Some accumulated cleanup done while profiling a...

Some accumulated cleanup done while profiling and reducing uses of
length. No review.

22 files changed, 68 insertions, 112 deletions

diff --git a/src/compiler/scala/tools/nsc/ast/parser/SymbolicXMLBuilder.scala b/src/compiler/scala/tools/nsc/ast/parser/SymbolicXMLBuilder.scala
index 81bb5db286..a78e46ea84 100644
--- a/src/compiler/scala/tools/nsc/ast/parser/SymbolicXMLBuilder.scala
+++ b/src/compiler/scala/tools/nsc/ast/parser/SymbolicXMLBuilder.scala
@@ -6,7 +6,7 @@
 package scala.tools.nsc
 package ast.parser
 
-import collection.mutable.Map
+import scala.collection.{ mutable, immutable }
 import xml.{ EntityRef, Text }
 import xml.XML.{ xmlns }
 import symtab.Flags.MUTABLE
@@ -184,7 +184,7 @@ abstract class SymbolicXMLBuilder(p: Parsers#Parser, preserveWS: Boolean) {
   def unparsed(pos: Position, str: String): Tree =
     atPos(pos)( New(_scala_xml_Unparsed, LL(const(str))) )
 
-  def element(pos: Position, qname: String, attrMap: Map[String, Tree], args: Seq[Tree]): Tree = {
+  def element(pos: Position, qname: String, attrMap: mutable.Map[String, Tree], args: Seq[Tree]): Tree = {
     def handleNamespaceBinding(pre: String, z: String): Tree = {
       def mkAssign(t: Tree): Tree = Assign(
         Ident(_tmpscope),
diff --git a/src/compiler/scala/tools/nsc/backend/ScalaPrimitives.scala b/src/compiler/scala/tools/nsc/backend/ScalaPrimitives.scala
index 2754a7b113..70ab35b13c 100644
--- a/src/compiler/scala/tools/nsc/backend/ScalaPrimitives.scala
+++ b/src/compiler/scala/tools/nsc/backend/ScalaPrimitives.scala
@@ -8,8 +8,7 @@ package scala.tools.nsc
 package backend
 
 import scala.tools.nsc.backend.icode._
-
-import scala.collection.mutable.{Map, HashMap}
+import scala.collection.{ mutable, immutable }
 
 /**
  * Scala primitive operations are represented as methods in Any and
@@ -203,13 +202,11 @@ abstract class ScalaPrimitives {
   final val D2F = 265                          // RunTime.d2f(x)
   final val D2D = 266                          // RunTime.d2d(x)
 
-
-  private var primitives: Map[Symbol, Int] = _
+  private val primitives: mutable.Map[Symbol, Int] = new mutable.HashMap()
 
   /** Initialize the primitive map */
   def init {
-    primitives = new HashMap()
-
+    primitives.clear()
     // scala.Any
     addPrimitive(Any_==, EQ)
     addPrimitive(Any_!=, NE)
diff --git a/src/compiler/scala/tools/nsc/backend/WorklistAlgorithm.scala b/src/compiler/scala/tools/nsc/backend/WorklistAlgorithm.scala
index cc2c2b3517..93c37cd5df 100644
--- a/src/compiler/scala/tools/nsc/backend/WorklistAlgorithm.scala
+++ b/src/compiler/scala/tools/nsc/backend/WorklistAlgorithm.scala
@@ -8,7 +8,7 @@ package scala.tools.nsc
 package backend
 
 import scala.tools.nsc.ast._
-import scala.collection.mutable.Stack
+import scala.collection.{ mutable, immutable }
 
