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scala.collection

TraversableProxyLike

trait TraversableProxyLike[+A, +Repr <: TraversableLike[A, Repr] with Traversable[A]] extends TraversableLike[A, Repr] with Proxy

This trait implements a proxy for Traversable objects. It forwards all calls to a different Traversable object.

Annotations
@deprecated
Deprecated

(Since version 2.11.0) proxying is deprecated due to lack of use and compiler-level support

Source
TraversableProxyLike.scala
Since

2.8

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Inherited
  1. TraversableProxyLike
  2. Proxy
  3. TraversableLike
  4. GenTraversableLike
  5. Parallelizable
  6. TraversableOnce
  7. GenTraversableOnce
  8. FilterMonadic
  9. HasNewBuilder
  10. AnyRef
  11. 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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Visibility
  1. Public
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Type Members

  1. 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
  2. type Self = Repr

    The type implementing this traversable

    The type implementing this traversable

    Attributes
    protected[this]
    Definition Classes
    TraversableLike

Abstract Value Members

  1. abstract def newBuilder: Builder[A, Repr]

    Creates a new builder for this collection type.

    Creates a new builder for this collection type.

    Attributes
    protected[this]
    Definition Classes
    TraversableLikeHasNewBuilder
  2. abstract def self: Repr
    Definition Classes
    TraversableProxyLikeProxy
  3. abstract def seq: TraversableOnce[A]
    Definition Classes
    Parallelizable

Concrete Value Members

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

    Test two objects for inequality.

    Test two objects for inequality.

    returns

    true if !(this == that), false otherwise.

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

    Equivalent to x.hashCode except for boxed numeric types and null.

    Equivalent to x.hashCode except for boxed numeric types and null. For numerics, it returns a hash value which is consistent with value equality: if two value type instances compare as true, then ## will produce the same hash value for each of them. For null returns a hashcode where null.hashCode throws a NullPointerException.

    returns

    a hash value consistent with ==

    Definition Classes
    AnyRef → Any
  3. def +(other: String): String
    Implicit
    This member is added by an implicit conversion from TraversableProxyLike[A, Repr] to any2stringadd[TraversableProxyLike[A, Repr]] performed by method any2stringadd in scala.Predef.
    Definition Classes
    any2stringadd
  4. def ++[B >: A, That](xs: GenTraversableOnce[B])(implicit bf: CanBuildFrom[Repr, B, That]): That

    Returns a new traversable collection containing the elements from the left hand operand followed by the elements from the right hand operand.

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

    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.

    bf

    an implicit value of class CanBuildFrom which determines the result class That from the current representation type Repr 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
    TraversableProxyLikeTraversableLikeGenTraversableLike
  5. def ++:[B >: A, That](that: Traversable[B])(implicit bf: CanBuildFrom[Repr, 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 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]): Traversable[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 traversable collection which contains all elements of this traversable collection followed by all elements of that.

    Definition Classes
    TraversableLike
    Full Signature

    def ++:[B >: A, That](that: TraversableOnce[B])(implicit bf: CanBuildFrom[Repr, B, That]): That

  7. def ->[B](y: B): (TraversableProxyLike[A, Repr], B)
    Implicit
    This member is added by an implicit conversion from TraversableProxyLike[A, Repr] to ArrowAssoc[TraversableProxyLike[A, Repr]] performed by method ArrowAssoc in scala.Predef.
    Definition Classes
    ArrowAssoc
    Annotations
    @inline()
  8. def /:[B](z: B)(op: (B, A) ⇒ B): B

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

    Applies a binary operator to a start value and all elements of this traversable collection, 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 collection, 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 collection.

    Definition Classes
    TraversableProxyLikeTraversableOnceGenTraversableOnce
  9. def :\[B](z: B)(op: (A, B) ⇒ B): B

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

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

    Definition Classes
    TraversableProxyLikeTraversableOnceGenTraversableOnce
  10. final def ==(arg0: Any): Boolean

    The expression x == that is equivalent to if (x eq null) that eq null else x.equals(that).

    The expression x == that is equivalent to if (x eq null) that eq null else x.equals(that).

    returns

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

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

    Appends all elements of this traversable collection to a string builder.

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

    Example:

    scala> val a = List(1,2,3,4)
    a: List[Int] = List(1, 2, 3, 4)
    
    scala> val b = new StringBuilder()
    b: StringBuilder =
    
    scala> val h = a.addString(b)
    h: StringBuilder = 1234
    b

    the string builder to which elements are appended.

    returns

    the string builder b to which elements were appended.

