scala.runtime.ZippedTraversable2

trait ZippedTraversable2[+El1, +El2] extends Any

This interface is intended as a minimal interface, not complicated by the requirement to resolve type constructors, for implicit search (which only needs to find an implicit conversion to Traversable for our purposes.)

Abstract Value Members From scala.runtime.ZippedTraversable2

abstract def foreach[U](f: (El1, El2) ⇒ U): Unit

(defined at scala.runtime.ZippedTraversable2)


Concrete Value Members From Implicit scala.runtime.ZippedTraversable2.zippedTraversable2ToTraversable ——————————————————————————–

def ++:[B >: A, That](that: collection.Traversable[B])(implicit bf: CanBuildFrom[collection.Traversable[(El1, El2)], B, That]): That

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 collection followed by all elements of that .
  • Implicit information
    • This member is added by an implicit conversion from ZippedTraversable2 [El1, El2] to Traversable [(El1, El2)] performed by method zippedTraversable2ToTraversable in scala.runtime.ZippedTraversable2.
  • Definition Classes
    • TraversableLike

(added by implicit convertion: scala.runtime.ZippedTraversable2.zippedTraversable2ToTraversable)

def ++:[B >: A, That](that: collection.TraversableOnce[B])(implicit bf: CanBuildFrom[collection.Traversable[(El1, El2)], B, That]): That

[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 collection which contains all elements of this collection followed by all elements of that .
  • Implicit information
    • This member is added by an implicit conversion from ZippedTraversable2 [El1, El2] to Traversable [(El1, El2)] performed by method zippedTraversable2ToTraversable in scala.runtime.ZippedTraversable2.
  • Definition Classes
    • TraversableLike

(added by implicit convertion: scala.runtime.ZippedTraversable2.zippedTraversable2ToTraversable)

def ++[B >: A, That](that: GenTraversableOnce[B])(implicit bf: CanBuildFrom[collection.Traversable[(El1, El2)], B, That]): That

[use case]

Returns a new collection containing the elements from the left hand operand followed by the elements from the right hand operand. The element type of the collection 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 collection which contains all elements of this collection followed by all elements of that .
  • Implicit information
    • This member is added by an implicit conversion from ZippedTraversable2 [El1, El2] to Traversable [(El1, El2)] performed by method zippedTraversable2ToTraversable in scala.runtime.ZippedTraversable2.
  • Definition Classes
    • TraversableLike → GenTraversableLike

(added by implicit convertion: scala.runtime.ZippedTraversable2.zippedTraversable2ToTraversable)

def /:[B](z: B)(op: (B, (El1, El2)) ⇒ B): B

Applies a binary operator to a start value and all elements of this 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 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 collection.
  • Implicit information
    • This member is added by an implicit conversion from ZippedTraversable2 [El1, El2] to Traversable [(El1, El2)] performed by method zippedTraversable2ToTraversable in scala.runtime.ZippedTraversable2.
  • Definition Classes
    • TraversableOnce → GenTraversableOnce

(added by implicit convertion: scala.runtime.ZippedTraversable2.zippedTraversable2ToTraversable)

def :\[B](z: B)(op: ((El1, El2), B) ⇒ B): B

Applies a binary operator to all elements of this 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 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 collection.
  • Implicit information
    • This member is added by an implicit conversion from ZippedTraversable2 [El1, El2] to Traversable [(El1, El2)] performed by method zippedTraversable2ToTraversable in scala.runtime.ZippedTraversable2.
  • Definition Classes
    • TraversableOnce → GenTraversableOnce

(added by implicit convertion: scala.runtime.ZippedTraversable2.zippedTraversable2ToTraversable)

def addString(b: StringBuilder): StringBuilder

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

Example:

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

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

scala> val h = a.addString(b)
h: StringBuilder = 1234
  • b
    • the string builder to which elements are appended.
  • returns
    • the string builder b to which elements were appended.
  • Implicit information
    • This member is added by an implicit conversion from ZippedTraversable2 [El1, El2] to Traversable [(El1, El2)] performed by method zippedTraversable2ToTraversable in scala.runtime.ZippedTraversable2.
  • Definition Classes
    • TraversableOnce

(added by implicit convertion: scala.runtime.ZippedTraversable2.zippedTraversable2ToTraversable)

def addString(b: StringBuilder, sep: String): StringBuilder

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

Example:

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

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

scala> a.addString(b, ", ")
res0: StringBuilder = 1, 2, 3, 4
  • b
    • the string builder to which elements are appended.
  • sep
    • the separator string.
  • returns
    • the string builder b to which elements were appended.
  • Implicit information
    • This member is added by an implicit conversion from ZippedTraversable2 [El1, El2] to Traversable [(El1, El2)] performed by method zippedTraversable2ToTraversable in scala.runtime.ZippedTraversable2.
  • Definition Classes
    • TraversableOnce

(added by implicit convertion: scala.runtime.ZippedTraversable2.zippedTraversable2ToTraversable)

def addString(b: StringBuilder, start: String, sep: String, end: String): StringBuilder

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

Example:

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

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

scala> a.addString(b , "List(" , ", " , ")")
res5: StringBuilder = List(1, 2, 3, 4)
  • b
    • the string builder to which elements are appended.
  • start
    • the starting string.
  • sep
    • the separator string.
  • end
    • the ending string.
  • returns
    • the string builder b to which elements were appended.
  • Implicit information
    • This member is added by an implicit conversion from ZippedTraversable2 [El1, El2] to Traversable [(El1, El2)] performed by method zippedTraversable2ToTraversable in scala.runtime.ZippedTraversable2.
  • Definition Classes
    • TraversableOnce

(added by implicit convertion: scala.runtime.ZippedTraversable2.zippedTraversable2ToTraversable)

def aggregate[B](z: ⇒ B)(seqop: (B, (El1, El2)) ⇒ B, combop: (B, B) ⇒ B): B

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 collection 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
  • Implicit information
    • This member is added by an implicit conversion from ZippedTraversable2 [El1, El2] to Traversable [(El1, El2)] performed by method zippedTraversable2ToTraversable in scala.runtime.ZippedTraversable2.
  • Definition Classes
    • TraversableOnce → GenTraversableOnce

(added by implicit convertion: scala.runtime.ZippedTraversable2.zippedTraversable2ToTraversable)

def collectFirst[B](pf: PartialFunction[(El1, El2), B]): Option[B]

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

Note: may not terminate for infinite-sized collections.

