of this iterator, going left to right.Applies the given binary operator
op
to all elements of this iterator, going left to right."Going left to right" only makes sense if this collection is ordered: then if
x1
,x2
, ...,xn
are the elements of this iterator, the result isop( op( op( ... op(x1, x2) ... ), xn-1), xn)
.If this collection is not ordered, then for each application of the operator, each right operand is an element. In addition, the leftmost operand is the first element of this iterator and each other left operand is itself an application of the operator. Each element appears exactly once in the computation.
Note: might return different results for different runs, unless the underlying collection type is ordered or the operator is associative and commutative.
Note: will not terminate for infinite-sized collections.
- B
The result type of the binary operator, a supertype of
A
.- op
A binary operator.
- returns
The result of applying
op
to all elements of this iterator, going left to right.
- Definition Classes
- IterableOnceOps
- Exceptions thrown
UnsupportedOperationException
if this iterator is empty.
- def reduceLeftOption[B >: A](op: (B, A) => B): Option[B]
If this iterator is nonempty, reduces it with the given binary operator
op
, going left to right.If this iterator is nonempty, reduces it with the given binary operator
op
, going left to right.The behavior is the same as reduceLeft except that the value is
None
if the iterator is empty. Each element appears exactly once in the computation.Note: might return different results for different runs, unless the underlying collection type is ordered or the operator is associative and commutative.
Note: will not terminate for infinite-sized collections.
- B
The result type of the binary operator, a supertype of
A
.- op
A binary operator.
- returns
The result of reducing this iterator with
op
going left to right if the iterator is nonempty, inside aSome
, andNone
otherwise.
- Definition Classes
- IterableOnceOps
- def reduceOption[B >: A](op: (B, B) => B): Option[B]
If this iterator is nonempty, reduces it with the given binary operator
op
.If this iterator is nonempty, reduces it with the given binary operator
op
.The behavior is the same as reduce except that the value is
None
if the iterator is empty. The order of applications of the operator is unspecified and may be nondeterministic. Each element appears exactly once in the computation.Note: might return different results for different runs, unless either of the following conditions is met: (1) the operator is associative, and the underlying collection type is ordered; or (2) the operator is associative and commutative.
Note: will not terminate for infinite-sized collections.
- B
A type parameter for the binary operator, a supertype of
A
.- op
A binary operator; must be associative for the result to always be the same across runs.
- returns
The result of reducing this iterator with
op
if the iterator is nonempty, inside aSome
, andNone
otherwise.
- Definition Classes
- IterableOnceOps
- def reduceRight[B >: A](op: (A, B) => B): B
Applies the given binary operator
op
to all elements of this iterator, going right to left.Applies the given binary operator
op
to all elements of this iterator, going right to left."Going right to left" only makes sense if this collection is ordered: then if
x1
,x2
, ...,xn
are the elements of this iterator, the result isop(x1, op(x2, op( ... op(xn-1, xn) ... )))
.If this collection is not ordered, then for each application of the operator, each left operand is an element. In addition, the rightmost operand is the last element of this iterator and each other right operand is itself an application of the operator. Each element appears exactly once in the computation.
Note: might return different results for different runs, unless the underlying collection type is ordered or the operator is associative and commutative.
Note: will not terminate for infinite-sized collections.
- B
The result type of the binary operator, a supertype of
A
.- op
A binary operator.
- returns
The result of applying
op
to all elements of this iterator, going right to left.
- Definition Classes
- IterableOnceOps
- Exceptions thrown
UnsupportedOperationException
if this iterator is empty.
- def reduceRightOption[B >: A](op: (A, B) => B): Option[B]
If this iterator is nonempty, reduces it with the given binary operator
op
, going right to left.If this iterator is nonempty, reduces it with the given binary operator
op
, going right to left.The behavior is the same as reduceRight except that the value is
None
if the iterator is empty. Each element appears exactly once in the computation.Note: might return different results for different runs, unless the underlying collection type is ordered or the operator is associative and commutative.
Note: will not terminate for infinite-sized collections.
- B
The result type of the binary operator, a supertype of
A
.- op
A binary operator.
- returns
The result of reducing this iterator with
op
going right to left if the iterator is nonempty, inside aSome
, andNone
otherwise.
- Definition Classes
- IterableOnceOps
- def reversed: Iterable[A]
- Attributes
- protected
- Definition Classes
- IterableOnceOps
- def sameElements[B >: A](that: IterableOnce[B]): Boolean
Checks whether corresponding elements of the given iterable collection compare equal (with respect to
==
) to elements of this iterator.Checks whether corresponding elements of the given iterable collection compare equal (with respect to
==
) to elements of this iterator.- B
the type of the elements of collection
that
.- that
the collection to compare
- returns
true
if both collections contain equal elements in the same order,false
otherwise. <invalid inheritdoc annotation>
- 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.
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
- def size: Int
The size of this iterator.
The size of this iterator.
Note: will not terminate for infinite-sized collections.
- returns
the number of elements in this iterator.
- Definition Classes
- IterableOnceOps
- def slice(from: Int, until: Int): Iterator[A]
Selects an interval of elements.
