LinearSeq

trait LinearSeq[+A] extends Seq[A] with GenericTraversableTemplate[A, LinearSeq] with LinearSeqLike[A, LinearSeq[A]]

A base trait for linear sequences.

Linear sequences are defined in terms of three abstract methods, which are assumed to have efficient implementations. These are:

```def isEmpty: Boolean
def head: A
def tail: Repr```

Here, `A` is the type of the sequence elements and `Repr` is the type of the sequence itself.

Linear sequences do not add any new methods to `Seq`, but promise efficient implementations of linear access patterns.

Source
LinearSeq.scala
Linear Supertypes
LinearSeqLike[A, LinearSeq[A]], Seq[A], SeqLike[A, LinearSeq[A]], GenSeq[A], GenSeqLike[A, LinearSeq[A]], Iterable[A], IterableLike[A, LinearSeq[A]], Equals, GenIterable[A], GenIterableLike[A, LinearSeq[A]], Traversable[A], GenTraversable[A], GenericTraversableTemplate[A, LinearSeq], TraversableLike[A, LinearSeq[A]], GenTraversableLike[A, LinearSeq[A]], Parallelizable[A, ParSeq[A]], TraversableOnce[A], GenTraversableOnce[A], FilterMonadic[A, LinearSeq[A]], HasNewBuilder[A, scala.collection.LinearSeq[A] @scala.annotation.unchecked.uncheckedVariance], PartialFunction[Int, A], (Int) ⇒ A, AnyRef, Any
Known Subclasses
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Inherited
1. LinearSeq
2. LinearSeqLike
3. Seq
4. SeqLike
5. GenSeq
6. GenSeqLike
7. Iterable
8. IterableLike
9. Equals
10. GenIterable
11. GenIterableLike
12. Traversable
13. GenTraversable
14. GenericTraversableTemplate
15. TraversableLike
16. GenTraversableLike
17. Parallelizable
18. TraversableOnce
19. GenTraversableOnce
20. FilterMonadic
21. HasNewBuilder
22. PartialFunction
23. Function1
24. AnyRef
25. Any
Implicitly
1. by CollectionsHaveToParArray
2. by MonadOps
3. by any2stringadd
4. by StringFormat
5. by Ensuring
6. by ArrowAssoc
7. by alternateImplicit
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Type Members

1. type Self = LinearSeq[A]

The type implementing this traversable

The type implementing this traversable

Attributes
protected[this]
Definition Classes
TraversableLike
2. class WithFilter extends FilterMonadic[A, Repr]

A class supporting filtered operations.

A class supporting filtered operations. Instances of this class are returned by method `withFilter`.

Definition Classes
TraversableLike

Abstract Value Members

1. abstract def apply(idx: Int): A

Selects an element by its index in the sequence.

Selects an element by its index in the sequence.

Example:

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

scala> x(3)
res1: Int = 4```
idx

The index to select.

returns

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

Definition Classes
SeqLikeGenSeqLike
Exceptions thrown
`IndexOutOfBoundsException`

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

2. abstract def length: Int

The length of the sequence.

The length of the sequence.

Note: will not terminate for infinite-sized collections.

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

returns

the number of elements in this sequence.

Definition Classes
SeqLikeGenSeqLike

Concrete Value Members

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

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

Definition Classes
AnyRef → Any
3. def +(other: String): String

Implicit information
This member is added by an implicit conversion from LinearSeq[A] to any2stringadd[LinearSeq[A]] performed by method any2stringadd in scala.Predef.
Definition Classes
any2stringadd
4. def ++[B](that: GenTraversableOnce[B]): Seq[B]

[use case] Returns a new sequence containing the elements from the left hand operand followed by the elements from the right hand operand.

[use case]

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

Example:

```scala> val a = List(1)
a: List[Int] = List(1)

scala> val b = List(2)
b: List[Int] = List(2)

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

scala> val d = List('a')
d: List[Char] = List(a)

scala> val e = c ++ d
e: List[AnyVal] = List(1, 2, a)```
B

the element type of the returned collection.

that

the traversable to append.

returns

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

Definition Classes
TraversableLikeGenTraversableLike
Full Signature

5. def ++:[B >: A, That](that: Traversable[B])(implicit bf: CanBuildFrom[LinearSeq[A], B, That]): That

As with `++`, returns a new collection containing the elements from the left operand followed by the elements from the right operand.

As with `++`, returns a new collection containing the elements from the left operand followed by the elements from the right operand.

It differs from `++` in that the right operand determines the type of the resulting collection rather than the left one. Mnemonic: the COLon is on the side of the new COLlection type.

Example:

```scala> val x = List(1)
x: List[Int] = List(1)

scala> val y = LinkedList(2)
y: scala.collection.mutable.LinkedList[Int] = LinkedList(2)

scala> val z = x ++: y
z: scala.collection.mutable.LinkedList[Int] = LinkedList(1, 2)```

This overload exists because: for the implementation of `++:` we should reuse that of `++` because many collections override it with more efficient versions.

Since `TraversableOnce` has no `++` method, we have to implement that directly, but `Traversable` and down can use the overload.

B

the element type of the returned collection.

That

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

that

the traversable to append.

bf

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

returns

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

Definition Classes
TraversableLike
6. def ++:[B](that: TraversableOnce[B]): Seq[B]

[use case] As with `++`, returns a new collection containing the elements from the left operand followed by the elements from the right operand.

[use case]

As with `++`, returns a new collection containing the elements from the left operand followed by the elements from the right operand.

It differs from `++` in that the right operand determines the type of the resulting collection rather than the left one. Mnemonic: the COLon is on the side of the new COLlection type.

Example:

```scala> val x = List(1)
x: List[Int] = List(1)

scala> val y = LinkedList(2)
y: scala.collection.mutable.LinkedList[Int] = LinkedList(2)

scala> val z = x ++: y
z: scala.collection.mutable.LinkedList[Int] = LinkedList(1, 2)```
B

the element type of the returned collection.

that

the traversable to append.

returns

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

Definition Classes
TraversableLike
Full Signature

7. def +:(elem: A): Seq[A]

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

[use case]

A copy of the sequence with an element prepended.

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

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

Example:

```scala> val x = List(1)
x: List[Int] = List(1)

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

scala> println(x)
List(1)```
elem

the prepended element

returns

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

Definition Classes
SeqLikeGenSeqLike
Full Signature

8. def ->[B](y: B): (LinearSeq[A], B)

Implicit information
This member is added by an implicit conversion from LinearSeq[A] to ArrowAssoc[LinearSeq[A]] performed by method ArrowAssoc in scala.Predef.
Definition Classes
ArrowAssoc
Annotations
()
9. def /:[B](z: B)(op: (B, A) ⇒ B): B

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

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

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

Examples:

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

```scala> val a = List(1,2,3,4)
a: List[Int] = List(1, 2, 3, 4)

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

scala> val c = (5 /: a)((x,y) => x + y)
c: Int = 15```

Note: will not terminate for infinite-sized collections.

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

B

the result type of the binary operator.

z

the start value.

op

the binary operator.

returns

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

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

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

Definition Classes
TraversableOnceGenTraversableOnce
10. def :+(elem: A): Seq[A]

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

[use case]

A copy of this sequence with an element appended.

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

Note: will not terminate for infinite-sized collections.

Example:

```scala> val a = List(1)
a: List[Int] = List(1)

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

scala> println(a)
List(1)```
elem

the appended element

returns

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

Definition Classes
SeqLikeGenSeqLike
Full Signature

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

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

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

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

Note: will not terminate for infinite-sized collections.

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

Examples:

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

```scala> val a = List(1,2,3,4)
a: List[Int] = List(1, 2, 3, 4)

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

scala> val c = (a :\ 5)((x,y) => x + y)
c: Int = 15```
B

the result type of the binary operator.

z

the start value

op

the binary operator

returns

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

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

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

Definition Classes
TraversableOnceGenTraversableOnce
12. final def ==(arg0: Any): Boolean

Definition Classes
AnyRef → Any
13. def addString(b: StringBuilder): StringBuilder

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

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

Example:

```scala> val a = List(1,2,3,4)
a: List[Int] = List(1, 2, 3, 4)

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

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

the string builder to which elements are appended.

returns

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

Definition Classes
TraversableOnce
14. def addString(b: StringBuilder, sep: String): StringBuilder

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

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

Example:

```scala> val a = List(1,2,3,4)
a: List[Int] = List(1, 2, 3, 4)

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

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

the string builder to which elements are appended.

sep

the separator string.

returns

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

Definition Classes
TraversableOnce
15. def addString(b: StringBuilder, start: String, sep: String, end: String): StringBuilder

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

Appends all elements of this traversable or iterator to a string builder using start, end, and separator strings. The written text begins with the string `start` and ends with the string `end`. Inside, the string representations (w.r.t. the method `toString`) of all elements of this traversable or iterator are separated by the string `sep`.

