Class PriorityQueue.PriorityQueue

sealed class PriorityQueue[A](implicit val ord: Ordering[A]) extends AbstractIterable[A] with Iterable[A] with IterableOps[A, Iterable, PriorityQueue[A]] with StrictOptimizedIterableOps[A, Iterable, PriorityQueue[A]] with Builder[A, PriorityQueue[A]] with Cloneable[PriorityQueue[A]] with Growable[A] with Serializable

This class implements priority queues using a heap. To prioritize elements of type A there must be an implicit Ordering[A] available at creation.

If multiple elements have the same priority in the ordering of this PriorityQueue, no guarantees are made regarding the order in which elements are returned by dequeue or dequeueAll. In particular, that means this class does not guarantee first in first out behaviour that may be incorrectly inferred from the Queue part of the name of this class.

Only the dequeue and dequeueAll methods will return elements in priority order (while removing elements from the heap). Standard collection methods including drop, iterator, and toString will remove or traverse the heap in whichever order seems most convenient.

Therefore, printing a PriorityQueue will not reveal the priority order of the elements, though the highest-priority element will be printed first. To print the elements in order, one must duplicate the PriorityQueue (by using clone, for instance) and then dequeue them:

val pq = collection.mutable.PriorityQueue(1, 2, 5, 3, 7)
println(pq)                  // elements probably not in order
println(pq.clone.dequeueAll) // prints ArraySeq(7, 5, 3, 2, 1)

Concrete methods

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def ++(xs: IterableOnce[A]): PriorityQueue[A]

Adds all elements provided by a IterableOnce object into the priority queue.

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override def addAll(xs: IterableOnce[A]): PriorityQueue.this.type

Adds all elements produced by an IterableOnce to this priority queue.

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def addOne(elem: A): PriorityQueue.this.type

Inserts a single element into the priority queue.

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def clear(): Unit

Removes all elements from the queue. After this operation is completed, the queue will be empty.

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override def clone(): PriorityQueue[A]

This method clones the priority queue.

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

Copy elements to an array, returning the number of elements written.

Fills the given array xs starting at index start with at most len elements of this priority queue.

Copying will stop once either all the elements of this priority queue have been copied, or the end of the array is reached, or len elements have been copied.

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def dequeue(): A

Returns the element with the highest priority in the queue, and removes this element from the queue.

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def dequeueAll[A1 >: A]: Seq[A1]

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override def empty: PriorityQueue[A]

The empty iterable of the same type as this iterable

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def enqueue(elems: A*): Unit

Adds all elements to the queue.

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override def head: A

Returns the element with the highest priority in the queue, or throws an error if there is no element contained in the queue.

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override def isEmpty: Boolean

Tests whether the priority queue is empty.

Note: Implementations in subclasses that are not repeatedly traversable must take care not to consume any elements when isEmpty is called.

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override def iterator: Iterator[A]

Returns an iterator which yields all the elements.

Note: The order of elements returned is undefined. If you want to traverse the elements in priority queue order, use clone().dequeueAll.iterator.

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override def knownSize: Int

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def length: Int

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def mapInPlace(f: A => A): PriorityQueue.this.type

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def result(): PriorityQueue[A]

Result collection consisting of all elements appended so far.

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def reverse: PriorityQueue[A]

Returns the reverse of this priority queue. The new priority queue has the same elements as the original, but the opposite ordering.

For example, the element with the highest priority in pq has the lowest priority in pq.reverse, and vice versa.

Ties are handled arbitrarily. Elements with equal priority may or may not be reversed with respect to each other.

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def reverseIterator: Iterator[A]

Returns an iterator which yields all the elements in the reverse order than that returned by the method iterator.

Note: The order of elements returned is undefined.

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override def size: Int

The size of this priority queue.

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override def toList: List[A]

Converts this priority queue to a list.

Note: the order of elements is undefined.

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def toQueue: Queue[A]

Returns a regular queue containing the same elements.

Note: the order of elements is undefined.

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override def toString(): String

Returns a textual representation of a queue as a string.

Inherited methods

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final def ++[B >: A](suffix: IterableOnce[B]): CC[B]

Alias for concat

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final def ++=(xs: IterableOnce[A]): Growable.this.type

Alias for addAll

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final def +=(elem: A): Growable.this.type

Alias for addOne

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final 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

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final 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

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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)

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override def collect[B](pf: PartialFunction[A, B]): CC[B]

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

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

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def concat[B >: A](suffix: IterableOnce[B]): CC[B]

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

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

Copy elements to an array, returning the number of elements written.

Fills the given array xs starting at index start with values of this collection.

Copying will stop once either all the elements of this collection have been copied, or the end of the array is reached.

