I'm working on a project (in Haskell) and was given some old Java code to indicate the required functionality for a particular function. It's a page of nested (4 deep) if statements. (That's probably why they gave me the code, no one could describe it). I would normally convert this to an FSM, ..... but this is Haskell! So, 1) Is there a nice (canonical) way of eliminating nested evil in Haskell? I thought that perhaps making a tuple of all the if's conditions and patterm matching on them might make a bit more comprehensible. Likely there's a better way. 2) If an FSM is appropriate is there a 'standard' Haskell FSM implementation? I looked around and could find very little. One paper talked about Arrows but that seems like a bit of overkill .. It actually seems like a fun problem .. if I had the time .. Any thoughts greatly appreciated! Tom