gistfile1.hs

fizz n     = "fizz"
buzz n     = "buzz"
fizzbuzz n = "fizzbuzz"
as_is n    = show n

fn_table = cycle [as_is, as_is, fizz, as_is, buzz, fizz, as_is, as_is, fizz, buzz, as_is, fizz, as_is, as_is, fizzbuzz]

table = zipWith ($) fn_table [1..]

-- *Main> take 100 table
-- ["1","2","fizz","4","buzz","fizz","7","8","fizz","buzz","11","fizz","13","14","fizzbuzz","16","17","fizz","19","buzz","fizz","22","
-- 23","fizz","buzz","26","fizz","28","29","fizzbuzz","31","32","fizz","34","buzz","fizz","37","38","fizz","buzz","41","fizz","43","44","
-- fizzbuzz","46","47","fizz","49","buzz","fizz","52","53","fizz","buzz","56","fizz","58","59","fizzbuzz","61","62","fizz","64","buzz","f
-- izz","67","68","fizz","buzz","71","fizz","73","74","fizzbuzz","76","77","fizz","79","buzz","fizz","82","83","fizz","buzz","86","fizz",
-- "88","89","fizzbuzz","91","92","fizz","94","buzz","fizz","97","98","fizz","buzz"] 

-- test function --
show_at n = table !! (n - 1)
test' n = fn n == show_at n
        where fn n
                | (n `rem` 15) == 0 = "fizzbuzz"
                | (n `rem` 5)  == 0 = "buzz"
                | (n `rem` 3)  == 0 = "fizz"
                | otherwise = show n

test n = forAll (elements [1..10000]) $ \n -> test' n

-- *Main> quickCheck test
-- +++ OK, passed 100 tests.