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
- Iterator → IterableOnceOps
- def sliceIterator(from: Int, until: Int): Iterator[A]
Creates an optionally bounded slice, unbounded if
until
is negative.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.
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 returned
GroupedIterator
can be configured to either pad a partial result to sizesize
or suppress the partial result entirely.Example usages:
// Returns List(ArraySeq(1, 2, 3), ArraySeq(2, 3, 4), ArraySeq(3, 4, 5)) (1 to 5).iterator.sliding(3).toList // Returns List(ArraySeq(1, 2, 3, 4), ArraySeq(4, 5)) (1 to 5).iterator.sliding(4, 3).toList // Returns List(ArraySeq(1, 2, 3, 4)) (1 to 5).iterator.sliding(4, 3).withPartial(false).toList // Returns List(ArraySeq(1, 2, 3, 4), ArraySeq(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
- size
the number of elements per group
- step
the distance between the first elements of successive groups
- returns
A
GroupedIterator
producingSeq[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.
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 predicatep
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 iterator into a prefix/suffix pair at a given position.
Splits this iterator 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 iterators consisting of the first
n
elements of this iterator, and the other elements.
- Definition Classes
- IterableOnceOps
- def stepper[S <: Stepper[_]](implicit shape: StepperShape[A, S]): S
Returns a scala.collection.Stepper for the elements of this collection.
Returns a scala.collection.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 scala.collection.StepperShape parameter defines the resulting Stepper type according to the element type of this collection.
- For collections of
Int
,Short
,Byte
orChar
, an scala.collection.IntStepper is returned - For collections of
Double
orFloat
, a scala.collection.DoubleStepper is returned - For collections of
Long
a scala.collection.LongStepper is returned - For any other element type, an scala.collection.AnyStepper is returned
Note that this method is overridden in subclasses and the return type is refined to
S with EfficientSplit
, for example scala.collection.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
- For collections of
- def sum[B >: A](implicit num: math.Numeric[B]): B
Sums the elements of this collection.
Sums the elements of this collection.
The default implementation uses
reduce
for a known non-empty collection,foldLeft
otherwise.Note: will not terminate for infinite-sized collections.
- 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 iterator with respect to the
+
operator innum
.
- Definition Classes
- IterableOnceOps
- final def synchronized[T0](arg0: => T0): T0
Executes the code in
body
with an exclusive lock onthis
.Executes the code in
body
with an exclusive lock onthis
.- returns
the result of
body
- Definition Classes
- AnyRef
- def take(n: Int): Iterator[A]
Selects the first
n
elements.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
- Iterator → IterableOnceOps
- def takeWhile(p: (A) => Boolean): Iterator[A]
Selects the longest prefix of elements that satisfy a predicate.
Selects the longest prefix of elements that satisfy a predicate.
The matching prefix starts with the first element of this iterator, and the element following the prefix is the first element that does not satisfy the predicate. The matching prefix may empty, so that this method returns an empty iterator.
Example:
scala> List(1, 2, 3, 100, 4).takeWhile(n => n < 10) val res0: List[Int] = List(1, 2, 3) scala> List(1, 2, 3, 100, 4).takeWhile(n => n == 0) val res1: List[Int] = List()
Use span to obtain both the prefix and suffix. Use filter to retain only those elements from the entire iterator that satisfy the 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
- def tapEach[U](f: (A) => U): Iterator[A]
Applies a side-effecting function to each element in this collection.
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 applyf
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
, converts this iterator to the appropriate representation for the current element typeA
.Given a collection factory
factory
, converts this iterator to the appropriate representation for the current element typeA
. 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]
Converts this iterator to an
Array
.Converts this iterator to an
Array
.Implementation note: DO NOT call Array.from from this method.
- B
The type of elements of the result, a supertype of
A
.- returns
This iterator as an
Array[B]
.
- Definition Classes
- IterableOnceOps
- final def toBuffer[B >: A]: Buffer[B]
Converts this iterator to a
Buffer
.Converts this iterator to a
Buffer
.- B
The type of elements of the result, a supertype of
A
.- returns
This iterator as a
Buffer[B]
.
- Definition Classes
- IterableOnceOps
- Annotations
- @inline()
- def toIndexedSeq: immutable.IndexedSeq[A]
Converts this iterator to an
IndexedSeq
.Converts this iterator to an
IndexedSeq
.- returns
This iterator as an
IndexedSeq[A]
.
- Definition Classes
- IterableOnceOps
- def toList: immutable.List[A]
Converts this iterator to a
List
.Converts this iterator to a
List
.- returns
This iterator as a
List[A]
.
- Definition Classes
- IterableOnceOps
- def toMap[K, V](implicit ev: <:<[A, (K, V)]): immutable.Map[K, V]
Converts this iterator to a
Map
, given an implicit coercion from the iterator's type to a key-value tuple.Converts this iterator to a
Map
, given an implicit coercion from the iterator's type to a key-value tuple.- K
The key type for the resulting map.
- V
The value type for the resulting map.
- ev
An implicit coercion from
A
to[K, V]
.- returns
This iterator as a
Map[K, V]
.
- Definition Classes
- IterableOnceOps
- def toSeq: immutable.Seq[A]
- returns
This iterator as a
Seq[A]
. This is equivalent toto(Seq)
but might be faster.