Example:

```scala> val a = List(1,2,3,4)
a: List[Int] = List(1, 2, 3, 4)

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

scala> a.addString(b , "List(" , ", " , ")")
res5: StringBuilder = List(1, 2, 3, 4)```
b

the string builder to which elements are appended.

start

the starting string.

sep

the separator string.

end

the ending string.

returns

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

Definition Classes
TraversableOnce
16. def aggregate[B](z: ⇒ B)(seqop: (B, A) ⇒ B, combop: (B, B) ⇒ B): B

Aggregates the results of applying an operator to subsequent elements.

Aggregates the results of applying an operator to subsequent elements.

This is a more general form of `fold` and `reduce`. It has similar semantics, but does not require the result to be a supertype of the element type. It traverses the elements in different partitions sequentially, using `seqop` to update the result, and then applies `combop` to results from different partitions. The implementation of this operation may operate on an arbitrary number of collection partitions, so `combop` may be invoked an arbitrary number of times.

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

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

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

B

the type of accumulated results

z

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

seqop

an operator used to accumulate results within a partition

combop

an associative operator used to combine results from different partitions

Definition Classes
TraversableOnceGenTraversableOnce
17. def andThen[C](k: (A) ⇒ C): PartialFunction[Int, C]

Composes this partial function with a transformation function that gets applied to results of this partial function.

Composes this partial function with a transformation function that gets applied to results of this partial function.

C

the result type of the transformation function.

k

the transformation function

returns

a partial function with the same domain as this partial function, which maps arguments `x` to `k(this(x))`.

Definition Classes
PartialFunctionFunction1
18. def applyOrElse[A1 <: Int, B1 >: A](x: A1, default: (A1) ⇒ B1): B1

Applies this partial function to the given argument when it is contained in the function domain.

Applies this partial function to the given argument when it is contained in the function domain. Applies fallback function where this partial function is not defined.

Note that expression `pf.applyOrElse(x, default)` is equivalent to

`if(pf isDefinedAt x) pf(x) else default(x)`

except that `applyOrElse` method can be implemented more efficiently. For all partial function literals the compiler generates an `applyOrElse` implementation which avoids double evaluation of pattern matchers and guards. This makes `applyOrElse` the basis for the efficient implementation for many operations and scenarios, such as:

• combining partial functions into `orElse`/`andThen` chains does not lead to excessive `apply`/`isDefinedAt` evaluation
• `lift` and `unlift` do not evaluate source functions twice on each invocation
• `runWith` allows efficient imperative-style combining of partial functions with conditionally applied actions

For non-literal partial function classes with nontrivial `isDefinedAt` method it is recommended to override `applyOrElse` with custom implementation that avoids double `isDefinedAt` evaluation. This may result in better performance and more predictable behavior w.r.t. side effects.

x

the function argument

default

the fallback function

returns

the result of this function or fallback function application.

Definition Classes
PartialFunction
Since

2.10

19. final def asInstanceOf[T0]: T0

Definition Classes
Any
20. def canEqual(that: Any): Boolean

Method called from equality methods, so that user-defined subclasses can refuse to be equal to other collections of the same kind.

Method called from equality methods, so that user-defined subclasses can refuse to be equal to other collections of the same kind.

that

The object with which this iterable collection should be compared

returns

`true`, if this iterable collection can possibly equal `that`, `false` otherwise. The test takes into consideration only the run-time types of objects but ignores their elements.

Definition Classes
IterableLikeEquals
21. def clone(): AnyRef

Attributes
protected[java.lang]
Definition Classes
AnyRef
Annotations
( ... )
22. def collect[B](pf: PartialFunction[A, B]): Seq[B]

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

[use case]

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

B

the element type of the returned collection.

pf

the partial function which filters and maps the sequence.

returns

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

Definition Classes
TraversableLikeGenTraversableLike
Full Signature

23. def collectFirst[B](pf: PartialFunction[A, B]): Option[B]

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

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

Note: may not terminate for infinite-sized collections.

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

pf

the partial function

returns

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

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

24. def combinations(n: Int): Iterator[LinearSeq[A]]

Iterates over combinations.

Iterates over combinations.

returns

An Iterator which traverses the possible n-element combinations of this sequence.

Definition Classes
SeqLike
Example:
1. `"abbbc".combinations(2) = Iterator(ab, ac, bb, bc)`

25. def companion: GenericCompanion[LinearSeq]

The factory companion object that builds instances of class `Seq`.

The factory companion object that builds instances of class `Seq`. (or its `Iterable` superclass where class `Seq` is not a `Seq`.)

Definition Classes
LinearSeqSeqGenSeqIterableGenIterableTraversableGenTraversableGenericTraversableTemplate
26. def compose[A](g: (A) ⇒ Int): (A) ⇒ A

Composes two instances of Function1 in a new Function1, with this function applied last.

Composes two instances of Function1 in a new Function1, with this function applied last.

A

the type to which function `g` can be applied

g

a function A => T1

returns

a new function `f` such that `f(x) == apply(g(x))`

Definition Classes
Function1
Annotations
()
27. def contains[A1 >: A](elem: A1): Boolean

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

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

Note: may not terminate for infinite-sized collections.

elem

the element to test.

returns

`true` if this sequence has an element that is equal (as determined by `==`) to `elem`, `false` otherwise.

Definition Classes
SeqLike
28. def containsSlice[B](that: GenSeq[B]): Boolean

Tests whether this sequence contains a given sequence as a slice.

Tests whether this sequence contains a given sequence as a slice.

Note: may not terminate for infinite-sized collections.

that

the sequence to test

returns

`true` if this sequence contains a slice with the same elements as `that`, otherwise `false`.

Definition Classes
SeqLike
29. def copyToArray(xs: Array[A], start: Int, len: Int): Unit

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

[use case]

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

Note: will not terminate for infinite-sized collections.

xs

the array to fill.

start

the starting index.

len

the maximal number of elements to copy.

Definition Classes
IterableLikeTraversableLikeTraversableOnceGenTraversableOnce
Full Signature

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

[use case] Copies values of this sequence to an array.

[use case]

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

Note: will not terminate for infinite-sized collections.

xs

the array to fill.

Definition Classes
TraversableOnceGenTraversableOnce
Full Signature

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

[use case] Copies values of this sequence to an array.

[use case]

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

Note: will not terminate for infinite-sized collections.

xs

the array to fill.

start

the starting index.

Definition Classes
TraversableOnceGenTraversableOnce
Full Signature

32. def copyToBuffer[B >: A](dest: Buffer[B]): Unit

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

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

Note: will not terminate for infinite-sized collections.

dest

The buffer to which elements are copied.

Definition Classes
TraversableOnce
33. final def corresponds[B](that: GenSeq[B])(p: (A, B) ⇒ Boolean): Boolean

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

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

B

the type of the elements of `that`

that

the other sequence

p

the test predicate, which relates elements from both sequences

returns

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

Definition Classes
LinearSeqLikeSeqLikeGenSeqLike
Annotations
()
34. def count(p: (A) ⇒ Boolean): Int

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

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

p

the predicate used to test elements.

returns

the number of elements satisfying the predicate `p`.

Definition Classes
TraversableOnceGenTraversableOnce
35. def diff(that: Seq[A]): Seq[A]

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

[use case]

Computes the multiset difference between this sequence and another sequence.

Note: will not terminate for infinite-sized collections.

that

the sequence of elements to remove

returns

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

Definition Classes
SeqLikeGenSeqLike
Full Signature

36. def distinct: LinearSeq[A]

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

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

Note: will not terminate for infinite-sized collections.

returns

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

Definition Classes
SeqLikeGenSeqLike
37. def drop(n: Int): LinearSeq[A]

Selects all elements except first n ones.

Selects all elements except first n ones.

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

n

the number of elements to drop from this iterable collection.

returns

a iterable collection consisting of all elements of this iterable collection except the first `n` ones, or else the empty iterable collection, if this iterable collection has less than `n` elements.

Definition Classes
IterableLikeTraversableLikeGenTraversableLike
38. def dropRight(n: Int): LinearSeq[A]

Selects all elements except last n ones.

Selects all elements except last n ones.

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

n

The number of elements to take

returns

a iterable collection consisting of all elements of this iterable collection except the last `n` ones, or else the empty iterable collection, if this iterable collection has less than `n` elements.

Definition Classes
IterableLike
39. def dropWhile(p: (A) ⇒ Boolean): LinearSeq[A]

Drops longest prefix of elements that satisfy a predicate.

Drops longest prefix of elements that satisfy a predicate.

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

returns

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

Definition Classes
TraversableLikeGenTraversableLike
40. def endsWith[B](that: GenSeq[B]): Boolean

Tests whether this sequence ends with the given sequence.

Tests whether this sequence ends with the given sequence.

Note: will not terminate for infinite-sized collections.

that

the sequence to test

returns

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

Definition Classes
SeqLikeGenSeqLike
41. def ensuring(cond: (LinearSeq[A]) ⇒ Boolean, msg: ⇒ Any): LinearSeq[A]

Implicit information
This member is added by an implicit conversion from LinearSeq[A] to Ensuring[LinearSeq[A]] performed by method Ensuring in scala.Predef.
Definition Classes
Ensuring
42. def ensuring(cond: (LinearSeq[A]) ⇒ Boolean): LinearSeq[A]

Implicit information
This member is added by an implicit conversion from LinearSeq[A] to Ensuring[LinearSeq[A]] performed by method Ensuring in scala.Predef.
Definition Classes
Ensuring
43. def ensuring(cond: Boolean, msg: ⇒ Any): LinearSeq[A]

Implicit information
This member is added by an implicit conversion from LinearSeq[A] to Ensuring[LinearSeq[A]] performed by method Ensuring in scala.Predef.
Definition Classes
Ensuring
44. def ensuring(cond: Boolean): LinearSeq[A]

Implicit information
This member is added by an implicit conversion from LinearSeq[A] to Ensuring[LinearSeq[A]] performed by method Ensuring in scala.Predef.
Definition Classes
Ensuring
45. final def eq(arg0: AnyRef): Boolean

Definition Classes
AnyRef
46. def equals(that: Any): Boolean

The equals method for arbitrary sequences.

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

that

The object to compare the sequence to

returns

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

Definition Classes
GenSeqLikeEquals → Any
47. def exists(p: (A) ⇒ Boolean): Boolean

Tests whether a predicate holds for some of the elements of this iterable collection.

Tests whether a predicate holds for some of the elements of this iterable collection.

Note: may not terminate for infinite-sized collections.

p

the predicate used to test elements.

returns

`false` if this iterable collection is empty, otherwise `true` if the given predicate `p` holds for some of the elements of this iterable collection, otherwise `false`

Definition Classes
IterableLikeTraversableLikeTraversableOnceGenTraversableOnce
48. def filter(p: (A) ⇒ Boolean): LinearSeq[A]

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

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

p

the predicate used to test elements.

returns

a new traversable collection consisting of all elements of this traversable collection that satisfy the given predicate `p`. The order of the elements is preserved.

Definition Classes
TraversableLikeGenTraversableLike
49. def filterNot(p: (A) ⇒ Boolean): LinearSeq[A]

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

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

p

the predicate used to test elements.

returns

a new traversable collection consisting of all elements of this traversable collection that do not satisfy the given predicate `p`. The order of the elements is preserved.

Definition Classes
TraversableLikeGenTraversableLike
50. def finalize(): Unit

Attributes
protected[java.lang]
Definition Classes
AnyRef
Annotations
( classOf[java.lang.Throwable] )
51. def find(p: (A) ⇒ Boolean): Option[A]

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

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

Note: may not terminate for infinite-sized collections.

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

p

the predicate used to test elements.

returns

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

Definition Classes
IterableLikeTraversableLikeTraversableOnceGenTraversableOnce
52. def flatMap[B](f: (A) ⇒ GenTraversableOnce[B]): Seq[B]

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

[use case]

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

For example:

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

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

