standalone document "ready" function

gistfile1

function docReady(callback, bubble) {

    var addListener = this.addEventListener || this.attachEvent,
        removeListener = this.removeEventListener || this.detachEvent

    if (document.readyState === "complete" || document.readyState === "loaded" || document.readyState === "interactive") {
        callback();
        return;
    }

    bubble = bubble || false;
    var eventName = document.addEventListener ? "DOMContentLoaded" : "onreadystatechange";
    addListener.call(document, eventName, function(event) {
        removeListener(eventName, arguments.callee, bubble);
        callback();
    }, bubble);

};