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

  • pf
    • the partial function
  • returns
    • an option value containing pf applied to the first value for which it is defined, or None if none exists.
  • Implicit information
    • This member is added by an implicit conversion from ZippedTraversable2 [El1, El2] to Traversable [(El1, El2)] performed by method zippedTraversable2ToTraversable in scala.runtime.ZippedTraversable2.
  • Definition Classes
    • TraversableOnce

Example:

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

(added by implicit convertion: scala.runtime.ZippedTraversable2.zippedTraversable2ToTraversable)

def collect[B, That](pf: PartialFunction[(El1, El2), B])(implicit bf: CanBuildFrom[collection.Traversable[(El1, El2)], B, That]): That

[use case]

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

  • B
    • the element type of the returned collection.
  • pf
    • the partial function which filters and maps the collection.
  • returns
    • a new 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.
  • Implicit information
    • This member is added by an implicit conversion from ZippedTraversable2 [El1, El2] to Traversable [(El1, El2)] performed by method zippedTraversable2ToTraversable in scala.runtime.ZippedTraversable2.
  • Definition Classes
    • TraversableLike → GenTraversableLike

(added by implicit convertion: scala.runtime.ZippedTraversable2.zippedTraversable2ToTraversable)

def companion: GenericCompanion[collection.Traversable]

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

  • Implicit information
    • This member is added by an implicit conversion from ZippedTraversable2 [El1, El2] to Traversable [(El1, El2)] performed by method zippedTraversable2ToTraversable in scala.runtime.ZippedTraversable2.
  • Definition Classes
    • Traversable → GenTraversable → GenericTraversableTemplate

(added by implicit convertion: scala.runtime.ZippedTraversable2.zippedTraversable2ToTraversable)

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

[use case]

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

  • xs
    • the array to fill.
  • Implicit information
    • This member is added by an implicit conversion from ZippedTraversable2 [El1, El2] to Traversable [(El1, El2)] performed by method zippedTraversable2ToTraversable in scala.runtime.ZippedTraversable2.
  • Definition Classes
    • TraversableOnce → GenTraversableOnce

(added by implicit convertion: scala.runtime.ZippedTraversable2.zippedTraversable2ToTraversable)

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

[use case]

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

  • xs
    • the array to fill.
  • start
    • the starting index.
  • Implicit information
    • This member is added by an implicit conversion from ZippedTraversable2 [El1, El2] to Traversable [(El1, El2)] performed by method zippedTraversable2ToTraversable in scala.runtime.ZippedTraversable2.
  • Definition Classes
    • TraversableOnce → GenTraversableOnce

(added by implicit convertion: scala.runtime.ZippedTraversable2.zippedTraversable2ToTraversable)

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

[use case]

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

  • xs
    • the array to fill.
  • start
    • the starting index.
  • len
    • the maximal number of elements to copy.
  • Implicit information
    • This member is added by an implicit conversion from ZippedTraversable2 [El1, El2] to Traversable [(El1, El2)] performed by method zippedTraversable2ToTraversable in scala.runtime.ZippedTraversable2.
  • Definition Classes
    • TraversableLike → TraversableOnce → GenTraversableOnce

(added by implicit convertion: scala.runtime.ZippedTraversable2.zippedTraversable2ToTraversable)

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

Copies all elements of this collection to a buffer.

Note: will not terminate for infinite-sized collections.

  • dest
    • The buffer to which elements are copied.
  • Implicit information
    • This member is added by an implicit conversion from ZippedTraversable2 [El1, El2] to Traversable [(El1, El2)] performed by method zippedTraversable2ToTraversable in scala.runtime.ZippedTraversable2.
  • Definition Classes
    • TraversableOnce

(added by implicit convertion: scala.runtime.ZippedTraversable2.zippedTraversable2ToTraversable)

def count(p: ((El1, El2)) ⇒ Boolean): Int

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

  • p
    • the predicate used to test elements.
  • returns
    • the number of elements satisfying the predicate p .
  • Implicit information
    • This member is added by an implicit conversion from ZippedTraversable2 [El1, El2] to Traversable [(El1, El2)] performed by method zippedTraversable2ToTraversable in scala.runtime.ZippedTraversable2.
  • Definition Classes
    • TraversableOnce → GenTraversableOnce

(added by implicit convertion: scala.runtime.ZippedTraversable2.zippedTraversable2ToTraversable)

def drop(n: Int): collection.Traversable[(El1, El2)]

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 collection.
  • returns
    • a collection consisting of all elements of this collection except the first n ones, or else the empty collection, if this collection has less than n elements.
  • Implicit information
    • This member is added by an implicit conversion from ZippedTraversable2 [El1, El2] to Traversable [(El1, El2)] performed by method zippedTraversable2ToTraversable in scala.runtime.ZippedTraversable2.
  • Definition Classes
    • TraversableLike → GenTraversableLike

(added by implicit convertion: scala.runtime.ZippedTraversable2.zippedTraversable2ToTraversable)

def dropWhile(p: ((El1, El2)) ⇒ Boolean): collection.Traversable[(El1, El2)]

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 collection whose first element does not satisfy the predicate p .
  • Implicit information
    • This member is added by an implicit conversion from ZippedTraversable2 [El1, El2] to Traversable [(El1, El2)] performed by method zippedTraversable2ToTraversable in scala.runtime.ZippedTraversable2.
  • Definition Classes
    • TraversableLike → GenTraversableLike

(added by implicit convertion: scala.runtime.ZippedTraversable2.zippedTraversable2ToTraversable)

def exists(p: ((El1, El2)) ⇒ Boolean): Boolean

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

Note: may not terminate for infinite-sized collections.

  • p
    • the predicate used to test elements.
  • returns
    • false if this collection is empty, otherwise true if the given predicate p holds for some of the elements of this collection, otherwise false
  • Implicit information
    • This member is added by an implicit conversion from ZippedTraversable2 [El1, El2] to Traversable [(El1, El2)] performed by method zippedTraversable2ToTraversable in scala.runtime.ZippedTraversable2.
  • Definition Classes
    • TraversableLike → TraversableOnce → GenTraversableOnce

(added by implicit convertion: scala.runtime.ZippedTraversable2.zippedTraversable2ToTraversable)

def filter(p: ((El1, El2)) ⇒ Boolean): collection.Traversable[(El1, El2)]

Selects all elements of this collection which satisfy a predicate.

  • p
    • the predicate used to test elements.
  • returns
    • a new collection consisting of all elements of this collection that satisfy the given predicate p . The order of the elements is preserved.
  • Implicit information
    • This member is added by an implicit conversion from ZippedTraversable2 [El1, El2] to Traversable [(El1, El2)] performed by method zippedTraversable2ToTraversable in scala.runtime.ZippedTraversable2.
  • Definition Classes
    • TraversableLike → GenTraversableLike

(added by implicit convertion: scala.runtime.ZippedTraversable2.zippedTraversable2ToTraversable)

def filterNot(p: ((El1, El2)) ⇒ Boolean): collection.Traversable[(El1, El2)]

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

  • p
    • the predicate used to test elements.
  • returns
    • a new collection consisting of all elements of this collection that do not satisfy the given predicate p . The order of the elements is preserved.
  • Implicit information
    • This member is added by an implicit conversion from ZippedTraversable2 [El1, El2] to Traversable [(El1, El2)] performed by method zippedTraversable2ToTraversable in scala.runtime.ZippedTraversable2.
  • Definition Classes
    • TraversableLike → GenTraversableLike

(added by implicit convertion: scala.runtime.ZippedTraversable2.zippedTraversable2ToTraversable)

def find(p: ((El1, El2)) ⇒ Boolean): Option[(El1, El2)]

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

Note: may not terminate for infinite-sized collections.

