Index: openacs-4/packages/categories/www/cadmin/tree-order-update.tcl
===================================================================
RCS file: /usr/local/cvsroot/openacs-4/packages/categories/www/cadmin/tree-order-update.tcl,v
diff -u -N -r1.11 -r1.12
--- openacs-4/packages/categories/www/cadmin/tree-order-update.tcl	8 May 2018 16:21:26 -0000	1.11
+++ openacs-4/packages/categories/www/cadmin/tree-order-update.tcl	9 May 2018 15:33:30 -0000	1.12
@@ -34,8 +34,8 @@
     set last_ind [expr {($count / 5) + 1}]
 
     set count 1
-    set stack {}
-    set done_list {}
+    set stack [list]
+    set done_list [list]
     # put toplevel categories on stack
     if {[info exists child(-1)]} {
         set stack [lsort -integer -index 0 $child(-1)]