selector.js

// dollar selector
function $(C, P) {
    P = P || document;
    return /:first$/.test(C) ? (P = P.querySelector(C.slice(0, -6))) ? [P] : [] : [].slice.call(P.querySelectorAll(C))
}

// simple utility to add an event listener
$.on = function (CSS, parentNode, type, handler, capture) {
    // in case parentNode is missing
    if (typeof type !== 'string') {
        capture = handler;
        handler = type;
        type = parentNode;
        parentNode = null;
    }
    return $(CSS, parentNode).map(function (el) {
        el.addEventListener(type, handler, capture);
        return el;
    });
};

// example
$.on('a', 'click', function (e) {
    // prevent default
    e.preventDefault();
    // and show the link
    alert(e.currentTarget.href);
});