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

  • p
    • the predicate used to test elements.
  • returns
    • an option value containing the first element in the collection that satisfies p , or None if none exists.
  • Implicit information
    • This member is added by an implicit conversion from ZippedTraversable2 [El1, El2] to Traversable [(El1, El2)] performed by method zippedTraversable2ToTraversable in scala.runtime.ZippedTraversable2.
  • Definition Classes
    • TraversableLike → TraversableOnce → GenTraversableOnce

(added by implicit convertion: scala.runtime.ZippedTraversable2.zippedTraversable2ToTraversable)

def flatMap[B, That](f: ((El1, El2)) ⇒ GenTraversableOnce[B])(implicit bf: CanBuildFrom[collection.Traversable[(El1, El2)], B, That]): That

[use case]

Builds a new collection by applying a function to all elements of this 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 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 collection resulting from applying the given collection-valued function f to each element of this collection and concatenating the results.
  • Implicit information
    • This member is added by an implicit conversion from ZippedTraversable2 [El1, El2] to Traversable [(El1, El2)] performed by method zippedTraversable2ToTraversable in scala.runtime.ZippedTraversable2.
  • Definition Classes
    • TraversableLike → GenTraversableLike → FilterMonadic

(added by implicit convertion: scala.runtime.ZippedTraversable2.zippedTraversable2ToTraversable)

def flatten[B](implicit asTraversable: ((El1, El2)) ⇒ GenTraversableOnce[B]): collection.Traversable[B]

[use case]

Converts this collection of traversable collections into a collection formed by the elements of these traversable 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(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 collection resulting from concatenating all element collections.
  • Implicit information
    • This member is added by an implicit conversion from ZippedTraversable2 [El1, El2] to Traversable [(El1, El2)] performed by method zippedTraversable2ToTraversable in scala.runtime.ZippedTraversable2.
  • Definition Classes
    • GenericTraversableTemplate

(added by implicit convertion: scala.runtime.ZippedTraversable2.zippedTraversable2ToTraversable)

def foldLeft[B](z: B)(op: (B, (El1, El2)) ⇒ B): B

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

Note: will not terminate for infinite-sized collections.

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

  • B
    • the result type of the binary operator.
  • z
    • the start value.
  • op
    • the binary operator.
  • returns
    • the result of inserting op between consecutive elements of this collection, going left to right with the start value z on the left:
    op(...op(z, x_1), x_2, ..., x_n)
    
where `x1, ..., xn` are the elements of this collection. Returns `z` if this
collection is empty.
  • Implicit information
    • This member is added by an implicit conversion from ZippedTraversable2 [El1, El2] to Traversable [(El1, El2)] performed by method zippedTraversable2ToTraversable in scala.runtime.ZippedTraversable2.
  • Definition Classes
    • TraversableOnce → GenTraversableOnce

(added by implicit convertion: scala.runtime.ZippedTraversable2.zippedTraversable2ToTraversable)

def foldRight[B](z: B)(op: ((El1, El2), B) ⇒ B): B

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

Note: will not terminate for infinite-sized collections.

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

  • B
    • the result type of the binary operator.
  • z
    • the start value.
  • op
    • the binary operator.
  • returns
    • the result of inserting op between consecutive elements of this collection, going right to left with the start value z on the right:
    op(x_1, op(x_2, ... op(x_n, z)...))
    
where `x1, ..., xn` are the elements of this collection. Returns `z` if this
collection is empty.
  • Implicit information
    • This member is added by an implicit conversion from ZippedTraversable2 [El1, El2] to Traversable [(El1, El2)] performed by method zippedTraversable2ToTraversable in scala.runtime.ZippedTraversable2.
  • Definition Classes
    • TraversableOnce → GenTraversableOnce

(added by implicit convertion: scala.runtime.ZippedTraversable2.zippedTraversable2ToTraversable)

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

Folds the elements of this collection using the specified associative binary operator.

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

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 collection is empty.
  • Implicit information
    • This member is added by an implicit conversion from ZippedTraversable2 [El1, El2] to Traversable [(El1, El2)] performed by method zippedTraversable2ToTraversable in scala.runtime.ZippedTraversable2.
  • Definition Classes
    • TraversableOnce → GenTraversableOnce

(added by implicit convertion: scala.runtime.ZippedTraversable2.zippedTraversable2ToTraversable)

def forall(p: ((El1, El2)) ⇒ Boolean): Boolean

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

Note: may not terminate for infinite-sized collections.

  • p
    • the predicate used to test elements.
  • returns
    • true if this collection is empty or the given predicate p holds for all elements of this collection, otherwise false .
  • Implicit information
    • This member is added by an implicit conversion from ZippedTraversable2 [El1, El2] to Traversable [(El1, El2)] performed by method zippedTraversable2ToTraversable in scala.runtime.ZippedTraversable2.
  • Definition Classes
    • TraversableLike → TraversableOnce → GenTraversableOnce

(added by implicit convertion: scala.runtime.ZippedTraversable2.zippedTraversable2ToTraversable)

def genericBuilder[B]: Builder[B, collection.Traversable[B]]

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

  • Implicit information
    • This member is added by an implicit conversion from ZippedTraversable2 [El1, El2] to Traversable [(El1, El2)] performed by method zippedTraversable2ToTraversable in scala.runtime.ZippedTraversable2.
  • Definition Classes
    • GenericTraversableTemplate

(added by implicit convertion: scala.runtime.ZippedTraversable2.zippedTraversable2ToTraversable)

def groupBy[K](f: ((El1, El2)) ⇒ K): Map[K, collection.Traversable[(El1, El2)]]

Partitions this collection into a map of 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 collection.

  • K
    • the type of keys returned by the discriminator function.
  • f
    • the discriminator function.
  • returns
    • A map from keys to 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 collection of those elements `x` for
which `f(x)` equals `k` .
  • Implicit information
    • This member is added by an implicit conversion from ZippedTraversable2 [El1, El2] to Traversable [(El1, El2)] performed by method zippedTraversable2ToTraversable in scala.runtime.ZippedTraversable2.
  • Definition Classes
    • TraversableLike → GenTraversableLike

(added by implicit convertion: scala.runtime.ZippedTraversable2.zippedTraversable2ToTraversable)

def head: (El1, El2)

Selects the first element of this collection.