 /**
  * Simple implementation of a worklist algorithm. A processing
@@ -26,7 +26,7 @@ import scala.collection.mutable.Stack
  */
 trait WorklistAlgorithm {
   type Elem
-  type WList = Stack[Elem]
+  type WList = mutable.Stack[Elem]
 
   val worklist: WList
 
diff --git a/src/compiler/scala/tools/nsc/backend/icode/Members.scala b/src/compiler/scala/tools/nsc/backend/icode/Members.scala
index 6392131e58..fccab4a44c 100644
--- a/src/compiler/scala/tools/nsc/backend/icode/Members.scala
+++ b/src/compiler/scala/tools/nsc/backend/icode/Members.scala
@@ -9,7 +9,6 @@ package backend
 package icode
 
 import java.io.PrintWriter
-
 import scala.collection.{ mutable, immutable }
 import mutable.{ HashMap, ListBuffer }
 import symtab.Flags.{ DEFERRED }
@@ -219,8 +218,7 @@ trait Members { self: ICodes =>
      * This method should be most effective after heavy inlining.
      */
     def normalize: Unit = if (this.code ne null) {
-      import scala.collection.mutable.{Map, HashMap}
-      val nextBlock: Map[BasicBlock, BasicBlock] = HashMap.empty
+      val nextBlock: mutable.Map[BasicBlock, BasicBlock] = mutable.HashMap.empty
       for (b <- code.blocks.toList
         if b.successors.length == 1;
         val succ = b.successors.head;
diff --git a/src/compiler/scala/tools/nsc/backend/icode/analysis/DataFlowAnalysis.scala b/src/compiler/scala/tools/nsc/backend/icode/analysis/DataFlowAnalysis.scala
index dd9341ac91..c45983d5b6 100644
--- a/src/compiler/scala/tools/nsc/backend/icode/analysis/DataFlowAnalysis.scala
+++ b/src/compiler/scala/tools/nsc/backend/icode/analysis/DataFlowAnalysis.scala
@@ -7,7 +7,7 @@
 package scala.tools.nsc
 package backend.icode.analysis
 
-import scala.collection.mutable.{Map, HashMap, Set, HashSet, LinkedHashSet}
+import scala.collection.{ mutable, immutable }
 
 /** A generic framework for data flow analysis.
  */
@@ -16,11 +16,10 @@ trait DataFlowAnalysis[L <: SemiLattice] {
   type P <: ProgramPoint[P]
   val  lattice: L
 
-  val worklist: Set[P] = new LinkedHashSet
-
-  val in:  Map[P, lattice.Elem] = new HashMap
-  val out: Map[P, lattice.Elem] = new HashMap
-  val visited: HashSet[P] = new HashSet
+  val worklist: mutable.Set[P]          = new mutable.LinkedHashSet
+  val in:  mutable.Map[P, lattice.Elem] = new mutable.HashMap
+  val out: mutable.Map[P, lattice.Elem] = new mutable.HashMap
+  val visited: mutable.HashSet[P]       = new mutable.HashSet
 
   /** collect statistics? */
   var stat = true
diff --git a/src/compiler/scala/tools/nsc/backend/icode/analysis/Liveness.scala b/src/compiler/scala/tools/nsc/backend/icode/analysis/Liveness.scala
index 0e76044977..a211860754 100644
--- a/src/compiler/scala/tools/nsc/backend/icode/analysis/Liveness.scala
+++ b/src/compiler/scala/tools/nsc/backend/icode/analysis/Liveness.scala
@@ -9,7 +9,7 @@ package backend.icode
 package analysis
 
 import scala.collection.{ mutable, immutable }
-import scala.collection.immutable.{ Set, ListSet }
+import immutable.ListSet
 
 /**
  * Compute liveness information for local variables.
diff --git a/src/compiler/scala/tools/nsc/doc/html/page/Template.scala b/src/compiler/scala/tools/nsc/doc/html/page/Template.scala
index 9132d8754d..b6819e7a33 100644
--- a/src/compiler/scala/tools/nsc/doc/html/page/Template.scala
+++ b/src/compiler/scala/tools/nsc/doc/html/page/Template.scala
@@ -9,9 +9,7 @@ package html
 package page
 
 import model._
-
-import scala.xml.{NodeSeq, Text}
-import scala.collection.mutable.HashSet
+import scala.xml.{ NodeSeq, Text }
 
