There was a fascinating tangle of name creation...

There was a fascinating tangle of name creation functions passing around
positions only to reach the end of the line and discard the position
since names don't have positions. I deleted all of it. The winner for
most creative use of parameters was the freshName function in etaExpand,
with this signature:

  def freshName(pos: util.Position, n: Int)

And an implementation referencing neither pos nor n. "In a world beset
by attrition on all sides... a people defeated by entropy... one man
will show them the power of deletion." No review.

11 files changed, 26 insertions, 66 deletions

diff --git a/src/compiler/scala/tools/nsc/CompilationUnits.scala b/src/compiler/scala/tools/nsc/CompilationUnits.scala
index de48ff9931..564e4f2705 100644
--- a/src/compiler/scala/tools/nsc/CompilationUnits.scala
+++ b/src/compiler/scala/tools/nsc/CompilationUnits.scala
@@ -16,7 +16,7 @@ trait CompilationUnits { self: Global =>
   class CompilationUnit(val source: SourceFile) extends CompilationUnitTrait {
 
     /** the fresh name creator */
-    var fresh : FreshNameCreator = new FreshNameCreator.Default
+    var fresh: FreshNameCreator = new FreshNameCreator.Default
 
     /** the content of the compilation unit in tree form */
     var body: Tree = EmptyTree
diff --git a/src/compiler/scala/tools/nsc/ast/Trees.scala b/src/compiler/scala/tools/nsc/ast/Trees.scala
index 4fcfde3beb..17a932575b 100644
--- a/src/compiler/scala/tools/nsc/ast/Trees.scala
+++ b/src/compiler/scala/tools/nsc/ast/Trees.scala
@@ -9,7 +9,7 @@ package ast
 import scala.collection.mutable.ListBuffer
 import scala.tools.nsc.symtab.SymbolTable
 import scala.tools.nsc.symtab.Flags._
-import scala.tools.nsc.util.{FreshNameCreator, HashSet, SourceFile}
+import scala.tools.nsc.util.{ FreshNameCreator, HashSet, SourceFile }
 
 trait Trees extends reflect.generic.Trees { self: SymbolTable =>
 
diff --git a/src/compiler/scala/tools/nsc/ast/parser/Parsers.scala b/src/compiler/scala/tools/nsc/ast/parser/Parsers.scala
index 6f41b3ac47..997573f7f5 100644
--- a/src/compiler/scala/tools/nsc/ast/parser/Parsers.scala
+++ b/src/compiler/scala/tools/nsc/ast/parser/Parsers.scala
@@ -73,12 +73,10 @@ self =>
     val in = new UnitScanner(unit, patches)
     in.init()
 
-    def freshName(pos: Position, prefix: String): Name =
-      unit.fresh.newName(pos, prefix)
+    def freshName(prefix: String): Name = unit.fresh.newName(prefix)
 
     def o2p(offset: Int): Position = new OffsetPosition(unit.source,offset)
     def r2p(start: Int, mid: Int, end: Int): Position = rangePos(unit.source, start, mid, end)
-
     def warning(offset: Int, msg: String) { unit.warning(o2p(offset), msg) }
 
     def deprecationWarning(offset: Int,
@@ -150,18 +148,12 @@ self =>
 
   abstract class Parser {
     val in: Scanner
-    //val unit : CompilationUnit
-    //import in.ScanPosition
-    def freshName(pos: Position, prefix: String): Name
-    def freshName(prefix: String): Name = freshName(NoPosition, prefix) // todo get rid of position
 
+    def freshName(prefix: String): Name
     def o2p(offset: Int): Position
     def r2p(start: Int, mid: Int, end: Int): Position
-    //private implicit def p2i(pos: Position) = pos.offset.get
 