```// lettersOf will return a Seq[Char] of likely repeated letters, instead of a Set
def lettersOf(words: Seq[String]) = words flatMap (word => word.toSet)

// lettersOf will return a Set[Char], not a Seq
def lettersOf(words: Seq[String]) = words.toSet flatMap (word => word.toSeq)

// xs will be an Iterable[Int]
val xs = Map("a" -> List(11,111), "b" -> List(22,222)).flatMap(_._2)

// ys will be a Map[Int, Int]
val ys = Map("a" -> List(1 -> 11,1 -> 111), "b" -> List(2 -> 22,2 -> 222)).flatMap(_._2)```
B

the element type of the returned collection.

f

the function to apply to each element.

returns

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

Definition Classes
TraversableLikeGenTraversableLikeFilterMonadic
Full Signature

53. def flatten[B]: Seq[B]

[use case] Converts this sequence of traversable collections into a sequence formed by the elements of these traversable collections.

[use case]

Converts this sequence of traversable collections into a sequence formed by the elements of these traversable collections.

The resulting collection's type will be guided by the static type of sequence. For example:

```val xs = List(
Set(1, 2, 3),
Set(1, 2, 3)
).flatten
// xs == List(1, 2, 3, 1, 2, 3)

val ys = Set(
List(1, 2, 3),
List(3, 2, 1)
).flatten
// ys == Set(1, 2, 3)```
B

the type of the elements of each traversable collection.

returns

a new sequence resulting from concatenating all element sequences.

Definition Classes
GenericTraversableTemplate
Full Signature

54. def fold[A1 >: A](z: A1)(op: (A1, A1) ⇒ A1): A1

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

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

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

A1

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

z

a neutral element for the fold operation; may be added to the result an arbitrary number of times, and must not change the result (e.g., `Nil` for list concatenation, 0 for addition, or 1 for multiplication.)

op

a binary operator that must be associative

returns

the result of applying fold operator `op` between all the elements and `z`

Definition Classes
TraversableOnceGenTraversableOnce
55. def foldLeft[B](z: B)(op: (B, A) ⇒ B): B

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

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

Note: will not terminate for infinite-sized collections.

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

B

the result type of the binary operator.

z

the start value.

op

the binary operator.

returns

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

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

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

Definition Classes
TraversableOnceGenTraversableOnce
56. def foldRight[B](z: B)(op: (A, B) ⇒ B): B

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

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

Note: will not terminate for infinite-sized collections.

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

B

the result type of the binary operator.

z

the start value.

op

the binary operator.

returns

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

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

where `x1, ..., xn` are the elements of this iterable collection.

Definition Classes
IterableLikeTraversableOnceGenTraversableOnce
57. def forall(p: (A) ⇒ Boolean): Boolean

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

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

Note: may not terminate for infinite-sized collections.

p

the predicate used to test elements.

returns

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

Definition Classes
IterableLikeTraversableLikeTraversableOnceGenTraversableOnce
58. def foreach(f: (A) ⇒ Unit): Unit

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

[use case]

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

Note: this method underlies the implementation of most other bulk operations. Subclasses should re-implement this method if a more efficient implementation exists.

f

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

Definition Classes
IterableLikeTraversableLikeGenTraversableLikeTraversableOnceGenTraversableOnceFilterMonadic
Full Signature

59. def formatted(fmtstr: String): String

Returns string formatted according to given `format` string.

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

Implicit information
This member is added by an implicit conversion from LinearSeq[A] to StringFormat[LinearSeq[A]] performed by method StringFormat in scala.Predef.
Definition Classes
StringFormat
Annotations
()
60. def genericBuilder[B]: Builder[B, LinearSeq[B]]

The generic builder that builds instances of CC at arbitrary element types.

The generic builder that builds instances of CC at arbitrary element types.

Definition Classes
GenericTraversableTemplate
61. final def getClass(): Class[_]

Definition Classes
AnyRef → Any
62. def groupBy[K](f: (A) ⇒ K): immutable.Map[K, LinearSeq[A]]

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

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

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

K

the type of keys returned by the discriminator function.

f

the discriminator function.

returns

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

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

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

Definition Classes
TraversableLikeGenTraversableLike
63. def grouped(size: Int): Iterator[LinearSeq[A]]

Partitions elements in fixed size iterable collections.

Partitions elements in fixed size iterable collections.

size

the number of elements per group

returns

An iterator producing iterable collections of size `size`, except the last will be less than size `size` if the elements don't divide evenly.

Definition Classes
IterableLike
See also

scala.collection.Iterator, method `grouped`

64. def hasDefiniteSize: Boolean

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

Tests whether this traversable collection is known to have a finite size. All strict collections are known to have finite size. For a non-strict collection such as `Stream`, the predicate returns `true` if all elements have been computed. It returns `false` if the stream is not yet evaluated to the end.

Note: many collection methods will not work on collections of infinite sizes.

returns

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

Definition Classes
TraversableLikeTraversableOnceGenTraversableOnce
65. def hashCode(): Int

Hashcodes for `Seq` produce a value from the hashcodes of all the elements of the sequence.

Hashcodes for `Seq` produce a value from the hashcodes of all the elements of the sequence.

Definition Classes
LinearSeqLikeGenSeqLike → AnyRef → Any
66. def head: A

Selects the first element of this iterable collection.

Selects the first element of this iterable collection.

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

returns

the first element of this iterable collection.

Definition Classes
IterableLikeTraversableLikeGenTraversableLike
Exceptions thrown
`NoSuchElementException`

if the iterable collection is empty.

67. def headOption: Option[A]

Optionally selects the first element.

Optionally selects the first element.

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

returns

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

Definition Classes
TraversableLikeGenTraversableLike
68. def indexOf(elem: A, from: Int): Int

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

[use case]

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

Note: may not terminate for infinite-sized collections.

elem

the element value to search for.

from

the start index

returns

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

Definition Classes
GenSeqLike
Full Signature

69. def indexOf(elem: A): Int

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

[use case]

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

Note: may not terminate for infinite-sized collections.

elem

the element value to search for.

returns

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

Definition Classes
GenSeqLike
Full Signature

