2 files changed, 12 insertions, 10 deletions
diff --git a/compiler/src/dotty/tools/dotc/util/FreshNameCreator.scala b/compiler/src/dotty/tools/dotc/util/FreshNameCreator.scala
index 8892a570e..5dbec3e5a 100644
--- a/compiler/src/dotty/tools/dotc/util/FreshNameCreator.scala
+++ b/compiler/src/dotty/tools/dotc/util/FreshNameCreator.scala
@@ -3,9 +3,12 @@ package dotc
 package util
 
 import scala.collection.mutable
+import core.Names.TermName
+import core.NameKinds.UniqueNameKind
+import core.StdNames.str
 
-trait FreshNameCreator {
-  def newName(prefix: String = ""): String
+abstract class FreshNameCreator {
+  def newName(prefix: TermName, unique: UniqueNameKind): TermName
 }
 
 object FreshNameCreator {
@@ -18,11 +21,11 @@ object FreshNameCreator {
      * that the returned name has never been returned by a previous
      * call to this function (provided the prefix does not end in a digit).
      */
-    def newName(prefix: String): String = {
-      val safePrefix = prefix.replaceAll("""[<>]""", """\$""")
-      counters(safePrefix) += 1
-      val counter = counters(safePrefix)
-      if (prefix.isEmpty) "$" + counter + "$" else safePrefix + counter
+    def newName(prefix: TermName, unique: UniqueNameKind): TermName = {
+      val key = str.sanitize(prefix.toString + unique.separator)
+      counters(key) += 1
+      val counter = counters(key)
+      prefix.derived(unique.NumberedInfo(counter))
     }
   }
 }
diff --git a/compiler/src/dotty/tools/dotc/util/NameTransformer.scala b/compiler/src/dotty/tools/dotc/util/NameTransformer.scala
index 330d513fe..52f8e6ec0 100644
--- a/compiler/src/dotty/tools/dotc/util/NameTransformer.scala
+++ b/compiler/src/dotty/tools/dotc/util/NameTransformer.scala
@@ -60,7 +60,7 @@ object NameTransformer {
    *  @param name the string to encode
    *  @return     the string with all recognized opchars replaced with their encoding
    */
-  def encode[N <: Name](name: N): N = {
+  def encode(name: SimpleTermName): SimpleTermName = {
     var buf: StringBuilder = null
     val len = name.length
     var i = 0
@@ -87,8 +87,7 @@ object NameTransformer {
       i += 1
     }
     if (buf eq null) name
-    else if (name.isTermName) buf.toString.toTermName.asInstanceOf[N]
-    else buf.toString.toTypeName.asInstanceOf[N]
+    else termName(buf.toString)
   }
 
   /** Replace `\$opname` by corresponding operator symbol.