ACLs

[hcoop/domtool2.git] / src / env.sml

diff --git a/src/env.sml b/src/env.sml
index 167adce..db92e6e 100644 (file)
--- a/src/env.sml
+++ b/src/env.sml
@@ -69,6 +69,20 @@ fun post () = !pst ()
 
 end
 
 
 end
 

+local
+    val pr = ref (fn () => ())
+in
+
+fun registerPreTycheck f =
+    let
+       val old = !pr
+    in
+       pr := (fn () => (old (); f ()))
+    end
+fun preTycheck () = !pr ()
+
+end
+

 fun badArgs (name, args) =
     (print ("Invalid arguments to " ^ name ^ "\n");
      app (fn arg => Print.preface ("Argument: ", Print.p_exp arg)) args;
 fun badArgs (name, args) =
     (print ("Invalid arguments to " ^ name ^ "\n");
      app (fn arg => Print.preface ("Argument: ", Print.p_exp arg)) args;