diff options
Diffstat (limited to 'src')
20 files changed, 229 insertions, 160 deletions
diff --git a/src/compiler/scala/reflect/macros/contexts/Parsers.scala b/src/compiler/scala/reflect/macros/contexts/Parsers.scala index f4584f3627..cc3f01e53b 100644 --- a/src/compiler/scala/reflect/macros/contexts/Parsers.scala +++ b/src/compiler/scala/reflect/macros/contexts/Parsers.scala @@ -16,8 +16,9 @@ trait Parsers { val tree = gen.mkTreeOrBlock(parser.parseStatsOrPackages()) sreporter.infos.foreach { case sreporter.Info(pos, msg, sreporter.ERROR) => throw ParseException(pos, msg) + case _ => } tree } finally global.reporter = oldReporter } -}
\ No newline at end of file +} diff --git a/src/compiler/scala/tools/nsc/backend/jvm/opt/ClosureOptimizer.scala b/src/compiler/scala/tools/nsc/backend/jvm/opt/ClosureOptimizer.scala index f98a08a6a9..b8547e1dc6 100644 --- a/src/compiler/scala/tools/nsc/backend/jvm/opt/ClosureOptimizer.scala +++ b/src/compiler/scala/tools/nsc/backend/jvm/opt/ClosureOptimizer.scala @@ -27,6 +27,22 @@ class ClosureOptimizer[BT <: BTypes](val btypes: BT) { import backendUtils._ import ClosureOptimizer._ + private object closureInitOrdering extends Ordering[ClosureInstantiation] { + override def compare(x: ClosureInstantiation, y: ClosureInstantiation): Int = { + val cls = x.ownerClass.internalName compareTo y.ownerClass.internalName + if (cls != 0) return cls + + val mName = x.ownerMethod.name compareTo y.ownerMethod.name + if (mName != 0) return mName + + val mDesc = x.ownerMethod.desc compareTo y.ownerMethod.desc + if (mDesc != 0) return mDesc + + def pos(inst: ClosureInstantiation) = inst.ownerMethod.instructions.indexOf(inst.lambdaMetaFactoryCall.indy) + pos(x) - pos(y) + } + } + /** * If a closure is allocated and invoked within the same method, re-write the invocation to the * closure body method. @@ -57,27 +73,12 @@ class ClosureOptimizer[BT <: BTypes](val btypes: BT) { * [invoke the closure body method] */ def rewriteClosureApplyInvocations(): Unit = { - implicit object closureInitOrdering extends Ordering[ClosureInstantiation] { - override def compare(x: ClosureInstantiation, y: ClosureInstantiation): Int = { - val cls = x.ownerClass.internalName compareTo y.ownerClass.internalName - if (cls != 0) return cls - val mName = x.ownerMethod.name compareTo y.ownerMethod.name - if (mName != 0) return mName - - val mDesc = x.ownerMethod.desc compareTo y.ownerMethod.desc - if (mDesc != 0) return mDesc - - def pos(inst: ClosureInstantiation) = inst.ownerMethod.instructions.indexOf(inst.lambdaMetaFactoryCall.indy) - pos(x) - pos(y) - } - } - - // Use collections that keep insertion order, ensures order of closure rewrites (bytecode stability) - val toRewrite = mutable.LinkedHashMap.empty[ClosureInstantiation, mutable.ArrayBuffer[(MethodInsnNode, Int)]] - def addRewrite(init: ClosureInstantiation, invocation: MethodInsnNode, stackHeight: Int) = { - val calls = toRewrite.getOrElseUpdate(init, mutable.ArrayBuffer.empty[(MethodInsnNode, Int)]) - calls += ((invocation, stackHeight)) + // sort all closure invocations to rewrite to ensure bytecode stability + val toRewrite = mutable.TreeMap.empty[ClosureInstantiation, mutable.ArrayBuffer[(MethodInsnNode, Int)]](closureInitOrdering) + def addRewrite(init: ClosureInstantiation, invocation: MethodInsnNode, stackHeight: Int): Unit = { + val callsites = toRewrite.getOrElseUpdate(init, mutable.ArrayBuffer.empty[(MethodInsnNode, Int)]) + callsites += ((invocation, stackHeight)) } // For each closure instantiation find callsites of the closure and add them to the toRewrite @@ -98,20 +99,12 @@ class ClosureOptimizer[BT <: BTypes](val btypes: BT) { // A lazy val to ensure the analysis only runs if necessary (the value is passed by name to `closureCallsites`) lazy val prodCons = new ProdConsAnalyzer(method, ownerClass) - // sorting for bytecode stability (e.g. indices of local vars created during the rewrite) - val sortedInits = immutable.TreeSet.empty ++ closureInits.values - - for (init <- sortedInits) { - val callsites = closureCallsites(init, prodCons) - if (callsites.nonEmpty) { - callsites