    Definition Classes
    TraversableProxyLikeTraversableOnce
  12. def addString(b: mutable.StringBuilder, sep: String): mutable.StringBuilder

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

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

    Example:

    scala> val a = List(1,2,3,4)
    a: List[Int] = List(1, 2, 3, 4)
    
    scala> val b = new StringBuilder()
    b: StringBuilder =
    
    scala> a.addString(b, ", ")
    res0: StringBuilder = 1, 2, 3, 4
    b

    the string builder to which elements are appended.

    sep

    the separator string.

    returns

    the string builder b to which elements were appended.

    Definition Classes
    TraversableProxyLikeTraversableOnce
  13. def addString(b: mutable.StringBuilder, start: String, sep: String, end: String): mutable.StringBuilder

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

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

    Example:

    scala> val a = List(1,2,3,4)
    a: List[Int] = List(1, 2, 3, 4)
    
    scala> val b = new StringBuilder()
    b: StringBuilder =
    
    scala> a.addString(b , "List(" , ", " , ")")
    res5: StringBuilder = List(1, 2, 3, 4)
    b

    the string builder to which elements are appended.

    start

    the starting string.

    sep

    the separator string.

    end

    the ending string.

    returns

    the string builder b to which elements were appended.

    Definition Classes
    TraversableProxyLikeTraversableOnce
  14. 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 is similar to foldLeft in that it doesn't require the result to be a supertype of the element type. In addition, it allows parallel collections to be processed in chunks, and then combines the intermediate results.

    aggregate splits the traversable or iterator into partitions and processes each partition by sequentially applying seqop, starting with z (like foldLeft). Those intermediate results are then combined by using combop (like fold). The implementation of this operation may operate on an arbitrary number of collection partitions (even 1), so combop may be invoked an arbitrary number of times (even 0).

    As an example, consider summing up the integer values of a list of chars. The initial value for the sum is 0. First, seqop transforms each input character to an Int and adds it to the sum (of the partition). Then, combop just needs to sum up the intermediate results of the partitions:

    List('a', 'b', 'c').aggregate(0)({ (sum, ch) => sum + ch.toInt }, { (p1, p2) => p1 + p2 })
    B

    the type of accumulated results

    z

    the initial value for the accumulated result of the partition - this will typically be the neutral element for the seqop operator (e.g. Nil for list concatenation 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
  15. final def asInstanceOf[T0]: T0

    Cast the receiver object to be of type T0.

    Cast the receiver object to be of type T0.

    Note that the success of a cast at runtime is modulo Scala's erasure semantics. Therefore the expression 1.asInstanceOf[String] will throw a ClassCastException at runtime, while the expression List(1).asInstanceOf[List[String]] will not. In the latter example, because the type argument is erased as part of compilation it is not possible to check whether the contents of the list are of the requested type.

    returns

    the receiver object.

    Definition Classes
    Any
    Exceptions thrown

    ClassCastException if the receiver object is not an instance of the erasure of type T0.

  16. def clone(): AnyRef

    Create a copy of the receiver object.

    Create a copy of the receiver object.

    The default implementation of the clone method is platform dependent.

    returns

    a copy of the receiver object.

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

    not specified by SLS as a member of AnyRef

  17. def collect[B](pf: PartialFunction[A, B]): Traversable[B]

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

    [use case]

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

    B

    the element type of the returned collection.

    pf

    the partial function which filters and maps the traversable collection.

    returns

    a new traversable collection 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
    TraversableProxyLikeTraversableLikeGenTraversableLike
    Full Signature

    def collect[B, That](pf: PartialFunction[A, B])(implicit bf: CanBuildFrom[Repr, B, That]): That

  18. 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)

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

    [use case] Copies the elements of this traversable collection to an array.

    [use case]

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

    Note: will not terminate for infinite-sized collections.

    xs

    the array to fill.

    Definition Classes
    TraversableProxyLikeTraversableOnceGenTraversableOnce
    Full Signature

    def copyToArray[B >: A](xs: Array[B]): Unit

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

    [use case] Copies the elements of this traversable collection to an array.

    [use case]

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

    Note: will not terminate for infinite-sized collections.

    xs

    the array to fill.

    start

    the starting index.

    Definition Classes
    TraversableProxyLikeTraversableOnceGenTraversableOnce
    Full Signature

    def copyToArray[B >: A](xs: Array[B], start: Int): Unit

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

    [use case] Copies the elements of this traversable collection to an array.

    [use case]

    Copies the elements of this traversable collection to an array. Fills the given array xs with at most len elements of this traversable collection, starting at position start. Copying will stop once either the end of the current traversable collection is reached, or the end of the target 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
    TraversableProxyLikeTraversableLikeTraversableOnceGenTraversableOnce
    Full Signature

    def copyToArray[B >: A](xs: Array[B], start: Int, len: Int): Unit

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

    Copies all elements of this traversable collection to a buffer.

