diff -r 6a72af4e84b8 -r b4534348b8fd src/Pure/codegen.ML
--- a/src/Pure/codegen.ML	Thu Oct 29 16:59:12 2009 +0100
+++ b/src/Pure/codegen.ML	Thu Oct 29 17:58:26 2009 +0100
@@ -137,7 +137,7 @@
   | args_of (Ignore :: ms) (_ :: xs) = args_of ms xs
   | args_of (_ :: ms) xs = args_of ms xs;
 
-fun num_args_of x = length (List.filter is_arg x);
+fun num_args_of x = length (filter is_arg x);
 
 
 (**** theory data ****)