app/Main.hs

@@ -1,5 +1,8 @@
 module Main (main) where
 
+import System.Random
+import Data.List
+
 ordinals :: [ String ]
 ordinals = [
     "second",
@@ -87,10 +90,18 @@ matchGifts ( i, j, k ) = filter match gifts
 giftStr :: ( String, String, String ) -> String
 giftStr (c, a, b) = c ++ " " ++ a ++ " " ++ b
 
-wrapGift :: ( Int, Int, Int, Int ) -> String
-wrapGift (i, j, k, l) = gs !! l
-    where
-        gs = map giftStr $ matchGifts (i, j, k)
+
+wrapGift :: ( Int, Int, Int ) -> [ String ]
+wrapGift (i, j, k) = map giftStr $ matchGifts (i, j, k)
+
+
+allGifts :: [ [ String ] ]
+allGifts  map wrapGift $ reverse signatures
+
+
+tuples :: [ ( String, String ) ]
+tuples = zip (reverse ordinals) allGifts
+
 
 concatLines :: [ String ] -> String
 concatLines ls = foldr (\a b -> a ++ "\n" ++ b) "" ls
@@ -105,9 +116,6 @@ makeVerse :: String -> [ String ] -> String
 makeVerse o [] = (opening o) ++ "A " ++ partridge
 makeVerse o gs = (opening o) ++ (concatLines gs) ++ "And a " ++ partridge
 
-allGifts :: [ String ]
-allGifts = map wrapGift $ reverse signatures
-
 recurseVerse :: [ ( String, String ) ] -> [ String ]
 recurseVerse [] = [ makeVerse "first" [] ]
 recurseVerse (t:ts) = [ (makeVerse ord gs) ] ++ (recurseVerse ts)
@@ -115,9 +123,18 @@ recurseVerse (t:ts) = [ (makeVerse ord gs) ] ++ (recurseVerse ts)
         ord = fst t
         gs = [(snd t)] ++ (map snd ts)
 
-tuples :: [ ( String, String ) ]
-tuples = zip (reverse ordinals) allGifts
+
+
+randomOffsets :: StdGen -> [ String ]
+randomOffsets gen gsets = map (\gs -> mod rs (length gs)) gsets
+    where rs = take (length gsets) . unfoldr (Just . random)
 
 
 main :: IO ()
-main = putStrLn $ foldr (\a b -> a ++ "\n\n" ++ b) "" $ reverse $ recurseVerse tuples
+main = do
+    gen <- newStdGen
+    let offsets = randomOffsets gen allGifts
+    print offsets
+
+
+-- putStrLn $ foldr (\a b -> a ++ "\n\n" ++ b) "" $ reverse $ recurseVerse tuples

xmasTwelve.cabal

@@ -35,6 +35,7 @@ library
   ghc-options: -Wall -Wcompat -Widentities -Wincomplete-record-updates -Wincomplete-uni-patterns -Wmissing-export-lists -Wmissing-home-modules -Wpartial-fields -Wredundant-constraints
   build-depends:
       base >=4.7 && <5
+    , random
   default-language: Haskell2010
 
 executable xmasTwelve-exe
@@ -48,6 +49,7 @@ executable xmasTwelve-exe
   ghc-options: -Wall -Wcompat -Widentities -Wincomplete-record-updates -Wincomplete-uni-patterns -Wmissing-export-lists -Wmissing-home-modules -Wpartial-fields -Wredundant-constraints -threaded -rtsopts -with-rtsopts=-N
   build-depends:
       base >=4.7 && <5
+    , random
     , xmasTwelve
   default-language: Haskell2010
 
@@ -63,5 +65,6 @@ test-suite xmasTwelve-test
   ghc-options: -Wall -Wcompat -Widentities -Wincomplete-record-updates -Wincomplete-uni-patterns -Wmissing-export-lists -Wmissing-home-modules -Wpartial-fields -Wredundant-constraints -threaded -rtsopts -with-rtsopts=-N
   build-depends:
       base >=4.7 && <5
+    , random
     , xmasTwelve
   default-language: Haskell2010