    Copies all elements of this traversable collection to a buffer.

    Note: will not terminate for infinite-sized collections.

    dest

    The buffer to which elements are copied.

    Definition Classes
    TraversableProxyLikeTraversableOnce
  23. def count(p: (A) ⇒ Boolean): Int

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

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

    p

    the predicate used to test elements.

    returns

    the number of elements satisfying the predicate p.

    Definition Classes
    TraversableProxyLikeTraversableOnceGenTraversableOnce
  24. def drop(n: Int): Repr

    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 traversable collection.

    returns

    a traversable collection consisting of all elements of this traversable collection except the first n ones, or else the empty traversable collection, if this traversable collection has less than n elements. If n is negative, don't drop any elements.

    Definition Classes
    TraversableProxyLikeTraversableLikeGenTraversableLike
  25. def dropWhile(p: (A) ⇒ Boolean): Repr

    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
    TraversableProxyLikeTraversableLikeGenTraversableLike
  26. def ensuring(cond: (TraversableProxyLike[A, Repr]) ⇒ Boolean, msg: ⇒ Any): TraversableProxyLike[A, Repr]
    Implicit
    This member is added by an implicit conversion from TraversableProxyLike[A, Repr] to Ensuring[TraversableProxyLike[A, Repr]] performed by method Ensuring in scala.Predef.
    Definition Classes
    Ensuring
  27. def ensuring(cond: (TraversableProxyLike[A, Repr]) ⇒ Boolean): TraversableProxyLike[A, Repr]
    Implicit
    This member is added by an implicit conversion from TraversableProxyLike[A, Repr] to Ensuring[TraversableProxyLike[A, Repr]] performed by method Ensuring in scala.Predef.
    Definition Classes
    Ensuring
  28. def ensuring(cond: Boolean, msg: ⇒ Any): TraversableProxyLike[A, Repr]
    Implicit
    This member is added by an implicit conversion from TraversableProxyLike[A, Repr] to Ensuring[TraversableProxyLike[A, Repr]] performed by method Ensuring in scala.Predef.
    Definition Classes
    Ensuring
  29. def ensuring(cond: Boolean): TraversableProxyLike[A, Repr]
    Implicit
    This member is added by an implicit conversion from TraversableProxyLike[A, Repr] to Ensuring[TraversableProxyLike[A, Repr]] performed by method Ensuring in scala.Predef.
    Definition Classes
    Ensuring
  30. final def eq(arg0: AnyRef): Boolean

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

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

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

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

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

    returns

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

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

    Compares the receiver object (this) with the argument object (that) for equivalence.

    Compares the receiver object (this) with the argument object (that) for equivalence.

    Any implementation of this method should be an equivalence relation:

    • It is reflexive: for any instance x of type Any, x.equals(x) should return true.
    • It is symmetric: for any instances x and y of type Any, x.equals(y) should return true if and only if y.equals(x) returns true.
    • It is transitive: for any instances x, y, and z of type Any if x.equals(y) returns true and y.equals(z) returns true, then x.equals(z) should return true.

    If you override this method, you should verify that your implementation remains an equivalence relation. Additionally, when overriding this method it is usually necessary to override hashCode to ensure that objects which are "equal" (o1.equals(o2) returns true) hash to the same scala.Int. (o1.hashCode.equals(o2.hashCode)).

    that

    the object to compare against this object for equality.

    returns

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

    Definition Classes
    ProxyAny
  32. def exists(p: (A) ⇒ Boolean): Boolean

    Tests whether a predicate holds for at least one element of this traversable collection.

    Tests whether a predicate holds for at least one element of this traversable collection.

    Note: may not terminate for infinite-sized collections.

    p

    the predicate used to test elements.

    returns

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

    Definition Classes
    TraversableProxyLikeTraversableLikeTraversableOnceGenTraversableOnce
  33. def filter(p: (A) ⇒ Boolean): Repr

    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
    TraversableProxyLikeTraversableLikeGenTraversableLike
  34. def filterNot(p: (A) ⇒ Boolean): Repr

    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
    TraversableProxyLikeTraversableLikeGenTraversableLike
  35. def finalize(): Unit

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

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

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

    Attributes
    protected[lang]
    Definition Classes
    AnyRef
    Annotations
    @throws( classOf[java.lang.Throwable] )
    Note

    not specified by SLS as a member of AnyRef

  36. def find(p: (A) ⇒ Boolean): Option[A]

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

    Finds the first element of the traversable 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 traversable collection that satisfies p, or None if none exists.

