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author | James Iry <jamesiry@gmail.com> | 2013-02-20 09:06:03 -0800 |
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committer | James Iry <jamesiry@gmail.com> | 2013-02-20 09:06:03 -0800 |
commit | 70956e560a11996e1d801d59b312dfe9d56b7a74 (patch) | |
tree | 6b923275bf605be045b83d15ef3da45c151e4a30 /src | |
parent | bafebe1c161f8db0be758c30fe5cc51082a56427 (diff) | |
parent | 07ba1f8002b5f81bd3849ba38144efdabc8ef4a4 (diff) | |
download | scala-70956e560a11996e1d801d59b312dfe9d56b7a74.tar.gz scala-70956e560a11996e1d801d59b312dfe9d56b7a74.tar.bz2 scala-70956e560a11996e1d801d59b312dfe9d56b7a74.zip |
Merge pull request #2119 from JamesIry/master_SI-6642
SI-6642 Adds iteratorFrom, keysIteratorFrom, and valuesIteratorFrom
Diffstat (limited to 'src')
-rw-r--r-- | src/library/scala/Enumeration.scala | 3 | ||||
-rw-r--r-- | src/library/scala/collection/BitSetLike.scala | 6 | ||||
-rw-r--r-- | src/library/scala/collection/SortedMapLike.scala | 29 | ||||
-rw-r--r-- | src/library/scala/collection/SortedSetLike.scala | 10 | ||||
-rw-r--r-- | src/library/scala/collection/generic/Sorted.scala | 12 | ||||
-rw-r--r-- | src/library/scala/collection/immutable/RedBlackTree.scala | 102 | ||||
-rw-r--r-- | src/library/scala/collection/immutable/SortedMap.scala | 6 | ||||
-rw-r--r-- | src/library/scala/collection/immutable/TreeMap.scala | 4 | ||||
-rw-r--r-- | src/library/scala/collection/immutable/TreeSet.scala | 1 | ||||
-rw-r--r-- | src/library/scala/collection/mutable/AVLTree.scala | 11 | ||||
-rw-r--r-- | src/library/scala/collection/mutable/TreeSet.scala | 110 |
11 files changed, 197 insertions, 97 deletions
diff --git a/src/library/scala/Enumeration.scala b/src/library/scala/Enumeration.scala index 21f0c8fd3e..d522539e83 100644 --- a/src/library/scala/Enumeration.scala +++ b/src/library/scala/Enumeration.scala @@ -254,7 +254,8 @@ abstract class Enumeration (initial: Int) extends Serializable { def contains(v: Value) = nnIds contains (v.id - bottomId) def + (value: Value) = new ValueSet(nnIds + (value.id - bottomId)) def - (value: Value) = new ValueSet(nnIds - (value.id - bottomId)) - def iterator = nnIds.iterator map (id => thisenum.apply(id + bottomId)) + def iterator = nnIds.iterator map (id => thisenum.apply(bottomId + id)) + override def keysIteratorFrom(start: Value) = nnIds keysIteratorFrom start.id map (id => thisenum.apply(bottomId + id)) override def stringPrefix = thisenum + ".ValueSet" /** Creates a bit mask for the zero-adjusted ids in this set as a * new array of longs */ diff --git a/src/library/scala/collection/BitSetLike.scala b/src/library/scala/collection/BitSetLike.scala index d0f4e323c7..bf05331cb1 100644 --- a/src/library/scala/collection/BitSetLike.scala +++ b/src/library/scala/collection/BitSetLike.scala @@ -98,8 +98,10 @@ trait BitSetLike[+This <: BitSetLike[This] with SortedSet[Int]] extends SortedSe fromBitMaskNoCopy(a) } - def iterator: Iterator[Int] = new AbstractIterator[Int] { - private var current = 0 + def iterator: Iterator[Int] = iteratorFrom(0) + + override def keysIteratorFrom(start: Int) = new AbstractIterator[Int] { + private var current = start private val end = nwords * WordLength def hasNext: Boolean = { while (current < end && !self.contains(current)) current += 1 diff --git a/src/library/scala/collection/SortedMapLike.scala b/src/library/scala/collection/SortedMapLike.scala index 57ad3497c7..3c3e6095df 100644 --- a/src/library/scala/collection/SortedMapLike.scala +++ b/src/library/scala/collection/SortedMapLike.scala @@ -42,6 +42,7 @@ self => val