     /** whether a non-continuable syntax error has been seen */
-    //private var syntaxErrorSeen = false
-
     private var lastErrorOffset : Int = -1
 
     object treeBuilder extends TreeBuilder {
@@ -1002,7 +994,7 @@ self =>
     /** WildcardType ::= `_' TypeBounds
      */
     def wildcardType(start: Int) = {
-      val pname = freshName(o2p(start), "_$").toTypeName
+      val pname = freshName("_$").toTypeName
       val t = atPos(start) { Ident(pname) }
       val bounds = typeBounds()
       val param = atPos(t.pos union bounds.pos) { makeSyntheticTypeParam(pname, bounds) }
@@ -1141,7 +1133,7 @@ self =>
       case WHILE =>
         val start = in.offset
         atPos(in.skipToken()) {
-          val lname: Name = freshName(o2p(start), nme.WHILE_PREFIX)
+          val lname: Name = freshName(nme.WHILE_PREFIX)
           val cond = condExpr()
           newLinesOpt()
           val body = expr()
@@ -1150,7 +1142,7 @@ self =>
       case DO =>
         val start = in.offset
         atPos(in.skipToken()) {
-          val lname: Name = freshName(o2p(start), nme.DO_WHILE_PREFIX)
+          val lname: Name = freshName(nme.DO_WHILE_PREFIX)
           val body = expr()
           if (isStatSep) in.nextToken()
           accept(WHILE)
@@ -1325,7 +1317,7 @@ self =>
           path(true, false)
         case USCORE =>
           val start = in.offset
-          val pname = freshName(o2p(start), "x$")
+          val pname = freshName("x$")
           in.nextToken()
           val id = atPos(start) (Ident(pname))
           val param = atPos(id.pos.focus){ makeSyntheticParam(pname) }
diff --git a/src/compiler/scala/tools/nsc/backend/opt/ClosureElimination.scala b/src/compiler/scala/tools/nsc/backend/opt/ClosureElimination.scala
index ba7e00901a..d5bb6e0f88 100644
--- a/src/compiler/scala/tools/nsc/backend/opt/ClosureElimination.scala
+++ b/src/compiler/scala/tools/nsc/backend/opt/ClosureElimination.scala
@@ -88,16 +88,6 @@ abstract class ClosureElimination extends SubComponent {
    *
    */
   class ClosureElim {
-
-    /* fresh name counter */
-    var count = 0
-
-    def freshName(s: String) = {
-      val ret = s + this.count
-      this.count += 1
-      ret
-    }
-
     def analyzeClass(cls: IClass): Unit = if (settings.Xcloselim.value) {
       cls.methods.foreach { m =>
         analyzeMethod(m)
@@ -107,7 +97,6 @@ abstract class ClosureElimination extends SubComponent {
 
     val cpp = new copyPropagation.CopyAnalysis
 
-
     import copyPropagation._
 
     /* Some embryonic copy propagation. */
diff --git a/src/compiler/scala/tools/nsc/javac/JavaParsers.scala b/src/compiler/scala/tools/nsc/javac/JavaParsers.scala
index 3c9cdbf878..8c0e5585be 100644
--- a/src/compiler/scala/tools/nsc/javac/JavaParsers.scala
+++ b/src/compiler/scala/tools/nsc/javac/JavaParsers.scala
@@ -22,7 +22,7 @@ trait JavaParsers extends JavaScanners {
 
   class JavaUnitParser(val unit: global.CompilationUnit) extends JavaParser {
     val in = new JavaUnitScanner(unit)
-    def freshName(pos : Position, prefix : String) = unit.fresh.newName(pos, prefix)
+    def freshName(prefix : String) = unit.fresh.newName(prefix)
     implicit def i2p(offset : Int) : Position = new OffsetPosition(unit.source, offset)
     def warning(pos : Int, msg : String) : Unit = unit.warning(pos, msg)
     def syntaxError(pos: Int, msg: String) : Unit = unit.error(pos, msg)
@@ -32,7 +32,7 @@ trait JavaParsers extends JavaScanners {
 
     val in: JavaScanner
     protected def posToReport: Int = in.currentPos
-    protected def freshName(pos : Position, prefix : String): Name
+    protected def freshName(prefix : String): Name
     protected implicit def i2p(offset : Int) : Position
     private implicit def p2i(pos : Position): Int = if (pos.isDefined) pos.point else -1
 
diff --git a/src/compiler/scala/tools/nsc/matching/Matrix.scala b/src/compiler/scala/tools/nsc/matching/Matrix.scala
index fa3e7371a7..f7f7b2cc41 100644
--- a/src/compiler/scala/tools/nsc/matching/Matrix.scala
+++ b/src/compiler/scala/tools/nsc/matching/Matrix.scala
@@ -194,7 +194,7 @@ trait Matrix extends MatrixAdditions {
       override def toString() = "%s: %s = %s".format(lhs, lhs.info, rhs)
     }
 
