Login bookmarklet for a Prototype site

prototype_login.js

javascript:(function() {
  var usr = '000000', pwd = '000000', cde = '000000';
  var card;
  if (card = $('cardPwd')) {
    card.value = cde;
  } else {
    $('userId').value = usr;
    $('fixedPwd').value = pwd;
  }
  $('loginForm').submit();
})();