To see it in action....
First, compile Main.hs using ghcjs:
next, run a server in Main.jsexe :
cd Main.jsexe python -m SimpleHTTPServer
finally, view the results in your brower.
If you just want to see the results, follow the link below: https://dc25.github.io/ghcjsCallback
If you want to see a slightly modified version that runs under node.js, look at the nodejs branch.