This is a port of the Arrowlets library to Node.js. This port was started by Chris Warburton, but Arrowlets itself was written by Khoo Yit Phang, Michael Hicks, Jeff Foster and Vibha Sazawal.

Arrowlets is a Javascript implementation of arrows, a functional programming technique for keeping function definition separate from program flow.

Arrows for functional programmers:

If you're familiar with functional programming, then you may be familiar with the concept of "monads". Arrows are a generalisation of monads, which allow for more than just sequential composition.

Arrows for everyone else:

The best way to learn about arrows is to see them being used. Let's say we have the following code:

var a = function() {
    do_something():
    b();
};
var b = function() {
    something_else();
    c();
};