map = self.rangeImpl(from, until) new map.DefaultKeySortedSet } + override def keysIteratorFrom(start: A) = self.keysIteratorFrom(start) } /** Add a key/value pair to this map. @@ -76,11 +77,17 @@ self => override def filterKeys(p: A => Boolean): SortedMap[A, B] = new FilteredKeys(p) with SortedMap.Default[A, B] { implicit def ordering: Ordering[A] = self.ordering override def rangeImpl(from : Option[A], until : Option[A]): SortedMap[A, B] = self.rangeImpl(from, until).filterKeys(p) + override def iteratorFrom(start: A) = self iteratorFrom start filter {case (k, _) => p(k)} + override def keysIteratorFrom(start: A) = self keysIteratorFrom start filter p + override def valuesIteratorFrom(start: A) = self iteratorFrom start collect {case (k,v) if p(k) => v} } override def mapValues[C](f: B => C): SortedMap[A, C] = new MappedValues(f) with SortedMap.Default[A, C] { implicit def ordering: Ordering[A] = self.ordering override def rangeImpl(from : Option[A], until : Option[A]): SortedMap[A, C] = self.rangeImpl(from, until).mapValues(f) + override def iteratorFrom(start: A) = (self iteratorFrom start) map {case (k,v) => (k, f(v))} + override def keysIteratorFrom(start: A) = self keysIteratorFrom start + override def valuesIteratorFrom(start: A) = self valuesIteratorFrom start map f } /** Adds a number of elements provided by a traversable object @@ -91,6 +98,28 @@ self => override def ++[B1 >: B](xs: GenTraversableOnce[(A, B1)]): SortedMap[A, B1] = ((repr: SortedMap[A, B1]) /: xs.seq) (_ + _) + /** + * Creates an iterator over all the key/value pairs + * contained in this map having a key greater than or + * equal to `start` according to the ordering of + * this map. x.iteratorFrom(y) is equivalent + * to but often more efficient than x.from(y).iterator. + * + * @param start The lower bound (inclusive) + * on the keys to be returned + */ + def iteratorFrom(start: A): Iterator[(A, B)] + /** + * Creates an iterator over all the values contained in this + * map that are associated with a key greater than or equal to `start` + * according to the ordering of this map. x.valuesIteratorFrom(y) is + * equivalent to but often more efficient than + * x.from(y).valuesIterator. + * + * @param start The lower bound (inclusive) + * on the keys to be returned + */ + def valuesIteratorFrom(start: A): Iterator[B] } diff --git a/src/library/scala/collection/SortedSetLike.scala b/src/library/scala/collection/SortedSetLike.scala index 71b45c72ff..6d1d1ac111 100644 --- a/src/library/scala/collection/SortedSetLike.scala +++ b/src/library/scala/collection/SortedSetLike.scala @@ -40,4 +40,14 @@ self => case that: SortedSet[_] if that.ordering == ordering => that.hasAll(this.iterator) case that => super.subsetOf(that) } + + /** + * 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] = keysIteratorFrom(start) } diff --git a/src/library/scala/collection/generic/Sorted.scala b/src/library/scala/collection/generic/Sorted.scala index f962b26bd3..b3847fffc9 100644 --- a/src/library/scala/collection/generic/Sorted.scala +++ b/src/library/scala/collection/generic/Sorted.scala @@ -78,6 +78,18 @@ trait Sorted[K, +This <: Sorted[K, This]] { else until(next) } + + /** + * Creates an iterator over all the keys(or elements) contained in this + * collection greater than or equal to `start` + * according to the ordering of this collection. x.keysIteratorFrom(y) + * is equivalent to but often more efficient than + * x.from(y).keysIterator. + * + * @param start The lower bound (inclusive) + * on the keys to be returned + */ + def keysIteratorFrom(start: K): Iterator[K] protected