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

  • returns
    • the first element of this collection.
  • Implicit information
    • This member is added by an implicit conversion from ZippedTraversable2 [El1, El2] to Traversable [(El1, El2)] performed by method zippedTraversable2ToTraversable in scala.runtime.ZippedTraversable2.
  • Definition Classes
    • TraversableLike → GenTraversableLike
  • Exceptions thrown
    • NoSuchElementException if the collection is empty.

(added by implicit convertion: scala.runtime.ZippedTraversable2.zippedTraversable2ToTraversable)

def headOption: Option[(El1, El2)]

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 collection if it is nonempty, None if it is empty.
  • Implicit information
    • This member is added by an implicit conversion from ZippedTraversable2 [El1, El2] to Traversable [(El1, El2)] performed by method zippedTraversable2ToTraversable in scala.runtime.ZippedTraversable2.
  • Definition Classes
    • TraversableLike → GenTraversableLike

(added by implicit convertion: scala.runtime.ZippedTraversable2.zippedTraversable2ToTraversable)

def init: collection.Traversable[(El1, El2)]

Selects all elements except the last.

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

  • returns
    • a collection consisting of all elements of this collection except the last one.
  • Implicit information
    • This member is added by an implicit conversion from ZippedTraversable2 [El1, El2] to Traversable [(El1, El2)] performed by method zippedTraversable2ToTraversable in scala.runtime.ZippedTraversable2.
  • Definition Classes
    • TraversableLike → GenTraversableLike
  • Exceptions thrown
    • UnsupportedOperationException if the collection is empty.

(added by implicit convertion: scala.runtime.ZippedTraversable2.zippedTraversable2ToTraversable)

def inits: collection.Iterator[collection.Traversable[(El1, El2)]]

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

  • returns
    • an iterator over all the inits of this collection
  • Implicit information
    • This member is added by an implicit conversion from ZippedTraversable2 [El1, El2] to Traversable [(El1, El2)] performed by method zippedTraversable2ToTraversable in scala.runtime.ZippedTraversable2.
  • Definition Classes
    • TraversableLike

Example:

List(1,2,3).inits = Iterator(List(1,2,3), List(1,2), List(1), Nil)

(added by implicit convertion: scala.runtime.ZippedTraversable2.zippedTraversable2ToTraversable)

def last: (El1, El2)

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 collection.
  • Implicit information
    • This member is added by an implicit conversion from ZippedTraversable2 [El1, El2] to Traversable [(El1, El2)] performed by method zippedTraversable2ToTraversable in scala.runtime.ZippedTraversable2.
  • Definition Classes
    • TraversableLike → GenTraversableLike
  • Exceptions thrown
    • NoSuchElementException If the collection is empty.

(added by implicit convertion: scala.runtime.ZippedTraversable2.zippedTraversable2ToTraversable)

def lastOption: Option[(El1, El2)]

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 collection$ if it is nonempty, None if it is empty.
  • Implicit information
    • This member is added by an implicit conversion from ZippedTraversable2 [El1, El2] to Traversable [(El1, El2)] performed by method zippedTraversable2ToTraversable in scala.runtime.ZippedTraversable2.
  • Definition Classes
    • TraversableLike → GenTraversableLike

(added by implicit convertion: scala.runtime.ZippedTraversable2.zippedTraversable2ToTraversable)

def map[B, That](f: ((El1, El2)) ⇒ B)(implicit bf: CanBuildFrom[collection.Traversable[(El1, El2)], B, That]): That

[use case]

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

  • B
    • the element type of the returned collection.
  • f
    • the function to apply to each element.
  • returns
    • a new collection resulting from applying the given function f to each element of this collection and collecting the results.
  • Implicit information
    • This member is added by an implicit conversion from ZippedTraversable2 [El1, El2] to Traversable [(El1, El2)] performed by method zippedTraversable2ToTraversable in scala.runtime.ZippedTraversable2.
  • Definition Classes
    • TraversableLike → GenTraversableLike → FilterMonadic

(added by implicit convertion: scala.runtime.ZippedTraversable2.zippedTraversable2ToTraversable)

def maxBy[B](f: ((El1, El2)) ⇒ B)(implicit cmp: Ordering[B]): (El1, El2)

[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 collection with the largest value measured by function f.
  • Implicit information
    • This member is added by an implicit conversion from ZippedTraversable2 [El1, El2] to Traversable [(El1, El2)] performed by method zippedTraversable2ToTraversable in scala.runtime.ZippedTraversable2.
  • Definition Classes
    • TraversableOnce → GenTraversableOnce

(added by implicit convertion: scala.runtime.ZippedTraversable2.zippedTraversable2ToTraversable)

def minBy[B](f: ((El1, El2)) ⇒ B)(implicit cmp: Ordering[B]): (El1, El2)

[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 collection with the smallest value measured by function f.
  • Implicit information
    • This member is added by an implicit conversion from ZippedTraversable2 [El1, El2] to Traversable [(El1, El2)] performed by method zippedTraversable2ToTraversable in scala.runtime.ZippedTraversable2.
  • Definition Classes
    • TraversableOnce → GenTraversableOnce

(added by implicit convertion: scala.runtime.ZippedTraversable2.zippedTraversable2ToTraversable)

def mkString(sep: String): String

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

  • sep
    • the separator string.
  • returns
    • a string representation of this collection. In the resulting string the string representations (w.r.t. the method toString ) of all elements of this collection are separated by the string sep .
  • Implicit information
    • This member is added by an implicit conversion from ZippedTraversable2 [El1, El2] to Traversable [(El1, El2)] performed by method zippedTraversable2ToTraversable in scala.runtime.ZippedTraversable2.
  • Definition Classes
    • TraversableOnce → GenTraversableOnce

Example:

List(1, 2, 3).mkString("|") = "1|2|3"

(added by implicit convertion: scala.runtime.ZippedTraversable2.zippedTraversable2ToTraversable)

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

Displays all elements of this 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 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 collection are separated by the string sep .
  • Implicit information
    • This member is added by an implicit conversion from ZippedTraversable2 [El1, El2] to Traversable [(El1, El2)] performed by method zippedTraversable2ToTraversable in scala.runtime.ZippedTraversable2.
  • Definition Classes
    • TraversableOnce → GenTraversableOnce

Example:

List(1, 2, 3).mkString("(", "; ", ")") = "(1; 2; 3)"

(added by implicit convertion: scala.runtime.ZippedTraversable2.zippedTraversable2ToTraversable)

def par: ParIterable[(El1, El2)]

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
  • Implicit information
    • This member is added by an implicit conversion from ZippedTraversable2 [El1, El2] to Traversable [(El1, El2)] performed by method zippedTraversable2ToTraversable in scala.runtime.ZippedTraversable2.
  • Definition Classes
    • Parallelizable

(added by implicit convertion: scala.runtime.ZippedTraversable2.zippedTraversable2ToTraversable)

def partition(p: ((El1, El2)) ⇒ Boolean): (collection.Traversable[(El1, El2)], collection.Traversable[(El1, El2)])

Partitions this collection in two collections according to a predicate.