70. def indexOfSlice[B >: A](that: GenSeq[B], from: Int): Int

Finds first index after or at a start index where this sequence contains a given sequence as a slice.

Finds first index after or at a start index where this sequence contains a given sequence as a slice.

Note: may not terminate for infinite-sized collections.

that

the sequence to test

from

the start index

returns

the first index `>= from` such that the elements of this sequence starting at this index match the elements of sequence `that`, or `-1` of no such subsequence exists.

Definition Classes
SeqLike
71. def indexOfSlice[B >: A](that: GenSeq[B]): Int

Finds first index where this sequence contains a given sequence as a slice.

Finds first index where this sequence contains a given sequence as a slice.

Note: may not terminate for infinite-sized collections.

that

the sequence to test

returns

the first index such that the elements of this sequence starting at this index match the elements of sequence `that`, or `-1` of no such subsequence exists.

Definition Classes
SeqLike
72. def indexWhere(p: (A) ⇒ Boolean, from: Int): Int

Finds index of the first element satisfying some predicate after or at some start index.

Finds index of the first element satisfying some predicate after or at some start index.

Note: may not terminate for infinite-sized collections.

p

the predicate used to test elements.

from

the start index

returns

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

Definition Classes
SeqLikeGenSeqLike
73. def indexWhere(p: (A) ⇒ Boolean): Int

Finds index of first element satisfying some predicate.

Finds index of first element satisfying some predicate.

Note: may not terminate for infinite-sized collections.

p

the predicate used to test elements.

returns

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

Definition Classes
GenSeqLike
74. def indices: immutable.Range

Produces the range of all indices of this sequence.

Produces the range of all indices of this sequence.

returns

a `Range` value from `0` to one less than the length of this sequence.

Definition Classes
SeqLike
75. def init: LinearSeq[A]

Selects all elements except the last.

Selects all elements except the last.

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

returns

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

Definition Classes
TraversableLikeGenTraversableLike
Exceptions thrown
`UnsupportedOperationException`

if the traversable collection is empty.

76. def inits: Iterator[LinearSeq[A]]

Iterates over the inits of this traversable collection.

Iterates over the inits of this traversable collection. The first value will be this traversable collection and the final one will be an empty traversable collection, with the intervening values the results of successive applications of `init`.

returns

an iterator over all the inits of this traversable collection

Definition Classes
TraversableLike
Example:
1. `List(1,2,3).inits = Iterator(List(1,2,3), List(1,2), List(1), Nil)`

77. def intersect(that: Seq[A]): Seq[A]

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

[use case]

Computes the multiset intersection between this sequence and another sequence.

Note: may not terminate for infinite-sized collections.

that

the sequence of elements to intersect with.

returns

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

Definition Classes
SeqLikeGenSeqLike
Full Signature

78. def isDefinedAt(idx: Int): Boolean

Tests whether this general sequence contains given index.

Tests whether this general sequence contains given index.

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

idx

the index to test

returns

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

Definition Classes
GenSeqLike
79. def isEmpty: Boolean

Tests whether this sequence is empty.

Tests whether this sequence is empty.

returns

`true` if the sequence contain no elements, `false` otherwise.

Definition Classes
SeqLikeIterableLikeTraversableLikeTraversableOnceGenTraversableOnce
80. final def isInstanceOf[T0]: Boolean

Definition Classes
Any
81. final def isTraversableAgain: Boolean

Tests whether this traversable collection can be repeatedly traversed.

Tests whether this traversable collection can be repeatedly traversed.

returns

`true`

Definition Classes
TraversableLikeGenTraversableLikeGenTraversableOnce
82. def iterator: Iterator[A]

Creates a new iterator over all elements contained in this iterable object.

Creates a new iterator over all elements contained in this iterable object.

returns

the new iterator

Definition Classes
LinearSeqLikeIterableLikeGenIterableLike
83. def last: A

Selects the last element.

Selects the last element.

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

returns

The last element of this traversable collection.

Definition Classes
TraversableLikeGenTraversableLike
Exceptions thrown
NoSuchElementException

If the traversable collection is empty.

84. def lastIndexOf(elem: A, end: Int): Int

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

[use case]

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

elem

the element value to search for.

end

the end index.

returns

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

Definition Classes
GenSeqLike
Full Signature

85. def lastIndexOf(elem: A): Int

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

[use case]

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

Note: will not terminate for infinite-sized collections.

elem

the element value to search for.

returns

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

Definition Classes
GenSeqLike
Full Signature

86. def lastIndexOfSlice[B >: A](that: GenSeq[B], end: Int): Int

Finds last index before or at a given end index where this sequence contains a given sequence as a slice.

Finds last index before or at a given end index where this sequence contains a given sequence as a slice.

that

the sequence to test

end

the end index

returns

the last index `<= end` such that the elements of this sequence starting at this index match the elements of sequence `that`, or `-1` of no such subsequence exists.

Definition Classes
SeqLike
87. def lastIndexOfSlice[B >: A](that: GenSeq[B]): Int

Finds last index where this sequence contains a given sequence as a slice.

Finds last index where this sequence contains a given sequence as a slice.

Note: will not terminate for infinite-sized collections.

that

the sequence to test

returns

the last index such that the elements of this sequence starting a this index match the elements of sequence `that`, or `-1` of no such subsequence exists.

Definition Classes
SeqLike
88. def lastIndexWhere(p: (A) ⇒ Boolean, end: Int): Int

Finds index of last element satisfying some predicate before or at given end index.

Finds index of last element satisfying some predicate before or at given end index.

p

the predicate used to test elements.

returns

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

Definition Classes
SeqLikeGenSeqLike
89. def lastIndexWhere(p: (A) ⇒ Boolean): Int

Finds index of last element satisfying some predicate.

Finds index of last element satisfying some predicate.

Note: will not terminate for infinite-sized collections.

p

the predicate used to test elements.

returns

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

Definition Classes
GenSeqLike
90. def lastOption: Option[A]

Optionally selects the last element.

Optionally selects the last element.

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

returns

the last element of this traversable collection\$ if it is nonempty, `None` if it is empty.

Definition Classes
TraversableLikeGenTraversableLike
91. def lengthCompare(len: Int): Int

Compares the length of this sequence to a test value.

Compares the length of this sequence to a test value.

len

the test value that gets compared with the length.

returns

A value `x` where

```x <  0       if this.length <  len
x == 0       if this.length == len
x >  0       if this.length >  len```

The method as implemented here does not call `length` directly; its running time is `O(length min len)` instead of `O(length)`. The method should be overwritten if computing `length` is cheap.