 class Template(tpl: DocTemplateEntity) extends HtmlPage {
 
diff --git a/src/compiler/scala/tools/nsc/interpreter/ReflectionCompletion.scala b/src/compiler/scala/tools/nsc/interpreter/ReflectionCompletion.scala
index 70f1ffa5a7..440f2933f9 100644
--- a/src/compiler/scala/tools/nsc/interpreter/ReflectionCompletion.scala
+++ b/src/compiler/scala/tools/nsc/interpreter/ReflectionCompletion.scala
@@ -9,8 +9,6 @@ package interpreter
 import java.lang.reflect
 import reflect.{ Modifier, AccessibleObject }
 import Modifier.{ isPrivate, isProtected, isStatic }
-import scala.reflect.NameTransformer
-import scala.collection.mutable.HashMap
 import ReflectionCompletion._
 
 trait ReflectionCompletion extends CompletionAware {
diff --git a/src/compiler/scala/tools/nsc/interpreter/XMLCompletion.scala b/src/compiler/scala/tools/nsc/interpreter/XMLCompletion.scala
index f2af57cc36..583e0adc58 100644
--- a/src/compiler/scala/tools/nsc/interpreter/XMLCompletion.scala
+++ b/src/compiler/scala/tools/nsc/interpreter/XMLCompletion.scala
@@ -8,10 +8,10 @@ package interpreter
 
 import xml.{ XML, Group, Node, NodeSeq }
 import XMLCompletion._
-import scala.collection.mutable.HashMap
+import scala.collection.{ mutable, immutable }
 
 class XMLCompletion(root: Node) extends CompletionAware {
-  private val nodeCache = new HashMap[String, Node]
+  private val nodeCache = new mutable.HashMap[String, Node]
   private def getNode(s: String): Option[Node] = {
     completions // make sure cache is populated
     nodeCache get s
diff --git a/src/compiler/scala/tools/nsc/matching/ParallelMatching.scala b/src/compiler/scala/tools/nsc/matching/ParallelMatching.scala
index e20fdd7516..6d0100d705 100644
--- a/src/compiler/scala/tools/nsc/matching/ParallelMatching.scala
+++ b/src/compiler/scala/tools/nsc/matching/ParallelMatching.scala
@@ -7,10 +7,11 @@
 package scala.tools.nsc
 package matching
 
+import PartialFunction._
+import scala.collection.{ mutable, immutable }
 import util.Position
 import transform.ExplicitOuter
 import symtab.Flags
-import collection._
 import mutable.ListBuffer
 import immutable.IntMap
 import annotation.elidable
@@ -28,7 +29,6 @@ trait ParallelMatching extends ast.TreeDSL
   import CODE._
   import Types._
   import Debug._
-  import PartialFunction._
 
   /** Transition **/
   def toPats(xs: List[Tree]): List[Pattern] = xs map Pattern.apply
diff --git a/src/compiler/scala/tools/nsc/util/ClassPath.scala b/src/compiler/scala/tools/nsc/util/ClassPath.scala
index 4994542fdb..830fb9538e 100644
--- a/src/compiler/scala/tools/nsc/util/ClassPath.scala
+++ b/src/compiler/scala/tools/nsc/util/ClassPath.scala
@@ -7,10 +7,9 @@
 package scala.tools.nsc
 package util
 
-import java.io.{ File => JFile }
 import java.net.URL
-
-import scala.collection.mutable.{ListBuffer, ArrayBuffer, HashSet => MutHashSet}
+import scala.collection.{ mutable, immutable }
+import mutable.ListBuffer
 import io.{ File, Directory, Path, AbstractFile }
 import scala.tools.util.StringOps.splitWhere
 import Path.isJarOrZip
diff --git a/src/library/scala/collection/IterableLike.scala b/src/library/scala/collection/IterableLike.scala
index 00c2275ab5..70009391a2 100644
--- a/src/library/scala/collection/IterableLike.scala
+++ b/src/library/scala/collection/IterableLike.scala
@@ -6,10 +6,10 @@
 **                          |/                                          **
 \*                                                                      */
 
-
 package scala.collection
+
 import generic._
-import immutable.{List, Stream}
+import immutable.{ List, Stream }
 import annotation.unchecked.uncheckedVariance
 
