code: public static void debug(JShell state, PrintStream err, Exception ex, String where) {
          if (isDebugEnabled(state, 0xFFFFFFFF)) {
              err.printf("Fatal error: %s: %s\n", where, ex.getMessage());
              ex.printStackTrace(err);
          }
      }
docs: Displays a fatal exception as debug info.
  
  @param state the current JShell instance
  @param err the {@code PrintStream} to report on
  @param ex the fatal Exception
  @param where additional context