Definition Classes
SeqLike
92. def lift: (Int) ⇒ Option[A]

Turns this partial function into a plain function returning an `Option` result.

Turns this partial function into a plain function returning an `Option` result.

returns

a function that takes an argument `x` to `Some(this(x))` if `this` is defined for `x`, and to `None` otherwise.

Definition Classes
PartialFunction
See also

Function.unlift

93. def map[B](f: (A) ⇒ B): Seq[B]

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

[use case]

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

B

the element type of the returned collection.

f

the function to apply to each element.

returns

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

Definition Classes
TraversableLikeGenTraversableLikeFilterMonadic
Full Signature

94. def max: A

[use case] Finds the largest element.

[use case]

Finds the largest element.

returns

the largest element of this sequence.

Definition Classes
TraversableOnceGenTraversableOnce
Full Signature

95. def maxBy[B](f: (A) ⇒ B): A

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

[use case]

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

B

The result type of the function f.

f

The measuring function.

returns

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

Definition Classes
TraversableOnceGenTraversableOnce
Full Signature

96. def min: A

[use case] Finds the smallest element.

[use case]

Finds the smallest element.

returns

the smallest element of this sequence

Definition Classes
TraversableOnceGenTraversableOnce
Full Signature

97. def minBy[B](f: (A) ⇒ B): A

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

[use case]

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

B

The result type of the function f.

f

The measuring function.

returns

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

Definition Classes
TraversableOnceGenTraversableOnce
Full Signature

98. def mkString: String

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

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

returns

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

Definition Classes
TraversableOnceGenTraversableOnce
99. def mkString(sep: String): String

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

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

sep

the separator string.

returns

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

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

100. def mkString(start: String, sep: String, end: String): String

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

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

start

the starting string.

sep

the separator string.

end

the ending string.

returns

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

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

101. final def ne(arg0: AnyRef): Boolean

Definition Classes
AnyRef
102. def newBuilder: Builder[A, LinearSeq[A]]

The builder that builds instances of type CC[A]

The builder that builds instances of type CC[A]

Attributes
protected[this]
Definition Classes
GenericTraversableTemplateHasNewBuilder
103. def nonEmpty: Boolean

Tests whether the traversable or iterator is not empty.

Tests whether the traversable or iterator is not empty.

returns

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

Definition Classes
TraversableOnceGenTraversableOnce
104. final def notify(): Unit

Definition Classes
AnyRef
105. final def notifyAll(): Unit

Definition Classes
AnyRef
106. def orElse[A1 <: Int, B1 >: A](that: PartialFunction[A1, B1]): PartialFunction[A1, B1]

Composes this partial function with a fallback partial function which gets applied where this partial function is not defined.

Composes this partial function with a fallback partial function which gets applied where this partial function is not defined.

A1

the argument type of the fallback function

B1

the result type of the fallback function

that

the fallback function

returns

a partial function which has as domain the union of the domains of this partial function and `that`. The resulting partial function takes `x` to `this(x)` where `this` is defined, and to `that(x)` where it is not.

Definition Classes
PartialFunction
107. def padTo(len: Int, elem: A): Seq[A]

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

[use case]

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

len

the target length

elem

the padding value

returns

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

Definition Classes
SeqLikeGenSeqLike
Full Signature

108. def par: ParSeq[A]

Returns a parallel implementation of this collection.

Returns a parallel implementation of this collection.

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

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

All parallel collections return a reference to themselves.

returns

a parallel implementation of this collection

Definition Classes
Parallelizable
109. def parCombiner: Combiner[A, ParSeq[A]]

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

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

returns

a combiner for the parallel collection of type `ParRepr`

Attributes
protected[this]
Definition Classes
SeqLikeTraversableLikeParallelizable
110. def partition(p: (A) ⇒ Boolean): (LinearSeq[A], LinearSeq[A])

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

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

p

the predicate on which to partition.

returns

a pair of traversable collections: the first traversable collection consists of all elements that satisfy the predicate `p` and the second traversable collection consists of all elements that don't. The relative order of the elements in the resulting traversable collections is the same as in the original traversable collection.

Definition Classes
TraversableLikeGenTraversableLike
111. def patch(from: Int, that: GenSeq[A], replaced: Int): Seq[A]

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

[use case]

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

from

the index of the first replaced element

replaced

the number of elements to drop in the original sequence

returns

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

Definition Classes
SeqLikeGenSeqLike
Full Signature

112. def permutations: Iterator[LinearSeq[A]]

Iterates over distinct permutations.

Iterates over distinct permutations.

returns

An Iterator which traverses the distinct permutations of this sequence.

Definition Classes
SeqLike
Example:
1. `"abb".permutations = Iterator(abb, bab, bba)`

113. def prefixLength(p: (A) ⇒ Boolean): Int

Returns the length of the longest prefix whose elements all satisfy some predicate.

Returns the length of the longest prefix whose elements all satisfy some predicate.

Note: may not terminate for infinite-sized collections.

p

the predicate used to test elements.

returns

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

Definition Classes
GenSeqLike
114. def product: A

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

[use case]

Multiplies up the elements of this collection.

returns

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

Definition Classes
TraversableOnceGenTraversableOnce
Full Signature

115. def reduce[A1 >: A](op: (A1, A1) ⇒ A1): A1

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

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

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

A1

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

op

A binary operator that must be associative.

returns

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

Definition Classes
TraversableOnceGenTraversableOnce
Exceptions thrown
UnsupportedOperationException

if this traversable or iterator is empty.

116. def reduceLeft[B >: A](op: (B, A) ⇒ B): B

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

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

Note: will not terminate for infinite-sized collections.

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

B

the result type of the binary operator.

op

the binary operator.

returns

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

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

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

Definition Classes
TraversableOnce
Exceptions thrown
`UnsupportedOperationException`

if this traversable or iterator is empty.

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

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

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

Note: will not terminate for infinite-sized collections.

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

B

the result type of the binary operator.

op

the binary operator.

returns

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

Definition Classes
TraversableOnceGenTraversableOnce
118. def reduceOption[A1 >: A](op: (A1, A1) ⇒ A1): Option[A1]

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

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

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

A1

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

op

A binary operator that must be associative.

returns

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

Definition Classes
TraversableOnceGenTraversableOnce
119. def reduceRight[B >: A](op: (A, B) ⇒ B): B

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

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

Note: will not terminate for infinite-sized collections.

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

B

the result type of the binary operator.

op

the binary operator.

returns

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

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

where `x1, ..., xn` are the elements of this iterable collection.

Definition Classes
IterableLikeTraversableOnceGenTraversableOnce
Exceptions thrown
`UnsupportedOperationException`

if this iterable collection is empty.

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

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

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

Note: will not terminate for infinite-sized collections.

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

B

the result type of the binary operator.

op

the binary operator.

returns

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

Definition Classes
TraversableOnceGenTraversableOnce
121. def repr: LinearSeq[A]

The collection of type traversable collection underlying this `TraversableLike` object.

