X-Git-Url: https://git.hcoop.net/hcoop/domtool2.git/blobdiff_plain/2882ee37fded46346977da456ae793f3e6a3bfac..b3159a7069504fe2fb2b781cd6f438decaf0937a:/src/tycheck.sml?ds=sidebyside

diff --git a/src/tycheck.sml b/src/tycheck.sml
index 152eaf7..007a0fe 100644
--- a/src/tycheck.sml
+++ b/src/tycheck.sml
@@ -24,6 +24,10 @@ open Ast Print Env
 
 structure SM = StringMap
 
+val externFlag = ref false
+fun allowExterns () = externFlag := true
+fun disallowExterns () = externFlag := false
+
 local
     val unifCount = ref 0
 in
@@ -426,6 +430,23 @@ fun checkExp G (eAll as (e, loc)) =
 			(TError, loc))
 	    end
 
+	  | EALam (x, p, e) =>
+	    let
+		val p' = checkPred G p
+
+		val G' = bindVal G (x, (TAction (p, SM.empty, SM.empty), loc), NONE)
+		val t' = whnorm (checkExp G' e)
+	    in
+		case t' of
+		    (TAction _, _) => (TNested (p, t'), loc)
+		  | _ => (dte (WrongForm ("Body of nested configuration 'fn'",
+					  "action",
+					  e,
+					  t',
+					  NONE));
+			  (TError, loc))
+	    end
+
 	  | ESet (evar, e) =>
 	    let
 		val t = checkExp G e
@@ -686,8 +707,18 @@ fun checkUnit G (eAll as (_, loc)) =
 
 fun checkDecl G (d, _, loc) =
     case d of
-	DExternType name => bindType G name
-      | DExternVal (name, t) => bindVal G (name, checkTyp G t, NONE)
+	DExternType name =>
+	if !externFlag then
+	    bindType G name
+	else
+	    (ErrorMsg.error (SOME loc) "'extern type' not allowed in untrusted code";
+	     G)
+      | DExternVal (name, t) =>
+	if !externFlag then
+	    bindVal G (name, checkTyp G t, NONE)
+	else
+	    (ErrorMsg.error (SOME loc) "'extern val' not allowed in untrusted code";
+	     G)
       | DVal (name, to, e) =>
 	let
 	    val to =