foreach { - case Left(warning) => - backendReporting.inlinerWarning(warning.pos, warning.toString) + for (init <- closureInits.valuesIterator) closureCallsites(init, prodCons) foreach { + case Left(warning) => + backendReporting.inlinerWarning(warning.pos, warning.toString) - case Right((invocation, stackHeight)) => - addRewrite(init, invocation, stackHeight) - } - } + case Right((invocation, stackHeight)) => + addRewrite(init, invocation, stackHeight) } case _ => @@ -120,11 +113,11 @@ class ClosureOptimizer[BT <: BTypes](val btypes: BT) { case _ => } - toRewrite foreach { - case (closureInit, invocations) => - // Local variables that hold the captured values and the closure invocation arguments. - val (localsForCapturedValues, argumentLocalsList) = localsForClosureRewrite(closureInit) - for ((invocation, stackHeight) <- invocations) rewriteClosureApplyInvocation(closureInit, invocation, stackHeight, localsForCapturedValues, argumentLocalsList) + for ((closureInit, invocations) <- toRewrite) { + // Local variables that hold the captured values and the closure invocation arguments. + val (localsForCapturedValues, argumentLocalsList) = localsForClosureRewrite(closureInit) + for ((invocation, stackHeight) <- invocations) + rewriteClosureApplyInvocation(closureInit, invocation, stackHeight, localsForCapturedValues, argumentLocalsList) } } diff --git a/src/compiler/scala/tools/nsc/transform/patmat/Logic.scala b/src/compiler/scala/tools/nsc/transform/patmat/Logic.scala index 1a4df9973e..8b2e09495f 100644 --- a/src/compiler/scala/tools/nsc/transform/patmat/Logic.scala +++ b/src/compiler/scala/tools/nsc/transform/patmat/Logic.scala @@ -691,7 +691,7 @@ trait ScalaLogic extends Interface with Logic with TreeAndTypeAnalysis { // if X is mutable. freshExistentialSubtype(t.tpe) } - else trees find (a => a.correspondsStructure(t)(sameValue)) match { + else trees find (a => equivalentTree(a, t)) match { case Some(orig) => debug.patmat("unique tp for tree: " + ((orig, orig.tpe))) orig.tpe diff --git a/src/compiler/scala/tools/nsc/transform/patmat/MatchAnalysis.scala b/src/compiler/scala/tools/nsc/transform/patmat/MatchAnalysis.scala index affbcf9ec8..ab3b25e76b 100644 --- a/src/compiler/scala/tools/nsc/transform/patmat/MatchAnalysis.scala +++ b/src/compiler/scala/tools/nsc/transform/patmat/MatchAnalysis.scala @@ -84,11 +84,15 @@ trait TreeAndTypeAnalysis extends Debugging { tp <:< tpImpliedNormalizedToAny } - // TODO: improve, e.g., for constants - def sameValue(a: Tree, b: Tree): Boolean = (a eq b) || ((a, b) match { - case (_ : Ident, _ : Ident) => a.symbol eq b.symbol - case _ => false - }) + def equivalentTree(a: Tree, b: Tree): Boolean = (a, b) match { + case (Select(qual1, _), Select(qual2, _)) => equivalentTree(qual1, qual2) && a.symbol == b.symbol + case (Ident(_), Ident(_)) => a.symbol == b.symbol + case (Literal(c1), Literal(c2)) => c1 == c2 + case (This(_), This(_)) => a.symbol == b.symbol + case (Apply(fun1, args1), Apply(fun2, args2)) => equivalentTree(fun1, fun2) && args1.corresponds(args2)(equivalentTree) + // Those are the only cases we need to handle in the pattern matcher + case _ => false + } trait CheckableTreeAndTypeAnalysis { val typer: Typer @@ -172,6 +176,8 @@ trait TreeAndTypeAnalysis extends Debugging { filterChildren(subclasses) }) } + case sym if sym.isCase => + List(List(tp)) case sym => debug.patmat("enum unsealed "+ ((tp, sym, sym.isSealed, isPrimitiveValueClass(sym)))) @@ -276,7 +282,7 @@ trait MatchApproximation extends TreeAndTypeAnalysis with ScalaLogic with MatchT // hashconsing trees (modulo value-equality) def unique(t: Tree, tpOverride: Type = NoType): Tree = - trees find (a => a.correspondsStructure(t)(sameValue)) match { + trees find (a => equivalentTree(a, t)) match { case Some(orig) => // debug.patmat("unique: "+ (t eq orig, orig)) orig diff --git a/src/compiler/scala/tools/nsc/typechecker/Typers.scala b/src/compiler/scala/tools/nsc/typechecker/Typers.scala index 84af9233e1..3a8edafd58 100644 --- a/src/compiler/scala/tools/nsc/typechecker/Typers.scala +++ b/src/compiler/scala/tools/nsc/typechecker/Typers.scala @@ -1860,7 +1860,7 @@ trait Typers extends Adaptations with Tags with TypersTracking with PatternTyper clazz.annotations.map(_.completeInfo()) if (templ.symbol == NoSymbol) templ setSymbol clazz.newLocalDummy(templ.pos) - val self1 = templ.self match { + val self1 = (templ.self: @unchecked) match { case vd @ ValDef(_, _, tpt, EmptyTree) => val tpt1 = checkNoEscaping.privates( clazz.thisSym, @@ -5421,6 +5421,9 @@ trait Typers extends Adaptations with Tags with TypersTracking with PatternTyper if (!isPastTyper) signalDone(context.asInstanceOf[analyzer.Context], tree, result) + if (mode.inPatternMode && !mode.inPolyMode && result.isType) + PatternMustBeValue(result, pt) + result } @@ -5510,10 +5513,7 @@ trait Typers extends Adaptations with Tags with TypersTracking with PatternTyper // as a compromise, context.enrichmentEnabled tells adaptToMember to go ahead and enrich, // but arbitrary conversions (in adapt) are disabled // TODO: can we achieve the pattern matching bit of the string interpolation SIP without this? - typingInPattern(context.withImplicitsDisabledAllowEnrichment(typed(tree, PATTERNmode, pt))) match { - case tpt if tpt.isType => PatternMustBeValue(tpt, pt); tpt - case pat => pat - } + typingInPattern(context.withImplicitsDisabledAllowEnrichment(typed(tree, PATTERNmode, pt))) } /** Types a (fully parameterized) type tree */ diff --git a/src/library/scala/collection/immutable/ListSet.scala b/src/library/scala/collection/immutable/ListSet.scala index a65e25ed6e..98b91f7c84 100644 --- a/src/library/scala/collection/immutable/ListSet.scala +++ b/src/library/scala/collection/immutable/ListSet.scala @@ -12,7 +12,7 @@ package immutable import generic._ import scala.annotation.tailrec -import mutable.Builder +import mutable.{Builder, ReusableBuilder} /** $factoryInfo * @define Coll immutable.ListSet @@ -32,8 +32,10 @@ object ListSet extends ImmutableSetFactory[ListSet] { * a time to a list backed set puts the "squared" in N^2. There is a * temporary space cost, but it's improbable a list backed set could * become large enough for this to matter given its pricy element lookup. + * + * This builder is reusable. */ - class ListSetBuilder[Elem](initial: ListSet[Elem]) extends Builder[Elem, ListSet[Elem]] { + class ListSetBuilder[Elem](initial: ListSet[Elem]) extends ReusableBuilder[Elem, ListSet[Elem]] { def this() = this(empty[Elem]) protected val elems = (new mutable.ListBuffer[Elem] ++= initial).reverse protected val seen = new mutable.HashSet[Elem] ++= initial diff --git a/src/library/scala/collection/immutable/Vector.scala b/src/library/scala/collection/immutable/Vector.scala index cd2d3f843b..754196e6c1 100644 --- a/src/library/scala/collection/immutable/Vector.scala +++ b/src/library/scala/collection/immutable/Vector.scala @@ -13,7 +13,7 @@ package immutable import scala.annotation.unchecked.uncheckedVariance import scala.compat.Platform import scala.collection.generic._ -import scala.collection.mutable.Builder +import scala.collection.mutable.{Builder, ReusableBuilder} import scala.collection.parallel.immutable.ParVector /** Companion object to the Vector class @@ -704,8 +704,8 @@ extends AbstractIterator[A] } } - -final class VectorBuilder[A]() extends Builder[A,Vector[A]] with VectorPointer[A @uncheckedVariance] { +/** A class to build instances of `Vector`. This builder is reusable. */ +final class VectorBuilder[A]() extends ReusableBuilder[A,Vector[A]] with VectorPointer[A @uncheckedVariance] { // possible alternative: start with display0 = null, blockIndex = -32, lo = 32 // to avoid allocating initial array if the result will be empty anyways diff --git a/src/library/scala/collection/mutable/AnyRefMap.scala b/src/library/scala/collection/mutable/AnyRefMap.scala index af7600ad3d..2ed5bbea60 100644 --- a/src/library/scala/collection/mutable/AnyRefMap.scala +++ b/src/library/scala/collection/mutable/AnyRefMap.scala @@ -427,7 +427,11 @@ object AnyRefMap { def apply(): AnyRefMapBuilder[J, U] = new AnyRefMapBuilder[J, U] } - final class AnyRefMapBuilder[K <: AnyRef, V] extends Builder[(K, V), AnyRefMap[K, V]] { + /** A builder for instances