  • p
    • the predicate on which to partition.
  • returns
    • a pair of collections: the first collection consists of all elements that satisfy the predicate p and the second collection consists of all elements that don’t. The relative order of the elements in the resulting collections is the same as in the original collection.
  • Implicit information
    • This member is added by an implicit conversion from ZippedTraversable2 [El1, El2] to Traversable [(El1, El2)] performed by method zippedTraversable2ToTraversable in scala.runtime.ZippedTraversable2.
  • Definition Classes
    • TraversableLike → GenTraversableLike

(added by implicit convertion: scala.runtime.ZippedTraversable2.zippedTraversable2ToTraversable)

def reduceLeftOption[B >: A](op: (B, (El1, El2)) ⇒ B): Option[B]

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

Note: will not terminate for infinite-sized collections.

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

  • B
    • the result type of the binary operator.
  • op
    • the binary operator.
  • returns
    • an option value containing the result of reduceLeft(op) if this collection is nonempty, None otherwise.
  • Implicit information
    • This member is added by an implicit conversion from ZippedTraversable2 [El1, El2] to Traversable [(El1, El2)] performed by method zippedTraversable2ToTraversable in scala.runtime.ZippedTraversable2.
  • Definition Classes
    • TraversableOnce → GenTraversableOnce

(added by implicit convertion: scala.runtime.ZippedTraversable2.zippedTraversable2ToTraversable)

def reduceLeft[B >: A](op: (B, (El1, El2)) ⇒ B): B

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

Note: will not terminate for infinite-sized collections.

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

  • B
    • the result type of the binary operator.
  • op
    • the binary operator.
  • returns
    • the result of inserting op between consecutive elements of this collection, going left to right:
    op( op( ... op(x_1, x_2) ..., x_{n-1}), x_n)
    
where `x1, ..., xn` are the elements of this collection.
  • Implicit information
    • This member is added by an implicit conversion from ZippedTraversable2 [El1, El2] to Traversable [(El1, El2)] performed by method zippedTraversable2ToTraversable in scala.runtime.ZippedTraversable2.
  • Definition Classes
    • TraversableOnce
  • Exceptions thrown
    • UnsupportedOperationException if this collection is empty.

(added by implicit convertion: scala.runtime.ZippedTraversable2.zippedTraversable2ToTraversable)

def reduceOption[A1 >: A](op: (A1, A1) ⇒ A1): Option[A1]

Reduces the elements of this collection, if any, using the specified associative binary operator.

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

  • 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.
  • Implicit information
    • This member is added by an implicit conversion from ZippedTraversable2 [El1, El2] to Traversable [(El1, El2)] performed by method zippedTraversable2ToTraversable in scala.runtime.ZippedTraversable2.
  • Definition Classes
    • TraversableOnce → GenTraversableOnce

(added by implicit convertion: scala.runtime.ZippedTraversable2.zippedTraversable2ToTraversable)

def reduceRightOption[B >: A](op: ((El1, El2), B) ⇒ B): Option[B]

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

Note: will not terminate for infinite-sized collections.

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

  • B
    • the result type of the binary operator.
  • op
    • the binary operator.
  • returns
    • an option value containing the result of reduceRight(op) if this collection is nonempty, None otherwise.
  • Implicit information
    • This member is added by an implicit conversion from ZippedTraversable2 [El1, El2] to Traversable [(El1, El2)] performed by method zippedTraversable2ToTraversable in scala.runtime.ZippedTraversable2.
  • Definition Classes
    • TraversableOnce → GenTraversableOnce

(added by implicit convertion: scala.runtime.ZippedTraversable2.zippedTraversable2ToTraversable)

def reduceRight[B >: A](op: ((El1, El2), B) ⇒ B): B

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

Note: will not terminate for infinite-sized collections.

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

  • B
    • the result type of the binary operator.
  • op
    • the binary operator.
  • returns
    • the result of inserting op between consecutive elements of this collection, going right to left:
    op(x_1, op(x_2, ..., op(x_{n-1}, x_n)...))
    
where `x1, ..., xn` are the elements of this collection.
  • Implicit information
    • This member is added by an implicit conversion from ZippedTraversable2 [El1, El2] to Traversable [(El1, El2)] performed by method zippedTraversable2ToTraversable in scala.runtime.ZippedTraversable2.
  • Definition Classes
    • TraversableOnce → GenTraversableOnce
  • Exceptions thrown
    • UnsupportedOperationException if this collection is empty.

(added by implicit convertion: scala.runtime.ZippedTraversable2.zippedTraversable2ToTraversable)

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

Reduces the elements of this collection using the specified associative binary operator.

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

  • 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 collection is nonempty.
  • Implicit information
    • This member is added by an implicit conversion from ZippedTraversable2 [El1, El2] to Traversable [(El1, El2)] performed by method zippedTraversable2ToTraversable in scala.runtime.ZippedTraversable2.
  • Definition Classes
    • TraversableOnce → GenTraversableOnce
  • Exceptions thrown
    • UnsupportedOperationException if this collection is empty.

(added by implicit convertion: scala.runtime.ZippedTraversable2.zippedTraversable2ToTraversable)

def repr: collection.Traversable[(El1, El2)]

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

  • Implicit information
    • This member is added by an implicit conversion from ZippedTraversable2 [El1, El2] to Traversable [(El1, El2)] performed by method zippedTraversable2ToTraversable in scala.runtime.ZippedTraversable2.
  • Definition Classes
    • TraversableLike → GenTraversableLike

(added by implicit convertion: scala.runtime.ZippedTraversable2.zippedTraversable2ToTraversable)

def scanLeft[B, That](z: B)(op: (B, (El1, El2)) ⇒ B)(implicit bf: CanBuildFrom[collection.Traversable[(El1, El2)], B, That]): That

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
  • Implicit information
    • This member is added by an implicit conversion from ZippedTraversable2 [El1, El2] to Traversable [(El1, El2)] performed by method zippedTraversable2ToTraversable in scala.runtime.ZippedTraversable2.
  • Definition Classes
    • TraversableLike → GenTraversableLike

(added by implicit convertion: scala.runtime.ZippedTraversable2.zippedTraversable2ToTraversable)

def scanRight[B, That](z: B)(op: ((El1, El2), B) ⇒ B)(implicit bf: CanBuildFrom[collection.Traversable[(El1, El2)], B, That]): That

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
  • Implicit information
    • This member is added by an implicit conversion from ZippedTraversable2 [El1, El2] to Traversable [(El1, El2)] performed by method zippedTraversable2ToTraversable in scala.runtime.ZippedTraversable2.
  • Definition Classes
    • TraversableLike → GenTraversableLike
  • Annotations
    • @migration
  • Migration
    • (Changed in version 2.9.0) The behavior of scanRight has changed. The previous behavior can be reproduced with scanRight.reverse.

