--- stack/stack.c	2002/03/27 14:45:17	1.121
+++ stack/stack.c	2002/03/27 14:49:56	1.122
@@ -1109,7 +1109,7 @@
   }
 
   if(myenv.interactive) {
-    printf("Stack version $Revision: 1.121 $\n\
+    printf("Stack version $Revision: 1.122 $\n\
 Copyright (C) 2002  Mats Alritzson and Teddy Hogeborn\n\
 Stack comes with ABSOLUTELY NO WARRANTY; for details type 'warranty;'.\n\
 This is free software, and you are welcome to redistribute it\n\
@@ -1651,7 +1651,7 @@
 
   iterator= foo;
 
-  while(iterator!=NULL) {
+  while(iterator->type!=empty) {
     push_val(env, CAR(iterator));
     push_val(env, loop);
     eval(env); if(env->err) return;