 /** A template trait for iterable collections of type `Iterable[A]`.
diff --git a/src/library/scala/collection/IterableViewLike.scala b/src/library/scala/collection/IterableViewLike.scala
index a7578e9a01..a580fd7097 100644
--- a/src/library/scala/collection/IterableViewLike.scala
+++ b/src/library/scala/collection/IterableViewLike.scala
@@ -6,12 +6,9 @@
 **                          |/                                          **
 \*                                                                      */
 
-
-
 package scala.collection
 
 import generic._
-import collection.immutable.Stream
 import TraversableView.NoBuilder
 
 /** A template trait for non-strict views of iterable collections.
diff --git a/src/library/scala/collection/LinearSeqLike.scala b/src/library/scala/collection/LinearSeqLike.scala
index 8bf45348db..397e4131c7 100644
--- a/src/library/scala/collection/LinearSeqLike.scala
+++ b/src/library/scala/collection/LinearSeqLike.scala
@@ -7,10 +7,9 @@
 \*                                                                      */
 
 
-
 package scala.collection
-import generic._
 
+import generic._
 import mutable.ListBuffer
 import immutable.List
 import scala.util.control.Breaks._
diff --git a/src/library/scala/collection/generic/TraversableForwarder.scala b/src/library/scala/collection/generic/TraversableForwarder.scala
index 3995a5258b..ef42a7dcc0 100644
--- a/src/library/scala/collection/generic/TraversableForwarder.scala
+++ b/src/library/scala/collection/generic/TraversableForwarder.scala
@@ -6,14 +6,11 @@
 **                          |/                                          **
 \*                                                                      */
 
-
-
 package scala.collection.generic
-import scala.collection._
 
-import mutable.{Buffer, StringBuilder}
-import immutable.{List, Stream}
-// import immutable.{List, Nil, ::, Stream}
+import scala.collection._
+import mutable.{ Buffer, StringBuilder }
+import immutable.{ List, Stream }
 
 /** <p>
  *    This trait implements a forwarder for traversable objects. It forwards
diff --git a/src/library/scala/collection/mutable/LazyBuilder.scala b/src/library/scala/collection/mutable/LazyBuilder.scala
index db6ca19f2b..aef47801c8 100644
--- a/src/library/scala/collection/mutable/LazyBuilder.scala
+++ b/src/library/scala/collection/mutable/LazyBuilder.scala
@@ -6,12 +6,9 @@
 **                          |/                                          **
 \*                                                                      */
 
-
 package scala.collection
 package mutable
 
-import immutable.{List, Nil}
-
 /** A builder that constructs its result lazily. Iterators or iterables to
  *  be added to this builder with `++=` are not evaluated until `result` is called.
  *
diff --git a/src/library/scala/reflect/Tree.scala b/src/library/scala/reflect/Tree.scala
index ff7fc73c8a..7917d27166 100644
--- a/src/library/scala/reflect/Tree.scala
+++ b/src/library/scala/reflect/Tree.scala
@@ -7,11 +7,8 @@
 \*                                                                      */
 
 
-
 package scala.reflect
 
-import collection.immutable.{List, Nil}
-
 /** This type is required by the compiler and <b>should not be used in client code</b>. */
 abstract class Tree
 
diff --git a/src/library/scala/util/automata/BaseBerrySethi.scala b/src/library/scala/util/automata/BaseBerrySethi.scala
index 63eb0aba9f..4e7c7c4f02 100644
--- a/src/library/scala/util/automata/BaseBerrySethi.scala
+++ b/src/library/scala/util/automata/BaseBerrySethi.scala
@@ -10,12 +10,8 @@
 
 package scala.util.automata
 
-
 import scala.util.regexp.{ Base }
-
 import scala.collection.{ mutable, immutable }
-import mutable.{ HashMap }
-import immutable.{ Set }
 
