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 var addClass, hasClass, removeClass;
 
 Y.mix(Y.DOM, {
 /**
 * Determines whether a DOM element has the given className.
 * @method hasClass
 * @for DOM
 * @param {HTMLElement} element The DOM element.
 * @param {String} className the class name to search for
 * @return {Boolean} Whether or not the element has the given class.
 */
 hasClass: function(node, className) {
 var re = Y.DOM._getRegExp('(?:^|\\s+)' + className + '(?:\\s+|$)');
 return re.test(node.className);
 },
 
 /**
 * Adds a class name to a given DOM element.
 * @method addClass
 * @for DOM
 * @param {HTMLElement} element The DOM element.
 * @param {String} className the class name to add to the class attribute
 */
 addClass: function(node, className) {
 if (!Y.DOM.hasClass(node, className)) { // skip if already present
 node.className = Y.Lang.trim([node.className, className].join(' '));
 }
 },
 
 /**
 * Removes a class name from a given element.
 * @method removeClass
 * @for DOM
 * @param {HTMLElement} element The DOM element.
 * @param {String} className the class name to remove from the class attribute
 */
 removeClass: function(node, className) {
 if (className && hasClass(node, className)) {
 node.className = Y.Lang.trim(node.className.replace(Y.DOM._getRegExp('(?:^|\\s+)' +
 className + '(?:\\s+|$)'), ' '));
 
 if ( hasClass(node, className) ) { // in case of multiple adjacent
 removeClass(node, className);
 }
 }
 },
 
 /**
 * Replace a class with another class for a given element.
 * If no oldClassName is present, the newClassName is simply added.
 * @method replaceClass
 * @for DOM
 * @param {HTMLElement} element The DOM element
 * @param {String} oldClassName the class name to be replaced
 * @param {String} newClassName the class name that will be replacing the old class name
 */
 replaceClass: function(node, oldC, newC) {
 //Y.log('replaceClass replacing ' + oldC + ' with ' + newC, 'info', 'Node');
 removeClass(node, oldC); // remove first in case oldC === newC
 addClass(node, newC);
 },
 
 /**
 * If the className exists on the node it is removed, if it doesn't exist it is added.
 * @method toggleClass
 * @for DOM
 * @param {HTMLElement} element The DOM element
 * @param {String} className the class name to be toggled
 * @param {Boolean} addClass optional boolean to indicate whether class
 * should be added or removed regardless of current state
 */
 toggleClass: function(node, className, force) {
 var add = (force !== undefined) ? force :
 !(hasClass(node, className));
 
 if (add) {
 addClass(node, className);
 } else {
 removeClass(node, className);
 }
 }
 });
 
 hasClass = Y.DOM.hasClass;
 removeClass = Y.DOM.removeClass;
 addClass = Y.DOM.addClass;