    Definition Classes
    TraversableProxyLikeTraversableLikeTraversableOnceGenTraversableOnce
  37. def flatMap[B](f: (A) ⇒ GenTraversableOnce[B]): Traversable[B]

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

    [use case]

    Builds a new collection by applying a function to all elements of this traversable collection 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 traversable collection. 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 traversable collection resulting from applying the given collection-valued function f to each element of this traversable collection and concatenating the results.

    Definition Classes
    TraversableProxyLikeTraversableLikeGenTraversableLikeFilterMonadic
    Full Signature

    def flatMap[B, That](f: (A) ⇒ GenTraversableOnce[B])(implicit bf: CanBuildFrom[Repr, B, That]): That

  38. 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.

    Note: will not terminate for infinite-sized collections.

    A1

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

    z

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

    op

    a binary operator that must be associative.

    returns

    the result of applying the fold operator op between all the elements and z, or z if this traversable or iterator is empty.

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

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

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

    Note: will not terminate for infinite-sized collections.

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

    B

    the result type of the binary operator.

    z

    the start value.

    op

    the binary operator.

    returns

    the result of inserting op between consecutive elements of this traversable collection, 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 collection. Returns z if this traversable collection is empty.

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

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

    Applies a binary operator to all elements of this traversable 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 traversable 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 traversable collection. Returns z if this traversable collection is empty.

    Definition Classes
    TraversableProxyLikeTraversableOnceGenTraversableOnce
  41. def forall(p: (A) ⇒ Boolean): Boolean

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

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

    Note: may not terminate for infinite-sized collections.

    p

    the predicate used to test elements.

    returns

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

    Definition Classes
    TraversableProxyLikeTraversableLikeTraversableOnceGenTraversableOnce
  42. def foreach(f: (A) ⇒ Unit): Unit

    [use case] Applies a function f to all elements of this traversable collection.

    [use case]

    Applies a function f to all elements of this traversable collection.

    Note: this method underlies the implementation of most other bulk operations. It's important to implement this method in an efficient way.

    f

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

    Definition Classes
    TraversableProxyLikeTraversableLikeGenTraversableLikeTraversableOnceGenTraversableOnceFilterMonadic
    Full Signature

    def foreach[U](f: (A) ⇒ U): Unit

  43. 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
    This member is added by an implicit conversion from TraversableProxyLike[A, Repr] to StringFormat[TraversableProxyLike[A, Repr]] performed by method StringFormat in scala.Predef.
    Definition Classes
    StringFormat
    Annotations
    @inline()
  44. final def getClass(): Class[_]

    Returns the runtime class representation of the object.

    Returns the runtime class representation of the object.

    returns

    a class object corresponding to the runtime type of the receiver.

    Definition Classes
    AnyRef → Any
    Annotations
    @native()
  45. def groupBy[K](f: (A) ⇒ K): immutable.Map[K, Repr]

    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
    TraversableProxyLikeTraversableLikeGenTraversableLike
  46. 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. Non-empty Iterators usually return false even if they were created from a collection with a known finite size.

    Note: many collection methods will not work on collections of infinite sizes. The typical failure mode is an infinite loop. These methods always attempt a traversal without checking first that hasDefiniteSize returns true. However, checking hasDefiniteSize can provide an assurance that size is well-defined and non-termination is not a concern.

    returns

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

    Definition Classes
    TraversableProxyLikeTraversableLikeTraversableOnceGenTraversableOnce
  47. def hashCode(): Int

    Calculate a hash code value for the object.

    Calculate a hash code value for the object.

    The default hashing algorithm is platform dependent.

    Note that it is allowed for two objects to have identical hash codes (o1.hashCode.equals(o2.hashCode)) yet not be equal (o1.equals(o2) returns false). A degenerate implementation could always return 0. However, it is required that if two objects are equal (o1.equals(o2) returns true) that they have identical hash codes (o1.hashCode.equals(o2.hashCode)). Therefore, when overriding this method, be sure to verify that the behavior is consistent with the equals method.

    returns

    the hash code value for this object.

    Definition Classes
    ProxyAny
  48. def head: A

    Selects the first element of this traversable collection.

    Selects the first element of this traversable collection.

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

    returns

    the first element of this traversable collection.

    Definition Classes
    TraversableProxyLikeTraversableLikeGenTraversableLike
    Exceptions thrown

    NoSuchElementException if the traversable collection is empty.