of `AnyRefMap`. + * + * This builder can be reused to create multiple instances. + */ + final class AnyRefMapBuilder[K <: AnyRef, V] extends ReusableBuilder[(K, V), AnyRefMap[K, V]] { private[collection] var elems: AnyRefMap[K, V] = new AnyRefMap[K, V] def +=(entry: (K, V)): this.type = { elems += entry diff --git a/src/library/scala/collection/mutable/ArrayBuilder.scala b/src/library/scala/collection/mutable/ArrayBuilder.scala index ac78ab823b..549ffef565 100644 --- a/src/library/scala/collection/mutable/ArrayBuilder.scala +++ b/src/library/scala/collection/mutable/ArrayBuilder.scala @@ -18,7 +18,7 @@ import scala.reflect.ClassTag * * @tparam T the type of the elements for the builder. */ -abstract class ArrayBuilder[T] extends Builder[T, Array[T]] with Serializable +abstract class ArrayBuilder[T] extends ReusableBuilder[T, Array[T]] with Serializable /** A companion object for array builders. * @@ -49,6 +49,8 @@ object ArrayBuilder { /** A class for array builders for arrays of reference types. * + * This builder can be reused. + * * @tparam T type of elements for the array builder, subtype of `AnyRef` with a `ClassTag` context bound. */ @deprecatedInheritance("ArrayBuilder.ofRef is an internal implementation not intended for subclassing.", "2.11.0") @@ -98,12 +100,13 @@ object ArrayBuilder { super.++=(xs) } - def clear() { - size = 0 - } + def clear() { size = 0 } def result() = { - if (capacity != 0 && capacity == size) elems + if (capacity != 0 && capacity == size) { + capacity = 0 + elems + } else mkArray(size) } @@ -115,7 +118,7 @@ object ArrayBuilder { override def toString = "ArrayBuilder.ofRef" } - /** A class for array builders for arrays of `byte`s. */ + /** A class for array builders for arrays of `byte`s. It can be reused. */ @deprecatedInheritance("ArrayBuilder.ofByte is an internal implementation not intended for subclassing.", "2.11.0") class ofByte extends ArrayBuilder[Byte] { @@ -163,12 +166,13 @@ object ArrayBuilder { super.++=(xs) } - def clear() { - size = 0 - } + def clear() { size = 0 } def result() = { - if (capacity != 0 && capacity == size) elems + if (capacity != 0 && capacity == size) { + capacity = 0 + elems + } else mkArray(size) } @@ -180,7 +184,7 @@ object ArrayBuilder { override def toString = "ArrayBuilder.ofByte" } - /** A class for array builders for arrays of `short`s. */ + /** A class for array builders for arrays of `short`s. It can be reused. */ @deprecatedInheritance("ArrayBuilder.ofShort is an internal implementation not intended for subclassing.", "2.11.0") class ofShort extends ArrayBuilder[Short] { @@ -228,12 +232,13 @@ object ArrayBuilder { super.++=(xs) } - def clear() { - size = 0 - } + def clear() { size = 0 } def result() = { - if (capacity != 0 && capacity == size) elems + if (capacity != 0 && capacity == size) { + capacity = 0 + elems + } else mkArray(size) } @@ -245,7 +250,7 @@ object ArrayBuilder { override def toString = "ArrayBuilder.ofShort" } - /** A class for array builders for arrays of `char`s. */ + /** A class for array builders for arrays of `char`s. It can be reused. */ @deprecatedInheritance("ArrayBuilder.ofChar is an internal implementation not intended for subclassing.", "2.11.0") class ofChar extends ArrayBuilder[Char] { @@ -293,12 +298,13 @@ object ArrayBuilder { super.++=(xs) } - def clear() { - size = 0 - } + def clear() { size = 0 } def result() = { - if (capacity != 0 && capacity == size) elems + if (capacity != 0 && capacity == size) { + capacity = 0 + elems + } else mkArray(size) } @@ -310,7 +316,7 @@ object ArrayBuilder { override def toString = "ArrayBuilder.ofChar" } - /** A class for array builders for arrays of `int`s. */ + /** A class for array builders for arrays of `int`s. It can be reused. */ @deprecatedInheritance("ArrayBuilder.ofInt is an internal implementation not intended for subclassing.", "2.11.0") class ofInt extends ArrayBuilder[Int] { @@ -358,12 +364,13 @@ object ArrayBuilder { super.