-    def newName(pos: Position, s: String) = cunit.fresh.newName(pos, s)
+    def newName(s: String) = cunit.fresh.newName(s)
 
     /** Sets the rhs to EmptyTree, which makes the valDef ignored in Scrutinee.
      */
@@ -211,7 +211,7 @@ trait Matrix extends MatrixAdditions {
       label: String = "temp"): PatternVar =
     {
       val tpe   = ifNull(_tpe, root.tpe)
-      val name  = newName(root.pos, label)
+      val name  = newName(label)
       val sym   = newVar(root.pos, tpe, flags(checked), name)
 
       tracing("copy", new PatternVar(sym, root, checked))
@@ -233,7 +233,7 @@ trait Matrix extends MatrixAdditions {
       flags: List[Long] = Nil,
       name: Name = null): Symbol =
     {
-      val n: Name = if (name == null) newName(pos, "temp") else name
+      val n: Name = if (name == null) newName("temp") else name
       // careful: pos has special meaning
       owner.newVariable(pos, n) setInfo tpe setFlag (SYNTHETIC.toLong /: flags)(_|_)
     }
diff --git a/src/compiler/scala/tools/nsc/matching/ParallelMatching.scala b/src/compiler/scala/tools/nsc/matching/ParallelMatching.scala
index 61a8b81820..b82298f2de 100644
--- a/src/compiler/scala/tools/nsc/matching/ParallelMatching.scala
+++ b/src/compiler/scala/tools/nsc/matching/ParallelMatching.scala
@@ -544,7 +544,7 @@ trait ParallelMatching extends ast.TreeDSL
         }
 
       lazy val label =
-        owner.newLabel(scrut.pos, newName(scrut.pos, "failCont%")) setInfo MethodType(Nil, labelBody.tpe)
+        owner.newLabel(scrut.pos, newName("failCont%")) setInfo MethodType(Nil, labelBody.tpe)
 
       lazy val cond =
         handleOuter(rhs MEMBER_== scrut.id )
diff --git a/src/compiler/scala/tools/nsc/symtab/Symbols.scala b/src/compiler/scala/tools/nsc/symtab/Symbols.scala
index 083b6667bf..567754dc2e 100644
--- a/src/compiler/scala/tools/nsc/symtab/Symbols.scala
+++ b/src/compiler/scala/tools/nsc/symtab/Symbols.scala
@@ -217,6 +217,7 @@ trait Symbols extends reflect.generic.Symbols { self: SymbolTable =>
       sym setFlag (STABLE | SYNTHETIC)
       if (isTrait) sym setFlag DEFERRED
       sym.expandName(this)
+      // todo: stop depending on compiler bug (ticket #3871) to set referenced.
       sym.referenced = this
       sym
     }
diff --git a/src/compiler/scala/tools/nsc/symtab/Types.scala b/src/compiler/scala/tools/nsc/symtab/Types.scala
index d4063746a2..abe9569346 100644
--- a/src/compiler/scala/tools/nsc/symtab/Types.scala
+++ b/src/compiler/scala/tools/nsc/symtab/Types.scala
@@ -5194,7 +5194,7 @@ A type's typeSymbol should never be inspected directly.
 