  49. 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
    TraversableProxyLikeTraversableLikeGenTraversableLike
  50. def init: Repr

    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
    TraversableProxyLikeTraversableLikeGenTraversableLike
    Exceptions thrown

    UnsupportedOperationException if the traversable collection is empty.

  51. def inits: Iterator[Repr]

    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)

  52. def isEmpty: Boolean

    Tests whether this traversable collection is empty.

    Tests whether this traversable collection is empty.

    returns

    true if the traversable collection contain no elements, false otherwise.

    Definition Classes
    TraversableProxyLikeTraversableLikeTraversableOnceGenTraversableOnce
  53. final def isInstanceOf[T0]: Boolean

    Test whether the dynamic type of the receiver object is T0.

    Test whether the dynamic type of the receiver object is T0.

    Note that the result of the test is modulo Scala's erasure semantics. Therefore the expression 1.isInstanceOf[String] will return false, while the expression List(1).isInstanceOf[List[String]] will return true. In the latter example, because the type argument is erased as part of compilation it is not possible to check whether the contents of the list are of the specified type.

    returns

    true if the receiver object is an instance of erasure of type T0; false otherwise.

    Definition Classes
    Any
  54. 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
  55. 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
    TraversableProxyLikeTraversableLikeGenTraversableLike
    Exceptions thrown

    NoSuchElementException If the traversable collection is empty.

  56. 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
    TraversableProxyLikeTraversableLikeGenTraversableLike
  57. def map[B](f: (A) ⇒ B): Traversable[B]

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

    [use case]

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

    B

    the element type of the returned collection.

    f

    the function to apply to each element.

    returns

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

    Definition Classes
    TraversableProxyLikeTraversableLikeGenTraversableLikeFilterMonadic
    Full Signature

    def map[B, That](f: (A) ⇒ B)(implicit bf: CanBuildFrom[Repr, B, That]): That

  58. def max: A

    [use case] Finds the largest element.

    [use case]

    Finds the largest element.

    returns

    the largest element of this traversable collection.

    Definition Classes
    TraversableProxyLikeTraversableOnceGenTraversableOnce
    Full Signature

    def max[B >: A](implicit cmp: Ordering[B]): A

    Exceptions thrown

    UnsupportedOperationException if this traversable collection is empty.

  59. def maxBy[B](f: (A) ⇒ B): A

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

    [use case]

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

    B

    The result type of the function f.

    f

    The measuring function.

    returns

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

    Definition Classes
    TraversableOnceGenTraversableOnce
    Full Signature

    def maxBy[B](f: (A) ⇒ B)(implicit cmp: Ordering[B]): A

    Exceptions thrown

    UnsupportedOperationException if this traversable collection is empty.

  60. def min: A

    [use case] Finds the smallest element.

    [use case]

    Finds the smallest element.

    returns

    the smallest element of this traversable collection

    Definition Classes
    TraversableProxyLikeTraversableOnceGenTraversableOnce
    Full Signature

    def min[B >: A](implicit cmp: Ordering[B]): A

    Exceptions thrown

    UnsupportedOperationException if this traversable collection is empty.

  61. def minBy[B](f: (A) ⇒ B): A

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

    [use case]

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

    B

    The result type of the function f.

    f

    The measuring function.

    returns

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

    Definition Classes
    TraversableOnceGenTraversableOnce
    Full Signature

    def minBy[B](f: (A) ⇒ B)(implicit cmp: Ordering[B]): A

    Exceptions thrown

    UnsupportedOperationException if this traversable collection is empty.

  62. def mkString: String

    Displays all elements of this traversable collection in a string.

    Displays all elements of this traversable collection in a string.

    returns

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

    Definition Classes
    TraversableProxyLikeTraversableOnceGenTraversableOnce
  63. def mkString(sep: String): String

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

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

    sep

    the separator string.

    returns

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

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

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

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

    Displays all elements of this traversable collection 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 collection. 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 collection are separated by the string sep.

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

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

    Equivalent to !(this eq that).

    Equivalent to !(this eq that).

    returns

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

    Definition Classes
    AnyRef
  66. def nonEmpty: Boolean

    Tests whether the traversable collection is not empty.

    Tests whether the traversable collection is not empty.

    returns

    true if the traversable collection contains at least one element, false otherwise.

