Index: library/nx/nx.tcl
===================================================================
diff -u -r5fa3584b0f682d4103c39af82357713871f1de0c -r96716c484bb18d390fef1eecdca764b56121dc4d
--- library/nx/nx.tcl	(.../nx.tcl)	(revision 5fa3584b0f682d4103c39af82357713871f1de0c)
+++ library/nx/nx.tcl	(.../nx.tcl)	(revision 96716c484bb18d390fef1eecdca764b56121dc4d)
@@ -614,7 +614,9 @@
         }
       }
     }
+
     if {[info exists type]} {
+      if {$type eq "switch"} {error "switch is not allowed as type for object parameter $name"}
       lappend opts -type $type
     }
 
@@ -801,6 +803,7 @@
     set objopts [list]
     set methodopts [list]
     set type ""
+
     if {[info exists :required] && ${:required}} {
       lappend objopts required
       lappend methodopts required