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

Copy elements to an array, returning the number of elements written.

Fills the given array xs starting at index start with values of this collection.

Copying will stop once either all the elements of this collection have been copied, or the end of the array is reached.

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def corresponds[B](that: IterableOnce[B])(p: (A, B) => Boolean): Boolean

Tests whether every element of this collection's iterator relates to the corresponding element of another collection by satisfying a test predicate.

Note: will not terminate for infinite-sized collections.

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def count(p: A => Boolean): Int

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

Note: will not terminate for infinite-sized collections.

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def drop(n: Int): C

Selects all elements except first n ones.

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

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override def dropRight(n: Int): C

The rest of the collection without its n last elements. For linear, immutable collections this should avoid making a copy.

Note: Even when applied to a view or a lazy collection it will always force the elements.

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def dropWhile(p: A => Boolean): C

Drops longest prefix of elements that satisfy a predicate.

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

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def exists(p: A => Boolean): Boolean

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

Note: may not terminate for infinite-sized collections.

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override def filter(pred: A => Boolean): C

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

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override def filterNot(pred: A => Boolean): C

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

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def find(p: A => Boolean): Option[A]

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.

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override def flatMap[B](f: A => IterableOnce[B]): CC[B]

Builds a new iterable collection by applying a function to all elements of this iterable 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 iterable 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: String) => word.toSeq)

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

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

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override def flatten[B](implicit toIterableOnce: A => IterableOnce[B]): CC[B]

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

The resulting collection's type will be guided by the type of iterable 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)

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

Folds the elements of this collection using the specified associative binary operator. The default implementation in IterableOnce is equivalent to foldLeft but may be overridden for more efficient traversal orders.

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

Note: will not terminate for infinite-sized collections.

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def foldLeft[B](z: B)(op: (B, A) => 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.

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def foldRight[B](z: B)(op: (A, 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.

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def forall(p: A => Boolean): Boolean

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

Note: may not terminate for infinite-sized collections.

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def foreach[U](f: A => U): Unit

Apply f to each element for its side effects Note: [U] parameter needed to help scalac's type inference.

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def groupBy[K](f: A => K): Map[K, C]

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

Note: Even when applied to a view or a lazy collection it will always force the elements.

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

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def groupMap[K, B](key: A => K)(f: A => B): Map[K, CC[B]]

Partitions this iterable collection into a map of iterable collections according to a discriminator function key. Each element in a group is transformed into a value of type B using the value function.

It is equivalent to groupBy(key).mapValues(_.map(f)), but more efficient.

case class User(name: String, age: Int)

def namesByAge(users: Seq[User]): Map[Int, Seq[String]] =
  users.groupMap(_.age)(_.name)

Note: Even when applied to a view or a lazy collection it will always force the elements.

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def groupMapReduce[K, B](key: A => K)(f: A => B)(reduce: (B, B) => B): Map[K, B]

Partitions this iterable collection into a map according to a discriminator function key. All the values that have the same discriminator are then transformed by the f function and then reduced into a single value with the reduce function.

It is equivalent to groupBy(key).mapValues(_.map(f).reduce(reduce)), but more efficient.

def occurrences[A](as: Seq[A]): Map[A, Int] =
  as.groupMapReduce(identity)(_ => 1)(_ + _)

Note: Even when applied to a view or a lazy collection it will always force the elements.

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def grouped(size: Int): Iterator[C]

Partitions elements in fixed size iterable collections.

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def headOption: Option[A]

Optionally selects the first element.

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

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def init: C

The initial part of the collection without its last element.

Note: Even when applied to a view or a lazy collection it will always force the elements.

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def inits: Iterator[C]

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

Note: Even when applied to a view or a lazy collection it will always force the elements.

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override def isTraversableAgain: Boolean

Tests whether this iterable collection can be repeatedly traversed. Always true for Iterables and false for Iterators unless overridden.

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override def iterableFactory: IterableFactory[Iterable]

The companion object of this iterable collection, providing various factory methods.

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def last: A

Selects the last element.

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

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def lastOption: Option[A]

Optionally selects the last element.

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

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def lazyZip[B](that: Iterable[B]): LazyZip2[A, B, Iterable]

Analogous to zip except that the elements in each collection are not consumed until a strict operation is invoked on the returned LazyZip2 decorator.

Calls to lazyZip can be chained to support higher arities (up to 4) without incurring the expense of constructing and deconstructing intermediary tuples.

val xs = List(1, 2, 3)
val res = (xs lazyZip xs lazyZip xs lazyZip xs).map((a, b, c, d) => a + b + c + d)
// res == List(4, 8, 12)

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override def map[B](f: A => B): CC[B]

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

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def mapResult[NewTo](f: PriorityQueue[A] => NewTo): Builder[A, NewTo]

A builder resulting from this builder my mapping the result using f.

