1 files changed, 4 insertions, 0 deletions
diff --git a/common.sml b/common.sml
index e947e0f..e648203 100644
--- a/common.sml
+++ b/common.sml
@@ -175,6 +175,10 @@ val R = fn z => bind A1 (fn ((output, _), n) => app (fn f => f ())
 type ('t, 'a, 'b, 'c) a1printer = (bool * ((string -> unit) * 'a)) * 'b
         -> 't -> ((bool * ((string -> unit) * 'a)) * 'b -> 'c) -> 'c
 
+type ('t1, 't2, 'a, 'b, 'c) a2printer =
+    (bool * ((string -> unit) * 'a)) * 'b -> 't1 -> 't2 ->
+        ((bool * ((string -> unit) * 'a)) * 'b -> 'c) -> 'c
+
 fun die code g =
 let
   fun finish (true, _) = raise Unreachable