(added by implicit convertion: scala.runtime.ZippedTraversable2.zippedTraversable2ToTraversable)

def scan[B >: A, That](z: B)(op: (B, B) ⇒ B)(implicit cbf: CanBuildFrom[collection.Traversable[(El1, El2)], B, That]): That

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 collection containing the prefix scan of the elements in this collection
  • Implicit information
    • This member is added by an implicit conversion from ZippedTraversable2 [El1, El2] to Traversable [(El1, El2)] performed by method zippedTraversable2ToTraversable in scala.runtime.ZippedTraversable2.
  • Definition Classes
    • TraversableLike → GenTraversableLike

(added by implicit convertion: scala.runtime.ZippedTraversable2.zippedTraversable2ToTraversable)

def seq: collection.Traversable[(El1, El2)]

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.
  • Implicit information
    • This member is added by an implicit conversion from ZippedTraversable2 [El1, El2] to Traversable [(El1, El2)] performed by method zippedTraversable2ToTraversable in scala.runtime.ZippedTraversable2.
  • Definition Classes
    • Traversable → GenTraversable → Parallelizable → TraversableOnce → GenTraversableOnce

(added by implicit convertion: scala.runtime.ZippedTraversable2.zippedTraversable2ToTraversable)

def slice(from: Int, until: Int): collection.Traversable[(El1, El2)]

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 collection containing the elements greater than or equal to index from extending up to (but not including) index until of this collection.
  • Implicit information
    • This member is added by an implicit conversion from ZippedTraversable2 [El1, El2] to Traversable [(El1, El2)] performed by method zippedTraversable2ToTraversable in scala.runtime.ZippedTraversable2.
  • Definition Classes
    • TraversableLike → GenTraversableLike

(added by implicit convertion: scala.runtime.ZippedTraversable2.zippedTraversable2ToTraversable)

def span(p: ((El1, El2)) ⇒ Boolean): (collection.Traversable[(El1, El2)], collection.Traversable[(El1, El2)])

Splits this 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 collection whose elements all satisfy p , and the rest of this collection.
  • Implicit information
    • This member is added by an implicit conversion from ZippedTraversable2 [El1, El2] to Traversable [(El1, El2)] performed by method zippedTraversable2ToTraversable in scala.runtime.ZippedTraversable2.
  • Definition Classes
    • TraversableLike → GenTraversableLike

(added by implicit convertion: scala.runtime.ZippedTraversable2.zippedTraversable2ToTraversable)

def splitAt(n: Int): (collection.Traversable[(El1, El2)], collection.Traversable[(El1, El2)])

Splits this 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 collections consisting of the first n elements of this collection, and the other elements.
  • Implicit information
    • This member is added by an implicit conversion from ZippedTraversable2 [El1, El2] to Traversable [(El1, El2)] performed by method zippedTraversable2ToTraversable in scala.runtime.ZippedTraversable2.
  • Definition Classes
    • TraversableLike → GenTraversableLike

(added by implicit convertion: scala.runtime.ZippedTraversable2.zippedTraversable2ToTraversable)

def tail: collection.Traversable[(El1, El2)]

Selects all elements except the first.

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

  • returns
    • a collection consisting of all elements of this collection except the first one.
  • Implicit information
    • This member is added by an implicit conversion from ZippedTraversable2 [El1, El2] to Traversable [(El1, El2)] performed by method zippedTraversable2ToTraversable in scala.runtime.ZippedTraversable2.
  • Definition Classes
    • TraversableLike → GenTraversableLike
  • Exceptions thrown
    • UnsupportedOperationException if the collection is empty.

(added by implicit convertion: scala.runtime.ZippedTraversable2.zippedTraversable2ToTraversable)

def tails: collection.Iterator[collection.Traversable[(El1, El2)]]

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

  • returns
    • an iterator over all the tails of this collection
  • Implicit information
    • This member is added by an implicit conversion from ZippedTraversable2 [El1, El2] to Traversable [(El1, El2)] performed by method zippedTraversable2ToTraversable in scala.runtime.ZippedTraversable2.
  • Definition Classes
    • TraversableLike

Example:

List(1,2,3).tails = Iterator(List(1,2,3), List(2,3), List(3), Nil)

(added by implicit convertion: scala.runtime.ZippedTraversable2.zippedTraversable2ToTraversable)

def take(n: Int): collection.Traversable[(El1, El2)]

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 collection.
  • returns
    • a collection consisting only of the first n elements of this collection, or else the whole collection, if it has less than n elements.
  • Implicit information
    • This member is added by an implicit conversion from ZippedTraversable2 [El1, El2] to Traversable [(El1, El2)] performed by method zippedTraversable2ToTraversable in scala.runtime.ZippedTraversable2.
  • Definition Classes
    • TraversableLike → GenTraversableLike

(added by implicit convertion: scala.runtime.ZippedTraversable2.zippedTraversable2ToTraversable)

def takeWhile(p: ((El1, El2)) ⇒ Boolean): collection.Traversable[(El1, El2)]

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 collection whose elements all satisfy the predicate p .
  • Implicit information
    • This member is added by an implicit conversion from ZippedTraversable2 [El1, El2] to Traversable [(El1, El2)] performed by method zippedTraversable2ToTraversable in scala.runtime.ZippedTraversable2.
  • Definition Classes
    • TraversableLike → GenTraversableLike

(added by implicit convertion: scala.runtime.ZippedTraversable2.zippedTraversable2ToTraversable)

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

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

Note: will not terminate for infinite-sized collections.

  • returns
    • a buffer containing all elements of this collection.
  • Implicit information
    • This member is added by an implicit conversion from ZippedTraversable2 [El1, El2] to Traversable [(El1, El2)] performed by method zippedTraversable2ToTraversable in scala.runtime.ZippedTraversable2.
  • Definition Classes
    • TraversableOnce → GenTraversableOnce

(added by implicit convertion: scala.runtime.ZippedTraversable2.zippedTraversable2ToTraversable)

def toIndexedSeq: collection.immutable.IndexedSeq[(El1, El2)]

Converts this collection to an indexed sequence.

Note: will not terminate for infinite-sized collections.