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

Finds the largest element.

Note: will not terminate for infinite-sized collections.

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

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

Note: will not terminate for infinite-sized collections.

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def maxByOption[B](f: A => B)(implicit cmp: Ordering[B]): Option[A]

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

Note: will not terminate for infinite-sized collections.

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def maxOption[B >: A](implicit ord: Ordering[B]): Option[A]

Finds the largest element.

Note: will not terminate for infinite-sized collections.

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

Finds the smallest element.

Note: will not terminate for infinite-sized collections.

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

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

Note: will not terminate for infinite-sized collections.

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def minByOption[B](f: A => B)(implicit cmp: Ordering[B]): Option[A]

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

Note: will not terminate for infinite-sized collections.

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def minOption[B >: A](implicit ord: Ordering[B]): Option[A]

Finds the smallest element.

Note: will not terminate for infinite-sized collections.

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final def mkString: String

Displays all elements of this collection in a string.

Delegates to addString, which can be overridden.

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final def mkString(sep: String): String

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

Delegates to addString, which can be overridden.

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

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

Delegates to addString, which can be overridden.

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def nonEmpty: Boolean

Tests whether the collection is not empty.

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override def partition(p: A => Boolean): (C, C)

A pair of, first, all elements that satisfy predicate p and, second, all elements that do not. Interesting because it splits a collection in two.

The default implementation provided here needs to traverse the collection twice. Strict collections have an overridden version of partition in StrictOptimizedIterableOps, which requires only a single traversal.

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override def partitionMap[A1, A2](f: A => Either[A1, A2]): (CC[A1], CC[A2])

Applies a function f to each element of the iterable collection and returns a pair of iterable collections: the first one made of those values returned by f that were wrapped in scala.util.Left, and the second one made of those wrapped in scala.util.Right.

Example:

val xs = Iterable(1, "one", 2, "two", 3, "three") partitionMap {
 case i: Int => Left(i)
 case s: String => Right(s)
}
// xs == (Iterable(1, 2, 3),
//        Iterable(one, two, three))

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

Multiplies up the elements of this collection.

Note: will not terminate for infinite-sized collections.

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def reduce[B >: A](op: (B, B) => B): B

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.

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

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def reduceLeftOption[B >: A](op: (B, A) => 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.

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def reduceOption[B >: A](op: (B, B) => B): Option[B]

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.

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def reduceRight[B >: A](op: (A, 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.

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def reduceRightOption[B >: A](op: (A, 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.

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protected def reversed: Iterable[A]

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def scan[B >: A](z: B)(op: (B, B) => B): CC[B]

Computes a prefix scan of the elements of the collection.

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

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override def scanLeft[B](z: B)(op: (B, A) => B): CC[B]

Produces a iterable collection containing cumulative results of applying the operator going left to right, including the initial value.

Note: will not terminate for infinite-sized collections.

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

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def scanRight[B](z: B)(op: (A, B) => B): CC[B]

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.

Note: Even when applied to a view or a lazy collection it will always force the elements.

Example:

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

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def sizeCompare(that: Iterable[_]): Int

Compares the size of this iterable collection to the size of another Iterable.

x <  0       if this.size <  that.size
x == 0       if this.size == that.size
x >  0       if this.size >  that.size

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def sizeCompare(otherSize: Int): Int

Compares the size of this iterable collection to a test value.

x <  0       if this.size <  otherSize
x == 0       if this.size == otherSize
x >  0       if this.size >  otherSize

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final def sizeHint(coll: IterableOnce[_], delta: Int): Unit

Gives a hint that one expects the result of this builder to have the same size as the given collection, plus some delta. This will provide a hint only if the collection has a known size Some builder classes will optimize their representation based on the hint. However, builder implementations are still required to work correctly even if the hint is wrong, i.e. a different number of elements is added.

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def sizeHint(size: Int): Unit

Gives a hint how many elements are expected to be added when the next result is called. Some builder classes will optimize their representation based on the hint. However, builder implementations are still required to work correctly even if the hint is wrong, i.e. a different number of elements is added.

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final def sizeHintBounded(size: Int, boundingColl: Iterable[_]): Unit

Gives a hint how many elements are expected to be added when the next result is called, together with an upper bound given by the size of some other collection. Some builder classes will optimize their representation based on the hint. However, builder implementations are still required to work correctly even if the hint is wrong, i.e. a different number of elements is added.

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final def sizeIs: SizeCompareOps

Returns a value class containing operations for comparing the size of this iterable collection to a test value.

