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).
1) Is there a nice (canonical) way of eliminating nested evil in Haskell?
2) If an FSM is appropriate is there a 'standard' Haskell FSM implementation?
It actually seems like a fun problem .. if I had the time ..
Andrew Wagner wrote:
This does sound interesting. Can you provide (at least some of) the code?
As I thought it would violate the group mores I didn't include the Java code here .. :-) It's at http://www.softcomp.com/pastes/ifexample.java This is a typical module .. others are worse. Heinrich Apfelmus wrote:
You probably want guards, like this
fib n | n == 0 = 0 | n == 1 = 1 | otherwise = fib (n-1) + fib (n-2)
Is this what you had in mind? module Main where foo a b c | p1 && p2 || not p3 = 42 | p1 || not p2 && p3 = 13 | otherwise = 0 where -- setup if predicates p1 = a > b p2 = a + b > 2 p3 = a - b < 1 main = do x <- return $ foo 9 2 3 print x -- 42 Thanks, Tom