- Definition Classes
- IterableOnceOps
- def toSet[B >: A]: immutable.Set[B]
Converts this iterator to a
Set
.Converts this iterator to a
Set
.- B
The type of elements of the result, a supertype of
A
.- returns
This iterator as a
Set[B]
.
- Definition Classes
- IterableOnceOps
- def toString(): String
Converts this iterator to a string.
- def toVector: immutable.Vector[A]
Converts this iterator to a
Vector
.Converts this iterator to a
Vector
.- returns
This iterator as a
Vector[A]
.
- Definition Classes
- IterableOnceOps
- final def wait(): Unit
See https://docs.oracle.com/javase/8/docs/api/java/lang/Object.html#wait--.
- Definition Classes
- AnyRef
- Annotations
- @throws(classOf[java.lang.InterruptedException])
- Note
not specified by SLS as a member of AnyRef
- final def wait(arg0: Long, arg1: Int): Unit
See https://docs.oracle.com/javase/8/docs/api/java/lang/Object.html#wait-long-int-
- Definition Classes
- AnyRef
- Annotations
- @throws(classOf[java.lang.InterruptedException])
- Note
not specified by SLS as a member of AnyRef
- final def wait(arg0: Long): Unit
See https://docs.oracle.com/javase/8/docs/api/java/lang/Object.html#wait-long-.
- def withFilter(p: (A) => Boolean): Iterator[A]
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: 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.
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
List("a", "b", "c").zipWithIndex == List(("a", 0), ("b", 1), ("c", 2))
Example:
Deprecated Value Members
- def /:[B](z: B)(op: (B, A) => B): B
- Implicit
- This member is added by an implicit conversion from BufferedIterator[A] toIterableOnceExtensionMethods[A] performed by method iterableOnceExtensionMethods in scala.collection.IterableOnce.
- 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:(bufferedIterator: IterableOnceExtensionMethods[A])./:(z)(op)
- Definition Classes
- IterableOnceExtensionMethods
- Annotations
- @deprecated @inline()
- Deprecated
(Since version 2.13.0) Use .iterator.foldLeft instead
- final def /:[B](z: B)(op: (B, A) => B): B
- Definition Classes
- IterableOnceOps
- Annotations
- @deprecated @inline()
- Deprecated
(Since version 2.13.0) Use foldLeft instead of /:
- def :\[B](z: B)(op: (A, B) => B): B
- Implicit
- This member is added by an implicit conversion from BufferedIterator[A] toIterableOnceExtensionMethods[A] performed by method iterableOnceExtensionMethods in scala.collection.IterableOnce.
- 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:(bufferedIterator: IterableOnceExtensionMethods[A]).:\(z)(op)
- Definition Classes
- IterableOnceExtensionMethods
- Annotations
- @deprecated @inline()
- Deprecated
(Since version 2.13.0) Use .iterator.foldRight instead
- final def :\[B](z: B)(op: (A, B) => B): B
- Definition Classes
- IterableOnceOps
- Annotations
- @deprecated @inline()
- Deprecated
(Since version 2.13.0) Use foldRight instead of :\
- def aggregate[B](z: => B)(seqop: (B, A) => B, combop: (B, B) => B): B
Aggregates the results of applying an operator to subsequent elements.
Aggregates the results of applying an operator to subsequent elements.
Since this method degenerates to
foldLeft
for sequential (non-parallel) collections, where the combining operation is ignored, it is advisable to preferfoldLeft
for that case.For parallel collections, use the
aggregate
method specified byscala.collection.parallel.ParIterableLike
.- B
the result type, produced by
seqop
,combop
, and by this function as a final result.- z
the start value, a neutral element for
seqop
.- seqop
the binary operator used to accumulate the result.
- combop
an associative operator for combining sequential results, unused for sequential collections.
- Definition Classes
- IterableOnceOps
- Annotations
- @deprecated
- Deprecated
(Since version 2.13.0) For sequential collections, prefer
foldLeft(z)(seqop)
. For parallel collections, useParIterableLike#aggregate
.
- def collectFirst[B](f: PartialFunction[A, B]): Option[B]
- Implicit
- This member is added by an implicit conversion from BufferedIterator[A] toIterableOnceExtensionMethods[A] performed by method iterableOnceExtensionMethods in scala.collection.IterableOnce.
- 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:(bufferedIterator: IterableOnceExtensionMethods[A]).collectFirst(f)
- Definition Classes
- IterableOnceExtensionMethods
- Annotations
- @deprecated
- Deprecated
(Since version 2.13.0) Use .iterator.collectFirst(...) instead
- def copyToBuffer(dest: Buffer[A]): Unit
- Implicit
- This member is added by an implicit conversion from BufferedIterator[A] toIterableOnceExtensionMethods[A] performed by method iterableOnceExtensionMethods in scala.collection.IterableOnce.
- Shadowing
- This implicitly inherited member is shadowed by one or more members in this class.