def hasAll(j: Iterator[K]): Boolean = { val i = keySet.iterator diff --git a/src/library/scala/collection/immutable/RedBlackTree.scala b/src/library/scala/collection/immutable/RedBlackTree.scala index 99f8d95517..1cd0128c05 100644 --- a/src/library/scala/collection/immutable/RedBlackTree.scala +++ b/src/library/scala/collection/immutable/RedBlackTree.scala @@ -24,13 +24,13 @@ import scala.annotation.meta.getter * * @since 2.10 */ -private[immutable] +private[collection] object RedBlackTree { def isEmpty(tree: Tree[_, _]): Boolean = tree eq null - def contains[A](tree: Tree[A, _], x: A)(implicit ordering: Ordering[A]): Boolean = lookup(tree, x) ne null - def get[A, B](tree: Tree[A, B], x: A)(implicit ordering: Ordering[A]): Option[B] = lookup(tree, x) match { + def contains[A: Ordering](tree: Tree[A, _], x: A): Boolean = lookup(tree, x) ne null + def get[A: Ordering, B](tree: Tree[A, B], x: A): Option[B] = lookup(tree, x) match { case null => None case tree => Some(tree.value) } @@ -44,8 +44,27 @@ object RedBlackTree { } def count(tree: Tree[_, _]) = if (tree eq null) 0 else tree.count - def update[A, B, B1 >: B](tree: Tree[A, B], k: A, v: B1, overwrite: Boolean)(implicit ordering: Ordering[A]): Tree[A, B1] = blacken(upd(tree, k, v, overwrite)) - def delete[A, B](tree: Tree[A, B], k: A)(implicit ordering: Ordering[A]): Tree[A, B] = blacken(del(tree, k)) + /** + * Count all the nodes with keys greater than or equal to the lower bound and less than the upper bound. + * The two bounds are optional. + */ + def countInRange[A](tree: Tree[A, _], from: Option[A], to:Option[A])(implicit ordering: Ordering[A]) : Int = + if (tree eq null) 0 else + (from, to) match { + // with no bounds use this node's count + case (None, None) => tree.count + // if node is less than the lower bound, try the tree on the right, it might be in range + case (Some(lb), _) if ordering.lt(tree.key, lb) => countInRange(tree.right, from, to) + // if node is greater than or equal to the upper bound, try the tree on the left, it might be in range + case (_, Some(ub)) if ordering.gteq(tree.key, ub) => countInRange(tree.left, from, to) + // node is in range so the tree on the left will all be less than the upper bound and the tree on the + // right will all be greater than or equal to the lower bound. So 1 for this node plus + // count the subtrees by stripping off the bounds that we don't need any more + case _ => 1 + countInRange(tree.left, from, None) + countInRange(tree.right, None, to) + + } + def update[A: Ordering, B, B1 >: B](tree: Tree[A, B], k: A, v: B1, overwrite: Boolean): Tree[A, B1] = blacken(upd(tree, k, v, overwrite)) + def delete[A: Ordering, B](tree: Tree[A, B], k: A): Tree[A, B] = blacken(del(tree, k)) def rangeImpl[A: Ordering, B](tree: Tree[A, B], from: Option[A], until: Option[A]): Tree[A, B] = (from, until) match { case (Some(from), Some(until)) => this.range(tree, from, until) case (Some(from), None) => this.from(tree, from) @@ -91,9 +110,9 @@ object RedBlackTree { if (tree.right ne null) _foreachKey(tree.right, f) } - def iterator[A, B](tree: Tree[A, B]): Iterator[(A, B)] = new EntriesIterator(tree) - def keysIterator[A, _](tree: Tree[A, _]): Iterator[A] = new KeysIterator(tree) - def valuesIterator[_, B](tree: Tree[_, B]): Iterator[B] = new ValuesIterator(tree) + def iterator[A: Ordering, B](tree: Tree[A, B], start: Option[A] = None): Iterator[(A, B)] = new EntriesIterator(tree, start) + def keysIterator[A: Ordering](tree: Tree[A, _], start: Option[A] = None): Iterator[A] = new KeysIterator(tree, start) + def valuesIterator[A: Ordering, B](tree: Tree[A, B], start: Option[A] = None): Iterator[B] = new ValuesIterator(tree, start) @tailrec def nth[A, B](tree: Tree[A, B], n: Int): Tree[A, B] = { @@ -425,32 +444,28 @@ object RedBlackTree { def unapply[A, B](t: BlackTree[A, B]) = Some((t.key, t.value, t.left, t.right)) } - private[this] abstract class TreeIterator[A, B, R](tree: Tree[A, B]) extends Iterator[R] { + private[this] abstract class TreeIterator[A, B, R](root: Tree[A, B], start: Option[A])(implicit ordering: Ordering[A]) extends Iterator[R] { protected[this] def nextResult(tree: Tree[A, B]): R - override def hasNext: Boolean = next ne null + override def hasNext: Boolean = lookahead ne null - override def next: R = next match { + override def next: R = lookahead match { case null => throw new NoSuchElementException("next on empty iterator") case tree => - next = findNext(tree.right) + lookahead = findLeftMostOrPopOnEmpty(goRight(tree)) nextResult(tree) } @tailrec - private[this] def findNext(tree: Tree[A, B]): Tree[A, B] = { - if (tree eq null) popPath() + private[this] def findLeftMostOrPopOnEmpty(tree: Tree[A, B]): Tree[A, B] = + if (tree eq null) popNext() else if (tree.left eq null) tree - else { - pushPath(tree) - findNext(tree.left) - } - } + else findLeftMostOrPopOnEmpty(goLeft(tree)) - private[this] def pushPath(tree: Tree[A, B]) { + private[this] def pushNext(tree: Tree[A, B]) { try { - path(index) = tree + stackOfNexts(index) = tree index += 1 } catch { case _: ArrayIndexOutOfBoundsException => @@ -462,17 +477,17 @@ object RedBlackTree { * An exception handler is used instead of an if-condition to optimize the normal path. * This makes a large difference in iteration speed! */ - assert(index >= path.length) - path :+= null - pushPath(tree) + assert(index >= stackOfNexts.length) + stackOfNexts :+= null + pushNext(tree) } } - private[this] def popPath(): Tree[A, B] = if (index == 0) null else { + private[this] def popNext(): Tree[A, B] = if (index == 0) null else { index -= 1 - path(index) + stackOfNexts(index) } - private[this] var path = if (tree eq null) null else { + private[this] var stackOfNexts = if (root eq null) null else { /* * According to "Ralf Hinze. Constructing red-black trees" [http://www.cs.ox.ac.uk/ralf.hinze/publications/#P5] * the maximum height of a red-black tree is 2*log_2(n + 2) - 2. @@ -481,22 +496,45 @@ object RedBlackTree { * * We also don't store the deepest nodes in the path so the maximum path length is further reduced by one. */ - val maximumHeight = 2 * (32 - Integer.numberOfLeadingZeros(tree.count + 2 - 1)) - 2 - 1 + val maximumHeight = 2 * (32 - Integer.numberOfLeadingZeros(root.count + 2 - 1)) - 2 - 1 new Array[Tree[A, B]](maximumHeight) } private[this] var index = 0 - private[this] var next: Tree[A, B] = findNext(tree) + private[this] var lookahead: Tree[A, B] = start map startFrom getOrElse findLeftMostOrPopOnEmpty(root) + + /** + * Find the leftmost subtree whose key is equal to the given key, or if no such thing, + * the leftmost subtree with the key that would be "next" after it according + * to the ordering. Along the way build up the iterator's path stack so that "next" + * functionality works. + */ + private[this] def startFrom(key: A) : Tree[A,B] = if (root eq null) null else { + @tailrec def find(tree: Tree[A, B]): Tree[A, B] = + if (tree eq null) popNext + else find( + if (ordering.lteq(key, tree.key)) goLeft(tree) + else goRight(tree) + ) + find(root) + } + + private[this] def goLeft(tree: Tree[A, B]) = { + pushNext(tree) + tree.left + } + + private[this] def goRight(tree: Tree[A, B]) = tree.right } - private[this] class