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Author: odersky

compiler/src/dotty/tools/dotc/interactive/InteractiveDriver.scala

@@ -179,6 +179,11 @@ class InteractiveDriver(settings: List[String]) extends Driver {
 
   private val compiler: Compiler = new InteractiveCompiler
 
+  /** Remove attachments and error out completers. The goal is to avoid
+   *  having a completer hanging in a typed tree which can capture the context
+   *  of a previous run. Note that typed trees can have untyped or partially
+   *  typed children if the source contains errors.
+   */
   private def cleanup(tree: tpd.Tree)(implicit ctx: Context): Unit = tree.foreachSubTree { t =>
     if (t.hasType) {
       if (t.symbol.exists) {