 // todo: replace global variable pos with acc
 
@@ -30,7 +26,7 @@ abstract class BaseBerrySethi {
   protected var pos = 0
 
   // results which hold all info for the NondetWordAutomaton
-  protected var follow: HashMap[Int, Set[Int]] = _
+  protected var follow: mutable.HashMap[Int, Set[Int]] = _
 
   protected var finalTag: Int = _
 
diff --git a/src/library/scala/util/automata/DetWordAutom.scala b/src/library/scala/util/automata/DetWordAutom.scala
index e1e19589c2..0af49e9d40 100644
--- a/src/library/scala/util/automata/DetWordAutom.scala
+++ b/src/library/scala/util/automata/DetWordAutom.scala
@@ -6,12 +6,9 @@
 **                          |/                                          **
 \*                                                                      */
 
-
-
 package scala.util.automata
 
-
-import scala.collection.{Set, Map}
+import scala.collection.{ mutable, immutable }
 
 /** A deterministic automaton. States are integers, where
  *  0 is always the only initial state. Transitions are represented
@@ -24,21 +21,14 @@ import scala.collection.{Set, Map}
  *  @version 1.0
  */
 abstract class DetWordAutom[T <: AnyRef] {
-
   val nstates: Int
   val finals: Array[Int]
-  val delta: Array[Map[T,Int]]
+  val delta: Array[mutable.Map[T, Int]]
   val default: Array[Int]
 
-  def isFinal(q: Int) = finals(q) != 0
-  def isSink(q: Int) = delta(q).isEmpty && default(q) == q
-
-  def next(q: Int, label: T) = {
-    delta(q).get(label) match {
-      case Some(p) => p
-      case _       => default(q)
-    }
-  }
+  def isFinal(q: Int)        = finals(q) != 0
+  def isSink(q: Int)         = delta(q).isEmpty && default(q) == q
+  def next(q: Int, label: T) = delta(q).getOrElse(label, default(q))
 
   override def toString() = {
     val sb = new StringBuilder("[DetWordAutom  nstates=")
diff --git a/src/library/scala/util/automata/NondetWordAutom.scala b/src/library/scala/util/automata/NondetWordAutom.scala
index 4434ed395d..ed3da00832 100644
--- a/src/library/scala/util/automata/NondetWordAutom.scala
+++ b/src/library/scala/util/automata/NondetWordAutom.scala
@@ -7,11 +7,9 @@
 \*                                                                      */
 
 
-
 package scala.util.automata
 
-import scala.collection.{ immutable, mutable, Set, Seq, Map }
-import immutable.{ BitSet }
+import scala.collection.{ immutable, mutable }
 
 /** A nondeterministic automaton. States are integers, where
  *  0 is always the only initial state. Transitions are represented
@@ -20,13 +18,13 @@ import immutable.{ BitSet }
  *  All states are reachable. Accepting states are those for which
  *  the partial function 'finals' is defined.
  */
-abstract class NondetWordAutom[T <: AnyRef]
-{
+abstract class NondetWordAutom[T <: AnyRef] {
+  import immutable.BitSet
+
   val nstates: Int
   val labels: Seq[T]
-
   val finals: Array[Int] // 0 means not final
-  val delta: Array[Map[T, BitSet]]
+  val delta: Array[mutable.Map[T, BitSet]]
   val default: Array[BitSet]
 
   /** returns true if the state is final */
@@ -41,10 +39,10 @@ abstract class NondetWordAutom[T <: AnyRef]
   /** returns true if there are no accepting states */
   final def isEmpty = (0 until nstates) forall (x => !isFinal(x))
 
-  /** returns a bitset with the next states for given state and label */
+  /** returns a BitSet with the next states for given state and label */
   def next(q: Int, a: T): BitSet = delta(q).getOrElse(a, default(q))
 
-  /** returns a bitset with the next states for given state and label */
+  /** returns a BitSet with the next states for given state and label */
   def next(Q: BitSet, a: T): BitSet = next(Q, next(_, a))
   def nextDefault(Q: BitSet): BitSet = next(Q, default)
 
diff --git a/src/library/scala/util/automata/SubsetConstruction.scala b/src/library/scala/util/automata/SubsetConstruction.scala
index d5b1a19083..5b5df33b11 100644
--- a/src/library/scala/util/automata/SubsetConstruction.scala
+++ b/src/library/scala/util/automata/SubsetConstruction.scala
@@ -6,21 +6,21 @@
 **                          |/                                          **
 \*                                                                      */
 
