JSFiddle - React, Tailwind, and code Playground

HTML

<form id="test">
    <input type="text">
    <input type="submit" value="submit">
</form>

JavaScript

$(function() {
    //create x
    function x() {
        alert('im from x');
    }

    //create y that receives the function
    function y(callback) {

        //bind your handler which calls callback (which was x)
        $('#test').submit(function() {
            callback();
            return false;
        });

    }

    //call y that sends over a reference to x
    y(x);
});