fizzbuzz.hs

fizzbuzz.hs

import Data.Maybe
import Data.Monoid
import Control.Applicative

-- Mostly stolen from an answer found posted on reddit.
-- This formulation achieves a high level of modularity and clarity.
-- It is modular with respect to adding more numbers to fizz and buzz against,
-- and captures the idea of `show`ing the number by default elegantly.
t m s n = if mod n m == 0 then Just s else Nothing
-- instance Applicative ((->) a) where (<*>) f g x = f x (g x)
fz = fromMaybe . show <*> (t 3 "fizz" <> t 5 "buzz" <> t 7 "hiss" <> t 11 "howl")        
main = mapM_ (putStrLn . fz) [1..100]

-- fz = fromMaybe . show <*> (\t -> t 3 "fizz" <> t 5 "buzz" <> t 7 "hiss" <> t 11 "howl") (\m s n -> s <$ guard (mod n m == 0))
-- fz n = (\t -> show n `t` (["fizz" | mod n 3 == 0] ++ ["buzz" | mod n 5 == 0])) (\d x -> case x of [] -> d; _ -> concat x)

fromList xs = fromMaybe . show <*> (mconcat $ map (uncurry t) xs)
fromList [(3, "Fizz"), (5, "Buzz"), (7, "Hiss")] (3*5*7) -- => "FizzBuzzHiss"