-
 package scala.util.automata
 
+import scala.collection.{ mutable, immutable }
+
 class SubsetConstruction[T <: AnyRef](val nfa: NondetWordAutom[T]) {
   import nfa.labels
-  import collection.{ mutable, Map }
-  import collection.immutable.BitSet
+  import immutable.BitSet
 
   def selectTag(Q: BitSet, finals: Array[Int]) =
     Q map finals filter (_ > 0) min
 
   def determinize: DetWordAutom[T] = {
     // for assigning numbers to bitsets
-    var indexMap    = Map[BitSet, Int]()
-    var invIndexMap = Map[Int, BitSet]()
+    var indexMap    = collection.Map[BitSet, Int]()
+    var invIndexMap = collection.Map[Int, BitSet]()
     var ix = 0
 
     // we compute the dfa with states = bitsets
@@ -29,10 +29,10 @@ class SubsetConstruction[T <: AnyRef](val nfa: NondetWordAutom[T]) {
 
     var states = Set(q0, sink)    // initial set of sets
     val delta    = new mutable.HashMap[BitSet, mutable.HashMap[T, BitSet]]
-    var deftrans = Map(q0 -> sink, sink -> sink)  // initial transitions
-    var finals: Map[BitSet, Int]  = Map()
-
+    var deftrans = mutable.Map(q0 -> sink, sink -> sink)  // initial transitions
+    var finals: mutable.Map[BitSet, Int]  = mutable.Map()
     val rest = new mutable.Stack[BitSet]
+
     rest.push(sink, q0)
 
     def addFinal(q: BitSet) {
@@ -40,8 +40,8 @@ class SubsetConstruction[T <: AnyRef](val nfa: NondetWordAutom[T]) {
         finals = finals.updated(q, selectTag(q, nfa.finals))
     }
     def add(Q: BitSet) {
-      if (!states.contains(Q)) {
-        states = states + Q
+      if (!states(Q)) {
+        states += Q
         rest push Q
         addFinal(Q)
       }
@@ -74,7 +74,7 @@ class SubsetConstruction[T <: AnyRef](val nfa: NondetWordAutom[T]) {
 
     // create DetWordAutom, using indices instead of sets
     val nstatesR = states.size
-    val deltaR = new Array[Map[T,Int]](nstatesR)
+    val deltaR = new Array[mutable.Map[T, Int]](nstatesR)
     val defaultR = new Array[Int](nstatesR)
     val finalsR = new Array[Int](nstatesR)
 
@@ -83,7 +83,7 @@ class SubsetConstruction[T <: AnyRef](val nfa: NondetWordAutom[T]) {
       val trans = delta(Q)
       val transDef = deftrans(Q)
       val qDef = indexMap(transDef)
-      val ntrans = new mutable.HashMap[T,Int]()
+      val ntrans = new mutable.HashMap[T, Int]()
 
       for ((label, value) <- trans) {
         val p = indexMap(value)
diff --git a/src/library/scala/util/automata/WordBerrySethi.scala b/src/library/scala/util/automata/WordBerrySethi.scala
index 4a41cbbf5a..26f48441d8 100644
--- a/src/library/scala/util/automata/WordBerrySethi.scala
+++ b/src/library/scala/util/automata/WordBerrySethi.scala
@@ -10,8 +10,7 @@
 
 package scala.util.automata
 
-import scala.collection.{ immutable, mutable, Map }
-import immutable.{ Set }
+import scala.collection.{ immutable, mutable }
 import mutable.{ HashSet, HashMap }
 import scala.util.regexp.WordExp
 
@@ -25,17 +24,14 @@ import scala.util.regexp.WordExp
 abstract class WordBerrySethi extends BaseBerrySethi {
   override val lang: WordExp
 
-  import lang.{ Alt, Eps, Letter, Meta, RegExp, Sequ, Star }
+  import lang.{ Alt, Eps, Letter, Meta, RegExp, Sequ, Star, _labelT }
 