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- Definition Classes
- IterableOnceExtensionMethods
- Annotations
- @deprecated
- Deprecated
(Since version 2.13.0) Use .iterator.copyToBuffer(...) instead
- final def copyToBuffer[B >: A](dest: Buffer[B]): Unit
- Definition Classes
- IterableOnceOps
- Annotations
- @deprecated @inline()
- Deprecated
(Since version 2.13.0) Use
dest ++= coll
instead
- def count(f: (A) => Boolean): Int
- Implicit
- This member is added by an implicit conversion from BufferedIterator[A] toIterableOnceExtensionMethods[A] performed by method iterableOnceExtensionMethods in scala.collection.IterableOnce.
- Shadowing
- This implicitly inherited member is shadowed by one or more members in this class.
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- Definition Classes
- IterableOnceExtensionMethods
- Annotations
- @deprecated
- Deprecated
(Since version 2.13.0) Use .iterator.count(...) instead
- def exists(f: (A) => Boolean): Boolean
- Implicit
- This member is added by an implicit conversion from BufferedIterator[A] toIterableOnceExtensionMethods[A] performed by method iterableOnceExtensionMethods in scala.collection.IterableOnce.
- 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:(bufferedIterator: IterableOnceExtensionMethods[A]).exists(f)
- Definition Classes
- IterableOnceExtensionMethods
- Annotations
- @deprecated
- Deprecated
(Since version 2.13.0) Use .iterator.exists(...) instead
- def filter(f: (A) => Boolean): Iterator[A]
- Implicit
- This member is added by an implicit conversion from BufferedIterator[A] toIterableOnceExtensionMethods[A] performed by method iterableOnceExtensionMethods in scala.collection.IterableOnce.
- Shadowing
- This implicitly inherited member is shadowed by one or more members in this class.
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- Definition Classes
- IterableOnceExtensionMethods
- Annotations
- @deprecated
- Deprecated
(Since version 2.13.0) Use .iterator.filter(...) instead
- def find(p: (A) => Boolean): Option[A]
- Implicit
- This member is added by an implicit conversion from BufferedIterator[A] toIterableOnceExtensionMethods[A] performed by method iterableOnceExtensionMethods in scala.collection.IterableOnce.
- Shadowing
- This implicitly inherited member is shadowed by one or more members in this class.
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- Definition Classes
- IterableOnceExtensionMethods
- Annotations
- @deprecated
- Deprecated
(Since version 2.13.0) Use .iterator.find instead
- def flatMap[B](f: (A) => IterableOnce[B]): IterableOnce[B]
- Implicit
- This member is added by an implicit conversion from BufferedIterator[A] toIterableOnceExtensionMethods[A] performed by method iterableOnceExtensionMethods in scala.collection.IterableOnce.
- 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:(bufferedIterator: IterableOnceExtensionMethods[A]).flatMap(f)
- Definition Classes
- IterableOnceExtensionMethods
- Annotations
- @deprecated
- Deprecated
(Since version 2.13.0) Use .iterator.flatMap instead or consider requiring an Iterable
- def fold[A1 >: A](z: A1)(op: (A1, A1) => A1): A1
- Implicit
- This member is added by an implicit conversion from BufferedIterator[A] toIterableOnceExtensionMethods[A] performed by method iterableOnceExtensionMethods in scala.collection.IterableOnce.
- Shadowing
- This implicitly inherited member is shadowed by one or more members in this class.
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- Definition Classes
- IterableOnceExtensionMethods
- Annotations
- @deprecated
- Deprecated
(Since version 2.13.0) Use .iterator.fold instead
- def foldLeft[B](z: B)(op: (B, A) => B): B
- Implicit
- This member is added by an implicit conversion from BufferedIterator[A] toIterableOnceExtensionMethods[A] performed by method iterableOnceExtensionMethods in scala.collection.IterableOnce.
- Shadowing
- This implicitly inherited member is shadowed by one or more members in this class.
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- Definition Classes
- IterableOnceExtensionMethods
- Annotations
- @deprecated @inline()
- Deprecated
(Since version 2.13.0) Use .iterator.foldLeft instead
- def foldRight[B](z: B)(op: (A, B) => B): B
- Implicit
- This member is added by an implicit conversion from BufferedIterator[A] toIterableOnceExtensionMethods[A] performed by method iterableOnceExtensionMethods in scala.collection.IterableOnce.
- Shadowing
- This implicitly inherited member is shadowed by one or more members in this class.
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- Definition Classes
- IterableOnceExtensionMethods
- Annotations
- @deprecated @inline()
- Deprecated
(Since version 2.13.0) Use .iterator.foldRight instead
- def forall(f: (A) => Boolean): Boolean
- Implicit
- This member is added by an implicit conversion from BufferedIterator[A] toIterableOnceExtensionMethods[A] performed by method iterableOnceExtensionMethods in scala.collection.IterableOnce.
- Shadowing
- This implicitly inherited member is shadowed by one or more members in this class.
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- Definition Classes
- IterableOnceExtensionMethods
- Annotations
- @deprecated
- Deprecated
(Since version 2.13.0) Use .iterator.forall(...) instead
- def foreach[U](f: (A) => U): Unit
- Implicit
- This member is added by an implicit conversion from BufferedIterator[A] toIterableOnceExtensionMethods[A] performed by method iterableOnceExtensionMethods in scala.collection.IterableOnce.
- Shadowing
- This implicitly inherited member is shadowed by one or more members in this class.
