JSFiddle - React, Tailwind, and code Playground

JavaScript

(function($){
    var fakeAsync = {};
    function fakeAsyncFunction( ) {
        alert(1);
        $(fakeAsync).trigger('customDone');
    }
    
    function a( ) {
        alert(2);
    }
    function b( ) {
        alert(3);
    }
    function c( ) {
        alert(4);
    }
    
    window.setTimeout(fakeAsyncFunction, 1000);
    
    $(fakeAsync).on('customDone', a)
        .on('customDone', b)
        .on('customDone', c);
})(jQuery);