Simple filtering for Google Tags - ES6

gtm.es6.js

const filterClasses = (ev) => {
    // Filter those classes for a class containing with 'gtm-'
    const filteredClasses = ev.toElement.className.split(' ').filter((thisClass) => thisClass.indexOf('gtm-' !== -1) ? thisClass : false);
    //If it was a match, return the matching classname as a string, otherwise, return false.
    if (filteredClasses.length > 0) return filteredClasses[0];
    else return false;
};

const gaSend = (className) =>
    ga('send', {
        hitType: 'event',
        eventCategory: 'Links',
        eventAction: 'click',
        eventLabel: className
    });

//When the doc is ready.
$(document).ready(() =>
    $(document).on('click', 'body a', (ev) =>
        filterClasses(ev) ? gaSend(filterClasses(ev)) : false));