Mootools

gistfile1.js

function jQueryLoaded(){
  return (typeof(jQuery) != 'undefined');
}

if(jQueryLoaded()){
  console.log('WTF jQuery?');

  $('document').ready(function(){
    jquery_link_to();
  });
}
else{
  window.addEvent('domready', function() {
    console.log('WTF MooTools?');
    mootools_link_to();
  });
}