++=(xs) } - def clear() { - size = 0 - } + def clear() { size = 0 } def result() = { - if (capacity != 0 && capacity == size) elems + if (capacity != 0 && capacity == size) { + capacity = 0 + elems + } else mkArray(size) } @@ -375,7 +382,7 @@ object ArrayBuilder { override def toString = "ArrayBuilder.ofInt" } - /** A class for array builders for arrays of `long`s. */ + /** A class for array builders for arrays of `long`s. It can be reused. */ @deprecatedInheritance("ArrayBuilder.ofLong is an internal implementation not intended for subclassing.", "2.11.0") class ofLong extends ArrayBuilder[Long] { @@ -423,12 +430,13 @@ object ArrayBuilder { super.++=(xs) } - def clear() { - size = 0 - } + def clear() { size = 0 } def result() = { - if (capacity != 0 && capacity == size) elems + if (capacity != 0 && capacity == size) { + capacity = 0 + elems + } else mkArray(size) } @@ -440,7 +448,7 @@ object ArrayBuilder { override def toString = "ArrayBuilder.ofLong" } - /** A class for array builders for arrays of `float`s. */ + /** A class for array builders for arrays of `float`s. It can be reused. */ @deprecatedInheritance("ArrayBuilder.ofFloat is an internal implementation not intended for subclassing.", "2.11.0") class ofFloat extends ArrayBuilder[Float] { @@ -488,12 +496,13 @@ object ArrayBuilder { super.++=(xs) } - def clear() { - size = 0 - } + def clear() { size = 0 } def result() = { - if (capacity != 0 && capacity == size) elems + if (capacity != 0 && capacity == size) { + capacity = 0 + elems + } else mkArray(size) } @@ -505,7 +514,7 @@ object ArrayBuilder { override def toString = "ArrayBuilder.ofFloat" } - /** A class for array builders for arrays of `double`s. */ + /** A class for array builders for arrays of `double`s. It can be reused. */ @deprecatedInheritance("ArrayBuilder.ofDouble is an internal implementation not intended for subclassing.", "2.11.0") class ofDouble extends ArrayBuilder[Double] { @@ -553,12 +562,13 @@ object ArrayBuilder { super.++=(xs) } - def clear() { - size = 0 - } + def clear() { size = 0 } def result() = { - if (capacity != 0 && capacity == size) elems + if (capacity != 0 && capacity == size) { + capacity = 0 + elems + } else mkArray(size) } @@ -570,7 +580,7 @@ object ArrayBuilder { override def toString = "ArrayBuilder.ofDouble" } - /** A class for array builders for arrays of `boolean`s. */ + /** A class for array builders for arrays of `boolean`s. It can be reused. */ class ofBoolean extends ArrayBuilder[Boolean] { private var elems: Array[Boolean] = _ @@ -617,12 +627,13 @@ object ArrayBuilder { super.++=(xs) } - def clear() { - size = 0 - } + def clear() { size = 0 } def result() = { - if (capacity != 0 && capacity == size) elems + if (capacity != 0 && capacity == size) { + capacity = 0 + elems + } else mkArray(size) } @@ -634,65 +645,33 @@ object ArrayBuilder { override def toString = "ArrayBuilder.ofBoolean" } - /** A class for array builders for arrays of `Unit` type. */ + /** A class for array builders for arrays of `Unit` type. It can be reused. */ @deprecatedInheritance("ArrayBuilder.ofUnit is an internal implementation not intended for subclassing.", "2.11.0") class ofUnit extends ArrayBuilder[Unit] { - private var elems: Array[Unit] = _ - private var capacity: Int = 0 private var size: Int = 0 - private def mkArray(size: Int): Array[Unit] = { - val newelems = new Array[Unit](size) - if (this.size > 0) Array.copy(elems, 0, newelems, 0, this.size) - newelems - } - - private def resize(size: Int) { - elems = mkArray(size) - capacity = size - } - - override def sizeHint(size: Int) { - if (capacity < size) resize(size) - } - - private def ensureSize(size: Int) { - if (capacity < size || capacity == 0) { - var newsize = if (capacity == 0) 16 else capacity * 2 - while (newsize < size) newsize *= 2 - resize(newsize) - } - } - def +=(elem: Unit): this.type = { - ensureSize(size + 1) - elems(size) = elem size += 1 this } - override def ++=(xs: TraversableOnce[Unit]): this.type = xs match { - case xs: WrappedArray.ofUnit => - ensureSize(this.size + xs.length) - Array.copy(xs.array, 0, elems, this.size, xs.length) - size += xs.length - this - case _ => - super.