public function getTagValue($tag)
	{
		if(!$this->hasTag($tag))
		{
			throw new \OutOfBoundsException('Tag ' . $tag . ' is not set');
		}
		
		if(empty($this->tags[$tag]))
		{
			throw new \OutOfBoundsException('Tag ' . $tag . ' does not have a value');
		}
		
		return $this->tags[$tag][0];
	}