EntriesIterator[A, B](tree: Tree[A, B]) extends TreeIterator[A, B, (A, B)](tree) { + private[this] class EntriesIterator[A: Ordering, B](tree: Tree[A, B], focus: Option[A]) extends TreeIterator[A, B, (A, B)](tree, focus) { override def nextResult(tree: Tree[A, B]) = (tree.key, tree.value) } - private[this] class KeysIterator[A, B](tree: Tree[A, B]) extends TreeIterator[A, B, A](tree) { + private[this] class KeysIterator[A: Ordering, B](tree: Tree[A, B], focus: Option[A]) extends TreeIterator[A, B, A](tree, focus) { override def nextResult(tree: Tree[A, B]) = tree.key } - private[this] class ValuesIterator[A, B](tree: Tree[A, B]) extends TreeIterator[A, B, B](tree) { + private[this] class ValuesIterator[A: Ordering, B](tree: Tree[A, B], focus: Option[A]) extends TreeIterator[A, B, B](tree, focus) { override def nextResult(tree: Tree[A, B]) = tree.value } } diff --git a/src/library/scala/collection/immutable/SortedMap.scala b/src/library/scala/collection/immutable/SortedMap.scala index eb04231c55..5e833f87af 100644 --- a/src/library/scala/collection/immutable/SortedMap.scala +++ b/src/library/scala/collection/immutable/SortedMap.scala @@ -82,11 +82,17 @@ self => override def filterKeys(p: A => Boolean): SortedMap[A, B] = new FilteredKeys(p) with SortedMap.Default[A, B] { implicit def ordering: Ordering[A] = self.ordering override def rangeImpl(from : Option[A], until : Option[A]): SortedMap[A, B] = self.rangeImpl(from, until).filterKeys(p) + override def iteratorFrom(start: A) = self iteratorFrom start filter {case (k, _) => p(k)} + override def keysIteratorFrom(start : A) = self keysIteratorFrom start filter p + override def valuesIteratorFrom(start : A) = self iteratorFrom start collect {case (k,v) if p(k) => v} } override def mapValues[C](f: B => C): SortedMap[A, C] = new MappedValues(f) with SortedMap.Default[A, C] { implicit def ordering: Ordering[A] = self.ordering override def rangeImpl(from : Option[A], until : Option[A]): SortedMap[A, C] = self.rangeImpl(from, until).mapValues(f) + override def iteratorFrom(start: A) = self iteratorFrom start map {case (k, v) => (k, f(v))} + override def keysIteratorFrom(start : A) = self keysIteratorFrom start + override def valuesIteratorFrom(start : A) = self valuesIteratorFrom start map f } } diff --git a/src/library/scala/collection/immutable/TreeMap.scala b/src/library/scala/collection/immutable/TreeMap.scala index 9a87d8636b..a6a6b75c32 100644 --- a/src/library/scala/collection/immutable/TreeMap.scala +++ b/src/library/scala/collection/immutable/TreeMap.scala @@ -189,9 +189,13 @@ class TreeMap[A, +B] private (tree: RB.Tree[A, B])(implicit val ordering: Orderi * @return the new iterator */ override def iterator: Iterator[(A, B)] = RB.iterator(tree) + override def iteratorFrom(start: A): Iterator[(A, B)] = RB.iterator(tree, Some(start)) override def keysIterator: Iterator[A] = RB.keysIterator(tree) + override def keysIteratorFrom(start: A): Iterator[A] = RB.keysIterator(tree, Some(start)) + override def valuesIterator: Iterator[B] = RB.valuesIterator(tree) + override def valuesIteratorFrom(start: A): Iterator[B] = RB.valuesIterator(tree, Some(start)) override def contains(key: A): Boolean = RB.contains(tree, key) override def isDefinedAt(key: A): Boolean = RB.contains(tree, key) diff --git a/src/library/scala/collection/immutable/TreeSet.scala b/src/library/scala/collection/immutable/TreeSet.scala index 8bceb936aa..67668b3bef 100644 --- a/src/library/scala/collection/immutable/TreeSet.scala +++ b/src/library/scala/collection/immutable/TreeSet.scala @@ -144,6 +144,7 @@ class