[Haskell] line-based interactive program

[Christian Maeder]

Colin Runciman wrote:
> output are less than a line!  However, there is no need to build
> line-buffering into the system, because it is easily defined in Haskell:
> 
> buffer xs = foldl const xs xs

I don't find it this easy nor a good programming practise.

My interaction depends on the (subtle order of) evaluation of a pure and
total function?

Cheers Christian