    Definition Classes
    TraversableProxyLikeTraversableOnceGenTraversableOnce
  67. final def notify(): Unit

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

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

    Definition Classes
    AnyRef
    Annotations
    @native()
    Note

    not specified by SLS as a member of AnyRef

  68. final def notifyAll(): Unit

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

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

    Definition Classes
    AnyRef
    Annotations
    @native()
    Note

    not specified by SLS as a member of AnyRef

  69. def par: ParIterable[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
  70. def parCombiner: Combiner[A, ParIterable[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
    TraversableLikeParallelizable
  71. def partition(p: (A) ⇒ Boolean): (Repr, Repr)

    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
    TraversableProxyLikeTraversableLikeGenTraversableLike
  72. def product: A

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

    [use case]

    Multiplies up the elements of this collection.

    returns

    the product of all elements in this traversable collection 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 traversable collection and as result type of product. Examples of such types are: Long, Float, Double, BigInt.

    Definition Classes
    TraversableProxyLikeTraversableOnceGenTraversableOnce
    Full Signature

    def product[B >: A](implicit num: Numeric[B]): B

  73. 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.

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

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

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

    Note: will not terminate for infinite-sized collections.

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

    B

    the result type of the binary operator.

    op

    the binary operator.

    returns

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

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

    where x1, ..., xn are the elements of this traversable collection.

    Definition Classes
    TraversableProxyLikeTraversableOnce
    Exceptions thrown

    UnsupportedOperationException if this traversable collection is empty.

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

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

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

    Note: will not terminate for infinite-sized collections.

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

    B

    the result type of the binary operator.

    op

    the binary operator.

    returns

    an option value containing the result of reduceLeft(op) if this traversable collection is nonempty, None otherwise.

    Definition Classes
    TraversableProxyLikeTraversableOnceGenTraversableOnce
  76. 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
  77. def reduceRight[B >: A](op: (A, B) ⇒ B): B

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

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

    Definition Classes
    TraversableProxyLikeTraversableOnceGenTraversableOnce
    Exceptions thrown

    UnsupportedOperationException if this traversable collection is empty.

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

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

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

    Note: will not terminate for infinite-sized collections.

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

    B

    the result type of the binary operator.

    op

    the binary operator.

    returns

    an option value containing the result of reduceRight(op) if this traversable collection is nonempty, None otherwise.

    Definition Classes
    TraversableProxyLikeTraversableOnceGenTraversableOnce
  79. def repr: Repr

    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
  80. def reversed: List[A]
    Attributes
    protected[this]
    Definition Classes
    TraversableOnce
  81. def scan[B >: A, That](z: B)(op: (B, B) ⇒ B)(implicit cbf: CanBuildFrom[Repr, 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
  82. def scanLeft[B, That](z: B)(op: (B, A) ⇒ B)(implicit bf: CanBuildFrom[Repr, 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 the new element type B.

    returns

    collection with intermediate results

    Definition Classes
    TraversableProxyLikeTraversableLikeGenTraversableLike
  83. def scanRight[B, That](z: B)(op: (A, B) ⇒ B)(implicit bf: CanBuildFrom[Repr, 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 the new element type B.

    returns

    collection with intermediate results

    Definition Classes
    TraversableProxyLikeTraversableLikeGenTraversableLike
  84. def size: Int

    The size of this traversable collection.

    The size of this traversable collection.

    Note: will not terminate for infinite-sized collections.

    returns

    the number of elements in this traversable collection.

    Definition Classes
    TraversableProxyLikeGenTraversableLikeTraversableOnceGenTraversableOnce
  85. def sizeHintIfCheap: Int

    The size of this collection or iterator, if it can be cheaply computed

    The size of this collection or iterator, if it can be cheaply computed

    returns

    the number of elements in this collection or iterator, or -1 if the size cannot be determined cheaply

    Attributes
    protected[collection]
    Definition Classes
    GenTraversableOnce
  86. def slice(from: Int, until: Int): Repr

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

    Definition Classes
    TraversableProxyLikeTraversableLikeGenTraversableLike
  87. def span(p: (A) ⇒ Boolean): (Repr, Repr)

    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
    TraversableProxyLikeTraversableLikeGenTraversableLike
  88. def splitAt(n: Int): (Repr, Repr)

    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
    TraversableProxyLikeTraversableLikeGenTraversableLike
  89. 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
    TraversableProxyLikeTraversableLikeGenTraversableLike
  90. def sum: A

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

    [use case]

    Sums up the elements of this collection.

    returns

    the sum of all elements in this traversable collection 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 traversable collection and as result type of sum. Examples of such types are: Long, Float, Double, BigInt.

    Definition Classes
    TraversableProxyLikeTraversableOnceGenTraversableOnce
    Full Signature

    def sum[B >: A](implicit num: Numeric[B]): B

  91. final def synchronized[T0](arg0: ⇒ T0): T0
    Definition Classes
    AnyRef
  92. def tail: Repr

    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
    TraversableProxyLikeTraversableLikeGenTraversableLike
    Exceptions thrown

    java.lang.UnsupportedOperationException if the traversable collection is empty.

