--- rpl/modules/motif/XtAppMainLoop.rplc	2017/07/06 10:18:04	1.2
+++ rpl/modules/motif/XtAppMainLoop.rplc	2017/07/30 21:59:40	1.4
@@ -15,23 +15,26 @@ declareExternalFunction(XtAppMainLoop)
 			pullFromStack(appObject, external);
 			returnOnError(freeObject(appObject));
 
-			if (subType(appObject) ne APPCONTEXT) then
+			ifIsExternal(appObject, APPCONTEXT) then
+			orElse
 				executionError("Type mismatch");
 				returnOnError(freeObject(appObject));
 			endIf
 
+			intrinsic(pshcntxt);
+
 			doUntil
-				if (XtAppPending(target((sXtAppContext *)
-						objectContainer(appObject)).context) ne 0) then
-					XtAppNextEvent(target((sXtAppContext *)
-							objectContainer(appObject)).context, &event);
+				if (XtAppPending(target(objectContainer(sXtAppContext,
+						appObject)).context) ne 0) then
+					XtAppNextEvent(target(objectContainer(sXtAppContext,
+							appObject)).context, &event);
 
 					if (event.type eq DestroyNotify) then
 						if (event.xdestroywindow.window eq
-								XtWindow(target((sXtAppContext *)
-								objectContainer(appObject)).widget)) then
-							XtAppSetExitFlag(target((sXtAppContext *)
-									objectContainer(appObject)).context);
+								XtWindow(target(objectContainer(sXtAppContext,
+								appObject)).widget)) then
+							XtAppSetExitFlag(target(objectContainer(
+									sXtAppContext, appObject)).context);
 						endIf
 					endIf
 
@@ -40,13 +43,15 @@ declareExternalFunction(XtAppMainLoop)
 					pollSignalsAndInterrupts();
 					usleep(10000);
 				endIf
-			repeatUntil(XtAppGetExitFlag(target((sXtAppContext *)
-					objectContainer(appObject)).context) or
+			repeatUntil(XtAppGetExitFlag(target(
+					objectContainer(sXtAppContext, appObject)).context) or
 					(stopRequest eq -1) or
 					(exitMainLoop ne 0))
 
-			XtDestroyApplicationContext(target((sXtAppContext *)
-					objectContainer(appObject)).context);
+			intrinsic(pulcntxt);
+
+			XtDestroyApplicationContext(target(
+					objectContainer(sXtAppContext, appObject)).context);
 		orElse
 			executionError("Application not initialized");
 			returnOnError();