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- Definition Classes
- IterableOnceExtensionMethods
- Annotations
- @deprecated @inline()
- Deprecated
(Since version 2.13.0) Use .iterator.foreach(...) instead
- def formatted(fmtstr: String): String
Returns string formatted according to given
format
string.Returns string formatted according to given
format
string. Format strings are as forString.format
(@see java.lang.String.format).- Implicit
- This member is added by an implicit conversion from BufferedIterator[A] toStringFormat[BufferedIterator[A]] performed by method StringFormat in scala.Predef.
- Definition Classes
- StringFormat
- Annotations
- @deprecated @inline()
- Deprecated
(Since version 2.12.16) Use
formatString.format(value)
instead ofvalue.formatted(formatString)
, or use thef""
string interpolator. In Java 15 and later,formatted
resolves to the new method in String which has reversed parameters.
- final def hasDefiniteSize: Boolean
Tests whether this iterator is known to have a finite size.
Tests whether this iterator is known to have a finite size. All strict collections are known to have finite size. For a non-strict collection such as
Stream
, the predicate returnstrue
if all elements have been computed. It returnsfalse
if the stream is not yet evaluated to the end. Non-empty Iterators usually returnfalse
even if they were created from a collection with a known finite size.Note: many collection methods will not work on collections of infinite sizes. The typical failure mode is an infinite loop. These methods always attempt a traversal without checking first that
hasDefiniteSize
returnstrue
. However, checkinghasDefiniteSize
can provide an assurance that size is well-defined and non-termination is not a concern.- returns
true
if this collection is known to have finite size,false
otherwise.
- Definition Classes
- Iterator → IterableOnceOps
- Annotations
- @deprecated @inline()
- Deprecated
(Since version 2.13.0) hasDefiniteSize on Iterator is the same as isEmpty
- See also
method
knownSize
for a more useful alternative
- def isEmpty: Boolean
- Implicit
- This member is added by an implicit conversion from BufferedIterator[A] toIterableOnceExtensionMethods[A] performed by method iterableOnceExtensionMethods in scala.collection.IterableOnce.
- Shadowing
- This implicitly inherited member is shadowed by one or more members in this class.
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- Definition Classes
- IterableOnceExtensionMethods
- Annotations
- @deprecated
- Deprecated
(Since version 2.13.0) Use .iterator.isEmpty instead
- def map[B](f: (A) => B): IterableOnce[B]
- Implicit
- This member is added by an implicit conversion from BufferedIterator[A] toIterableOnceExtensionMethods[A] performed by method iterableOnceExtensionMethods in scala.collection.IterableOnce.
- Shadowing
- This implicitly inherited member is shadowed by one or more members in this class.
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- Definition Classes
- IterableOnceExtensionMethods
- Annotations
- @deprecated
- Deprecated
(Since version 2.13.0) Use .iterator.map instead or consider requiring an Iterable
- def max(implicit ord: math.Ordering[A]): A
- Implicit
- This member is added by an implicit conversion from BufferedIterator[A] toIterableOnceExtensionMethods[A] performed by method iterableOnceExtensionMethods in scala.collection.IterableOnce.
- 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:(bufferedIterator: IterableOnceExtensionMethods[A]).max(ord)
- Definition Classes
- IterableOnceExtensionMethods
- Annotations
- @deprecated
- Deprecated
(Since version 2.13.0) Use .iterator.max instead
- def maxBy[B](f: (A) => B)(implicit cmp: math.Ordering[B]): A
- Implicit
- This member is added by an implicit conversion from BufferedIterator[A] toIterableOnceExtensionMethods[A] performed by method iterableOnceExtensionMethods in scala.collection.IterableOnce.
- Shadowing
- This implicitly inherited member is shadowed by one or more members in this class.
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- Definition Classes
- IterableOnceExtensionMethods
- Annotations
- @deprecated
- Deprecated
(Since version 2.13.0) Use .iterator.maxBy(...) instead
- def min(implicit ord: math.Ordering[A]): A
- Implicit
- This member is added by an implicit conversion from BufferedIterator[A] toIterableOnceExtensionMethods[A] performed by method iterableOnceExtensionMethods in scala.collection.IterableOnce.
- Shadowing
- This implicitly inherited member is shadowed by one or more members in this class.
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- Definition Classes
- IterableOnceExtensionMethods
- Annotations
- @deprecated
- Deprecated
(Since version 2.13.0) Use .iterator.min instead
- def minBy[B](f: (A) => B)(implicit cmp: math.Ordering[B]): A
- Implicit
- This member is added by an implicit conversion from BufferedIterator[A] toIterableOnceExtensionMethods[A] performed by method iterableOnceExtensionMethods in scala.collection.IterableOnce.
- Shadowing
- This implicitly inherited member is shadowed by one or more members in this class.
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- Definition Classes
- IterableOnceExtensionMethods
- Annotations
- @deprecated
- Deprecated
(Since version 2.13.0) Use .iterator.minBy(...) instead
- def mkString: String
- Implicit
- This member is added by an implicit conversion from BufferedIterator[A] toIterableOnceExtensionMethods[A] performed by method iterableOnceExtensionMethods in scala.collection.IterableOnce.