The collection of type traversable collection underlying this `TraversableLike` object. By default this is implemented as the `TraversableLike` object itself, but this can be overridden.

Definition Classes
TraversableLikeGenTraversableLike
122. def reverse: LinearSeq[A]

Returns new sequence with elements in reversed order.

Returns new sequence with elements in reversed order.

Note: will not terminate for infinite-sized collections.

returns

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

Definition Classes
SeqLikeGenSeqLike
123. def reverseIterator: Iterator[A]

An iterator yielding elements in reversed order.

An iterator yielding elements in reversed order.

Note: will not terminate for infinite-sized collections.

Note: `xs.reverseIterator` is the same as `xs.reverse.iterator` but might be more efficient.

returns

an iterator yielding the elements of this sequence in reversed order

Definition Classes
SeqLike
124. def reverseMap[B](f: (A) ⇒ B): Seq[B]

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

[use case]

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

Note: will not terminate for infinite-sized collections.

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

B

the element type of the returned collection.

f

the function to apply to each element.

returns

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

Definition Classes
SeqLikeGenSeqLike
Full Signature

125. def reversed: List[A]

Attributes
protected[this]
Definition Classes
TraversableOnce
126. def runWith[U](action: (A) ⇒ U): (Int) ⇒ Boolean

Composes this partial function with an action function which gets applied to results of this partial function.

Composes this partial function with an action function which gets applied to results of this partial function. The action function is invoked only for its side effects; its result is ignored.

Note that expression `pf.runWith(action)(x)` is equivalent to

`if(pf isDefinedAt x) { action(pf(x)); true } else false`

except that `runWith` is implemented via `applyOrElse` and thus potentially more efficient. Using `runWith` avoids double evaluation of pattern matchers and guards for partial function literals.

action

the action function

returns

a function which maps arguments `x` to `isDefinedAt(x)`. The resulting function runs `action(this(x))` where `this` is defined.

Definition Classes
PartialFunction
Since

2.10

See also

`applyOrElse`.

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

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

[use case]

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

Note: will not terminate for infinite-sized collections.

that

the collection to compare with.

returns

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

Definition Classes
IterableLikeGenIterableLike
Full Signature

128. def scan[B >: A, That](z: B)(op: (B, B) ⇒ B)(implicit cbf: CanBuildFrom[LinearSeq[A], B, That]): That

Computes a prefix scan of the elements of the collection.

Computes a prefix scan of the elements of the collection.

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

B

element type of the resulting collection

That

type of the resulting collection

z

neutral element for the operator `op`

op

the associative operator for the scan

cbf

combiner factory which provides a combiner

returns

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

Definition Classes
TraversableLikeGenTraversableLike
129. def scanLeft[B, That](z: B)(op: (B, A) ⇒ B)(implicit bf: CanBuildFrom[LinearSeq[A], B, That]): That

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

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

Note: will not terminate for infinite-sized collections.

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

B

the type of the elements in the resulting collection

That

the actual type of the resulting collection

z

the initial value

op

the binary operator applied to the intermediate result and the element

bf

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

returns

collection with intermediate results

Definition Classes
TraversableLikeGenTraversableLike
130. def scanRight[B, That](z: B)(op: (A, B) ⇒ B)(implicit bf: CanBuildFrom[LinearSeq[A], B, That]): That

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

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

Note: will not terminate for infinite-sized collections.

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

Example:

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

the type of the elements in the resulting collection

That

the actual type of the resulting collection

z

the initial value

op

the binary operator applied to the intermediate result and the element

bf

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

returns

collection with intermediate results

Definition Classes
TraversableLikeGenTraversableLike
Annotations
@migration
Migration

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

131. def segmentLength(p: (A) ⇒ Boolean, from: Int): Int

Computes length of longest segment whose elements all satisfy some predicate.

Computes length of longest segment whose elements all satisfy some predicate.

Note: may not terminate for infinite-sized collections.

p

the predicate used to test elements.

from

the index where the search starts.

returns

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

Definition Classes
SeqLikeGenSeqLike
132. def seq: LinearSeq[A]

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

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

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

returns

a sequential view of the collection.

Definition Classes
LinearSeqLinearSeqLikeSeqGenSeqGenSeqLikeIterableGenIterableTraversableGenTraversableParallelizableTraversableOnceGenTraversableOnce
133. def size: Int

The size of this sequence, equivalent to `length`.

The size of this sequence, equivalent to `length`.

Note: will not terminate for infinite-sized collections.

returns

the number of elements in this sequence.

Definition Classes
SeqLikeGenTraversableLikeTraversableOnceGenTraversableOnce
134. def slice(from: Int, until: Int): LinearSeq[A]

Selects an interval of elements.

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

`from <= indexOf(x) < until`

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

returns

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

Definition Classes
IterableLikeTraversableLikeGenTraversableLike
135. def sliding(size: Int, step: Int): Iterator[LinearSeq[A]]

Groups elements in fixed size blocks by passing a "sliding window" over them (as opposed to partitioning them, as is done in grouped.)

Groups elements in fixed size blocks by passing a "sliding window" over them (as opposed to partitioning them, as is done in grouped.)

size

the number of elements per group

step

the distance between the first elements of successive groups (defaults to 1)

returns

An iterator producing iterable collections of size `size`, except the last and the only element will be truncated if there are fewer elements than size.

Definition Classes
IterableLike
See also

scala.collection.Iterator, method `sliding`

136. def sliding(size: Int): Iterator[LinearSeq[A]]

Groups elements in fixed size blocks by passing a "sliding window" over them (as opposed to partitioning them, as is done in grouped.)

Groups elements in fixed size blocks by passing a "sliding window" over them (as opposed to partitioning them, as is done in grouped.)

size

the number of elements per group

returns

An iterator producing iterable collections of size `size`, except the last and the only element will be truncated if there are fewer elements than size.

Definition Classes
IterableLike
See also

scala.collection.Iterator, method `sliding`

137. def sortBy[B](f: (A) ⇒ B)(implicit ord: math.Ordering[B]): LinearSeq[A]

Sorts this `Seq` according to the Ordering which results from transforming an implicitly given Ordering with a transformation function.

Sorts this `Seq` according to the Ordering which results from transforming an implicitly given Ordering with a transformation function.

B

the target type of the transformation `f`, and the type where the ordering `ord` is defined.

f

the transformation function mapping elements to some other domain `B`.

ord

the ordering assumed on domain `B`.

returns

a sequence consisting of the elements of this sequence sorted according to the ordering where `x < y` if `ord.lt(f(x), f(y))`.

Definition Classes
SeqLike
Example:
1. ```val words = "The quick brown fox jumped over the lazy dog".split(' ')
// this works because scala.Ordering will implicitly provide an Ordering[Tuple2[Int, Char]]
words.sortBy(x => (x.length, x.head))
res0: Array[String] = Array(The, dog, fox, the, lazy, over, brown, quick, jumped)```
See also

scala.math.Ordering

Note: will not terminate for infinite-sized collections.

138. def sortWith(lt: (A, A) ⇒ Boolean): LinearSeq[A]

Sorts this sequence according to a comparison function.

Sorts this sequence according to a comparison function.

Note: will not terminate for infinite-sized collections.

The sort is stable. That is, elements that are equal (as determined by `lt`) appear in the same order in the sorted sequence as in the original.

lt

the comparison function which tests whether its first argument precedes its second argument in the desired ordering.

returns

a sequence consisting of the elements of this sequence sorted according to the comparison function `lt`.

Definition Classes
SeqLike
Example:
1. ```List("Steve", "Tom", "John", "Bob").sortWith(_.compareTo(_) < 0) =
List("Bob", "John", "Steve", "Tom")```
139. def sorted[B >: A](implicit ord: math.Ordering[B]): LinearSeq[A]

Sorts this sequence according to an Ordering.

Sorts this sequence according to an Ordering.

The sort is stable. That is, elements that are equal (as determined by `lt`) appear in the same order in the sorted sequence as in the original.

ord

the ordering to be used to compare elements.

returns

a sequence consisting of the elements of this sequence sorted according to the ordering `ord`.