++=(xs) + override def ++=(xs: TraversableOnce[Unit]): this.type = { + size += xs.size + this } - def clear() { - size = 0 - } + def clear() { size = 0 } def result() = { - if (capacity != 0 && capacity == size) elems - else mkArray(size) + val ans = new Array[Unit](size) + var i = 0 + while (i < size) { ans(i) = (); i += 1 } + ans } override def equals(other: Any): Boolean = other match { - case x: ofUnit => (size == x.size) && (elems == x.elems) + case x: ofUnit => (size == x.size) case _ => false } diff --git a/src/library/scala/collection/mutable/Builder.scala b/src/library/scala/collection/mutable/Builder.scala index 75560580cc..8d6a0ec69d 100644 --- a/src/library/scala/collection/mutable/Builder.scala +++ b/src/library/scala/collection/mutable/Builder.scala @@ -18,6 +18,14 @@ import generic._ * elements to the builder with `+=` and then converting to the required * collection type with `result`. * + * One cannot assume that a single `Builder` can build more than one + * instance of the desired collection. Particular subclasses may allow + * such behavior. Otherwise, `result` should be treated as a terminal + * operation: after it is called, no further methods should be called on + * the builder. Extend the [[collection.mutable.ReusableBuilder]] trait + * instead of `Builder` for builders that may be reused to build multiple + * instances. + * * @tparam Elem the type of elements that get added to the builder. * @tparam To the type of collection that it produced. * @@ -36,8 +44,10 @@ trait Builder[-Elem, +To] extends Growable[Elem] { */ def clear() - /** Produces a collection from the added elements. - * The builder's contents are undefined after this operation. + /** Produces a collection from the added elements. This is a terminal operation: + * the builder's contents are undefined after this operation, and no further + * methods should be called. + * * @return a collection containing the elements added to this builder. */ def result(): To @@ -112,6 +122,8 @@ trait Builder[-Elem, +To] extends Growable[Elem] { * @tparam NewTo the type of collection returned by `f`. * @return a new builder which is the same as the current builder except * that a transformation function is applied to this builder's result. + * + * @note The original builder should no longer be used after `mapResult` is called. */ def mapResult[NewTo](f: To => NewTo): Builder[Elem, NewTo] = new Builder[Elem, NewTo] with Proxy { diff --git a/src/library/scala/collection/mutable/GrowingBuilder.scala b/src/library/scala/collection/mutable/GrowingBuilder.scala index c4b5e546aa..27d554d98e 100644 --- a/src/library/scala/collection/mutable/GrowingBuilder.scala +++ b/src/library/scala/collection/mutable/GrowingBuilder.scala @@ -15,6 +15,8 @@ import generic._ /** The canonical builder for collections that are growable, i.e. that support an * efficient `+=` method which adds an element to the collection. * + * GrowableBuilders can produce only a single instance of the collection they are growing. + * * @author Paul Phillips * @version 2.8 * @since 2.8 @@ -25,6 +27,6 @@ import generic._ class GrowingBuilder[Elem, To <: Growable[Elem]](empty: To) extends Builder[Elem, To] { protected var elems: To = empty def +=(x: Elem): this.type = { elems += x; this } - def clear() { elems = empty } + def clear() { empty.clear } def result: To = elems } diff --git a/src/library/scala/collection/mutable/LazyBuilder.scala b/src/library/scala/collection/mutable/LazyBuilder.scala index ebee38b77f..f0a5e6971a 100644 --- a/src/library/scala/collection/mutable/LazyBuilder.scala +++ b/src/library/scala/collection/mutable/LazyBuilder.scala @@ -13,12 +13,14 @@ package mutable /** A builder that constructs its result lazily. Iterators or iterables to * be added to this builder with `++=` are not evaluated until `result` is called. * + * This builder can be reused. + * * @since 2.8 * * @tparam Elem type of the elements for this builder. * @tparam To type of the collection this builder builds. */ -abstract class LazyBuilder[Elem, +To] extends Builder[Elem, To] { +abstract class LazyBuilder[Elem, +To] extends ReusableBuilder[Elem, To] { /** The different segments of elements to be added to the builder, represented as