code: private static void reportError(List messages, String fileName, int lineNr, String line, String errorMessage) {
  		messages.add(new Date() + " ERROR in \"" + fileName + "\" at line " + lineNr + ':');
  		messages.add(errorMessage);
  	}
docs: Adds a message to the list.
  
  @param fileName
  @param lineNr
  @param line
  @param errorMessage