Callback class member

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Hi. Is it possible to use a member class method as a callback? Something like this:

void Node::chatterCallback(const std_msgs::String::ConstPtr& msg){
ROS_INFO("I heard: [%s]", msg->data.c_str());
}

void Node::Subscribe(){
ros::NodeHandle n;
ros::Subscriber sub = n.subscribe("alives", 1000, &Node::chatterCallback, this);
}

At the examples (http://www.ros.org/wiki/roscpp_tutorials/Tutorials/UsingClassMethodsAsCallbacks) , I've seen:

Listener listener;
ros::Subscriber sub = n.subscribe("chatter", 1000, &Listener::callback, &listener);

But I don't want to instantiate another object. I've the callback function as a method in my class.