Math.guid.js

/**
 * Math.guid
 * from : http://www.broofa.com/2008/09/javascript-uuid-function/
 */
Math.guid = function(){
    return 'xxxxxxxx-xxxx-4xxx-yxxxx-xxxxxxxxxxxx'.replace(/[xy]/g, function(c){
        var r = Math.random() * 16 | 0,
            v = c === 'x' ? r : (r & 0x3 | 0x8);

        return v.toString(16)
    }).toUpperCase();
}