anchor.diff:    return Future.wait(cleanupFutures);
   }
   
  +void debuggerError(self, parent, zone, error, StackTrace trace) {
  +  print('\n--------\nExiting due to unexpected error:\n'
  +        '  $error\n$trace\n');
  +  debuggerQuit();
  +}
  +
   Future debuggerQuit() {
     // Kill target process, if any.
     if (targetProcess != null) {
  
positive.code:   }
    if (event == "paused") {
      cmdo.hide();
      handlePausedEvent(msg);
      cmdo.show();
      return;
    }
    if (event == "breakpointResolved") {
  
negative.code: 
  import "ddbg/lib/commando.dart";
  
  class TargetScript {
    // The text of a script.
    String source = null;
  
    // A mapping from line number to source text.
    List<String> lineToSource = null;
  
    // A mapping from token offset to line number.
    Map<int,int> tokenToLine = null;
  }
  
  
  class TargetIsolate {
    int id;
    // The location of the last paused event.
  