- Shadowing
- This implicitly inherited member is shadowed by one or more members in this class.
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- Definition Classes
- IterableOnceExtensionMethods
- Annotations
- @deprecated
- Deprecated
(Since version 2.13.0) Use .iterator.mkString instead
- def mkString(sep: String): String
- Implicit
- This member is added by an implicit conversion from BufferedIterator[A] toIterableOnceExtensionMethods[A] performed by method iterableOnceExtensionMethods in scala.collection.IterableOnce.
- Shadowing
- This implicitly inherited member is shadowed by one or more members in this class.
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- Definition Classes
- IterableOnceExtensionMethods
- Annotations
- @deprecated
- Deprecated
(Since version 2.13.0) Use .iterator.mkString instead
- def mkString(start: String, sep: String, end: String): String
- Implicit
- This member is added by an implicit conversion from BufferedIterator[A] toIterableOnceExtensionMethods[A] performed by method iterableOnceExtensionMethods in scala.collection.IterableOnce.
- Shadowing
- This implicitly inherited member is shadowed by one or more members in this class.
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- Definition Classes
- IterableOnceExtensionMethods
- Annotations
- @deprecated
- Deprecated
(Since version 2.13.0) Use .iterator.mkString instead
- def nonEmpty: Boolean
- Implicit
- This member is added by an implicit conversion from BufferedIterator[A] toIterableOnceExtensionMethods[A] performed by method iterableOnceExtensionMethods in scala.collection.IterableOnce.
- Shadowing
- This implicitly inherited member is shadowed by one or more members in this class.
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- Definition Classes
- IterableOnceExtensionMethods
- Annotations
- @deprecated
- Deprecated
(Since version 2.13.0) Use .iterator.nonEmpty instead
- def product(implicit num: math.Numeric[A]): A
- Implicit
- This member is added by an implicit conversion from BufferedIterator[A] toIterableOnceExtensionMethods[A] performed by method iterableOnceExtensionMethods in scala.collection.IterableOnce.
- Shadowing
- This implicitly inherited member is shadowed by one or more members in this class.
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- Definition Classes
- IterableOnceExtensionMethods
- Annotations
- @deprecated
- Deprecated
(Since version 2.13.0) Use .iterator.product instead
- def reduce(f: (A, A) => A): A
- Implicit
- This member is added by an implicit conversion from BufferedIterator[A] toIterableOnceExtensionMethods[A] performed by method iterableOnceExtensionMethods in scala.collection.IterableOnce.
- Shadowing
- This implicitly inherited member is shadowed by one or more members in this class.
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- Definition Classes
- IterableOnceExtensionMethods
- Annotations
- @deprecated
- Deprecated
(Since version 2.13.0) Use .iterator.reduce(...) instead
- def reduceLeft(f: (A, A) => A): A
- Implicit
- This member is added by an implicit conversion from BufferedIterator[A] toIterableOnceExtensionMethods[A] performed by method iterableOnceExtensionMethods in scala.collection.IterableOnce.
- Shadowing
- This implicitly inherited member is shadowed by one or more members in this class.
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- Definition Classes
- IterableOnceExtensionMethods
- Annotations
- @deprecated
- Deprecated
(Since version 2.13.0) Use .iterator.reduceLeft(...) instead
- def reduceLeftOption(f: (A, A) => A): Option[A]
- Implicit
- This member is added by an implicit conversion from BufferedIterator[A] toIterableOnceExtensionMethods[A] performed by method iterableOnceExtensionMethods in scala.collection.IterableOnce.
- 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:(bufferedIterator: IterableOnceExtensionMethods[A]).reduceLeftOption(f)
- Definition Classes
- IterableOnceExtensionMethods
- Annotations
- @deprecated
- Deprecated
(Since version 2.13.0) Use .iterator.reduceLeftOption(...) instead
- def reduceOption(f: (A, A) => A): Option[A]
- Implicit
- This member is added by an implicit conversion from BufferedIterator[A] toIterableOnceExtensionMethods[A] performed by method iterableOnceExtensionMethods in scala.collection.IterableOnce.
- 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:(bufferedIterator: IterableOnceExtensionMethods[A]).reduceOption(f)
- Definition Classes
- IterableOnceExtensionMethods
- Annotations
- @deprecated
- Deprecated
(Since version 2.13.0) Use .iterator.reduceOption(...) instead
- def reduceRight(f: (A, A) => A): A
- Implicit
- This member is added by an implicit conversion from BufferedIterator[A] toIterableOnceExtensionMethods[A] performed by method iterableOnceExtensionMethods in scala.collection.IterableOnce.
- 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:(bufferedIterator: IterableOnceExtensionMethods[A]).reduceRight(f)
- Definition Classes
- IterableOnceExtensionMethods
- Annotations
- @deprecated
- Deprecated
(Since version 2.13.0) Use .iterator.reduceRight(...) instead
- def reduceRightOption(f: (A, A) => A): Option[A]
- Implicit
- This member is added by an implicit conversion from BufferedIterator[A] toIterableOnceExtensionMethods[A] performed by method iterableOnceExtensionMethods in scala.collection.IterableOnce.
