quick DOM helper

gistfile1.js

const $ = (selector) => {
    const helper = {
        version: '0.0.1'
    };
    helper._elms = document.querySelectorAll(selector);
    gf
    const processArray = cb => helper._elms.forEach(cb);

    helper.on = (event, callback) => {
        processArray(elm => elm.addEventListener(event, callback));
    };

    helper.addClass = (cssClass) => {
        processArray(elm => elm.classList.add(cssClass));
    };

    helper.removeClass = (cssClass) => {
        processArray(elm => elm.classList.remove(cssClass));
    };

    helper.toggleClass = (cssClass) => {
        processArray(elm => elm.classList.toggle(cssClass));
    };

    return helper;
};