var events = require('events');

var eventEmitter = new events.EventEmitter();

​

//Create an event handler:

var myEventHandler = function () {

  console.log('I hear a scream!');

}

​

//Assign the eventhandler to an event:

eventEmitter.on('scream', myEventHandler);

​

//Fire the 'scream' event:

eventEmitter.emit('scream');

​