code: function grammarSyntaxError(matchFailure) {
    var e = new Error();
    Object.defineProperty(e, 'message', {get: function() { return matchFailure.message; }});
    Object.defineProperty(e, 'shortMessage', {get: function() {
      return 'Expected ' + matchFailure.getExpectedText();
    }});
    e.interval = matchFailure.getInterval();
    return e;
  }
docs: ----------------- errors about grammars ----------------- Grammar syntax error