- 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:(bufferedIterator: IterableOnceExtensionMethods[A]).reduceRightOption(f)
- Definition Classes
- IterableOnceExtensionMethods
- Annotations
- @deprecated
- Deprecated
(Since version 2.13.0) Use .iterator.reduceRightOption(...) instead
- def sameElements[B >: A](that: IterableOnce[B]): Boolean
- Implicit
- This member is added by an implicit conversion from BufferedIterator[A] toIterableOnceExtensionMethods[A] performed by method iterableOnceExtensionMethods in scala.collection.IterableOnce.
- 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:(bufferedIterator: IterableOnceExtensionMethods[A]).sameElements(that)
- Definition Classes
- IterableOnceExtensionMethods
- Annotations
- @deprecated
- Deprecated
(Since version 2.13.0) Use .iterator.sameElements instead
- def scanRight[B](z: B)(op: (A, B) => B): Iterator[B]
- Definition Classes
- Iterator
- Annotations
- @deprecated
- Deprecated
(Since version 2.13.0) Call scanRight on an Iterable instead.
- def seq: BufferedIterator.this.type
- Definition Classes
- Iterator
- Annotations
- @deprecated
- Deprecated
(Since version 2.13.0) Iterator.seq always returns the iterator itself
- def size: Int
- Implicit
- This member is added by an implicit conversion from BufferedIterator[A] toIterableOnceExtensionMethods[A] performed by method iterableOnceExtensionMethods in scala.collection.IterableOnce.
- 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:(bufferedIterator: IterableOnceExtensionMethods[A]).size
- Definition Classes
- IterableOnceExtensionMethods
- Annotations
- @deprecated
- Deprecated
(Since version 2.13.0) Use .iterator.size instead
- def sum(implicit num: math.Numeric[A]): A
- Implicit
- This member is added by an implicit conversion from BufferedIterator[A] toIterableOnceExtensionMethods[A] performed by method iterableOnceExtensionMethods in scala.collection.IterableOnce.
- 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:(bufferedIterator: IterableOnceExtensionMethods[A]).sum(num)
- Definition Classes
- IterableOnceExtensionMethods
- Annotations
- @deprecated
- Deprecated
(Since version 2.13.0) Use .iterator.sum instead
- def to[C1](factory: Factory[A, C1]): C1
- Implicit
- This member is added by an implicit conversion from BufferedIterator[A] toIterableOnceExtensionMethods[A] performed by method iterableOnceExtensionMethods in scala.collection.IterableOnce.
- 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:(bufferedIterator: IterableOnceExtensionMethods[A]).to(factory)
- Definition Classes
- IterableOnceExtensionMethods
- Annotations
- @deprecated
- Deprecated
(Since version 2.13.0) Use .iterator.to(factory) instead
- def toArray[B >: A](implicit arg0: ClassTag[B]): Array[B]
- Implicit
- This member is added by an implicit conversion from BufferedIterator[A] toIterableOnceExtensionMethods[A] performed by method iterableOnceExtensionMethods in scala.collection.IterableOnce.
- 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:(bufferedIterator: IterableOnceExtensionMethods[A]).toArray(arg0)
- Definition Classes
- IterableOnceExtensionMethods
- Annotations
- @deprecated
- Deprecated
(Since version 2.13.0) Use .iterator.toArray
- def toBuffer[B >: A]: Buffer[B]
- Implicit
- This member is added by an implicit conversion from BufferedIterator[A] toIterableOnceExtensionMethods[A] performed by method iterableOnceExtensionMethods in scala.collection.IterableOnce.
- 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:(bufferedIterator: IterableOnceExtensionMethods[A]).toBuffer
- Definition Classes
- IterableOnceExtensionMethods
- Annotations
- @deprecated
- Deprecated
(Since version 2.13.0) Use .iterator.to(ArrayBuffer) instead
- def toIndexedSeq: IndexedSeq[A]
- Implicit
- This member is added by an implicit conversion from BufferedIterator[A] toIterableOnceExtensionMethods[A] performed by method iterableOnceExtensionMethods in scala.collection.IterableOnce.
- 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:(bufferedIterator: IterableOnceExtensionMethods[A]).toIndexedSeq
- Definition Classes
- IterableOnceExtensionMethods
- Annotations
- @deprecated
- Deprecated
(Since version 2.13.0) Use .iterator.toIndexedSeq instead
- final def toIterable: Iterable[A]
- Implicit
- This member is added by an implicit conversion from BufferedIterator[A] toIterableOnceExtensionMethods[A] performed by method iterableOnceExtensionMethods in scala.collection.IterableOnce.
- Definition Classes
- IterableOnceExtensionMethods
- Annotations
- @deprecated @inline()
- Deprecated
(Since version 2.13.0) Use .iterator.to(Iterable) instead
- def toIterator: Iterator[A]
- Implicit
- This member is added by an implicit conversion from BufferedIterator[A] toIterableOnceExtensionMethods[A] performed by method iterableOnceExtensionMethods in scala.collection.IterableOnce.