iterators */ protected var parts = new ListBuffer[TraversableOnce[Elem]] def +=(x: Elem): this.type = { parts += List(x); this } diff --git a/src/library/scala/collection/mutable/ListBuffer.scala b/src/library/scala/collection/mutable/ListBuffer.scala index 0a483ceb86..02fcced3ac 100644 --- a/src/library/scala/collection/mutable/ListBuffer.scala +++ b/src/library/scala/collection/mutable/ListBuffer.scala @@ -46,7 +46,7 @@ final class ListBuffer[A] with Buffer[A] with GenericTraversableTemplate[A, ListBuffer] with BufferLike[A, ListBuffer[A]] - with Builder[A, List[A]] + with ReusableBuilder[A, List[A]] with SeqForwarder[A] with Serializable { @@ -297,6 +297,10 @@ final class ListBuffer[A] // Implementation of abstract method in Builder + /** Returns the accumulated `List`. + * + * This method may be called multiple times to obtain snapshots of the list in different stages of construction. + */ def result: List[A] = toList /** Converts this buffer to a list. Takes constant time. The buffer is diff --git a/src/library/scala/collection/mutable/LongMap.scala b/src/library/scala/collection/mutable/LongMap.scala index f39a6ba634..ecbb1952af 100644 --- a/src/library/scala/collection/mutable/LongMap.scala +++ b/src/library/scala/collection/mutable/LongMap.scala @@ -519,7 +519,11 @@ object LongMap { def apply(): LongMapBuilder[U] = new LongMapBuilder[U] } - final class LongMapBuilder[V] extends Builder[(Long, V), LongMap[V]] { + /** A builder for instances of `LongMap`. + * + * This builder can be reused to create multiple instances. + */ + final class LongMapBuilder[V] extends ReusableBuilder[(Long, V), LongMap[V]] { private[collection] var elems: LongMap[V] = new LongMap[V] def +=(entry: (Long, V)): this.type = { elems += entry diff --git a/src/library/scala/collection/mutable/MapBuilder.scala b/src/library/scala/collection/mutable/MapBuilder.scala index a5a6b12ea9..cfc3079f41 100644 --- a/src/library/scala/collection/mutable/MapBuilder.scala +++ b/src/library/scala/collection/mutable/MapBuilder.scala @@ -23,7 +23,7 @@ package mutable * @since 2.8 */ class MapBuilder[A, B, Coll <: scala.collection.GenMap[A, B] with scala.collection.GenMapLike[A, B, Coll]](empty: Coll) -extends Builder[(A, B), Coll] { +extends ReusableBuilder[(A, B), Coll] { protected var elems: Coll = empty def +=(x: (A, B)): this.type = { elems = (elems + x).asInstanceOf[Coll] diff --git a/src/library/scala/collection/mutable/ReusableBuilder.scala b/src/library/scala/collection/mutable/ReusableBuilder.scala new file mode 100644 index 0000000000..caab3071b6 --- /dev/null +++ b/src/library/scala/collection/mutable/ReusableBuilder.scala @@ -0,0 +1,51 @@ +/* __ *\ +** ________ ___ / / ___ Scala API ** +** / __/ __// _ | / / / _ | (c) 2003-2016, LAMP/EPFL ** +** __\ \/ /__/ __ |/ /__/ __ | http://scala-lang.org/ ** +** /____/\___/_/ |_/____/_/ | | ** +** |/ ** +\* */ + + +package scala +package collection +package mutable + +import generic._ + +/** `ReusableBuilder` is a marker trait that indicates that a `Builder` + * can be reused to build more than one instance of a collection. In + * particular, calling `result` followed by `clear` will produce a + * collection and reset the builder to begin building a new collection + * of the same type. + * + * It is up to subclasses to implement this behavior, and to document any + * other behavior that varies from standard `ReusableBuilder` usage + * (e.g. operations being well-defined after a call to `result`, or allowing + * multiple calls to result to obtain different snapshots of a collection under + * construction). + * + * @tparam Elem the type of elements that get added to the builder. + * @tparam To the type of collection that it produced. + * + * @since 2.12 + */ +trait ReusableBuilder[-Elem, +To] extends Builder[Elem, To] { + /** Clears the contents of this builder. + * After execution of this method, the builder will contain no elements. + * + * If executed immediately after a call to `result`, this allows a new + * instance of the same type of collection to be built. + */ + override def clear(): Unit // Note: overriding for scaladoc