quicksort works

sample-programs/Quicksort.crf

@@ -1,3 +1,21 @@
+toStr : List Int -> List Char
+toStr xs = case xs of
+    Cons a as => Cons (toChar a) (toStr as)
+    Nil => Nil
+
+toChar : Int -> Char
+toChar x = case x of
+    0 => '0'
+    1 => '1'
+    2 => '2'
+    3 => '3'
+    4 => '4'
+    5 => '5'
+    6 => '6'
+    7 => '7'
+    8 => '8'
+    9 => '9'
+
 filter p xs = case xs of
     Nil => Nil
     Cons x xs => case p x of
@@ -8,16 +26,29 @@ filter p xs = case xs of
     Nil => bs
     Cons x xs => Cons x (xs ++ bs)
 
-.<= a b = case a < b of
-    False => a == b
-    True => True
+.:: a as = Cons a as
 
+quicksort : List Int -> List Int
 quicksort xs = case xs of
     Nil => Nil
-    Cons a as => quicksort (filter (\y. a < y) xs) ++ (Cons a (quicksort (filter (\y. y <= a)) xs))
+    Cons a as => let smaller = quicksort (filter (\y. y < a) xs)
+                  in let bigger = quicksort (filter (\y. a < y) xs)
+                      in smaller ++ (a :: bigger)
 
-head xs = case xs of
-    Cons a _ => a
+descList : Int -> Int -> List Int
+descList from to = case to < from of
+   False => Cons to (descList from (to - 1)) 
+   True => Nil
 
-main : Int
-main = head (quicksort (Cons 9 (Cons 8 (Cons 7 (Cons 6 (Cons 5 (Cons 4 (Cons 3 (Cons 2 (Cons 1 (Cons 0 Nil)))))))))))
+main = let list = (5 :: (2 :: (8 :: (9 :: (6 :: (0 :: (1 :: Nil)))))))
+        in printStr (toStr (quicksort list))
+
+{-
+
+-- Program output --
+0125689
+In dispose
+Out dispose
+ExitSuccess
+
+-}