Definition Classes
SeqLike
See also
140. def span(p: (A) ⇒ Boolean): (LinearSeq[A], LinearSeq[A])

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

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

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

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

returns

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

Definition Classes
TraversableLikeGenTraversableLike
141. def splitAt(n: Int): (LinearSeq[A], LinearSeq[A])

Splits this traversable collection into two at a given position.

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

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

n

the position at which to split.

returns

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

Definition Classes
TraversableLikeGenTraversableLike
142. def startsWith[B](that: GenSeq[B], offset: Int): Boolean

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

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

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

that

the sequence to test

offset

the index where the sequence is searched.

returns

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

Definition Classes
SeqLikeGenSeqLike
143. def startsWith[B](that: GenSeq[B]): Boolean

Tests whether this general sequence starts with the given sequence.

Tests whether this general sequence starts with the given sequence.

that

the sequence to test

returns

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

Definition Classes
GenSeqLike
144. def stringPrefix: String

Defines the prefix of this object's `toString` representation.

Defines the prefix of this object's `toString` representation.

returns

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

Definition Classes
TraversableLikeGenTraversableLike
145. def sum: A

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

[use case]

Sums up the elements of this collection.

returns

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

Definition Classes
TraversableOnceGenTraversableOnce
Full Signature

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

Definition Classes
AnyRef
147. def tail: LinearSeq[A]

Selects all elements except the first.

Selects all elements except the first.

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

returns

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

Definition Classes
TraversableLikeGenTraversableLike
Exceptions thrown
`UnsupportedOperationException`

if the traversable collection is empty.

148. def tails: Iterator[LinearSeq[A]]

Iterates over the tails of this traversable collection.

Iterates over the tails of this traversable collection. The first value will be this traversable collection and the final one will be an empty traversable collection, with the intervening values the results of successive applications of `tail`.

returns

an iterator over all the tails of this traversable collection

Definition Classes
TraversableLike
Example:
1. `List(1,2,3).tails = Iterator(List(1,2,3), List(2,3), List(3), Nil)`

149. def take(n: Int): LinearSeq[A]

Selects first n elements.

Selects first n elements.

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

n

the number of elements to take from this iterable collection.

returns

a iterable collection consisting only of the first `n` elements of this iterable collection, or else the whole iterable collection, if it has less than `n` elements.

Definition Classes
IterableLikeTraversableLikeGenTraversableLike
150. def takeRight(n: Int): LinearSeq[A]

Selects last n elements.

Selects last n elements.

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

n

the number of elements to take

returns

a iterable collection consisting only of the last `n` elements of this iterable collection, or else the whole iterable collection, if it has less than `n` elements.

Definition Classes
IterableLike
151. def takeWhile(p: (A) ⇒ Boolean): LinearSeq[A]

Takes longest prefix of elements that satisfy a predicate.

Takes longest prefix of elements that satisfy a predicate.

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

returns

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

Definition Classes
IterableLikeTraversableLikeGenTraversableLike
152. def thisCollection: LinearSeq[A]

The underlying collection seen as an instance of `Seq`.

The underlying collection seen as an instance of `Seq`. By default this is implemented as the current collection object itself, but this can be overridden.

Attributes
protected[this]
Definition Classes
LinearSeqLikeSeqLikeIterableLikeTraversableLike
153. def to[Col[_]]: Col[A]

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

[use case]

Converts this sequence into another by copying all elements.

Note: will not terminate for infinite-sized collections.

Col

The collection type to build.

returns

a new collection containing all elements of this sequence.

Definition Classes
TraversableLikeTraversableOnceGenTraversableOnce
Full Signature

154. def toArray: Array[A]

[use case] Converts this sequence to an array.

[use case]

Converts this sequence to an array.

Note: will not terminate for infinite-sized collections.

returns

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

Definition Classes
TraversableOnceGenTraversableOnce
Full Signature

155. def toBuffer[B >: A]: Buffer[B]

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

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

Note: will not terminate for infinite-sized collections.

returns

a buffer containing all elements of this traversable or iterator.

Definition Classes
TraversableOnceGenTraversableOnce
156. def toCollection(repr: LinearSeq[A]): LinearSeq[A]

A conversion from collections of type `Repr` to `Seq` objects.

A conversion from collections of type `Repr` to `Seq` objects. By default this is implemented as just a cast, but this can be overridden.

Attributes
protected[this]
Definition Classes
LinearSeqLikeSeqLikeIterableLikeTraversableLike
157. def toIndexedSeq: immutable.IndexedSeq[A]

Converts this traversable or iterator to an indexed sequence.

Converts this traversable or iterator to an indexed sequence.

Note: will not terminate for infinite-sized collections.

returns

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

Definition Classes
TraversableOnceGenTraversableOnce
158. def toIterable: Iterable[A]

Returns this iterable collection as an iterable collection.

Returns this iterable collection as an iterable collection.

A new collection will not be built; lazy collections will stay lazy.

Note: will not terminate for infinite-sized collections.

returns

an `Iterable` containing all elements of this iterable collection.

Definition Classes
IterableLikeTraversableOnceGenTraversableOnce
159. def toIterator: Iterator[A]

Returns an Iterator over the elements in this iterable collection.

Returns an Iterator over the elements in this iterable collection. Produces the same result as `iterator`.

Note: will not terminate for infinite-sized collections.

returns

an Iterator containing all elements of this iterable collection.

Definition Classes
IterableLikeTraversableLikeGenTraversableOnce
Annotations
@deprecatedOverriding( ... , "2.11.0" )
160. def toList: List[A]

Converts this traversable or iterator to a list.

Converts this traversable or iterator to a list.

Note: will not terminate for infinite-sized collections.

returns

a list containing all elements of this traversable or iterator.

Definition Classes
TraversableOnceGenTraversableOnce
161. def toMap[T, U]: Map[T, U]

[use case] Converts this sequence to a map.

[use case]

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

Note: will not terminate for infinite-sized collections.

returns

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

Definition Classes
TraversableOnceGenTraversableOnce
Full Signature

162. def toParArray: ParArray[T]

Implicit information
This member is added by an implicit conversion from LinearSeq[A] to CollectionsHaveToParArray[LinearSeq[A], T] performed by method CollectionsHaveToParArray in scala.collection.parallel. This conversion will take place only if an implicit value of type (LinearSeq[A]) ⇒ GenTraversableOnce[T] is in scope.
Definition Classes
CollectionsHaveToParArray
163. def toSeq: Seq[A]

Converts this sequence to a sequence.

Converts this sequence to a sequence.

Note: will not terminate for infinite-sized collections.

A new collection will not be built; in particular, lazy sequences will stay lazy.

returns

a sequence containing all elements of this sequence.

Definition Classes
SeqLikeGenSeqLikeTraversableOnceGenTraversableOnce
164. def toSet[B >: A]: immutable.Set[B]

Converts this traversable or iterator to a set.

Converts this traversable or iterator to a set.

Note: will not terminate for infinite-sized collections.

returns

a set containing all elements of this traversable or iterator.

Definition Classes
TraversableOnceGenTraversableOnce
165. def toStream: immutable.Stream[A]

Converts this iterable collection to a stream.

Converts this iterable collection to a stream.

returns

a stream containing all elements of this iterable collection.

Definition Classes
IterableLikeTraversableLikeGenTraversableOnce
166. def toString(): String

Converts this sequence to a string.

Converts this sequence to a string.

returns

a string representation of this collection. By default this string consists of the `stringPrefix` of this sequence, followed by all elements separated by commas and enclosed in parentheses.

Definition Classes
SeqLikeTraversableLike → Any
167. def toTraversable: Traversable[A]

Converts this traversable collection to an unspecified Traversable.

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

Note: will not terminate for infinite-sized collections.

returns

a Traversable containing all elements of this traversable collection.

Definition Classes
TraversableLikeTraversableOnceGenTraversableOnce
Annotations
@deprecatedOverriding( ... , "2.11.0" )
168. def toVector: Vector[A]

Converts this traversable or iterator to a Vector.

Converts this traversable or iterator to a Vector.

