My simple Queue app with adder and executer

queue.js

Queue = function(){
    this.stopped = false;
    this.array = [];
}

Queue.prototype = {
    add: function(fn) { this.array.push(fn) },
    pause: function() { this.stopped = true },
    go: function() { this.stopped = false; this.exec(); },
    exec: function() {
        while(this.array.length>0) {
            if (this.stopped==true) break;
            (this.array.shift())(this);
        }
    }
}

qu = new Queue();
qu.add(function(){alert("One")});
qu.add(function(){alert("Two")});
qu.add(function(){
  qu.pause();
  setTimeout(function(){
    alert("Three");
    qu.go();
  },3000);
});
qu.add(function(){alert("Four")});
qu.add(function(){
  var queue = arguments[0];
  queue.pause();
  setTimeout(function(){
    alert("Five");
    queue.go();
  },3000);
});
qu.add(function(){alert("Six")});
qu.exec();