Queue and (this)

Queue.js

function Queue(delay){
  this._lastExecutionTime = new Date();
  this._delay = delay;
}

Queue.prototype.dequeue = function(){
  //return first function in the list
};


Queue.prototype.execute = function(){
		var lastExec = this._lastExecutionTime;
		var currentExec = new Date();
		var executionDiff = currentExec - lastExec;
		if (executionDiff < this._delay){
			setTimeout(this.execute, executionDiff);
			//is setTimeout where "this" becomes window?
		} else {
			this.dequeue()();
			if (this.getTasks.length() !== 0){
				this.execute();
			}
		}
};