Note: will not terminate for infinite-sized collections.

returns

a vector containing all elements of this traversable or iterator.

Definition Classes
TraversableOnceGenTraversableOnce
169. def transpose[B](implicit asTraversable: (A) ⇒ GenTraversableOnce[B]): LinearSeq[LinearSeq[B]]

Transposes this collection of traversable collections into a collection of collections.

Transposes this collection of traversable collections into a collection of collections.

The resulting collection's type will be guided by the static type of collection. For example:

```val xs = List(
Set(1, 2, 3),
Set(4, 5, 6)).transpose
// xs == List(
//         List(1, 4),
//         List(2, 5),
//         List(3, 6))

val ys = Vector(
List(1, 2, 3),
List(4, 5, 6)).transpose
// ys == Vector(
//         Vector(1, 4),
//         Vector(2, 5),
//         Vector(3, 6))```
B

the type of the elements of each traversable collection.

asTraversable

an implicit conversion which asserts that the element type of this collection is a `Traversable`.

returns

a two-dimensional collection of collections which has as nth row the nth column of this collection.

Definition Classes
GenericTraversableTemplate
Annotations
@migration
Migration

(Changed in version 2.9.0) `transpose` throws an `IllegalArgumentException` if collections are not uniformly sized.

Exceptions thrown
`IllegalArgumentException`

if all collections in this collection are not of the same size.

170. def union(that: Seq[A]): Seq[A]

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

[use case]

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

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

Note: will not terminate for infinite-sized collections.

that

the sequence to add.

returns

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

Definition Classes
SeqLikeGenSeqLike
Full Signature

171. def unzip[A1, A2](implicit asPair: (A) ⇒ (A1, A2)): (LinearSeq[A1], LinearSeq[A2])

Converts this collection of pairs into two collections of the first and second half of each pair.

Converts this collection of pairs into two collections of the first and second half of each pair.

```val xs = CC(
(1, "one"),
(2, "two"),
(3, "three")).unzip
// xs == (CC(1, 2, 3),
//        CC(one, two, three))```
A1

the type of the first half of the element pairs

A2

the type of the second half of the element pairs

asPair

an implicit conversion which asserts that the element type of this collection is a pair.

returns

a pair of collections, containing the first, respectively second half of each element pair of this collection.

Definition Classes
GenericTraversableTemplate
172. def unzip3[A1, A2, A3](implicit asTriple: (A) ⇒ (A1, A2, A3)): (LinearSeq[A1], LinearSeq[A2], LinearSeq[A3])

Converts this collection of triples into three collections of the first, second, and third element of each triple.

Converts this collection of triples into three collections of the first, second, and third element of each triple.

```val xs = CC(
(1, "one", '1'),
(2, "two", '2'),
(3, "three", '3')).unzip3
// xs == (CC(1, 2, 3),
//        CC(one, two, three),
//        CC(1, 2, 3))```
A1

the type of the first member of the element triples

A2

the type of the second member of the element triples

A3

the type of the third member of the element triples

asTriple

an implicit conversion which asserts that the element type of this collection is a triple.

returns

a triple of collections, containing the first, second, respectively third member of each element triple of this collection.

Definition Classes
GenericTraversableTemplate
173. def updated(index: Int, elem: A): Seq[A]

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

[use case]

A copy of this sequence with one single replaced element.

index

the position of the replacement

elem

the replacing element

returns

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

Definition Classes
SeqLikeGenSeqLike
Full Signature

174. def view(from: Int, until: Int): SeqView[A, LinearSeq[A]]

Creates a non-strict view of a slice of this sequence.

Creates a non-strict view of a slice of this sequence.

Note: the difference between `view` and `slice` is that `view` produces a view of the current sequence, whereas `slice` produces a new sequence.

Note: `view(from, to)` is equivalent to `view.slice(from, to)`

from

the index of the first element of the view

until

the index of the element following the view

returns

a non-strict view of a slice of this sequence, starting at index `from` and extending up to (but not including) index `until`.

Definition Classes
SeqLikeIterableLikeTraversableLike
175. def view: SeqView[A, LinearSeq[A]]

Creates a non-strict view of this sequence.

Creates a non-strict view of this sequence.

returns

a non-strict view of this sequence.

Definition Classes
SeqLikeIterableLikeTraversableLike
176. final def wait(): Unit

Definition Classes
AnyRef
Annotations
( ... )
177. final def wait(arg0: Long, arg1: Int): Unit

Definition Classes
AnyRef
Annotations
( ... )
178. final def wait(arg0: Long): Unit

Definition Classes
AnyRef
Annotations
( ... )
179. def withFilter(p: (A) ⇒ Boolean): FilterMonadic[A, LinearSeq[A]]

Creates a non-strict filter of this traversable collection.

Creates a non-strict filter of this traversable collection.

Note: the difference between `c filter p` and `c withFilter p` is that the former creates a new collection, whereas the latter only restricts the domain of subsequent `map`, `flatMap`, `foreach`, and `withFilter` operations.

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

p

the predicate used to test elements.

returns

an object of class `WithFilter`, which supports `map`, `flatMap`, `foreach`, and `withFilter` operations. All these operations apply to those elements of this traversable collection which satisfy the predicate `p`.

Definition Classes
TraversableLikeFilterMonadic
180. def zip[B](that: GenIterable[B]): Seq[(A, B)]

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

[use case]

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

B

the type of the second half of the returned pairs

that

The iterable providing the second half of each result pair

returns

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

Definition Classes
IterableLikeGenIterableLike
Full Signature

181. def zipAll[B](that: Iterable[B], thisElem: A, thatElem: B): Seq[(A, B)]

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

[use case]

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

B

the type of the second half of the returned pairs

that

The iterable providing the second half of each result pair

thisElem

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

thatElem

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

returns

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

Definition Classes
IterableLikeGenIterableLike
Full Signature

182. def zipWithIndex: Seq[(A, Int)]

[use case] Zips this sequence with its indices.

[use case]

Zips this sequence with its indices.

returns

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

Definition Classes
IterableLikeGenIterableLike
Full Signature

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

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

183. def →[B](y: B): (LinearSeq[A], B)

Implicit information
This member is added by an implicit conversion from LinearSeq[A] to ArrowAssoc[LinearSeq[A]] performed by method ArrowAssoc in scala.Predef.
Definition Classes
ArrowAssoc

Shadowed Implicit Value Members

1. def filter(p: (A) ⇒ Boolean): TraversableOnce[A]

Implicit information
This member is added by an implicit conversion from LinearSeq[A] to MonadOps[A] performed by method MonadOps in scala.collection.TraversableOnce.
Shadowing
This implicitly inherited member is shadowed by one or more members in this class.
To access this member you can use a type ascription:
`(linearSeq: MonadOps[A]).filter(p)`
Definition Classes
MonadOps
2. def flatMap[B](f: (A) ⇒ GenTraversableOnce[B]): TraversableOnce[B]

Implicit information
This member is added by an implicit conversion from LinearSeq[A] to MonadOps[A] performed by method MonadOps in scala.collection.TraversableOnce.
Shadowing
This implicitly inherited member is shadowed by one or more members in this class.
To access this member you can use a type ascription:
`(linearSeq: MonadOps[A]).flatMap(f)`
Definition Classes
MonadOps
3. def map[B](f: (A) ⇒ B): TraversableOnce[B]

Implicit information
This member is added by an implicit conversion from LinearSeq[A] to MonadOps[A] performed by method MonadOps in scala.collection.TraversableOnce.
Shadowing
This implicitly inherited member is shadowed by one or more members in this class.
To access this member you can use a type ascription:
`(linearSeq: MonadOps[A]).map(f)`
Definition Classes
MonadOps
4. def withFilter(p: (A) ⇒ Boolean): Iterator[A]

Implicit information
This member is added by an implicit conversion from LinearSeq[A] to MonadOps[A] performed by method MonadOps in scala.collection.TraversableOnce.
Shadowing
This implicitly inherited member is shadowed by one or more members in this class.
To access this member you can use a type ascription:
`(linearSeq: MonadOps[A]).withFilter(p)`
Definition Classes
MonadOps