-  protected var labels: HashSet[lang._labelT] = _
+  protected var labels: HashSet[_labelT]                   = _
   // don't let this fool you, only labelAt is a real, surjective mapping
-  protected var labelAt: immutable.Map[Int, lang._labelT] = _ // new alphabet "gamma"
-
-  protected var deltaq: Array[HashMap[lang._labelT, List[Int]]] = _ // delta
-
-  protected var defaultq: Array[List[Int]] = _ // default transitions
-
-  protected var initials: Set[Int] = _
+  protected var labelAt: Map[Int, _labelT]                 = _ // new alphabet "gamma"
+  protected var deltaq: Array[HashMap[_labelT, List[Int]]] = _ // delta
+  protected var defaultq: Array[List[Int]]                 = _ // default transitions
+  protected var initials: Set[Int]                         = _
 
   /** Computes <code>first(r)</code> where the word regexp <code>r</code>.
    *
@@ -75,13 +71,13 @@ abstract class WordBerrySethi extends BaseBerrySethi {
    */
 
   /** called at the leaves of the regexp */
-  protected def seenLabel(r: RegExp, i: Int, label: lang._labelT) {
+  protected def seenLabel(r: RegExp, i: Int, label: _labelT) {
     labelAt = labelAt.updated(i, label)
     this.labels += label
   }
 
   // overridden in BindingBerrySethi
-  protected def seenLabel(r: RegExp, label: lang._labelT): Int = {
+  protected def seenLabel(r: RegExp, label: _labelT): Int = {
     pos += 1
     seenLabel(r, pos, label)
     pos
@@ -95,7 +91,7 @@ abstract class WordBerrySethi extends BaseBerrySethi {
   }
 
 
-  protected def makeTransition(src: Int, dest: Int, label: lang._labelT) {
+  protected def makeTransition(src: Int, dest: Int, label: _labelT) {
     val q = deltaq(src)
     q.update(label, dest :: q.getOrElse(label, Nil))
   }
@@ -114,11 +110,11 @@ abstract class WordBerrySethi extends BaseBerrySethi {
 
   protected def initializeAutom() {
     finals   = immutable.Map.empty[Int, Int]                    // final states
-    deltaq   = new Array[HashMap[lang._labelT, List[Int]]](pos) // delta
+    deltaq   = new Array[HashMap[_labelT, List[Int]]](pos) // delta
     defaultq = new Array[List[Int]](pos)                        // default transitions
 
     for (j <- 0 until pos) {
-      deltaq(j) = HashMap[lang._labelT, List[Int]]()
+      deltaq(j) = HashMap[_labelT, List[Int]]()
       defaultq(j) = Nil
     }
   }
@@ -129,7 +125,7 @@ abstract class WordBerrySethi extends BaseBerrySethi {
       else makeTransition(j, k, labelAt(k))
     }
 
-  def automatonFrom(pat: RegExp, finalTag: Int): NondetWordAutom[lang._labelT] = {
+  def automatonFrom(pat: RegExp, finalTag: Int): NondetWordAutom[_labelT] = {
     this.finalTag = finalTag
 
     pat match {
@@ -150,14 +146,14 @@ abstract class WordBerrySethi extends BaseBerrySethi {
         val finalsArr   = 0 until pos map (k => finals.getOrElse(k, 0)) toArray  // 0 == not final
         val initialsArr = initials.toArray
 
-        val deltaArr: Array[Map[lang._labelT, immutable.BitSet]] =
+        val deltaArr: Array[mutable.Map[_labelT, immutable.BitSet]] =
           (0 until pos map { x =>
             HashMap(delta1(x).toSeq map { case (k, v) => k -> immutable.BitSet(v: _*) } : _*)
-          }) toArray
+          }).toArray
 
         val defaultArr  = 0 until pos map (k => immutable.BitSet(defaultq(k): _*)) toArray
 
-        new NondetWordAutom[lang._labelT] {
+        new NondetWordAutom[_labelT] {
           val nstates  = pos
           val labels   = WordBerrySethi.this.labels.toList
           val initials = initialsArr