Tidying up my first FizzBuzz program in Idris

philharvey+idris/fizzbuzz.idr

@@ -1,18 +1,15 @@
 module Main
 
-isFizz : Nat -> Bool
-isFizz n = modNat n 3 == 0
+mapToFizzBuzz : Nat -> String
+mapToFizzBuzz n = if isFizz n && isBuzz n then "FizzBuzz" else
+                  if isFizz n then "Fizz" else
+                  if isBuzz n then "Buzz" else show n
+          where isFizz n      = modNat n 3  == 0
+                isBuzz n      = modNat n 5  == 0
 
-isBuzz : Nat -> Bool
-isBuzz n = modNat n 5 == 0
-
-isFizzBuzz : Nat -> Bool
-isFizzBuzz n = modNat n 15 == 0
-
-fizzbuzz : String -> Nat -> String
-fizzbuzz s n = if isFizzBuzz n then s ++ "Fizz Buzz, " else
-  (if isFizz n then s ++ "Fizz, " else
-  (if isBuzz n then s ++ "Buzz, " else s ++ show n ++ ", "))
+reduceFizzBuzz : String -> Nat -> String
+reduceFizzBuzz s n = s ++ mapToFizzBuzz n ++ "\n"
 
 main : IO ()
-main = putStrLn $ foldl fizzbuzz "" [1..100]
+main = do
+  putStrLn $ foldl reduceFizzBuzz "" [1..100]