  93. def tails: Iterator[Repr]

    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)

  94. def take(n: Int): Repr

    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 traversable collection.

    returns

    a traversable collection consisting only of the first n elements of this traversable collection, or else the whole traversable collection, if it has less than n elements. If n is negative, returns an empty traversable collection.

    Definition Classes
    TraversableProxyLikeTraversableLikeGenTraversableLike
  95. def takeWhile(p: (A) ⇒ Boolean): Repr

    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 traversable collection whose elements all satisfy the predicate p.

    Definition Classes
    TraversableProxyLikeTraversableLikeGenTraversableLike
  96. def thisCollection: Traversable[A]

    The underlying collection seen as an instance of Traversable.

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

    Attributes
    protected[this]
    Definition Classes
    TraversableLike
  97. def to[Col[_]]: Col[A]

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

    [use case]

    Converts this traversable collection 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 traversable collection.

    Definition Classes
    TraversableLikeTraversableOnceGenTraversableOnce
    Full Signature

    def to[Col[_]](implicit cbf: CanBuildFrom[Nothing, A, Col[A]]): Col[A]

  98. def toArray: Array[A]

    [use case] Converts this traversable collection to an array.

    [use case]

    Converts this traversable collection to an array.

    Note: will not terminate for infinite-sized collections.

    returns

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

    Definition Classes
    TraversableProxyLikeTraversableOnceGenTraversableOnce
    Full Signature

    def toArray[B >: A](implicit arg0: ClassTag[B]): Array[B]

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

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

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

    Note: will not terminate for infinite-sized collections.

    returns

    a buffer containing all elements of this traversable collection.

    Definition Classes
    TraversableProxyLikeTraversableOnceGenTraversableOnce
  100. def toCollection(repr: Repr): Traversable[A]

    A conversion from collections of type Repr to Traversable objects.

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

    Attributes
    protected[this]
    Definition Classes
    TraversableLike
  101. def toIndexedSeq: immutable.IndexedSeq[A]

    Converts this traversable collection to an indexed sequence.

    Converts this traversable collection to an indexed sequence.

    Note: will not terminate for infinite-sized collections.

    returns

    an indexed sequence containing all elements of this traversable collection.

    Definition Classes
    TraversableProxyLikeTraversableOnceGenTraversableOnce
  102. def toIterable: Iterable[A]

    Converts this traversable collection to an iterable collection.

    Converts this traversable collection to an iterable collection. Note that the choice of target Iterable is lazy in this default implementation as this TraversableOnce may be lazy and unevaluated (i.e. it may be an iterator which is only traversable once).

    Note: will not terminate for infinite-sized collections.

    returns

    an Iterable containing all elements of this traversable collection.

    Definition Classes
    TraversableProxyLikeTraversableOnceGenTraversableOnce
  103. def toIterator: Iterator[A]

    Returns an Iterator over the elements in this traversable collection.

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

    Note: will not terminate for infinite-sized collections.

    returns

    an Iterator containing all elements of this traversable collection.

    Definition Classes
    TraversableProxyLikeTraversableLikeGenTraversableOnce
  104. def toList: List[A]

    Converts this traversable collection to a list.

    Converts this traversable collection to a list.

    Note: will not terminate for infinite-sized collections.

    returns

    a list containing all elements of this traversable collection.

    Definition Classes
    TraversableProxyLikeTraversableOnceGenTraversableOnce
  105. def toMap[T, U]: Map[T, U]

    [use case] Converts this traversable collection to a map.

    [use case]

    Converts this traversable collection 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 traversable collection.

    Definition Classes
    TraversableProxyLikeTraversableOnceGenTraversableOnce
    Full Signature

    def toMap[T, U](implicit ev: <:<[A, (T, U)]): immutable.Map[T, U]

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

    Converts this traversable collection to a sequence.

    Converts this traversable collection to a sequence. As with toIterable, it's lazy in this default implementation, as this TraversableOnce may be lazy and unevaluated.

    Note: will not terminate for infinite-sized collections.

    returns

    a sequence containing all elements of this traversable collection.

    Definition Classes
    TraversableProxyLikeTraversableOnceGenTraversableOnce
  108. def toSet[B >: A]: immutable.Set[B]

    Converts this traversable collection to a set.

    Converts this traversable collection to a set.

    Note: will not terminate for infinite-sized collections.

    returns

    a set containing all elements of this traversable collection.

    Definition Classes
    TraversableProxyLikeTraversableOnceGenTraversableOnce
  109. def toStream: Stream[A]

    Converts this traversable collection to a stream.

