proper Path.print;

--- a/src/Pure/General/path.ML	Wed Jun 29 23:43:48 2011 +0200
+++ b/src/Pure/General/path.ML	Thu Jun 30 00:01:00 2011 +0200
@@ -163,7 +163,7 @@
 (* base element *)
 
 fun split_path f (Path (Basic s :: xs)) = f (Path xs, s)
-  | split_path _ path = error ("Cannot split path into dir/base: " ^ quote (implode_path path));
+  | split_path _ path = error ("Cannot split path into dir/base: " ^ print path);
 
 val dir = split_path #1;
 val base = split_path (fn (_, s) => Path [Basic s]);