Create custom event with Node.js

node.js

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

function taskStatus(status) {
  if (status === 'done') {
     emitter.emit('done');
  } else if (status === 'doing') {
     emitter.emit('doing');
  }
}
emitter.on('done', function() {
  console.log('The task given is done!');
});
emitter.on('doing', function() {
  console.log('Doing the given task!');
});

setTimeout(taskStatus, 200, 'done');
setTimeout(taskStatus, 500, 'doing');