Install on Ubuntu:

sudo apt-get update
sudo apt-get install haskell-platform
sudo apt-get install libreadline-dev
git clone https://github.com/oneb/lil-lang
cd lil-lang
cabal update
cabal install --only-dependencies  
cabal configure
cabal build

Launch the REPL:

./dist/build/lil-lang/lil-lang

Use the REPL like this:

Ready.
Enter "exit" to exit.
> 2
2
> (+ 2 2)
4
> (define x 3)
3
> (* 2 x)
6
> (define square (lambda (x) (* x x)))
<a procedure of 1 argument(s)>
> (square 2)
4
> (square x)
9
> ((
could not parse as expression
> (define compose (lambda (f g) (lambda (x) (f (g x)))))
<a procedure of 2 argument(s)>
> ((compose square square) 3)
81
> :examples/hello-world.lil
"Hello, world"
ok
>