- 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:(bufferedIterator: IterableOnceExtensionMethods[A]).toIterator
- Definition Classes
- IterableOnceExtensionMethods
- Annotations
- @deprecated @inline()
- Deprecated
(Since version 2.13.0) Use .iterator instead
- final def toIterator: Iterator[A]
- Definition Classes
- IterableOnceOps
- Annotations
- @deprecated @inline()
- Deprecated
(Since version 2.13.0) Use .iterator instead of .toIterator
- def toList: immutable.List[A]
- Implicit
- This member is added by an implicit conversion from BufferedIterator[A] toIterableOnceExtensionMethods[A] performed by method iterableOnceExtensionMethods in scala.collection.IterableOnce.
- 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:(bufferedIterator: IterableOnceExtensionMethods[A]).toList
- Definition Classes
- IterableOnceExtensionMethods
- Annotations
- @deprecated
- Deprecated
(Since version 2.13.0) Use .iterator.to(List) instead
- def toMap[K, V](implicit ev: <:<[A, (K, V)]): immutable.Map[K, V]
- Implicit
- This member is added by an implicit conversion from BufferedIterator[A] toIterableOnceExtensionMethods[A] performed by method iterableOnceExtensionMethods in scala.collection.IterableOnce.
- 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:(bufferedIterator: IterableOnceExtensionMethods[A]).toMap(ev)
- Definition Classes
- IterableOnceExtensionMethods
- Annotations
- @deprecated
- Deprecated
(Since version 2.13.0) Use .iterator.to(Map) instead
- def toSeq: immutable.Seq[A]
- Implicit
- This member is added by an implicit conversion from BufferedIterator[A] toIterableOnceExtensionMethods[A] performed by method iterableOnceExtensionMethods in scala.collection.IterableOnce.
- 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:(bufferedIterator: IterableOnceExtensionMethods[A]).toSeq
- Definition Classes
- IterableOnceExtensionMethods
- Annotations
- @deprecated @inline()
- Deprecated
(Since version 2.13.0) Use .iterator.to(Seq) instead
- def toSet[B >: A]: immutable.Set[B]
- Implicit
- This member is added by an implicit conversion from BufferedIterator[A] toIterableOnceExtensionMethods[A] performed by method iterableOnceExtensionMethods in scala.collection.IterableOnce.
- 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:(bufferedIterator: IterableOnceExtensionMethods[A]).toSet
- Definition Classes
- IterableOnceExtensionMethods
- Annotations
- @deprecated @inline()
- Deprecated
(Since version 2.13.0) Use .iterator.to(Set) instead
- def toStream: immutable.Stream[A]
- Implicit
- This member is added by an implicit conversion from BufferedIterator[A] toIterableOnceExtensionMethods[A] performed by method iterableOnceExtensionMethods in scala.collection.IterableOnce.
- 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:(bufferedIterator: IterableOnceExtensionMethods[A]).toStream
- Definition Classes
- IterableOnceExtensionMethods
- Annotations
- @deprecated @inline()
- Deprecated
(Since version 2.13.0) Use .iterator.to(LazyList) instead
- final def toStream: immutable.Stream[A]
- Definition Classes
- IterableOnceOps
- Annotations
- @deprecated @inline()
- Deprecated
(Since version 2.13.0) Use .to(LazyList) instead of .toStream
- final def toTraversable: Traversable[A]
- Implicit
- This member is added by an implicit conversion from BufferedIterator[A] toIterableOnceExtensionMethods[A] performed by method iterableOnceExtensionMethods in scala.collection.IterableOnce.
- Definition Classes
- IterableOnceExtensionMethods
- Annotations
- @deprecated @inline()
- Deprecated
(Since version 2.13.0) Use .iterator.to(Iterable) instead
- def toVector: immutable.Vector[A]
- Implicit
- This member is added by an implicit conversion from BufferedIterator[A] toIterableOnceExtensionMethods[A] performed by method iterableOnceExtensionMethods in scala.collection.IterableOnce.
- 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:(bufferedIterator: IterableOnceExtensionMethods[A]).toVector
- Definition Classes
- IterableOnceExtensionMethods
- Annotations
- @deprecated @inline()
- Deprecated
(Since version 2.13.0) Use .iterator.to(Vector) instead
- def withFilter(f: (A) => Boolean): Iterator[A]
- Implicit
- This member is added by an implicit conversion from BufferedIterator[A] toIterableOnceExtensionMethods[A] performed by method iterableOnceExtensionMethods in scala.collection.IterableOnce.
- 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:(bufferedIterator: IterableOnceExtensionMethods[A]).withFilter(f)
- Definition Classes
- IterableOnceExtensionMethods
- Annotations
- @deprecated
- Deprecated
(Since version 2.13.0) Use .iterator.withFilter(...) instead
- def →[B](y: B): (BufferedIterator[A], B)
- Implicit
- This member is added by an implicit conversion from BufferedIterator[A] toArrowAssoc[BufferedIterator[A]] performed by method ArrowAssoc in scala.Predef.
- Definition Classes
- ArrowAssoc
- Annotations
- @deprecated
- Deprecated
(Since version 2.13.0) Use
->
instead. If you still wish to display it as one character, consider using a font with programming ligatures such as Fira Code.
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.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.collection.parallel
- Parallel collections (scala-parallel-collections.jar)scala.util.parsing
- Parser combinators (scala-parser-combinators.jar)scala.swing
- A convenient wrapper around Java's GUI framework called Swing (scala-swing.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
.