JavaScript: Storing data with an object. Equivalent with data()

objData.js

// Found here: http://stackoverflow.com/questions/7783907/equivalent-of-data-for-jquery-objects/7784011#7784011

$.fn.objData = function(key, value) {
    var rootData = $(document).data("jQueryObjectData");
    if (!rootData) {
        $(document).data("jQueryObjectData", rootData = {});
    }
    var objData = rootData[this];
    if (!objData) {
        rootData[this] = objData = {};
    }
    if (typeof value === "undefined") {
        return objData[key];
    }
    objData[key] = value;
    return this;
};