   /** The greatest lower bound wrt <:< of a list of types */
   private def glb(ts: List[Type], depth: Int): Type = {
-    def glb0(ts0: List[Type]): Type = elimSuper(ts0 map (_.deconst)) match {// todo: deconst needed?
+    def glb0(ts0: List[Type]): Type = elimSuper(ts0) match {
       case List() => AnyClass.tpe
       case List(t) => t
       case ts @ PolyType(tparams, _) :: _ =>
diff --git a/src/compiler/scala/tools/nsc/typechecker/EtaExpansion.scala b/src/compiler/scala/tools/nsc/typechecker/EtaExpansion.scala
index 7cfc4733d3..c24d5c0505 100644
--- a/src/compiler/scala/tools/nsc/typechecker/EtaExpansion.scala
+++ b/src/compiler/scala/tools/nsc/typechecker/EtaExpansion.scala
@@ -49,20 +49,11 @@ trait EtaExpansion { self: Analyzer =>
    */
   def etaExpand(unit : CompilationUnit, tree: Tree): Tree = {
     val tpe = tree.tpe
-    val symbolHash = ""
     var cnt = 0 // for NoPosition
-    def freshName(pos : util.Position, n : Int) = {
+    def freshName() = {
       cnt += 1
-      newTermName(unit.fresh.newName(pos, "eta$" + (cnt - 1) + "$"))
-      // Note - the comment below made more sense before I ripped inIDE out -
-      // I leave it in to give context to the todo: at the bottom.
-      // Martin to Sean: I removed the
-      // else if (n == 0) branch and changed `n' in the line above to `(cnt - 1)'
-      // this was necessary because otherwise curried eta-expansions would get the same
-      // symbol. An example which fails test/files/run/Course-2002-02.scala
-      // todo: review and get rid of the `n' argument (which is unused right now).
+      newTermName(unit.fresh.newName("eta$" + (cnt - 1) + "$"))
     }
-    // { cnt = cnt + 1; newTermName("eta$" + cnt) }
     val defs = new ListBuffer[Tree]
 
     /** Append to <code>defs</code> value definitions for all non-stable
@@ -75,7 +66,7 @@ trait EtaExpansion { self: Analyzer =>
       def liftout(tree: Tree): Tree =
         if (treeInfo.isPureExpr(tree)) tree
         else {
-          val vname: Name = freshName(tree.pos, 0)
+          val vname: Name = freshName()
           // Problem with ticket #2351 here
           defs += atPos(tree.pos) {
             ValDef(Modifiers(SYNTHETIC), vname, TypeTree(), tree)
@@ -107,10 +98,6 @@ trait EtaExpansion { self: Analyzer =>
     }
 
     /** Eta-expand lifted tree.
-     *
-     *  @param tree ...
-     *  @param tpe  ...
-     *  @return     ...
      */
     def expand(tree: Tree, tpe: Type): Tree = tpe match {
       case mt @ MethodType(paramSyms, restpe) if !mt.isImplicit =>
diff --git a/src/compiler/scala/tools/nsc/util/FreshNameCreator.scala b/src/compiler/scala/tools/nsc/util/FreshNameCreator.scala
index 714e731891..cf6994da51 100644
--- a/src/compiler/scala/tools/nsc/util/FreshNameCreator.scala
+++ b/src/compiler/scala/tools/nsc/util/FreshNameCreator.scala
@@ -9,25 +9,20 @@ package util
 import scala.collection.mutable.HashMap
 
 trait FreshNameCreator {
-
-  /** do not call before after type checking ends.
+  /** Do not call before after type checking ends.
+   *  PP: I think that directive needs to lose a word somewhere.
    */
-  @deprecated("use newName(Position, String) instead")
-  def newName(prefix: String): String
-
-  /** do not call before after type checking ends.
-   */
-  @deprecated("use newName(Position) instead")
   def newName(): String
+  def newName(prefix: String): String
 
-  def newName(pos: util.Position, prefix: String): String
-  def newName(pos: util.Position): String
+  @deprecated("use newName(prefix)")
+  def newName(pos: util.Position, prefix: String): String = newName(prefix)
+  @deprecated("use newName()")
+  def newName(pos: util.Position): String = newName()
 }
 
 object FreshNameCreator {
-
   class Default extends FreshNameCreator {
-
     protected var counter = 0
     protected val counters = new HashMap[String, Int]
 
@@ -42,13 +37,9 @@ object FreshNameCreator {
       counters(safePrefix) = count
       safePrefix + count
     }
-    def newName(pos: util.Position, prefix: String) = newName(prefix)
-    def newName(pos: util.Position) = newName()
-
     def newName(): String = {
       counter += 1
       "$" + counter + "$"
     }
   }
-
 }