executeIf.js

(() => {
    const execute = () => {
        jQuery(($) => {
          ///
          // Do something
          ///
        });
    };
    
    const executeIf = (globalProp, execute) => () => {
        if (window[globalProp]) {
            execute();
            console.log('Execute: ', execute)
        } else {
            setTimeout(executeIf(globalProp, execute), 500);
        }        
    };
    
    executeIf('jQuery', execute)();        
})();