event-emitter-recap.js

var EventEmitter = require('events').EventEmitter
var emitter = new EventEmitter()
var util = require('util')

emitter.on('newListener', newListener)
function newListener() {
  console.log('new listener added')
}

emitter.on('removeListener', removeListener)
function removeListener() {
  console.log('removed listener')
}

emitter.on('connection #1', function() {
  console.log('got connection #1')
}).once('connection #1', function() {
  // get call only once and be removed immediately
  console.log('first connection #1')
})

emitter.on('connection #2', connection2)
emitter.on('connection #3', connection3)

function connection2() {
  console.log('got connection #2')
}

function connection3() {
  console.log('got connection #3')
}

emitter.emit('connection #1')
emitter.emit('connection #1')
emitter.emit('connection #1')
emitter.emit('connection #2')
emitter.emit('connection #3')


// emitter.removeAllListeners()

emitter.setMaxListeners(0) // unlimited
console.log(util.inspect(emitter.listeners('connection #1'))) // [ [Function] ]