The example code doesn't work.

[viclib]

Press ENTER or type command to continue
[1 of 1] Compiling Main ( socketio.hs, socketio.o )

socketio.hs:13:24: Not in scope: ‘liftIO’

socketio.hs:13:31: Not in scope: ‘launchMissile’

shell returned 1

Press ENTER or type command to continue
/bin/bash: ./socketio: No such file or directory

[davnils]

liftIO can be found in Control.Monad.Trans. The launchMissiles function is just some arbitrary IO-action.
The example is probably only meant to provide a basic idea of how to use the package, unless you have access to a missile facility.

[banacorn]

Yes, thank you @davnils.

And @viclib, even if you have liftIO and a missile facility ready, I'm afraid the code still won't work under the present socket.io 1.0. I apologize for that, I'm working on it :)