  • returns
    • an indexed sequence containing all elements of this collection.
  • Implicit information
    • This member is added by an implicit conversion from ZippedTraversable2 [El1, El2] to Traversable [(El1, El2)] performed by method zippedTraversable2ToTraversable in scala.runtime.ZippedTraversable2.
  • Definition Classes
    • TraversableOnce → GenTraversableOnce

(added by implicit convertion: scala.runtime.ZippedTraversable2.zippedTraversable2ToTraversable)

def toIterable: collection.Iterable[(El1, El2)]

Converts this 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 collection.
  • Implicit information
    • This member is added by an implicit conversion from ZippedTraversable2 [El1, El2] to Traversable [(El1, El2)] performed by method zippedTraversable2ToTraversable in scala.runtime.ZippedTraversable2.
  • Definition Classes
    • TraversableOnce → GenTraversableOnce

(added by implicit convertion: scala.runtime.ZippedTraversable2.zippedTraversable2ToTraversable)

def toIterator: collection.Iterator[(El1, El2)]

Returns an Iterator over the elements in this 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 collection.
  • Implicit information
    • This member is added by an implicit conversion from ZippedTraversable2 [El1, El2] to Traversable [(El1, El2)] performed by method zippedTraversable2ToTraversable in scala.runtime.ZippedTraversable2.
  • Definition Classes
    • TraversableLike → GenTraversableOnce

(added by implicit convertion: scala.runtime.ZippedTraversable2.zippedTraversable2ToTraversable)

def toList: List[(El1, El2)]

Converts this collection to a list.

Note: will not terminate for infinite-sized collections.

  • returns
    • a list containing all elements of this collection.
  • Implicit information
    • This member is added by an implicit conversion from ZippedTraversable2 [El1, El2] to Traversable [(El1, El2)] performed by method zippedTraversable2ToTraversable in scala.runtime.ZippedTraversable2.
  • Definition Classes
    • TraversableOnce → GenTraversableOnce

(added by implicit convertion: scala.runtime.ZippedTraversable2.zippedTraversable2ToTraversable)

def toMap[T, U](implicit ev: <:<[(El1, El2), (T, U)]): Map[T, U]

[use case]

Converts this 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.

  • returns
    • a map of type immutable.Map[T, U] containing all key/value pairs of type (T, U) of this collection.
  • Implicit information
    • This member is added by an implicit conversion from ZippedTraversable2 [El1, El2] to Traversable [(El1, El2)] performed by method zippedTraversable2ToTraversable in scala.runtime.ZippedTraversable2.
  • Definition Classes
    • TraversableOnce → GenTraversableOnce

(added by implicit convertion: scala.runtime.ZippedTraversable2.zippedTraversable2ToTraversable)

def toSeq: collection.Seq[(El1, El2)]

Converts this 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 collection.
  • Implicit information
    • This member is added by an implicit conversion from ZippedTraversable2 [El1, El2] to Traversable [(El1, El2)] performed by method zippedTraversable2ToTraversable in scala.runtime.ZippedTraversable2.
  • Definition Classes
    • TraversableOnce → GenTraversableOnce

(added by implicit convertion: scala.runtime.ZippedTraversable2.zippedTraversable2ToTraversable)

def toSet[B >: A]: Set[B]

Converts this collection to a set.

Note: will not terminate for infinite-sized collections.

  • returns
    • a set containing all elements of this collection.
  • Implicit information
    • This member is added by an implicit conversion from ZippedTraversable2 [El1, El2] to Traversable [(El1, El2)] performed by method zippedTraversable2ToTraversable in scala.runtime.ZippedTraversable2.
  • Definition Classes
    • TraversableOnce → GenTraversableOnce

(added by implicit convertion: scala.runtime.ZippedTraversable2.zippedTraversable2ToTraversable)

def toStream: Stream[(El1, El2)]

Converts this collection to a stream.

  • returns
    • a stream containing all elements of this collection.
  • Implicit information
    • This member is added by an implicit conversion from ZippedTraversable2 [El1, El2] to Traversable [(El1, El2)] performed by method zippedTraversable2ToTraversable in scala.runtime.ZippedTraversable2.
  • Definition Classes
    • TraversableLike → GenTraversableOnce

(added by implicit convertion: scala.runtime.ZippedTraversable2.zippedTraversable2ToTraversable)

def toTraversable: collection.Traversable[(El1, El2)]

Converts this 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 collection.
  • Implicit information
    • This member is added by an implicit conversion from ZippedTraversable2 [El1, El2] to Traversable [(El1, El2)] performed by method zippedTraversable2ToTraversable in scala.runtime.ZippedTraversable2.
  • Definition Classes
    • TraversableLike → TraversableOnce → GenTraversableOnce
  • Annotations
    • @ deprecatedOverriding (message =…, since = “2.11.0”)

(added by implicit convertion: scala.runtime.ZippedTraversable2.zippedTraversable2ToTraversable)

def toVector: Vector[(El1, El2)]

Converts this collection to a Vector.

Note: will not terminate for infinite-sized collections.

  • returns
    • a vector containing all elements of this collection.
  • Implicit information
    • This member is added by an implicit conversion from ZippedTraversable2 [El1, El2] to Traversable [(El1, El2)] performed by method zippedTraversable2ToTraversable in scala.runtime.ZippedTraversable2.
  • Definition Classes
    • TraversableOnce → GenTraversableOnce

(added by implicit convertion: scala.runtime.ZippedTraversable2.zippedTraversable2ToTraversable)

def transpose[B](implicit asTraversable: ((El1, El2)) ⇒ GenTraversableOnce[B]): collection.Traversable[collection.Traversable[B]]

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 n th row the n th column of this collection.
  • Implicit information
    • This member is added by an implicit conversion from ZippedTraversable2 [El1, El2] to Traversable [(El1, El2)] performed by method zippedTraversable2ToTraversable in scala.runtime.ZippedTraversable2.
  • 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.

(added by implicit convertion: scala.runtime.ZippedTraversable2.zippedTraversable2ToTraversable)

def unzip3[A1, A2, A3](implicit asTriple: ((El1, El2)) ⇒ (A1, A2, A3)): (collection.Traversable[A1], collection.Traversable[A2], collection.Traversable[A3])

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

val xs = Traversable(
           (1, "one", '1'),
           (2, "two", '2'),
           (3, "three", '3')).unzip3
// xs == (Traversable(1, 2, 3),
//        Traversable(one, two, three),
//        Traversable(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.
  • Implicit information
    • This member is added by an implicit conversion from ZippedTraversable2 [El1, El2] to Traversable [(El1, El2)] performed by method zippedTraversable2ToTraversable in scala.runtime.ZippedTraversable2.
  • Definition Classes
    • GenericTraversableTemplate

(added by implicit convertion: scala.runtime.ZippedTraversable2.zippedTraversable2ToTraversable)

def unzip[A1, A2](implicit asPair: ((El1, El2)) ⇒ (A1, A2)): (collection.Traversable[A1], collection.Traversable[A2])

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

val xs = Traversable(
           (1, "one"),
           (2, "two"),
           (3, "three")).unzip
// xs == (Traversable(1, 2, 3),
//        Traversable(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.
  • Implicit information
    • This member is added by an implicit conversion from ZippedTraversable2 [El1, El2] to Traversable [(El1, El2)] performed by method zippedTraversable2ToTraversable in scala.runtime.ZippedTraversable2.
  • Definition Classes
    • GenericTraversableTemplate

(added by implicit convertion: scala.runtime.ZippedTraversable2.zippedTraversable2ToTraversable)

def view(from: Int, until: Int): TraversableView[(El1, El2), collection.Traversable[(El1, El2)]]

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

Note: the difference between view and slice is that view produces a view of the current collection, whereas slice produces a new 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 collection, starting at index from and extending up to (but not including) index until .
  • Implicit information
    • This member is added by an implicit conversion from ZippedTraversable2 [El1, El2] to Traversable [(El1, El2)] performed by method zippedTraversable2ToTraversable in scala.runtime.ZippedTraversable2.
  • Definition Classes
    • TraversableLike

(added by implicit convertion: scala.runtime.ZippedTraversable2.zippedTraversable2ToTraversable)

def view: TraversableView[(El1, El2), collection.Traversable[(El1, El2)]]

Creates a non-strict view of this collection.

