Functional I/O Night

Functional programming encourages writing pure functions (http://en.wikipedia.org/wiki/Pure_function) that have no side effects. But if you can't have side effects (like writing to a file or displaying graphics on a monitor), how do you get a computer to actually do anything useful?

This time we'll be returning to our hack-along/jam format. We'll try to explain to ourselves how different functional programming languages look at purity by trying it out on the night with a laptop and projector.

We'll start at 19:30, but someone should be around at the Skiff to let you in from 19:00.