Unique Filename generator

nameGenerator.js

define('utils/files/nameGenerator', function() {
    var count = 0; 
    var lastId = 0; 
    this.getName = function(ext) {
        var d = new Date;
        
        var f =  d.getTime();
        if(f == lastId) {
            count++; 
        } else {
            count = 0; 
            
        }
        lastId = f; 
        
        if(count>0) {
            f += '_'+count;
        }
        if(typeof ext != 'undefined') {
            f += '.'+ext;
        }
        return f;
    };
    return this; 
});