    Converts this traversable collection to a stream.

    returns

    a stream containing all elements of this traversable collection.

    Definition Classes
    TraversableProxyLikeTraversableLikeGenTraversableOnce
  110. def toString(): String

    Returns a string representation of the object.

    Returns a string representation of the object.

    The default representation is platform dependent.

    returns

    a string representation of the object.

    Definition Classes
    ProxyAny
  111. 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
    TraversableProxyLikeTraversableLikeTraversableOnceGenTraversableOnce
  112. 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
  113. def view(from: Int, until: Int): TraversableView[A, Repr]

    Creates a non-strict view of a slice of this traversable collection.

    Creates a non-strict view of a slice of this traversable collection.

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

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

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

    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 traversable collection, starting at index from and extending up to (but not including) index until.

    Definition Classes
    TraversableProxyLikeTraversableLike
  114. def view: TraversableView[A, Repr]

    Creates a non-strict view of this traversable collection.

    Creates a non-strict view of this traversable collection.

    returns

    a non-strict view of this traversable collection.

    Definition Classes
    TraversableProxyLikeTraversableLike
  115. final def wait(): Unit
    Definition Classes
    AnyRef
    Annotations
    @throws( ... )
  116. final def wait(arg0: Long, arg1: Int): Unit
    Definition Classes
    AnyRef
    Annotations
    @throws( ... )
  117. final def wait(arg0: Long): Unit
    Definition Classes
    AnyRef
    Annotations
    @throws( ... ) @native()
  118. def withFilter(p: (A) ⇒ Boolean): FilterMonadic[A, Repr]

    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
  119. def [B](y: B): (TraversableProxyLike[A, Repr], B)
    Implicit
    This member is added by an implicit conversion from TraversableProxyLike[A, Repr] to ArrowAssoc[TraversableProxyLike[A, Repr]] performed by method ArrowAssoc in scala.Predef.
    Definition Classes
    ArrowAssoc

Shadowed Implicit Value Members

  1. def filter(p: (A) ⇒ Boolean): TraversableOnce[A]
    Implicit
    This member is added by an implicit conversion from TraversableProxyLike[A, Repr] 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:
    (traversableProxyLike: MonadOps[A]).filter(p)
    Definition Classes
    MonadOps
  2. def flatMap[B](f: (A) ⇒ GenTraversableOnce[B]): TraversableOnce[B]
    Implicit
    This member is added by an implicit conversion from TraversableProxyLike[A, Repr] 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:
    (traversableProxyLike: MonadOps[A]).flatMap(f)
    Definition Classes
    MonadOps
  3. def map[B](f: (A) ⇒ B): TraversableOnce[B]
    Implicit
    This member is added by an implicit conversion from TraversableProxyLike[A, Repr] 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:
    (traversableProxyLike: MonadOps[A]).map(f)
    Definition Classes
    MonadOps
  4. def withFilter(p: (A) ⇒ Boolean): Iterator[A]
    Implicit
    This member is added by an implicit conversion from TraversableProxyLike[A, Repr] 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:
    (traversableProxyLike: MonadOps[A]).withFilter(p)
    Definition Classes
    MonadOps

Inherited from Proxy

Inherited from TraversableLike[A, Repr]

Inherited from GenTraversableLike[A, Repr]

Inherited from Parallelizable[A, ParIterable[A]]

Inherited from TraversableOnce[A]

Inherited from GenTraversableOnce[A]

Inherited from FilterMonadic[A, Repr]

Inherited from HasNewBuilder[A, Repr]

Inherited from AnyRef

Inherited from Any

Inherited by implicit conversion CollectionsHaveToParArray from TraversableProxyLike[A, Repr] to CollectionsHaveToParArray[TraversableProxyLike[A, Repr], T]

Inherited by implicit conversion MonadOps from TraversableProxyLike[A, Repr] to MonadOps[A]

Inherited by implicit conversion any2stringadd from TraversableProxyLike[A, Repr] to any2stringadd[TraversableProxyLike[A, Repr]]

Inherited by implicit conversion StringFormat from TraversableProxyLike[A, Repr] to StringFormat[TraversableProxyLike[A, Repr]]

Inherited by implicit conversion Ensuring from TraversableProxyLike[A, Repr] to Ensuring[TraversableProxyLike[A, Repr]]

Inherited by implicit conversion ArrowAssoc from TraversableProxyLike[A, Repr] to ArrowAssoc[TraversableProxyLike[A, Repr]]

Inherited by implicit conversion alternateImplicit from TraversableProxyLike[A, Repr] to ForceImplicitAmbiguity

Ungrouped