diff -r aeca05e62fef -r 5e25cc741ab9 src/Pure/context_position.ML
--- a/src/Pure/context_position.ML	Sat Feb 22 18:07:31 2014 +0100
+++ b/src/Pure/context_position.ML	Sat Feb 22 20:52:43 2014 +0100
@@ -6,6 +6,7 @@
 
 signature CONTEXT_POSITION =
 sig
+  val is_visible_generic: Context.generic -> bool
   val is_visible: Proof.context -> bool
   val is_visible_global: theory -> bool
   val if_visible: Proof.context -> ('a -> unit) -> 'a -> unit