  • returns
    • a non-strict view of this collection.
  • Implicit information
    • This member is added by an implicit conversion from ZippedTraversable2 [El1, El2] to Traversable [(El1, El2)] performed by method zippedTraversable2ToTraversable in scala.runtime.ZippedTraversable2.
  • Definition Classes
    • TraversableLike

(added by implicit convertion: scala.runtime.ZippedTraversable2.zippedTraversable2ToTraversable)

def withFilter(p: ((El1, El2)) ⇒ Boolean): FilterMonadic[(El1, El2), collection.Traversable[(El1, El2)]]

Creates a non-strict filter of this 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 collection which satisfy the predicate p .
  • Implicit information
    • This member is added by an implicit conversion from ZippedTraversable2 [El1, El2] to Traversable [(El1, El2)] performed by method zippedTraversable2ToTraversable in scala.runtime.ZippedTraversable2.
  • Definition Classes
    • TraversableLike → FilterMonadic (added by implicit convertion: scala.runtime.ZippedTraversable2.zippedTraversable2ToTraversable)

Full Source:

/*                     __                                               *\
**     ________ ___   / /  ___     Scala API                            **
**    / __/ __// _ | / /  / _ |    (c) 2002-2013, LAMP/EPFL             **
**  __\ \/ /__/ __ |/ /__/ __ |    http://scala-lang.org/               **
** /____/\___/_/ |_/____/_/ | |                                         **
**                          |/                                          **
\*                                                                      */

package scala
package runtime


import scala.collection.{ TraversableLike, IterableLike }
import scala.collection.generic.{ CanBuildFrom => CBF }
import scala.language.{ higherKinds, implicitConversions }

/** This interface is intended as a minimal interface, not complicated
 *  by the requirement to resolve type constructors, for implicit search (which only
 *  needs to find an implicit conversion to Traversable for our purposes.)
 *  @define Coll `ZippedTraversable2`
 *  @define coll collection
 *  @define collectExample
 *  @define willNotTerminateInf
 */
trait ZippedTraversable2[+El1, +El2] extends Any {
  def foreach[U](f: (El1, El2) => U): Unit
}
object ZippedTraversable2 {
  implicit def zippedTraversable2ToTraversable[El1, El2](zz: ZippedTraversable2[El1, El2]): Traversable[(El1, El2)] = {
    new scala.collection.AbstractTraversable[(El1, El2)] {
      def foreach[U](f: ((El1, El2)) => U): Unit = zz foreach Function.untupled(f)
    }
  }
}

final class Tuple2Zipped[El1, Repr1, El2, Repr2](val colls: (TraversableLike[El1, Repr1], IterableLike[El2, Repr2])) extends AnyVal with ZippedTraversable2[El1, El2] {
  // This would be better as "private def coll1 = colls._1" but
  // SI-6215 precludes private methods in value classes.
  def map[B, To](f: (El1, El2) => B)(implicit cbf: CBF[Repr1, B, To]): To = {
    val b = cbf(colls._1.repr)
    b.sizeHint(colls._1)
    val elems2 = colls._2.iterator

    for (el1 <- colls._1) {
      if (elems2.hasNext)
        b += f(el1, elems2.next())
      else
        return b.result()
    }

    b.result()
  }

  def flatMap[B, To](f: (El1, El2) => TraversableOnce[B])(implicit cbf: CBF[Repr1, B, To]): To = {
    val b = cbf(colls._1.repr)
    val elems2 = colls._2.iterator

    for (el1 <- colls._1) {
      if (elems2.hasNext)
        b ++= f(el1, elems2.next())
      else
        return b.result()
    }

    b.result()
  }

  def filter[To1, To2](f: (El1, El2) => Boolean)(implicit cbf1: CBF[Repr1, El1, To1], cbf2: CBF[Repr2, El2, To2]): (To1, To2) = {
    val b1 = cbf1(colls._1.repr)
    val b2 = cbf2(colls._2.repr)
    val elems2 = colls._2.iterator

    for (el1 <- colls._1) {
      if (elems2.hasNext) {
        val el2 = elems2.next()
        if (f(el1, el2)) {
          b1 += el1
          b2 += el2
        }
      }
      else return (b1.result(), b2.result())
    }

    (b1.result(), b2.result())
  }

  def exists(@deprecatedName('f) p: (El1, El2) => Boolean): Boolean = {
    val elems2 = colls._2.iterator

    for (el1 <- colls._1) {
      if (elems2.hasNext) {
        if (p(el1, elems2.next()))
          return true
      }
      else return false
    }
    false
  }

  def forall(@deprecatedName('f) p: (El1, El2) => Boolean): Boolean =
    !exists((x, y) => !p(x, y))

  def foreach[U](f: (El1, El2) => U): Unit = {
    val elems2 = colls._2.iterator

    for (el1 <- colls._1) {
      if (elems2.hasNext)
        f(el1, elems2.next())
      else
        return
    }
  }

  override def toString = "(%s, %s).zipped".format(colls._1.toString, colls._2.toString)
}

object Tuple2Zipped {
  final class Ops[T1, T2](val x: (T1, T2)) extends AnyVal {
    def invert[El1, CC1[X] <: TraversableOnce[X], El2, CC2[X] <: TraversableOnce[X], That]
      (implicit w1: T1 <:< CC1[El1],
                w2: T2 <:< CC2[El2],
                bf: scala.collection.generic.CanBuildFrom[CC1[_], (El1, El2), That]
      ): That = {
        val buf = bf(x._1)
        val it1 = x._1.toIterator
        val it2 = x._2.toIterator
        while (it1.hasNext && it2.hasNext)
          buf += ((it1.next(), it2.next()))

        buf.result()
      }

    def zipped[El1, Repr1, El2, Repr2]
      (implicit w1: T1 => TraversableLike[El1, Repr1],
                w2: T2 => IterableLike[El2, Repr2]
      ): Tuple2Zipped[El1, Repr1, El2, Repr2] = new Tuple2Zipped((x._1, x._2))
  }
}