NodeJS - How can I use a function to set a listeners callback?

Question

NodeJS - How can I use a function to set a listeners callback?

var events = require('events');
var requests = new events.EventEmitter();
function setListenerCallback(callback) {
    requests.on('randomEvent', callback(message));
}
setListenerCallback(function (e) {
    console.log(e);
});
Result: callback is undefined.

As you can see I am trying to set the listeners callback function from a functions argument. The result is that the function is type 'undefined' and therefore outside of the listeners scope.

So how can I use a function to set a listeners callback?
How can I access the parent functions scope from the listener?

javascript
node.js
events

Answer 1

There was a bug in the code:

Old code:

var events = require('events');
var requests = new events.EventEmitter();
function setListenerCallback(callback) {
    requests.on('randomEvent', callback(message));
}
setListenerCallback(function (e) {
    console.log(e);
});

New code:

var events = require('events');
var requests = new events.EventEmitter();
function setListenerCallback(callback) {
    requests.on('randomEvent', callback);
}
setListenerCallback(function (e) {
    console.log(e);
});

Now when the event is fired callback is called.