diff -r 291cc01f56f5 -r bea354f6ff21 src/Pure/Isar/proof.ML
--- a/src/Pure/Isar/proof.ML Thu Mar 17 16:56:44 2016 +0100
+++ b/src/Pure/Isar/proof.ML Fri Mar 18 16:26:35 2016 +0100
@@ -173,6 +173,10 @@
(context * thm list list -> state -> state) *
(context * thm list list -> context -> context)};
+val _ =
+ PolyML.addPrettyPrinter (fn _ => fn _ => fn _: state =>
+ Pretty.to_polyml (Pretty.str ""));
+
fun make_goal (statement, using, goal, before_qed, after_qed) =
Goal {statement = statement, using = using, goal = goal,
before_qed = before_qed, after_qed = after_qed};