Tail recursive length on cons list

gibbon-compiler/examples/tail_recursion/ConsListLength.hs

@@ -0,0 +1,27 @@
+module ConsListLength where 
+
+
+data ConsIntList = Cons Int (ConsIntList) | Nil
+
+
+
+mkConsIntList :: Int -> ConsIntList
+mkConsIntList len = if len <= 0 
+                    then Nil 
+                    else let 
+                           rst = mkConsIntList (len-1)
+                          in Cons len rst
+
+
+length :: ConsIntList -> Int -> Int
+length lst accum = case lst of 
+                    Nil -> accum 
+                    Cons x rst -> length rst (accum+1)
+
+
+
+gibbon_main = 
+    let n = sizeParam
+        lst = mkConsIntList n
+        len = iterate (length lst 0)
+      in len