Index: library/nx/nx.tcl
===================================================================
diff -u -N -r7e754788ca3af3d878c38ddb924f227645306bc0 -r03bde7ee87099accfec6d374b78df464d596d768
--- library/nx/nx.tcl	(.../nx.tcl)	(revision 7e754788ca3af3d878c38ddb924f227645306bc0)
+++ library/nx/nx.tcl	(.../nx.tcl)	(revision 03bde7ee87099accfec6d374b78df464d596d768)
@@ -2395,7 +2395,7 @@
                pname parameterOptions _ _
 
     set paramOptsList [split $parameterOptions ,]
-    if {[info exists defaultValue] && "substdefault" in [split $paramOptsList ,]} {
+    if {[info exists defaultValue] && "substdefault" in $paramOptsList} {
       if {[string match {*\[*\]*} $defaultValue]} {
         if {![info complete $defaultValue]} {
           return -code error "substdefault: default '$defaultValue' is not a complete script"