TreeSet[A] private (tree: RB.Tree[A, Unit])(implicit val ordering: Orderin * @return the new iterator */ def iterator: Iterator[A] = RB.keysIterator(tree) + override def keysIteratorFrom(start: A): Iterator[A] = RB.keysIterator(tree, Some(start)) override def foreach[U](f: A => U) = RB.foreachKey(tree, f) diff --git a/src/library/scala/collection/mutable/AVLTree.scala b/src/library/scala/collection/mutable/AVLTree.scala index 157e5dae62..da63778fcc 100644 --- a/src/library/scala/collection/mutable/AVLTree.scala +++ b/src/library/scala/collection/mutable/AVLTree.scala @@ -15,7 +15,7 @@ package mutable * An immutable AVL Tree implementation used by mutable.TreeSet * * @author Lucien Pereira - * + * @deprecated("AVLTree and its related classes are being removed from the standard library since they're not different enough from RedBlackTree to justify keeping them.", "2.11") */ private[mutable] sealed trait AVLTree[+A] extends Serializable { def balance: Int @@ -65,12 +65,18 @@ private[mutable] sealed trait AVLTree[+A] extends Serializable { def doubleRightRotation[B >: A]: Node[B] = sys.error("Should not happen.") } +/** + * @deprecated("AVLTree and its related classes are being removed from the standard library since they're not different enough from RedBlackTree to justify keeping them.", "2.11") + */ private case object Leaf extends AVLTree[Nothing] { override val balance: Int = 0 override val depth: Int = -1 } +/** + * @deprecated("AVLTree and its related classes are being removed from the standard library since they're not different enough from RedBlackTree to justify keeping them.", "2.11") + */ private case class Node[A](val data: A, val left: AVLTree[A], val right: AVLTree[A]) extends AVLTree[A] { override val balance: Int = right.depth - left.depth @@ -205,6 +211,9 @@ private case class Node[A](val data: A, val left: AVLTree[A], val right: AVLTree } } +/** + * @deprecated("AVLTree and its related classes are being removed from the standard library since they're not different enough from RedBlackTree to justify keeping them.", "2.11") + */ private class AVLIterator[A](root: Node[A]) extends Iterator[A] { val stack = mutable.ArrayStack[Node[A]](root) diveLeft() diff --git a/src/library/scala/collection/mutable/TreeSet.scala b/src/library/scala/collection/mutable/TreeSet.scala index 5197af1b04..9113d8221b 100644 --- a/src/library/scala/collection/mutable/TreeSet.scala +++ b/src/library/scala/collection/mutable/TreeSet.scala @@ -10,6 +10,8 @@ package scala.collection package mutable import generic._ +import scala.collection.immutable.{RedBlackTree => RB} +import scala.runtime.ObjectRef /** * @define Coll `mutable.TreeSet` @@ -29,95 +31,81 @@ object TreeSet extends MutableSortedSetFactory[TreeSet] { } /** - * A mutable SortedSet using an immutable AVL Tree as underlying data structure. + * A mutable SortedSet using an immutable RedBlack Tree as underlying data structure. * * @author Lucien Pereira * */ -class TreeSet[A](implicit val ordering: Ordering[A]) extends SortedSet[A] with SetLike[A, TreeSet[A]] +class TreeSet[A] private (treeRef: ObjectRef[RB.Tree[A, Null]], from: Option[A], until: Option[A])(implicit val ordering: Ordering[A]) + extends SortedSet[A] with SetLike[A, TreeSet[A]] with SortedSetLike[A, TreeSet[A]] with Set[A] with Serializable { - // Projection constructor - private def this(base: Option[TreeSet[A]], from: Option[A], until: Option[A])(implicit ordering: Ordering[A]) { - this(); - this.base = base - this.from = from - this.until = until - } - - private var base: Option[TreeSet[A]] = None - - private var from: Option[A] = None - - private var until: Option[A] = None - - private var avl: AVLTree[A] = Leaf - - private var cardinality: Int = 0 + def this()(implicit ordering: Ordering[A]) = this(new ObjectRef(null), None, None) - def resolve: TreeSet[A] = base.getOrElse(this) - - private def isLeftAcceptable(from: Option[A], ordering: Ordering[A])(a: A): Boolean = - from.map(x => ordering.gteq(a, x)).getOrElse(true) - - private def isRightAcceptable(until: Option[A], ordering: Ordering[A])(a: A): Boolean = - until.map(x => ordering.lt(a, x)).getOrElse(true) - - /** - * Cardinality store the set size, unfortunately a - * set view (given by rangeImpl) - * cannot take advantage of this optimisation - * - */ - override def size: Int = base.map(_ => super.size).getOrElse(cardinality) + override def size: Int = RB.countInRange(treeRef.elem, from, until) override def stringPrefix = "TreeSet" override def empty: TreeSet[A] = TreeSet.empty - override def rangeImpl(from: Option[A], until: Option[A]): TreeSet[A] = new TreeSet(Some(this), from, until) + private def pickBound(comparison: (A, A) => A, oldBound: Option[A], newBound: Option[A]) = (newBound, oldBound) match { + case (Some(newB), Some(oldB)) => Some(comparison(newB, oldB)) + case (None, _) => oldBound + case _ => newBound + } + + override def rangeImpl(fromArg: Option[A], untilArg: Option[A]): TreeSet[A] = { + val newFrom = pickBound(ordering.max, fromArg, from) + val newUntil = pickBound(ordering.min, untilArg, until) + + new TreeSet(treeRef, newFrom, newUntil) + } override def -=(elem: A): this.type = { - try { - resolve.avl = resolve.avl.remove(elem, ordering) - resolve.cardinality = resolve.cardinality - 1 - } catch { - case e: NoSuchElementException => () - } + treeRef.elem = RB.delete(treeRef.elem, elem) this } override def +=(elem: A): this.type = { - try { - resolve.avl = resolve.avl.insert(elem, ordering) - resolve.cardinality = resolve.cardinality + 1 - } catch { - case e: IllegalArgumentException => () - } + treeRef.elem = RB.update(treeRef.elem, elem, null, false) this } /** * Thanks to the immutable nature of the - * underlying AVL Tree, we can share it with + * underlying Tree, we can share it with * the clone. So clone complexity in time is O(1). * */ - override def clone(): TreeSet[A] = { - val clone = new TreeSet[A](base, from, until) - clone.avl = resolve.avl - clone.cardinality = resolve.cardinality - clone - } + override def clone(): TreeSet[A] = + new TreeSet[A](new ObjectRef(treeRef.elem), from, until) + + private val notProjection = !(from.isDefined || until.isDefined) override def contains(elem: A): Boolean = { - isLeftAcceptable(from, ordering)(elem) && - isRightAcceptable(until, ordering)(elem) && - resolve.avl.contains(elem, ordering) - } + def leftAcceptable: Boolean = from match { + case Some(lb) => ordering.gteq(elem, lb) + case _ => true + } - override def iterator: Iterator[A] = resolve.avl.iterator - .dropWhile(e => !isLeftAcceptable(from, ordering)(e)) - .takeWhile(e => isRightAcceptable(until, ordering)(e)) + def rightAcceptable: Boolean = until match { + case Some(ub) => ordering.lt(elem, ub) + case _ => true + } + + (notProjection || (leftAcceptable && rightAcceptable)) && + RB.contains(treeRef.elem, elem) + } + override def iterator: Iterator[A] = iteratorFrom(None) + + override def keysIteratorFrom(start: A) = iteratorFrom(Some(start)) + + private def iteratorFrom(start: Option[A]) = { + val it = RB.keysIterator(treeRef.elem, pickBound(ordering.max, from, start)) + until match { + case None => it + case Some(ub) => it takeWhile (k => ordering.lt(k, ub)) + } + } } |