Sample code for understanding error handling in node.js.

caught.js

process.on('uncaughtException', function ( err ) {
    console.error('An uncaughtException was found, the program will end.');
    //hopefully do some logging.
    process.exit(1);
});

try
{
    setTimeout(function () {
        throw new Error('who will catch me?');
    }, 1);
}
catch (e) {
    console.log('not me');
}

MyClass.js

var util = require('util'),
    EventEmitter = require('events').EventEmitter;

var MyClass = function () {

	if (!(this instanceof MyClass)) return new MyClass();
	
	EventEmitter.call(this);
};

util.inherits(MyClass, EventEmitter);

oops.js

try
{
    setTimeout(function () {
        throw new Error('who will catch me?');
    }, 1);
}
catch (e) {
    console.log('not me');
}

simpleroute.js

    app.get('/', function ( req, res, next ) {

        getSomething(function ( err, data ) {
           
            if ( err ) {
                var report = new Error('unable to get something in home');
                report.status = 500;
                report.inner = err;
                next(report);
                return;
            }

            if ( !data ) {
                var report = new Error('something not found');
                report.status = 404;
                next(report);
                return;
            }

            res.send(200, data);
        })
    });

willnotthrow.js

var foo = new MyClass();

foo.on('error', function () { console.log('it blew')});

foo.emit('error');

willthrow.js

var foo = new MyClass();

foo.emit('error');