only! + + /** Produces a collection from the added elements. + * + * After a call to `result`, the behavior of all other methods is undefined + * save for `clear`. If `clear` is called, then the builder is reset and + * may be used to build another instance. + * + * @return a collection containing the elements added to this builder. + */ + override def result(): To // Note: overriding for scaladoc only! +} diff --git a/src/library/scala/collection/mutable/SetBuilder.scala b/src/library/scala/collection/mutable/SetBuilder.scala index 01bfdc96ed..5d1e9ffc3a 100644 --- a/src/library/scala/collection/mutable/SetBuilder.scala +++ b/src/library/scala/collection/mutable/SetBuilder.scala @@ -17,7 +17,9 @@ package mutable * @param empty The empty element of the collection. * @since 2.8 */ -class SetBuilder[A, Coll <: scala.collection.Set[A] with scala.collection.SetLike[A, Coll]](empty: Coll) extends Builder[A, Coll] { +class SetBuilder[A, Coll <: scala.collection.Set[A] +with scala.collection.SetLike[A, Coll]](empty: Coll) +extends ReusableBuilder[A, Coll] { protected var elems: Coll = empty def +=(x: A): this.type = { elems = elems + x; this } def clear() { elems = empty } diff --git a/src/library/scala/collection/mutable/StringBuilder.scala b/src/library/scala/collection/mutable/StringBuilder.scala index c56d40786e..b5b9498374 100644 --- a/src/library/scala/collection/mutable/StringBuilder.scala +++ b/src/library/scala/collection/mutable/StringBuilder.scala @@ -33,7 +33,7 @@ final class StringBuilder(private val underlying: JavaStringBuilder) with java.lang.CharSequence with IndexedSeq[Char] with StringLike[StringBuilder] - with Builder[Char, String] + with ReusableBuilder[Char, String] with Serializable { override protected[this] def thisCollection: StringBuilder = this @@ -435,7 +435,11 @@ final class StringBuilder(private val underlying: JavaStringBuilder) */ override def mkString = toString - /** Returns the result of this Builder (a String) + /** Returns the result of this Builder (a String). + * + * If this method is called multiple times, each call will result in a snapshot of the buffer at that point in time. + * In particular, a `StringBuilder` can be used to build multiple independent strings by emptying the buffer with `clear` + * after each call to `result`. * * @return the string assembled by this StringBuilder */ diff --git a/src/library/scala/collection/mutable/WrappedArrayBuilder.scala b/src/library/scala/collection/mutable/WrappedArrayBuilder.scala index bfe95a11ab..c4781321d7 100644 --- a/src/library/scala/collection/mutable/WrappedArrayBuilder.scala +++ b/src/library/scala/collection/mutable/WrappedArrayBuilder.scala @@ -17,12 +17,14 @@ import scala.runtime.ScalaRunTime._ /** A builder class for arrays. * + * This builder can be reused. + * * @tparam A type of elements that can be added to this builder. * @param tag class tag for objects of type `A`. * * @since 2.8 */ -class WrappedArrayBuilder[A](tag: ClassTag[A]) extends Builder[A, WrappedArray[A]] { +class WrappedArrayBuilder[A](tag: ClassTag[A]) extends ReusableBuilder[A, WrappedArray[A]] { @deprecated("use tag instead", "2.10.0") val manifest: ClassTag[A] = tag @@ -73,12 +75,13 @@ class WrappedArrayBuilder[A](tag: ClassTag[A]) extends Builder[A, WrappedArray[A this } - def clear() { - size = 0 - } + def clear() { size = 0 } def result() = { - if (capacity != 0 && capacity == size) elems + if (capacity != 0 && capacity == size) { + capacity = 0 + elems + } else mkArray(size) } diff --git a/src/scaladoc/scala/tools/nsc/doc/html/page/Template.scala b/src/scaladoc/scala/tools/nsc/doc/html/page/Template.scala index e0cfbc9334..05724a879a 100644 --- a/src/scaladoc/scala/tools/nsc/doc/html/page/Template.scala +++ b/src/scaladoc/scala/tools/nsc/doc/html/page/Template.scala @@ -624,7 +624,7 @@ class Template(universe: doc.Universe, generator: DiagramGenerator, tpl: DocTemp <dt>To do</dt> <dd>{ val todoXml: List[NodeSeq] = (for(todo <- comment.todo ) yield <span class="cmt">{bodyToHtml(todo)}</span> ) - todoXml.reduceLeft(_ ++ Text(", ") ++ _) + todoXml.reduceLeft(_ ++ _) }</dd> } |