abstract sclass DynPrintLog extends DynModule {
  transient JTextArea ta;
  transient Lock updatePrintLog_lock = lock();
  
  JComponent visualize() {
    ret awtEvery(
      jSection("Log", ta = moveCaretToEnd(typeWriterTextArea(localPrintLog()))),
      500, r updatePrintLog);
  }
  
  void updatePrintLog {
    // TODO: optimize
    lock updatePrintLog_lock;
    if (ta != null) setText(ta, localPrintLog());
  }
  
  JTextArea myPrintLogComponent() { ret ta; }
}