Index: openacs-4/packages/acs-tcl/tcl/util-diff-procs.tcl
===================================================================
RCS file: /usr/local/cvsroot/openacs-4/packages/acs-tcl/tcl/util-diff-procs.tcl,v
diff -u -r1.6 -r1.7
--- openacs-4/packages/acs-tcl/tcl/util-diff-procs.tcl	25 Apr 2018 19:23:26 -0000	1.6
+++ openacs-4/packages/acs-tcl/tcl/util-diff-procs.tcl	9 May 2018 15:33:29 -0000	1.7
@@ -115,7 +115,7 @@
     package require struct::list
 
     set frag $old
-    set old_list {}
+    set old_list [list]
     while {$frag ne ""} {
 	if {![regexp "(\[^<]*)(<(/?)(\[^ \r\n\t>]+)(\[^>]*)>)?(.*)" $frag match pretag fulltag close tag tagbody frag]} {
 	    # we should never get here, the regexp should match anything
@@ -126,7 +126,7 @@
 	}
 	if {$pretag ne ""} {
 	    set pretag [string map {\n " "} $pretag]
-	    set pretag2 {}
+	    set pretag2 [list]
 	    foreach element [split $pretag " "] {
 		if {[string trim $element] ne ""} {
 		    lappend pretag2 [string trim $element]
@@ -142,7 +142,7 @@
     }
 
     set frag $new
-    set new_list {}
+    set new_list [list]
     while {$frag ne ""} {
 	if {![regexp "(\[^<]*)(<(/?)(\[^ \r\n\t>]+)(\[^>]*)>)?(.*)" $frag match pretag fulltag close tag tagbody frag]} {
 	    # we should never get here, the regexp should match anything
@@ -152,7 +152,7 @@
 	}
 	if {$pretag ne ""} {
 	    set pretag [string map {\n " "} $pretag]
-	    set pretag2 {}
+	    set pretag2 [list]
 	    foreach element [split $pretag " "] {
 		if {[string trim $element] ne ""} {
 		    lappend pretag2 [string trim $element]