// changes the icon of all error-having modules' frames to a little flash icon
sclass ErrorIcon extends Module {
  void update {
    for (Module m : onModules()) {
      O error = m.getError();
      if (error != null)
        internalFrameIcon(m.vis, #1101276);
    }
  }
}

sclass Errors extends Module {
  L errors = synchroList(new CircularArrayList);
  int errorsToKeep = 10;
  
  void addError(Throwable e) {
    addToListWithMaxSize(errors, e, errorsToKeep);
    change();
  }
}