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/*
* Scala (https://www.scala-lang.org)
*
* Copyright EPFL and Lightbend, Inc.
*
* Licensed under Apache License 2.0
* (http://www.apache.org/licenses/LICENSE-2.0).
*
* See the NOTICE file distributed with this work for
* additional information regarding copyright ownership.
*/
package scala.collection
import scala.annotation.{implicitNotFound, nowarn}
import scala.annotation.unchecked.uncheckedVariance
/** Base type of sorted sets */
trait SortedSet[A] extends Set[A]
with SortedSetOps[A, SortedSet, SortedSet[A]]
with SortedSetFactoryDefaults[A, SortedSet, Set] {
def unsorted: Set[A] = this
def sortedIterableFactory: SortedIterableFactory[SortedSet] = SortedSet
@nowarn("""cat=deprecation&origin=scala\.collection\.Iterable\.stringPrefix""")
override protected[this] def stringPrefix: String = "SortedSet"
override def equals(that: Any): Boolean = that match {
case _ if this eq that.asInstanceOf[AnyRef] => true
case ss: SortedSet[A @unchecked] if ss.ordering == this.ordering =>
(ss canEqual this) &&
(this.size == ss.size) && {
val i1 = this.iterator
val i2 = ss.iterator
var allEqual = true
while (allEqual && i1.hasNext)
allEqual = ordering.equiv(i1.next(), i2.next())
allEqual
}
case _ =>
super.equals(that)
}
}
trait SortedSetOps[A, +CC[X] <: SortedSet[X], +C <: SortedSetOps[A, CC, C]]
extends SetOps[A, Set, C]
with SortedOps[A, C] {
/** The companion object of this sorted set, providing various factory methods.
*
* @note When implementing a custom collection type and refining `CC` to the new type, this
* method needs to be overridden to return a factory for the new type (the compiler will
* issue an error otherwise).
*/
def sortedIterableFactory: SortedIterableFactory[CC]
def unsorted: Set[A]
/**
* Creates an iterator that contains all values from this collection
* greater than or equal to `start` according to the ordering of
* this collection. x.iteratorFrom(y) is equivalent to but will usually
* be more efficient than x.from(y).iterator
*
* @param start The lower-bound (inclusive) of the iterator
*/
def iteratorFrom(start: A): Iterator[A]
@deprecated("Use `iteratorFrom` instead.", "2.13.0")
@`inline` def keysIteratorFrom(start: A): Iterator[A] = iteratorFrom(start)
def firstKey: A = head
def lastKey: A = last
/** Find the smallest element larger than or equal to a given key.
* @param key The given key.
* @return `None` if there is no such node.
*/
def minAfter(key: A): Option[A] = rangeFrom(key).headOption
/** Find the largest element less than a given key.
* @param key The given key.
* @return `None` if there is no such node.
*/
def maxBefore(key: A): Option[A] = rangeUntil(key).lastOption
override def min[B >: A](implicit ord: Ordering[B]): A =
if (isEmpty) throw new UnsupportedOperationException("empty.min")
else if (ord == ordering) head
else if (ord isReverseOf ordering) last
else super.min[B] // need the type annotation for it to infer the correct implicit
override def max[B >: A](implicit ord: Ordering[B]): A =
if (isEmpty) throw new UnsupportedOperationException("empty.max")
else if (ord == ordering) last
else if (ord isReverseOf ordering) head
else super.max[B] // need the type annotation for it to infer the correct implicit
def rangeTo(to: A): C = {
val i = rangeFrom(to).iterator
if (i.isEmpty) return coll
val next = i.next()
if (ordering.compare(next, to) == 0)
if (i.isEmpty) coll
else rangeUntil(i.next())
else
rangeUntil(next)
}
/** Builds a new sorted collection by applying a function to all elements of this $coll.
*
* @param f the function to apply to each element.
* @tparam B the element type of the returned collection.
* @return a new $coll resulting from applying the given function
* `f` to each element of this $coll and collecting the results.
*/
def map[B](f: A => B)(implicit @implicitNotFound(SortedSetOps.ordMsg) ev: Ordering[B]): CC[B] =
sortedIterableFactory.from(new View.Map(this, f))
/** Builds a new sorted collection by applying a function to all elements of this $coll
* and using the elements of the resulting collections.
*
* @param f the function to apply to each element.
* @tparam B the element type of the returned collection.
* @return a new $coll resulting from applying the given collection-valued function
* `f` to each element of this $coll and concatenating the results.
*/
def flatMap[B](f: A => IterableOnce[B])(implicit @implicitNotFound(SortedSetOps.ordMsg) ev: Ordering[B]): CC[B] =
sortedIterableFactory.from(new View.FlatMap(this, f))
/** Returns a $coll formed from this $coll 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.
*
* @param that The iterable providing the second half of each result pair
* @tparam B the type of the second half of the returned pairs
* @return a new $coll containing pairs consisting of corresponding elements of this $coll and `that`.
* The length of the returned collection is the minimum of the lengths of this $coll and `that`.
*/
def zip[B](that: IterableOnce[B])(implicit @implicitNotFound(SortedSetOps.zipOrdMsg) ev: Ordering[(A @uncheckedVariance, B)]): CC[(A @uncheckedVariance, B)] = // sound bcs of VarianceNote
sortedIterableFactory.from(that match {
case that: Iterable[B] => new View.Zip(this, that)
case _ => iterator.zip(that)
})
/** Builds a new sorted collection by applying a partial function to all elements of this $coll
* on which the function is defined.
*
* @param pf the partial function which filters and maps the $coll.
* @tparam B the element type of the returned collection.
* @return a new $coll resulting from applying the given partial function
* `pf` to each element on which it is defined and collecting the results.
* The order of the elements is preserved.
*/
def collect[B](pf: scala.PartialFunction[A, B])(implicit @implicitNotFound(SortedSetOps.ordMsg) ev: Ordering[B]): CC[B] =
sortedIterableFactory.from(new View.Collect(this, pf))
}
object SortedSetOps {
private[collection] final val ordMsg = "No implicit Ordering[${B}] found to build a SortedSet[${B}]. You may want to upcast to a Set[${A}] first by calling `unsorted`."
private[collection] final val zipOrdMsg = "No implicit Ordering[${B}] found to build a SortedSet[(${A}, ${B})]. You may want to upcast to a Set[${A}] first by calling `unsorted`."
/** Specialize `WithFilter` for sorted collections
*
* @define coll sorted collection
*/
class WithFilter[+A, +IterableCC[_], +CC[X] <: SortedSet[X]](
self: SortedSetOps[A, CC, _] with IterableOps[A, IterableCC, _],
p: A => Boolean
) extends IterableOps.WithFilter[A, IterableCC](self, p) {
def map[B : Ordering](f: A => B): CC[B] =
self.sortedIterableFactory.from(new View.Map(filtered, f))
def flatMap[B : Ordering](f: A => IterableOnce[B]): CC[B] =
self.sortedIterableFactory.from(new View.FlatMap(filtered, f))
override def withFilter(q: A => Boolean): WithFilter[A, IterableCC, CC] =
new WithFilter[A, IterableCC, CC](self, (a: A) => p(a) && q(a))
}
}
@SerialVersionUID(3L)
object SortedSet extends SortedIterableFactory.Delegate[SortedSet](immutable.SortedSet)