These operations are implemented in terms of sizeCompare(Int), and allow the following more readable usages:

this.sizeIs < size     // this.sizeCompare(size) < 0
this.sizeIs <= size    // this.sizeCompare(size) <= 0
this.sizeIs == size    // this.sizeCompare(size) == 0
this.sizeIs != size    // this.sizeCompare(size) != 0
this.sizeIs >= size    // this.sizeCompare(size) >= 0
this.sizeIs > size     // this.sizeCompare(size) > 0

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def slice(from: Int, until: Int): C

Selects an interval of elements. The returned iterable 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.

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def sliding(size: Int, step: Int): Iterator[C]

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

The returned iterator will be empty when called on an empty collection. The last element the iterator produces may be smaller than the window size when the original collection isn't exhausted by the window before it and its last element isn't skipped by the step before it.

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def sliding(size: Int): Iterator[C]

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

An empty collection returns an empty iterator, and a non-empty collection containing fewer elements than the window size returns an iterator that will produce the original collection as its only element.

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override def span(p: A => Boolean): (C, C)

Splits this iterable 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.

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override def splitAt(n: Int): (C, C)

Splits this iterable collection into a prefix/suffix pair at a given position.

Note: c splitAt n is equivalent to (but possibly more efficient than) (c take n, c drop n).

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

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def stepper[S <: Stepper[_]](implicit shape: StepperShape[A, S]): S

Returns a scala.collection.Stepper for the elements of this collection.

The Stepper enables creating a Java stream to operate on the collection, see scala.jdk.StreamConverters. For collections holding primitive values, the Stepper can be used as an iterator which doesn't box the elements.

The implicit scala.collection.StepperShape parameter defines the resulting Stepper type according to the element type of this collection.

• For collections of Int, Short, Byte or Char, an scala.collection.IntStepper is returned

• For collections of Double or Float, a scala.collection.DoubleStepper is returned

• For collections of Long a scala.collection.LongStepper is returned

• For any other element type, an scala.collection.AnyStepper is returned

Note that this method is overridden in subclasses and the return type is refined to S with EfficientSplit, for example scala.collection.IndexedSeqOps.stepper. For Steppers marked with scala.collection.Stepper.EfficientSplit, the converters in scala.jdk.StreamConverters allow creating parallel streams, whereas bare Steppers can be converted only to sequential streams.

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

Sums up the elements of this collection.

Note: will not terminate for infinite-sized collections.

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def tail: C

The rest of the collection without its first element.

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def tails: Iterator[C]

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

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def take(n: Int): C

Selects the first n elements.

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

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override def takeRight(n: Int): C

A collection containing the last n elements of this collection.

Note: Even when applied to a view or a lazy collection it will always force the elements.

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def takeWhile(p: A => Boolean): C

Takes longest prefix of elements that satisfy a predicate.

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

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override def tapEach[U](f: A => U): C

Applies a side-effecting function to each element in this collection. Strict collections will apply f to their elements immediately, while lazy collections like Views and LazyLists will only apply f on each element if and when that element is evaluated, and each time that element is evaluated.

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def to[C1](factory: Factory[A, C1]): C1

Given a collection factory factory, convert this collection to the appropriate representation for the current element type A. Example uses:

xs.to(List) xs.to(ArrayBuffer) xs.to(BitSet) // for xs: Iterable[Int]

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def toArray[B >: A : ClassTag]: Array[B]

Convert collection to array.

Implementation note: DO NOT call Array.from from this method.

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

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def toIndexedSeq: IndexedSeq[A]

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def toMap[K, V](implicit ev: A <:< (K, V)): Map[K, V]

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def toSeq: Seq[A]

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

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def toVector: Vector[A]

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def transpose[B](implicit asIterable: A => Iterable[B]): CC[CC[B]]

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

The resulting collection's type will be guided by the static type of iterable 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))

Note: Even when applied to a view or a lazy collection it will always force the elements.

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override def unzip[A1, A2](implicit asPair: A => (A1, A2)): (CC[A1], CC[A2])

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

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

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override def unzip3[A1, A2, A3](implicit asTriple: A => (A1, A2, A3)): (CC[A1], CC[A2], CC[A3])

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

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

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def view: View[A]

A view over the elements of this collection.

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def withFilter(p: A => Boolean): WithFilter[A, CC]

Creates a non-strict filter of this iterable 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.

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override def zip[B](that: IterableOnce[B]): CC[(A, B)]

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

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def zipAll[A1 >: A, B](that: Iterable[B], thisElem: A1, thatElem: B): CC[(A1, B)]

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

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override def zipWithIndex: CC[(A, Int)]

Zips this iterable collection with its indices.

Implicits

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implicit val ord: Ordering[A]