unix.lhs

http://twitter.com/janl brought me into attention about this interesting piece of code: http://www.davispj.com/2009/11/17/unix-in-python.html and this one: http://pwpwp.blogspot.com/2009/11/unix-in-14-lines-of-ruby-its-trivial.html which is implementing a barebones Unix like system in your favorite language
Here's my take on the game which is some pretty basic Haskell

You can run this code by calling runghc unix.lhs

> import System.IO
> main = 
>   putStrLn "You have no mail" >> loop
>   where 
>     loop = putStr "$ " >> hFlush stdout >> getLine >>= doCommand
>       where 
>         doCommand "uname" = putStrLn "Hunix 0.1" >> loop
>         doCommand "halt"  = return ()
>         doCommand ""      = putStrLn "$ " >> loop
>         doCommand _       = putStrLn "command not found" >> loop